phenanthrenes has been researched along with Colonic-Neoplasms* in 37 studies
37 other study(ies) available for phenanthrenes and Colonic-Neoplasms
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Triptolide decreases tumor-associated macrophages infiltration and M2 polarization to remodel colon cancer immune microenvironment via inhibiting tumor-derived CXCL12.
Colon cancer is a common and deadly human digestive tract malignant tumor with poor prognosis. Immunotherapy has elicited tremendous success as a treatment modality for multiple solid tumors. Triptolide is extracted from the traditional Chinese medicine Tripterygium wilfordii Hook. F which shows various pharmacological actions including antitumor, anti-inflammatory, antimicrobial, antifibrosis, and antirheumatic. However, the influence of triptolide treatment on remodeling tumor immune microenvironment is still unknown in colon cancer. This study was aimed to investigate the therapeutic effect of triptolide treatment on colon cancer and the impact on tumor immune microenvironment and its underlying mechanism. We used CT26 subcutaneous tumors to conduct in vivo experiments and HT29, CT16, and Raw264.7 cells to perform in vitro assays. Triptolide had a therapeutic effect against colon cancer in vivo. Triptolide treatment distinctly inhibited the proliferation of colon cancer cells and induced apoptosis in vitro. In colon cancer immune microenvironment, triptolide treatment decreased the infiltration of tumor-associated macrophages through downregulating tumor-derived CXCL12 expression via nuclear factor kappa B and extracellular signal-regulated protein kinases 1 and 2 axis to remodel the immune microenvironment. Triptolide-educated colon cancers retarded the macrophages polarize to anti-inflammatory M2 status by decreasing the expression of Arg-1, CD206, and interleukin-10. Moreover, triptolide inhibited the migration of colon cancer cells via decreasing vascular endothelial growth factor expression. Our results identified the role of triptolide treatment in remodeling colon cancer immune microenvironment along with the distinct cytotoxicity function against colon cancer cells, which may provide the evidence for triptolide treatment in clinical. Topics: Animals; Apoptosis; Cell Line; Cell Line, Tumor; Cell Proliferation; Chemokine CXCL12; Colonic Neoplasms; Diterpenes; Down-Regulation; Epoxy Compounds; HT29 Cells; Humans; Male; Mice; Mice, Inbred BALB C; NF-kappa B; Phenanthrenes; RAW 264.7 Cells; Tumor Microenvironment; Tumor-Associated Macrophages | 2021 |
Cryptotanshinone alleviates chemotherapy-induced colitis in mice with colon cancer via regulating fecal-bacteria-related lipid metabolism.
Patients with colorectal cancer treated with 5-fluorouracil (5-FU) and irinotecan (CPT-11) exhibit a risk for chemotherapy-induced colitis (CIC) that may lead to fatal consequences. Cryptotanshinone (CTS) is a natural compound extracted from the root of Salvia miltiorrhiza Bunge that shows potent antitumor activities. We previously reported CTS relieved 5-FU/ CPT-11 induced colitis in tumor-free mice. In this study, we studied the effect of CTS on 5-FU/ CPT-11 induced colitis in mice with colitis associated colon cancer (CAC). The effects of CTS on CIC were evaluated by disease activity index (DAI) and histological assessment via hematoxylin-and-eosin staining. Serum lipids and lipid-metabolic enzymes were detected by commercial kits. Fecal microbial diversity was detected by 16S ribosomal RNA gene sequencing. To find the role of fecal bacteria in CAC mice with 5-FU/ CPT-11 induced colitis, pseudo-germ-free mice were established by intragastric administration of mixed antibiotics. Except for decreasing tumor number (3 ± 1 vs 6 ± 1, p < 0.05), CTS significantly alleviated DAI (1.9 ± 0.6 vs 2.6 ± 0.5, p < 0.05) and regulated serum lipids in CAC mice with 5-FU/ CPT-11induced colitis. Compared with model group, CTS significantly increased serum triglycerides (TG) (1.13 ± 0.26 mM vs 0.79 ± 0.03 mM, p < 0.05), high density lipoprotein (HDL) (3.88 ± 0.1 mM vs 3.28 ± 0.05 mM, p < 0.001) and oxidized low-density lipoprotein (oxLDL) (288.12 ± 65.92 ng/mL vs 150.72 ± 42.13 ng/mL, p < 0.05) level but decreased serum adiponectin level (1177.47 ± 179.2 pg/mL vs 1523.43 ± 91.8 pg/mL, p < 0.05). Among fecal bacteria significantly correlated with lipid metabolism, CTS significantly decreased the abundance of g__norank_f__Muribaculaceae (21.15 % ± 5.7 % vs 41.84 ± 12.0 %, p < 0.01) but increased that of g_Lactobacillus (11.13 % ± 6.6 % vs 5.7 % ± 4.6 %, p < 0.05), g__Alistipes (3.66 % ± 0.7 % vs 1.47 % ± 1,0%, p < 0.01) and g__Odoribacter (1.31 % ± 0.7 % vs 0.30 % ± 0.2 %, p < 0.01). In addition, the development of CIC and abnormal lipid metabolism were significantly prevented in pseudo-germ-free mice. Therefore, we concluded CTS alleviated 5FU/CPT-11 induced colitis in CAC mice via regulating fecal flora associated lipid metabolism. Topics: Animals; Anti-Inflammatory Agents; Antineoplastic Agents; Bacteria; Colitis; Colon; Colonic Neoplasms; Feces; Fluorouracil; Gastrointestinal Microbiome; Irinotecan; Lipid Metabolism; Male; Mice, Inbred BALB C; Phenanthrenes; RNA, Ribosomal, 16S | 2021 |
Diterpenoid anthraquinones as chemopreventive agents altered microRNA and transcriptome expressions in cancer cells.
Cryptotanshinone (CPT) and dihydrotanshinone (DHT) are diterpenoid anthraquinone compounds extracted from traditional Chinese herbal medicine (TCM). Recent studies have shown that CPT regulates the signal transduction pathways via microRNA (miRNA) alterations. However, few studies have investigated the role of DHT in miRNA alterations affecting cell-signaling pathways. This study aimed to investigate the miRNA alterations and post-transcriptional regulation activities of DHT in comparison to CPT.. HepG2 and HT-29 cells were treated with DHT or CPT for 72 h. MiRNA, transcription factor encoding mRNA, and downstream gene expression were determined using real-time quantitative PCR. Protein expression was analyzed using western blotting.. The results revealed that CPT and DHT targeted cell proliferation and apoptosis signaling pathways via miR-15a-5p, miR-27a-5p, miR-100-5p, and miR-200a-5p alterations.In silico target predictions showed that downregulation of epidermal growth factor receptor (EGFR) mRNA expression by DHT might also suppress the expression of STAT family proteins and lead to anti-proliferation effects. We also found that, compared to CPT, DHT might possess higher potency in cell growth regulation via multi-miRNA and transcription factor alterations.. This study revealed that CPT and DHT targeted cell proliferation and apoptosis signaling pathways via alterations in miRNAs and transcription factors. In addition, the findings of this study suggest that DHT is more potent than CPT in cancer chemopreventive activities. Therefore, DHT at a low dose is a TCM compound with less toxic side effects and may contribute to the development of natural medicine as a potential cancer chemopreventive agent. Topics: Anticarcinogenic Agents; Antineoplastic Agents, Phytogenic; Apoptosis; Apoptosis Regulatory Proteins; Cell Cycle Proteins; Cell Proliferation; Colonic Neoplasms; Furans; Gene Expression Regulation, Neoplastic; Gene Regulatory Networks; Hep G2 Cells; HT29 Cells; Humans; Liver Neoplasms; MicroRNAs; Phenanthrenes; Quinones; Signal Transduction; Transcription Factors; Transcriptome | 2021 |
A Triptolide Loaded HER2-Targeted Nano-Drug Delivery System Significantly Suppressed the Proliferation of HER2-Positive and BRAF Mutant Colon Cancer.
Colon cancer (CRC) was a malignant tumor and there were about 25% of patients with tumor metastasis at diagnosis stage. Chemotherapeutic agents for metastatic CRC patients were with great side effects and the clinical treatment results of advanced CRC were still not satisfactory. Human epidermal growth factor receptor 2 (HER2) is overexpressed in some CRC patients and is an effective target for CRC patient treatment. Anti-HER2 therapy had a beneficial role in the treatment of HER2-positive metastatic CRC with fewer side effects. CRC patients with BRAF mutations were resistant to HER2 antibodies treatment. Therefore, there was an urgent need to develop new therapeutic agents.. HER2 targeted nanoparticles (TPLNP) drug delivery system loading triptolide (TPL) were prepared and identified. The effects of TPLNP and free TPL on cell viability, targeting and cell cycle progression on HT29 (BRAF mutation) with HER2 overexpression, were evaluated by Cell Counting Kit-8 (CCK8), Fluorescence Activating Cell Sorter (FACS) and immunofluorescence methods, respectively. The anti-tumor efficacies of TPLNP were evaluated in subcutaneous xenograft model of colon cancer and the survival rate, tumor volume, liver and kidney indexes of tumor-bearing mice were measured.. TPLNP was small in nanosize (73.4±5.2nm) with narrow size distribution (PDI=0.15±0.02) and favorable zeta potential (pH=9.6, zeta potential: -57.3±6.69mV; pH=7.0, zeta potential: -28.7±5.1mV; pH=5.6, zeta potential: -21.1±4.73mV). Comparing with free TPL treatment group, TPLNP developed stranger colon cancer-killing efficiency in a dose- and time-dependent manner detected with CCK8 method; achieved good in vitro colon cancer targeting detected with flow cytometry and immunofluorescence experiments; enhanced more HT29-HER2 apoptosis and induced more cell cycle arrested in G1-S phase detected with FACS in vitro. As for in vivo antitumor response, TPLNP remarkably inhibited the growth of colon cancer in the colon cancer xenograft model, significantly improved the survival rate and did not exhibit significant liver and kidney toxicity in contrast with free TPL in vivo.. TPLNP was effectively against colon cancer with HER2 overexpression and BRAF mutation in pre-clinical models. In summary, the TPLNP appeared to be a promising treatment option for CRC in clinical application based on improved efficacy and the favorable safety profile. Topics: Animals; Antineoplastic Agents; Apoptosis; Carcinogenesis; Cell Cycle; Cell Death; Cell Proliferation; Cell Survival; Colonic Neoplasms; Diterpenes; Drug Delivery Systems; Epoxy Compounds; Female; HT29 Cells; Humans; Inhibitory Concentration 50; Kidney; Liver; Mice; Mice, Inbred BALB C; Mice, Nude; Mutation; Nanomedicine; Nanoparticles; Phenanthrenes; Proto-Oncogene Proteins B-raf; Receptor, ErbB-2; Signal Transduction | 2021 |
Combination of metronomic administration and target delivery strategies to improve the anti-angiogenic and anti-tumor effects of triptolide.
The metronomic administration of a low-dose cytotoxic agent with no prolonged drug-free breaks is an anti-angiogenic cancer treatment method. The use of nano-formulations in this manner enhances anti-tumor efficacy and reduces toxicity by inhibiting angiogenic activity, reduces adverse effects, and changes the biodistribution of TP in the body, steering TP away from potentially endangering healthy tissues. The present study uses liposomes and Asn-Gly-Arg (NGR) peptide conjugated aminopeptidase N(APN)-targeted liposomes for triptolide (TP), as a model for the investigation of targeted metronomic administration and subsequent effects on the toxicity profile and efficacy of the chemotherapeutic agent. Metronomic NGR-PEG-TP-LPs have been found to have enhanced anti-tumor activity, a phenomenon that is attributed to an increase in angiogenic inhibition properties. In vitro experiments demonstrate that the viability, migration, and tube formation of human umbilical vein endothelial cells (HUVECs) are obviously suppressed in comparison with that of other treatment groups. In vivo experiments also demonstrate that the anti-tumor efficacy of targeted metronomic administration is superior to that of liposome-administered treatments given at maximum tolerated dose (MTD) schemes, as is evidenced by markedly decreased tumor volume, vessel density, and the volume of circulating endothelial progenitor cells (CEPCs) in serum. Moreover, we observed that the metronomic administration of NGR-PEG-TP-LPs could elevate thrombospondin-1 (TSP-1) expression in tumors, a finding that is consistent with the promotion of TSP-1 secretion specifically from HUVECs. Additionally, metronomic NGR-PEG-TP-LPs have minimal drug-associated toxicity (weight loss, hepatotoxicity and nephrotoxicity in mice). Our research demonstrates the significance of targeted metronomic administration using liposomes for anti-angiogenic cancer therapy. Topics: Administration, Metronomic; Angiogenesis Inhibitors; Animals; Antineoplastic Agents; Cell Proliferation; Cell Survival; Colonic Neoplasms; Diterpenes; Drug Compounding; Epoxy Compounds; HCT116 Cells; Human Umbilical Vein Endothelial Cells; Humans; Liposomes; Mice; Oligopeptides; Phenanthrenes; Tissue Distribution; Treatment Outcome; Xenograft Model Antitumor Assays | 2020 |
Antitumor properties of triptolide: phenotype regulation of macrophage differentiation.
Tumor-associated macrophages (TAMs), which generally exhibit an M2-like phenotype, play a critical role in tumor development. Triptolide exerts a unique bioactive spectrum of anticancer activities. The aim of this study was to determine whether triptolide has any effect on the activation of TAMs and the production of tumor-promoting mediators. ICR-1 mice with azoxymethane/dextran sulfate sodium (AOM/DSS)-induced colon tumors and BALB/c mice co-inoculated with 4T1 cells and M2-polarized RAW264.7 cells were used to examine whether the inhibitory effect of triptolide on tumor progression was mediated by the targeting of TAMs. Real-time PCR, Western blot, immunofluorescence staining, and flow cytometry assays were performed to determine the expression of cell surface markers and cytokine production. The results showed that triptolide inhibited macrophage differentiation toward the M2 phenotype and abolished M2 macrophage-mediated tumor progression. Furthermore, triptolide inhibited the expression of M2 markers, such as CD206, Arginase 1, and CD204, and inhibited the secretion of anti-inflammatory cytokines. Thus our study indicated that triptolide selectively inhibited the functions of M2-polarized macrophages and TAMs, and this inhibitory effect of triptolide on TAM viability, differentiation, and cytokine production might elucidate the major mechanisms underlying its antitumor activity. Our findings provide important information for the potential clinical application of triptolide in cancer therapy. Topics: Animals; Antineoplastic Agents, Alkylating; Apoptosis; Breast Neoplasms; Cell Differentiation; Cell Proliferation; Colonic Neoplasms; Diterpenes; Epoxy Compounds; Female; Humans; Mice; Mice, Inbred BALB C; Mice, Inbred ICR; Mice, Nude; Phenanthrenes; Phenotype; Tumor Cells, Cultured; Tumor Microenvironment; Tumor-Associated Macrophages; Xenograft Model Antitumor Assays | 2020 |
Cryptotanshinone prevents muscle wasting in CT26-induced cancer cachexia through inhibiting STAT3 signaling pathway.
Salvia miltiorrhiza bunge (Danshen) has been extensively used to treat a wide variety of diseases including cancers. Cryptotanshinone is a major lipophilic compound extracted from the root of Danshen and has been reported to exert various pharmacological effects, however, its anti-cachectic remains unknown.. The present study aims to investigate the anti-cachectic efficacy of cryptotanshinone and elucidate the underlying mechanism.. Prevention of muscle wasting by cryptotanshinone in colon adenocarcinoma CT26-induced cachexia and CT26 conditioned medium (TCM)-induced myotubes were investigated. Main features of cancer cachexia were determined after cryptotanshinone administration. The therapeutic effect of cryptotanshinone on myotube atrophy was assessed by morphological observation and myotube fiber width determination. E3 ubiquitin ligases muscle RING-finger containing protein 1 (MuRF1) and muscle atrophy Fbox protein (MAFbx/Atrogin-1) expression and STAT3 activation were examined using western blot, real-time qPCR and dual-luciferase reporter gene assays both in vitro and in vivo. The myotubes were infected with lentiviruses expressing STAT3 or GFP.. In CT26 tumor-bearing mice, cryptotanshinone (20 and 60 mg/kg) administration drastically prevented systemic cancer cachexia from whole body weight loss and wasting of multiple tissues including heart, fat and skeletal muscle, with a negligible effect on cancer growth at dose of 20 mg/kg cryptotanshinone administration prevented the induction of MuRF1 and MAFbx/Atrogin-1 in cachectic muscles. Moreover, cryptotanshinone (2.5-10 μM) dose-dependently reduced the elevated expression of MuRF1 and MAFbx/Atrogin-1 in C2C12 myotubes, and improved myotube atrophy. We showed that cryptotanshinone significantly suppressed the hyper-activated STAT3 in cachectic muscles and C2C12 myotubes and inhibited STAT3 transcriptional activity, but it did not repress the activation of STAT1. The inhibitory effect of cryptotanshinone on TCM-induced myotube atrophy was blocked by STAT3 overexpression.. These data suggest that cryptotanshinone prevents muscle wasting in cancer cachexia through STAT3 inhibition, and it may be a promising candidate drug for the treatment of cancer cachexia. Topics: Adenocarcinoma; Animals; Cachexia; Colonic Neoplasms; HEK293 Cells; HeLa Cells; Humans; Male; Mice, Inbred BALB C; Muscle Fibers, Skeletal; Muscle Proteins; Muscular Atrophy; Phenanthrenes; Phosphorylation; Signal Transduction; SKP Cullin F-Box Protein Ligases; STAT3 Transcription Factor; Tripartite Motif Proteins; Ubiquitin-Protein Ligases; Weight Loss | 2020 |
Cryptotanshinone-Induced p53-Dependent Sensitization of Colon Cancer Cells to Apoptotic Drive by Regulation of Calpain and Calcium Homeostasis.
Over-expression of calpains in tumor tissues can be associated with cancer progression. Thus, inhibition of calpain activity using specific inhibitors has become a novel approach to control tumor growth. In this study, the anticancer potential of cryptotanshinone in combination with calpain inhibitor had been investigated in colon cancer cells and tumor xenograft. Cryptotanshinone elicited an initial endoplasmic reticular (ER) stress response, whereas prolonged stress would result in the promotion of apoptosis. It was then discovered that cryptotanshinone could cause rapid and sustained increase in cytosolic calcium in colon cancer cells accompanied by early GRP78 overexpression, which could be attenuated by pre-treatment of the calcium chelator BAPTA-AM. Cryptotanshinone also facilitated an early increase in calpain activity, which could be blocked by BAPTA-AM or the calpain inhibitor PD150606. A dynamic interaction between GRP78 and calpain during the action of cryptotanshinone was unveiled. This together with the altered NF-[Formula: see text]B signaling could be abolished by calpain inhibitor. GRP78 knockdown increased the sensitivity of cancer cells to cryptotanshinone-evoked apoptosis and reduction of cancer cell colony formation. Such sensitization of drug action had been confirmed to be p53-dependent by using p53-mutated (HT-29) and p53-deficient (HCT116 p53 Topics: Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Calcium; Calpain; Colonic Neoplasms; Endoplasmic Reticulum Chaperone BiP; Endoplasmic Reticulum Stress; Gene Expression; Heat-Shock Proteins; Homeostasis; Humans; Mice, Nude; Phenanthrenes; Phytotherapy; Tumor Cells, Cultured; Tumor Suppressor Protein p53 | 2020 |
RETRACTED: Triptolide inhibits the growth and migration of colon carcinoma cells by down-regulation of miR-191.
This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy).\ \ This article has been retracted at the request of the Editor-in-Chief.\ \ Concerns were raised about the background pattern of the Western Blots from Figure 2A. Given the comments of Dr Elisabeth Bik regarding this article “This paper belongs to a set of over 400 papers (as per February 2020) that share very similar Western blots with tadpole-like shaped bands, the same background pattern, and striking similarities in title structures, paper layout, bar graph design, and - in a subset - flow cytometry panels”, the journal requested the authors to provide the raw data. However, the authors were not able to fulfil this request and therefore the Editor-in-Chief decided to retract the article. Topics: Adenocarcinoma; Animals; Antineoplastic Agents, Alkylating; Cell Line, Tumor; Cell Movement; Cell Proliferation; Colonic Neoplasms; Diterpenes; Down-Regulation; Epoxy Compounds; Gene Expression Regulation, Neoplastic; Humans; Mice; MicroRNAs; Phenanthrenes; Xenograft Model Antitumor Assays | 2019 |
Metabolic reprogramming in colon cancer reversed by DHTS through regulating PTEN/AKT/HIF1α mediated signal pathway.
Metabolic reprogramming and hypoxia contribute to the resistance of conventional chemotherapeutic drugs in kinds of cancers. In this study, we investigated the effect of dihydrotanshinone I (DHTS) on reversing dysregulated metabolism of glucose and fatty acid in colon cancer and elucidated its mechanism of action.. Cell viability was determined by MTT assay. Oxidative phosphorylation, glycolysis, and mitochondrial fuel oxidation were assessed by Mito stress test, glycolysis stress test, and mito fuel flex test, respectively. Anti-cancer activity of DHTS in vivo was evaluated in Colon cancer xenograft. Hexokinase activity and free fatty acid (FFA) content were assessed using respective Commercial kits. Gene expression patterns were determined by performing DNA microarray analysis and real-time PCR. Protein expression was assessed using immunoblotting and immunohistochemistry.. DHTS showed similar cytotoxicity against colon cancer cells under hypoxia and normoxia. DHTS decreased the efficiency of glucose and FA as mitochondrial fuels in HCT116 cells, which efficiently reversed by VO-OHpic trihydrate. DHTS reduced hexokinase activity and free fatty acid (FFA) content in tumor tissue of xenograft model of colon cancer. Gene expression patterns in metabolic pathways were dramatically differential between model and treatment group. Increases in PTEN and a substantial decrease in the expression of SIRT3, HIF1α, p-AKT, HKII, p-MTOR, RHEB, and p-ACC were detected.. DHTS reversed metabolic reprogramming in colon cancer through PTEN/AKT/HIF1α-mediated signal pathway.. The study is the first to report the reverse of metabolic reprogramming by DHTS in colon cancer. Meantime, SIRT3/PTEN/AKT/HIF1α mediated signal pathway plays a critical role during this process. Topics: Animals; Apoptosis; Cell Proliferation; Colonic Neoplasms; Furans; Gene Expression Regulation, Neoplastic; Glycolysis; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Male; Mice; Mice, Nude; Mitochondria; Oxidative Phosphorylation; Phenanthrenes; Proto-Oncogene Proteins c-akt; PTEN Phosphohydrolase; Quinones; Signal Transduction; Tumor Cells, Cultured; Xenograft Model Antitumor Assays | 2018 |
Cryptotanshinone inhibits the growth and invasion of colon cancer by suppressing inflammation and tumor angiogenesis through modulating MMP/TIMP system, PI3K/Akt/mTOR signaling and HIF-1α nuclear translocation.
The aim of this study was to evaluate the pharmacological effects of CPT on CT26 colon cancer cells in vivo and in vitro, and to reveal the potential mechanism. CPT suppressed the proliferation and growth of CT26 colon cancer in vitro and in vivo. CPT inhibited the invasion of CT26 cells in vitro, and decreased the protein expressions of matrix metalloproteinase-2 (MMP-2) and MMP-9 but increased those of tissue inhibitor of metallopeptidase-1 (TIMP-1) and TIMP-2 in vitro and in vivo. It also inhibited tumor cell-induced angiogenesis of endothelial cells in vitro and rat aortic ring angiogenesis ex vivo, and possibly by suppressing angiogenesis-associated factors. CPT suppressed the expressions of inflammatory factors in vivo and in vitro. Mechanism studies showed that CPT inhibited the PI3K/AKT/mTOR signaling pathway, as evidenced by decreased expressions of phospho-PI3K (p-PI3K), p-Akt and p-mTOR. Moreover, CPT significantly suppressed the nuclear expression but increased the cytosolic expression of hypoxia inducible factor-1α (HIF-1α). Collectively, CPT inhibited the growth, invasion, inflammation and angiogenesis in CT26 colon cancer, and at least partly, by regulating the PI3K/Akt/mTOR signaling and the nuclear translocation of HIF-1α. Topics: Active Transport, Cell Nucleus; Anti-Inflammatory Agents; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; Drugs, Chinese Herbal; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Immunomodulation; Matrix Metalloproteinase 2; Matrix Metalloproteinase 9; Neoplasm Invasiveness; Neovascularization, Pathologic; Oncogene Protein v-akt; Phenanthrenes; Phosphatidylinositol 3-Kinases; Salvia miltiorrhiza; Signal Transduction; Tissue Inhibitor of Metalloproteinase-1; TOR Serine-Threonine Kinases | 2018 |
Cryptotanshinone induces ROS-dependent autophagy in multidrug-resistant colon cancer cells.
The development of novel chemotherapeutic agents is highly desired for colon cancer treatment, in particular for the multidrug-resistant cancer types. Cryptotanshinone (CTS), an active quinoid diterpene isolated from Salvia miltiorrhiza Bunge, was previously reported to induce autophagy in various colon cancer cell lines. However, its mechanisms of action have not been fully understood. The current study aims to explore the mechanisms by which CTS induces autophagy in a multidrug-resistant human colon cancer cell line SW620 Ad300. Using MTT assay, CTS at 10 μM exhibited no significant cytotoxicity on human normal colon fibroblasts CCD-18Co, but induced 45.67% and 48.35% cell death in SW620 and SW620 Ad300 cells, respectively. Further studies revealed that CTS induced weak apoptosis (9.37%) and significant caspase-independent cell death in SW620 Ad300 cells. In the same cell line, CTS also induced significant autophagy, which was found to promote cell death and to mediate the cytotoxicity of CTS in these multidrug-resistant cells. Moreover, activation of ROS-p38 MAPK-NF-κB signaling pathway was involved in autophagic cell death induced by CTS in SW620 Ad300 cells. Interestingly, our results also demonstrated a complementary relationship between CTS-induced apoptosis and autophagic cell death in SW620 Ad300 cells. Taken together, CTS induces autophagic cell death in SW620 Ad300 cells via the ROS-p38 MAPK-NF-κB signaling pathway, and it might be a potential candidate as a chemotherapeutic agent for the treatment of multidrug-resistant colon cancer. Topics: Autophagy; Cell Survival; Colonic Neoplasms; Dose-Response Relationship, Drug; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Humans; Phenanthrenes; Reactive Oxygen Species; Structure-Activity Relationship; Tumor Cells, Cultured | 2017 |
Danshen improves survival of patients with colon cancer and dihydroisotanshinone I inhibit the proliferation of colon cancer cells via apoptosis and skp2 signaling pathway.
Danshen (Salvia miltiorrhiza Bunge) is widely used in traditional Chinese medicine. However, it's definite clinical effect and mechanism on colon carcinoma is unclear.. To test the hypothesis that the protective effect of danshen on colon cancer and discover the bioactive compounds through in vitro study.. We conducted a nationwide cohort study by using population-based data from the Taiwan National Health Insurance Research Database (NHIRD). The study cohort comprised patients diagnosed with malignant neoplasm of colon (ICD-9-CM codes:153) in catastrophic illness database between January 1, 2000, and December 31, 2010. We used the Kaplan-Meier method to estimate colon [corrected] cancer cumulative incidences. Next, human colon cancer cells (HCT 116 cells and HT29 cells) were used to investigate the effect of dihydroisotanshinone I (DT) on the proliferation and apoptosis of human colon cancer cells and the underlying mechanism through XTT assay and flow cytometry. The in vivo effect of DT treatment was investigated through a xenograft nude mouse model.. In our study, the in vivo protective effect of danshen in the different stage of colon cancer patients was validated through data from the National Health Insurance Research Database in Taiwan. In vitro, we found that dihydroisotanshinone I (DT), a bioactive compound present in danshen, can inhibit the proliferation of colon carcinoma cells, HCT 116 cells and HT-29 cells. Moreover, DT induced apoptosis of colorectal cancer cells. DT also repressed the protein expression of Skp2 (S-Phase Kinase Associated Protein 2) and the mRNA levels of its related gene, Snail1 (Zinc finger protein SNAI1) and RhoA (Ras homolog gene family, member A). In addition, DT also blocked the colon cancer cells recruitment ability of macrophage by decreasing CCL2 secretion in macrophages. DT treatment also significantly inhibited the final tumor volume in a xenograft nude mouse model.. Danshen has protective effects in colon cancer patients, which could be attributed to DT through blocking the proliferation of colon cancer cells through apoptosis. Topics: Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Cell Movement; Cohort Studies; Colonic Neoplasms; HCT116 Cells; HT29 Cells; Humans; Mice; Neoplasms, Experimental; Phenanthrenes; RAW 264.7 Cells; RNA, Messenger; S-Phase Kinase-Associated Proteins; Salvia miltiorrhiza; Taiwan | 2017 |
Potentially reversible acute cerebellar toxicity associated with Minnelide.
Minnelide is an experimental antineoplastic agent that is currently the subject of a phase 1 clinical trial for the treatment of pancreatic and gastrointestinal malignancies. In this study, we documented two cases of reversible acute cerebellar toxicity (REACT) associated with Minnelide and compared its radiological manifestations with other cerebellotoxic agents.. Both patients had histories of progressive metastatic cancer and participated in a phase 1 clinical trial with Minnelide. They had an MRI examination including T2WI, FLAIR and SWI, axial and coronal DWI, and ADC map on admission and follow up.. In each patient, the initial MRI demonstrated increased signal on FLAIR and restricted diffusion in the cerebellar cortex without involvement of deep cerebellar nuclei or supratentorial areas. The presenting symptoms and the majority of imaging findings resolved on follow up MRI.. To our knowledge, Minnelide has shown an uncommon radiologic pattern of isolated cerebellar cortical involvement compared to other causes of cerebellar toxicity. Since this is a new medication, physicians' familiarity with the presenting symptoms and its temporal association with the imaging findings is important. Topics: Cerebellum; Clinical Trials, Phase I as Topic; Colonic Neoplasms; Diterpenes; Epoxy Compounds; Fatal Outcome; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Organophosphates; Pancreatic Neoplasms; Phenanthrenes | 2017 |
Miltirone induced mitochondrial dysfunction and ROS-dependent apoptosis in colon cancer cells.
To study the characteristics of miltirone-induced anti-colon cancer effects.. Cell viability was detected using MTT assay. LDH (lactate dehydrogenase) leakage was detected using CytoTox96® non-radioactive cytotoxicity kit. Apoptosis was detected by FCM (flow cytometry). Caspase activation was determined by chemiluminescence or western blotting. AIF (apoptosis-inducing factor) expression in the cell fraction was determined by western blotting. ROS (reactive oxygen species), MMP (mitochondrial membrane potential) and mitochondrial mass were determined by confocal microscope. Intracellular calcium was detected by both FCM and confocal microscope. To determine the roles of ROS and Ca(2+) in the pro-apoptotic activity of miltirone, colon cancer cells were pretreated with kinds of antioxidants, dicoumarol, calpeptin or BAPTA-AM in some cases.. Miltirone exhibited potent cytotoxicity on colon cancer cells with a better selectivity than that of dihydrotanshinone. The pro-apoptotic activity of miltirone was p53- and ROS-dependent. In detail, miltirone induced direct mitochondrial damage, including significant decrease of mitochondrial ROS, MMP, mass and increase of intracellular ROS and Ca(2+). NQO1 (quinone oxidoreductase1) was supposed to be a defender for the cytotoxicity induced by miltirone in colon cancer cells. Furthermore, miltirone induced time- and concentration-dependent translocation of AIF and activation of caspases.. In this study, ROS- and p53-dependent apoptosis induced by miltirone on colon cancer cells was firstly revealed. Strong positive feedback between mitochondrial dysfunction and accumulation of intracellular Ca(2+) was suggested to be the characteristic of the anti-colon cancer activity of miltirone. Topics: Apoptosis; Apoptosis Inducing Factor; Calcium; Caspases; Cell Line, Tumor; Cell Survival; Colonic Neoplasms; Dicumarol; Humans; L-Lactate Dehydrogenase; Membrane Potential, Mitochondrial; Mitochondria; NAD(P)H Dehydrogenase (Quinone); Phenanthrenes; Reactive Oxygen Species | 2016 |
Triptolide abrogates growth of colon cancer and induces cell cycle arrest by inhibiting transcriptional activation of E2F.
Despite significant progress in diagnostics and therapeutics, over 50 thousand patients die from colorectal cancer annually. Hence, there is urgent need for new lines of treatment. Triptolide, a natural compound isolated from the Chinese herb Tripterygium wilfordii, is effective against multiple cancers. We have synthesized a water soluble analog of triptolide, named Minnelide, which is currently in phase I trial against pancreatic cancer. The aims of the current study were to evaluate whether triptolide/Minnelide is effective against colorectal cancer and to elucidate the mechanism by which triptolide induces cell death in colorectal cancer. Efficacy of Minnelide was evaluated in subcutaneous xenograft and liver metastasis model of colorectal cancer. For mechanistic studies, colon cancer cell lines HCT116 and HT29 were treated with triptolide and the effect on viability, caspase activation, annexin positivity, lactate dehydrogenase release, and cell cycle progression was evaluated. Effect of triptolide on E2F transcriptional activity, mRNA levels of E2F-dependent genes, E2F1- retinoblastoma protein (Rb) binding, and proteins levels of regulator of G1-S transition was also measured. DNA binding of E2F1 was evaluated by chromatin immunoprecipitation assay. Triptolide decreased colon cancer cell viability in a dose- and time-dependent fashion. Minnelide markedly inhibited the growth of colon cancer in the xenograft and liver metastasis model of colon cancer and more than doubles the median survival of animals with liver metastases from colon cancer. Mechanistically, we demonstrate that at low concentrations triptolide induces apoptotic cell death but at higher concentrations it induces cell cycle arrest. Our data suggest that triptolide is able to induce G1 cell cycle arrest by inhibiting transcriptional activation of E2F1. Our data also show that triptolide downregulates E2F activity by potentially modulating events downstream of DNA binding. Therefore, we conclude that Triptolide and Minnelide are effective against colon cancer in multiple pre-clinical models. Topics: Animals; Antineoplastic Agents, Alkylating; Apoptosis; Cell Cycle Checkpoints; Cell Survival; Colonic Neoplasms; Diterpenes; E2F Transcription Factors; Epoxy Compounds; Female; HCT116 Cells; HT29 Cells; Humans; Mice, Nude; Organophosphates; Phenanthrenes; Xenograft Model Antitumor Assays | 2015 |
Sensitivity of apoptosis-resistant colon cancer cells to tanshinones is mediated by autophagic cell death and p53-independent cytotoxicity.
Multidrug resistance (MDR) develops in nearly all patients with colon cancer. The reversal of MDR plays an important role in the success of colon cancer chemotherapy. One of the commonest mechanisms conferring MDR is the suppression of apoptosis in cancer cells.. This study investigated the sensitivity of cryptotanshinone (CTS) and dihydrotanshinone (DTS), two lipophilic tanshinones from a traditional Chinese medicine Salvia miltiorrhiza, in apoptosis-resistant colon cancer cells.. Cell viability was measured by MTT assay. Cell cycle distribution and apoptosis were determined by flow cytometry. Protein levels were analyzed by western blot analysis. The formation of acidic vesicular organelles was visualized by acridine orange staining.. Experimental results showed that multidrug-resistant colon cancer cells SW620 Ad300 were sensitive to both CTS and DTS in terms of cell death, but with less induction of apoptosis when compared with the parental cells SW620, suggesting that other types of cell death such as autophagy could occur. Indeed, the two tanshinones induced more LC3B-II accumulation in SW620 Ad300 cells with increased autophagic flux. More importantly, cell viability was increased after autophagy inhibition, indicating that autophagy induced by the two tanshinones was pro-cell death. Besides, the cytotoxic actions of the two tanshinones were p53-independent, which could be useful in inhibiting the growth of apoptosis-resistant cancer cells with p53 defects.. The current findings strongly indicate that both CTS and DTS could inhibit the growth of apoptosis-resistant colon cancer cells through induction of autophagic cell death and p53-independent cytotoxicity. They are promising candidates to be further developed as therapeutic agents in the adjuvant therapy for colon cancer, especially for the apoptosis-resistant cancer types. Topics: Abietanes; Apoptosis; Autophagy; Cell Line, Tumor; Cell Survival; Colonic Neoplasms; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Drugs, Chinese Herbal; Humans; Phenanthrenes; Tumor Suppressor Protein p53 | 2015 |
Phosphonooxymethyl Prodrug of Triptolide: Synthesis, Physicochemical Characterization, and Efficacy in Human Colon Adenocarcinoma and Ovarian Cancer Xenografts.
A disodium phosphonooxymethyl prodrug of the antitumor agent triptolide was prepared from the natural product in three steps (39% yield) and displayed excellent aqueous solubility at pH 7.4 (61 mg/mL) compared to the natural product (17 μg/mL). The estimated shelf life (t90) for hydrolysis of the prodrug at 4 °C and pH 7.4 was found to be two years. In a mouse model of human colon adenocarcinoma (HT-29), the prodrug administered intraperitoneally was effective in reducing or eliminating xenograft tumors at dose levels as low as 0.3 mg/kg when given daily and at 0.9 mg/kg when given less frequently. When given via intraperitoneal and oral routes at daily doses of 0.6 and 0.9 mg/kg, the prodrug was also effective and well tolerated in a mouse model of human ovarian cancer (A2780). Topics: Adenocarcinoma; Animals; Antineoplastic Agents; Cell Line, Tumor; Colon; Colonic Neoplasms; Diterpenes; Drug Stability; Epoxy Compounds; Female; HT29 Cells; Humans; Mice; Mice, Nude; Organophosphates; Ovarian Neoplasms; Ovary; Phenanthrenes; Prodrugs; Solubility | 2015 |
Triptolide synergistically enhances antitumor activity of oxaliplatin in colon carcinoma in vitro and in vivo.
Triptolide (TPL) is a major active component isolated from the natural herb Tripteryglum wilfordii Hook. F. It has proved to possess a variety of pharmacological effects including anti-inflammatory and antitumor activities. The aim of the present study is to explore the efficiency of combination therapy with TPL and oxaliplatin (OXA) and identify the in vitro and in vivo cytotoxicity on colon cancer lines and mice model. Cell viability was measured by MTT assay and cell apoptosis rate was analyzed by FACS assay after treatment with TPL and OXA alone, and TPL combined with OXA in colon cancer cell line SW480. The results demonstrated that combination therapy of TPL and OXA could effectively inhibit the proliferation of colon cancer cell line SW480 and induce cell apoptosis of colon cancer cells. It was partly induced by inhibiting nuclear translocation of β-catenin and the expression of the target genes in cell cycle, which was detected by western blotting and real-time PCR. Moreover, in nude mice model, tumor growth was significantly suppressed in the group treated with TPL in combination with OXA. There was no obvious cytotoxity in mice analyzed by normal blood test and liver and kidney toxicity test. In conclusion, our result revealed that the combination therapy with TPL and OXA exerted synergistic antitumor effects at low concentration in colon cancer cells, with less cytotoxity, which exhibited high potency for clinical applications. Topics: Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; beta Catenin; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; Disease Models, Animal; Diterpenes; Drug Synergism; Epoxy Compounds; Flow Cytometry; Gene Expression Regulation, Neoplastic; Humans; Male; Mice; Molecular Structure; Organoplatinum Compounds; Oxaliplatin; Phenanthrenes; Protein Transport | 2014 |
6-Acetonyldihydrochelerythrine Is a Potent Inducer of Apoptosis in HCT116 and SW620 Colon Cancer Cells.
6-Acetonyldihydrochelerythrine (1), a benzophenanthridine alkaloid, isolated from the methanol extract of Zanthoxylum capense, displayed potent cytotoxic activity in human HCT116 and SW620 colon carcinoma cells, to a higher extent than 5-fluorouracil (5-FU), the cornerstone chemotherapeutic agent in colon cancer. Cytotoxicity of 1 was evaluated by MTS, lactate dehydrogenase (LDH), and Guava ViaCount assays. Interestingly, 1 significantly induced cytotoxicity in both cell lines, leading to a significant increase in LDH release, as compared to 5-FU. Further, Guava ViaCount flow cytometry assays demonstrated that 1 significantly increased cell death, as shown by the presence of a significantly higher population of apoptotic cells in both cell lines, as compared to cells exposed to 5-FU. Furthermore, evaluation of nuclear morphology by Hoechst staining of 1-treated HCT116 and SW620 cells confirmed flow cytometry results, demonstrating a marked induction of apoptotic cell death by 1, again to a further extent than that elicited by 5-FU. In addition, immunoblot analysis to ascertain the molecular events triggered by 1 exposure was performed. The results show that 1 exposure reduced the steady-state expression and activation of the pro-survival proteins ERK5 and Akt and increased the steady-state expression of p53 in both HCT116 and SW620 cells. Changes in ERK5 or Akt activation can be ascertained by evaluating the ratio of p-ERK5/ERK5 or p-Akt/Akt. In addition, exposure to 1 reduced expression of XIAP, Bcl-XL, and Bcl-2, while increasing the cleavage of poly(ADP-ribose) polymerase in both cell lines. Collectively, the data indicate that 6-acetonyldihydrochelerythrine (1) is a potent inducer of apoptosis in HCT116 and SW620 cell lines, highlighting its potential relevance in colon cancer. Topics: Alkaloids; Antineoplastic Agents; Apoptosis; Colon; Colonic Neoplasms; Drug Screening Assays, Antitumor; Fluorouracil; HCT116 Cells; Humans; Molecular Structure; Phenanthrenes; Poly(ADP-ribose) Polymerases; Zanthoxylum | 2014 |
Herbal compound triptolide synergistically enhanced antitumor activity of amino-terminal fragment of urokinase.
Urokinase (uPA) and its receptor (uPAR) play an important role in tumour growth and metastasis, and overexpression of these molecules is strongly correlated with poor prognosis in a variety of malignant tumours. Targeting the excessive activation of this system as well as the proliferation of the tumour vascular endothelial cell would be expected to prevent tumour neovasculature and halt tumour development. The amino terminal fragment (ATF) of urokinase has been confirmed effective to inhibit the proliferation, migration and invasiveness of cancer cells via interrupting the interaction of uPA and uPAR. Triptolide (TPL) is a purified diterpenoid isolated from the Chinese herb Tripterygium wilfordii Hook F that has shown antitumor activities in various cancer cell types. However, its therapeutic application is limited by its toxicity in normal tissues and complications caused in patients. In this study, we attempted to investigate the synergistic anticancer activity of TPL and ATF in various solid tumour cells.. Using in vitro and in vivo experiments, we investigated the combined effect of TPL and ATF at a low dosage on cell proliferation, cell apoptosis, cell cycle distribution, cell migration, signalling pathways, xenograft tumour growth and angiogenesis.. Our data showed that the sensitivity of a combined therapy using TPL and ATF was higher than that of TPL or ATF alone. Suppression of NF-κB transcriptional activity, activation of caspase-9/caspase-3, cell cycle arrest, and inhibition of uPAR-mediated signalling pathway contributed to the synergistic effects of this combination therapy. Furthermore, using a mouse xenograft model, we demonstrated that the combined treatment completely suppressed tumour growth by inhibiting angiogenesis as compared with ATF or TPL treatment alone.. Our study suggests that lower concentration of ATF and TPL used in combination may produce a synergistic anticancer efficacy that warrants further investigation for its potential clinical applications. Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Cycle Checkpoints; Cell Line, Tumor; Cell Movement; Cell Proliferation; Colonic Neoplasms; Diterpenes; Drug Synergism; Epoxy Compounds; HCT116 Cells; Human Umbilical Vein Endothelial Cells; Humans; Male; Mice; Peptides; Phenanthrenes; Signal Transduction; Tumor Burden; Urokinase-Type Plasminogen Activator; Xenograft Model Antitumor Assays | 2013 |
Dihydrotanshinone induces p53-independent but ROS-dependent apoptosis in colon cancer cells.
The therapeutic potential of various tanshinones was examined and compared for their anti-cancer activities on colon cancer cells. The role of ROS generation in the pro-apoptotic activity of dihydrotanshinone (DHTS) was further studied.. Cell viability was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis and poly-ADP-ribose-polymerase (PARP) cleavage were respectively measured by flow cytometer and Western blot. Changes of mitochondrial membrane potential (MMP), mitochondrial ROS (mitoROS) and total ROS were determined by confocal system under an inverted microscope.. Among the different tanshinones examined, DHTS produced the most potent anti-cancer effect. DHTS induced a selective cytotoxicity and apoptosis in both HCT116 p53(-/-) and HCT116 p53(+/+) colon cancer cells. A time- and concentration-dependent PARP cleavage further confirmed the apoptotic activity. In this regard, it was found DHTS provoked mitochondrial dysfunction in the early stage by decreasing MMP and mitoROS levels. This was followed by a time-dependent increase in intracellular ROS generation. Pretreatment with N-acetyl-l-cysteine (NAC) or catalase-PEG, the free radical scavengers, reduced apoptotic cell death. From these findings, it seems that leakage of ROS from mitochondria into cytosol by DHTS represents the major contributory factor leading to cell death in colon cancer cells.. We report for the first time that DHTS induces apoptosis in colon cancer cells through a p53-independent pathway. Disturbance of ROS generation at the oxidative phosphorylation (OXPHOS) complex in mitochondria followed by the decrease of MMP and increase of intracellular ROS accumulation are suggested to be involved in the pro-apoptotic activity of DHTS. Topics: Apoptosis; Blotting, Western; Caco-2 Cells; Cell Survival; Colonic Neoplasms; Flow Cytometry; Free Radical Scavengers; Furans; HCT116 Cells; Humans; Membrane Potential, Mitochondrial; Microscopy, Confocal; Oxidative Phosphorylation; Phenanthrenes; Poly(ADP-ribose) Polymerases; Quinones; Reactive Oxygen Species; Time Factors; Tumor Suppressor Protein p53 | 2013 |
Triptolide inhibits colon cancer cell proliferation and induces cleavage and translocation of 14-3-3 epsilon.
Triptolide is a diterpenoid triepoxide derived from the traditional Chinese medical herb Tripterygium wilfordii. In the present study, we demonstrated that this phytochemical attenuated colon cancer growth in vitro and in vivo. Using a proteomic approach, we found that 14-3-3 epsilon, a cell cycle- and apoptosis-related protein, was altered in colon cancer cells treated with triptolide. In this regard, triptolide induced cleavage and perinuclear translocation of 14-3-3 epsilon. Taken together, our findings suggest that triptolide may merit investigation as a potential therapeutic agent for colon cancer, and its anticancer action may be associated with alteration of 14-3-3 epsilon. Topics: 14-3-3 Proteins; Amino Acid Sequence; Animals; Antineoplastic Agents, Alkylating; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; Diterpenes; Electrophoresis, Gel, Two-Dimensional; Epoxy Compounds; Humans; Medicine, Chinese Traditional; Mice; Mice, Nude; Molecular Sequence Data; Phenanthrenes; Proteomics; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Transplantation, Heterologous; Tripterygium | 2012 |
Aristolactam-type alkaloids from Orophea enterocarpa and their cytotoxicities.
A new aristolactam, named enterocarpam-III (10-amino-2,3,4,6-tetramethoxy phenanthrene-1-carboxylic acid lactam, 1) together with the known alkaloid stigmalactam (2), were isolated from Orophea enterocarpa. Their structures were elucidated on the basis of interpretation of their spectroscopic data. Compounds 1 and 2 exhibited significant cytotoxicities against human colon adenocarcinoma (HCT15) cell line with IC(50) values of 1.68 and 1.32 μM, respectively. Topics: Adenocarcinoma; Annonaceae; Cell Line, Tumor; Cell Survival; Colonic Neoplasms; Drug Discovery; Humans; Indole Alkaloids; Lactams; Molecular Structure; Phenanthrenes; Plant Extracts | 2012 |
Inhibition of poly(ADP-ribose) polymerase down-regulates BRCA1 and RAD51 in a pathway mediated by E2F4 and p130.
Inhibitors of poly(ADP-ribose) polymerase (PARP) are in clinical trials for cancer therapy, on the basis of the role of PARP in recruitment of base excision repair (BER) factors to sites of DNA damage. Here we show that PARP inhibition to block BER is toxic to hypoxic cancer cells, in which homology-dependent repair (HDR) is known to be down-regulated. However, we also report the unexpected finding that disruption of PARP, itself, either via chemical PARP inhibitors or siRNAs targeted to PARP-1, can inhibit HDR by suppressing expression of BRCA1 and RAD51, key factors in HDR of DNA breaks. Mechanistically, PARP inhibition was found to cause increased occupancy of the BRCA1 and RAD51 promoters by repressive E2F4/p130 complexes, a pathway prevented by expression of HPV E7, which disrupts p130 activity, or by siRNAs to knock down p130 expression. Functionally, disruption of p130 by E7 expression or by siRNA knockdown also reverses the cytotoxicity and radiosensitivity associated with PARP inhibition, suggesting that the down-regulation of BRCA1 and RAD51 is central to these effects. Direct measurement of HDR using a GFP-based assay demonstrates reduced HDR in cells treated with PARP inhibitors. This work identifies a mechanism by which PARP regulates DNA repair and suggests new strategies for combination cancer therapies. Topics: Cell Line, Tumor; Colonic Neoplasms; Crk-Associated Substrate Protein; DNA Repair; Down-Regulation; E2F4 Transcription Factor; Enzyme Inhibitors; Genes, BRCA1; Humans; Phenanthrenes; Poly (ADP-Ribose) Polymerase-1; Poly(ADP-ribose) Polymerase Inhibitors; Poly(ADP-ribose) Polymerases; Promoter Regions, Genetic; Rad51 Recombinase; Radiation-Sensitizing Agents; RNA, Small Interfering | 2010 |
Triptolide downregulates Rac1 and the JAK/STAT3 pathway and inhibits colitis-related colon cancer progression.
Triptolide, a diterpenoid triepoxide from the traditional Chinese medicinal herb Tripterygium wilfordii Hook. f., is a potential treatment for autoimmune diseases as well a possible anti-tumor agent. It inhibits proliferation of colorectal cancer cells in vitro and in vivo. In this study, its ability to block progress of colitis to colon cancer, and its molecular mechanism of action are investigated. A mouse model for colitis-induced colorectal cancer was used to test the effect of triptolide on cancer progression. Treatment of mice with triptolide decreased the incidence of colon cancer formation, and increased survival rate. Moreover, triptolide decreased the incidence of tumors in nude mice inoculated with cultured colon cancer cells dose-dependently. In vitro, triptolide inhibited the proliferation, migration and colony formation of colon cancer cells. Secretion of IL6 and levels of JAK1, IL6R and phosphorylated STAT3 were all reduced by triptolide treatment. Triptolide prohibited Rac1 activity and blocked cyclin D1 and CDK4 expression, leading to G1 arrest. Triptolide interrupted the IL6R-JAK/STAT pathway that is crucial for cell proliferation, survival, and inflammation. This suggests that triptolide might be a candidate for prevention of colitis induced colon cancer because it reduces inflammation and prevents tumor formation and development. Topics: Animals; Cell Transformation, Neoplastic; Colitis; Colonic Neoplasms; Dextran Sulfate; Dimethylhydrazines; Diterpenes; Epoxy Compounds; Humans; Interleukin-6; Janus Kinases; Male; Mice; Mice, Inbred BALB C; Mice, Inbred ICR; Mice, Nude; Neoplasm Transplantation; Phenanthrenes; rac1 GTP-Binding Protein; Signal Transduction; STAT3 Transcription Factor; Tumor Burden | 2009 |
Inhibitory effects of tanshinone II-A on invasion and metastasis of human colon carcinoma cells.
To investigate the effects and possible mechanisms of tanshinone II-A, an alcohol extract of the root of Salvia miltiorrhiza Bunge, on tumor invasion and metastasis of human colon carcinoma (CRC) cells.. The effects of tanshinone II-A on invasion and metastasis of CRC cell lines HT29 and SW480 were evaluated by in vitro and in vivo assays. Western blotting was used to investigate possible molecular mechanisms of tanshinone II-A anti-cancer actions.. Tanshinone II-A inhibited migration and invasion of CRC cells in a dose-dependent manner. The inhibitory effect also depended on time, with the most significant effects observed at 72 h. Tanshinone II-A also significantly inhibited in vivo metastasis of colon carcinoma SW480 cells. It inhibited in vitro and in vivo invasion and metastasis of CRC cells by reducing levels of urokinase plasminogen activator (uPA) and matrix metalloproteinases (MMP)-2 and MMP-9, and by increasing levels of tissue inhibitor of matrix metalloproteinase protein (TIMP)-1 and TIMP-2. Tanshinone II-A was also shown to suppress the nuclear factor-kappaB (NF-kappaB) signal.. Tanshinone II-A inhibited in vitro and in vivo invasion and metastasis of CRC cells. The effect resulted from changes in the levels of uPA, MMP-2, MMP-9, TIMP-1 and TIMP-2, and apparent inhibition of the NF-kappaB signal transduction pathway. Topics: Abietanes; Animals; Antineoplastic Agents, Phytogenic; Cell Line, Tumor; Colonic Neoplasms; Colorectal Neoplasms; Dose-Response Relationship, Drug; HT29 Cells; Humans; Mice; Mice, Nude; Neoplasm Invasiveness; Neoplasm Metastasis; Phenanthrenes; Plant Extracts; Plant Roots; Salvia miltiorrhiza; Signal Transduction; Time Factors | 2009 |
Growth inhibition and apoptosis induction by tanshinone IIA in human colon adenocarcinoma cells.
Tanshinone IIA is the most abundant diterpene quinone in Danshen, Salviae miltiorrhizae Radix, a widely prescribed traditional herbal medicine that is used to treat cardiovascular and inflammatory diseases. Recently, tanshinone IIA was demonstrated to induce cell death and apoptosis in a variety of tumors. However, the effect of tanshinone IIA on human colon cancer cells is not clearly understood yet. In this study, the antigrowth and apoptosis-eliciting effects of tanshinone IIA, as well as its cellular mechanisms of actions, were investigated in Colo-205 human colon cancer cells. Tanshinone IIA reduced cell growth in a concentration-dependent manner, inducing apoptosis accompanied by an increase in TUNEL staining and by an increased percentage of cells in the sub-G1 fraction. The expression of p53 and p21 and mitochondrial cytochrome c release were increased in tanshinone IIA-treated cells. In addition, the expression of Fas proteins was up-regulated by tanshinone IIA. Tanshinone IIA-induced catalytic activation of caspases was confirmed by cleavage of caspase-8 and caspase-3. These findings suggest that tanshinone IIA induces apoptosis in Colo-205 cells through both mitochondrial-mediated intrinsic and Fas-mediated extrinsic caspase cell-death pathways. Accordingly, the chemotherapeutic potential of tanshinone IIA for colon cancer warrants further study. Topics: Abietanes; Adenocarcinoma; Animals; BALB 3T3 Cells; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; Humans; Mice; Phenanthrenes | 2008 |
Growth inhibition and apoptosis induction by tanshinone I in human colon cancer Colo 205 cells.
Tanshinone I (Tan-I) and tanshinone IIA (Tan-IIA) were isolated from Danshen (Salviae Miltiorrhizae Radix), a widely prescribed traditional herbal medicine that is used to treat cardiovascular and dysmenorrhea diseases. In our previous study, Tan-IIA was demonstrated to induce apoptosis in human colon cancer Colo 205 cells. However, the effect of Tan-I on human colon cancer cells is not clearly understood yet. In this study, the anti-growth and apoptosis-eliciting effects of Tan-I, as well as its cellular mechanisms of actions, were investigated in Colo 205 human colon cancer cells. Tan-I reduced cell growth in a concentration-dependent manner, inducing apoptosis accompanied by an increase in TUNEL staining and in cells in the sub-G1 fraction. The expression of p53, p21, bax and caspase-3 increased in Tan-I-treated cells. In addition, the cell cycle analysis showed G0/G1 arrest. These findings suggest that Tan-I induces apoptosis in Colo 205 cells through both mitochondrial-mediated intrinsic cell-death pathways and p21-mediated G0/G1cell cycle arrest. Accordingly, the therapeutic potential of Tan-I for colon cancer deserves further study. Topics: Abietanes; Antineoplastic Agents, Phytogenic; Apoptosis; bcl-2-Associated X Protein; Caspase 3; Cell Line, Tumor; Colonic Neoplasms; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; G1 Phase; Humans; Phenanthrenes; Resting Phase, Cell Cycle; Salvia miltiorrhiza; Tumor Suppressor Protein p53 | 2008 |
Tanshinone IIA down-regulates the protein expression of ErbB-2 and up-regulates TNF-alpha in colon cancer cells in vitro and in vivo.
Tanshinone IIA (Tan-IIA) was isolated from Salviae Miltiorrhizae Radix. Our previous studies showed that Tan-IIA induced apoptosis in human colon cancer colo 205 cells, but the molecular mechanisms of the effect of Tan-IIA on human colon cancer were not clearly elucidated. The protein expression of ErbB-2 was up-regulated and activated in human and experimental colon cancers. In the present study, the effects of Tan-IIA on the protein expression of ErbB-2 in colo 205 cells were investigated. In vitro, colo 205 cells were treated with various concentrations of Tan-IIA (1, 2 and 5 mug/ ml) for 24 h, and the protein expression of TNF-alpha, ErbB-2 and caspase-3 was assayed by Western blotting. For the in vivo studies, male SCID mice were xenografted with colo 205 cells, and from day 10, Tan IIA (20 mg/kg/day, dissolved in corn oil) was administered by oral feeding for 30 days. As a control, mice with xenografted tumors were separately treated with corn oil (0.1 ml/10 g body weight). Expression of TNF-alpha, ErbB-2 and caspase-3 proteins was measured by Western blot analysis. Our results showed that Tan-IIA down-regulated the protein expression of ErbB-2 and up-regulated TNF-alpha and caspase-3 in colo 205 cells in vitro. In a colo 205 xenograft model, treatment with Tan-IIA caused up-regulation of TNF-alpha, caspase-3 and down-regulation of ErbB-2 protein expression as compared to the controls. Based on these observations, one possible molecular mechanisms by which Tan-IIA inhibits the proliferation of colo 205 cells is through the down-regulation of ErbB-2 protein expression and the up-regulation of the protein expression of TNF-alpha and caspase-3. Topics: Abietanes; Actins; Animals; Antineoplastic Agents, Phytogenic; Caspase 3; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; Disease Models, Animal; Down-Regulation; Humans; Male; Mice; Mice, SCID; Neoplasm Transplantation; Phenanthrenes; Receptor, ErbB-2; Tumor Necrosis Factor-alpha; Up-Regulation | 2008 |
Herbal diterpenoids induce growth arrest and apoptosis in colon cancer cells with increased expression of the nonsteroidal anti-inflammatory drug-activated gene.
Novel chemotherapeutic agents derived from active phytochemicals could be used as adjuvants and improve the anti-carcinogenicity of standard drug treatments. However, their precise mechanisms of action are sometimes unclear. In this study, the anti-carcinogenic effect of the herbal diterpenoid pseudolaric acid B (PAB) on the growth and apoptosis of colon cancer cells was investigated, and to compare that with the more toxic compound triptolide. PAB induced growth inhibition and apoptosis in HT-29 cells, which were associated with cell cycle arrest at the G(2)/M phase, modulation of cyclin expression and downregulation of the protooncogene c-myc. In addition, PAB also inhibited bcl-x(L) expression, induced cleavage of procaspase-3 and its substrate poly(ADP-ribose) polymerase (PARP), which together caused DNA fragmentation and nuclear chromatin condensation. Concomitantly, the modulation of the growth-related and apoptotic factors by PAB was accompanied by the increased protein and gene expression of the nonsteroidal anti-inflammatory drug-activated gene (NAG-1), which occurred along with cyclooxygenase-2 inhibition. The effects of PAB on PARP cleavage and NAG-1 overexpression were not reversible upon removal of the drug from the culture medium. Similar cytotoxic and pro-apoptotic effects were also attained by treating the HT-29 cells with another diterpenoid triptolide, but its actions on cell cycle progression and on the upstream transcriptional regulation of NAG-1 both took place in a less coherent manner. These findings exemplify the potential of herbal terpenoids, particularly PAB, in modulating colon cancer carcinogenesis through known molecular targets and precise mechanism of action. Topics: Antineoplastic Agents, Phytogenic; Apoptosis; Cell Cycle; Cell Line, Tumor; Cell Nucleus; Cell Proliferation; Colonic Neoplasms; Cyclooxygenase 2; Cytokines; Diterpenes; DNA Fragmentation; Epoxy Compounds; Flow Cytometry; Fluorescent Dyes; Gene Expression Regulation, Neoplastic; Growth Differentiation Factor 15; HT29 Cells; Humans; Immunoblotting; Indoles; Phenanthrenes; Poly(ADP-ribose) Polymerase Inhibitors; PPAR gamma; Reverse Transcriptase Polymerase Chain Reaction; Tetrazolium Salts; Thiazoles | 2007 |
Triptolide inhibits cyclooxygenase-2 and inducible nitric oxide synthase expression in human colon cancer and leukemia cells.
Triptolide (TP), a traditional Chinese medicine, has been reported to be effective in the treatment of autoimmune diseases and exerting antineoplastic activity in several human tumor cell lines. This study investigates the antitumor effect of TP in human colon cancer cells (SW114) and myelocytic leukemia (K562), and elucidates the possible molecular mechanism involved. SW114 and K562 cells were treated with different doses of TP (0, 5, 10, 20, or 50 ng/ml). The cell viability was assessed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT). Results demonstrated that TP inhibited the proliferation of both tumor cell lines in a dose-dependent manner. To further investigate its mechanisms, the products prostaglandin E(2) (PGE(2)) and nitric oxide (NO) were measured by enzyme-linked immunosorbent assay (ELISA). Our data showed that TP strongly inhibited the production of NO and PGE(2). Consistent with these results, the expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) was up-regulated both at the mRNA level and the protein expression level, as shown by real-time RT-PCR and Western blotting. These results indicated that the inhibition of the inflammatory factor COX-2 and iNOS activity could be involved in the antitumor mechanisms of TP. Topics: Base Sequence; Cell Line, Tumor; Cell Survival; China; Colonic Neoplasms; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Diterpenes; DNA Primers; Epoxy Compounds; Humans; K562 Cells; Leukemia; Medicine, Chinese Traditional; Nitric Oxide Synthase Type II; Phenanthrenes; RNA, Messenger; Transcription, Genetic | 2007 |
Synergistic effect of triptolide combined with 5-fluorouracil on colon carcinoma.
To investigate the inhibitive effects of triptolide (TPL) combined with 5-fluorouracil (5-FU) on colon carcinoma HT-29 cells in vitro and in vivo and their side effects.. HT-29 cells were cultured with RPMI 1640 medium. The single or combined effects of TPL and 5-FU on HT-29 cells were examined by MTT assay, flow cytometry. The combined effects were evaluated by the median-effect principle. The model of tumour xenografts was established in nude mice. TPL 0.25 mg/kg/day and 5-FU 12 mg/kg/day, either in combination or on their own, were injected into mice and the inhibitive effects and side effects were observed.. TPL and 5-FU either combined or alone inhibited significantly the proliferation of HT-29 cells and induced obvious apoptosis. Mean (SD) growth inhibition rate reached 94.92 (2.76)% and the apoptic rate at 48 h reached 41.71 (1.38)%. The combined effects were synergistic (CI<1) at lower concentrations. TPL or 5-FU alone inhibited significantly the growth of tumour xenografts and the inhibition rates were 78.53% and 84.16%; the drugs combined had more significant effect, the tumour inhibition rate reaching 96.78%. During the course of chemotherapy, no obvious side effect was observed.. The combined effects of TPL and 5-FU on the growth of colon carcinoma in vitro and in vivo were superior to the effects when the agents were used individually. TPL combined with 5-FU had synergistic effects at lower concentrations and promoted apoptosis, but did not increase the side effects of chemotherapy. Topics: Animals; Anti-Inflammatory Agents, Non-Steroidal; Antimetabolites, Antineoplastic; Apoptosis; Carcinoma; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; Diterpenes; Drug Synergism; Epoxy Compounds; Fluorouracil; HT29 Cells; Humans; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasm Transplantation; Phenanthrenes; Plant Extracts; Tripterygium; Xenograft Model Antitumor Assays | 2007 |
Carnosol inhibits beta-catenin tyrosine phosphorylation and prevents adenoma formation in the C57BL/6J/Min/+ (Min/+) mouse.
Carnosol, a constituent of the herb, rosemary, has shown beneficial medicinal and antitumor effects. Using the C57BL/6J/Min/+ (Min/+) mouse, a model of colonic tumorigenesis, we found that dietary administration of 0.1% carnosol decreased intestinal tumor multiplicity by 46%. Previous studies showed that tumor formation in the Min/+ mouse was associated with alterations in the adherens junctions, including an increased expression of tyrosine-phosphorylated beta-catenin, dissociation of beta-catenin from E-cadherin, and strongly reduced amounts of E-cadherin located at lateral plasma membranes of histologically normal enterocytes. Here, we confirm these findings and show that treatment of Min/+ intestinal tissue with carnosol restored both E-cadherin and beta-catenin to these enterocyte membranes, yielding a phenotype similar to that of the Apc(+/+) wild-type (WT) littermate. Moreover, treatment of WT intestine with the phosphatase inhibitor, pervanadate, removed E-cadherin and beta-catenin from the lateral membranes of enterocytes, mimicking the appearance of the Min/+ tissue. Pretreatment of WT tissue with carnosol inhibited the pervanadate-inducible expression of tyrosine-phosphorylated beta-catenin. Thus, the Apc(Min) allele produces adhesion defects that involve up-regulated expression of tyrosine-phosphorylated proteins, including beta-catenin. Moreover, these data suggest that carnosol prevents Apc-associated intestinal tumorigenesis, potentially via its ability to enhance E-cadherin-mediated adhesion and suppress beta-catenin tyrosine phosphorylation. Topics: Abietanes; Adenoma; Animals; beta Catenin; Cadherins; Cell Adhesion; Cell Membrane; Colonic Neoplasms; Cytoskeletal Proteins; Enterocytes; Female; Intestine, Small; Mice; Mice, Inbred C57BL; Phenanthrenes; Phosphorylation; Rosmarinus; Trans-Activators; Tyrosine; Vanadates | 2005 |
Molecular mechanisms of denbinobin-induced anti-tumorigenesis effect in colon cancer cells.
To explore both the in vitro and in vivo effects of denbinobin against colon cancer cells and clarify its underlying signal pathways.. We used COLO 205 cancer cell lines and nude mice xenograft model to study the in vitro and in vivo anti-cancer effects of denbinobin.. Denbinobin at concentration of 10-20 micromol/L dose-dependently suppressed COLO 205 cell proliferation by MTT test. Flow cytometry analysis and DNA fragmentation assay revealed that 10-20 micromol/L denbinobin treatment induced COLO 205 cells apoptosis. Western blot analysis showed that caspases 3, 8, 9 and Bid protein were activated by denbinobin treatment to COLO 205 cells accompanied with cytochrome c and apoptosis-inducing factor (AIF) translocation. Pretreatment of MEK 1 inhibitor (U10126), but not p38 inhibitor (SB203580) and JNK inhibitor (SP600125), reversed denbinobin-induced caspase 8, 9 and Bid activation in COLO 205 cells suggesting that extracellular signal-regulated kinase were involved in the denbinobin-induced apoptosis in COLO 205 cells. Significant regression of tumor up to 68% was further demonstrated in vivo by treating nude mice bearing COLO 205 tumor xenografts with denbinobin 50 mg/kg intraperitoneally.. Our findings suggest that denbinobin could inhibit colon cancer growth both in vitro and in vivo. Activation of extrinsic and intrinsic apoptotic pathways and AIF were involved in the denbinobin-induced COLO 205 cell apoptosis. Topics: Animals; Anthraquinones; Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; Mice; Mice, Nude; Phenanthrenes; Transplantation, Heterologous | 2005 |
PG490-88, a derivative of triptolide, causes tumor regression and sensitizes tumors to chemotherapy.
Treatment of solid tumors with combinations of chemotherapeutic agents has not led to significant increases in long-term survival. Recent studies support a role for inhibitors of checkpoint arrest as a means to enhance the cytotoxicity of chemotherapy. We have shown previously that triptolide (PG490), an oxygenated diterpene derived from a Chinese medicinal plant, induces apoptosis in cultured tumor cells and sensitizes tumor cells to topoisomerase inhibitors by blocking p53-mediated induction of p21. Here we extend our studies to a tumor xenograft model and evaluate the efficacy and safety of PG490-88 (14-succinyl triptolide sodium salt), a water-soluble prodrug of PG490. We also look at the combination of PG490 or PG490-88 with CPT-11, a topoisomerase I inhibitor, in cultured cells and in the tumor xenograft model. We show that PG490-88 is a safe and potent antitumor agent when used alone, causing tumor regression of lung and colon tumor xenografts. We also show that PG490-88 acts in synergy with CPT-11 to cause tumor regression. A phase I trial of PG490-88 for solid tumors began recently and safety and optimal dosing data should accrue within the next 12 months. Our findings that PG490-88 causes tumor regression and that it acts in synergy with DNA-damaging chemotherapeutic agents suggest a role as an antineoplastic agent and chemosensitizer for the treatment of patients with solid tumors. Topics: Animals; Antineoplastic Agents; Camptothecin; Cell Cycle; Colonic Neoplasms; Cyclin-Dependent Kinase Inhibitor p21; Cyclins; Diterpenes; Drug Resistance, Neoplasm; Drug Synergism; Enzyme Inhibitors; Epoxy Compounds; Humans; Irinotecan; Lung Neoplasms; Mice; Mice, Nude; Phenanthrenes; Transplantation, Heterologous; Tumor Cells, Cultured; Tumor Suppressor Protein p53 | 2003 |
Cytotoxic activities of tanshinones against human carcinoma cell lines.
Fifteen tanshinone analogues isolated from the chloroform extract of Danshen roots (Salviae Miltiorrhizae Radix) by chromatographic procedures were tested for their cytotoxic activities against KB, Hela, Colo-205 and Hep-2 carcinoma cell lines. Several of them were effective at concentrations below 1 micrograms/ml concentrations. Tanshinone analogues with either hydroxy substitutions or olefinic feature in ring A demonstrated higher biologic activities. Analysis of structure-activity relationship indicate that the basic requirement for activity is the presence of a furano-o-naphthoquinone in the molecule. Compounds which lack an intact furan ring were found to be inactive. It is suggested that the planar phenanthrene ring of the tanshinones may be essential for interaction with DNA molecule whereas the furano-o-quinone moiety could be responsible for the production of reactive free radicals in the close vicinity of the bases to cause DNA damage. Topics: Abietanes; Anti-Infective Agents; Carcinoma; Colonic Neoplasms; Drug Screening Assays, Antitumor; HeLa Cells; Humans; KB Cells; Laryngeal Neoplasms; Lethal Dose 50; Phenanthrenes; Tumor Cells, Cultured | 1991 |