piperidines and Colorectal-Neoplasms

The Agency for Healthcare Research and Quality, in partnership with the American College of Surgeons and the Johns Hopkins Medicine Armstrong Institute for Patient Safety and Quality, has developed the Safety Program for Improving Surgical Care and Recovery (ISCR), which is a national effort to disseminate best practices in perioperative care to more than 750 hospitals across multiple procedures in the next 5 years. The program will integrate evidence-based processes central to enhanced recovery and prevention of surgical site infection, venous thromboembolic events, catheter-associated urinary tract infections with socioadaptive interventions to improve surgical outcomes, patient experience, and perioperative safety culture. The objectives of this review are to evaluate the evidence supporting anesthesiology components of colorectal (CR) pathways and to develop an evidence-based CR protocol for implementation. Anesthesiology protocol components were identified through review of existing CR enhanced recovery pathways from several professional associations/societies and expert feedback. These guidelines/recommendations were supplemented by evidence made further literature searches. Anesthesiology protocol components were identified spanning the immediate preoperative, intraoperative, and postoperative phases of care. Components included carbohydrate loading, reduced fasting, multimodal preanesthesia medication, antibiotic prophylaxis, blood transfusion, intraoperative fluid management/goal-directed fluid therapy, normothermia, a standardized intraoperative anesthesia pathway, and standard postoperative multimodal analgesic regimens.

Topics: Anesthesia; Anesthesiology; Anti-Bacterial Agents; Antibiotic Prophylaxis; Carbohydrates; Colorectal Neoplasms; Colorectal Surgery; Evidence-Based Medicine; Fluid Therapy; Humans; Patient Safety; Perioperative Care; Piperidines; Quality of Health Care; Randomized Controlled Trials as Topic; Safety Management; Surgical Procedures, Operative; Thromboembolism; Treatment Outcome; United States; United States Agency for Healthcare Research and Quality; Urinary Tract Infections

Angiogenesis is essential for tumor growth and metastasis. The main regulators of the process are the signaling cascades of VEGF-, PDGF- and FGF receptors. Inhibition of these pathways holds potential therapeutic benefit not only for cancer patients, but also for the treatment of other diseases. This paper summarizes the experimental and clinical results of studies available so far on the multi-target tyrosine kinase inhibitor nintedanib (BIBF 1120). According to these studies, nintedanib effectively inhibits VEGFR-, PDGFR- and FGFR signalization and thus the proliferation and survival of cell types which highly express these receptors (i.e. endothelial and smooth muscle cells and pericytes). In vitro studies and in vivo xenograft experiments have provided promising results. In the clinical setting, BIBF 1120 seems to be effective and well tolerated in various tumor types, such as lung, prostate, colorectal and hepatocellular carcinoma, as well as in gynecological tumors. The main adverse events are gastrointestinal toxicities and the reversible elevation of liver enzyme levels. Nintedanib might also be combined with paclitaxel, carboplatin, pemetrexed and docetaxel. There are several ongoing clinical trials testing the efficacy of BIBF 1120.

Topics: Animals; Antineoplastic Agents; Axitinib; Benzenesulfonates; Carcinoma, Hepatocellular; Clinical Trials as Topic; Colorectal Neoplasms; Digestive System; Enzyme Inhibitors; Female; Genital Neoplasms, Female; Humans; Imidazoles; Indazoles; Indoles; Liver Neoplasms; Lung Neoplasms; Male; Neoplasms; Niacinamide; Oligonucleotides; Phenylurea Compounds; Phthalazines; Piperidines; Prostatic Neoplasms; Protein-Tyrosine Kinases; Pyridines; Pyrimidines; Quinazolines; Receptors, Fibroblast Growth Factor; Receptors, Platelet-Derived Growth Factor; Receptors, Vascular Endothelial Growth Factor; Signal Transduction; Sorafenib; Sulfonamides; Xenograft Model Antitumor Assays

Farnesyl transferase inhibitors (FTIs) are anticancer agents that were designed to block the post-translational attachment of the prenyl moiety to C-terminal cysteine residue of Ras and thus inactivate it. Because Ras plays an important role in tumour progression and the ras mutation is one of the most frequent aberrations in cancer, FTIs have been expected to exert excellent therapeutic activities. Phase I and II clinical trials confirmed relevant antitumour activity and low toxicity; however, no improvement in overall survival has been reported in Phase III trials. The exact mechanism of action of this class of agents is currently unknown. Increasing lines of evidence indicate that the cytotoxic actions of FTIs are not due to the inhibition of Ras proteins exclusively, but to the modulation of other targets, including RhoB, the centromere-binding proteins and other proteins that have not yet been identified. This review describes the pharmacological and clinical data as well as mechanisms of action of FTIs, especially lonafarnib (SCH-66336), a non-peptidomimetic inhibitor that has shown anticancer activity.

Topics: Animals; Antineoplastic Agents; Carcinoma, Non-Small-Cell Lung; Colorectal Neoplasms; Drug Administration Schedule; Drug Evaluation, Preclinical; Drug Therapy, Combination; Enzyme Inhibitors; Farnesyltranstransferase; Humans; Leukemia; Lung Neoplasms; Piperidines; Pyridines; Randomized Controlled Trials as Topic

A number of therapeutic agents have been developed which have anti-angiogenic potential. Here we present the most recent data from clinical trials with some of the promising inhibitors of angiogenesis.. Agents that target the vascular endothelial growth factor signaling pathway are the furthest along in clinical development. The last year has brought US Food and Drug Administration approval of bevacizumab (Avastin), a recombinant humanized anti-vascular endothelial growth factor monoclonal antibody. Bevacizumab has demonstrated a survival advantage in combination with chemotherapy for patients with metastatic colorectal cancer. Other agents with early promising results include PTK787/ZK 222584 (Vatalanib), ZD6474, and BAY 43-9006 (Sorafenib).. Angiogenesis inhibitors show promise, but evaluation for optimal efficacy has been a problem, given that the mechanisms of action of these agents differ from conventional cytotoxic agents and surrogate markers for inhibition of angiogenesis are not available.

Topics: Angiogenesis Inhibitors; Animals; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Benzenesulfonates; Bevacizumab; Colorectal Neoplasms; Humans; Neoplasms; Neovascularization, Pathologic; Niacinamide; Phenylurea Compounds; Phthalazines; Piperidines; Pyridines; Quinazolines; Randomized Controlled Trials as Topic; Signal Transduction; Sorafenib; Vascular Endothelial Growth Factor A

Phase I/II studies suggest that the combination of irinotecan with capecitabine is feasible and has promising activity. Diarrhea and neutropenia are dose limiting. Overall response rates (RRs) in the 40% to 60% range are seen from preliminary data. Work in progress is assessing the combination of irinotecan with UFT/leucovorin (LV). The use of irinotecan together with raltitrexed is also being investigated, as is its combination with oxaliplatin. Two phase II studies of irinotecan plus oxaliplatin in second-line patients report median survivals of 11-12 months. It seems possible to safely escalate the dose of single-agent irinotecan to 500 mg/m(2) in patients showing good tolerance of the drug. Irinotecan can be used in combination with LV5FU2 at doses up to 260 mg/m(2), especially if only one bolus of 5-fluorouracil (5-FU) is given. Control of tumor growth is achieved in 90% of patients. Preliminary data suggest that regimens based on 5-FU/LV and irinotecan can safely be combined with the anti-epidermal growth factor receptor (EGFR) antibody cetuximab. In patients with EGFR-positive tumors, this may prove an effective means of increasing response rate or combating treatment resistance. Following evidence that COX-2 inhibition can slow progression in familial adenomatous polyposis, celecoxib is to be studied in metastatic colorectal cancer (CRC). In vitro, the cyclin-dependent kinase inhibitor flavopiridol enhances the induction of apoptosis by chemotherapy. Clinically, it can safely be administered with irinotecan, and studies in CRC are planned.

Topics: Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antineoplastic Agents, Phytogenic; Antineoplastic Combined Chemotherapy Protocols; Camptothecin; Capecitabine; Cetuximab; Clinical Trials as Topic; Colorectal Neoplasms; Cyclooxygenase 2; Deoxycytidine; Drug Administration Schedule; Enzyme Inhibitors; Flavonoids; Fluorouracil; Humans; Immunologic Factors; Irinotecan; Isoenzymes; Leucovorin; Membrane Proteins; Organoplatinum Compounds; Oxaliplatin; Piperidines; Prostaglandin-Endoperoxide Synthases; Quinazolines; Thiophenes; Treatment Outcome

The inhibitors of VEGF-mediated signaling continue to wind their way through extensive preclinical and clinical development paths. Whereas the first phase III trial did not meet its endpoints, one hopes that the others will. As we learn more about the VEGF pathways in the laboratory and the clinic, we can interpret with greater certainty what role these drugs or their successors will have in the treatment of human cancers.

Topics: Angiogenesis Inhibitors; Animals; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antineoplastic Agents; Bevacizumab; Clinical Trials as Topic; Colorectal Neoplasms; Drug Design; Drug Screening Assays, Antitumor; Endothelial Growth Factors; Enzyme Inhibitors; Humans; Indoles; Intercellular Signaling Peptides and Proteins; Lymphokines; Neoplasm Proteins; Neoplasms; Neovascularization, Pathologic; Phthalazines; Piperidines; Pyridines; Pyrroles; Quinazolines; Recombinant Proteins; RNA, Catalytic; Treatment Failure; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factor Receptor-1; Vascular Endothelial Growth Factor Receptor-2; Vascular Endothelial Growth Factors

MMR proficient (pMMR) colorectal cancer (CRC) is usually unresponsive to immunotherapy. Recent data suggest that ibrutinib may enhance the anti-tumour activity of anti-PD-1 immunotherapy. In this study, we evaluated the safety and efficacy of ibrutinib plus pembrolizumab in refractory metastatic CRC.. This was a phase 1/2 study in patients with refractory metastatic pMMR CRC. The primary endpoints for phases 1 and 2 were maximum tolerated dose (MTD) and disease control rate, respectively. The secondary endpoints were safety, progression-free survival (PFS) and overall survival (OS).. A total of 40 patients were enrolled. No dose-limiting toxicity was observed, and MTD was not identified. The highest tested dose of ibrutinib, 560 mg once daily, was combined with a fixed dose of pembrolizumab 200 mg every 3 weeks for the phase 2 portion. The most common grade 3/4 treatment-related adverse events were anaemia (21%), fatigue (8%) and elevated alkaline phosphatase (8%). Among 31 evaluable patients, 8 (26%) achieved stable disease, and no objective response was observed. The median PFS and OS were 1.4 and 6.6 months, respectively.. Ibrutinib 560 mg daily plus pembrolizumab 200 mg every 3 weeks appears to be well tolerated with limited anti-cancer activity in metastatic CRC. CLINICALTRIALS.. NCT03332498.

Topics: Adenine; Adenocarcinoma; Adult; Aged; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Colorectal Neoplasms; DNA Mismatch Repair; Female; Humans; Male; Maximum Tolerated Dose; Middle Aged; Neoplasm Metastasis; Piperidines; Progression-Free Survival; Treatment Outcome; Young Adult

Microsatellite-stable metastatic colorectal cancer is typically unresponsive to immunotherapy. This phase 3 study was designed to assess atezolizumab plus cobimetinib in metastatic colorectal cancer. Here, we report the comparison of atezolizumab plus cobimetinib or atezolizumab monotherapy versus regorafenib in the third-line setting.. IMblaze 370 is a multicentre, open-label, phase 3, randomised, controlled trial, done at 73 academic medical centres and community oncology practices in 11 countries. Patients aged at least 18 years with unresectable locally advanced or metastatic colorectal cancer, baseline Eastern Cooperative Oncology Group performance status of 0-1, and disease progression on or intolerance to at least two previous systemic chemotherapy regimens were enrolled. We used permuted-block randomisation (block size four) to assign patients (2:1:1) via an interactive voice and web response system to atezolizumab (840 mg intravenously every 2 weeks) plus cobimetinib (60 mg orally once daily for days 1-21 of a 28-day cycle), atezolizumab monotherapy (1200 mg intravenously every 3 weeks), or regorafenib (160 mg orally once daily for days 1-21 of a 28-day cycle). Stratification factors were extended RAS status (wild-type vs mutant) and time since diagnosis of first metastasis (<18 months vs ≥18 months). Recruitment of patients with high microsatellite instability was capped at 5%. The primary endpoint was overall survival in the intention-to-treat population. Safety was assessed in the population of patients who received at least one dose of their assigned treatment. IMblaze370 is ongoing and is registered with ClinicalTrials.gov, number NCT02788279.. Between July 27, 2016, and Jan 19, 2017, 363 patients were enrolled (183 patients in the atezolizumab plus cobimetinib group, 90 in the atezolizumab group, and 90 in the regorafenib group). At data cutoff (March 9, 2018), median follow-up was 7·3 months (IQR 3·7-13·6). Median overall survival was 8·87 months (95% CI 7·00-10·61) with atezolizumab plus cobimetinib, 7·10 months (6·05-10·05) with atezolizumab, and 8·51 months (6·41-10·71) with regorafenib; the hazard ratio was 1·00 (95% CI 0·73-1·38; p=0·99) for the combination versus regorafenib and 1·19 (0·83-1·71; p=0·34) for atezolizumab versus regorafenib. Grade 3-4 adverse events were reported in 109 (61%) of 179 patients in the atezolizumab plus cobimetinib group, 28 (31%) of 90 in the atezolizumab group, and 46 (58%) of 80 in the regorafenib group. The most common all-cause grade 3-4 adverse events in the combination group were diarrhoea (20 [11%] of 179), anaemia (ten [6%]), increased blood creatine phosphokinase (12 [7%]), and fatigue (eight [4%]). Serious adverse events were reported in 71 (40%) of 179 patients in the combination group, 15 (17%) of 90 in the atezolizumab group, and 18 (23%) of 80 in the regorafenib group. Two treatment-related deaths occurred in the combination group (sepsis) and one in the regorafenib group (intestinal perforation).. IMblaze370 did not meet its primary endpoint of improved overall survival with atezolizumab plus cobimetinib or atezolizumab versus regorafenib. The safety of atezolizumab plus cobimetinib was consistent with those of the individual drugs. These results underscore the challenge of expanding the benefit of immunotherapy to patients whose tumours have lower baseline levels of immune inflammation, such as those with microsatellite-stable metastatic colorectal cancer.. F Hoffmann-La Roche Ltd/Genentech Inc.

Topics: Aged; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Azetidines; Colorectal Neoplasms; Female; Follow-Up Studies; Humans; Liver Neoplasms; Male; Middle Aged; Phenylurea Compounds; Piperidines; Prognosis; Pyridines; Salvage Therapy; Survival Rate

To investigate the effects of different anesthesia depth on stress response in elderly patients undergoing elective laparoscopic surgery for colorectal cancer.. A total of 105 ASA I-III patients aged 60-91 years undergoing elective laparoscopic surgery for colorectal cancer with general anesthesia were randomized into 3 groups, namely group A with a target Narcotrend index (NI) maintained at D0 level, group B with a NI at D2 level, and group C with a NI at E1 level. The anesthetics (profopol and remifentanil) were adjusted according to Narcotrend monitoring results to maintain the specified anesthesia depth. The patients' heart rate (HR) and mean artery pressure (MAP) were recorded before anesthesia (T0), before intubation (T1), immediately after intubation (T2), at 2 min before pneumoperitoneum (T3), 2 min after pneumoperitoneum (T4), at the end of the surgery (T5) and extubation (T6). Serum levels of cortisol, adrenocorticotropic hormone (ACTH), endothelin-1 (ET-1), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) and C-reactive protein (CRP) were measured by standard ELISA and radioimmunoassay before anesthesia (Ta), at the end of the surgery (Tb) and 1 day after the surgery (Tc).. HR and MAP in group A increased significantly at T2, T4, and T6 compared to those at T0 (P<0.05), and were higher than those in group B and group C (P<0.05). The MAP in all the 3 groups all decreased at T1 and T3 (P<0.05 or P<0.01), and was markedly lower in group C than in groups A and B (P<0.05). The incidence of hypertension was significantly higher in group A than in groups B and C (P<0.05), while the incidence of hypotension was much higher in group C (P<0.01). There were no obvious differences in serum levels of cortisol, ACTH, CRP, IL-6, TNF-a, or ET-1 among the groups at Ta (P>0.05). The serum levels of ACTH in the 3 groups all significantly increased at Tb and Tc (P<0.01). CRP, IL-6 and TNF-a levels in group A were increased at Tb and Tc (P<0.05 or P<0.01) and significantly higher than those in groups B and C (P<0.05 or P<0.01). Cortisol in groups A and B increased at Tb and Tc (P<0.05) to a significantly higher level than that in group C (P<0.01). ET-1 level in group C at Tb and Tc was lower than those in groups A and B (P<0.05 or P<0.01).. Maintaining the anesthesia depth for a NI at the D2 and E1 level can both attenuate the stress response in elderly patients undergoing laparoscopic surgery for colorectal cancer, but the hemodynamic stability can be better at a D2 level.

Topics: Adrenocorticotropic Hormone; Aged; Aged, 80 and over; Anesthesia, General; Blood Pressure; C-Reactive Protein; Colorectal Neoplasms; Elective Surgical Procedures; Endothelin-1; Heart Rate; Humans; Hydrocortisone; Interleukin-6; Laparoscopy; Middle Aged; Piperidines; Propofol; Remifentanil; Tumor Necrosis Factor-alpha

Vandetanib is a tyrosine kinase inhibitor of both the vascular endothelial growth factor (VEGFR) and epidermal growth factor (EGFR) receptors. The primary objectives of this study were to determine the maximum tolerated dose of vandetanib with capecitabine and oxaliplatin, without and with bevacizumab, for the first line treatment of metastatic colorectal cancer (mCRC), and to define the dose limiting toxicities.. Three cohorts of patients were studied, with capecitabine at 1,000 mg/m(2) twice daily p.o. on days 1-14 of a 3 week cycle, with oxaliplatin i.v. at 130 mg/m(2) on day 1. Vandetanib dosing was 100 mg/day in cohort 1 and 300 mg/day in cohorts 2 and 3. Bevacizumab was added in cohort 3 at 7.5 mg/kg i.v. on day 1 every 3 weeks.. Thirteen patients were enrolled and received from one to eight cycles per patient. Grade 4 dermatitis developed in one patient in the first cohort, and the cohort was expanded to six patients with no further dose limiting toxicities (DLT). The second cohort of 3 patients was well tolerated. The third cohort resulted in grade 3 diarrhea, requiring several days of hospitalization and i.v. hydration, in 3 of the 4 patients. Given the severity and duration of diarrhea, each of these was considered a DLT, and therefore cohort 3 was considered to be above the maximum tolerated dose. Six of the 13 patients achieved a partial or complete remission (46%). The time to progression ranged from 2 to 14 months.. Vandetanib at doses of 100 mg and 300 mg daily in combination with capecitabine and oxaliplatin was well tolerated. However, the addition of bevacizumab resulted in severe diarrhea in three out of four patients. Bevacizumab was not well tolerated with vandetanib and XELOX in combination.

Topics: Adult; Aged; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Bevacizumab; Capecitabine; Colorectal Neoplasms; Deoxycytidine; Diarrhea; Female; Fluorouracil; Humans; Male; Middle Aged; Neoplasm Metastasis; Oxaloacetates; Piperidines; Protein Kinase Inhibitors; Quinazolines; Vascular Endothelial Growth Factor Receptor-2

The primary objective was to determine if a single dose of casopitant 90 mg added to ondansetron and dexamethasone would improve the control of chemotherapy-induced nausea and vomiting (CINV) over 0-120 h following initiation of oxaliplatin-based moderately emetic chemotherapy (MEC) compared to ondansetron and dexamethasone alone.. Patients with colorectal cancer received either casopitant or placebo intravenously (IV) added to ondansetron 8 mg bid oral on study days 1 to 3 and one dose of dexamethasone 8 mg IV given prior to starting the oxaliplatin on day 1. The primary endpoint was the percentage of subjects achieving complete response (CR; no vomiting/retching or use of rescue medication) during 120 h after initiation of chemotherapy in cycle 1.. No difference in the rate of CR was noted in the casopitant group compared to the placebo group for the overall (placebo 85%, casopitant 86%, p = 0.7273), acute (placebo 96%, casopitant 97%), or delayed phases (placebo 85%, casopitant 86%). The average area under curve (0-∞) of casopitant after a single 90-mg IV dose was 8,390 ng h/mL. At 24 h after casopitant 90-mg IV dosing, the plasma casopitant concentration was 24% lower than the values noted in prior studies with 150 mg oral administration, and the plasma exposure of the major metabolite (GSK525060) was 18% lower.. Addition of single-dose casopitant 90 mg IV did not improve the control of CINV at any time during 120 h following initiation of oxaliplatin-based MEC. Excellent control of CINV was achieved in this study population with the combination of ondansetron and dexamethasone alone.

Topics: Aged; Antiemetics; Antineoplastic Combined Chemotherapy Protocols; Area Under Curve; Colorectal Neoplasms; Dexamethasone; Double-Blind Method; Drug Therapy, Combination; Female; Humans; Infusions, Intravenous; Male; Middle Aged; Nausea; Ondansetron; Organoplatinum Compounds; Oxaliplatin; Piperazines; Piperidines; Time Factors; Treatment Outcome; Vomiting

To determine the maximum tolerated dose (MTD) and safety, and explore efficacy and biomarkers of vandetanib with cetuximab and irinotecan in second-line metastatic colorectal cancer.. Vandetanib (an orally bioavailable VEGFR-2 and EGFR tyrosine kinases inhibitor) was combined at 100 mg, 200 mg, or 300 mg daily with standard dosed cetuximab and irinotecan (3+3 dose-escalation design). Ten patients were treated at the MTD and plasma angiogenesis biomarkers (VEGF, PlGF, bFGF, sVEGFR1, sVEGFR2, IL-1β, IL-6, IL-8, TNF-α, SDF1α) were measured before and after treatment.. Twenty-seven patients were enrolled at 4 dose levels and the MTD. Two dose-limiting toxicities (grade 3 QTc prolongation and diarrhea) were detected at 300 mg of vandetanib with cetuximab and irinotecan resulting in 200 mg being the MTD. Seven percent of patients had a partial response, 59% stable disease and 34% progressed. Median progression-free survival was 3.6 months (95% CI, 3.2-5.6) and median overall survival was 10.5 months (95% CI, 5.1-20.7). Toxicities were fairly manageable with grade 3 or 4 diarrhea being most prominent (30%). Vandetanib and cetuximab treatment induced a sustained increase in plasma PlGF and a transient decrease in plasma sVEGFR1, but no changes in plasma VEGF and sVEGFR2.. Vandetanib can be safely combined with cetuximab and irinotecan for metastatic colorectal cancer. Exploratory biomarker analyses suggest differential effects on certain plasma biomarkers for VEGFR inhibition when combined with EGFR blockade and a potential correlation between baseline sVEGFR1 and response. However, while the primary endpoint was safety, the observed efficacy raises concern for moving forward with this combination.. Clinicaltrials.gov NCT00436072.

Topics: Adult; Aged; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antineoplastic Agents; Biomarkers, Tumor; Camptothecin; Cetuximab; Colorectal Neoplasms; ErbB Receptors; Female; Humans; Irinotecan; Kaplan-Meier Estimate; Male; Maximum Tolerated Dose; Middle Aged; Neoplasm Metastasis; Piperidines; Quinazolines; Tomography, X-Ray Computed; Treatment Outcome; Vascular Endothelial Growth Factors

Vandetanib (ZACTIMA) is a once-daily oral inhibitor of vascular endothelial growth factor, epidermal growth factor and RET receptor tyrosine kinases. The safety and tolerability of vandetanib plus mFOLFOX6 was investigated in patients with advanced colorectal cancer (CRC).. Patients eligible for first- or second-line chemotherapy received once-daily oral doses of vandetanib (100 or 300 mg) plus 14-day treatment cycles of mFOLFOX6.. Seventeen patients received vandetanib 100 mg (n = 9) or 300 mg (n = 8) plus mFOLFOX6. The protocol definition of a tolerable dose (vandetanib-related dose-limiting toxicity [DLT] in less than two patients) was met in both dose cohorts, with one DLT of diarrhoea reported in each. Overall, the most common adverse events were diarrhoea, nausea and lethargy (all n = 11). There was no pharmacokinetic interaction between vandetanib and mFOLFOX6. Preliminary efficacy results included one complete response and three confirmed partial responses.. In patients with advanced CRC, once-daily vandetanib (100 or 300 mg) with mFOLFOX6 was generally well tolerated.

Topics: Aged; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Cohort Studies; Colorectal Neoplasms; Dose-Response Relationship, Drug; Female; Fluorouracil; Humans; Male; Middle Aged; Organoplatinum Compounds; Oxaliplatin; Piperidines; Quinazolines; Treatment Outcome

The safety and tolerability of vandetanib (ZACTIMA; ZD6474) plus FOLFIRI was investigated in patients with advanced colorectal cancer (CRC).. Patients eligible for first- or second-line chemotherapy received once-daily oral doses of vandetanib (100 or 300 mg) plus 14-day treatment cycles of FOLFIRI.. A total of 21 patients received vandetanib 100 mg (n = 11) or 300 mg (n = 10) + FOLFIRI. Combination therapy was well tolerated at both vandetanib dose levels. There were no DLTs in the vandetanib 100 mg cohort and one DLT of hypertension (CTCAE grade 3) in the 300 mg cohort. The most common adverse events were diarrhoea (n = 20), nausea (n = 12) and fatigue (n = 10). Two patients (one in each cohort) discontinued vandetanib due to adverse events (rash, 100 mg cohort; hypertension, 300 mg cohort). There was no apparent pharmacokinetic interaction between vandetanib and FOLFIRI. Preliminary efficacy results included two confirmed partial responses in the 100 mg cohort and 9 patients with stable disease > or =8 weeks (100 mg, n = 7; 300 mg, n = 2).. Once-daily vandetanib (100 or 300 mg) in combination with a standard FOLFIRI regimen was generally well tolerated in patients with advanced CRC.

Topics: Adenocarcinoma; Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Colorectal Neoplasms; Dose-Response Relationship, Drug; Female; Humans; Male; Middle Aged; Piperidines; Quinazolines

Flavopiridol, a synthetic flavone that inhibits cell cycle progression, has demonstrated activity in colon cancer in xenografts and in a phase I trial. We evaluated flavopiridol in a phase II trial in patients with previously untreated advanced colorectal cancer (ACRC).. Twenty chemotherapy-naïve patients with ACRC received flavopiridol at a dose of 50 mg/m(2)/day via a 72-h continuous infusion every 14 days. Response was assessed by computed tomography or magnetic resonance imaging every 8 weeks.. Twenty patients were enrolled; 19 were evaluable for toxicity and 18 for response. There were no objective responses. Five patients had stable disease lasting a median of 7 weeks. The median time to progression was 8 weeks. Median survival was 65 weeks. The principal grade 3/4 toxicities were diarrhea, fatigue and hyperglycemia, occurring in 21%, 11% and 11% of patients, respectively. Other common toxicities included anemia, anorexia and nausea/vomiting.. Flavopiridol in this dose and schedule does not have single-agent activity in patients with ACRC. Recent preclinical data suggest that flavopiridol enhances apoptosis when combined with chemotherapy. Trials that evaluate flavopiridol in combination with active cytotoxic drugs should help to define the role of this novel agent in ACRC.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Agents; Colorectal Neoplasms; Confidence Intervals; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Flavonoids; Follow-Up Studies; Humans; Infusions, Intravenous; Magnetic Resonance Imaging; Male; Maximum Tolerated Dose; Middle Aged; Neoplasm Invasiveness; Neoplasm Staging; Piperidines; Probability; Survival Analysis; Tomography, X-Ray Computed; Treatment Outcome

ras genes encode Ras proteins that are important for signal transduction in cancer cells. Farnesyl protein transferase (FPTase) is an enzyme that is responsible for a critical post-translational modification of Ras.. We report the results of a phase II trial of SCH 66336, an FPTase inhibitor, in patients with metastatic colorectal cancer. This is the first reported experience of an FPTase inhibitor in this disease. All patients were considered refractory to first- and second-line therapy. A total of 21 evaluable patients were treated with a starting dose of 200 mg b.i.d. given continuously.. The major side-effects were fatigue (grade 1 in 42%, grade 2 in 42% and grade 3 in 14%), diarrhea (grade 1 in 23% and grade 3 in 42%) and nausea (grade 2 in 16%). Elevations in serum creatinine (grade 2 or 3) were observed in 19% of patients and appeared to be related to dehydration induced by diarrhea. Significant hematological toxicity was not observed (only grade 1 thrombocytopenia in 19% and grade 2 or 3 anemia in 28%). Pharmacological studies revealed adequate mean pre-dose plasma concentrations in this group of patients on day 15 of therapy. No objective responses were observed, although stable disease was seen in three patients for several months. Administration of SCH 66336 was accompanied by gastrointestinal toxicity.. Future development of this compound cannot be recommended as monotherapy in this disease.

Topics: Administration, Oral; Adult; Aged; Aged, 80 and over; Biopsy, Needle; Colorectal Neoplasms; Dose-Response Relationship, Drug; Drug Administration Schedule; Drug Resistance; Drug Resistance, Neoplasm; Enzyme Inhibitors; Female; Fluorouracil; Follow-Up Studies; Humans; Liver Neoplasms; Lung Neoplasms; Male; Middle Aged; Neoplasm Staging; Piperidines; Pyridines; Survival Analysis; Treatment Outcome

S9788 is a new triazineaminopiperidine derivate capable of reversing multidrug resistance (MDR) in cells resistant to chemotherapeutic agents such as doxorubicin. It does not belong to a known class of MDR revertants, but its action involves the binding of P-glycoprotein. Thirty-eight evaluable patients with advanced colorectal or renal cell cancer were treated with doxorubicin alone (16 patients) followed after disease progression with combination treatment of doxorubicin plus S9788 (12 patients) or upfront with the combination of doxorubicin plus S9788 (22 patients). S9788 was given i.v. as a loading dose of 56 mg m-2 over 30 min followed by doxorubicin given at 50 mg m-2 as a bolus infusion. Thereafter, a 2-h infusion of S9788 was administered at escalating doses ranging from 24 to 120 mg m-2 in subsequent cohorts of 4-10 patients. Pharmacokinetic analysis demonstrated that concentrations of S9788 that are known to reverse MDR in vitro were achieved in patients at non-toxic doses. Compared with treatment with doxorubicin alone, treatment with the combination of doxorubicin and S9788 produced a significant increase in the occurrence of WHO grade 3-4 granulocytopenia. Treatment with S9788 was cardiotoxic as it caused a dose-dependent and reversible increase in corrected QT intervals as well as clinically non-significant arrhythmias on 24- or 48-h Holter recordings. Although clinically relevant cardiac toxicities did not occur, the study was terminated as higher doses of S9788 may increase the risk of severe cardiac arrhythmias. Twenty-nine patients treated with S9788 plus doxorubicin were evaluable for response, and one patient, who progressed after treatment with doxorubicin alone, achieved a partial response. We conclude that S9788 administered at the doses and schedule used in this study results in relevant plasma concentrations in humans and can safely be administered in combination with doxorubicin.

Topics: Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Renal Cell; Colorectal Neoplasms; Doxorubicin; Drug Resistance, Multiple; Electrocardiography; Heart; Humans; Kidney Neoplasms; Middle Aged; Piperidines; Triazines

Our previous study found that the combination of halofuginone (HF) and artemisinin (ATS) synergistically arrest colorectal cancer (CRC) cells at the G1/G0 phase of the cell cycle; however, it remains unclear whether HF-ATS induces cell death. Here we report that HF-ATS synergistically induced caspase-dependent apoptosis in CRC cells. Specifically, both

Topics: Antineoplastic Agents; Apoptosis; Artemisinins; Autophagy; Caspase 8; Caspase 9; Cell Line, Tumor; Colorectal Neoplasms; Drug Synergism; Enzyme Activation; Humans; Piperidines; Quinazolinones; Receptor Cross-Talk

Ibrutinib is a Bruton tyrosine kinase inhibitor used in the treatment of chronic lymphocytic leukemia (CLL). Panitumumab, an mAb for epidermal growth factor receptor, is used in the treatment of metastatic colorectal cancer (CRC). We wanted to present our case where we used ibrutinib and panitumumab in combination in a patient with metachronous CLL and CRC. A 58-year-old male patient with a diagnosis of CLL was receiving ibrutinib treatment and primary rectal cancer was detected. FOLFOX + panitumumab were started when metastasis was detected in the lung after neoadjuvant chemoradiotherapy for rectal cancer. The patients used ibrutinib and panitumumab in combination. There was no cumulative or unexpected toxicity due to the combination of both antineoplastic agents. The most important point to be considered in the use of combined drugs is the evaluation of drug-drug interactions. Toxic effects of the combination of ibrutinib and cetuximab have been reported in a patient with metastatic CRC. We used ibrutinib together with panitumumab in our case and we did not encounter any cumulative or unexpected side effects during the treatment.

Topics: Adenine; Colorectal Neoplasms; Humans; Leukemia, Lymphocytic, Chronic, B-Cell; Male; Middle Aged; Panitumumab; Piperidines; Protein Kinase Inhibitors; Rectal Neoplasms

Extraintestinal metastasis is the main therapeutic challenge for colorectal cancer, the third most common cancer worldwide. Various components of the tumor microenvironment, especially cancer-associated fibroblasts (CAFs), play important roles in tumor metastasis. NAMPT is often overexpressed in tumor tissues and is associated with poorer prognosis. However, the specific roles of NAMPT as well as NAD. This study sought to explore the molecular mechanism of FK866 in CAFs cell and colorectal cancer proliferation and metastasis.. The expression of NAMPT in clinical tissues were detected by immunohistochemically analysis. To investigate the role of NAMPT and NAD. NAMPT expression is significantly higher in colorectal cancer tissues, especially in metastatic cancer patients, than that in normal tissues. Inhibition of NAMPT by FK866 in CAFs decreases the expression of activity indicators (α-SMA, PDGFRβ), stemness indicators (BMI-1, OCT4), inflammatory factors and chemokines. Meanwhile, FK866 treatment inhibits the migration ability of SW480 cells co-cultured with CAFs. Finally, high-throughput sequencing reveals that PITX3 are down-regulated after NAD. Inhibition of the NAMPT-mediated NAD

Topics: Acrylamides; Cancer-Associated Fibroblasts; Colorectal Neoplasms; Humans; NAD; Piperidines; Tumor Microenvironment

The neurokinin-1 receptor (NK-1R) antagonists are approved as treatment for chemotherapy-associated nausea and vomiting in cancer patients. The emerging role of the substance P-NK-1R system in oncogenesis raises the possibility of repurposing well-tolerated NK-1R antagonists for cancer treatment. This study reports that human colorectal cancer (CRC) patients with high NK-1R expression have poor survival, and NK-1R antagonists SR140333 and aprepitant induce apoptotic cell death in CRC cells and inhibit CRC xenograft growth. This cytotoxicity induced by treatment with NK-1R antagonists is mediated by induction of endoplasmic reticulum (ER) stress. ER stress triggers calcium release, resulting in the suppression of prosurvival extracellular signal-regulated kinase (ERK)-c-Myc signaling. Along with ER calcium release, one ER stress pathway mediated by protein kinase RNA-like ER kinase (PERK) is specifically activated, leading to increased expression of proapoptotic C/EBP-homologous protein (CHOP). Moreover, NK-1R antagonists enhance the efficacy of chemotherapy by increasing the sensitivity and overcoming resistance to 5-fluorouracil in CRC cells through the induction of sustained ER stress and the consequent suppression of ERK-c-Myc signaling both in vitro and in vivo. Collectively, the findings provide novel mechanistic insights into the efficacy of NK-1R antagonists either as a single agent or in combination with chemotherapy for cancer treatment.

Topics: Animals; Antineoplastic Agents; Apoptosis; Aprepitant; Cell Line, Tumor; Colorectal Neoplasms; Drug Resistance, Neoplasm; Endoplasmic Reticulum Stress; Extracellular Signal-Regulated MAP Kinases; Humans; Mice; Mice, Nude; Neurokinin-1 Receptor Antagonists; Piperidines; Proto-Oncogene Proteins c-myc; Quinuclidines; Signal Transduction; Survival Rate; Transplantation, Heterologous

Colorectal cancer (CRC) is one of the most common malignancies worldwide and is associated with poor prognosis and high mortality. Despite advances in treatment with chemotherapy, CRC remains a major cause of drug resistance-related cancer deaths. One of the main reasons for such resistance is dysregulation of Mcl-1 expression. In this study, we identified LZT-106 as a novel kinase inhibitor that was able to bind to CDK9 with potent inhibitory ability, and indirectly regulate the expression of Mcl-1. However, different regulatory profiles were observed between LZT-106 and the well-studied CDK9 inhibitor flavopiridol with regards to Mcl-1 inhibition. Via Western blotting, real-time PCR and immunoprecipitation, we confirmed that LZT-106 was also able to target GSK-3β signaling and facilitate the degradation of Mcl-1. And LZT-106 was shown to synergize with ABT-199 to induce apoptosis even in the RKO cell line that overexpressed Mcl-1. Finally, LZT-106 significantly inhibited tumor growth in a xenograft mouse model with minimal toxicity. Overall, our findings suggest that LZT-106 is a promising candidate drug for the treatment of patients with CRC.

Topics: Animals; Antineoplastic Agents; Apoptosis; Apoptosis Regulatory Proteins; Bridged Bicyclo Compounds, Heterocyclic; Cell Line; Cell Line, Tumor; Colorectal Neoplasms; Cyclin-Dependent Kinase 9; Down-Regulation; Flavonoids; Glycogen Synthase Kinase 3 beta; HCT116 Cells; HEK293 Cells; HT29 Cells; Humans; Mice; Mice, Inbred BALB C; Mice, Nude; Myeloid Cell Leukemia Sequence 1 Protein; Piperidines; Protein Kinase Inhibitors; Signal Transduction; Sulfonamides

Despite the advancements in new therapies for colorectal cancer (CRC), chemotherapy still constitutes the mainstay of the medical treatment. For this reason, new strategies to increase the efficacy of chemotherapy are desirable. Poly-ADP-Ribose Polymerase inhibitors (PARPi) have shown to increase the activity of DNA damaging chemotherapeutics used in the treatment of CRC, however previous clinical trials failed to validate these results and pointed out dose-limiting toxicities that hamper the use of such combinations in unselected CRC patients. Nevertheless, in these studies little attention was paid to the mutational status of homologous recombination repair (HRR) genes.. We tested the combination of the PARPi niraparib with either 5-fluorouracil, oxaliplatin or irinotecan (SN38) in a panel of 12 molecularly annotated CRC cell lines, encompassing the 4 consensus molecular subtypes (CMSs). Synergism was calculated using the Chou-Talalay method for drug interaction. A correlation between synergism and genetic alterations in genes involved in homologous recombination (HR) repair was performed. We used clonogenic assays, mice xenograft models and patient-derived 3D spheroids to validate the results. The induction of DNA damage was studied by immunofluorescence.. We showed that human CRC cell lines, as well as patient-derived 3D spheroids, harboring pathogenic ATM mutations are significantly vulnerable to PARPi/chemotherapy combination at low doses, regardless of consensus molecular subtypes (CMS) and microsatellite status. The strongest synergism was shown for the combination of niraparib with irinotecan, and the presence of ATM mutations was associated to a delay in the resolution of double strand breaks (DSBs) through HRR and DNA damage persistence.. This work demonstrates that a numerically relevant subset of CRCs carrying heterozygous ATM mutations may benefit from the combination treatment with low doses of niraparib and irinotecan, suggesting a new potential approach in the treatment of ATM-mutated CRC, that deserves to be prospectively validated in clinical trials.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Cell Line, Tumor; Colorectal Neoplasms; Female; Humans; Indazoles; Irinotecan; Mice; Mice, Nude; Mutation; Piperidines

Recently developed molecularly targeted therapies such as EGFR inhibitors have notably improved the prognosis of patients with cancer. However, patients with KRAS and BRAF mutations do not currently benefit from these therapies. Here, we aimed to examine potential effects of crenolanib as a new molecularly targeted therapy in colorectal cancer. We used multiple colorectal cancer cell lines to investigate the growth-inhibitory effect of crenolanib and its effect in combination with other cytotoxic agents. Primary cultures of patient-derived organoids (PDO), a model that reflects the heterogeneity of clinical colorectal cancer, were used to further validate the effects of crenolanib. Unlike cetuximab, crenolanib remarkably suppressed ERK and AKT/mTOR pathways in HT29 cells with BRAF mutation and in HCT116 cells with KRAS mutation with corresponding growth-suppressing effects. Additive or synergistic effects were observed in treatments with combination of crenolanib and other cytotoxic drugs. Moreover, crenolanib suppressed the expression of stem cell markers, such as OCT4, NANOG, and SOX2. These observations were substantiated in seven PDOs with KRAS mutation and two PDOs without KRAS/BRAF mutations, with crenolanib suppressing the growth of all PDOs regardless of their KRAS mutation status. Furthermore, crenolanib abrogated PDGF- and TGFβ-induced increase of OCT4-positive cells in PDOs. Together, these findings suggest that crenolanib may have clinical utility for patients with colorectal cancer, especially patients with KRAS/BRAF mutations. IMPLICATIONS: These findings indicate that crenolanib can be a useful target agent for patients with colorectal cancer, especially patients with KRAS/BRAF mutations.

Topics: Animals; Antineoplastic Agents; Benzimidazoles; Colorectal Neoplasms; Humans; Mice; Mice, Inbred NOD; Organoids; Piperidines; Proto-Oncogene Proteins B-raf; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins p21(ras); Signal Transduction

Topics: Aged; Aminopyridines; Anaplastic Lymphoma Kinase; Antineoplastic Agents; Carbazoles; Colorectal Neoplasms; Crizotinib; Female; Gene Rearrangement; Humans; Lactams; Neoplasm Metastasis; Piperidines; Pyrazoles; Treatment Outcome

BZD9L1 was previously described as a SIRT1/2 inhibitor with anti-cancer activities in colorectal cancer (CRC), either as a standalone chemotherapy or in combination with 5-fluorouracil. BZD9L1 was reported to induce apoptosis in CRC cells; however, the network of intracellular pathways and crosstalk between molecular players mediated by BZD9L1 is not fully understood. This study aimed to uncover the mechanisms involved in BZD9L1-mediated cytotoxicity based on previous and new findings for the prediction and identification of related pathways and key molecular players. BZD9L1-regulated candidate targets (RCTs) were identified using a range of molecular, cell-based and biochemical techniques on the HCT 116 cell line. BZD9L1 regulated major cancer pathways including Notch, p53, cell cycle, NFκB, Myc/MAX, and MAPK/ERK signalling pathways. BZD9L1 also induced reactive oxygen species (ROS), regulated apoptosis-related proteins, and altered cell polarity and adhesion profiles. In silico analyses revealed that most RCTs were interconnected, and were involved in the modulation of catalytic activity, metabolism and transcription regulation, response to cytokines, and apoptosis signalling pathways. These RCTs were implicated in p53-dependent apoptosis pathway. This study provides the first assessment of possible associations of molecular players underlying the cytotoxic activity of BZD9L1, and establishes the links between RCTs and apoptosis through the p53 pathway.

Topics: Apoptosis; Benzimidazoles; Cell Adhesion; Cell Polarity; Colorectal Neoplasms; Gene Expression Regulation, Neoplastic; Gene Ontology; HCT116 Cells; Humans; Neurites; Piperidines; Protein Interaction Maps; Reactive Oxygen Species; Signal Transduction; Sirtuins; Spheroids, Cellular

The role and mechanism of the nicotinamide adenine dinucleotide (NAD. Real-time PCR, immunohistochemistry, western blotting, and analyses of datasets from Oncomine and Gene Expression Omnibus were conducted to assess the expression of NAMPT at the mRNA and protein levels in colorectal cancer. The Kaplan Meier plotter online tool was used to evaluate the prognostic role of NAMPT. Knockdown of NAMPT was performed to assess the role of NAMPT in colorectal cancer cell proliferation and tumorigenesis both in vitro and in vivo. Overexpression of NAMPT was used to evaluate impact of NAMPT on colorectal cancer cell proliferation in vitro. NAD. Our study indicated that the inhibition of NAMPT decreased proliferation capacity of colorectal cancer cells both in vitro and in vivo. Conversely, overexpression of NAMPT could promote cell proliferation in vitro. NAMPT inhibition induced β-catenin degradation by increasing Axin expression levels; this resulted in the inhibition of Wnt/β-catenin signaling and cell proliferation in colorectal cancer. The addition of nicotinamide mononucleotide, the enzymatic product of NAMPT, effectively reversed β-catenin protein degradation and inhibited growth. Similarly, the knockdown of Axin also decreased the cell death induced by the inhibition of NAMPT. In addition, we showed that colorectal cancer tissues harbored significantly higher levels of NAMPT than the levels harbored by paired normal tissues, especially in colorectal cancer stages I and II. And the overexpression of NAMPT was associated with unfavorable survival results.. Our findings reveal that NAMPT plays an important role in colorectal cancer proliferation via Wnt/β-catenin pathway, which could have vital implications for the diagnosis, prognosis and treatment of colorectal cancer.

Topics: Acrylamides; Adenomatous Polyposis Coli Protein; Animals; Axin Protein; Cell Line, Tumor; Cell Movement; Cell Proliferation; Colorectal Neoplasms; Cytokines; Female; Gene Knockdown Techniques; Humans; Mice, Inbred BALB C; Mice, Nude; Models, Biological; Mutation; NAD; Neoplasm Invasiveness; Nicotinamide Phosphoribosyltransferase; Piperidines; Prognosis; Wnt Signaling Pathway

Cancer metastasis is the primary cause of death in patients diagnosed with colorectal cancer. Piperine, an active nontoxic ingredient in pepper, has potent anti-inflammatory and anti-cancer properties. However, little is known about the anti-migratory and anti-invasive effects of piperine on colorectal cancer. We demonstrated piperine inhibited the migration and invasion of colorectal cancer cells. Then, we found piperine reversed the biomarker expression of epithelial-to-mesenchymal transition (EMT), and suppressed the EMT regulator Snail. Furthermore, signal transducers and activators of transcription 3 (STAT3) was downregulated by piperine. Finally, STAT3 inhibitors were applied to observe the role of STAT3 in colorectal cancer migration, invasion and EMT. Collectively, piperine inhibits colorectal cancer migratory and invasive capacities through STAT3/Snail mediated EMT. Therefore, piperine could be applied as a possible therapeutic regimen for the prevention of colorectal cancer metastasis.

Topics: Alkaloids; Benzodioxoles; Cell Line, Tumor; Cell Movement; Colorectal Neoplasms; Epithelial-Mesenchymal Transition; Humans; Piperidines; Polyunsaturated Alkamides; Snail Family Transcription Factors; STAT3 Transcription Factor

Mitogen-activated protein kinase (MAPK) kinase (MEK) is an integral component of the RAS pathway and a therapeutic target in RAS-driven cancers. Although tumor responses to MEK inhibition are rarely durable, MEK inhibitors have shown substantial activity and durable tumor regressions when combined with systemic immunotherapies in preclinical models of RAS-driven tumors. MEK inhibitors have been shown to potentiate anti-tumor T cell immunity, but little is known about the effects of MEK inhibition on other immune subsets, including B cells. We show here that treatment with a MEK inhibitor reduces B regulatory cells (Bregs) in vitro, and reduces the number of Bregs in tumor draining lymph nodes in a colorectal cancer model in vivo. MEK inhibition does not impede anti-tumor humoral immunity, and B cells contribute meaningfully to anti-tumor immunity in the context of MEK inhibitor therapy. Treatment with a MEK inhibitor is associated with improved T cell infiltration and an enhanced response to anti-PD1 immunotherapy. Together these data indicate that MEK inhibition may reduce Bregs while sparing anti-tumor B cell function, resulting in enhanced anti-tumor immunity.

Topics: Animals; Azetidines; B-Lymphocytes, Regulatory; Cell Line, Tumor; Colonic Neoplasms; Colorectal Neoplasms; Extracellular Signal-Regulated MAP Kinases; Genes, ras; Humans; Immunotherapy; Male; Mice; Mice, Inbred BALB C; Mitogen-Activated Protein Kinase Kinases; Piperidines; Protein Kinase Inhibitors; Proto-Oncogene Proteins B-raf; Xenograft Model Antitumor Assays

Colorectal cancer (CRC) is the third most common malignancy, and the metabolic properties of CRC cells include enhanced aerobic glycolysis (the Warburg effect). Nicotinamide phosphoribosyl transferase (NAMPT) is one of the crucial enzymes that regulate the activity of nicotinamide adenine dinucleodinucleotide dependent enzymes. Targeting NAMPT is a potential method of CRC therapy. Nevertheless, the underlying clinical implications and regulatory mechanisms of NAMPT in CRC remain unclear. In this study, we showed that NAMPT protein expression was increased in subjects with rectal localization compared with those with colon localization, and NAMPT was a poor prognostic marker for the overall survival rate in patients with CRC. In addition, the NAMPT inhibitor FK866 or lentivirus-mediated silencing induced CRC cell growth inhibition. Mechanistically, NAMPT regulated Sirt1 and P53 expression and induced G0/G1 cell cycle arrest, along with the upregulation of downstream p21 and downregulation of cyclin D1, cyclin E1, and cyclin E2 expression. FK866 administration or knockdown of NAMPT induced CRC cell apoptosis via upregulation of caspase-3. In conclusion, NAMPT regulated Sirt1/P53 signaling during CRC cell growth and warrants further investigation for clinical administration in CRC.

Topics: Acrylamides; Antineoplastic Agents; Apoptosis; Cell Cycle Checkpoints; Cell Proliferation; Colorectal Neoplasms; Cytokines; Enzyme Inhibitors; Female; Gene Expression Regulation, Enzymologic; Gene Expression Regulation, Neoplastic; HCT116 Cells; Humans; Male; Middle Aged; Nicotinamide Phosphoribosyltransferase; Piperidines; Signal Transduction; Sirtuin 1; Tumor Suppressor Protein p53

Cancer cells' resistance to drugs remains an important problem affecting cancer treatment strategies. We previously studied the nicotinamide phosphoribosyltransferase (NAMPT) inhibitor FK866's resistance mechanisms in the human colorectal cancer HCT116 cells. We established an acquired FK866-resistant cell line, HCT116R

Topics: Acrylamides; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Cisplatin; Colorectal Neoplasms; Cytokines; DNA Damage; Drug Resistance, Neoplasm; Enzyme Inhibitors; Exome Sequencing; Fluorouracil; Gamma Rays; Gene Expression Regulation, Neoplastic; Genomics; HCT116 Cells; Humans; Nicotinamide Phosphoribosyltransferase; Piperidines

Topics: Antibodies, Monoclonal, Humanized; Azetidines; B7-H1 Antigen; Colorectal Neoplasms; Humans; Phenylurea Compounds; Piperidines; Pyridines

Despite advances in targeted anticancer therapies, there are still no small-molecule-based therapies available that specifically target colorectal cancer (CRC) development and progression, the second leading cause of cancer deaths. We previously disclosed the discovery of truncating adenomatous polyposis coli (APC)-selective inhibitor 1 (TASIN-1), a small molecule that specifically targets colorectal cancer cells lines with truncating mutations in the adenomatous polyposis coli (APC) tumor suppressor gene through inhibition of cholesterol biosynthesis. Here, we report a medicinal chemistry evaluation of a collection of TASIN analogues and activity against colon cancer cell lines and an isogenic cell line pair reporting on the status of APC-dependent selectivity. A number of potent and selective analogues were identified, including compounds with good metabolic stability and pharmacokinetic properties. The compounds reported herein represent a first-in-class genotype-selective series that specifically target apc mutations present in the majority of CRC patients and serve as a translational platform toward a targeted therapy for colon cancer.

Topics: Adenomatous Polyposis Coli; Adenomatous Polyposis Coli Protein; Animals; Antineoplastic Agents; Cell Line, Tumor; Colorectal Neoplasms; Drug Design; Drug Discovery; Female; Gene Expression Regulation, Neoplastic; Humans; Mice; Mice, Inbred ICR; Mutation; Piperidines; Protein Binding; Structure-Activity Relationship; Sulfonamides

Platelet‑derived growth factor receptor‑β (PDGFR‑β) in epithelial tumors is mainly expressed by stromal cells. High expression of PDGFR‑β has been related to poor prognosis in several cancers, however its significance in colorectal cancer (CRC) remains unknown. The present study aimed to clarify the prognostic impact of PDGFR‑β in CRC patients. The study included 194 patients who underwent surgery for CRC. PDGFR‑β expression was examined by real‑time reverse transcription‑polymerase chain reaction and immunohistochemistry and the expression levels were correlated with various clinical parameters. The biological significance was evaluated by knockdown experiments in CRC cell lines and the specific PDGFR inhibitor, crenolanib. PDGFR‑β mRNA and protein expression levels were positively correlated with each other. Low PDGFR‑β expression was associated with significantly better disease‑free survival after curative surgical resection, than high PDGFR‑β expression, according to univariate and multivariate analyses. The assessment of PDGFR‑β knockdown in two cell lines revealed that small interfering RNA (siRNA) inhibition resulted in statistically significant reductions in cell growth and invasion. PDGFR inhibitor suppressed CRC cell proliferation in vitro in a dose‑dependent manner. In conclusion, PDGFR‑β expression was a risk factor for recurrence in patients with CRC and PDGFR inhibitor may be a useful therapeutic agent for CRC.

Topics: Antineoplastic Agents; Benzimidazoles; Cell Line, Tumor; Cell Proliferation; Colorectal Neoplasms; Female; Gene Expression Regulation, Neoplastic; HCT116 Cells; Humans; Male; Piperidines; Prognosis; Receptor, Platelet-Derived Growth Factor beta; Recurrence; Survival Analysis; Up-Regulation

There is increasing interest in developing and applying DNA repair inhibitors in cancer treatment to augment the efficacy of radiation and conventional genotoxic chemotherapy. However, targeting the inhibitor is required to avoid reducing the repair capacity of normal tissue. The aim of this study was to develop nanodelivery systems for the encapsulation of novel imidopiperidine-based inhibitors of the DNA 3'-phosphatase activity of polynucleotide kinase/phosphatase (PNKP), a DNA repair enzyme that plays a critical role in rejoining DNA single- and double-strand breaks. For this purpose, newly identified hit compounds with potent PNKP inhibitory activity, imidopiperidines A12B4C50 and A83B4C63 were encapsulated in polymeric micelles of different poly(ethylene oxide)- b-poly(ε-caprolactone) (PEO- b-PCL)-based structures. Our results showed efficient loading of A12B4C50 and A83B4C63 in PEO- b-PCLs with pendent carboxyl and benzyl carboxylate groups, respectively, and relatively slow release over 24 h. Both free and encapsulated inhibitors were able to sensitize HCT116 cells to radiation and the topoisomerase I poison, irinotecan. In addition, the encapsulated inhibitors were capable of inducing synthetic lethalilty in phosphatase and tensin homologue (PTEN)-deficient cells. We also established the validity of the peptide GE11 as a suitable ligand for active targeted delivery of nanoencapsulated drugs to colorectal cancer cells overexpressing epidermal growth factor receptor (EGFR). Our results show the potential of nanoencapsulated inhibitors of PNKP as either mono or combined therapeutic agents for colorectal cancer.

Topics: Chemoradiotherapy; Colorectal Neoplasms; DNA Repair; DNA Repair Enzymes; Drug Compounding; Drug Resistance, Neoplasm; HCT116 Cells; Humans; Irinotecan; Micelles; Nanocapsules; Phosphotransferases (Alcohol Group Acceptor); Piperidines; Radiation, Ionizing; Synthetic Lethal Mutations

Mutations in the Ras/Raf/MEK/ERK pathway are detected in 50% of colorectal cancer cases and play a crucial role in cancer development and progression. Cobimetinib is a MEK inhibitor approved for the treatment of advanced melanoma and inhibits the cell viability of other types of cancer cells.. HCT116 colorectal cancer cells were treated with cobimetinib, and MTT assay, colony formation assay, and flow cytometry were used to evaluate cell viability, cell cycle, and apoptosis, respectively. The expression of genes associated with the cell cycle and apoptosis were evaluated by quantitative real-time PCR and western blotting. To explore use of cobimetinib in colorectal cancer treatment and further understand its mechanisms, RNA-seq technology was used to identify differentially expressed genes (DEGs) between cobimetinib-treated and untreated HCT116 cells. Furthermore, we compared these DEGs with Gene Expression Omnibus data from colorectal cancer tissues and normal colonic epithelial tissues.. We found that cobimetinib not only inhibited cell proliferation but also induced G1 phase arrest and apoptosis in HCT116 colorectal cancer cells, suggesting that cobimetinib may useful in colorectal cancer therapy. After cobimetinib treatment, 3,495 DEGs were obtained, including 2,089 upregulated genes and 1,406 downregulated genes, and most of these DEGs were enriched in the cell cycle, DNA replication, and DNA damage repair pathways. Our results revealed that some genes with high expression in colorectal cancer tissues were downregulated by cobimetinib in HCT116 cells, including CCND1, E2F1, CDC25C, CCNE2, MYC, and PCNA. These genes have vital roles in DNA replication and the cell cycle. Furthermore, genes with low expression in colorectal cancer tissues were upregulated by cobimetinib, including PRKCA, PI3K, RTK, and PKC. Based on our results, the PKC and PI3K pathways were activated after cobimetinib treatment, and inhibition of these two pathways can increase the cytotoxicity of cobimetinib in HCT116 cells. Notably, cobimetinib appeared to enhance the efficacy of 5-fluorouracil (5-FU) by decreasing TYMS expression, high expression of which is responsible for 5-FU resistance in colorectal cancer.. Our results suggest the potential use of cobimetinib in colorectal cancer therapy.

Topics: Apoptosis; Azetidines; Cell Line, Tumor; Colorectal Neoplasms; Cyclin D1; Cyclin-Dependent Kinase Inhibitor p21; Down-Regulation; Drug Resistance, Neoplasm; Fluorouracil; G1 Phase Cell Cycle Checkpoints; HCT116 Cells; Humans; MAP Kinase Kinase Kinases; Phosphatidylinositol 3-Kinases; Piperidines; Protein Kinase Inhibitors; Thymidylate Synthase; Tumor Suppressor Protein p53; Up-Regulation

Neurokinin1 (NK1) receptor has played a vital role in the development of tumor. However, NKP608 as a NK1 receptor antagonist whether has the effect of the resistance of colorectal cancer is still unclear. Thereby, in this study, we investigated the role of NKP608 on human colorectal cancer and explored the underlying mechanism.. The cell proliferation of colorectal cancer cells was detected by cell counting kit-8 (CCK8) assay, cell migration and invasion were assessed by transwell assay, the apoptotic ratio of cells was assessed by Annexin V-fluorescein isothiocyanate/propidium iodide stained and flow cytometry. The involvement of molecular mechanisms was examined by western blot.. In this study, we found that NKP608 inhibited the proliferation, migration/invasion of HCT116 cells. In addition, NKP608 reduced expressions of Wnt-3a, β-catenin, Cyclin D1, and (vascular endothelial growth factor) VEGF while induced expression of E-Cadherin. Furthermore, flow cytometry analyzed that NKP608 induced apoptosis of HCT116 cells, consistently, western blotting detecting of apoptosis-related proteins revealed that NKP608 downregulated Bcl-2 while upregulated Bax and Active-Caspase-3.. Taken together, our results demonstrated that NKP608 inhibited colorectal cancer cell proliferation, migration and invasion via suppressing the Wnt/β-catenin signaling pathway. Therefore, NKP608 might represent a promising therapeutic agent in the treatment of colorectal cancer.

Topics: Blotting, Western; Cell Line, Tumor; Cell Movement; Cell Proliferation; Colorectal Neoplasms; Down-Regulation; Flow Cytometry; HCT116 Cells; Humans; Neurokinin-1 Receptor Antagonists; Piperidines; Quinolines; Wnt Signaling Pathway

The endocannabinoid system has previously been shown to play a role in the permeability and inflammatory response of the human gut. The goal of our study was to determine the effects of endogenous anandamide (AEA) and 2-arachidonoyl glycerol (2-AG) on the permeability and inflammatory response of intestinal epithelium under normal, inflammatory, and hypoxic conditions. Human intestinal mucosa was modeled using Caco-2 cells. Human tissue was collected from planned colorectal resections. Accumulation of AEA and 2-AG was achieved by inhibiting their metabolizing enzymes URB597 (a fatty acid amide hydrolase inhibitor) and JZL184 (a monoacylglycerol lipase inhibitor). Inflammation and ischemia were simulated with TNF-α and IFN-γ and oxygen deprivation. Permeability changes were measured by transepithelial electrical resistance. The role of the CB

Topics: Amidohydrolases; Arachidonic Acids; Benzamides; Benzodioxoles; Caco-2 Cells; Carbamates; Colorectal Neoplasms; Cytokines; Electric Impedance; Endocannabinoids; Gene Expression Regulation; Glycerides; Humans; Inflammation; Intestinal Mucosa; Intestines; Monoacylglycerol Lipases; Oxygen Consumption; Permeability; Piperidines; Polyunsaturated Alkamides; Receptor, Cannabinoid, CB1; Tissue Culture Techniques

Autophagy has a key role in metabolism and impacts on tumorigenesis. Our previous study found that halofuginone (HF) exerts anticancer activity in colorectal cancer (CRC) by downregulating Akt/mTORC1 (mechanistic target of rapamycin complex 1) signaling pathway. But whether and how HF regulates autophagy and metabolism to inhibit cancer growth remains an open question. Here, we unveil that HF activates ULK1 by downregulation of its phosphorylation site at Ser757 through Akt/mTORC1 signaling pathway, resulting in induction of autophagic flux under nutrient-rich condition. On the other hand, HF inactivates ULK1 by downregulation of its phosphorylation sites at Ser317 and Ser777 through LKB1/AMPK signaling pathway, resulting in autophagic inhibition under nutrient-poor condition. Furthermore, Atg7-dependent autophagosome formation is also induced under nutrient-rich condition or blocked in nutrient-poor environment, respectively, upon HF treatment. More interestingly, we also found that HF inhibits glycolysis under nutrient-rich condition, whereas inhibits gluconeogenesis under nutrient-poor condition in an Atg7-dependent manner, suggesting that autophagy has a pivotal role of glucose metabolism upon HF treatment. Subsequent studies showed that HF treatment retarded tumor growth in xenograft mice fed with either standard chow diet or caloric restriction through dual regulation of autophagy in vivo. Together, HF has a dual role in autophagic modulation depending on nutritional conditions for anti-CRC.

Topics: AMP-Activated Protein Kinase Kinases; AMP-Activated Protein Kinases; Animals; Autophagy; Cell Line, Tumor; Colorectal Neoplasms; Humans; Male; Mechanistic Target of Rapamycin Complex 1; Mice; Mice, Inbred BALB C; Mice, Nude; Piperidines; Protein Kinases; Protein Serine-Threonine Kinases; Proto-Oncogene Proteins c-akt; Quinazolinones; Signal Transduction; Xenograft Model Antitumor Assays

AKT is often hyper-activated in human colorectal cancers (CRC). This current study evaluated the potential anti-CRC activity by AT7867, a novel AKT and p70S6K1 (S6K1) dual inhibitor. We showed that AT7867 inhibited survival and proliferation of established (HT-29, HCT116 and DLD-1 lines) and primary human CRC cells. Meanwhile, it provoked caspase-dependent apoptosis in the CRC cells. Molecularly, AT7867 blocked AKT-S6K1 activation in CRC cells. Restoring AKT-S6K1 activation, via expression of a constitutively-active AKT1 ("ca-AKT1"), only partially attenuated AT7867-induced HT-29 cell death. Further studies demonstrated that AT7867 inhibited sphingosine kinase 1 (SphK1) activity to promote pro-apoptotic ceramide production in HT-29 cells. Such effects by AT7867 were independent of AKT inhibition. AT7867-indued ceramide production and subsequent HT-29 cell apoptosis were attenuated by co-treatment of sphingosine-1-phosphate (S1P), but were potentiated with the glucosylceramide synthase (GCS) inhibitor PDMP. In vivo, intraperitoneal injection of AT7867 inhibited HT-29 xenograft tumor growth in nude mice. AKT activation was also inhibited in AT7867-treated HT-29 tumors. Together, the preclinical results suggest that AT7867 inhibits CRC cells via AKT-dependent and -independent mechanisms.

Topics: Animals; Apoptosis; Cell Line, Tumor; Colorectal Neoplasms; Enzyme Activation; Humans; Mice; Mice, Nude; Phosphotransferases (Alcohol Group Acceptor); Piperidines; Proto-Oncogene Proteins c-akt; Pyrazoles; Ribosomal Protein S6 Kinases, 70-kDa; Xenograft Model Antitumor Assays

Monoacylglycerol lipase (MAGL) is involved in the degradation of triacylglycerol. Previous studies have demonstrated that MAGL regulates tumor growth and metastasis via fatty acid networks, and is associated with colorectal cancer. JZL184 is a MAGL inhibitor, which in the present study was administered to colorectal cancer cell lines, resulting in decreased tumor proliferation, increased apoptosis and increased tumor cell sensitivity to 5-fluorouracil. B‑cell lymphoma 2 (Bcl‑2) and Bcl‑2‑associated X protein (Bax) are key proteins in apoptosis. The expression levels of Bcl‑2/Bax were determined in colorectal cancer cell lines following JZL184 administration, and it was observed that the mRNA and protein expression levels of Bcl‑2 were decreased, whereas the expression levels of Bax were increased. These results indicated that JZL184 may induce tumor cell apoptosis by regulating the expression of Bcl‑2 and Bax. Epithelial-mesenchymal transition (EMT) is closely associated with metastasis. Administration of JZL184 in various malignant colorectal cancer cell lines suppressed migration and altered the expression of EMT markers; E‑cadherin was increased, whereas the expression levels of vimentin and zinc finger protein SNAI1 were decreased. These results suggested that JZL184 was able to regulate the EMT process, in order to control the migration of colorectal cancer cells, particularly in tumors with a stronger metastatic capability. Therefore, in colorectal cancer, MAGL may be considered a potential therapeutic target and JZL184 may be a possible therapeutic agent.

Topics: Antineoplastic Agents; Apoptosis; bcl-2-Associated X Protein; Benzodioxoles; Cell Movement; Cell Proliferation; Colorectal Neoplasms; Drug Screening Assays, Antitumor; HCT116 Cells; Humans; Monoacylglycerol Lipases; Piperidines; Proto-Oncogene Proteins c-bcl-2

Mutations in the adenomatous polyposis coli (APC) gene are common in colorectal cancer (CRC), and more than 90% of those mutations generate stable truncated gene products. We describe a chemical screen using normal human colonic epithelial cells (HCECs) and a series of oncogenically progressed HCECs containing a truncated APC protein. With this screen, we identified a small molecule, TASIN-1 (truncated APC selective inhibitor-1), that specifically kills cells with APC truncations but spares normal and cancer cells with wild-type APC. TASIN-1 exerts its cytotoxic effects through inhibition of cholesterol biosynthesis. In vivo administration of TASIN-1 inhibits tumor growth of CRC cells with truncated APC but not APC wild-type CRC cells in xenograft models and in a genetically engineered CRC mouse model with minimal toxicity. TASIN-1 represents a potential therapeutic strategy for prevention and intervention in CRC with mutant APC.

Topics: Adenomatous Polyposis Coli Protein; Animals; Cell Proliferation; Cholesterol; Colonic Neoplasms; Colorectal Neoplasms; Female; Genes, Tumor Suppressor; HCT116 Cells; Humans; Male; Mice; Mice, Nude; Molecular Targeted Therapy; Mutation; Piperidines; Sterol Regulatory Element Binding Protein 2; Sulfonamides; Transgenes; Xenograft Model Antitumor Assays

Topics: Activins; Animals; Antibodies, Neoplasm; Antineoplastic Agents; Autoantibodies; B-Cell Activating Factor; B-Lymphocytes; Cell Line, Tumor; Cell Proliferation; Colorectal Neoplasms; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Endoplasmic Reticulum Chaperone BiP; Epoxide Hydrolases; Female; Gene Expression; Immunity, Humoral; Immunologic Factors; Mice, Inbred BALB C; Mice, Nude; Neoplasm Transplantation; Phenyl Ethers; Piperidines; Signal Transduction; Tumor Burden

Topics: Adenomatous Polyposis Coli Protein; Animals; Antineoplastic Agents; Colonic Polyps; Colorectal Neoplasms; Drug Design; Humans; Mutation; Piperidines; Sulfonamides

The Akt/mTORC1 pathway plays a central role in the activation of Warburg effect in cancer. Here, we present for the first time that halofuginone (HF) treatment inhibits colorectal cancer (CRC) growth both in vitro and in vivo through regulation of Akt/mTORC1 signaling pathway. Halofuginone treatment of human CRC cells inhibited cell proliferation, induced the generation of reactive oxygen species and apoptosis. As expected, reduced level of NADPH was also observed, at least in part due to inactivation of glucose-6-phosphate dehydrogenase in pentose phosphate pathway upon HF treatment. Given these findings, we further investigated metabolic regulation of HF through Akt/mTORC1-mediated aerobic glycolysis and found that HF downregulated Akt/mTORC1 signaling pathway. Moreover, metabolomics delineated the slower rates in both glycolytic flux and glucose-derived tricarboxylic acid cycle flux. Meanwhile, both glucose transporter GLUT1 and hexokinase-2 in glycolysis were suppressed in CRC cells upon HF treatment, to support our notion that HF regulates Akt/mTORC1 signaling pathway to dampen glucose uptake and glycolysis in CRC cells. Furthermore, HF retarded tumor growth in nude mice inoculated with HCT116 cells, showing the anticancer activity of HF through metabolic regulation of Akt/mTORC1 in CRC.

Topics: Animals; Antineoplastic Agents; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Cell Survival; Colorectal Neoplasms; Female; Glucose; Glucose Transporter Type 1; Glycolysis; HCT116 Cells; Hexokinase; Humans; In Situ Nick-End Labeling; Lipids; Mechanistic Target of Rapamycin Complex 1; Medicine, Chinese Traditional; Mice; Mice, Inbred BALB C; Mice, Nude; Multiprotein Complexes; Pentose Phosphate Pathway; Piperidines; Protein Synthesis Inhibitors; Proto-Oncogene Proteins c-akt; Quinazolinones; Reactive Oxygen Species; Signal Transduction; TOR Serine-Threonine Kinases

Colorectal cancer (CRC) is in the third place of the most common cancers. Certain risk factors can increase the development of CRC, including diet and inheritance. Several studies have shown that there is a potential link between obesity and CRC. Adipose tissue is known to be a largest endocrine organ in the body, with the ability to produce various cytokines including adiponectin. Two types of adiponectin receptor, AdipoR1 and AdipoR2, have been detected in various cancer tissues such as CRC. There is mounting evidence that AdipoR1 signaling occurs mainly through 5' AMP-activated protein kinase (AMPK) and adiponectin inhibits colorectal cancer cell growth via activation of AMPK, thereby suppression of the mammalian target of rapamycin (mTOR) pathway. Thus, adiponectin replacement-based therapies may represent a novel approach in CRC cell growth inhibition in early stages. AdipoRon is an adiponectin-like synthetic small molecule that activated both adiponectin receptors 1 and 2. We hypothesize that AdipoRon has antiproliferative effects of adiponectin and may suppress the CRC cell growth. With clarification of this drug's role in CRC, it can be used as chemoprevention in patients at risk of developing the disease.

Topics: Adiponectin; AMP-Activated Protein Kinases; Colorectal Neoplasms; Humans; Piperidines; Receptors, Adiponectin; Signal Transduction

Most colorectal cancers (CRC) are initiated by mutations of APC, leading to increased β-catenin-mediated signaling. However, continued requirement of Wnt/β-catenin signaling for tumor progression in the context of acquired KRAS and other mutations is less well-established. To attenuate Wnt/β-catenin signaling in tumors, we have developed potent and specific small-molecule tankyrase inhibitors, G007-LK and G244-LM, that reduce Wnt/β-catenin signaling by preventing poly(ADP-ribosyl)ation-dependent AXIN degradation, thereby promoting β-catenin destabilization. We show that novel tankyrase inhibitors completely block ligand-driven Wnt/β-catenin signaling in cell culture and display approximately 50% inhibition of APC mutation-driven signaling in most CRC cell lines. It was previously unknown whether the level of AXIN protein stabilization by tankyrase inhibition is sufficient to impact tumor growth in the absence of normal APC activity. Compound G007-LK displays favorable pharmacokinetic properties and inhibits in vivo tumor growth in a subset of APC-mutant CRC xenograft models. In the xenograft model most sensitive to tankyrase inhibitor, COLO-320DM, G007-LK inhibits cell-cycle progression, reduces colony formation, and induces differentiation, suggesting that β-catenin-dependent maintenance of an undifferentiated state may be blocked by tankyrase inhibition. The full potential of the antitumor activity of G007-LK may be limited by intestinal toxicity associated with inhibition of Wnt/β-catenin signaling and cell proliferation in intestinal crypts. These results establish proof-of-concept antitumor efficacy for tankyrase inhibitors in APC-mutant CRC models and uncover potential diagnostic and safety concerns to be overcome as tankyrase inhibitors are advanced into the clinic.

Topics: Animals; Axin Protein; beta Catenin; Cell Line, Tumor; Cell Proliferation; Colorectal Neoplasms; Enzyme Inhibitors; Genes, APC; Humans; Mice; Mutation; Piperidines; Spheroids, Cellular; Sulfones; Tankyrases; Triazoles; Wnt Signaling Pathway; Xenograft Model Antitumor Assays

The human ether-à-go-go-related gene (hERG)1 K(+) channel is upregulated in human colorectal cancer cells and primary samples. In this study, we examined the role of hERG1 in colorectal carcinogenesis using two mouse models: adenomatous polyposis coli (Apc(min/+) ) and azoxymethane (AOM)-treated mice. Colonic polyps of Apc(min/+) mice overexpressed mERG1 and their formation was reverted by the hERG1 blocker E4031. AOM was applied to either hERG1-transgenic (TG) mice, which overexpress hERG1 in the mucosa of the large intestine, or wild-type mice. A significant increase of both mucin-depleted foci and polyps in the colon of hERG1-TG mice was detected. Both the intestine of TG mice and colonic polyps of Apc(min/+) showed an upregulation of phospho-Protein Kinase B (pAkt)/vascular endothelial growth factor (VEGF-A) and an increased angiogenesis, which were reverted by treatment with E4031. On the whole, this article assigns a relevant role to hERG1 in the process of in vivo colorectal carcinogenesis.

Topics: Adenomatous Polyposis Coli; Animals; Azoxymethane; Carcinogenesis; Carcinogens; Colorectal Neoplasms; Disease Models, Animal; ERG1 Potassium Channel; Ether-A-Go-Go Potassium Channels; Gene Expression Regulation, Neoplastic; Humans; Intestinal Mucosa; Intestine, Large; Mice; Mice, Inbred C57BL; Mice, Transgenic; Neoplasm Proteins; Neovascularization, Pathologic; Piperidines; Proto-Oncogene Proteins c-akt; Pyridines; Vascular Endothelial Growth Factor A

Poor prognosis in patients with later stage colorectal cancer (CRC) necessitates the search for new treatment strategies. Ceramide, because of its role in orchestrating death cascades in cancer cells, is a versatile alternative. Ceramide can be generated by exposure to chemotherapy or ionizing radiation, or it can be administered in the form of short-chain analogs (C6-ceramide). Because intracellular P-glycoprotein (P-gp) plays a role in catalyzing the conversion of ceramide to higher sphingolipids, we hypothesized that administration of P-gp antagonists with C6-ceramide would magnify cell death cascades. Human CRC cell lines were employed, HCT-15, HT-29, and LoVo. The addition of either tamoxifen, VX-710, verapamil, or cyclosporin A, antagonists of P-gp, enhanced C6-ceramide cytotoxicity in all cell lines. In depth studies with C6-ceramide and tamoxifen in LoVo cells showed the regimen induced PARP cleavage, caspase-dependent apoptosis, mitochondrial membrane permeabilization (MMP), and cell cycle arrest at G1 and G2. At the molecular level, the regimen, but not single agents, induced time-dependent upregulation of tumor suppressor protein p53; however, introduction of a p53 inhibitor staved neither MMP nor apoptosis. Nanoliposomal formulations of C6-ceramide and tamoxifen were also effective, yielding synergistic cell kill. We conclude that tamoxifen is a favorable adjuvant for enhancing C6-ceramide cytotoxicity in CRC, and demonstrates uniquely integrated effects. The high frequency of expression of P-gp in CRC presents an adventitious target for complementing ceramide-based therapies, a strategy that could hold promise for treatment of resistant disease.

Topics: Antineoplastic Agents, Hormonal; Apoptosis; ATP Binding Cassette Transporter, Subfamily B, Member 1; Cell Cycle; Cell Line, Tumor; Ceramides; Colorectal Neoplasms; Drug Synergism; Humans; Piperidines; Pyridines; Tamoxifen; Tumor Suppressor Protein p53

[3,4-Difluoro-2-(2-fluoro-4-iodo-phenylamino)-phenyl]-((S)-3-hydroxy-3-piperidin-2-yl-azetidin-1-yl)-methanone (GDC-0973) is a potent and highly selective inhibitor of mitogen-activated protein kinase(MAPK)/extracellular signal-regulated kinase (ERK) 1/2 (MEK1/2), a MAPK kinase that activates ERK1/2. The objectives of these studies were to characterize the disposition of GDC-0973 in preclinical species and to determine the relationship of GDC-0973 plasma concentrations to efficacy in Colo205 mouse xenograft models. The clearance (CL) of GDC-0973 was moderate in mouse (33.5 ml · min(-1) · kg(-1)), rat (37.9 ± 7.2 ml · min(-1) · kg(-1)), and monkey (29.6 ± 8.5 ml · min(-1) · kg(-1)). CL in dog was low (5.5 ± 0.3 ml · min(-1) · kg(-1)). The volume of distribution across species was large, 6-fold to 15-fold body water; half-lives ranged from 4 to 13 h. Protein binding in mouse, rat, dog, monkey, and human was high, with percentage unbound, 1 to 6%. GDC-0973-related radioactivity was rapidly and extensively distributed to tissues; however, low concentrations were observed in the brain. In rats and dogs, [(14)C]GDC-0973 was well absorbed (fraction absorbed, 70-80%). The majority of [(14)C]GDC-0973-related radioactivity was recovered in the bile of rat (74-81%) and dog (65%). The CL and volume of distribution of GDC-0973 in human, predicted by allometry, was 2.9 ml · min(-1) · kg(-1) and 9.9 l/kg, respectively. The predicted half-life was 39 h. To characterize the relationship between plasma concentration of GDC-0973 and tumor growth inhibition, pharmacokinetic-pharmacodynamic modeling was applied using an indirect response model. The KC(50) value for tumor growth inhibition in Colo205 xenografts was estimated to be 0.389 μM, and the predicted clinical efficacious dose was ∼10 mg. Taken together, these data are useful in assessing the disposition of GDC-0973, and where available, comparisons with human data were made.

Topics: Administration, Oral; Animals; Antineoplastic Agents; Autoradiography; Azetidines; Bile; Brain; Cell Line, Tumor; Cell Membrane; Cell Membrane Permeability; Colorectal Neoplasms; Dogs; Dose-Response Relationship, Drug; Female; Humans; Injections, Intravenous; Macaca fascicularis; Male; Mice; Mice, Nude; Microsomes, Liver; Models, Biological; Piperidines; Predictive Value of Tests; Prospective Studies; Protein Kinase Inhibitors; Rats; Rats, Long-Evans; Rats, Sprague-Dawley; Retrospective Studies; Species Specificity; Tissue Distribution; Xenograft Model Antitumor Assays

The topoisomerase I inhibitor, irinotecan, and its active metabolite SN-38 have been shown to induce G(2) /M cell cycle arrest without significant cell death in human colon carcinoma cells (HCT-116). Subsequent treatment of these G(2) /M-arrested cells with the cyclin-dependent kinase inhibitor, flavopiridol, induced these cells to undergo apoptosis. The goal of this study was to develop a noninvasive metabolic biomarker for early tumor response and target inhibition of irinotecan followed by flavopiridol treatment in a longitudinal study. A total of eleven mice bearing HCT-116 xenografts were separated into two cohorts where one cohort was administered saline and the other treated with a sequential course of irinotecan followed by flavopiridol. Each mouse xenograft was longitudinally monitored with proton ((1) H)-decoupled phosphorus ((31) P) magnetic resonance spectroscopy (MRS) before and after treatment. A statistically significant decrease in phosphocholine (p = 0.0004) and inorganic phosphate (p = 0.0103) levels were observed in HCT-116 xenografts following treatment, which were evidenced within twenty-four hours of treatment completion. Also, a significant growth delay was found in treated xenografts. To discern the underlying mechanism for the treatment response of the xenografts, in vitro HCT-116 cell cultures were investigated with enzymatic assays, cell cycle analysis, and apoptotic assays. Flavopiridol had a direct effect on choline kinase as measured by a 67% reduction in the phosphorylation of choline to phosphocholine. Cells treated with SN-38 alone underwent 83 ± 5% G(2) /M cell cycle arrest compared to untreated cells. In cells, flavopiridol alone induced 5 ± 1% apoptosis while the sequential treatment (SN-38 then flavopiridol) resulted in 39 ± 10% apoptosis. In vivo (1) H-decoupled (31) P MRS indirectly measures choline kinase activity. The decrease in phosphocholine may be a potential indicator of early tumor response to the sequential treatment of irinotecan followed by flavopiridol in noninvasive and/or longitudinal studies.

Topics: Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Camptothecin; Cell Cycle; Choline Kinase; Choline-Phosphate Cytidylyltransferase; Colorectal Neoplasms; Female; Flavonoids; HCT116 Cells; Humans; Irinotecan; Magnetic Resonance Spectroscopy; Mice; Phosphorus Isotopes; Piperidines; Protons; Saccharomyces cerevisiae; Treatment Outcome; Xenograft Model Antitumor Assays

Colorectal carcinomas exhibit a frequent recurrence after curative surgery, which may partially be due to histopathologically inconspicuous minimal residual disease. Reliable markers for tumor cells in colorectal tissue are still missing. Therefore, in this study we compared the predictive value of the putative tumor markers carcinoembryonic antigen (CEA), cytokeratin-19 (CK19) and cytokeratin-20 (CK20) to that of a novel marker, the human ether-a-go-go-related gene (HERG1) K(+) channel, a suggested regulator of tumor cell proliferation.. Using RT-PCR we studied HERG, CEA, CK19 and CK20 expression in colorectal carcinomas and non-carcinoma controls. HERG1 immunhistochemistry was performed in a total of 66 specimens, in colorectal carcinoma (n = 23), in matched histopathologically negative samples (n = 23) taken near the excision site from the same tumor patients and in healthy control biopsies (n = 20). In order to verify the relevance of HERG1 for tumor proliferation we studied the effect of HERG1 inhibition in the Colo-205 colon cancer carcinoma cell line using the MTT-assay.. HERG1 was expressed in all tumor samples regardless of their stage and in adenomas larger than 0.4 cm, but absent in small adenomas, sigmadiverticulitis specimen and healthy histopathologically negative samples, except for one which developed a tumor recurrence. In contrast, CEA, CK19 and CK20 were absent in some tumors. The selective HERG1 inhibitor E-4031 dose-dependently impaired tumor growth in the proliferation assays.. Our data indicate that HERG1, but not CEA, CK19 or CK20, is a highly sensitive and reliable tumor biomarker that may constitute a novel molecular target for tumor treatment.

Topics: Adenocarcinoma; Aged; Aged, 80 and over; Biomarkers, Tumor; Carcinoembryonic Antigen; Cell Line, Tumor; Cell Proliferation; Colorectal Neoplasms; Dose-Response Relationship, Drug; Ether-A-Go-Go Potassium Channels; Female; Gene Expression; Humans; Immunohistochemistry; Keratin-19; Keratin-20; Male; Middle Aged; Piperidines; Polymerase Chain Reaction; Pyridines; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Sensitivity and Specificity; Tumor Cells, Cultured

Epidemiological and animal studies indicate that selenium supplementation suppresses risk of colorectal and other cancers. The majority of colorectal cancers are characterized by a defective DNA mismatch repair (MMR). Here, we have employed the MMR-deficient HCT 116 colorectal cancer cells and the MMR-proficient HCT 116 cells with hMLH1 complementation to investigate the role of hMLH1 in selenium-induced DNA damage response, a tumorigenesis barrier. The ATM (ataxia telangiectasia mutated) protein responds to clastogens and initiates DNA damage response. We show that hMLH1 complementation sensitizes HCT 116 cells to methylseleninic acid, methylselenocysteine, and sodium selenite via reactive oxygen species and facilitates the selenium-induced oxidative 8-oxoguanine damage, DNA breaks, G(2)/M checkpoint response, and ATM pathway activation. Pretreatment of the hMLH1-complemented HCT 116 cells with the antioxidant N-acetylcysteine or 2,2,6,6-tetramethylpiperidine-1-oxyl or the ATM kinase inhibitor KU55933 suppresses hMLH1-dependent DNA damage response to selenium exposure. Selenium treatment stimulates the association between hMLH1 and hPMS2 proteins, a heterodimer critical for functional MMR, in a manner dependent on ATM and reactive oxygen species. Taken together, the results suggest a new role of selenium in mitigating tumorigenesis by targeting the MMR pathway, whereby the lack of hMLH1 renders the HCT 116 colorectal cancer cells resistant to selenium-induced DNA damage response.

Topics: Acetylcysteine; Adaptor Proteins, Signal Transducing; Adenosine Triphosphatases; Anticarcinogenic Agents; Antioxidants; Ataxia Telangiectasia Mutated Proteins; Cell Cycle Proteins; Cell Line, Tumor; Colorectal Neoplasms; Cysteine; DNA Breaks; DNA Mismatch Repair; DNA Repair Enzymes; DNA-Binding Proteins; Drug Resistance, Neoplasm; Guanosine; Humans; Mismatch Repair Endonuclease PMS2; Morpholines; MutL Protein Homolog 1; Nuclear Proteins; Organoselenium Compounds; Piperidines; Protein Serine-Threonine Kinases; Pyrones; Reactive Oxygen Species; Selenocysteine; Sodium Selenite; Tumor Suppressor Proteins

The selective CB1 receptor antagonist rimonabant (SR141716) was shown to perform a number of biological effects in several pathological conditions. Emerging findings demonstrate that rimonabant exerts antitumor action in thyroid tumors and breast cancer cells. In our study, human colorectal cancer cells (DLD-1, CaCo-2 and SW620) were treated with rimonabant and analyzed for markers of cell proliferation, cell viability and cell cycle progression. Rimonabant significantly reduced cell growth and induced cell death. In addition, rimonabant was able to alter cell cycle distribution in all the cell lines tested. Particularly, rimonabant produced a G2/M cell cycle arrest in DLD-1 cells without inducing apoptosis or necrosis. The G2/M phase arrest was characterized by a parallel enhancement of the number of mitoses associated to elevated DNA double strand breaks and chromosome misjoining events, hallmarks of mitotic catastrophe. Protein expression analyses of Cyclin B1, PARP-1, Aurora B and phosphorylated p38/MAPK and Chk1 demonstrated that rimonabant-induced mitotic catastrophe is mediated by interfering with the spindle assembly checkpoint and the DNA damage checkpoint. Moreover, in the mouse model of azoxymethane-induced colon carcinogenesis, rimonabant significantly decreased aberrant crypt foci (ACF) formation, which precedes colorectal cancer. Our findings suggest that rimonabant is able to inhibit colorectal cancer cell growth at different stages of colon cancer pathogenesis inducing mitotic catastrophe in vitro.

Topics: Animals; Apoptosis; Aurora Kinase B; Aurora Kinases; Azoxymethane; Blotting, Western; Cannabinoid Receptor Antagonists; Cell Cycle; Cell Proliferation; Checkpoint Kinase 1; Chromosome Aberrations; Colony-Forming Units Assay; Colorectal Neoplasms; Cyclin B; Cyclin B1; DNA Damage; Female; Humans; Mice; Mice, Inbred C57BL; Mitotic Index; p38 Mitogen-Activated Protein Kinases; Phosphorylation; Piperidines; Poly (ADP-Ribose) Polymerase-1; Poly(ADP-ribose) Polymerases; Polyploidy; Precancerous Conditions; Protein Kinases; Protein Serine-Threonine Kinases; Pyrazoles; Rimonabant; Tumor Cells, Cultured

The tumor growth kinetics of the human LoVo colorectal xenograft model was assessed in response to vandetanib, an orally available receptor tyrosine kinase inhibitor, radiotherapy (RT), or irinotecan (CPT-11), as single therapies and in combination.. LoVo cells were injected subcutaneously into the right hind limb (5 x 10(6) cells in 100 microL phosphate-buffered saline) of athymic NCR NUM mice and tumors were grown to a volume of 200-300 mm(3) before treatment. Vandetanib was administered at 50 mg/kg daily orally for 14 days starting on Day 1. RT was given as three fractions (3 x 3 Gy) on Days 1, 2, and 3. CPT-11 was given at 15 mg/kg intraperitoneally on Days 1 and 3. Tumor volumes were measured on a daily basis and calculated by measuring tumor diameters with digital calipers in two orthogonal dimensions.. All three single treatments (vandetanib, CPT-11, and radiation) significantly slowed LoVo colorectal tumor growth. Vandetanib significantly increased the antitumor effects of CPT-11 and radiation when given in combination with either of these treatments. These treatment combinations resulted in a slow tumor growth rate during the 2 weeks of vandetanib administration. The triple combination of vandetanib, CPT-11, and radiation produced the most marked improvement in response as observed by measurable shrinkage of tumors during the first week of treatment.. The tumor growth delay kinetics observed in this study of the LoVo colorectal model suggest concurrent and sustained post-sequencing of vandetanib with cytotoxic therapy may be beneficial in tumors of this type.

Topics: Angiogenesis Inhibitors; Animals; Antineoplastic Agents, Phytogenic; Camptothecin; Colorectal Neoplasms; Combined Modality Therapy; Dose Fractionation, Radiation; ErbB Receptors; Humans; Irinotecan; Mice; Mice, Nude; Piperidines; Protein Kinase Inhibitors; Quinazolines; Tumor Burden; Xenograft Model Antitumor Assays

Evidence is accumulating that compounds of plant origin (phytochemicals) exert anti-cancer effects. The purpose of this study was to determine if resveratrol, cinnamaldehyde, and piperine (from red grapes, cinnamon, black pepper respectively) have anti-proliferative effects on colon cancer.. Quantitative effects of each phytochemical on concentration responses and time courses of proliferation of cultured human colon cancer cells (DLD-1) were assessed.. Research was performed at Saint Louis University.. Responses were measured by spectrophotometry of surviving cells stained by a dye method.. Phytochemicals displayed anti-proliferative effects on DLD-1 cells in concentration- and kinetic-dependent manners. Cinnamaldehyde offered statistically significant effects at 24 hours [200 microM], 48 hours [100 - 200 microM], and 72 hours [200 microM]. Piperine displayed a trend towards anti-proliferation at 24 hours and statistically significant inhibition at 48 and 72 hours [100 - 200 microM]. Resveratrol displayed significant anti-proliferative effects at 24 hours [50-200 microM], 48 hours [10-200 microM], and 72 hours [10-200 microM].. Cinnamaldehyde, piperine, and resveratrol offer significant in vitro anti-proliferative effects on cultured human colon cancer cells. While each phytochemical exhibited significant anti-proliferative effects, resveratrol results were most impressive in that lower concentrations administered at regular intervals were significantly effective. These results taken together with everyday dietary availability of concentrations used in this study strongly suggest that regular intake of low doses of these phytochemicals offer preventive effects against colon cancer.

Topics: Acrolein; Adenocarcinoma; Antineoplastic Agents, Phytogenic; Cell Line, Tumor; Cell Proliferation; Colorectal Neoplasms; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Humans; Piperidines; Plant Extracts; Resveratrol; Stilbenes

Topics: Adenoma; Anti-Obesity Agents; Apoptosis; Carcinoma; Cell Transformation, Neoplastic; Colorectal Neoplasms; Dronabinol; Drug Inverse Agonism; Humans; Inflammatory Bowel Diseases; Intestinal Mucosa; Obesity; Piperidines; Pyrazoles; Receptor, Cannabinoid, CB1; Receptor, Cannabinoid, CB2; Rimonabant

Topics: Animals; Anti-Inflammatory Agents; Anti-Obesity Agents; Antineoplastic Agents; Carcinoma; Cell Survival; Colorectal Neoplasms; Dose-Response Relationship, Drug; Humans; Mice; Obesity; Piperidines; Pyrazoles; Receptor, Cannabinoid, CB1; Rimonabant; Time Factors

Topics: Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Axitinib; Bevacizumab; Biomedical Research; Breast Neoplasms; Cetuximab; Clinical Trials as Topic; Colorectal Neoplasms; Deoxycytidine; Female; Gemcitabine; Humans; Imidazoles; Indazoles; Male; Molecular Structure; Neoplasms; Organoplatinum Compounds; Pancreatic Neoplasms; Piperidines; Prednisolone; Prostatic Neoplasms; Quinazolines; Treatment Outcome

In this study, the efficacy of combining ZD6474 (Zactima), a vascular endothelial growth factor (VEGF) receptor 2-associated tyrosine kinase inhibitor currently undergoing Phase II clinical trial evaluation, with single and fractionated dose radiation exposures was examined in a human colorectal carcinoma model (HT29).. HT29 xenograft-bearing mice were treated with either single-dose (10 Gy) or multifraction (2 Gy/day for 2 weeks) radiotherapy alone or in conjunction with a 2-week course of ZD6474 (25 mg/kg). In the single-dose investigation, ZD6474 treatment followed radiotherapy, whereas in the fractionated dose studies the antiangiogenic therapy was given before, after, or concurrent with the radiation. Tumor response was determined by tumor growth delay.. ZD6474 increased the response of HT29 xenografts to both single and fractionated dose radiotherapy. In the fractionation studies sequencing of therapies had little impact on treatment outcomes; the time for the median tumors in each of the treatment groups to grow to five times the starting size was 53, 53.5, and 49 days, respectively.. These studies indicate that ZD6474, when used in conjunction with radiation therapy, has a clear therapeutic advantage, providing a rationale for considering the combination of this agent with radiotherapy in the clinic.

Topics: Angiogenesis Inhibitors; Animals; Colorectal Neoplasms; Combined Modality Therapy; Enzyme Inhibitors; Female; HT29 Cells; Humans; Mice; Mice, Inbred Strains; Mice, Nude; Piperidines; Protein-Tyrosine Kinases; Quinazolines; Radiotherapy Dosage; Vascular Endothelial Growth Factor Receptor-2

Tumor hypoxia modifies the efficacy of conventional anticancer therapy and promotes malignant tumor progression. Human chorionic gonadotropin (hCG) is a glycoprotein secreted during pregnancy that has been used to monitor tumor burden in xenografts engineered to express this marker. We adapted this approach to use urinary beta-hCG as a secreted reporter protein for tumor hypoxia. We used a hypoxia-inducible promoter containing five tandem repeats of the hypoxia-response element (HRE) ligated upstream of the beta-hCG gene. This construct was stably integrated into two different cancer cell lines, FaDu, a human head and neck squamous cell carcinoma, and RKO, a human colorectal cancer cell line. In vitro studies showed that tumor cells stably transfected with this plasmid construct secrete beta-hCG in response to hypoxia or hypoxia-inducible factor 1alpha (HIF-1alpha) stabilizing agents. The hypoxia responsiveness of this construct can be blocked by treatment with agents that affect the HIF-1alpha pathways, including topotecan, 1-benzyl-3-(5'-hydroxymethyl-2'-furyl)indazole (YC-1), and flavopiridol. Immunofluorescent analysis of tumor sections and quantitative assessment with flow cytometry indicate colocalization between beta-hCG and 2-(2-nitro-1H-imidazol-1-yl)-N-(2,2,3,3,3-pentafluoropropyl)acetamide (EF5) and beta-hCG and pimonidazole, two extrinsic markers for tumor hypoxia. Secretion of beta-hCG from xenografts that contain these stable constructs is directly responsive to changes in tumor oxygenation, including exposure of the animals to 10% O2 and tumor bed irradiation. Similarly, urinary beta-hCG levels decline after treatment with flavopiridol, an inhibitor of HIF-1 transactivation. This effect was observed only in tumor cells expressing a HRE-regulated reporter gene and not in tumor cells expressing a cytomegalovirus-regulated reporter gene. The 5HRE beta-hCG reporter system described here enables serial, noninvasive monitoring of tumor hypoxia in a mouse model by measuring a urinary reporter protein.

Topics: Animals; Carcinoma, Squamous Cell; Cell Hypoxia; Cell Line, Tumor; Chorionic Gonadotropin, beta Subunit, Human; Colorectal Neoplasms; DNA-Binding Proteins; Flavonoids; Genes, Reporter; Genetic Vectors; Head and Neck Neoplasms; Humans; Hypoxia-Inducible Factor 1; Hypoxia-Inducible Factor 1, alpha Subunit; Mice; Mice, Inbred BALB C; Mice, Inbred SENCAR; Neoplasm Transplantation; Nuclear Proteins; Piperidines; Topotecan; Transcription Factors; Transfection; Transplantation, Heterologous

Flavopiridol is a broad-spectrum inhibitor of cyclin-dependent kinases (cdks) and represents the first in this anticancer class to enter clinical trials. In anticipation of the likelihood that, as with other cancer drugs, acquired resistance may limit the drug's efficacy, an acquired resistance model has been established by in vitro drug exposure of the human colon carcinoma cell line HCT116. This stably resistant line, possessing 8-fold resistance to flavopiridol, showed a lack of cross-resistance to the anticancer agents etoposide, doxorubicin, paclitaxel, topotecan, and cisplatin, and notably to other chemical classes of cdk inhibitors: the aminopurines roscovitine and purvalanol A, 9-nitropaullone, and hymenialdisine. Resistance did not seem to be related to differences in the levels of multidrug resistance drug efflux proteins, P-glycoprotein, and MRP1. Moreover, there were no changes in overall drug accumulation between the resistant and sensitive cell lines. Flavopiridol induced cell cycle arrest, apoptosis, and inhibition of retinoblastoma gene product phosphorylation on serine 780 in both parental and resistant lines, but the latter required 8-fold higher concentrations to achieve these effects. Cyclin E protein levels and cyclin E-associated kinase activity were increased in the resistant line, suggesting that overexpression of cyclin E may be the mechanism of resistance to flavopiridol. However, transfection of cyclin E to increase expression of this protein did not result in an increase in resistance to flavopiridol. Thus, up-regulation of cyclin E alone does not seem to cause resistance to this cdk inhibitor.

Topics: Antineoplastic Agents; Apoptosis; Biological Transport; Cell Cycle; Cell Cycle Proteins; Cell Division; Colorectal Neoplasms; Cyclin E; Drug Resistance, Neoplasm; Flavonoids; Humans; Phosphorylation; Phosphotransferases; Piperidines; Retinoblastoma Protein; Transfection; Tumor Cells, Cultured

The underlying pathophysiology of idiopathic slow transit constipation (ISTC) remains unclear. At present, there is little evidence to implicate a smooth muscle myopathy in the aetiology of this condition. This study compared the effect of cisapride on the cholinergic response of colonic muscle strips from patients with this condition with that of control tissue.. Isometric tension production was recorded from circular smooth muscle strips taken from five patients undergoing colectomy for ISTC in response to cumulative concentrations of carbachol (100 nmol/1-100 mumol/l) alone and in the presence of cisapride 400 nmol/l. Similar dose-response activity was obtained for a control group consisting of six patients undergoing resection for colorectal carcinoma.. In the absence of cisapride, smooth muscle from patients with carcinoma exhibited a significantly lower sensitivity to cholinergic stimulation (agonist concentration required to produce half-maximal activation (EC50) 4.83 mumol/l) than that from patients with ISTC (EC50 1.63 mumol/l, P = 0.036), and also a greater maximal frequency of the oscillatory activity associated with the increase in isometric tension (0.070 versus 0.049 Hz, P = 0.035). Cisapride had no effect on the sensitivity to carbachol of the carcinoma tissue but brought about a significant reduction in the sensitivity of smooth muscle from patients with ISTC (EC50 3.24 mumol/l, P = 0.043).. These findings indicate that colonic smooth muscle from patients with ISTC is hypersensitive to cholinergic stimulation and suggest the existence of a smooth muscle myopathy in this condition.

Topics: Adolescent; Adult; Aged; Carbachol; Cisapride; Colorectal Neoplasms; Constipation; Female; Gastrointestinal Transit; Humans; Isometric Contraction; Middle Aged; Muscle, Smooth; Piperidines

Bioreducible anti-tumour agents are prodrugs which are intended to be inactive in normal cells, but are able to undergo metabolic reduction in cancer cells to produce toxic species that can damage biomolecules. A series of N-oxides of heterocyclic aliphatic amines were designed and prepared as mentioned below as bioreducible drugs based on the reported anti-cancer activity of 2,6-bis(halomethyl)piperidines. In order to study structure-activity relationships in these conformationally restricted nitrogen mustards, samples of cis- and trans-2,6-dihydroxymethyl-N-methylpiperidine were prepared and converted into a number of carbamate or halogen derivatives. The free bases were designed to be bifunctional alkylating agents via aziridinium ion formation. The corresponding N-oxides were also prepared for comparison in cytotoxicity tests. In total, 21 new compounds were synthesized plus cis-N-methyl-2,6-bis(chloromethyl)-piperidine (prepared previously but lacking spectroscopic data) and tested against two human colon carcinoma cell lines, HT 29 (high DT-diaphorase) and BE (no DT-diaphorase), under oxic and hypoxic conditions. The majority of the free bases were equally toxic against both cell lines. The most toxic compounds were cis- and trans-N-methyl-2,6-bis(bromomethyl)piperidine with oxic IC50 values between 6 and 11 microM against both cell lines. The N-oxides were relatively non-toxic under both oxic and hypoxic conditions apart from the N-oxide of trans-N-methyl-2,6-bis(bromomethyl)-piperidine. Their low toxicity suggested that the N-oxides are not reduced under hypoxic conditions. We conclude that: (i) 2,6-disubstituted N-methylpiperidine derivatives are chemically versatile cytotoxic entities that are suitable for prodrugging to enhance their therapeutic selectivity; and (ii) N-oxide prodrugs of these compounds are deactivated chemically and display reduced cytotoxicity compared to the parent amines but are apparently not reduced under hypoxic conditions. At least in the colorectal cell lines tested the latter issue would need to be addressed by modifying the redox properties in future work to progress this approach.

Topics: Antineoplastic Agents, Alkylating; Biotransformation; Carcinoma; Cell Hypoxia; Colorectal Neoplasms; Dihydrolipoamide Dehydrogenase; Humans; Neoplasm Proteins; Nitrogen; Oxidation-Reduction; Oxides; Piperidines; Prodrugs; Structure-Activity Relationship; Tumor Cells, Cultured

Four new antagonists of platelet activating factor (PAF) from two different chemical classes (imidazoisoquinolines: SDZ 62-434, SDZ 63-135, SDZ 62-759; imidazopiperidines: SDZ 62-293) were tested for in vivo therapeutic activity in various tumor models including the murine myelomonocytic leukemia WEHl-3B, xenografts of human colon (HTB 38) and lung (HTB 119) cancer cell lines and the murine Lewis-lung tumor. After intraperitoneal (i.p.) injection of 1 x 10(3), 5 x 10(3) and 1 x 10(4) WEHl-3B cells into Balb/c mice, the drugs were given per os (p.o.) or i.p. over 6-14 days. Drug doses were pushed to exceed the lethal dose for 10% of the animals (LD10) and ranged from 1 to 100 mg/kg daily for p.o. treatment and from 1 to 75 mg/kg daily for i.p. treatment. In the xenotransplants and the Lewis-lung tumor experiments, PAF antagonists were given i.p. to nude Balb/c and C57 Black mice after intracutaneous (i.c.) tumor cell inoculation. None of the four compounds induced reproducible prolongation of life span, significant numbers of long term survivors, reduction of tumor size, or delay of tumor growth in any of the therapeutic models. Oral SDZ 62-759 had some activity in experiments in which there was slow WEHl-38 tumor growth in the controls. Toxicity of equivalent drugs doses was higher in the i.p. than in the p.o. schedules.

Topics: Animals; Antineoplastic Agents; Colorectal Neoplasms; Drug Screening Assays, Antitumor; Female; Humans; Imidazoles; Isoquinolines; Leukemia, Experimental; Lung Neoplasms; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Nude; Neoplasm Transplantation; Piperidines; Platelet Activating Factor