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Oxaliplatin (OXA) is the first-line chemotherapy drug for metastatic colorectal cancer (mCRC), and the emergence of drug resistance is a major clinical challenge. Although there have been numerous studies on OXA resistance, but its underlying molecular mechanisms are still unclear. This study aims to identify key regulatory genes and pathways associated with OXA resistance. The Gene Expression Omnibus (GEO) GSE42387 dataset containing gene expression profiles of parental and OXA-resistant LoVo cells was applied to explore potential targets. GEO2R, STRING, CytoNCA (a plug-in of Cytoscape), and DAVID were used to analyze differentially expressed genes (DEGs), protein–protein interactions (PPIs), hub genes in PPIs, and gene ontology (GO)/Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis. R2 online platform was used to run a survival analysis of validated hub genes enriched in KEGG pathways. The ENCORI database predicted microRNAs for candidate genes. A survival analysis of those genes was performed, and validated using the OncoLnc database. In addition, the 'clusterProfiler' package in R was used to perform gene set enrichment analysis (GSEA). We identified 395 DEGs, among which 155 were upregulated and 240 were downregulated. In total, 95 DEGs were screened as hub genes after constructing the PPI networks. Twelve GO terms and three KEGG pathways (steroid hormone biosynthesis, malaria, and pathways in cancer) were identified as being significant in the enrichment analysis of hub genes. Twenty-one hub genes enriched in KEGG pathways were defined as key genes. Among them AKT3, phospholipase C Beta 4 (PLCB4), and TGFB1 were identified as OXA-resistance genes through the survival analysis. High expressions of AKT3 and TGFB1 were each associated with a poor prognosis, and lower expression of PLCB4 was correlated with worse survival. Further, high levels of hsa-miR-1271-5p, which potentially targets PLCB4, were associated with poor overall survival in patients with CRC. Finally, we found that PLCB4 low expression was associated with MAPK signaling pathway and VEGF signaling pathway in CRC. Our results demonstrated that hsa-miR-1271-5p/PLCB4 in the pathway in cancer could be a new potential therapeutic target for mCRC with OXA resistance.

The prevalence rate of nonalcoholic fatty liver disease (NAFLD) has been reported in 74 to 90% of morbidly obese patients. This study aims to develop a scoring system that predicts significant liver fibrosis in morbidly obese patients. This prospective cohort study involved 123 morbidly obese patients who underwent metabolic surgery at Taipei Medical University Hospital between October 2016 and June 2018. Wedge liver biopsy was performed during surgery, and significant liver fibrosis was defined as a fibrosis score ≧ 2. Ultrasonography and transient elastography were performed prior to surgery to assess the risk factors associated with significant liver fibrosis. Mean patient age was 35.5 years, mean body mass index (BMI) was 40.6 kg/m2, and 87 (70.7%) were female. Fibrosis staging revealed 28 (22.8%) at stage 2, 14 (11.4%) at stage 3, and 2 (1.6%) at stage 4. Patients were then separated into training (n = 73) and validation (n = 50) cohorts. Multivariate analysis revealed a liver stiffness measurement (LSM) > 7 kPa and aspartate aminotransferase/platelet ratio index (APRI) > 0.40 as independent factors associated with significant liver fibrosis among the training cohort. Fibroscan-base score weighted sum of (1 for presence of APRI > 0.40) + (2 for presence of LSM > 7 kPa) yielded the highest area under receiver operating curve (0.854, P = 0.0001; 0.785, P = 0.0002) compared with other non-invasive markers in the training and validation cohorts, respectively. We developed a simple, clinical scoring system incorporating Fibroscan and APRI to predict significant liver fibrosis in morbidly obese patients.

Background To determine the association between circadian pathway genetic variants and the risk of prostate cancer progression. Methods We systematically evaluated 79 germline variants in nine circadian pathway genes in a cohort of 458 patients with localized prostate cancer as the discovery phase. We then replicated the significant findings in another cohort of 324 men with more advanced disease. The association of each variant with prostate cancer progression was evaluated by a log-rank test and Cox regression. Results A single nucleotide polymorphism of the neuronal PAS domain protein 2 (NPAS2) gene (rs6542993 A>T) was found to be associated with a significantly higher risk of disease progression in both localized (P = 0.001) and advanced (P = 0.039) prostate cancer cases. In silico analysis revealed decreased expression levels of NPAS2 in carriers of the T allele of rs6542993 compared with those carrying the A allele. Consistently, downregulation of NPAS2 expression was associated with more aggressive prostate cancer and poor progression-free survival (log-rank P = 0.002). Conclusions The NPAS2 rs6542993 polymorphism may be a promising biomarker, and may shed light on the pathways that govern prostate cancer progression. Electronic supplementary material The online version of this article (10.1186/s12935-019-0811-4) contains supplementary material, which is available to authorized users.

Pancreatic cancer remains the fourth leading cause of cancer-related death in the USA with a 5-year survival rate of 5 %. The effects of epidermal growth factor receptor and vascular endothelial growth factor A blockade with chemotherapy on pancreatic tumor growth were examined. Mice bearing human PANC-1 cell xenografts were divided into three groups: T-CR (gemcitabine, cisplatin, and 5-fluorouracil), T-TR (cetuximab, bevacizumab, gemcitabine, cisplatin, and 5-fluorouracil), and vehicle control (T). The therapies were administered via intraperitoneal injections every 4 days for seven cycles from 7 weeks after cancer cell implantation. Mice treated with T-TR had significant reductions in tumor weight as compared to the control group (p

Gastric cancer is an important health issue worldwide. Currently, improving the therapeutic efficacy of chemotherapy drugs is an important goal of cancer research. Alpha-7 nicotine acetylcholine receptor (A7-nAChR) is the key molecule that mediates gastric cancer progression, metastasis, and therapy responses; however, the role of A7-nAChR in the therapeutic efficacy of ixabepilone remains unclear. A7-nAChR expression was silenced by small interfering RNA (siRNA) technology. The cytotoxicity of ixabepilone was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and ixabepilone-induced apoptosis was analyzed by flow cytometry and annexin V/propidium iodide (PI) apoptotic assay. The expression patterns of anti-apoptotic proteins (AKT, phospho-AKT, Mcl-1, and Bcl-2) and pro-apoptotic proteins (Bad and Bax) were determined by western blot. Our study found that A7-nAChR knockdown (A7-nAChR-KD) AGS cells were more sensitive to ixabepilone administration than scrambled control AGS cells. We found that A7-nAChR knockdown enhanced ixabepilone-induced cell death as evidenced by the increased number of annexin V-positive (apoptotic) cells. After scrambled control and A7-nAChR-KD cells were treated with ixabepilone, we found that pAKT and AKT levels were significantly reduced in both groups of cells. The levels of Bcl-2 and the anti-apoptotic Mcl-1 isoform increased dramatically after ixabepilone treatment in scrambled control cells but not in A7-nAChR-KD cells. Bad and Bax levels did not change between the treatment group and vehicle group in both A7-nAChR-KD and scrambled control cells, whereas cleaved PARP levels dramatically increased in ixabepilone-treated A7-nAChR-KD cells. Our results demonstrated that knockdown of A7-nAChR enhanced the sensitivity of gastric cancer cells to ixabepilone administration. Thus, the A7-nAChR expression level in patients with gastric cancer may be a good indicator of ixabepilone sensitivity.

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer death worldwide. Cancer metastasis is a major obstacle in clinical cancer therapy. The mechanisms underlying the metastasis of HCC remain unclear. Glucose-regulated protein 94 (GRP94) is a key protein involved in mediating cancer progression, and it is highly expressed in HCC specimens. However, the role of GRP94 in cancer metastasis is unclear. A specific short hairpin RNA (shRNA) was employed to knock down GRP94 gene expression in HCC cell lines. Wound-healing migration, transwell migration, and invasion assays were performed to determine the migration and invasive ability of HCC cells. We demonstrated that silencing GRP94 inhibited HCC cell wound healing, migration, and invasion. Furthermore, our findings indicated that GRP94 knockdown might attenuate HCC cell metastasis by inhibiting CCT8/c-Jun/EMT signaling. Our study indicated that silencing GRP94 significantly reduced the migration and invasion abilities of HCC cells. Moreover, depleting GRP94 inhibited cell migration and invasion by downregulating CCT8/c-Jun signaling. Thus, our data suggest that the GRP94/CCT8/c-Jun/EMT signaling cascade might be a new therapeutic target for HCC.

Hepatocellular carcinoma (HCC) is a crucial health issue worldwide. High glucose-regulated protein 94 (GRP94) expression has been observed in different types of cancer, suggesting a link between tumor progression and GRP94 expression. However, the mechanisms underlying the role of GRP94 in HCC progression remain unclear. We used specific small hairpin RNA (shRNA) to manipulate GRP94 expression in HCC cells. Tissue arrays, MTT assays, xCELLigence assays, and in vivo xenograft model were performed to identify clinicopathological correlations and to analyze cell growth. We found that high GRP94 expression reflected a poor response and a lower survival rate. In vitro and in vivo studies showed that silencing GRP94 suppressed cancer progression. Mechanistically, GRP94 knockdown reduced AKT, phospho-AKT, and eNOS levels but did not influence the AMPK pathway. Our results demonstrated that GRP94 is a key molecule in HCC progression that modulates the AKT pathway and eNOS levels. Our findings suggest that GRP94 may be a new prognostic and therapeutic target for HCC.

Androgen deprivation therapy has constituted the main treatment for prostate cancer; however, tumors ultimately progress to hormone-independent prostate cancer (HIPC), and suitable therapeutic strategies for HIPC are not available. Maspin, which is also known as mammary serine protease inhibitor, has been suggested to be a valuable focus for targeted cancer therapy. Specifically, maspin has been shown to be upregulated after androgen ablation therapy. Gemcitabine is used as a first-line therapy for metastatic castration-resistant prostate cancer, but its disease control rate is low. Furthermore, the role of maspin in the therapeutic efficacy of gemcitabine for HIPC remains unclear. The expression levels of maspin in PC-3 and DU145 cells were determined by real-time PCR and Western blotting. Furthermore, the expression of maspin was silenced using shRNA technology to generate maspin-KD cells. The cytotoxicity of gemcitabine to prostate cancer cells was assessed using 3-[4,5-dimethylthiazol-2-yl]-3,5-diphenyl tetrazolium bromide (MTT) assays, whereas flow cytometry analyses and annexin V-propidium iodide (PI) apoptosis assays were used to assess the ability of gemcitabine to induce apoptosis in maspin-KD and control cells. Additionally, the expression patterns of anti-apoptosis proteins (myeloid cell leukemia 1 (Mcl-1) and B cell lymphoma 2 (Bcl-2)) and pro-apoptosis proteins (Bcl-2-associated death promoter (Bad) and Bcl-2-associated X protein (Bax)) were determined by Western blotting. In this study, PC-3 cells were more resistant to gemcitabine administration than DU145 cells, which correlated with the higher expression levels of maspin observed in PC-3 cells. Furthermore, maspin knockdown enhanced gemcitabine-induced cell death, as evidenced by the increased number of apoptotic cells. Gemcitabine treatment upregulated the levels of anti-apoptosis proteins (Mcl-2 and Bcl-2) in both scrambled control and maspin-KD cells; however, the fold changes in Mcl-1 and Bcl-2 expression were larger in gemcitabine-treated scrambled control cells than in maspin-KD cells. Finally, our findings indicate for the first time that maspin may mediate the therapeutic efficacy of gemcitabine in HIPC. Our results demonstrate that maspin knockdown enhanced the sensitivity of androgen-independent prostate cancer cells to gemcitabine. Therefore, combining gemcitabine with a drug that targets maspin might constitute a valuable strategy for prostate cancer treatment.

Background Semen from the chimpanzee species becomes a colloidal solid after ejaculation. The formation of this copulatory plug is believed to prevent additional spermatozoa of subsequent mating events from accessing the ova. However, this naturally preserved strategy hampers the processes for sperm preparation. In this study, we investigated whether collagenase can be used to degelify the semen plug and accelerate the semen liquefaction process in zoo captive chimpanzee species (Pan troglodytes). Results We showed that incubation of chimpanzee ejaculates with 0.1% type I collagenase efficiently and significantly (p

Glucose-regulated protein 78 (GRP78) is the key regulator of endoplasmic reticular (ER) function. Expression of GRP78 was correlated with malignancy in different cancers. However, the role of GRP78 in the cytotoxic effect of curcumin on colon cancer cells is still unclear. A silencing RNA (siRNA) technique was used to knock down GRP78 expression. The anticancer effects of curcumin were assessed by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, a flow cytometric cell cycle analysis, and a terminal dexynucleotidyl transferase-mediated nick end labeling (TUNEL) assay. HT-29 cells expressed lower GRP78 compared with DLD-1 cells. The MTT assay revealed that HT-29 cells were more resistant to curcumin treatment than DLD-1 cells. GRP78KD cells showed more resistance to curcumin treatment compared with scrambled control cells. Overexpressed GRP78 in HT-29 cells increased the sensitivity to curcumin treatment. According to the cell cycle analysis and TUNEL assay, we found that apoptosis dramatically increased in scrambled control cells compared to GRP78KD DLD-1 cells after curcumin treatment. Finally, we evaluated levels of Bcl-2, BAX, and Bad and found that an increase of Bcl-2 level was observed in GRP78KD cells treated with curcumin. Those results were consistent with the increasing of resistance to curcumin after silencing of GRP78. The levels of GRP78 expression might determine the therapeutic efficacy of curcumin against colon cancer cells.

Thrombomodulin (TM) is highly expressed in endothelial cells and plays the key role in maintaining physical homeostasis. In addition, many pieces of evidence also show that TM contains the diagnostic value for malignant diseases. TM has been found to correlate with metastatic status in multiple cancers, but its role in prostate cancer progression remains unclear. TM expression was determined in prostate cancer cells (DU-145 and PC-3 cells) using real-time PCR and Western blotting. TM expression was manipulated in prostate cancer cells using TM-specific shRNA and an overexpression system. The proliferation, adhesion, and migratory ability of prostate cancer cells expressing various TM levels were determined using the x'Celligence biosensor system and a transwell migration assay. Higher levels of TM transcription and translation were found in DU-145 cells and were negatively correlated with the low migratory ability of DU-145 cells. After silencing TM expression in DU-145 cells, cell growth decreased, but cell adhesion and migration dramatically increased. TM overexpression in PC-3 cells reduced their metastatic ability. We investigated the possible mechanisms of this phenomenon and determined that the enhanced cell migration was mediated through the expression of E-cadherin and vimentin. TM may be a modulator of hormone-independent prostate cancer (HIPC) metastasis. The downregulation of TM expression enhanced the migratory ability of these cells via an increase in vimentin expression and a decrease in E-cadherin expression.

Glucose-regulated protein 78 (GRP78) plays an essential role in embryonic development and in the progression and therapeutic resistance of many cancers. However, little is known about the function of GRP78 in hormone-independent prostate cancer. Here, we found that the expression levels of GRP78 were higher in PC-3 cells than in DU-145 cells. When the expression of GRP78 was silenced using a GRP78-specific small interfering RNA in PC-3 cells, the growth rate and adhesive ability were reduced. Cell migration was dramatically decreased in GRP78-depleted cells. Dissection of the involved signal pathways revealed that maspin expression was upregulated after silencing GRP78 expression. The upregulation of maspin and downregulation of COX-2 may cause the decrease in cell proliferation and migration observed after silencing GRP78 expression. Silencing GRP78 expression may suppress the proliferation, adhesion, and migration of prostate cancer cells via maspin and COX-2 regulation.

Thrombomodulin (TM), a natural anticoagulation factor, maintains circulation homeostasis in endothelial cells. TM has additional roles in modulating inflammation, thrombosis, and carcinogenesis. However, there is little information on the role of TM in the progression and metastasis of ovarian cancer. RNA silencing and cDNA expression vectors were used to manipulate target gene expression in ovarian cancer cells. Cell growth and migration were evaluated by an MTT assay, a wound-healing migration assay, a transwell migration assay, and a biosensor system. In this study, we found that TM silencing may enhance the growth rate of cells. The migratory ability of ovarian cancer cells was enhanced dramatically after TM silencing. TM overexpression in ovarian cells suppressed the proliferation and migration capability. Furthermore, we found that skov-3 cells treated with TM shRNA expressed high levels of fibronectin and vimentin and that the expression of these markers correlated positively with their migratory ability. Our results demonstrate that TM expression may regulate cell growth and migration in ovarian cancer cells. This finding suggests that TM may be a novel prognostic and therapeutic target for ovarian cancer.

Glucose-regulated protein 78 (GRP78) plays an important role in embryonic development and cancer progression. However, there is little information regarding the regulation of GRP78 in hepatocellular carcinoma (HCC) metastasis.We used RNA silencing and cDNA expression vectors to manipulate target gene expression in HCC cells. The transwell migration assay and xCelligence biosensor system were applied to determine the proliferatory and migratory ability of the HCC cells.In this study, we found that GRP78 silencing enhanced cell migration in both HepJ5 and Mahlavu cells. Overexpressed GRP78 in skHep1 cells suppressed the migratory ability. In the insight mechanism dissection for GRP78-mediated cancer migration, we found that downregulation of GRP78 caused the increase of vimentin expression on HCC cells. Suppressed vimentin expression also decreased the migratory ability on HCC, indicating that vimentin expression levels modulated the cell migratory ability.We found that silencing GRP78 in HCC cells may enhance cell migration through the increase of vimentin expression.

Survivin has multiple functions during the progression of cancer. However, the role of survivin in the progression and metastasis of hepatocellular carcinoma (HCC) remains unknown. Survivin expression in HCC cells (Mahlavu and Hep3B) was assessed using reverse transcription real-time PCR and Western blot analyses. In addition, survivin expression in HCC cells was manipulated using small interfering RNA (siRNA) or overexpression and proliferation and transwell migration assays were performed to monitor the effect of manipulated survivin expression on the growth rate and migratory ability of the transfected cells. Among the HCC cell lines tested, we found high endogenous expression of survivin mRNA and protein in Mahlavu cells. After silencing survivin expression in Mahlavu cells, there was a dramatic decrease in the cell growth rate and an increase in the metastatic potential of the cells. Overexpression of survivin in Hep3B cells suppressed the ability of the cell to migrate. The mechanism of enhanced cell migration caused by decreased survivin expression is mediated through the downregulation of glucose-regulated protein 78 (GRP78) and the upregulation of the epithelial-mesenchymal transition (EMT) marker, vimentin. Survivin may mediate metastasis in HCC. The knockdown of survivin expression may enhance cancer metastasis through the downregulation of GRP78 and upregulation of vimentin expression.

Glucose-regulated protein 78 (GRP78) plays an important role in the therapeutic treatment and progression of cancer. However, little is known about the effect of GRP78 expression to curcumin in hepatocellular carcinoma (HCC). In this study, we generated GRP78 knockdown cells (GRP78KD) by a short interfering RNA (siRNA) technique. The antiproliferation effects of curcumin were determined by MTT assay, TUNEL assay, and cell cycle determination. We found that GRP78KD cells were more resistant to curcumin treatment compared with the parental cells in MTT assay. The apoptosis cell population was increased in scrambled-siRNA cells treated with curcumin compared with GRP78KD cells in cell cycle distribution and TUNEL assays. Finally, we found that knocking down GRP78 causes resistance to curcumin treatment through the suppression of caspase-3 and caspase-8 expression levels. We conclude that the expression level of GRP78 may contribute to the therapeutic effect of curcumin on HCC cells.

Temozolomide (TMZ) is an oral alkylating agent that has been widely used in the treatment of refractory glioma, although inherent and acquired resistance to this drug is common. The clinical use of valproic acid (VPA) as an anticonvulsant and mood-stabilizing drug has been reported primarily for the treatment of epilepsy and bipolar disorder and less commonly for major depression. VPA is also used in the treatment of glioma-associated seizures with or without intracranial operation. In this study, we evaluated the potential synergistic effect of TMZ and VPA in human glioma cell lines. Compared with the use of TMZ or VPA alone, concurrent treatment with both drugs synergistically induced apoptosis in U87MG cells as evidenced by p53 and Bax expression, mitochondrial transmembrane potential loss, reactive oxygen species production, and glutathione depletion. This synergistic effect correlated with a decrease in nuclear translocation of the nuclear factor-erythroid 2 p45-related factor and corresponded with reduced heme oxygenase-1 and γ-glutamylcysteine synthetase expression. Pretreatment with N-acetylcysteine partially recovered the apoptotic effect of the TMZ/VPA combination treatment. The same degree of synergism is also seen in p53-mutant Hs683 cells, which indicates that p53 may not play a major role in the increased proapoptotic effect of the TMZ/VPA combination. In conclusion, VPA enhanced the apoptotic effect of TMZ, possibly through a redox regulation mechanism. The TMZ/VPA combination may be effective for treating glioma cancer and may be a powerful agent against malignant glioma. This drug combination should be further explored in the clinical setting.

Given the poor outcome of patients with hormone-resistant (HR) prostate cancer, new strategies are needed to improve the current therapeutic regimens and/or develop novel treatments. We therefore aimed to provide a better understanding of the molecular mechanisms involved in the aggressive tumor behavior of HR and develop more rational anti-tumor therapies. Three HR prostate cancer cell lines (androgen receptor (AR)-positive LNCaP-HR and 22RV1-HR and AR-negative PC-3) were used. Changes in tumor behavior, treatment response, and related signaling in HR were investigated in vitro and in vivo. The results revealed that constitutional activation of STAT3 and overexpressions of DNMT1 were important in the transition of HR prostate cancer. Furthermore, DNMT1 expression was required for the maintenance of STAT3 activation. When DNMT1 activity in HR was blocked, aggressive tumor behavior and treatment resistance could be overcome, which was seen in both in vitro and in vivo experiments. The underlying changes associated with inhibited DNMT1 included less epithelial-mesenchymal changes, less invasion ability, slower tumor growth, and impaired DNA repair ability, which are independent of AR and p53 status. In conclusion, altered DNMT1 expression associated with activated STAT3 may be crucial in the transition of HR. Targeting DNMT1 could be a promising strategy for the treatment of HR prostate, as evidenced by inhibited tumor growth and enhanced radiosensitivity. These findings provide evidence for therapeutically targeting DNMT1 in HR prostate cancer.