Cancer Research

This study explored the effects of microRNA-3178 (miR-3178) on hepatocellular carcinoma (HCC) tumor endothelial cells (TECs) and on the target mRNA. Real-time polymerase chain reaction (PCR) was performed to detect the differential expression of miR-3178 in hepatic sinusoidal endothelial cells (HSECs) and HCC TECs. Furthermore, HCC TECs were transfected with miR-3178 mimic/inhibitor or their respective negative controls. The expression of miR-3178 before and after transfection was confirmed through RT-PCR. The effects of miR-3178 on the proliferation, apoptosis, cell cycle, invasion, migration, and angiogenesis of HCC TECs were also investigated through methyl thiazol tetrazolium assay, flow cytometry, matrigel invasion assay, transwell migration assay, and tube formation assay. Early growth responsive gene 3 (EGR3), as the putative target of miR-3178, was detected through RT-PCR and Western blot. Compared with HSECs, HCC TECs had lower miR-3178 expression levels (P < 0.001). MiR-3178 mimic inhibited proliferation, arrested cell cycle in G1 phase, and increased apoptosis. The numbers of migrated and invaded cells and capillary-like structures were significantly less in the mimic group than in the other groups. MiR-3178 mimic significantly decreased the mRNA and protein expression levels of EGR3. By contrast, miR-3178 inhibitor induced opposite effects. We conclude that miR-3178 was lowly expressed in HCC TECs, and miR-3178 mimic specifically inhibited the proliferation, migration, invasion, and angiogenesis and promoted the apoptosis and G1 phase arrest of HCC TECs in vitro through the inhibition of EGR3 expression. Thus, miR-3178 might be a critical target in HCC therapy.

There are currently no effective molecular targeted therapies for hepatocellular carcinoma (HCC), the third leading cause of cancer-related death worldwide. Enhancer of zeste homolog 2 (EZH2), a histone H3 lysine 27 (H3K27)-specific methyltransferase, has been emerged as novel anticancer target. Our previous study has demonstrated that GSK343, an S-adenosyl-L-methionine (SAM)-competitive inhibitor of EZH2, induces autophagy and enhances drug sensitivity in cancer cells including HCC. In this study, an in silico study was performed and found that EZH2 was overexpressed in cancerous tissues of HCC patients at both gene and protein levels. Microarray analysis and in vitro experiments indicated that the anti-HCC activity of GSK343 was associated with the induction of metallothionein (MT) genes. In addition, the negative association of EZH2 and MT1/MT2A genes in cancer cell lines and tissues was found in public gene expression database. Taken together, our findings suggest that EZH2 inhibitors could be a good therapeutic option for HCC, and induction of MT genes was associated with the anti-HCC activity of EZH2 inhibitors.

Accumulated evidence demonstrated that long non-coding RNAs (lncRNAs) play a pivotal role in tumorigenesis. However, it is still largely unknown how these lncRNAs were regulated by small ncRNAs, such as microRNAs (miRNAs), at the post-transcriptional level. We here use lncRNA HOTTIP as an example to study how miRNAs impact lncRNAs expression and its biological significance in hepatocellular carcinoma (HCC). LncRNA HOTTIP is a vital oncogene in HCC, one of the deadliest cancers worldwide. In the current study, we identified miR-192 and miR-204 as two microRNAs (miRNAs) suppressing HOTTIP expression via the Argonaute 2 (AGO2)-mediated RNA interference (RNAi) pathway in HCC. Interaction between miR-192 or miR-204 and HOTTIP were further confirmed using dual luciferase reporter gene assays. Consistent with this notion, a significant negative correlation between these miRNAs and HOTTIP exists in HCC tissue specimens. Interestingly, the dysregulation of the three ncRNAs was associated with overall survival of HCC patients. In addition, the posttranscriptional silencing of HOTTIP by miR-192, miR-204 or HOTTIP siRNAs could significantly suppress viability of HCC cells. On the contrary, antagonizing endogenous miR-192 or miR-204 led to increased HOTTIP expression and stimulated cell proliferation. In vivo mouse xenograft model also support the tumor suppressor role of both miRNAs. Besides the known targets (multiple 5’ end HOX A genes, i.e. HOXA13), glutaminase (GLS1) was identified as a potential downstream target of the miR-192/-204-HOTTIP axis in HCC. Considering glutaminolysis as a crucial hallmark of cancer cells and significantly inhibited cell viability after silencingGLS1, we speculate that the miR-192/-204-HOTTIP axis may interrupt HCC glutaminolysis through GLS1 inhibition. These results elucidate that the miR-192/-204-HOTTIP axis might be an important molecular pathway during hepatic cell tumorigenesis. Our data in clinical HCC samples highlight miR-192, miR-204 and HOTTIP with prognostic and potentially therapeutic implications.

The inhibition of β-catenin/LEF-1 signaling is an emerging strategy in cancer therapy. However, clinical targeted treatment of the β-catenin/LEF-1 complex remains relatively ineffective. Therefore, development of specific molecular targets is a key approach for identifying new cancer therapeutics. Thus, we attempted to synthesize a peptide (TAT-NLS-BLBD-6) that could interfere with the interaction of β-catenin and LEF-1 at nuclei in human breast cancer cells. TAT-NLS-BLBD-6 directly interacted with β-catenin and inhibited breast cancer cell growth, invasion, migration, and colony formation as well as increased arrest of sub-G1 phase and apoptosis; it also suppressed breast tumor growth in nude mouse and zebrafish xenotransplantation models, showed no signs of toxicity, and did not affect body weight. Furthermore, the human global gene expression profiles and Ingenuity Pathway Analysis software showed that the TAT-NLS-BLBD-6 downstream target genes were associated with the HER-2 and IL-9 signaling pathways. TAT-NLS-BLBD-6 commonly down-regulated 27 candidate genes in MCF-7 and MDA-MB-231 cells, which are concurrent with Wnt downstream target genes in human breast cancer. Our study suggests that TAT-NLS-BLBD-6 is a promising drug candidate for the development of effective therapeutics specific for Wnt/β-catenin signaling inhibition.

Overexpression of Human epididymis protein 4 (HE4) related with a role in ovarian cancer tumorigenesis while little is known about the molecular mechanism alteration by HE4 up regulation. Here we reported that overexpressed HE4 promoted ovarian cancer cells proliferation, invasion and metastasis. Furthermore, human whole genome gene expression profile microarrays revealed that 231 differentially expressed genes (DEGs) were altered in response to HE4, in which MAPK signaling, ECM receptor, cell cycle, steroid biosynthesis pathways were involved. The findings suggested that overexpressed HE4 played an important role in ovarian cancer progression and metastasis and that HE4 has the potential to serve as a novel therapeutic target for ovarian cancer.

Background MicroRNAs (miRNAs) have been demonstrated playing important roles in the procession of prostate cancer cells transformation from androgen-dependence to androgen-independence. Methods We conducted the miRNA microarray and realtime PCR analyses in both androgen-dependent (ADPC) and androgen-independent prostate cancer (AIPC) tissues. We also explored the role of hsa-miR-146a-5p (miR-146a) in MSKCC prostate cancer clinical database. Moreover, the impact of miR-146a on prostate cancer cells apoptosis were detected by Hoechst staining and fluorescence-activated cell sorter (FACS). Its target is predicted by DIANA LAB online database and the result was assumed by western blotting and luciferase assay. Results We demonstrated that miR-146a was down-regulated in AIPC tissues and cell lines compared to that in the ADPC tissues. In MSKCC data re-analyses, we found that miR-146a was underexpressed in metastatic prostate cancer tissues and those with Gleason score >8, moreover, low level of miR-146a represented a high biochemical relapse rate after radical prostatectomy. In the functional analyses, we transfected miR-146a mimics into CPRC cell lines and found miR-146a induced cells apoptosis. In mechanic analyses, we found that miR-146a inhibited the basal level of Rho-associated, coiled-coil containing protein kinase 1 (ROCK1) expression by targeting its 3’UTR and an inverse correlation of expression between miR-146a and ROCK1 was observed. Moreover, caspase 3 activity was stimulated by miR-146a overexpression. Conclusion miR-146a has a critical role in the process of AIPC prostate cancer cells apoptosis through regulation of ROCK/Caspase 3 pathway. Targeting this pathway may be a promising therapeutic strategy for future personalized anti-cancer treatment.

This study defines the role of WWOX in the regulation of epithelial to mesenchymal transition. A group of 164 endometrial adenocarcinoma patients was studied as well as an ECC1 well-differentiated steroid-responsive endometrial cell line, which was transducted with WWOX cDNA by a retroviral system. The relationship between WWOX gene and EMT marker (CDH1, VIM, ZEB1, SNAI1) expression on mRNA (RT-qPCR) and protein levels (western blotting) was evaluated. The EMT processes were also analysed in vitro by adhesion of cells to extracellular matrix proteins, migration through a basement membrane, anchorage-independent growth and MMP activity assay. DNA microarrays (HumanOneArray™) were used to determine WWOX-dependent pathways in an ECC1 cell line. A positive correlation was observed between WWOX and ZEB1, and a negative correlation between CDH1 and VIM. WWOX expression was found to inversely correlate with the risk of recurrence of tumors in patients. However, in the WWOX-expressing ECC1 cell line, WWOX expression was found to be inversely related with VIM and positively with CDH1. The ECC1/WWOX cell line variant demonstrated increased migratory capacity, with increased expression of metalloproteinases MMP2/MMP9. However, these cells were not able to form colonies in suspension and revealed decreased adhesion to fibronectin and fibrinogen. Microarray analysis demonstrated that WWOX has an impact on the variety of cellular pathways including the cadherin and integrin signalling pathways. Our results suggest that the WWOX gene plays a role in the regulation of EMT processes in endometrial cancer by controlling the expression of proteins associated with cell motility, thus influencing tissue remodeling, with the suppression of mesenchymal markers.

BACKGROUND: Non-small-cell lung cancer (NSCLC), the most common lung cancer, leads to the largest number of cancer-related deaths worldwide. There are many studies to identify the differentially expressed genes (DEGs) between NSCLC and normal control (NC) tissues by means of microarray technology. Because of the inconsistency of the microarray data sets, we performed an integrated analysis to identify DEGs and analyzed their biological function. METHODS AND RESULTS: We combined 15 microarray data sets and identified 1063 DEGs between NSCLC and NC tissues; in addition, we found that the DEGs were enriched in regulation of cell proliferation process and focal adhesion signaling pathway. The protein-protein interaction network analysis for the top 20 significantly DEGs revealed that CAV1, COL1A1, and ADRB2 were the significant hub proteins. Finally, we employed qRT-PCR to validate the meta-analysis approach by determining the expression of the top 10 most significantly DEGs and found that the expression of these genes were significantly different between tumor and NC tissues, in accordance with the results of meta-analysis. CONCLUSION: qRT-PCR results indicated that the meta-analysis approach in our study was acceptable. Our data suggested that some of the DEGs, including MMP12, COL11A1, THBS2, FAP, and CAV1, may participate in the pathology of NSCLC and could be applied as potential markers or therapeutic targets for NSCLC.

Background & Aims: gp96, or grp94, is an endoplasmic reticulum (ER)-localized heat shock protein 90 paralog that acts as a protein chaperone and plays an important role for example in ER homeostasis, ER stress, Wnt and integrin signaling, and calcium homeostasis, which are vital processes in oncogenesis. However, the cancer-intrinsic function of gp96 remains controversial. Methods: We studied the roles of gp96 in liver biology in mice via an Albumin promoter-driven Cre recombinase-mediated disruption of gp96 gene, hsp90b1. The impact of gp96 status on hepatic carcinogenesis in response to diethyl-nitrosoamine (DENA) was probed. The roles of gp96 on human hepatocellular carcinoma cells (HCC) were also examined pharmacologically with a targeted gp96 inhibitor. Results: We demonstrated that gp96 maintains liver development and hepatocyte function in vivo, and its loss genetically promotes adaptive accumulation of long chain ceramides, accompanied by steatotic regeneration of residual gp96+ hepatocytes. The need for compensatory expansion of gp96+ cells in the gp96− background predisposes mice to develop carcinogen-induced hepatic hyperplasia and cancer from gp96+ but not gp96− hepatocytes. We also found that genetic and pharmacological inhibition of gp96 in human HCCs perturbed multiple growth signals, and attenuated proliferation and expansion.

B-cell lymphoma/leukemia 10 (BCL10) is an apoptotic regulatory protein related to advanced TNM stage and disease recurrence in oral squamous cell carcinoma (OSCC). However, the regulatory mechanism of BCL10 in OSCC progression is still unknown. Here, we showed that knockdown of endogenous BCL10 could significantly reduce cell migration and invasion abilities, retard cell proliferation by G0/G1 phase accumulation and inhibit tumorigenicity in vivo. In molecular level, we identified S100P as a crucial downstream effector of BCL10-inhibited OSCC progression by high-throughput microarray analysis. S100P messenger RNA and protein expression levels were significantly diminished in silenced-BCL10 clones, and transfected S100P expression plasmids restored migration, invasion, proliferation abilities and tumorigenicity in shBCL10 transfectants. Furthermore, we provided evidence that BCL10 regulated S100P expression through signal transducers and activators of transcription 1 (STAT1) and activating transcription factor 4 (ATF4). Knockdown of BCL10 decreased S100P promoter activity, but showed no effect in truncated STAT1/ATF4 S100P promoter. In addition, we also found that the P50/P65 signaling pathway was involved in BCL10-enhanced OSCC progression. Restored S100P in silenced-BCL10 clones could markedly reverse P65 activation via outside-in signaling. Taken together, we discovered a novel axis of BCL10-regulated OSCC progression via STAT1/ATF4/S100P/P65 signaling, which could predict the prognosis of OSCC and will be beneficial for developing therapeutic strategy against advanced OSCC