Fluorophore-Conjugated Anti-ICOS Antibody Enables Precise Prediction of Therapeutic Response of the STING Agonist in Colorectal Cancer via NIRF Imaging.

The innovation of cancer immunotherapy is improving the prognosis of colorectal cancer (CRC) in clinics. Nevertheless, due to tumor heterogeneity and complex underlying inhibitory mechanisms, the therapeutic response greatly varies among different patients. To optimize the clinical management of CRC patients, it is critical to develop novel approaches for response monitoring and prediction. In the current study, we developed a novel near-infrared fluorescence (NIRF) imaging probe (Cy5.5-ICOS mAb) targeting the inducible T-cell costimulatory receptor (ICOS or CD278) and assessed its capacity for the detection of ICOS+-activated T cells in vivo. ICOS expression was evaluated by flow cytometry and immunofluorescence staining in subcutaneous MC38 models treated with the stimulator of interferon genes (STING) agonist (STINGa). NIRF imaging study was performed 1 day after the last treatment, and tumor volume was monitored every other day with a caliper. A significantly higher optical signal could be detected at tumor regions in STINGa group, compared with that in the PBS group at all time points imaged, and this was in line with ex vivo imaging and immunofluorescence staining study. The data demonstrated that Cy5.5-ICOS mAb could detect ICOS+-activated T cells with high specificity, and ICOS NIRF imaging is a promising strategy for predicting and monitoring immune response in CRC.

Colon Cancer-Related Genes Identification and Function Study Based on Single-Cell Multi-Omics Integration.

Transcriptomes and DNA methylation of colon cancer at the single-cell level are used to identify marker genes and improve diagnoses and therapies. Seven colon cancer subtypes are recognized based on the single-cell RNA sequence, and the differentially expressed genes regulated by dysregulated methylation are identified as marker genes for different types of colon cancer. Compared with normal colon cells, marker genes of different types show very obvious specificity, especially upregulated genes in tumors. Functional enrichment analysis for marker genes indicates a possible relation between colon cancer and nervous system disease, moreover, the weak immune system is verified in colon cancer. The heightened expression of markers and the reduction of methylation in colon cancer promote tumor development in an extensive mechanism so that there is no biological process that can be enriched in different types.

The miR-141/neuropilin-1 axis is associated with the clinicopathology and contributes to the growth and metastasis of pancreatic cancer.

BACKGROUND: Neuropilin-1 (NRP-1) is a non-tyrosine kinase receptor interacting with multiple signaling pathways that underpin the biological behavior and fate of cancer cells. However, in pancreatic cancer, the mechanisms underlying the function of NRP-1 in cell proliferation and metastasis and the involvement of regulatory upstream miRNAs remain unclear. METHODS: Potential miRNAs were mined by using multiple bioinformatics prediction tools and validated by luciferase assays. The expression of NRP-1 and miRNA-141 (miR-141) in pancreatic tissues and cells was examined by immunohistochemistry, immunoblotting and/or real-time RT-PCR. Stable transfected cells depleted of NRP-1 were generated, and regulatory effects of miR-141 were investigated by transfecting cells with miR-141 mimics and anti-miR-141. Assays of cell viability, proliferation, cell cycle distribution, transwell migration and cell scratch were employed. Xenograft tumor models were established to assess the effects of NRP-1 depletion on tumorigenesis and liver metastasis, and therapeutic effects of miR-141 on tumor growth. The role of miR-141/NRP-1 axis in regulating epithelial-mesenchymal transition (EMT) by co-interacting the TGF-ß pathway was examined. RESULTS: In this study, of 12 candidate miRNAs identified, miR-141 showed the strongest ability to regulate NRP-1. In pancreatic cancer tissues and cells, the expression level of NRP-1 was negatively correlated with that of miR-141. NRP-1 was highly expressed in pancreatic cancer tissues compared with normal pancreatic tissues, and its expression levels were positively correlated with tumor grade, lymph metastasis and AJCC staging. NRP-1 depletion inhibited cell proliferation by inducing cell cycle arrest at the G0/G1 phase through upregulating p27 and downregulating cyclin E and cyclin-dependent kinase 2, and reduced cell migration by inhibiting EMT through upregulating E-cadherin and downregulating Snail and N-cadherin. Through downregulating NRP-1, miR-141 mimics showed a similar effect as NRP-1 depletion on cell proliferation and migration. NRP-1 depletion suppressed tumor growth and liver metastasis and miR-141 mimics inhibited the growth of established tumors in mice. NRP-1 depletion and/or miR-141 mimics inhibited the activation of the TGF-ß pathway stimulated by TGF-ß ligand. CONCLUSIONS: The present results indicate that NRP-1 is negatively regulated by miR-141 and the miR-141/NRP-1 axis may serve as potentially valuable biomarkers and therapeutic targets for pancreatic cancer.

A Novel LncRNA-miRNA-mRNA Triple Network Identifies LncRNA RP11-363E7.4 as An Important Regulator of miRNA and Gene Expression in Gastric Cancer.

BACKGROUND/AIMS: Recent evidence has shown that some long non-coding RNAs (lncRNAs) play important roles in various biological processes. However, the regulatory mechanism of lncRNA in gastric cancer (GC) remains unclear. METHODS: We reannotated the GC gene expression profile into a lncRNA-mRNA biphasic profile and integrated the microRNA target data to construct a global GC triple network. A further clustering and random walk with restart analyses was performed on the triple network from the level of topology analyses. Quantitative real-time PCR was used to determine expression of lncRNA RP11-363E7.4. Kaplan-Meier analyses was performed to evaluate the prognostic value of lncRNA RP11-363E7.4. RESULTS: We constructed a gastric cancer lncRNA-miRNA-mRNA network (GCLMN) including six lncRNAs, 332 mRNAs, and 3,707 edges. For the shared lncRNA RP11-363E7.4, the interacting gene and microRNA functional enrichment studies implied that lncRNA RP11-363E7.4 might function as a new regulator in GC. The expression of lncRNA RP11-363E7.4 was downregulated compared with that of paracarcinoma tissues in five GC samples. High expression of lncRNA RP11-363E7.4 was found to be correlated to better overall survival (OS) for GC patients. CONCLUSIONS: This study focused on GC lncRNA-miRNA-mRNA regulatory networks, and found that lncRNA RP11-363E7.4 was a new GC risk lncRNA, which might provide novel insight into a better understanding of the pathogenesis of GC.

Associating liver partition and portal vein ligation for staged hepatectomy versus conventional staged hepatectomy: a meta-analysis.

INTRODUCTION: Controversies persist between associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) and conventional staged hepatectomy. This meta-analysis aims to compare completion, regeneration capacity, and surgical outcomes between the two strategies. EVIDENCE ACQUISITION: We systematically searched PubMed, EMBASE, Cochrane Library, Medline. The main endpoints consisted of completion rate, future liver remnant (FLR) hypertrophy ratio, morbidity, major complication, minor complication, post-hepatectomy liver failure (PHLF) and mortality. Pooled data was assessed by the use of a random-effects model. Odds ratios (OR) were calculated for dichotomous outcomes and mean differences (MD) for continuous outcomes. EVIDENCE SYNTHESIS: Of the 124 identified studies, 7 were eligible and were included in our analysis (N.=525 participants). In the two groups, there was no statistical difference in morbidity (OR=1.62; 95% CI: 0.81-3.20; Z=1.37; P=0.17), minor complication rate (OR=1.27; 95% CI: 0.50-3.21; Z=0.51; P=0.61), PHLF rate (OR=0.87; 95% CI: 0.34-2.22; Z=0.30; P=0.76), mortality (OR=1.68; 95% CI: 0.59-4.83; Z=0.97; P=0.33). Meanwhile, statistical significance was showed in the completion rate (OR=8.29; 95% CI: 2.49-27.53; Z=3.45; P=0.0006), FLR hypertrophy ratio (MD=28.00; 95% CI: 16.06-39.93; Z=4.60; P<0.00001) and major complication rate (OR=1.83; 95% CI: 1.08-3.10; Z=2.26; P=0.02). CONCLUSIONS: Compared with conventional staged hepatectomy, ALPPS provides a higher completion rate and FLR hypertrophy ratio. However, it results in more major complications. Conventional staged hepatectomy is not better than ALPPS in the aspects of minor complication, PHLF, morbidity and mortality.

Dual inhibition of Akt and c-Met as a second-line therapy following acquired resistance to sorafenib in hepatocellular carcinoma cells.

Sorafenib displays a limited efficacy for advanced hepatocellular carcinoma (HCC). Some patients with HCC initially respond to sorafenib, but eventually succumb to the disease, indicating that the acquired resistance to sorafenib reduces its beneficial effects. No alternative drugs are available after the failure of sorafenib therapy. Therefore, investigation of the mechanisms underlying the acquired resistance and development of second-line treatments for sorafenib-resistant HCC are urgently required. In this study, sorafenib-resistant HCC cells generated from sorafenib-sensitive human HCC cells were shown to overproduce hepatocyte growth factor (HGF) and overexpress c-Met kinase and its phosphorylated form, leading to the activation of Akt and ERK (extracellular signaling-regulated kinase) pathways. Use of specific c-Met inhibitors enhanced the effects of sorafenib by inhibiting the growth of sorafenib-resistant HCC cells. Akt inhibitors, a class of second-line therapeutic drugs under investigation for treating HCC in clinical trials, enhanced the effects of sorafenib, but also activated the c-Met pathway in sorafenib-resistant cells. Dual inhibition of Akt and c-Met by their respective inhibitors, MK2206 and capmatinib, additively or synergistically suppressed sorafenib-resistant HCC cells in vitro and sorafenib-resistant HCC xenografts in mice. The anticancer activities of MK2206 mainly rely on its ability to induce cell apoptosis and autophagic death, while capmatinib treatment leads to cell cycle arrest at phase G1. These results provide strong evidence for further investigation on the clinical utility of dual inhibition of Akt and c-Met, particularly MK2206 and capmatinib, as a second-line therapy for advanced HCC that has acquired resistance to sorafenib.

Partial splenic embolization has beneficial effects for the management of gastroesophageal variceal hemorrhage.

BACKGROUND/AIMS: Partial splenic embolization (PSE) is used in the management of gastroesophageal variceal hemorrhage (GEVH). However, it is uncertain whether it has beneficial effects for GEVH patients in preventing variceal recurrence and variceal hemorrhage, as well as promoting overall survival (OS), when it is combined with conventional therapies. MATERIALS AND METHODS: The databases including PubMed, EMBASE, Web of Science, Google scholar, and Cochrane Central Register of Controlled Trials were searched up to 11th of November, 2015. Meta-analyses were performed by using Review Manager 5.3 software for analyzing the risk of bias, Newcastle-Ottawa Scale for assessing the bias of cohort studies, and GRADEprofiler software for assessing outcomes obtained from the meta-analyses. RESULTS: A total of 1505 articles were reviewed, and 1 randomized controlled trial and 5 cohort studies with 244 participants were eligible for inclusion. The pooled hazard ratio (HR) of variceal recurrence is 0.50 (95% confidence interval (CI) 0.37, 0.68; P< 0.00001; I2 = 0%). The pooled HR of variceal hemorrhage is 0.24 (95% CI 0.15, 0.39; P< 0.00001; I2 = 0%). The pooled HR of OS is 0.50 (95% CI 0.33, 0.67; P< 0.00001; I2 = 0%). Meta-analyses demonstrated statistically significant superiority of combinational therapies over conventional therapies in preventing variceal recurrence and variceal hemorrhage and prolonging OS. The complications related to PSE were mild or moderate and nonfatal. CONCLUSIONS: The results indicate that PSE has beneficial effects for GEVH patients, however, future investigation with a larger number of subjects in clinical trials is warranted.

An artificial lncRNA targeting multiple miRNAs overcomes sorafenib resistance in hepatocellular carcinoma cells.

Sorafenib resistance remains a major obstacle for the effective treatment of hepatocellular carcinoma (HCC), and a number of miRNAs contribute to this resistance. However, the regulatory networks of miRNAs are very complex, thus inhibiting a single miRNA may sequentially activate other compensatory pathways. In the present study, we generated an artificial long non-coding RNA (AlncRNA), which simultaneously targets multiple miRNAs including miR-21, miR-153, miR-216a, miR-217, miR-494 and miR-10a-5p. These miRNAs have been shown to be upregulated in sorafenib-resistant cells and participate in the mechanisms underlying sorafenib resistance. The AlncRNA contains tandem sequences of 6 copies of the complementary binding sequences to the target miRNAs and is expressed by an adenoviral vector (Ad5-AlncRNA). Infection of Ad5-AlncRNA into sorafenib-resistant HCC cells blocked the function of miRNAs, and sequentially inhibited the downregulation of PTEN and activation of AKT. Ad5-AlncRNA significantly inhibited proliferation and induced apoptosis of sorafenib-resistant cells and enhanced the effects of sorafenib in vitro and in animal models. Inhibition of autophagy decreased the sensitivity of sorafenib-resistant cells to Ad5-AlncRNA, while its induction had the opposite effect. These results indicate that targeting multiple miRNAs by the artificial lncRNA could be a potential promising strategy for overcoming sorafenib resistance in the treatment of HCC.

Meta-analysis of hand-sewn versus mechanical gastrojejunal anastomosis during laparoscopic Roux-en-Y gastric bypass for morbid obesity.

BACKGROUND: Laparoscopic Roux-en-Y gastric bypass (LRYGB) is one of the most performed bariatric procedures in treating morbid obesity. There is no consensus on which technique used for gastrojejunal anastomosis is optimal. The meta-analysis aimed to solve the issue by comparing hand-sewn with mechanical gastrojejunostomy during LRYGB for morbid obesity. METHODS: PubMed, Embase, Cochrane Library, Scopus, Google Scholar and Research Gate were searched (from inception to April 2016). Primary outcome was operation time. Secondary outcomes were postoperative complications (anastomotic leak, stricture, bleeding, marginal ulcer and wound infection), percent excess weight loss during one-year follow-up, reoperation, and postoperative hospital stay. Odds ratios (OR) were calculated for dichotomous outcomes and mean differences (MD) for continuous outcomes. RESULTS: Twelve trials were included comprising 13,626 patients (3309 hand-sewn vs. 6791 circular vs. 3526 linear). There was no difference in operation time when hand-sewn anastomosis was compared with mechanical gastrojejunostomy (MD, -6.00; 95% confidence interval (CI), -34.85 to 22.85; P = 0.68), circular stapled anastomosis (MD, -5.24; 95% CI, -32.71 to 22.24; P = 0.71) or linear stapled anastomosis (MD, - 3.75; 95% CI, -64.81 to 57.31; P = 0.90). Hand-sewn anastomosis had significantly lower incidence rate of postoperative bleeding (OR, 0.48; 95% CI, 0.31-0.74; P = 0.001) and wound infection (OR, 0.19; 95% CI, 0.08-0.45; P = 0.0002) than circular stapled anastomosis; there were no significant differences in the other secondary outcome. And there were no significant differences in all the comparable outcomes between hand-sewn anastomosis and linear stapled anastomosis. CONCLUSIONS: This meta-analysis revealed no significant differences between mechanical and hand-sewn anastomosis except for greater incidence rates of postoperative bleeding and wound infection with the use of circular staplers. Besides, more trials with adequate power are required and a cost analysis also worth trying. REGISTRATION NO. IN PROSPERO: CRD42015020025.

Analysis of 300 consecutive cases of pancreatic adenocarcinoma in a single-center in China.

BACKGROUND: Most of the reports on the prognostic indicators of patients with pancreatic adenocarcinoma are from developed countries. The present study focused on the prognostic indicators of Chinese patients with pancreatic adenocarcinoma. METHODS: A total of 300 patients with pancreatic adenocarcinoma who had undergone curative resection were included. The resection and R0/R1 resection rates for adenocarcinomas from different parts of the pancreas were calculated and clinical characteristics were analyzed. RESULTS: In 3427 patients diagnosed with pancreatic adenocarcinomas, only 300 (8.8%) were eligible for radical resection. The total median survival of these patients was 19 months, and their 1-, 3-, and 5-year survival rates were 72.5%, 28.0% and 23.4%, respectively. The prognostic factors included socioeconomic status, smoking history, symptoms, high blood glucose, and various tumor characteristics, including perineural and vascular invasion, lymph node metastases, and CA19-9 levels before and after operation. Operation-associated prognostic indicators included operation time, blood loss and transfusions, pancreatic fistula, and complications. Independent predictors of mortality included poor socioeconomic status, smoking history, symptoms, CA19-9, perineural invasion and lymph node metastasis, grade of fistula and complications. Patient survival was not correlated with either resection margin or adjuvant chemotherapy in multivariate analysis. CONCLUSIONS: The survival rates of patients with curative resection for pancreatic adenocarcinoma in China are close to those in developed countries, but curative resection rate is far below. Socioeconomic status, symptoms, and CA19-9 are the three most prominent prognostic factors, which are helpful in patient selection and perioperative care.

The long noncoding RNA colon cancer-associated transcript-1/miR-490 axis regulates gastric cancer cell migration by targeting hnRNPA1.

Colon cancer-associated transcript-1 (CCAT1) is a highly conserved long noncoding RNA that is deregulated in several cancers. However, its role in gastric carcinoma and its post-transcriptional regulation remain poorly understood. In this study, we provide the first evidence that CCAT1 regulates miR-490 in gastric cancer (GC) cells. Interestingly, miR-490 can also repress CCAT1 expression. CCAT1 expression was significantly upregulated, and miR-490 expression was downregulated in GC. The negative correlation between miR-490 and CCAT1 expression was observed in GC tissues. Importantly, CCAT1 contains a putative miR-490-binding site, and deletion of this binding site abolishes their miR-490 responsiveness. Post-transcriptional CCAT1 silencing by miR-490 significantly suppressed GC cell migration. Furthermore, miR-490 directly bound to the hnRNPA1 mRNA 3'-UTR to repress its translation. Inhibition of miR-490 rescued CCAT1 siRNA-mediated suppression of cell migration. hnRNPA1 expression was significantly upregulated in GC specimens, and there was a negative correlation between miR-490 and hnRNPA1 expression and also a positive correlation between hnRNAP1 expression level and CCAT1 level. Taken together, we show for the first time that the CCAT1/miR-490/hnRNPA1 axis promotes GC migration, and it may have a possible diagnostic and therapeutic potential in GC.

Neuropilin-1 is associated with clinicopathology of gastric cancer and contributes to cell proliferation and migration as multifunctional co-receptors.

BACKGROUND: Neuropilin-1 (NRP-1) is a transmembrane glycoprotein participating in the growth and metastasis of cancer cells as multifunctional co-receptors by interacting with the signaling pathways. However, its role in gastric cancer has not yet been clarified. This study aims to investigate whether NRP-1 expression is associated with the clinicopathology of gastric cancer, and involved in the growth and metastasis of gastric cancer cells. METHODS: NRP-1 expression in clinical gastric cancer specimens was examined by immunohistochemistry and its association with clinicopathology analyzed. The expression of NRP-1 in a panel of human gastric cancer cells was examined by real-time RT-PCR and immunoblotting. Stable transfectants depleted of NRP-1, termed MGC-803-NRP(low), were generated from MGC-803 cells. Cell proliferation was analyzed by the Cell Counting Kit-8 and Bromodeoxyuridine incorporation assays, and migrating ability analyzed by migration assays. The xenograft model was used to assess the effects of NRP-1 depletion on tumorigenesis, growth, metastasis and therapeutic potentials. The role of NRP-1 as co-receptors in the signaling pathways stimulated by ligands was examined. The key molecules involved in cell proliferation, migration and related signaling pathways were detected by immunoblotting. RESULTS: Gastric cancer tissues expressed higher levels of NRP-1 compared to normal gastric mucosa. Its expression correlated with clinical staging, tumor differentiation and pathological types. NRP-1 depletion inhibited cell proliferation by inducing cell cycle arrest in the G1/S phase by upregulating p27, and downregulating cyclin E and cyclin-dependent kinase 2. NRP-1 depletion reduced the ability of cells to migrate by inhibiting the phosphorylation of focal adhesion kinase. NRP-1 depletion suppressed tumorigenesis, tumor growth and lung metastasis by inhibiting cell proliferation and tumor angiogenesis in situ. Therapeutic NRP-1 shRNA inhibited the growth of established BGC823 tumors. Depletion of NRP-1 inhibited the activation of VEGF/VEGFR2, EGF/EGFR and HGF/c-Met pathways stimulated by respective recombinant human VEGF-165, EGF and HGF proteins. CONCLUSIONS: The present results indicate that NRP-1 may be a potentially valuable biomarker and therapeutic target for gastric cancer.

MiR-382 inhibits cell growth and invasion by targeting NR2F2 in colorectal cancer.

Colorectal cancer (CRC) is one of the leading causes of cancer death worldwide. MiR-382 has been found to have a decreased expression and the ability to suppress tumorigenesis in certain cancers. However, the role of miR-382 in CRC has not been sufficiently investigated. NR2F2 (also known as COUP-TFII), a member of the steroid/thyroid receptor superfamily, is often aberrantly activated in various tumors, but it is currently unclear whether NR2F2 may be a target of miR-382. In the present study, we investigated the role of miR-382 in CRC and identified the regulation of NR2F2 by miR-382. We observed that miR-382 was aberrantly downregulated in CRC. Transfection with miR-382 mimics impeded the growth, migration, and invasion of CRC cells. The direct binding of miR-382 to the 3' untranslated region (3' UTR) of NR2F2 was confirmed using a luciferase reporter gene assay. We showed that the relative expression levels of NR2F2 were significantly higher in CRC tissues compared with normal adjacent mucosa. A Kaplan-Meier analysis indicated that patients with high NR2F2 expression had a poor overall survival. Knockdown of NR2F2 inhibited CRC cell growth, migration, and invasion. Ectopic expression of NR2F2 mitigated miR-382 suppression of CRC cell proliferation, migration, and invasion. In conclusion, the present study describes a potential mechanism underlying a miR-382/NR2F2 link contributing to CRC development. Our results demonstrate that miR-382 represents a potential strategy against CRC. © 2016 Wiley Periodicals, Inc.

CCL18 promotes the invasion and migration of gastric cancer cells via ERK1/2/NF-κB signaling pathway.

CCL18 is a member of CCL chemokines and is frequently overexpressed in cancer. Elevated CCL18 expression has been reported to be associated with poor prognosis of gastric cancer. However, the molecular mechanisms of CCL18 in gastric cancer cells remain elusive. In our study, we found that CCL18 was highly expressed in different gastric cancer cells. CCL18 stimulation dose-dependently enhanced the invasion and migration of MGC-803 cells. Knockdown of endogenous CCL18 inhibited the invasion and migration of MGC-803 cells, whereas overexpression of CCL18 promoted the invasion and migration of MKN28 cells. We further found that CCL18 increased the expressions of MMP-3 and Slug and decreased the expression of E-cadherin in MGC-803 cells. In addition, CCL18 time-dependently induced activation of ERK1/2, IκBα, and NF-κB. These effects of CCL18 were prevented by ERK1/2 selective inhibitor U0126 as well as NF-κB selective inhibitor BAY117082. Taken together, our findings establish a signaling role for CCL18 in gastric cancer cells and identify that the CCL18/ERK1/2/NF-κB signaling pathway is essential for tumor invasiveness in gastric cancer cells. Thus, our data may provide knowledge for using CCL18 as a novel target for effective diagnosis and treatment of gastric cancer.

2ME2 inhibits the activated hypoxia-inducible pathways by cabozantinib and enhances its efficacy against medullary thyroid carcinoma.

Cabozantinib is a multi-targeted tyrosine kinase inhibitor targeting vascular endothelial growth factor (VEGF) receptor (VEGFR)-2, MET (c-Met, also called hepatocyte growth factor (HGF) receptor), and other receptor tyrosine kinases. Cabozantinib has recently been approved for treating advanced medullary thyroid carcinoma (MTC), but its long-term benefit remains uncertain and dose-dependent adverse events are very common. The present study has demonstrated that 2-methoxyestradiol (2ME2), an inhibitor of hypoxia-inducible factors (HIFs) and a promising anticancer agent under investigation in clinical trials, strengthens anticancer activities of cabozantinib against MTC cells in vitro and in vivo. The activated hypoxia-inducible pathways, which are mainly regulated by HIF-1, contribute to the resistance of hypoxic MTC cells to cabozantinib. Cabozantinib upregulated HIF-1α expression at translational levels and increased the expression of the downstream factors including VEGF, lactate dehydrogenase A (LDHA), HGF, and MET. 2ME2 corrected the activated pathways by cabozantinib through downregulating HIF-1α expression and inhibiting its nuclear translocation in hypoxic MTC cells. Administration of 2ME2 enhanced the efficacy of cabozantinib in suppressing the growth of MTC cell line xenografts and patient-derived xenografts established in mice. Given that 2ME2 targets insensitive hypoxic cancer cells to cabozantinib and can inhibit the activated pathways by cabozantinib, the present results warrant further investigation of 2ME2, particularly in combination with cabozantinib, for the treatment of MTC.

Depletion of histone deacetylase 1 inhibits metastatic abilities of gastric cancer cells by regulating the miR-34a/CD44 pathway.

Overexpression of histone deacetylases (HDACs) is associated with higher metastatic rates and a poor prognosis in gastric cancer. However, the underlying mechanisms involved remain unclear. The present study aimed to investigate the molecular pathways that are involved in HDAC1-mediated metastatic activities in gastric cancer cells. First we used a microRNA (miRNA or miR) microarray to screen potential miRNAs whose expression can be altered by HDAC1 depletion. Of these miRNAs, miR-34a is important as it is often inactivated in cancer cells and acts as a tumor suppressor for various types of cancer. The reverse transcription-quantitative polymerase chain reaction (RT­qPCR) results confirmed that miR-34a was upregulated by HDAC1 knockdown. Cells depleted of HDAC1 had lower abilities to migrate, invade and adhere, which were restored by a miR-34a antagomiR. Depletion of HDAC1 also resulted in impaired microfilaments and microtubules, while co-transfection of the miR-34a antagomiR attenuated these changes in the cellular cytoskeleton. The HDAC1/miR-34a axis regulated the expression and activation of CD44 and its downstream factors including Bcl-2, Ras homolog family member A (RhoA), LIM domain kinase 1 (LIMK-1) and matrix metalloproteinase (MMP)-2. The latter three proteins were responsible for the organization of tubulin and actin cytoskeleton and the formation of cellular pseudopodia. In conclusion, results of the present study indicated that HDAC1 depletion inhibits the metastatic abilities of gastric cancer cells by regulating the miRNA-34a/CD44 pathway, which may be a potential target for the treatment of gastric cancer.

Diagnostic significance of miR-106a in gastric cancer.

As one of the most common malignant tumors, gastric cancer still lacks tumor markers with enough specificity and sensitivity. Therefore the development of novel tumor markers is necessary for early diagnosis in clinics. MicroRNA (miR) has been known to be of unique expressional patterns in various tumors and may work as potential tumor markers for clinical use. This study thus explored the significance of plasma miR-106a in clinical diagnosis of gastric cancer and its effects on proliferation of cancer cells. Plasma miR-106a levels were quantified by real-time quantitative fluorescent PCR methods in 80 cases of gastric cancer patients and healthy individuals to analyze the correlation between miR-106a and clinical features. MiR-106 inhibitor was further transfected into human gastric carcinoma cells for further cell proliferation using CCK-8 approach. MiR-106a was significantly up-regulated in gastric cancer patient plasma samples compared to healthy individuals (P<0.01). The area under ROC curve was 0.895 (95% CI: 0.846~0.943). It has a specificity of 93.8% and a sensitivity of 77.5% in diagnosing gastric cancer. MiR-106a level was also correlated with cancer differentiation stage, lymph node metastasis, TNM stage and tumor size (P<0.05). The down-regulation of miR-106 in gastric carcinoma cells inhibited cell proliferation (P<0.05). MiR-106a was significantly up-regulated in gastric cancer patients and can facilitate the in vitro proliferation of tumor cells. It may work as a biological marker for gastric cancer.

Effect of miR-340 on gastric cancer cell proliferation and apoptosis.

Gastric cancer pathogenesis is a multi-factor, multi-step, complicated process that related to gene abnormal expression. This study intended to explore the miR-340 effect on human gastric cancer cell line SGC-7901 and BGG823 proliferation and apoptosis, as to provide theoretical basis and experimental evidence for potential clinical application. Array was used to screen gastric cancer related abnormal genes. Q-PCR was applied to detect the screened genes expression in tissue and gastric cancer cells. MTT and colony formation assay were performed to evaluate miR-340 impact on gastric cancer proliferation. Flow cytometry was used to determine cell cycle and cell apoptosis. Q-PCR showed that miR-340 overexpressed in gastric cancer tissue significantly compared with normal control (P < 0.01). MiR-340 overexpression can promote SGC-7901 and BGC823 cells proliferation with 50% proliferation rate. Soft agar colony formation assay also showed that miR-340 overexpression can facilitate gastric cancer cell proliferation. Cell cycle analysis revealed that miR-340 overexpression can reduce cell apoptosis. Annexin V/PI staining demonstrated that miR-340 transfection can decrease cell apoptotic rate (4.58%, 1.98%, 2.11%). MiR-340 can promote tumor cell growth and reduce cell apoptosis effectively.

2-Methoxyestradiol synergizes with sorafenib to suppress hepatocellular carcinoma by simultaneously dysregulating hypoxia-inducible factor-1 and -2.

Sorafenib is the approved systemic drug of choice for advanced hepatocellular carcinoma (HCC), but has demonstrated limited benefits because of drug resistance. 2-Methoxyestradiol (2ME2) has been shown to be a promising anticancer drug against various types of cancers and acts by dysregulating hypoxia-inducible factor (HIF)-1. Hypoxic cancer cells are extremely resistant to therapies since they elicit strong survival ability due to the cellular adaptive response to hypoxia, which is controlled by HIF-1 and HIF-2. The present study has demonstrated that sorafenib downregulated the expression of HIF-1α, making the hypoxic response switch from HIF-1α- to HIF-2α-dependent pathways, resulting in upregulation of HIF-2α, which contributes to the insensitivity of hypoxic HCC cells to sorafenib. HIF-2α played a dominant role in regulating VEGF, thus sorafenib in turn increased the expression of VEGF (a downstream molecule of both HIF-1 and HIF-2) and cyclin D1 (a downstream molecule of HIF-2), but reduced the expression of LDHA (a downstream molecule of HIF-1), in hypoxic HCC cells. 2ME2 significantly reduced the expression of both HIF-1α and HIF-2α, and their downstream molecules, VEGF, LDHA and cyclin D1, rendering hypoxic HCC cells to increased sensitivity to 2ME2. 2ME2 also inhibited the nuclear translocation of HIF-1α and HIF-2α proteins, but had no effect on their mRNA expression. 2M2 synergized with sorafenib to suppress the proliferation and induction of apoptosis of HCC cells in vitro and in vivo, and inhibited tumoral angiogenesis. These results indicate that 2ME2 given in combination with sorafenib acts synergistically for treating HCC.