pyrimidinones and Pancreatic-Neoplasms

There is paucity of investigations into immunotherapy or targeted therapy for postoperative locally recurrent pancreatic cancer. We aimed to assess the efficacy of stereotactic body radiotherapy (SBRT) plus pembrolizumab and trametinib in these patients.. In this open-label, randomised, controlled, phase 2 study, participants were recruited from Changhai Hospital affiliated to the Naval Medical University, Shanghai, China. Eligible patients were aged 18 years or older with histologically confirmed pancreatic ductal adenocarcinoma characterised by mutant KRAS and positive immunohistochemical staining of PD-L1, Eastern Cooperative Oncology Group performance status of 0 or 1, and documented local recurrence after surgery followed by chemotherapy (mFOLFIRINOX [ie, 5-fluorouracil, oxaliplatin, irinotecan, and folinic acid] or 5-fluorouracil). Eligible participants were randomly assigned (1:1) using an interactive voice or web response system, without stratification, to receive SBRT with doses ranging from 35-40 Gy in five fractions, intravenous pembrolizumab 200 mg once every 3 weeks, and oral trametinib 2 mg once daily or SBRT (same regimen) and intravenous gemcitabine (1000 mg/m. Between Oct 10, 2016, and Oct 28, 2017, 198 patients were screened, of whom 170 patients were enrolled and randomly assigned to receive SBRT plus pembrolizumab and trametinib (n=85) or SBRT plus gemcitabine (n=85). As of the clinical cutoff date (Nov 30, 2020), median follow-up was 13·1 months (IQR 10·2-17·1). Median overall survival was 14·9 months (12·7-17·1) with SBRT plus pembrolizumab and trametinib and 12·8 months (95% CI 11·2-14·4) with SBRT plus gemcitabine (hazard ratio [HR] 0·69 [95% CI 0·51-0·95]; p=0·021). The most common grade 3 or 4 adverse effects were increased alanine aminotransferase or aspartate aminotransferase (ten [12%] of 85 in SBRT plus pembrolizumab and trametinib group vs six [7%] of 85 in SBRT plus gemcitabine group), increased blood bilirubin (four [5%] vs none), neutropenia (one [1%] vs nine [11%]), and thrombocytopenia (one [1%] vs four [5%]). Serious adverse events were reported by 19 (22%) participants in the SBRT plus pembrolizumab and trametinib group and 12 (14%) in the SBRT plus gemcitabine group. No treatment-related deaths occurred.. The combination of SBRT plus pembrolizumab and trametinib could be a novel treatment option for patients with locally recurrent pancreatic cancer after surgery. Phase 3 trials are needed to confirm our findings.. Shanghai Shenkang Center and Changhai Hospital.. For the Chinese translation of the abstract see Supplementary Materials section.

Topics: Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; China; Deoxycytidine; Fluorouracil; Gemcitabine; Humans; Neoplasm Recurrence, Local; Pancreatic Neoplasms; Pyridones; Pyrimidinones; Radiosurgery

There is paucity of investigations into immunotherapy or targeted therapy for postoperative locally recurrent pancreatic cancer. We aimed to assess the efficacy of stereotactic body radiotherapy (SBRT) plus pembrolizumab and trametinib in these patients.. In this open-label, randomised, controlled, phase 2 study, participants were recruited from Changhai Hospital affiliated to Naval Medical University, Shanghai, China. Eligible patients were aged 18 years or older with histologically confirmed pancreatic ductal adenocarcinoma characterised by mutant KRAS and positive immunohistochemical staining of PD-L1, Eastern Cooperative Oncology Group performance status of 0 or 1, and documented local recurrence after surgery followed by chemotherapy (mFOLFIRINOX or 5-fluorouracil). Eligible participants were randomly assigned (1:1) using an interactive voice or web response system, without stratification, to receive SBRT with doses ranging from 35-40 Gy in five fractions, intravenous pembrolizumab 200 mg once every 3 weeks, and oral trametinib 2 mg once daily or SBRT (same regimen) and intravenous gemcitabine (1000 mg/m. Between Oct 10, 2016, and Oct 28, 2017, 198 patients were screen, of whom 170 patients were enrolled and randomly assigned to receive SBRT plus pembrolizumab and trametinib (n=85) or SBRT plus gemcitabine (n=85). As of the clinical cutoff date (Nov 30, 2020), median follow-up was 23·3 months (IQR 20·5-27·4). Median overall survival was 24·9 months (23·3-26·5) with SBRT plus pembrolizumab and trametinib and 22·4 months (95% CI 21·2-23·6) with SBRT plus gemcitabine (hazard ratio [HR] 0·60 [95% CI 0·44-0·82]; p=0·0012). The most common grade 3 or 4 adverse effects were increased alanine aminotransferase or aspartate aminotransferase (ten [12%] of 85 in SBRT plus pembrolizumab and trametinib group vs six [7%] of 85 in SBRT plus gemcitabine group), increased blood bilirubin (four [5%] vs none), neutropenia (one [1%] vs nine [11%]), and thrombocytopenia (one [1%] vs four [5%]). Serious adverse events were reported by 19 (22%) participants in the SBRT plus pembrolizumab and trametinib group and 12 (14%) in the SBRT plus gemcitabine group. No treatment-related deaths occurred.. The combination of SBRT plus pembrolizumab and trametinib could be a novel treatment option for patients with locally recurrent pancreatic cancer after surgery. Phase 3 trials are needed to confirm our findings.. Shanghai Shenkang Center and Changhai Hospital.. For the Chinese translation of the abstract see Supplementary Materials section.

Topics: Aged; Antibodies, Monoclonal, Humanized; Carcinoma, Pancreatic Ductal; China; Combined Modality Therapy; Deoxycytidine; Female; Gemcitabine; Humans; Male; Middle Aged; Pancreatic Neoplasms; Pyridones; Pyrimidinones; Radiosurgery

KRAS oncogene mutations cause sustained signaling through the MAPK pathway. Concurrent inhibition of MEK, EGFR, and HER2 resulted in complete inhibition of tumor growth in KRAS-mutant (KRASm) and PIK3CA wild-type tumors, in vitro and in vivo. In this phase I study, patients with advanced KRASm and PIK3CA wild-type colorectal cancer (CRC), non-small cell lung cancer (NSCLC), and pancreatic cancer, were treated with combined lapatinib and trametinib to assess the recommended phase 2 regimen (RP2R).. Patients received escalating doses of continuous or intermittent once daily (QD) orally administered lapatinib and trametinib, starting at 750 mg and 1 mg continuously, respectively.. Thirty-four patients (16 CRC, 15 NSCLC, three pancreatic cancers) were enrolled across six dose levels and eight patients experienced dose-limiting toxicities, including grade 3 diarrhea (n = 2), rash (n = 2), nausea (n = 1), multiple grade 2 toxicities (n = 1), and aspartate aminotransferase elevation (n = 1), resulting in the inability to receive 75% of planned doses (n = 2) or treatment delay (n = 2). The RP2R with continuous dosing was 750 mg lapatinib QD plus 1 mg trametinib QD and with intermittent dosing 750 mg lapatinib QD and trametinib 1.5 mg QD 5 days on/2 days off. Regression of target lesions was seen in 6 of the 24 patients evaluable for response, with one confirmed partial response in NSCLC. Pharmacokinetic results were as expected.. Lapatinib and trametinib could be combined in an intermittent dosing schedule in patients with manageable toxicity. Preliminary signs of anti-tumor activity in NSCLC have been observed and pharmacodynamic target engagement was demonstrated.

Topics: Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Non-Small-Cell Lung; Colorectal Neoplasms; Dose-Response Relationship, Drug; Drug Monitoring; Female; Humans; Lapatinib; Male; Middle Aged; Mutation; Pancreatic Neoplasms; Pharmacogenetics; Proto-Oncogene Proteins p21(ras); Pyridones; Pyrimidinones; Treatment Outcome

AZD1775 (adavosertib) is an inhibitor of the Wee1 kinase. In this study, we built on our preclinical studies to evaluate the safety and efficacy of AZD1775 in combination with gemcitabine and radiation in patients with newly diagnosed locally advanced pancreatic cancer.. Thirty-four patients with locally advanced pancreatic cancer were enrolled with the intention to receive four 21-day cycles of gemcitabine (1,000 mg/m. The recommended phase II dose of AZD1775 was 150 mg/d. Eight patients (24%) experienced a dose-limiting toxicity, most commonly anorexia, nausea, or fatigue. The median overall survival for all patients was 21.7 months (90% CI, 16.7 to 24.8 months), and the median progression-free survival was 9.4 months (90% CI, 8.0 to 9.9 months). Hair follicle biopsy samples demonstrated evidence of Wee1 inhibition with decreased phosphorylation of cyclin-dependent kinase 1 staining by immunohistochemistry after AZD1775 administration at the recommended phase II dose.. AZD1775 in combination with gemcitabine and radiation therapy was well tolerated at a dose that produced target engagement in a surrogate tissue. The overall survival is substantially higher than prior results combining gemcitabine with radiation therapy and warrants additional investigation.

Topics: Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Cell Cycle Proteins; Chemoradiotherapy; Deoxycytidine; Dose-Response Relationship, Drug; Enzyme Inhibitors; Female; Gemcitabine; Humans; Male; Middle Aged; Pancreatic Neoplasms; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidinones; Survival Rate

Topics: Adenocarcinoma; Chemoradiotherapy; Combined Modality Therapy; Dose-Response Relationship, Drug; Humans; Pancreatic Neoplasms; Progression-Free Survival; Pyrazoles; Pyrimidinones

Trametinib is an inhibitor of MEK1/MEK2 activation and kinase activity. In order to evaluate the safety, tolerability, pharmacokinetics, and preliminary efficacy of single-agent trametinib (part 1) and trametinib in combination with gemcitabine (part 2), we undertook the first clinical study of this combination in Japanese patients with cancer and herein report our results.. In part 1, 13 patients with advanced solid tumors were enrolled into 3 dose cohorts, receiving trametinib once daily at a dose of 1.0, 2.0, or 3.0 mg. In part 2, 5 patients with pancreatic cancer received trametinib (2.0 mg once daily) in combination with gemcitabine (1000 mg/m(2)).. In part 1, a dose-limiting toxicity was observed in a patient in the 2.0-mg dose cohort, but the maximum tolerated dose was not reached at doses up to 3.0 mg daily. The best overall response was a PR in 1 patient, and 6 patients had SD. In part 2, the combination of trametinib and gemcitabine was tolerated for a short period of time. However, serious interstitial lung disease (ILD) was observed in 3 of 5 patients 4 weeks or more after the start of the treatment, including 1 fatal case. Three patients achieved a PR, and 2 patients had SD. The most common adverse event was rash (85 % in part 1 and 100 % in part 2).. Trametinib monotherapy was tolerable in Japanese patients with cancer. However, the combination of trametinib plus gemcitabine carried a higher risk as compared with monotherapy, during which no ILD was observed. (ClinicalTrials.gov number, NCT01324258.).

Topics: Adult; Aged; Antineoplastic Agents; Area Under Curve; Asian People; Deoxycytidine; Dose-Response Relationship, Drug; Drug Therapy, Combination; Female; Gemcitabine; Humans; Japan; Male; Maximum Tolerated Dose; Middle Aged; Neoplasms; Pancreatic Neoplasms; Pyridones; Pyrimidinones

Trametinib, an oral mitogen/extracellular signal-related kinase (MEK)1/2 inhibitor, holds promise for malignancies with rat sarcoma (RAS) mutations, like pancreas cancer. This phase II study was designed to determine overall survival (OS) in patients with pancreas cancer treated with trametinib and gemcitabine. Secondary end-points included progression-free survival (PFS), overall response rate (ORR) and duration of response (DOR); safety end-points were also assessed.. Adults with untreated metastatic adenocarcinoma of the pancreas were randomised (1:1) to receive intravenous gemcitabine 1000 mg/m(2) (weekly × 7 for 8 weeks, then days 1, 8 and 15 of 28-day cycles) plus trametinib or placebo 2mg daily. RAS mutations were determined in circulating free DNA (cfDNA) and archival tumour tissue. OS was evaluated in kirsten rat sarcoma viral oncogene homolog (KRAS) mutant and wild-type subgroups.. Baseline characteristics for 160 patients were similar in both treatment arms. There was no significant difference in OS (hazard ratio (HR) 0.98; 95% confidence interval (CI), 0.67-1.44; P=.453); median OS was 8.4 months with gemcitabine plus trametinib and 6.7 months with gemcitabine plus placebo. Median PFS (16 versus 15 weeks), ORR (22% versus 18%) and median DOR (23.9 versus 16.1 weeks) were also similar for trametinib and placebo arms, respectively. KRAS mutation-positive patients (n=103) showed no difference in OS between arms. Thrombocytopenia, diarrhoea, rash and stomatitis were more frequent with trametinib, as was grade 3 anaemia.. The addition of trametinib to gemcitabine did not improve OS, PFS, ORR or DOR in patients with previously untreated metastatic pancreas cancer. Outcomes were independent of KRAS mutations determined by cfDNA.

Topics: Adenocarcinoma; Administration, Oral; Adult; Aged; Aged, 80 and over; Antimetabolites, Antineoplastic; Antineoplastic Combined Chemotherapy Protocols; Deoxycytidine; Double-Blind Method; Female; Gemcitabine; Humans; Male; Middle Aged; Pancreatic Neoplasms; Protein Kinase Inhibitors; Pyridones; Pyrimidinones; Survival Analysis

Topics: Antibodies, Monoclonal, Humanized; Humans; Pancreatic Neoplasms; Pyridones; Pyrimidinones; Radiosurgery

Topics: Antibodies, Monoclonal, Humanized; Humans; Pancreatic Neoplasms; Pyridones; Pyrimidinones; Radiosurgery

Topics: Animals; Antineoplastic Agents; Apoptosis; beta Catenin; Biomarkers, Tumor; Carcinoma, Pancreatic Ductal; Cell Proliferation; Gene Expression Regulation, Neoplastic; Heterocyclic Compounds, 4 or More Rings; Humans; Mice; Mice, Inbred NOD; Mice, SCID; Mitogen-Activated Protein Kinases; Pancreatic Neoplasms; Pyridones; Pyrimidinones; Tumor Cells, Cultured; Wnt1 Protein; Xenograft Model Antitumor Assays

Over the last decades, cytotoxic chemotherapy has been the cornerstone of metastatic pancreatic adenocarcinoma treatment. In late-stage disease, a range of treatment regimens still offers minor benefits. Molecular profiling studies have shown that pancreatic adenocarcinoma (PDAC) is a mutation-driven tumor type, with KRAS mutations found in approximately 90% of cases, which could partially explain the resistance to chemotherapy. Preclinical data on selective targeting of a downstream point of the RAF-MEK-ERK pathway with a MEK inhibitor along with the concurrent use of an autophagy inhibitor such as hydroxychloroquine appears to be one alternative approach to overcome resistance and inhibit cell proliferation.. We herein aim to investigate the rationale of autophagy inhibitors use and describe the outcomes of patients who received this experimental treatment.. Two patients have received this experimental regimen from January 2020 to the present date, achieving disease stabilization that is clinically meaningful, considering the chemoresistance scenario of the included patients.. Our real-life data regarding KRAS-mutated PDAC patients who received treatment with the MEK inhibitor trametinib combined with hydroxychloroquine after experiencing disease progression are consistent with the preclinical data, pointing to the clinical benefits of this regimen.

Topics: Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Autophagy; CA-19-9 Antigen; Carcinoma, Pancreatic Ductal; Disease Progression; Dose-Response Relationship, Drug; Drug Resistance, Neoplasm; Female; Humans; Hydroxychloroquine; Male; MAP Kinase Signaling System; Middle Aged; Mutation; Neoplasm Staging; Pancreas; Pancreatic Neoplasms; Positron Emission Tomography Computed Tomography; Proto-Oncogene Proteins p21(ras); Pyridones; Pyrimidinones; Treatment Outcome

Autophagy and cell-cycle checkpoints act in concert to confer cellular radioresistance. We investigated the functional interaction between radiation-induced autophagy and G2 checkpoint activation in highly radioresistant human pancreatic ductal adenocarcinoma (PDAC) cells.. Four human PDAC cell lines (MIA PaCa-2, KP-4, Panc-1, and SUIT-2) were analyzed. These cells were first irradiated using x-rays, and their cell cycle status, autophagy, and cell cycle checkpoint marker expression and ATP production levels were evaluated. Autophagic flux assays and siRNA knockdown were used to evaluate autophagy activity. Double thymidine block experiments were performed to synchronize the cells. Two inhibitors (MK-1775 and SCH 900776) were used to attenuate G2 checkpoint activation. Cell survival assays and animal experiments were performed to evaluate the radiosensitizing effects of the G2 checkpoint inhibitors.. Autophagy and G2/M accumulation were synchronously induced in human PDAC cells with an activated G2 checkpoint at 12 hours after x-ray irradiation of 6 Gy. Radiation-induced autophagy produced the ATP levels required for cell survival. Double thymidine block experiments revealed that no autophagy occurred in cells that were solely in G2 phase. MK-1775 or SCH 900776 exposure attenuated not only G2 checkpoint activation but also postirradiation autophagy, indicating the dependence of radiation-induced autophagy on an activated G2 checkpoint. The inhibitors demonstrated a higher radiosensitizing effect in the PDAC cells than the autophagy inhibitor chloroquine. MK-1775 in combination with x-rays significantly suppressed the tumor growth of MIA PaCa-2 xenografts compared with other treatment groups, including radiation or drug exposure alone, to enhance the radiosensitivity of PDAC cells in vivo.. Biological crosstalk exists between the G2 checkpoint activation and radiation-induced autophagy processes that are believed to independently contribute to the radioresistance of human PDAC cells. These findings have important implications for the development of future radiation therapy strategies for PDAC.

Topics: Adenosine Triphosphate; Animals; Autophagy; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Female; G2 Phase Cell Cycle Checkpoints; Humans; Mice; Mice, Inbred BALB C; Pancreatic Neoplasms; Pyrazoles; Pyrimidinones; Quinolines; Radiation Tolerance; Thiazoles

Topics: Aged; Antineoplastic Combined Chemotherapy Protocols; Asymptomatic Diseases; Biopsy, Fine-Needle; Female; Humans; Imidazoles; Liver Neoplasms; Melanoma; Mitogen-Activated Protein Kinase Kinases; Oximes; Pancreas; Pancreatic Neoplasms; Protein Kinase Inhibitors; Proto-Oncogene Proteins B-raf; Pyridones; Pyrimidinones; Tomography, X-Ray Computed; Treatment Outcome; Ultrasonography

Pancreatic cancer is a lethal solid malignancy with limited therapeutic options. The development of novel therapeutic drugs requires adequate new cell line models. A new pancreatic cancer cell line, designated PDXPC1, was established from one pancreatic ductal adenocarcinoma (PDAC) patient‑derived xenograft. The PDXPC1 cells were stably cultured for >2 years and had a stable short tandem repeat profile. The PDXPC1 cell line retained the key mutations of the primary tumor, along with the epithelial origin and other important protein expression. The PDXPC1 cells induced rapid in vivo tumor growth, both subcutaneously and orthotopically, in a mouse model with an elevated CA199 level. The PDXPC1 cells showed weak growth, invasion and migration potency compared to another pancreatic cancer cell line, but were relatively resistant to multiple anti‑cancer drugs. Interestingly, the MEK inhibitor trametinib significantly inhibited the proliferation of PDXPC1 cells, and not that of Panc‑1 cells, by inactivating MEK/ERK/MYC signaling and activating the apoptotic pathway via Bcl‑2 degradation. In conclusion, the PDXPC1 cell line, capturing the major characteristics of the primary tumor, may be a suitable tool for studying the underlying mechanisms of chemo‑resistance in PDAC and developing new targeted therapeutic options.

Topics: Animals; Carcinoma, Pancreatic Ductal; Cell Culture Techniques; Cell Proliferation; Cell Survival; Female; Humans; Mice; Mutation; Pancreatic Neoplasms; Protein Kinase Inhibitors; Pyridones; Pyrimidinones; Signal Transduction; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Molecular mechanisms underlying adaptive targeted therapy resistance in pancreatic ductal adenocarcinoma (PDAC) are poorly understood. Here, we identify SETD5 as a major driver of PDAC resistance to MEK1/2 inhibition (MEKi). SETD5 is induced by MEKi resistance and its deletion restores refractory PDAC vulnerability to MEKi therapy in mouse models and patient-derived xenografts. SETD5 lacks histone methyltransferase activity but scaffolds a co-repressor complex, including HDAC3 and G9a. Gene silencing by the SETD5 complex regulates known drug resistance pathways to reprogram cellular responses to MEKi. Pharmacological co-targeting of MEK1/2, HDAC3, and G9a sustains PDAC tumor growth inhibition in vivo. Our work uncovers SETD5 as a key mediator of acquired MEKi therapy resistance in PDAC and suggests a context for advancing MEKi use in the clinic.

Topics: Animals; Apoptosis; Carcinoma, Pancreatic Ductal; Cell Proliferation; Chromatin; Drug Resistance, Neoplasm; Female; Histocompatibility Antigens; Histone Deacetylases; Histone-Lysine N-Methyltransferase; Humans; MAP Kinase Kinase 1; MAP Kinase Kinase 2; Methyltransferases; Mice; Mice, Inbred C57BL; Mice, Inbred NOD; Mice, SCID; Molecular Targeted Therapy; Pancreatic Neoplasms; Protein Kinase Inhibitors; Pyridones; Pyrimidinones; Small Molecule Libraries; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Pancreatic ductal adenocarcinoma (PDAC) is typically diagnosed at an advanced stage, which limits surgical options and portends a dismal prognosis. Current oncologic PDAC therapies confer marginal benefit and, thus, a significant unmet clinical need exists for new therapeutic strategies. To identify effective PDAC therapies, we leveraged a syngeneic orthotopic PDAC transplant mouse model to perform a large-scale, in vivo screen of 16 single-agent and 41 two-drug targeted therapy combinations in mice. Among 57 drug conditions screened, combined inhibition of heat shock protein (Hsp)-90 and MEK was found to produce robust suppression of tumor growth, leading to an 80% increase in the survival of PDAC-bearing mice with no significant toxicity. Mechanistically, we observed that single-agent MEK inhibition led to compensatory activation of resistance pathways, including components of the PI3K/AKT/mTOR signaling axis, which was overcome with the addition of HSP90 inhibition. The combination of HSP90(i) + MEK(i) was also active in vitro in established human PDAC cell lines and in vivo in patient-derived organoid PDAC transplant models. These findings encourage the clinical development of HSP90(i) + MEK(i) combination therapy and highlight the power of clinically relevant in vivo model systems for identifying cancer therapies.

Topics: Adenocarcinoma; Animals; Antineoplastic Agents; Benzodioxoles; Biomarkers, Tumor; Cell Line, Tumor; Disease Models, Animal; Drug Evaluation, Preclinical; Drug Screening Assays, Antitumor; Drug Synergism; Gene Expression; Humans; Immunohistochemistry; MAP Kinase Signaling System; Mice; Molecular Targeted Therapy; Pancreatic Neoplasms; Protein Kinase Inhibitors; Purines; Pyridones; Pyrimidinones; Signal Transduction; Survival Rate; Treatment Outcome; Xenograft Model Antitumor Assays

There is a wide variety of pancreatic neoplasms identified, but the great majority of them are of primary origin. Metastatic disease in the pancreatic parenchyma is quite rare (2-5% of pancreatic malignancies) and most often is quite difficult to differentiate from other primary lesions. Most of the imaging studies fail to give certain discriminating features for metastatic pancreatic neoplasms, contrary to endoscopic ultrasound and tissue sampling, which can provide an accurate diagnosis. In this report, we present a case of a male middle aged man who was admitted to our hospital with painless jaundice and finally was diagnosed with a cutaneous scalp melanoma dispersedly metastasized to the pancreas and upper gastrointestinal tract (stomach and duodenum).

Topics: Adrenal Gland Neoplasms; Antineoplastic Combined Chemotherapy Protocols; Brain Neoplasms; Cholangiopancreatography, Endoscopic Retrograde; Cranial Irradiation; Duodenal Neoplasms; Endoscopic Ultrasound-Guided Fine Needle Aspiration; Endoscopy, Digestive System; Endosonography; Humans; Imidazoles; Lung Neoplasms; Male; Melanoma; Middle Aged; Oximes; Pancreatic Neoplasms; Pyridones; Pyrimidinones; Skin Neoplasms; Stomach Neoplasms; Tomography, X-Ray Computed

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Cell Movement; Cell Proliferation; Cell Survival; Gene Expression Regulation, Neoplastic; Glycogen Synthase Kinase 3 beta; Humans; Inhibitory Concentration 50; Male; Mice; Pancreatic Neoplasms; Pharmacogenomic Testing; Pyridones; Pyrimidines; Pyrimidinones; Signal Transduction; Thiophenes; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

Topics: Cell Cycle Proteins; Deoxycytidine; Gemcitabine; Humans; Nuclear Proteins; Pancreatic Neoplasms; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; Pyrimidinones

According to results from a phase I/II trial, the investigational WEE1 inhibitor adavosertib combined with gemcitabine and radiation is well tolerated and may benefit patients with locally advanced pancreatic adenocarcinoma by increasing both systemic and local disease control.

Topics: Adenocarcinoma; Cell Cycle Proteins; Deoxycytidine; Gemcitabine; Humans; Nuclear Proteins; Pancreatic Neoplasms; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidinones

Although rare, NTRK gene fusions are known to be oncogenic drivers in pancreatic ductal adenocarcinoma (PDAC). We report the response of a metastatic CTRC-NTRK1 gene fusion-positive PDAC to targeted treatment with the oral tropomyosin receptor kinase (TRK) inhibitor larotrectinib and the eventual development of resistance to treatment.. A 61-year-old woman presented with a 2.5-cm mass in the body of the pancreas and a 1.2-cm liver lesion on routine follow-up for endometrial cancer that was in complete remission. Liver biopsy confirmed a primary PDAC unrelated to the endometrial cancer. The patient was treated with gemcitabine, nab-paclitaxel and ADI-PEG 20 for 12 months until disease progression and toxicity emerged [best overall response (BOR): partial response (PR)]. The patient switched to a modified regimen of folinic acid, fluorouracil, irinotecan and oxaliplatin for 4 months until neuropathy occurred. Oxaliplatin was withheld until disease progression 6 months later (BOR: stable disease). Despite recommencing oxaliplatin, the disease continued to progress. At this time, somatic profiling of the liver lesion revealed a CTRC-NTRK1 gene fusion. Treatment with larotrectinib 100 mg twice daily was commenced with BOR of PR at 2 months. The patient progressed after 6 months and was re-biopsied. Treatment was switched to the investigational next-generation TRK inhibitor selitrectinib (BAY 2731954, LOXO-195) 100 mg twice daily. After 2 months, the disease progressed and dabrafenibtrametinib combination therapy was initiated due to existence of a BRAF-V600E mutation. However, the cancer continued to progress and the patient died 2 months later.. Targeted TRK inhibition with larotrectinib in PDAC harbouring a CTRC-NTRK1 gene fusion is well tolerated and can improve quality of life for the patient. However, acquired resistance to therapy can emerge in some patients. Next-generation TRK inhibitors such as selitrectinib are currently in development to overcome this resistance (NCT02576431; NCT03215511).

Topics: Antineoplastic Combined Chemotherapy Protocols; Aza Compounds; Carcinoma, Pancreatic Ductal; Chymotrypsin; Female; Humans; Imidazoles; Middle Aged; Oncogene Proteins, Fusion; Oximes; Pancreatic Neoplasms; Protein Kinase Inhibitors; Protein Kinases; Pyrazoles; Pyridones; Pyrimidines; Pyrimidinones; Receptor, trkA

To determine the role of BRAF

Topics: Aged; Animals; Antineoplastic Agents; Apoptosis; Carcinoma, Neuroendocrine; Cell Line, Tumor; Colorectal Neoplasms; Exons; Female; Follow-Up Studies; G1 Phase Cell Cycle Checkpoints; Humans; Imidazoles; Intestinal Neoplasms; Male; MAP Kinase Signaling System; Mice; Mice, Inbred NOD; Middle Aged; Mitogen-Activated Protein Kinase Kinases; Mutation; Neuroendocrine Tumors; Oximes; Pancreatic Neoplasms; Phosphorylation; Proto-Oncogene Proteins B-raf; Pyridones; Pyrimidinones; Stomach Neoplasms; Survival Analysis; Tissue Array Analysis; Vemurafenib; Xenograft Model Antitumor Assays

Distal regulatory elements influence the activity of gene promoters through chromatin looping. Chromosome conformation capture (3C) methods permit identification of chromatin contacts across different regions of the genome. However, due to limitations in the resolution of these methods, the detection of functional chromatin interactions remains a challenge. In the current study, we employ an integrated approach to define and characterize the functional chromatin contacts of human pancreatic cancer cells. We applied tethered chromatin capture to define classes of chromatin domains on a genome-wide scale. We identified three types of structural domains (topologically associated, boundary, and gap) and investigated the functional relationships of these domains with respect to chromatin state and gene expression. We uncovered six distinct sub-domains associated with epigenetic states. Interestingly, specific epigenetically active domains are sensitive to treatment with histone acetyltransferase (HAT) inhibitors and decrease in H3K27 acetylation levels. To examine whether the subdomains that change upon drug treatment are functionally linked to transcription factor regulation, we compared TCF7L2 chromatin binding and gene regulation to HAT inhibition. We identified a subset of coding RNA genes that together can stratify pancreatic cancer patients into distinct survival groups. Overall, this study describes a process to evaluate the functional features of chromosome architecture and reveals the impact of epigenetic inhibitors on chromosome architecture and identifies genes that may provide insight into disease outcome.

Topics: Benzoates; Bridged Bicyclo Compounds, Heterocyclic; Cell Line, Tumor; Chromatin; Chromatin Assembly and Disassembly; Chromosome Mapping; Epigenesis, Genetic; Epigenomics; Gene Expression Regulation, Neoplastic; Gene Regulatory Networks; Humans; Nitrobenzenes; Pancreatic Neoplasms; Pyrazoles; Pyrazolones; Pyrimidinones; Transcription Factor 7-Like 2 Protein

Topics: Animals; Autophagy; CA-19-9 Antigen; Cell Line, Tumor; Chloroquine; Humans; MAP Kinase Signaling System; Mice, SCID; Mitogen-Activated Protein Kinase Kinases; Pancreatic Neoplasms; Protein Kinase Inhibitors; Proto-Oncogene Proteins B-raf; Pyridones; Pyrimidinones; ras Proteins; Xenograft Model Antitumor Assays

Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Cycle; Cell Proliferation; Colorectal Neoplasms; Drug Therapy, Combination; Female; Humans; Mice; Mice, Nude; Mutation; Pancreatic Neoplasms; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins p21(ras); Pyridones; Pyrimidinones; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Clinical trials of EGFR inhibitors in combination with gemcitabine for the treatment of pancreatic ductal adenocarcinoma (PDAC) have generated mixed results partially due to the poorly defined effectiveness of EGFR inhibitors in PDAC. Here, we studied a panel of PDAC cell lines to compare the IC50s of the EGFR inhibitors gefitinib and cetuximab. We found that gefitinib induced biphasic inhibition in over 50% of PDAC cells, with the initial growth inhibition occurring at nanomolar concentrations and a second growth inhibition occurring outside the clinical range. In contrast to gefitinib, cetuximab produced a single phase growth inhibition in a subset of PDAC cells. Using this sensitivity data, we screened for correlations between cell morphology proteins and EGFR ligands to EGFR inhibitor sensitivity, and found that mesothelin and the EGFR ligand TGF-α have a strong correlation to gefitinib and cetuximab sensitivity. Analysis of downstream signaling pathways indicated that plc-γ1 and c-myc were consistently inhibited by EGFR inhibitor treatment in sensitive cell lines. While an inconsistent additive effect was observed with either cetuximab or gefitinib in combination with gemcitabine, the cell pathway data indicated consistent ERK activation, leading us to pursue EGFR inhibitors in combination with trametinib, a MEK1/2 inhibitor. Both cetuximab and gefitinib in combination with trametinib produced an additive effect in all EGFR sensitive cell lines. Our results indicate that mesothelin and TGF-α can predict PDAC sensitivity to EGFR inhibitors and a combination of EGFR inhibitors with trametinib could be a novel effective treatment for PDAC.

Topics: Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Pancreatic Ductal; Cell Cycle; Cell Proliferation; Cetuximab; Drug Resistance, Neoplasm; ErbB Receptors; Gefitinib; GPI-Linked Proteins; Humans; Mesothelin; Pancreatic Neoplasms; Pyridones; Pyrimidinones; Signal Transduction; Transforming Growth Factor alpha; Tumor Cells, Cultured

Oncogenic K-Ras signaling highly relies on the canonical Ras/MEK/ERK pathway to contribute to pancreatic cancer progression. However, numerous efforts of MEK inhibitors have failed to provide an optimal antitumor effect for pancreatic cancer in practice. The aim of the present work was to develop a more efficacious therapeutic intervention for MEK inhibitors through combination with histone deacetylase (HDAC) inhibitor MPT0E028.. The effects of combined therapy on cell viability, apoptosis, protein, and RNA expressions were determined by MTT assay, flow cytometry, western blotting, and quantitative PCR analysis. The AsPC-1 xenograft was used to assess antitumor effects in vivo.. The co-administration of MPT0E028 and MEK inhibitor yielded synergistic effects on cell viability suppression both in K-Ras mutated and wild-type pancreatic cancer cells and also markedly triggered cell apoptosis. Surprisingly, ERK and epidermal growth factor receptor (EGFR) were activated by the long-term and low-concentration treatment of MPT0E028 or another HDAC inhibitor alone. Whereas, the pharmacological attenuation of ERK signaling dramatically abolished the MPTE028-induced p-ERK and EGFR expression. Overexpression of HDAC4, HDAC6, and MEK, respectively, reversed the cell death induced by the combined treatment. Finally, the combined treatment decreased the tumor volume in an AsPC-1 xenograft model compared to each individual treatment alone.. The synergistic anti-survival effect of the combination was suggested to occur via compensation of the MEK inhibitor for activated ERK. Our results indicate that this combination strategy could benefit patients with pancreatic cancer beyond K-Ras status.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Cell Line, Tumor; Cell Proliferation; Cell Survival; Drug Synergism; Epigenesis, Genetic; ErbB Receptors; Flavonoids; Gene Expression Regulation, Neoplastic; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Indoles; Male; Mice; Pancreatic Neoplasms; Protein Kinase Inhibitors; Proto-Oncogene Proteins p21(ras); Pyridones; Pyrimidinones; Xenograft Model Antitumor Assays

Standard chemotherapy for pancreatic ductal adenocarcinoma (PDAC), nab-paclitaxel (NPT) plus gemcitabine (Gem), has led to an average survival of 8.5 months. Presently, no therapeutics exist that effectively target the KRAS oncogene, activated in 95% of PDACs, but alternative strategies focus on inhibition of downstream effectors of KRAS signaling. Through combined inhibition of PI3K and MAPK signaling with MK-2206 (MK) and trametinib (Tra), enhancement of NPT + Gem response was evaluated. Median animal survival was significantly improved by the NPT + Gem combination (67% increase). Addition of MK-2206 or trametinib further increased median survival: NPT + Gem + MK (86%), NPT + Gem + Tra (105%), and NPT + Gem + MK + Tra (129%). In cell line-derived xenografts, the net tumor growth (in mm

Topics: Albumins; Animals; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Cell Proliferation; Deoxycytidine; Drug Synergism; Female; Gemcitabine; Heterocyclic Compounds, 3-Ring; Humans; MAP Kinase Signaling System; Mice; Mice, Inbred NOD; Mice, SCID; Paclitaxel; Pancreatic Neoplasms; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Pyridones; Pyrimidinones; Xenograft Model Antitumor Assays

Advances in therapies targeting proteins and pathways affected by genetic alterations has raised the possibility of personalized cancer treatments.. The efficacy of targeting molecular aberrations was determined in the pancreatic ductal adenocarcinoma (PDAC) cell line, CAPAN2. Two mutations were targeted, KRAS (p.G12V) and ABL1 (p.G1060D), and cells were treated with regorafenib and trametinib, individually and in combination.. Exposure to either drug significantly increased cell death compared to the current standard of care, gemcitabine. Treatment with combinations of the drugs led to significant increases in cell death compared to either monotherapy. Strong additive/synergistic interactions were observed across a range of dosages and ratios, reducing dose requirements with potential clinical relevance.. The data obtained in this PDAC cell model: i) support the use of matched monotherapies; ii) indicate the effectiveness of matched combination therapies; and iii) provide potential proof-of-concept for precision medicine approach to cancer treatment.

Topics: Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Deoxycytidine; Drug Synergism; Gemcitabine; Humans; Pancreatic Neoplasms; Phenylurea Compounds; Piperazines; Protein Kinase Inhibitors; Pyridines; Pyridones; Pyrimidinones

Pancreatic cancer is resistant to treatment and needs precision individualized therapy to improve the outcome of this disease. Previously, we demonstrated that trametinib (TRA), a MEK inhibitor, could inhibit a pancreatic cancer patient-derived orthotopic xenograft (PDOX). In the present study, we show that gemcitabine (GEM) in combination with TRA was more effective than TRA alone. We implanted a patient pancreatic cancer orthotopically in the pancreatic tail of nude mice to establish the PDOX model. After seven weeks of tumor growth, we divided 32 pancreatic-cancer PDOX nude mice into 4 groups of eight: untreated control; GEM (once a week for 2 weeks); TRA (14 consecutive days); GEM + TRA (GEM: once a week for 2 weeks, TRA:14 consecutive days). We found that treated mice on day 14 had significantly reduced tumor volume in comparison to untreated control. TRA and the combination of GEM + TRA therapy significantly inhibited tumor development in comparison to GEM alone. However, GEM + TRA inhibited the PDOX tumor growth significantly greater than TRA alone. These results suggest the clinical potential of the combination of TRA and GEM for pancreatic cancer.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Deoxycytidine; Disease Models, Animal; Gemcitabine; Humans; Mice; Mice, Nude; Pancreatic Neoplasms; Pyridones; Pyrimidinones; Xenograft Model Antitumor Assays

Small molecule inhibitors of the checkpoint proteins CHK1 and WEE1 are currently in clinical development in combination with the antimetabolite gemcitabine. It is unclear, however, if there is a therapeutic advantage to CHK1 vs. WEE1 inhibition for chemosensitization. The goals of this study were to directly compare the relative efficacies of the CHK1 inhibitor MK8776 and the WEE1 inhibitor AZD1775 to sensitize pancreatic cancer cell lines to gemcitabine and to identify pharmacodynamic biomarkers predictive of chemosensitization. Cells treated with gemcitabine and either MK8776 or AZD1775 were first assessed for clonogenic survival. With the exception of the homologous recombination-defective Capan1 cells, which were relatively insensitive to MK8776, we found that these cell lines were similarly sensitized to gemcitabine by CHK1 or WEE1 inhibition. The abilities of either the CDK1/2 inhibitor roscovitine or exogenous nucleosides to prevent MK8776 or AZD1775-mediated chemosensitization, however, were both inhibitor-dependent and variable among cell lines. Given the importance of DNA replication stress to gemcitabine chemosensitization, we next assessed high-intensity, pan-nuclear γH2AX staining as a pharmacodynamic marker for sensitization. In contrast to total γH2AX, aberrant mitotic entry or sub-G1 DNA content, high-intensity γH2AX staining correlated with chemosensitization by either MK8776 or AZD1775 (R

Topics: Analysis of Variance; Biomarkers, Tumor; Cell Cycle Checkpoints; Cell Cycle Proteins; Cell Line, Tumor; Cell Survival; Checkpoint Kinase 1; Deoxycytidine; DNA Replication; Gemcitabine; Histones; Humans; Nucleosides; Pancreatic Neoplasms; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; Pyrimidinones; Roscovitine; Staining and Labeling

Although therapies for advanced melanoma have been greatly improved by the development of immune checkpoint inhibitors and BRAF/mitogen-activated protein kinase kinase inhibitors, there are still many concerns about the administration of these novel drugs. Therefore, to combine these therapies sequentially at appropriate time points of the disease is important. In this report, we report two cases in which dabrafenib and trametinib therapy for advanced melanoma failed but were successfully controlled by nivolumab monotherapy, and investigated the sera sCD163, CCL22 and CXCL10 as biomarkers for tumor progression. Interestingly, the sera levels of sCD163, CXCL10 and CCL22, both of which are produced by activated tumor-associated macrophages, were increased in parallel with the tumor progression in each case. Because this report presents only two cases, further data will need to be accumulated to provide more fundamental insights into the usefulness of these biomarkers for predicting disease progression in melanoma.

Topics: Adult; Antineoplastic Agents, Immunological; Antineoplastic Combined Chemotherapy Protocols; Bile Duct Neoplasms; Disease Progression; Female; Humans; Imidazoles; Lymphatic Metastasis; Male; Melanoma; Middle Aged; Nivolumab; Oximes; Pancreatic Neoplasms; Protein Kinase Inhibitors; Pyridones; Pyrimidinones; Skin Neoplasms; Treatment Outcome

A pancreatic ductal adenocarcinoma (PDAC), obtained from a patient, was grown orthotopically in the pancreatic tail of nude mice to establish a patient-derived orthotopic (PDOX) model. Seven weeks after implantation, PDOX nude mice were divided into the following groups: untreated control (n = 7); gemcitabine (100 mg/kg, i.p., once a week for 2 weeks, n = 7); cobimetinib (5 mg/kg, p.o., 14 consecutive days, n = 7); trametinib (0.3 mg/kg, p.o., 14 consecutive days, n = 7); trabectedin (0.15 mg/kg, i.v., once a week for 2 weeks, n = 7); temozolomide (25 mg/kg, p.o., 14 consecutive days, n = 7); carfilzomib (2 mg/kg, i.v., twice a week for 2 weeks, n = 7); bortezomib (1 mg/kg, i.v., twice a week for 2 weeks, n = 7); MK-1775 (20 mg/kg, p.o., 14 consecutive days, n = 7); BEZ-235 (45 mg/kg, p.o., 14 consecutive days, n = 7); vorinostat (50 mg/kg, i.p., 14 consecutive days, n = 7). Only the MEK inhibitors, cobimetinib and trametinib, regressed tumor growth, and they were more significantly effective than other therapies (p < 0.0001, respectively), thereby demonstrating the precision of the PDOX models of PDAC and its potential for individualizing pancreatic-cancer therapy.

Topics: Animals; Antineoplastic Agents; Azetidines; Cell Line, Tumor; Deoxycytidine; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Resistance, Neoplasm; Gemcitabine; Humans; Mice; Mitogen-Activated Protein Kinases; Pancreatic Neoplasms; Piperidines; Protein Kinase Inhibitors; Pyridones; Pyrimidinones; Xenograft Model Antitumor Assays

Topics: Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Pancreatic Ductal; Cell Growth Processes; Drug Synergism; Heterocyclic Compounds, 3-Ring; Humans; MAP Kinase Kinase Kinases; Morpholines; Pancreatic Neoplasms; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Protein Kinase Inhibitors; Pyridones; Pyrimidinones; Triazines

Pancreatic cancer is an increasing cause of cancer related death worldwide. KRAS is the dominant oncogene in this cancer type and molecular rationale would indicate, that inhibitors of the downstream target MEK could be appropriate targeted agents, but clinical trials have failed so far to achieve statistically significant benefit in unselected patients. We aimed to identify predictive molecular biomarkers that can help to define subgroups where MEK inhibitors might be beneficial alone or in combination. Next-generation sequencing data of 50 genes in three pancreatic cancer cell lines (MiaPaCa2, BxPC3 and Panc1) were analyzed and compared to the molecular profile of 138 clinical pancreatic cancer samples to identify the molecular subtypes of pancreatic cancer these cell lines represent. Luminescent cell viability assay was used to determine the sensitivity of cell lines to kinase inhibitors. Western blot was used to analyze the pathway activity of the examined cell lines. According to our cell viability and pathway activity data on these model cell lines only cells harboring the rare G12C KRAS mutation and low EGFR expression are sensitive to single MEK inhibitor (trametinib) treatment. The common G12D KRAS mutation leads to elevated baseline Akt activity, thus treatment with single MEK inhibitors fails. However, combination of MEK and Akt inhibitors are synergistic in this case. In case of wild-type KRAS and high EGFR expression MEK inhibitor induced Akt phosphorylation leads to trametinib resistance which necessitates for MEK and EGFR or Akt inhibitor combination treatment. In all we provide strong preclinical rational and possible molecular mechanism to revisit MEK inhibitor therapy in pancreatic cancer in both monotherapy and combination, based on molecular profile analysis of pancreatic cancer samples and cell lines. According to our most remarkable finding, a small subgroup of patients with G12C KRAS mutation may still benefit from MEK inhibitor monotherapy.

Topics: Cell Line, Tumor; ErbB Receptors; Genes, ras; Humans; MAP Kinase Kinase Kinases; Mutation; Pancreatic Neoplasms; Protein Kinase Inhibitors; Pyridones; Pyrimidinones; Signal Transduction

Activating mutations in the proto-oncogene KRAS are a hallmark of pancreatic ductal adenocarcinoma (PDAC), an aggressive malignancy with few effective therapeutic options. Despite efforts to develop KRAS-targeted drugs, the absolute dependence of PDAC cells on KRAS remains incompletely understood. Here we model complete KRAS inhibition using CRISPR/Cas-mediated genome editing and demonstrate that KRAS is dispensable in a subset of human and mouse PDAC cells. Remarkably, nearly all KRAS deficient cells exhibit phosphoinositide 3-kinase (PI3K)-dependent mitogen-activated protein kinase (MAPK) signaling and induced sensitivity to PI3K inhibitors. Furthermore, comparison of gene expression profiles of PDAC cells retaining or lacking KRAS reveal a role of KRAS in the suppression of metastasis-related genes. Collectively, these data underscore the potential for PDAC resistance to even the very best KRAS inhibitors and provide insights into mechanisms of response and resistance to KRAS inhibition.

Topics: Animals; Antineoplastic Agents; Benzimidazoles; Carcinoma, Pancreatic Ductal; DNA Copy Number Variations; Humans; Immunoblotting; Indazoles; Mice; Morpholines; Pancreatic Neoplasms; Phenylurea Compounds; Piperidines; Proto-Oncogene Mas; Proto-Oncogene Proteins p21(ras); Purines; Pyrimidines; Pyrimidinones; Quinazolinones; Sulfonamides; Thiazoles

Most patients with pancreatic ductal adenocarcinoma (PDAC) die within 5 years following resection plus adjuvant gemcitabine (Gem) from outgrowth of occult metastases. We hypothesized that inhibition of the KRAS pathway with the MEK inhibitor trametinib would inhibit the outgrowth of occult liver metastases in a preclinical model.. Liver metastases harvested from two patients with PDAC (Tumors 608, 366) were implanted orthotopically in mice. Tumor cell lines were derived and transduced with lentiviruses encoding luciferase and injected into spleens of mice generating microscopic liver metastases. Growth kinetics of liver metastases were measured with bioluminescent imaging and time-to-progression (TTP), progression-free survival (PFS), and overall survival (OS) were determined.. Trametinib (0.3 mg/kg BID) significantly prolonged OS versus control (Tumor 608: 114 vs. 43 days, p < 0.001; Tumor 366: not reached vs. 167 days, p = 0.0488). In vivo target validation demonstrated trametinib significantly reduced phosphorylated-ERK and expression of the ERK-responsive gene DUSP6. In a randomized, preclinical trial, mice were randomized to: (1) control, (2) adjuvant Gem (100 mg/kg IP, Q3 days) × 7 days followed by surveillance, or (3) adjuvant Gem followed by trametinib. Sequential Gem-trametinib significantly decreased metastatic cell outgrowth and increased TTP and PFS.. Treatment of mice bearing micrometastases with trametinib significantly delayed tumor outgrowth by effectively inhibiting KRAS-MEK-ERK signaling. In a randomized, preclinical, murine trial adjuvant sequential Gem followed by trametinib inhibited occult metastatic cell outgrowth in the liver and increased PFS versus adjuvant Gem alone. An adjuvant trial of sequential Gem-trametinib is being planned in patients with resected PDAC.

Topics: Animals; Carcinoma, Pancreatic Ductal; Humans; Liver Neoplasms; Mice; Pancreatic Neoplasms; Protein Kinase Inhibitors; Pyridones; Pyrimidinones; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

The Wee1 kinase, which is activated in response to DNA damage, regulates exit from G2 through inhibitory phosphorylation of Cdk1/Cdc2, and is an attractive drug target. However, recent work has highlighted effects of Cdk2 phosphorylation by Wee1 on movement through S-phase, suggesting the potential to sensitize to S-phase specific agents by Wee1 inhibitors. In this paper we applied multiparametric flow cytometry to patient-derived pancreatic cancer xenograft tumor cells to study the cell cycle perturbations of Wee1 disruption via the small molecule inhibitor MK-1775, and genetic knockdown. We find that in vitro treatment with MK-1775, and to a lesser degree, Wee1 RNA transcript knockdown, results in the striking appearance of S-phase cells prematurely entering into mitosis. This effect was not seen in vivo in any of the models tested. Here, although we noted an increase of S-phase cells expressing the damage response marker γH2AX, treatment with MK-1775 did not significantly sensitize cells to the cytidine analog gemcitabine. Treatment with MK-1775 did result in a transient but large increase in cells expressing the mitotic marker phosphorylated H3S10 that reached a peak 4 hours after treatment. This suggests a role for Wee1 regulating the progression of genomically unstable cancer cells through G2 in the absence of extrinsically-applied DNA damage. A single dose of 8Gy ionizing radiation resulted in the time-dependent accumulation of Cyclin A2 positive/phosphorylated H3S10 negative cells at the 4N position, which was abrogated by treatment with MK-1775. Consistent with these findings, a genome-scale pooled RNA interference screen revealed that toxic doses of MK-1775 are suppressed by CDK2 or Cyclin A2 knockdown. These findings support G2 exit as the more significant effect of Wee1 inhibition in pancreatic cancers.

Topics: Animals; Cell Cycle; Cell Cycle Proteins; Cell Line, Tumor; Cell Proliferation; Cyclin A2; Cyclin-Dependent Kinase 2; DNA Damage; Flow Cytometry; Gene Expression Regulation, Neoplastic; Humans; Mice; Mitosis; Nuclear Proteins; Pancreatic Neoplasms; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; Pyrimidinones; Xenograft Model Antitumor Assays

Pancreatic ductal adenocarcinoma (PDAC) is a highly deadly malignancy. Expression of the stem cell transcription factor SOX2 increases during progression of PDAC. Knockdown of SOX2 in PDAC cell lines decreases growth in vitro; whereas, stable overexpression of SOX2 in one PDAC cell line reportedly increases growth in vitro. Here, we reexamined the role of SOX2 in PDAC cells, because inducible SOX2 overexpression in other tumor cell types inhibits growth. In this study, four PDAC cell lines were engineered for inducible overexpression of SOX2 or inducible knockdown of SOX2. Remarkably, inducible overexpression of SOX2 in PDAC cells inhibits growth in vitro and reduces tumorigenicity. Additionally, inducible knockdown of SOX2 in PDAC cells reduces growth in vitro and in vivo. Thus, growth and tumorigenicity of PDAC cells is highly dependent on the expression of optimal levels of SOX2 - a hallmark of molecular rheostats. We also determined that SOX2 alters the responses of PDAC cells to drugs used in PDAC clinical trials. Increasing SOX2 reduces growth inhibition mediated by MEK and AKT inhibitors; whereas knockdown of SOX2 further reduces growth when PDAC cells are treated with these inhibitors. Thus, targeting SOX2, or its mode of action, could improve the treatment of PDAC.

Topics: Adenocarcinoma; Animals; Antineoplastic Agents; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Cell Proliferation; Doxorubicin; Female; Heterocyclic Compounds, 3-Ring; Humans; Mice; Mice, Nude; Mitogen-Activated Protein Kinase Kinases; Pancreatic Neoplasms; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins p21(ras); Pyridones; Pyrimidinones; RNA Interference; RNA, Small Interfering; SOXB1 Transcription Factors

Therapeutic targeting of KRAS-mutant lung adenocarcinoma represents a major goal of clinical oncology. KRAS itself has proved difficult to inhibit, and the effectiveness of agents that target key KRAS effectors has been thwarted by activation of compensatory or parallel pathways that limit their efficacy as single agents. Here we take a systematic approach towards identifying combination targets for trametinib, a MEK inhibitor approved by the US Food and Drug Administration, which acts downstream of KRAS to suppress signalling through the mitogen-activated protein kinase (MAPK) cascade. Informed by a short-hairpin RNA screen, we show that trametinib provokes a compensatory response involving the fibroblast growth factor receptor 1 (FGFR1) that leads to signalling rebound and adaptive drug resistance. As a consequence, genetic or pharmacological inhibition of FGFR1 in combination with trametinib enhances tumour cell death in vitro and in vivo. This compensatory response shows distinct specificities: it is dominated by FGFR1 in KRAS-mutant lung and pancreatic cancer cells, but is not activated or involves other mechanisms in KRAS wild-type lung and KRAS-mutant colon cancer cells. Importantly, KRAS-mutant lung cancer cells and patients’ tumours treated with trametinib show an increase in FRS2 phosphorylation, a biomarker of FGFR activation; this increase is abolished by FGFR1 inhibition and correlates with sensitivity to trametinib and FGFR inhibitor combinations. These results demonstrate that FGFR1 can mediate adaptive resistance to trametinib and validate a combinatorial approach for treating KRAS-mutant lung cancer.

Topics: Adenocarcinoma; Adenocarcinoma of Lung; Animals; Antineoplastic Combined Chemotherapy Protocols; Cell Death; Cell Proliferation; Colonic Neoplasms; Disease Models, Animal; Drug Resistance, Neoplasm; Drug Screening Assays, Antitumor; Enzyme Activation; Feedback, Physiological; Female; Humans; Imidazoles; Lung Neoplasms; MAP Kinase Signaling System; Mice; Mitogen-Activated Protein Kinase Kinases; Mutant Proteins; Mutation; Pancreatic Neoplasms; Phosphorylation; Proto-Oncogene Proteins p21(ras); Pyridazines; Pyridones; Pyrimidinones; Receptor, Fibroblast Growth Factor, Type 1; Xenograft Model Antitumor Assays

Pancreatic ductal adenocarcinoma (PDAC) harbors the worst prognosis of any common solid tumor, and multiple failed clinical trials indicate therapeutic recalcitrance. Here, we use exome sequencing of patient tumors and find multiple conserved genetic alterations. However, the majority of tumors exhibit no clearly defined therapeutic target. High-throughput drug screens using patient-derived cell lines found rare examples of sensitivity to monotherapy, with most models requiring combination therapy. Using PDX models, we confirmed the effectiveness and selectivity of the identified treatment responses. Out of more than 500 single and combination drug regimens tested, no single treatment was effective for the majority of PDAC tumors, and each case had unique sensitivity profiles that could not be predicted using genetic analyses. These data indicate a shortcoming of reliance on genetic analysis to predict efficacy of currently available agents against PDAC and suggest that sensitivity profiling of patient-derived models could inform personalized therapy design for PDAC.

Topics: Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Dasatinib; Docetaxel; Drug Resistance, Neoplasm; Everolimus; Exome; Humans; Mice; Models, Genetic; Models, Statistical; Pancreatic Neoplasms; Precision Medicine; Prognosis; Pyridones; Pyrimidinones; Taxoids; Xenograft Model Antitumor Assays

Pancreatic ductal adenocarcinoma (PDA) is a lethal disease, in part, because of the lack of effective targeted therapeutic options. MK-1775 (also known as AZD1775), a mitotic inhibitor, has been demonstrated to enhance the anti-tumor effects of DNA damaging agents such as gemcitabine. We evaluated the efficacy of MK-1775 alone or in combination with DNA damaging agents (MMC or oxaliplatin) in PDA cell lines that are either DNA repair proficient (DDR-P) or deficient (DDR-D). PDA cell lines PL11, Hs 766T and Capan-1 harboring naturally selected mutations in DNA repair genes FANCC, FANCG and BRCA2 respectively, were less sensitive to MK-1775 as compared to two out of four representative DDR-P (MIA PaCa2 and PANC-1) cell lines. Accordingly, DDR-P cells exhibit reduced sensitivity to MK-1775 upon siRNA silencing of DNA repair genes, BRCA2 or FANCD2, compared to control cells. Only DDR-P cells showed increased apoptosis as a result of early mitotic entry and catastrophe compared to DDR-D cells. Taken together with other recently published reports, our results add another level of evidence that the efficacy of WEE1 inhibition is influenced by the DNA repair status of a cell and may also be dependent on the tumor type and model evaluated.

Topics: Antineoplastic Agents; Apoptosis; Carcinoma, Pancreatic Ductal; Cell Cycle Proteins; Cell Line, Tumor; DNA Damage; DNA Repair; DNA Repair Enzymes; Drug Resistance, Neoplasm; Drug Synergism; Humans; Inhibitory Concentration 50; Mitomycin; Mitosis; Mutagens; Mutation; Nuclear Proteins; Organoplatinum Compounds; Oxaliplatin; Pancreatic Neoplasms; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; Pyrimidinones

Topics: Adenocarcinoma; Antineoplastic Combined Chemotherapy Protocols; Biopsy; DNA Mutational Analysis; Humans; Imidazoles; Immunohistochemistry; Male; MAP Kinase Kinase Kinases; Melanoma; Middle Aged; Molecular Targeted Therapy; Mutation; Oximes; Pancreatic Neoplasms; Positron-Emission Tomography; Predictive Value of Tests; Protein Kinase Inhibitors; Proto-Oncogene Proteins; Proto-Oncogene Proteins B-raf; Proto-Oncogene Proteins p21(ras); Pyridones; Pyrimidinones; ras Proteins; Risk Factors; Skin Neoplasms; Time Factors; Tomography, X-Ray Computed; Treatment Outcome

Pancreatic cancer remains a clinical challenge, thus new therapies are urgently needed. The selective Wee1 inhibitor MK-1775 has demonstrated promising results when combined with DNA damaging agents, and more recently with CHK1 inhibitors in various malignancies. We have previously demonstrated that treatment with the pan-histone deacetylase inhibitor panobinostat (LBH589) can cause down-regulation of CHK1. Accordingly, we investigated using panobinostat to down-regulate CHK1 in combination with MK-1775 to enhance cell death in preclinical pancreatic cancer models. We demonstrate that MK-1775 treatment results in increased H2AX phosphorylation, indicating increased DNA double-strand breaks, and activation of CHK1, which are both dependent on CDK activity. Combination of MK-1775 and panobinostat resulted in synergistic antitumor activity in six pancreatic cancer cell lines. Finally, our in vivo study using a pancreatic xenograft model reveals promising cooperative antitumor activity between MK-1775 and panobinostat. Our study provides compelling evidence that the combination of MK-1775 and panobinostat has antitumor activity in preclinical models of pancreatic cancer and supports the clinical development of panobinostat in combination with MK-1775 for the treatment of this deadly disease.

Topics: Animals; Apoptosis; Blotting, Western; Cell Cycle; Cell Cycle Proteins; Cell Proliferation; DNA Damage; Drug Interactions; Drug Synergism; Female; Histone Deacetylase Inhibitors; Humans; Hydroxamic Acids; Immunoenzyme Techniques; Indoles; Mice; Mice, Inbred BALB C; Mice, Nude; Nuclear Proteins; Pancreatic Neoplasms; Panobinostat; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; Pyrimidinones; Real-Time Polymerase Chain Reaction; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; RNA, Small Interfering; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

Over 90% of pancreatic adenocarcinoma PC express oncogenic mutant KRAS that constitutively activates the Raf-MEK-MAPK pathway conferring resistance to both radiation and chemotherapy. MEK inhibitors have shown promising anti-tumor responses in recent preclinical and clinical studies, and are currently being tested in combination with radiation in clinical trials. Here, we have evaluated the radiosensitizing potential of a novel MEK1/2 inhibitor GSK1120212 (GSK212,or trametinib) and evaluated whether MEK1/2 inhibition alters DNA repair mechanisms in multiple PC cell lines.. Radiosensitization and DNA double-strand break (DSB) repair were evaluated by clonogenic assays, comet assay, nuclear foci formation (γH2AX, DNA-PK, 53BP1, BRCA1, and RAD51), and by functional GFP-reporter assays for homologous recombination (HR) and non-homologous end-joining (NHEJ). Expression and activation of DNA repair proteins were measured by immunoblotting.. GSK212 blocked ERK1/2 activity and radiosensitized multiple KRAS mutant PC cell lines. Prolonged pre-treatment with GSK212 for 24-48 hours was required to observe significant radiosensitization. GSK212 treatment resulted in delayed resolution of DNA damage by comet assays and persistent γH2AX nuclear foci. GSK212 treatment also resulted in altered BRCA1, RAD51, DNA-PK, and 53BP1 nuclear foci appearance and resolution after radiation. Using functional reporters, GSK212 caused repression of both HR and NHEJ repair activity. Moreover, GSK212 suppressed the expression and activation of a number of DSB repair pathway intermediates including BRCA1, DNA-PK, RAD51, RRM2, and Chk-1.. GSK212 confers radiosensitization to KRAS-driven PC cells by suppressing major DNA-DSB repair pathways. These data provide support for the combination of MEK1/2 inhibition and radiation in the treatment of PC.

Topics: Adenocarcinoma; Antineoplastic Agents; Cell Line, Tumor; DNA Breaks, Double-Stranded; DNA Repair; Gene Expression Regulation, Neoplastic; Humans; MAP Kinase Signaling System; Pancreatic Neoplasms; Phosphorylation; Protein Kinase Inhibitors; Proto-Oncogene Proteins p21(ras); Pyridones; Pyrimidinones; Radiation Tolerance

Recently, the transient receptor potential melastatin 8 (TRPM8) channel has emerged as a putative biomarker for pancreatic ductal adenocarcinoma (PDA). This study aimed to evaluate the expression of TRPM8 and its modulation by specific agonists and antagonists in PDA cells.. We examined the protein expression of TRPM8 in 3 different PDA cell lines and compared it with a nontumoral epithelial cell line of human pancreatic origin using Western blotting and immunocytochemical analysis. To assess the function of TRPM8 channels, we measured the TRPM8 currents in whole-cell mode of the patch clamp technique. To explore the putative involvement of TRPM8 in cell migration, we investigated the motility of PDA cells using the scratch-wound assay.. Pancreatic ductal adenocarcinoma cells express functional plasma membrane TRPM8 channels, which are responsive after exposure to agonists (menthol and icilin) and antagonists N-(3-aminopropyl)-2-{[(3-methylphenyl) methyl]oxy}-N-(2-thienylmethyl)benzamide hydrochloride salt. The silencing of TRPM8 expression by small interfering RNA augments the migration of PDA cells. Conversely, the activated form of TRPM8 inhibits PDA cell motility.. An unglycosylated TRPM8 protein is expressed and is functional in the membrane of PDA cells. Transient receptor potential melastatin 8 inhibits the migration of PDA cells, suggesting a putative role as a biomarker or target for this channel for PDA therapy.

Topics: Adenocarcinoma; Benzamides; Blotting, Western; Carcinoma, Pancreatic Ductal; Cell Line; Cell Line, Tumor; Cell Membrane; Cell Movement; HEK293 Cells; Humans; Immunohistochemistry; Membrane Potentials; Membrane Proteins; Menthol; Pancreatic Neoplasms; Patch-Clamp Techniques; Pyrimidinones; RNA Interference; Thiophenes; TRPM Cation Channels

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal cancer due in part to a lack of highly robust cytotoxic or molecular-based therapies. Recent studies investigating ligand-mediated Wnt/β-catenin signaling have highlighted its importance in pancreatic cancer initiation and progression, as well as its potential as a therapeutic target in PDAC. The small-molecule ICG-001 binds cAMP-responsive element binding (CREB)-binding protein (CBP) to disrupt its interaction with β-catenin and inhibit CBP function as a coactivator of Wnt/β-catenin-mediated transcription. Given its ability to inhibit Wnt/β-catenin-mediated transcription in vitro and in vivo, as well as its efficacy in preclinical models of colorectal cancer and other Wnt-driven diseases, we examined ICG-001 and its potential role as a therapeutic in PDAC. ICG-001 alone significantly inhibited anchorage-dependent and -independent growth of multiple PDAC lines, and augmented in vitro growth inhibition when used in combination with gemcitabine. ICG-001 had only variable modest effects on PDAC apoptosis and instead mediated PDAC growth inhibition primarily through robust induction of G₁ cell-cycle arrest. These effects, however, seemed decoupled from its inhibition of Wnt/β-catenin-mediated transcription. DNA microarrays performed on PDAC cells in the context of ICG-001 treatment revealed ICG-001 altered the expression of several genes with well-established roles in DNA replication and cell-cycle progression, including direct actions on SKP2 and CDKN1A. ICG-001 also significantly prolonged survival in an in vivo orthotopic xenograft model of PDAC, indicating ICG-001 or derived compounds that disrupt CBP activity are potentially useful small-molecule therapeutics for pancreatic cancer.

Topics: Animals; Apoptosis; Bridged Bicyclo Compounds, Heterocyclic; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Cell Proliferation; CREB-Binding Protein; Female; G1 Phase Cell Cycle Checkpoints; Gene Expression; Humans; Mice; Mice, Nude; Pancreatic Neoplasms; Pyrimidinones; Random Allocation; Tissue Array Analysis; Xenograft Model Antitumor Assays

Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations and epidermal growth factor receptor (EGFR) family signaling are drivers of tumorigenesis in pancreatic ductal adenocarcinoma (PDAC). Previous studies have demonstrated that combinatorial treatment of PDAC xenografts with the mitogen-activated protein kinase-extracellular-signal-regulated kinase (ERK) kinase1/2 (MEK1/2) inhibitor trametinib and the dual EGFR/human epidermal growth factor receptor 2 (HER2) inhibitor lapatinib provided more effective inhibition than either treatment alone. In this study, we have used the therapeutic antibodies, panitumumab (specific for EGFR) and trastuzumab (specific for HER2), to probe the role of EGFR and HER2 signaling in the proliferation of patient-derived xenograft (PDX) tumors. We show that dual anti-EGFR and anti-HER2 therapy significantly augmented the growth inhibitory effects of the MEK1/2 inhibitor trametinib in three different PDX tumors. While significant growth inhibition was observed in both KRAS mutant xenograft groups receiving trametinib and dual antibody therapy (tumors 366 and 608), tumor regression was observed in the KRAS wild-type xenografts (tumor 738) treated in the same manner. Dual antibody therapy in conjunction with trametinib was equally or more effective at inhibiting tumor growth and with lower apparent toxicity than trametinib plus lapatinib. Together, these studies provide further support for a role for EGFR and HER2 in pancreatic cancer proliferation and underscore the importance of therapeutic intervention in both the KRAS-rapidly accelerated fibrosarcoma kinase (RAF)-MEK-ERK and EGFR-HER2 pathways to achieve maximal therapeutic efficacy in patients.

Topics: Animals; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antineoplastic Agents; Carcinoma, Pancreatic Ductal; Cell Line, Tumor; Disease Models, Animal; Drug Therapy, Combination; ErbB Receptors; Humans; Male; Mitogen-Activated Protein Kinases; Mutation; Pancreatic Neoplasms; Panitumumab; Phosphorylation; Protein Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Pyridones; Pyrimidinones; Receptor, ErbB-2; Signal Transduction; Trastuzumab; Tumor Burden; Xenograft Model Antitumor Assays

Mutations of the oncogene KRAS are important drivers of pancreatic cancer progression. Activation of epidermal growth factor receptor (EGFR) and human EGFR2 (HER2) is observed frequent in pancreatic adenocarcinomas. Because of co-activation of these two signaling pathways, we assessed the efficacy of inhibition of EGFR/HER2 receptors and the downstream KRAS effector, mitogen-activated protein kinase/extracellular-signal regulated kinase (ERK) kinase 1 and 2 (MEK1/2), on pancreatic cancer proliferation in vitro and in a murine orthotopic xenograft model. Treatment of established and patient-derived pancreatic cancer cell lines with the MEK1/2 inhibitor trametinib (GSK1120212) inhibited proliferation, and addition of the EGFR/HER2 inhibitor lapatinib enhanced the inhibition elicited by trametinib in three of eight cell lines. Importantly, in the orthotopic xenograft model, treatment with lapatinib and trametinib resulted in significantly enhanced inhibition of tumor growth relative to trametinib treatment alone in four of five patient-derived tumors tested and was, in all cases, significantly more effective in reducing the size of established tumors than treatment with lapatinib or trametinib alone. Acute treatment of established tumors with trametinib resulted in an increase in AKT2 phosphorylation that was blunted in mice treated with both trametinib and lapatinib. These data indicate that inhibition of the EGFR family receptor signaling may contribute to the effectiveness of MEK1/2 inhibition of tumor growth possibly through the inhibition of feedback activation of receptor tyrosine kinases in response to inhibition of the RAS-RAF-MEK-ERK pathway. These studies provide a rationale for assessing the co-inhibition of these pathways in the treatment of pancreatic cancer patients.

Topics: Animals; Antineoplastic Agents; Cell Line, Tumor; ErbB Receptors; Humans; Lapatinib; MAP Kinase Kinase Kinases; MAP Kinase Signaling System; Mice; Neoplasm Transplantation; Pancreatic Neoplasms; Phosphorylation; Protein Kinase Inhibitors; Pyridones; Pyrimidinones; Quinazolines; Receptor, ErbB-2; Signal Transduction

Several lines of evidence indicate that Sirt1, a class III histone deacetylase (HDAC) is implicated in the initiation and progression of malignancies and thus gained attraction as druggable target. Since data on the role of Sirt1 in pancreatic ductal adenocarcinoma (PDAC) are sparse, we investigated the expression profile and prognostic significance of Sirt1 in vivo as well as cellular effects of Sirt1 inhibition in vitro.. Sirt1 expression was analyzed by immunohistochemistry in a large cohort of PDACs and correlated with clinicopathological and survival data. Furthermore, we investigated the impact of overexpression and small molecule inhibition on Sirt1 in pancreatic cancer cell culture models including combinatorial treatment with chemotherapy and EGFR-inhibition. Cellular events were measured quantitatively in real time and corroborated by conventional readouts including FACS analysis and MTT assays.. We detected nuclear Sirt1 expression in 36 (27.9%) of 129 PDACs. SIRT1 expression was significantly higher in poorly differentiated carcinomas. Strong SIRT1 expression was a significant predictor of poor survival both in univariate (p = 0.002) and multivariate (HR 1.65, p = 0.045) analysis. Accordingly, overexpression of Sirt1 led to increased cell viability, while small molecule inhibition led to a growth arrest in pancreatic cancer cells and impaired cell survival. This effect was even more pronounced in combinatorial regimens with gefitinib, but not in combination with gemcitabine.. Sirt1 is an independent prognosticator in PDACs and plays an important role in pancreatic cancer cell growth, which can be levered out by small molecule inhibition. Our data warrant further studies on SIRT1 as a novel chemotherapeutic target in PDAC.

Topics: Aged; Aged, 80 and over; Carcinoma, Pancreatic Ductal; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Cell Survival; Follow-Up Studies; Gefitinib; Gene Expression Regulation, Neoplastic; Humans; Middle Aged; Naphthalenes; Neoplasm Grading; Neoplasm Metastasis; Neoplasm Staging; Niacinamide; Pancreatic Neoplasms; Prognosis; Pyrimidinones; Quinazolines; Sirtuin 1

Pancreatic adenocarcinoma has repetitively proved refractory to chemotherapy and biologic compounds with only a few drugs offering limited benefit. A number of novel regimens has been tested in phase I trials and reported recently in the 2011 American Society of Clinical Oncology (ASCO) Gastrointestinal Cancers Symposium. Specifically, a novel mitogen-activated protein kinase kinase (MEK) inhibitor, a connective tissue growth factor inhibitor, a coagulase factor VIIa inhibitor, as well as adenovirus delivery of herpes simplex virus thymidine synthase gene followed by anti-herpetic treatment have all proven to be safe in pancreatic cancer patients. Phase II trials will provide further evidence whether they can become clinically relevant in the future.

Topics: Adenocarcinoma; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Anticoagulants; Antineoplastic Combined Chemotherapy Protocols; Clinical Trials, Phase I as Topic; Connective Tissue Growth Factor; Deoxycytidine; Enzyme Inhibitors; Factor VIIa; Gemcitabine; Humans; MAP Kinase Kinase 1; MAP Kinase Kinase 2; Pancreatic Neoplasms; Pyridones; Pyrimidinones; Treatment Outcome

Investigate the efficacy and pharmacodynamic effects of MK-1775, a potent Wee1 inhibitor, in both monotherapy and in combination with gemcitabine (GEM) using a panel of p53-deficient and p53 wild-type human pancreatic cancer xenografts.. Nine individual patient-derived pancreatic cancer xenografts (6 with p53-deficient and 3 with p53 wild-type status) from the PancXenoBank collection at Johns Hopkins were treated with MK-1775, GEM, or GEM followed 24 hour later by MK-1775, for 4 weeks. Tumor growth rate/regressions were calculated on day 28. Target modulation was assessed by Western blotting and immunohistochemistry.. MK-1775 treatment led to the inhibition of Wee1 kinase and reduced inhibitory phosphorylation of its substrate Cdc2. MK-1775, when dosed with GEM, abrogated the checkpoint arrest to promote mitotic entry and facilitated tumor cell death as compared to control and GEM-treated tumors. MK-1775 monotherapy did not induce tumor regressions. However, the combination of GEM with MK-1775 produced robust antitumor activity and remarkably enhanced tumor regression response (4.01-fold) compared to GEM treatment in p53-deficient tumors. Tumor regrowth curves plotted after the drug treatment period suggest that the effect of the combination therapy is longer-lasting than that of GEM. None of the agents produced tumor regressions in p53 wild-type xenografts.. These results indicate that MK-1775 selectively synergizes with GEM to achieve tumor regressions, selectively in p53-deficient pancreatic cancer xenografts.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Pancreatic Ductal; Cell Cycle Proteins; Cell Line, Tumor; Deoxycytidine; Disease Progression; Drug Synergism; Female; Gemcitabine; Genes, p53; Humans; Mice; Mice, Nude; Mutation; Neoplasms; Nuclear Proteins; Pancreatic Neoplasms; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Pyrazoles; Pyrimidines; Pyrimidinones; Tumor Burden; Xenograft Model Antitumor Assays

TRPM8 is a member of the melastatin-type transient receptor potential ion channel family. Activation by cold or by agonists (menthol, icilin) induces a transient rise in intracellular free calcium concentration ([Ca(2+)](i)). Our previous study demonstrated that Ca(2+)-permeable cation channels play a role in IGF-1-induced secretion of chromogranin A in human neuroendocrine tumor (NET) cell line BON [Mergler et al.: Neuroendocrinology 2006;82:87-102]. Here, we extend our earlier study by investigating the expression of TRPM8 and characterizing its impact on [Ca(2+)](i) and the secretion of neurotensin (NT). We identified TRPM8 expression in NET BON cells by RT-PCR, Western blotting and immunofluorescence staining. Icilin increased [Ca(2+)](i) in TRPM8-transfected human embryonic kidney cells (HEK293) but not in mock-transfected cells. Icilin and menthol induced Ca(2+) transients in BON cells as well as in primary NET cell cultures of two different pancreatic NETs as detected by single cell fluorescence imaging. Icilin increased non-selective cation channel currents in BON cells as detected by patch-clamp recordings. This activation was associated with increased NT secretion. Taken together, this study demonstrates for the first time the expression TRPM8 in NET cells and its role in regulating [Ca(2+)](i) and NT secretion. The regulation of NT secretion in NETs by TRPM8 may have a potential clinical implication in diagnosis or therapy.

Topics: Calcium; Humans; Membrane Potentials; Menthol; Models, Biological; Neuroendocrine Tumors; Neurotensin; Pancreatic Neoplasms; Pyrimidinones; TRPM Cation Channels; Tumor Cells, Cultured