Oxaliplatin Resistance In Hepatocellular Carcinoma Research Articles

NLRP3/IL-1β induced myeloid-derived suppressor cells recruitment and PD-L1 upregulation promotes oxaliplatin resistance of hepatocellular carcinoma.

Oxaliplatin is commonly used as the first-line chemotherapeutic agent for advanced hepatocellular carcinoma (HCC). Unfortunately, the acquired resistance, limits the effectiveness of oxaliplatin and the underlying mechanisms remain unknown. Therefore, we explored the role of NOD-like receptor protein 3 (NLRP3)/IL-1β in mediating oxaliplatin resistance in HCC. We observed that NLRP3/IL-1β expression was much higher in oxaliplatin-resistant HCC cells. To further understand its impact on drug resistance, we knocked down NLRP3 and observed that it sensitized HCC cells to the growth-inhibitory effects of oxaliplatin and induced cell apoptosis. NLRP3/IL-1β overexpressing tumor cells also attracted polymorphonuclear myeloid-derived suppressor cells. Using mouse models, we demonstrated that NLRP3/IL-1β inhibition by short hairpin RNA or MCC950 effectively overcame oxaliplatin resistance. Furthermore, NLRP3/IL-1β inhibition resulted in reduced expression of PD-L1. We also found that PD-L1 antibody combined with NLRP3/IL-1β blockade displayed significant antitumor effect in HCC. Overall, our study provides compelling evidence supporting the essential role of NLRP3/IL-1β in conferring resistance to oxaliplatin and reshaping the immunosuppressive microenvironment in HCC. Targeting NLRP3/IL-1β presents a potential therapeutic target for overcoming oxaliplatin resistance and reshaping microenvironment of HCC.

LncRNA CCAT1 enhances chemoresistance in hepatocellular carcinoma by targeting QKI-5

A major reason for treatment failure of cancer is acquisition of drug resistance. The specific mechanisms underlying hepatocellular carcinoma (HCC) chemoresistance need to be fully elucidated. lncRNAs involve in drug resistance in some cancers, however, the exact functions of lncRNA colon cancer-associated transcript 1 (CCAT1) in oxaliplatin resistance in HCC are still unknown. Our study indicated that CCAT1 promoted HCC proliferation and reduced the apoptosis induced by oxaliplatin. Knockout of CCAT1 could increased chemosensitivity in vitro and in vivo. Further study found that QKI-5 was an important mediator and blocking of QKI-5/p38 MAPK signaling pathway could enhance oxaliplatin sensitivity. In conclusions, CCAT1 promoted proliferation and oxaliplatin resistance via QKI-5/p38 MAPK signaling pathway in HCC. Targeting CCAT1 in combination with chemotherapeutics may be a promising alternative to reverse drug resistance in HCC treatment.

LSD1-Demethylated LINC01134 Confers Oxaliplatin Resistance Through SP1-Induced p62 Transcription in HCC.

Oxaliplatin (OXA) is one of the most common chemotherapeutics in advanced hepatocellular carcinoma (HCC), the resistance of which poses a big challenge. Long noncoding RNAs (lncRNAs) play vital roles in chemoresistance. Therefore, elucidating the underlying mechanisms and identifying predictive lncRNAs for OXA resistance is needed urgently. RNA sequencing (RNA-seq) and fluorescence in situ hybridization (FISH) were used to investigate the OXA-resistant (OXA-R) lncRNAs. Survival analysis was performed to determine the clinical significance of homo sapiens long intergenic non-protein-coding RNA 1134 (LINC01134) and p62 expression. Luciferase, RNA immunoprecipitation (RIP), chromatin immunoprecipitation (ChIP), and chromatin isolation by RNA purification (ChIRP) assays were used to explore the mechanisms by which LINC01134 regulates p62 expression. The effects of LINC01134/SP1/p62 axis on OXA resistance were evaluated using cell viability, apoptosis, and mitochondrial function and morphology analysis. Xenografts were used to estimate the in vivo regulation of OXA resistance by LINC01134/SP1/p62 axis. ChIP, cell viability, and xenograft assays were used to identify the demethylase for LINC01134 up-regulation in OXA resistance. LINC01134 was identified as one of the most up-regulated lncRNAs in OXA-R cells. Higher LINC01134 expression predicted poorer OXA therapeutic efficacy. LINC01134 activates anti-oxidative pathway through p62 by recruiting transcription factor SP1 to the p62 promoter. The LINC01134/SP1/p62 axis regulates OXA resistance by altering cell viability, apoptosis, and mitochondrial homeostasis both in vitro and in vivo. Furthermore, the demethylase, lysine specific demethylase 1 (LSD1) was responsible for LINC01134 up-regulation in OXA-R cells. In patients with HCC, LINC01134 expression was positively correlated with p62 and LSD1 expressions, whereas SP1 expression positively correlated with p62 expression. LSD1/LINC01134/SP1/p62 axis is critical for OXA resistance in HCC. Evaluating LINC01134 expression in HCC will be effective in predicting OXA efficacy. In treatment-naive patients, targeting the LINC01134/SP1/p62 axis may be a promising strategy to overcome OXA chemoresistance.

LncRNA PCGEM1 mediates oxaliplatin resistance in hepatocellular carcinoma via miR-129-5p/ETV1 axis in vitro.

Hepatocellular carcinoma (HCC) is one of the most severe malignant cancers that leads to high death rate worldwide. Recent research revealed that long non-coding RNAs (lncRNAs) exert a critical role regarding chemoresistance in numerous cancers, including HCC. Our research aimed to explore the function and molecular mechanism of lncRNA PCGEM1 on oxaliplatin resistance of HCC in vitro. Expression of the lncRNA PCGEM1, together with miR-129-5p, and the mRNA level of ETV1 and drug resistance-related genes including LRPA, MDR1 and MDR3 were determined using quantitative real-time polymerase chain reaction (qRT-PCR) in an oxaliplatin-resistant HCC cell line (Hep3B/OXA). Cell Counting Kit-8 (CCK-8) was employed to assess the viability and cell survival rate, and transwell assays were performed to measure the number of migrated or invaded cells. In addition, the relation among lncRNA PCGEM1, miR-129-5p and ETV1 were determined using luciferase assay. Our data indicated that PCGEM1 and ETV1 expression were enhanced in Hep3B/OXA cells. Furthermore, knockdown of lncRNA PCGEM1 significantly decreased the migration, invasion and mRNA expressions of LRPA, MDR1 and MDR3, and the cell viability in Hep3B/OXA cells. The starBase online tool and luciferase assays verified that miR-129-5p targeted PCGEM1 and ETV1, signifying that PCGEM1 could enhance ETV1 expression via suppressing miR-129-5p. Our findings demonstrated that PCGEM1 modulated oxaliplatin resistance by targeting the miR-129-5p/ETV1 pathway in HCC in vitro, suggesting a potential strategy for the treatment of chemoresistant HCC.

Mechanism and Molecular Network of RBM8A-Mediated Regulation of Oxaliplatin Resistance in Hepatocellular Carcinoma.

RNA-binding motif protein 8A (RBM8A) is abnormally overexpressed in hepatocellular carcinoma (HCC) and involved in the epithelial-mesenchymal transition (EMT). The EMT plays an important role in the development of drug resistance, suggesting that RBM8A may be involved in the regulation of oxaliplatin (OXA) resistance in HCC. Here we examined the potential involvement of RBM8A and its downstream pathways in OXA resistance using in vitro and in vivo models. RBM8A overexpression induced the EMT in OXA-resistant HCC cells, altering cell proliferation, apoptosis, migration, and invasion. Moreover, whole-genome microarrays combined with bioinformatics analysis revealed that RBM8A has a wide range of transcriptional regulatory capabilities in OXA-resistant HCC, including the ability to regulate several important tumor-related signaling pathways. In particular, histone deacetylase 9 (HDAC9) emerged as an important mediator of RBM8A activity related to OXA resistance. These data suggest that RBM8A and its related regulatory pathways represent potential markers of OXA resistance and therapeutic targets in HCC.

Remodeling of hepatic stellate cells orchestrated the stroma-derived oxaliplatin-resistance through CCN3 paracrine in hepatocellular carcinoma

BackgroundHepatic stellate cells (HSCs) have a key role in fibrogenesis and in the filtrates of the hepatocellular carcinoma (HCC) stroma, in which they are remodeled and play a critical role in HCC progression. However, the precise role of HSCs trending, infiltration and paracrine in orchestrating the stroma-derived oxaliplatin-resistance in HCC is still vague.MethodsThe chemo-resistant models were established to explore the correlation between HSC cells and the condition of chemoresistance. The HCC clinical samples were collected to confirm this phenomenon. Then, the relationship between secretory CCN3 from oxaliplatin-resistant HCC and the infiltration of HSCs in associated HCC microenvironment was evaluated. Finally, the role and mechanism of HSCs remodeling in the orchestration of oxaliplatin-resistant HCC were explored.ResultsThe increased infiltration of HSCs and collagen accumulation were found in the microenvironment of oxaliplatin-resistant HCC. The cDNA profiles of the oxaliplatin-resistant HCC was reanalyzed, and CCN3 was one of the significantly increased genes. In HCC clinical samples, the levels of CCN3 and α-SMA are positively correlated, and high expression of CCN3 and α-SMA are positively associated with malignant phenotype and poor prognosis. Then the enhanced abilities of migration and proliferation of HSCs, and elevation of the cytokines paracrine from HSCs relating to HCC malignancy were proved in vitro and in vivo, and which were related to CCN3-ERK signaling pathway activation.ConclusionsHSCs remodeling are positively related to CCN3 paracrine in hepatocellular carcinoma, which orchestrated the stroma-derived resistance to chemotherapy in HCC.

Connexin 32 downregulation is critical for chemoresistance in oxaliplatin-resistant HCC cells associated with EMT.

Background: Oxaliplatin (OXA)-based chemotherapy is critical in the management of advanced hepatocellular carcinoma (HCC); however, acquired drug resistance has largely restricted its clinical efficacy. This study aims to explore the key mechanisms and regulatory factors determining chemosensitivity in HCC.Methods: We developed OXA-resistant (OR) HCC cells and used multiple methods, including real-time RT-PCR, Western blot, immunofluorescence, transwell invasion assay, wound-healing assay, MTT assay, gene transfection, and immunohistochemistry to achieve our goals.Results: We found that OR HCC cells showed a typical epithelial–mesenchymal transition (EMT) phenotype. Meanwhile, the expression of Cx32, a major member of the liver connexin (Cx) family, was lowly expressed in OR HCC cells. Downregulation of Cx32 in parental HCC cells led to EMT induction and thereby reduced OXA cytotoxicity, while Cx32 upregulation in OR HCC cells could reverse the EMT phenotype and partially restore chemosensitivity to OXA. Finally, in human HCC tissue samples, Cx32 was positively correlated with the expression of the EMT marker E-cadherin and negatively correlated with the expression of Vimentin.Conclusion: Our findings demonstrated that downregulation of Cx32 may be an important determinant for HCC cells to acquire EMT-related acquired drug resistance to OXA, and targeting Cx32 could be a novel strategy to overcome OXA resistance in HCC.

Long non-coding RNA KCNQ1OT1 modulates oxaliplatin resistance in hepatocellular carcinoma through miR-7-5p/ ABCC1 axis

The underlying functions of long non-coding RNAs (lncRNAs) on chemoresistance in multiple cancers have been testified. However, the function and mechanism of lncRNAs on chemoresistance in hepatocellular carcinoma are still confused. In this study, we concentrated on the function and mechanism of KCNQ1OT1 on oxaliplatin resistance in hepatocellular carcinoma. Results showed that KCNQ1OT1 was significantly up-regulated in oxaliplatin-resistant HepG2 and Huh7 cells. Moreover, knockdown of KCNQ1OT1 inhibited the cell proliferation, migration, invasion and reduced the expression of drug-resistant gene (MRP5, MDR1, LRP1). Additionally, bioinformatics analysis and dual-luciferase reporter assay showed that miR-7-5p directly targeted the 3′-UTR of miR-7-5p and ABCC1 mRNA, indicating that KCNQ1OT1 regulated the expression of ABCC1 via endogenous sponging miR-7-5p. Conclusively, KCNQ1OT1 modulated oxaliplatin resistance in hepatocellular carcinoma through miR-7-5p/ABCC1 axis, indicating a novel approach for the treatment of hepatocellular carcinoma.

MicroRNA-125b reverses oxaliplatin resistance in hepatocellular carcinoma by negatively regulating EVA1A mediated autophagy

EVA1A (also known as transmembrane protein 166) is a transmembrane protein involved in the regulation of autophagy that acts as an adaptor protein to recruit or bind proteins in the lysosome or endoplasmic reticulum. In the present study, we identified EVA1A as a target of microRNA-125b (miR-125b), a member of a highly conserved family of miRNAs that has been proposed as a biomarker for hepatocellular carcinoma (HCC). Analysis of oxaliplatin-sensitive and oxaliplatin-resistant HCC cell lines showed that miR-125b is downregulated in resistant cells and its overexpression in sensitive cells decreased resistance to oxaliplatin by inhibiting cell proliferation, migration and epithelial–mesenchymal transition (EMT). EVA1A expression was shown to be upregulated in tissue samples from oxaliplatin-resistant HCC patients, and its ectopic expression partially induced autophagy and reversed the effect of miR-125b on inhibiting the growth of oxaliplatin-resistant cell lines and xenograft tumors. Taken together, our results suggest that miR-125b plays a role in the resistance of HCC cells to chemotherapy via a mechanism involving the downregulation of EVA1A-mediated autophagy.

Sphingosine kinase 1 overexpression is associated with poor prognosis and oxaliplatin resistance in hepatocellular carcinoma.

Sphingosine kinase 1 (SphK1) is a tumor-associated protein overexpressed in numerous types of cancer and is involved in the regulation of resistance to multiple chemotherapeutic agents. However, the role of SphK1 in the resistance of hepatocellular carcinoma (HCC) to oxaliplatin remains unclear. In the present study, the transcriptional levels of SphK1 were analyzed in 21 patients with HCC and the SphK1 expression levels were identified to be significantly upregulated in HCC tissue compared with that in adjacent normal tissue samples (P<0.001). High SphK1 expression correlated with shorter overall survival times in patients with HCC (P<0.05). Furthermore, SphK1 expression levels and activity were analyzed in a series of HCC cell lines and they were both demonstrated to be associated with resistance to oxaliplatin. Conversely, the knockdown of SphK1 protein expression resulted in decreased oxaliplatin resistance in SK-Hep1 and HCCLM3 cell lines. In addition, the results of the current study demonstrated that the downregulation of SphK1 decreased the levels of phosphorylated AKT serine/threonine kinase (Akt) and glycogen synthase kinase-3β (GSK3β), suggesting that SphK1 promotes oxaliplatin resistance of HCC cells via modulation of the Akt/GSK3β signaling pathway. To the best of our knowledge, the present study is the first to report that SphK1 is associated with poor prognosis and oxaliplatin resistance in HCC. Thus, the findings of the current study have provided a direction for the identification of novel therapeutic targets for the treatment of HCC.

ID1 promotes hepatocellular carcinoma proliferation and confers chemoresistance to oxaliplatin by activating pentose phosphate pathway

BackgroundDrug resistance is one of the major concerns in the treatment of hepatocellular carcinoma (HCC). The aim of the present study was to determine whether aberrant high expression of the inhibitor of differentiation 1(ID1) confers oxaliplatin-resistance to HCC by activating the pentose phosphate pathway (PPP).MethodsAberrant high expression of ID1 was detected in two oxaliplatin-resistant cell lines MHCC97H–OXA(97H–OXA) and Hep3B–OXA(3B–OXA). The lentiviral shRNA or control shRNA was introduced into the two oxaliplatin-resistant cell lines. The effects of ID1 on cell proliferation, apoptosis and chemoresistance were evaluated in vitro and vivo. The molecular signaling mechanism underlying the induction of HCC proliferation and oxaliplatin resistance by ID1 was explored. The prognostic value of ID1/G6PD signaling in HCC patients was assessed using the Cancer Genome Atlas (TCGA) database.ResultsID1 was upregulated in oxaliplaitin-resistant HCC cells and promoted HCC cell proliferation and oxaliplatin resistance. Silencing ID1 expression in oxaliplaitin-resistant HCC cell lines inhibited cell proliferation and sensitized oxaliplaitin-resistant cells to death. ID1 knockdown significantly decreased the expression of glucose-6-phosphate dehydrogenase (G6PD), a key enzyme of the PPP. Silencing ID1 expression blocked the activation of G6PD, decreased the production of PPP NADPH, and augmented reactive oxygen and species (ROS), thus inducing cell apoptosis. Study of the molecular mechanism showed that ID1 induced G6PD promoter transcription and activated PPP through Wnt/β-catenin/c-MYC signaling. In addition, ID1/G6PD signaling predicted unfavorable prognosis of HCC patients on the basis of TCGA.ConclusionsOur study provided the first evidence that ID1 conferred oxaliplatin resistance in HCC by activating the PPP. This newly defined pathway may have important implications in the research and development of new more effective anti-cancer drugs.

Downregulated DYRK2 expression is associated with poor prognosis and Oxaliplatin resistance in hepatocellular carcinoma

We aimed to investigate the molecular mechanisms of DYRK2 and the HCC sensitivity to Oxaliplatin in DYRK2-depleted HCC cells. HCC tissue specimens were obtained from 86 HCC patients during hepatectomy. We used immunohistochemistry and western blot to analyze DYRK2 expression in HCC tissues and cell lines, and used siRNA transfection to decrease DYRK2 expression in HCC cells. Flow cytometry and CCK-8 assay were detected in cell cycle progression, cell proliferation and the efficacy of Oxaliplatin, DYRK2 was down-regulated in HCC tissues, compared with adjacent nontumor ones. The significant correlation between DYRK2 expression and clinicopathologic factors was apparently shown in the immunohistochemical and statistical analyses. The expression of DYRK2 was significantly associated with histological grade of HCC patients. Univariate and multivariate survival analyses revealed that DYRK2 was a significant predictor for overall survival of HCC patients. The depletion of DYRK2 promoted HCC cell proliferation, and increased resistance to Oxaliplatin. These data showed that the downregulated expression of DYRK2 in HCC tumor tissues could promote the proliferation of HCC cells. In addition, reducing DYRK2 expression was associated with poor prognosis and Oxaliplatin resistance in HCC.

Upregulated HOXC8 Expression Is Associated with Poor Prognosis and Oxaliplatin Resistance in Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related deaths worldwide. It is indispensable to understanding molecular mechanisms of HCC progression and to developing clinically useful biomarkers for this disease. In this article, we examined whether HOXC8 was associated with the poor prognosis of hepatocellular carcinoma and explored the possible underlying mechanism. The HOXC8 and Ki67 expression levels in 86 patients with hepatocellular carcinoma were examined using immunohistochemistry. HOXC8 levels in HCC cells were downregulated by siRNA transfection. The cycle progression and cell proliferation status of HCC cells and the oxaliplatin effectiveness were evaluated by flow cytometry and CCK-8 assay. HOXC8, CyclinD1, PCNA, Nkd2, and cleaved caspase-3 levels were detected by western blot. HOXC8 was upregulated in HCC tissues, compared with adjacent non-tumor ones. HOXC8 expression levels in 86 patients with hepatocellular carcinoma were positively correlated with histological grade. Univariate and multivariate survival analysis revealed that HOXC8 was a significant predictor for overall survival of HCC patients. HOXC8 siRNA knockdown delayed the G1-S phase transition, inhibited cell proliferation, and attenuated resistance to oxaliplatin. HOXC8 promoted HCC proliferation and predicted poor prognosis. Furthermore, upregulated HOXC8 expression was associated with oxaliplatin resistance in hepatocellular carcinoma.

Secretory clusterin contributes to oxaliplatin resistance by activating Akt pathway in hepatocellular carcinoma

Secretory clusterin (sCLU) is expressed in numerous cancers and is associated with the resistance to chemotherapy. However, the role of sCLU in the resistance of hepatocellular carcinoma (HCC) to oxaliplatin (OXA), a recently used third-generation platinum agent, remains unclear. The stable transfectants that are depleted of or overexpress sCLU and OXA-resistant cells were generated using human HCC cells. Overexpression of sCLU abrogated OXA-induced inhibition of cell growth and cell apoptosis, but depletion of sCLU synergized with OXA to inhibit cell growth and enhance cell apoptosis, by regulating proteins involved in mitochondrial apoptosis pathways, such as Bcl-2, Bax, Bcl-xL and caspase-9, and affecting phosphorylation of Akt and GSK-3β. Overexpression of sCLU in either OXA-resistant cells or stable transfectants that overexpress sCLU significantly increased phosphorylated Akt. However, specific inhibition of Akt enhanced sensitivity of sCLU-overexpressing cells to OXA, but had no effect on sCLU expression, suggesting that the regulatory effects between sCLU and pAkt may be in a one-way manner in HCC cells. The expression levels of sCLU affected the therapeutic efficacy of OXA to treat HCC tumors established in immunodeficiency mice. The results have demonstrated that sCLU contributes to OXA resistance by activating Akt pathway, indicating that sCLU may be a novel molecular target for overcoming OXA resistance in HCC.