OBJECTIVES: Oxaliplatin (OXA) and 5-fluorouracil (5-FU) are 2 commonly used chemotherapeutic agents for colorectal cancer (CRC). MicroRNAs (miRNAs, miRs) play crucial roles in the development of chemoresistance in various cancers. However, the role and mechanism of miR-224-5p in regulating CRC chemoresistance remain unclear. This study aims to investigate the function of miR-224-5p in chemoresistant CRC cells and the underlying mechanisms. METHODS: CRC datasets GSE28702 and GSE69657 were downloaded from the Gene Expression Omnibus (GEO) database. Differentially expressed miRNAs between drug-sensitive and resistant groups (OXA or 5-FU) were analyzed, and miR-224-5p was identified as the target miRNA. Chemoresistant cell lines HCT15-OXR, HCT15-5-FU, SW480-OXR, and SW480-5-FU were established. Transient transfections were performed using miR-224-5p mimics, inhibitors, and their respective negative controls (control mimic, control inhibitor) in these cell lines. Cells were treated with different concentrations of OXA or 5-FU post-transfection, and the half-maximal inhibitory concentration (IC₅₀) was determined using the cell counting kit-8 (CCK-8) assay. Cell proliferation was assessed by CCK-8 and colony formation assays. The expression levels of miR-224-5p, LC3, and P62 were measured by real-time polymerase chain reaction (real-time PCR) and/or Western blotting. Autophagic flux was assessed using a tandem fluorescent-tagged LC3 reporter assay. TargetScan 8.0, miRTarBase, miRPathDB, and HADb were used to predict B-cell lymphoma-2 (Bcl-2) as a potential miR-244-5p target, which was further validated by dual-luciferase reporter assays. RESULTS: Chemoresistant CRC cells exhibited down-regulated miR-224-5p expression, whereas up-regulation of miR-224-5p enhanced chemotherapy sensitivity. Exposure to OXA or 5-FU significantly increased autophagic activity in chemoresistant CRC cells, which was reversed by miR-224-5p overexpression. Dual-luciferase assays verified Bcl-2 as a direct target of miR-224-5p. CONCLUSIONS MiR-224-5p regulates chemoresistance in CRC by modulating autophagy through direct targeting of Bcl-2.
Humans ; MicroRNAs/physiology* ; Colorectal Neoplasms/drug therapy* ; Drug Resistance, Neoplasm/genetics* ; Autophagy/drug effects* ; Fluorouracil/pharmacology* ; Oxaliplatin ; Cell Line, Tumor ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Gene Expression Regulation, Neoplastic

This study explored the generation site and regulation mechanism of reactive oxygen species(ROS) in the apoptosis of colorectal cancer cells induced by furanodienone(Fur). RKO cells were treated with 200 μmol·L~(-1) of Fur, and the changes in intracellular nicotinamide adenine dinucleotide phosphate oxidase(NOX) activity were detected by the NOX activity detection method. The control group, Fur group, diphenyleneiodonium(DPI) inhibitor group for general NOX, mitochondrial-targeted antioxidant(MitoTEMPO) group, Fur+DPI group, Fur+MitoTEMPO group, and H_2O_2 positive control group were set up. Intracellular ROS levels were detected by the ROS fluorescent staining method, and NOX1-NOX5 protein expressions were detected by Western blot. The NOX1-specific inhibitor ML171 and NOX4-specific inhibitor(GLX351322) were further introduced, and the cell activity was determined by cell counting kit-8(CCK-8) assay. The effects of ROS level change on the protein expressions of NOX4 and peroxiredoxin 1(PRDX1) were measured by Western blot. BAY11-7082, which is an inhibitor of the inhibitor of nuclear factor κB protein α(IκBα), was used to explore the effect of the expression of phosphorylated nuclear factor κB(p-NF-κB) in the nucleus after the Fur treatment on the NOX4 protein level. The lentiviral plasmid and empty plasmid for PRDX1 gene silencing were constructed to transfect RKO cells, and stably transfected strains were screened. The impact of PRDX1 gene knockout on Fur-induced apoptosis was further analyzed using the flow cytometry assay. The findings demonstrate a considerable increase in mitochondrial ROS level in response to Fur treatment, with an increase in intracellular NOX activity. However, the mitochondrial ROS level is significantly reduced in the Fur+DPI group. The results from Western blot and CCK-8 analysis suggest that intracellular NOX1 and NOX4 protein expressions are elevated by Fur treatment, and GLX351322 effectively reverses the pro-apoptotic effect of Fur, while ML171 has a minimal impact on apoptosis rate. Meanwhile, Fur significantly boosts the level of p-NF-κB in the nucleus, whereas the protein levels of p-NF-κB and NOX4 are reduced after the BAY treatment. The regulation of Fur on NOX4 and PRDX1 protein expressions is negatively correlated. In the stably transfected cell strain with PRDX1 gene knockout, the apoptosis rate is considerably higher than that of the negative control group after Fur treatment. The above results indicate that Fur can induce the apoptosis of colorectal cancer cells by promoting the signal transduction of NF-κB in the nucleus and increasing the generation of mitochondrial ROS derived from NOX4 to inhibit the PRDX1 protein expression.
Humans ; Peroxiredoxins/metabolism* ; Apoptosis/drug effects* ; Reactive Oxygen Species/metabolism* ; NADPH Oxidase 4/metabolism* ; Mitochondria/genetics* ; Cell Line, Tumor ; Colorectal Neoplasms/drug therapy* ; NADPH Oxidases/metabolism* ; Furans/pharmacology*

This study aims to investigate the effect and mechanism of the herb pair Agrimoniae Herba-Coptidis Rhizoma in inhibiting angiogenesis in the colorectal cancer inflammatory microenvironment by using the method of network pharmacology and the zebrafish model. The method of network pharmacology was employed to obtain the active components, potential core targets, and signaling pathways regulated by the herb pair in inhibiting angiogenesis in the inflammatory microenvironment of colorectal cancer, on the basis of which the underlying mechanism was predicted. The zebrafish model of colorectal cancer was established, and the inflammatory microenvironment was modeled. The effects of different concentrations of the herb pair on the area, number, and length of intersegmental vessels(ISVs) of the zebrafish model were observed. Western blot and real-time quantitative PCR were employed to measure the protein and mRNA levels, respectively, of vascular endothelial growth factor A(VEGFA), vascular epidermal growth factor receptor 2(VEGFR2, also known as kdrl, Flk1), and vascular epidermal growth factor receptor 3(VEGFR3, also known as Flt4). A total of 18 active components and 488 potential targets of Agrimoniae Herba-Coptidis Rhizoma were predicted, and 108 common targets were shared by the herb pair and the disease. According to the results of KEGG pathway enrichment analysis, the angiogenesis-related factors VEGFA, kdrl, and Flt4 in the VEGFA/VEGFR2 signaling pathway were selected for verification. The zebrafish experiment showed that compared with the blank group, the model group showed increased area, number, and length of ISVs in the inflammatory microenvironment. Compared with the model group, the herb pair decreased the area, number, and length of ISVs in a concentration-dependent manner. Compared with the blank group, the model group showed up-regulated protein and mRNA levels of VEGFA, kdrl, and Flt4 in the inflammatory microenvironment. Compared with the model group, the herb pair down-regulated the protein and mRNA levels of VEGFA, kdrl, and Flt4 in a concentration-dependent manner. The results indicated that in the colorectal cancer inflammatory microenvironment, the herb pair Agrimoniae Herba-Coptidis Rhizoma could inhibit angiogenesis via multiple components, targets, and pathways. The anti-angiogenesis effect might be related to the down-regulation of the expression levels of angiogenesis-related factors VEGFA, kdrl, and Flt4 in the VEGFA/VEGFR2 signaling pathway.
Zebrafish ; Animals ; Drugs, Chinese Herbal/pharmacology* ; Network Pharmacology ; Colorectal Neoplasms/metabolism* ; Neovascularization, Pathologic/drug therapy* ; Humans ; Vascular Endothelial Growth Factor A/metabolism* ; Tumor Microenvironment/drug effects* ; Angiogenesis Inhibitors/pharmacology* ; Vascular Endothelial Growth Factor Receptor-2/metabolism* ; Signal Transduction/drug effects* ; Coptis chinensis ; Inflammation/drug therapy* ; Angiogenesis

In recent years, the clinical treatment of colorectal cancer(CRC) has made great progress, but chemoresistance is still one of the main reasons for reducing the survival rate of patients with colorectal cancer. Therefore, ameliorating chemotherapy resis-tance is an urgent problem to be solved. The purpose of this study was to investigate the regulatory role and related molecular mechanisms of hydroxysafflor yellow A(HSYA) in colorectal cancer cell proliferation, migration, and 5-fluorouracil(5-FU) chemoresistance. In this study, HCT116 and HT-29 cells were used as research subjects. Firstly, methyl thiazolyl tetrazolium(MTT) assay and colony formation assay were used to detect and analyze the effect of HSYA on the proliferation of CRC cells. Secondly, the effect of HSYA on the cell cycle in CRC cells was analyzed by cell cycle assay. Furthermore, the effect of HSYA on the migration of CRC cells was analyzed by wound-healing assay and Transwell assay. Based on the above, the influences of HSYA on 5-FU chemoresistance of CRC cells and related molecular mechanisms were explored and analyzed. The results showed that HSYA significantly inhibited the proliferation and migration of CRC cells, and arrested the cell cycle in G_0/G_1 phase. In addition, HSYA significantly ameliorated the chemoresistance of CRC cells to 5-FU. The results of acridine orange staining and Western blot showed that the autophagy activity of CRC cells in the HSYA and 5-FU combined treatment group was significantly higher than that in the 5-FU single drug treatment group. As compared with the 5-FU single drug treatment group, the phosphorylation levels of protein kinase B(Akt) and mammalian target of rapamycin(mTOR) in the HSYA and 5-FU combined treatment group were significantly reduced, indicating that the Akt/mTOR signaling pathway in the combined treatment group was down-regulated in CRC cells. In conclusion, HSYA may upregulate autophagy activity through the Akt/mTOR signaling pathway, thereby inhibiting the proliferation and migration of CRC cells and ameliorating the chemoresistance to 5-FU.
Humans ; Proto-Oncogene Proteins c-akt/metabolism* ; Drug Resistance, Neoplasm ; Cell Line, Tumor ; TOR Serine-Threonine Kinases/metabolism* ; Fluorouracil/pharmacology* ; Cell Proliferation ; Autophagy ; Colorectal Neoplasms/drug therapy*

OBJECTIVE: To investigate the effects of ethanol extract of Patrinia scabiosaefolia (EEPS) on chemo-resistance of colorectal cancer cells (CRC) and explore the possible molecular mechanisms. METHODS: 5-fluorouracil (5-FU)-resistant human colorectal carcinoma cell line (HCT-8/5-FU) and its parental cells HCT-8 were treated with EEPS (0, 0.25, 0.50, 1 or 2 mg/mL), or 5-FU (0, 100, 200, 400, 800 or 1600 μmol/L). The 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay was performed to evaluate the cell viability. Cell density was observed by phase-contrast microscope, cell counting and colony formation assay were used to determine the cell proliferation of HCT-8/5-FU cells treated with 0, 0.5, 1 or 2 mg/mL EEPS. Cell apoptosis was determined by Hoechst staining. Western-blot was performed to detect the phosphorylation of AKT as well as the protein expression level of B-cell CLL/lymphoma 2 (Bcl-2) and Bcl-2-associated X protein (Bax). RESULTS: Compared with HCT-8 cells, MTT assay results indicated that HCT-8/5-FU cells were resistant to 5-FU treatment (P<0.05), and sensitive to EEPS treatment (P>0.05). Moreover, compared with untreated HCT-8/5-FU cells, 1 and 2 mg/mL of EEPS treatment significantly reduced cell density, cell number, inhibited cell survival (P<0.05), and induced apoptosis in HCT-8/5-FU cells. Furthermore, 1 and 2 mg/mL of EEPS significantly decreased the phosphorylation level of p-AKT and Bcl-2 protein expression, and increased the expression of Bax protein (P<0.05). CONCLUSION EEPS is a promising therapeutic agent that may overcome chemo-resistance in cancer cells, likely through suppression of the AKT pathway and promotion of cancer cell apoptosis.
Apoptosis ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cell Survival ; drug effects ; Colorectal Neoplasms ; drug therapy ; pathology ; Drug Resistance, Neoplasm ; drug effects ; Fluorouracil ; pharmacology ; therapeutic use ; Humans ; Patrinia ; chemistry ; Phosphorylation ; drug effects ; Proto-Oncogene Proteins c-akt ; metabolism ; Signal Transduction ; drug effects ; Tumor Stem Cell Assay ; bcl-2-Associated X Protein ; metabolism

OBJECTIVE: To explore the association between expression of ADAM17 and cetuximad resistance in human colorectal cancer SW480 cells. METHODS: The expression of ADAM17 was detected using Western blotting in different human colorectal cancer cell lines, and the cells highly expressing ADAM17 were selected as the target cells. SW480 cells were transfected with ADAM17-siRNA 1 and ADAM17-siRNA 2 and the changes in the expression of ADAM17 protein were detected using Western blotting. SW480 cells were exposed to cetuximad for 24 h and the cell apoptosis was analyzed using flow cytometry. Transwell assay was used to examine the migration ability of SW480 cells with different expression levels of ADAM17; Western blotting was used to analyze the changes in the expressions of AKT signaling pathway-related proteins in the treated cells. RESULTS: The baseline expressions of ADAM17 were significantly higher in SW480 cells than in the other human colorectal cancer cell lines tested ( < 0.05). Both ADAM17-siRNA 1 and 2 effectively reduced the expression of ADAM17 protein in SW480 cells. Knockdown of ADAM17 with siRNA 1 significantly increased the sensitivity of SW480 cells to tocetuximad ( < 0.05), obviously inhibited the cell proliferation, migration and invasion, and significantly reduced the expressions of p-EGFR and p-AKT in the cells ( < 0.001). CONCLUSIONS ADAM17 knockdown obviously inhibits EGFR-AKT signaling pathway and increases the sensitivity of SW480 cells to tocetuximad.
ADAM17 Protein ; genetics ; metabolism ; Antineoplastic Agents, Immunological ; pharmacology ; Apoptosis ; Cell Line, Tumor ; Cell Movement ; Cell Proliferation ; Cetuximab ; pharmacology ; Colorectal Neoplasms ; drug therapy ; genetics ; metabolism ; pathology ; Drug Resistance, Neoplasm ; genetics ; ErbB Receptors ; metabolism ; Gene Knockdown Techniques ; Humans ; Neoplasm Invasiveness ; Oncogene Protein v-akt ; metabolism ; RNA, Small Interfering ; Signal Transduction ; Transfection ; methods

Considering the great potential of natural products as anticancer agents, the present study was designed to explore the molecular mechanisms responsible for anticancer activities of Mesua ferrea stem bark extract against human colorectal carcinoma. Based on MTT assay results, bioactive sub-fraction (SF-3) was selected for further studies using HCT 116 cells. Repeated column chromatography resulted in isolation of less active α-amyrin from SF-3, which was identified and characterized by GC-MS and HPLC methods. α-amyrin and betulinic acid contents of SF-3 were measured by HPLC methods. Fluorescent assays revealed characteristic apoptotic features, including cell shrinkage, nuclear condensation, and marked decrease in mitochondrial membrane potential in SF-3 treated cells. In addition, increased levels of caspases-9 and -3/7 levels were also observed in SF-3 treated cells. SF-3 showed promising antimetastatic properties in multiple in vitro assays. Multi-pathway analysis revealed significant down-regulation of WNT, HIF-1α, and EGFR with simultaneous up-regulation of p53, Myc/Max, and TGF-β signalling pathways in SF-3 treated cells. In addition, promising growth inhibitory effects were observed in SF-3 treated HCT 116 tumour spheroids, which give a hint about in vivo antitumor efficacy of SF-3 phytoconstituents. In conclusion, these results demonstrated that anticancer effects of SF-3 towards colon cancer are through modulation of multiple molecular pathways.
Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Cell Line, Tumor ; Colorectal Neoplasms ; drug therapy ; metabolism ; pathology ; physiopathology ; ErbB Receptors ; genetics ; metabolism ; HCT116 Cells ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit ; genetics ; metabolism ; Magnoliopsida ; chemistry ; Neoplasm Metastasis ; prevention & control ; Plant Bark ; chemistry ; Plant Extracts ; pharmacology ; Signal Transduction ; drug effects ; Wnt Proteins ; genetics ; metabolism

Cancer stem cells (CSCs) have tumor initiation, self-renewal, metastasis and chemo-resistance properties in various tumors including colorectal cancer. Targeting of CSCs may be essential to prevent relapse of tumors after chemotherapy. Phosphatidylinositol-3-kinase (PI3K) and mammalian target of rapamycin (mTOR) signals are central regulators of cell growth, proliferation, differentiation, and apoptosis. These pathways are related to colorectal tumorigenesis. This study focused on PI3K and mTOR pathways by inhibition which initiate differentiation of SW620 derived CSCs and investigated its effect on tumor progression. By using rapamycin, LY294002, and NVP-BEZ235, respectively, PI3K and mTOR signals were blocked independently or dually in colorectal CSCs. Colorectal CSCs gained their differentiation property and lost their stemness properties most significantly in dual-blocked CSCs. After treated with anti-cancer drug (paclitaxel) on the differentiated CSCs cell viability, self-renewal ability and differentiation status were analyzed. As a result dual-blocking group has most enhanced sensitivity for anti-cancer drug. Xenograft tumorigenesis assay by using immunodeficiency mice also shows that dual-inhibited group more effectively increased drug sensitivity and suppressed tumor growth compared to single-inhibited groups. Therefore it could have potent anti-cancer effects that dual-blocking of PI3K and mTOR induces differentiation and improves chemotherapeutic effects on SW620 human colorectal CSCs.
AC133 Antigen/genetics/metabolism ; Animals ; Antineoplastic Agents/pharmacology/therapeutic use ; Cell Differentiation/*drug effects ; Cell Line, Tumor ; Cell Survival/drug effects ; Chromones/pharmacology/therapeutic use ; Colorectal Neoplasms/drug therapy/metabolism/pathology ; Humans ; Imidazoles/pharmacology/therapeutic use ; Male ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Morpholines/pharmacology/therapeutic use ; Neoplastic Stem Cells/cytology/drug effects/metabolism ; Paclitaxel/pharmacology/therapeutic use ; Phosphatidylinositol 3-Kinases/*antagonists & inhibitors/metabolism ; Quinolines/pharmacology/therapeutic use ; SOXB1 Transcription Factors/genetics/metabolism ; Signal Transduction/*drug effects ; Sirolimus/pharmacology/therapeutic use ; TOR Serine-Threonine Kinases/*antagonists & inhibitors/metabolism ; Xenograft Model Antitumor Assays

The aim of the present study was to accurately evaluate the association of Sox2 expression with the survival of patients with digestive tract cancers. Relevant literatures were identified by comprehensively searching databases including the Pubmed, Embase, CBMdisc, and Wanfang (up to October 2014). A meta-analysis was performed to clarify the association between Sox2 expression and overall survival or clinicopathological parameters of patients with digestive tract cancers (esophageal, gastric, and colorectal cancers). The results showed a significant association between high Sox2 expression and poor overall survival in patients with digestive tract carcinomas (HR=1.55, 95% CI=1.04-2.31), especially for patients with esophageal cancer (HR=2.04, 95%CI=1.30-3.22), colorectal cancer (HR=1.40, 95% CI=1.04-1.89), and digestive tract adenocarcinoma (HR=1.80, 95% CI=1.12-2.89), for Europeans (HR=1.98, 95% CI=1.44-2.71) or patients who did not receive neoadjuvant treatment (HR=1.73, 95% CI=1.10-2.72). Furthermore, Sox2 over-expression was highly correlated with vascular invasion (OR=1.86, 95% CI=1.25-2.77) and poor differentiation (OR=1.88, 95% CI=1.14-3.08), especially in esophageal and colorectal cancers. In conclusion, Sox2 expression may serve as a novel prognostic factor for patients with digestive tract cancers. Over-expression of Sox2 that is correlated with vascular invasion and poor differentiation suggests poor outcomes of patients with digestive tract cancers.
Antineoplastic Agents ; therapeutic use ; Biomarkers, Tumor ; genetics ; metabolism ; Colorectal Neoplasms ; diagnosis ; drug therapy ; mortality ; pathology ; Esophageal Neoplasms ; diagnosis ; drug therapy ; mortality ; pathology ; Gastrointestinal Tract ; metabolism ; pathology ; Gene Expression ; Humans ; Neoadjuvant Therapy ; methods ; Neoplasm Grading ; Neoplasms, Vascular Tissue ; diagnosis ; drug therapy ; mortality ; secondary ; Prognosis ; SOXB1 Transcription Factors ; genetics ; metabolism ; Stomach Neoplasms ; diagnosis ; drug therapy ; mortality ; pathology ; Survival Analysis

Granulocyte colony-stimulating factor (G-CSF) is an essential regulator of neutrophil trafficking and is highly expressed in multiple tumors. Myeloid derived suppressor cells (MDSCs) promote neoplastic progression through multiple mechanisms by immune suppression. Despite the findings of G-CSF function in colon cancer progression, the precise mechanism of G-CSF on MDSCs regulation and its blockade effects on tumor growth remains a worthy area of investigation. In this study we observed an overexpression of G-CSF in a mouse colitis-associated cancer (CAC) model, which was consistent with the accumulation of MDSCs in mouse colon tissues. Further in vitro studies demonstrated that G-CSF could promote MDSCs survival and activation through signal transducer and activator of transcription 3 (STAT3) signaling pathway. Moreover, compared with isotype control, anti-G-CSF mAb treatment demonstrated reduced MDSC accumulation, which led to a marked decrease in neoplasm size and number in mice. Our results indicated that G-CSF is a critical regulating molecule in the migration, proliferation and function maintenance of MDSCs, which could be a potential therapeutic target for colitis-associated cancer.
Animals ; Carcinogenesis ; Colitis ; complications ; Colorectal Neoplasms ; complications ; drug therapy ; immunology ; metabolism ; Female ; Gene Expression Regulation, Neoplastic ; Granulocyte Colony-Stimulating Factor ; genetics ; metabolism ; Immunotherapy ; Mice ; Molecular Targeted Therapy ; Myeloid Cells ; immunology ; metabolism ; pathology