PCAT-1 contributes to cisplatin resistance in gastric cancer through epigenetically silencing PTEN via recruiting EZH2.

The aim of this study was to investigate the functional role and the underlying molecular mechanism of long noncoding RNA (lncRNA) prostate cancer-associated transcript 1 (PCAT-1) in cisplatin resistance of gastric cancer (GC). Our results indicated that PCAT-1 was overexpressed in CDDP-resistant GC tumor tissues and cell lines. High expression of PCAT-1 was closely correlated with short overall survival in patients with GC. Downregulation of PCAT-1 resensitized CDDP-resistant GC cells to cisplatin. In addition, PCAT-1 epigenetically silenced PTEN through binding to the histone methyltransferase enhancer of zeste homolog 2 (EZH2), thus increasing H3K27me3. More importantly, PTEN silencing counteracted PCAT-1 knockdown-mediated enhancement in cisplatin sensitivity of CDDP-resistant GC cells. In summary, PCAT-1 led to cisplatin resistance in GC cells through epigenetically suppressing PTEN expression, providing a novel therapeutic strategy for GC patients with chemoresistance.

HOXA11 gene is hypermethylation and aberrant expression in gastric cancer.

BACKGROUND: Aberrant DNA methylation is an acquired epigenetic alteration that serves as an alternative to genetic defects in the inactivation of tumor suppressor genes and other genes in diverse human cancers. Gastric carcinoma is one of the tumors with a high frequency of aberrant methylation in promoter region. Hence we investigated the promoter methylation status and expression level of HOXA11 gene which may involve in GC development. METHODS: Thirty-two surgical excised gastric cancer specimens, twelve paired adjacent non-cancerous specimens and seven normal gastric mucosas were examined. The methylation status and expression level of HOXA11 gene were determined by bisulfite sequencing polymerase chain reaction (BSP), real-time polymerase chain reaction (RT-PCR) and immunohistochemistry (IHC) respectively. HOXA11 expression was knocked-down with siRNA to mimic HOXA11 gene hypermethylation and ability of cell proliferation and migration was determinate. In addition, we analyzed and correlated the findings with clinicopathological features. RESULTS: The methylation level of HOXA11 gene in gastric cancer tissues and adjacent non-cancerous tissues were higher than those in normal gastric mucosa (P < 0.05). The methylation level was higher in TNM III and IV patients of GC than those in TNM I and II patients (P < 0.05). The expression of HOXA11 mRNA and protein decreased in normal gastric mucosa, peri-cancer tissue and GC (P < 0.05). HOXA11 expression was inversely correlated with DNA methylation (P < 0.05). Knocked-down of HOXA11 expression with siRNA in BGC-823 cells enhanced cell proliferation compared with control, but no significant different was observed in migration ability. CONCLUSION: Hypermethylation and decreased expression of HOXA11 gene may be involved in the carcinogenesis and development of GC and may provide useful information for the prediction of the malignant behaviors of GC. And the expression of HOXA11 is impaired by DNA methylation. However, repression of HOXA11 expression promoted BGC-823 cell proliferation.

Monocyte-macrophages modulate intestinal homeostasis in inflammatory bowel disease.

BACKGROUND: Monocytes and macrophages play an indispensable role in maintaining intestinal homeostasis and modulating mucosal immune responses in inflammatory bowel disease (IBD). Although numerous studies have described macrophage properties in IBD, the underlying mechanisms whereby the monocyte-macrophage lineage modulates intestinal homeostasis during gut inflammation remain elusive. MAIN BODY: In this review, we decipher the cellular and molecular mechanisms governing the generation of intestinal mucosal macrophages and fill the knowledge gap in understanding the origin, maturation, classification, and functions of mucosal macrophages in intestinal niches, particularly the phagocytosis and bactericidal effects involved in the elimination of cell debris and pathogens. We delineate macrophage-mediated immunoregulation in the context of producing pro-inflammatory and anti-inflammatory cytokines, chemokines, toxic mediators, and macrophage extracellular traps (METs), and participating in the modulation of epithelial cell proliferation, angiogenesis, and fibrosis in the intestine and its accessory tissues. Moreover, we emphasize that the maturation of intestinal macrophages is arrested at immature stage during IBD, and the deficiency of MCPIP1 involves in the process via ATF3-AP1S2 signature. In addition, we confirmed the origin potential of IL-1B+ macrophages and defined C1QB+ macrophages as mature macrophages. The interaction crosstalk between the intestine and the mesentery has been described in this review, and the expression of mesentery-derived SAA2 is upregulated during IBD, which contributes to immunoregulation of macrophage. Moreover, we also highlight IBD-related susceptibility genes (e.g., RUNX3, IL21R, GTF2I, and LILRB3) associated with the maturation and functions of macrophage, which provide promising therapeutic opportunities for treating human IBD. CONCLUSION: In summary, this review provides a comprehensive, comprehensive, in-depth and novel description of the characteristics and functions of macrophages in IBD, and highlights the important role of macrophages in the molecular and cellular process during IBD.

P2X4 receptor modulates gut inflammation and favours microbial homeostasis in colitis.

BACKGROUND: Inflammatory bowel disease (IBD) is a non-specific chronic inflammatory disease of the intestine. In addition to genetic susceptibility, environmental factors and dysregulated host immunity, the gut microbiota is implicated in the pathogenesis of Crohn's disease (CD) or ulcerative colitis (UC), the two primary types of IBD. The P2X4 receptor has been demonstrated to have a crucial role in preventing infection, inflammation, and organ damage. However, it remains unclear whether the P2X4 receptor affects IBD and the underlying mechanisms. METHODS: Colitis was induced in mice administrated with dextran sodium sulphate (DSS). 16S rDNA sequencing was used to analyze the gut microbiota in knockout and wild-type mice. Clinical and histopathological parameters were monitored throughout the disease progression. RESULTS: Gene Expression Omnibus analysis showed the downregulation of P2RX4 (P2rx4) expression in colonic tissues from patients or mice with IBD. However, its expression at the protein levels was upregulated on day 4 or 6 and then downregulated on day 7 in C57BL/6 mice treated with DSS. Gene ablation of P2rx4 aggravated DSS-induced colitis accompanying gut microbiota dysbiosis in mice. Moreover, P2X4 receptor-positive modulator ivermectin alleviated colitis and corrected dysregulated microbiota in wild-type C57BL/6 mice. Further antibiotic-treated gut microbiota depletion, cohousing experiment, and fecal microbiota transplantation proved that gut microbiota dysbiosis was associated with the aggravation of colitis in the mouse model initiated by P2rx4. CONCLUSIONS: Our findings elaborate on an unrevealed etiopathophysiological mechanism by which microbiota dysbiosis induced by the P2X4 receptor influences the development of colitis, indicating that the P2X4 receptor represents a promising target for treating patients with CD and UC.

Cronkhite-Canada syndrome: A case report and review of the literature.

Cronkhite -Canada Syndrome (CCS) is a rare non-hereditary disease characterized by multiple polyps in the alimentary tract and ectoderm changes, and there is no clearly diagnostic criteria and treatment methods. A 55-year-old Chinese woman was admitted to our hospital with diarrhea. She was diagnosed with Cronkhite-Canada Syndrome (CCS). The clinical symptoms of the patient included diarrhea, nausea, retching, anorexia, weight loss, and we found that she had alopecia, onychatrophy, rampant caries and skin pigmentation from the physical examination. Gastrointestinal endoscopy revealed multiple polyps in the gastric antrum, stomach body, ileocecal part and colon, and from the microscopically the polype hyperplsique was observed. The patient was treated by eradicating Helicobacter pylori and regulating the intestinal flora disbalance and his diarrhea improved within a short period of time. We suggested that she should take glucocorticoids orally, but the patient refused. Follow-up at 1 year showed that the symptoms of the patient had recurred sometimes, and she had taken Chinese herbal medicine orally a few times. At present, the symptoms of diarrhea are relieved, the weight of the patient has increased, and the hair and nails of the patient have grown again. From this case, we learned CCS can be likely ignored and not be diagnosed promptly because the low morbidity of CCS.

Expression and prognosis analysis of JMJD5 in human cancers.

Background: JumonjiC (JmjC) domain-containing protein 5 (JMJD5) plays an important part in cancer metabolism. However, the prognostic value of JMJD5 in most human cancers is unknown yet. We aimed to examine the expression level and prognostic value of JMJD5, immune cell infiltration in cancer patients, and simultaneously to examine the correlations among them. Materials and methods: The mRNA and protein expression of JMJD5 were analyzed through online Tumor Immune Estimation Resource (TIMER) or immunohistochemistry (IHC) of tissue microarray sections (TMAs) in cancer versus normal tissues. The Kaplan-Meier Plotter databases were used to assess the prognostic values. The connection between the expression of JMJD5 and the abundances of six infiltrating immune cells were explored by TIMER in breast cancer (BRCA), liver hepatocellular carcinoma (LIHC), lung squamous cell carcinoma (LUSC), lung adenocarcinoma (LUAD) and stomach adenocarcinoma (STAD). We used the Cox proportional hazards model to investigate the correlations among clinical outcome, the abundance of immune cell infiltration and JMJD5 expression. Results: We found that the JMJD5 expression was obviously lower in BRCA, LIHC and lung cancer (LUC) but higher in STAD than in normal tissues. High expression of JMJD5 had a better prognosis only in BRCA, LIHC and LUC but a worse prognosis in STAD. The expression of JMJD5 has a significant connection with the abundance of six kind of infiltrating immune cells. The expression of JMJD5 plus the number of immune-infiltrating B cells or macrophages may jointly serve as a prognostic marker in the above four cancers. Conclusion: We provided novel evidence of JMJD5 as an essential prognostic biomarker and perspective therapeutic target in BRCA, LUAD, LIHC and STAD.

Mitochondrial activity regulates the differentiation of skin-derived mesenchymal stem cells into brown adipocytes to contribute to hypertension.

BACKGROUND: Brown adipocytes (BAs) are major components of brown adipose tissue (BAT), which is involved in blood pressure regulation. BAs are derived from multiple progenitors, including PDGFRα+ adipose-derived stem cells (ASCs). Skin-derived mesenchymal stem cells (S-MSCs) have the capacity to differentiate into adipocytes; however, their ability to differentiate into BAs remains unexplored. We aim to study the ability and regulatory mechanism of the differentiation of S-MSCs into BAs and the direct role of BAT in blood pressure regulation. METHODS: Protein expression was measured by flow cytometry or Western blotting, and gene mRNA levels were quantified by real-time quantitative PCR (RT-PCR). To induce the differentiation of S-MSCs into BAs, S-MSCs were stimulated with a brown adipogenic cocktail comprising insulin, IBMX, dexamethasone, triiodothyronine (T3), and rosiglitazone for the indicated periods. The oxygen consumption rate (OCR) was measured with an XF24 Extracellular Flux Analyzer. Mitochondrial mass was determined by flow cytometry and fluorescence staining. Hypertension was induced in WT mice by infusion of angiotensin II (Ang II), and systolic blood pressure (SBP) was measured using a tail cuff. Interscapular brown adipose tissue (iBAT)-deficient mice were generated by surgical removal of the iBAT depot, after which the animals were allowed to recover for 6 days. Aortic, iBAT, and heart tissue sections were analyzed by hematoxylin and eosin (HE) staining. RESULTS: We found that in vitro, S-MSCs isolated from the mouse dermis expressed the stem cell markers CD90/105 and PDGFRα and readily differentiated into BAs. Mitochondrial biogenesis and oxygen consumption were markedly increased during differentiation of S-MSCs into BAs. In vivo, iBAT was converted to white adipose tissue (WAT) in Ang II-induced hypertensive mice. We assessed the direct role of BAT in blood pressure (BP) regulation by using iBAT-deficient mice (generated by surgical removal of iBAT) and C57BL/6 (wild-type (WT)) mice and found that Ang II-induced BP elevation and vascular damage were markedly aggravated in iBAT-deficient mice compared with WT mice. CONCLUSIONS: This study demonstrates that PDGFRα+ S-MSCs are able to differentiate into BAs and that this differentiation is regulated by mitochondrial activity. We also show that BAT plays a direct role in ameliorating Ang II-induced hypertension. The therapeutic potential of BAT for the prevention of hypertension-induced organ remodeling thus warrants further investigation.

Post-transcriptional regulator Rbm47 elevates IL-10 production and promotes the immunosuppression of B cells.

Regulatory B cells (Bregs) are a functionally defined B cell subset, and IL-10 is crucial for the suppressive functions of Bregs. However, little is known regarding how IL-10 production is regulated in B cells. To explore the mechanisms by which IL-10 is regulated in B cells, we used mRNA microarrays to screen for molecules that are upregulated in IL-10-producing B cells and identified RNA-binding motif protein 47 (Rbm47) as a post-transcriptional regulator. Rbm47 was found to promote IL-10 production in B cells. We found that Rbm47 promotes the stability of IL-10 mRNA by binding to AU-rich elements in the 3' untranslated region of Il10 mRNA. In addition, we demonstrated that the overexpression of Rbm47 enabled B cells to facilitate Foxp3+ regulator T-cell induction and reduce the severity of DSS-induced ulcerative colitis. Taken together, these results suggest that Rbm47 plays an important role in regulating IL-10 at the post-transcriptional level, thus promoting the regulatory functions of B cells. The findings presented in this study not only increase our understanding of the post-translational regulation of IL-10 in B cells but also identify a novel strategy for the potential application of Bregs.

Regulation of miR-155 affects the invasion and migration of gastric carcinoma cells by modulating the STAT3 signaling pathway.

Studies investigating the effects of microRNA (miR)-155 on the behavior of tumor cells have concentrated primarily on proliferation and apoptosis. The aim of the present study was to investigate the effect of miR-155 inhibitor on the metastatic and invasive ability of gastric carcinoma cells and whether this effect is mediated via the signal transduction and activators of transcription 3 (STAT3) signaling pathway. The miR-155 inhibitor and miR-155 negative control (NC) were transfected into the AGs and MKN-45 cell lines. The migratory and invasive abilities of the cells were analyzed. The level of phosphorylated (p-)STAT3 and the expression levels of matrix metalloproteinases (MMPs), vascular endothelial growth factor (VEGF) and suppressor of cytokine signaling 1 (SOCS1) were also detected. For the AGS cell line, the cell counts (mean ± standard deviation) for the Transwell migration assay were 98.99±9.13 in the miR-155 NC group and 45.32±4.32 in the miR-155 inhibitor group (P<0.01). For the MKN-45 cell line, the cell counts for the migration assay were 129.99±10.12 and 50.36±5.2 in the miR-155 NC and miR-155 inhibitor groups, respectively (P<0.01). The cell counts of the AGS cell line for the invasion assay were 70.25±7.94 in the miR-155 NC group and 40.68±4.73 in the miR-155 inhibitor group (P<0.05). For the MKN-45 cell line, the cell counts for the invasion assay were 84.63±8.12 and 40.35±4.29 in the miR-155 NC and miR-155 inhibitor groups, respectively (P<0.05). Transfection with the miR-155 inhibitor was able to significantly decrease the level of p-STAT3 in the AGS and MKN-45 cell lines compared with the negative control group (all P<0.05). The levels of MMP2 and MMP9 expression were decreased following transfection with miR-155 in AGS and MKN-45 cells (both P<0.05). Notably, transfection with the miR-155 inhibitor was able to decrease the level of VEGF expression, whilst increasing the SOCS1 expression level compared with the negative control group (both P<0.05). Additionally, the downregulation of miR-155 expression in gastric carcinoma cell lines was able to significantly decrease the expression of VEGF, MMP2 and MMP9, thereby inhibiting the invasion and metastasis of gastric carcinoma cells.

Clinical utilization of serum- or plasma-based miRNAs as early detection biomarkers for pancreatic cancer: A meta-analysis up to now.

BACKGROUND: Pancreatic cancer (PC) is a lethal disease, however current screening methods unable to achieve early diagnosis. Blood-based microRNAs (miRNAs) are promising molecular biomarkers for detecting PC. This meta-analysis summaries studies identifying serum- or plasma-based miRNAs dysregulated in PC patients compared to non-PC cases to evaluate their diagnostic accuracy for characterizing PC. METHODS: A systematically reviews and meta-analysis of published studies was conducted to compare the serum or plasma miRNAs expressions between PC patients and non-PC cases. Summary estimates for sensitivity, specificity, along with other measures of accuracy of miRNAs in the diagnosis of PC were pooled using the random-effects model. I and Q tests were used to assess the heterogeneity of included studies. The Spearman test was used to analyze the threshold effect. RESULTS: Twenty-seven eligible studies were identified after electronic search and literature selection. For single miRNA dysregulation, 32 miRNAs were found to be upregulated in PC patients, and 5 miRNAs were downregulated. Four studies identified a 2-miRNA panel, and 10 studies identified a panel consisting of 3 or more miRNAs which were used to detect PC patients. Additionally, 8 studies combined miRNA panels and carbohydrate antigen 19-9 (CA 19-9) to diagnose PC. The pooled sensitivities for these 4 groups were 0.77 to 0.85, and specificities were 0.70 to 0.87. The highest area under the curve (AUC), 0.9308, was identified using 2 miRNA panels with sensitivity and specificity of 0.79 (0.74-0.83) and 0.85 (0.81-0.89), respectively. There was great heterogeneity of these 4 miRNA groups. Results of Spearman test revealed that there existed a threshold effect on single miRNA group (r=-0.437, P=.001), and none of the other groups (P all>.05). CONCLUSIONS: Serum- or plasma-based miRNAs are capable of distinguishing PC from non-PC with relatively high sensitivity and specificity. In future, miRNAs may be used as promising diagnostic biomarkers for detection of PC.

Knockdown of HOXA5 inhibits the tumorigenesis in esophageal squamous cell cancer.

Homeobox A5 (HOXA5) is a member of the homeobox (HOX) family and was upregulated in many types of tumors. However, its expression and role in esophageal squamous cell carcinoma (ESCC) remain unclear. In this study, the aim of this study was to investigate the expression and function of HOXA5 in ESCC. Our results showed that HOXA5 was highly expressed in ESCC cell lines. The in vitro experiments demonstrated that knockdown of HOXA5 significantly inhibited the proliferation, migration and invasion of ESCC cells. Furthermore, the in vivo experiments showed that knockdown of HOXA5 significantly inhibited the tumor growth of ESCC in mice xenograft model. Finally, sh-HOXA5 inhibited the expression of ß-catenin, cyclin D1 and c-Myc in ESCC cells. Taken together, these data revealed that knockdown of HOXA5 suppressed the proliferation and metastasis partly by interfering with Wnt/ß-catenin signaling pathway in ESCC cells. Therefore, these findings suggest that HOXA5 may be a potential therapeutic target for the treatment of ESCC.

Comparing the long-term efficacy of standard and combined minimally invasive procedures for unresectable HCC: a mixed treatment comparison.

A small proportion of hepatocellular carcinoma (HCC) patients are suitable for surgical resections and various minimally invasive procedures have been introduced as alternatives to surgical resections. However, the relative efficacy of minimally invasive procedures remains to be studied in the current literature. Several popular minimally invasive procedures (monotherapy or combined therapies) were selected for comparison and their relative long-term efficacy were determined by using the statistics of hazard ratio (HR) which evaluates the survival status of HCC patients in one, two, three and four years, respectively. Evidence were obtained from the current literature and synthesized by using the approach of conventional pairwise meta-analysis and network meta-analysis (NMA). Moreover, selected minimally invasive procedures were ranked according to their surface under the cumulative ranking curve (SUCRA) which was produced by NMA in conjunction with the Markov Chain Monte Carlo (MCMC) sampling method. HCC patients treated by combined minimally invasive procedures, particularly transcatheter arterial chemoembolization (TACE) + high intensity focused ultrasound (HIFU), TACE + radiofrequency ablation (RFA), TACE + radiotherapy (RT) and TACE + Sorafenib (SOR) exhibited a significant decrease in the HR compared to those with standard TACE (HR < 1). The combined minimally invasive procedure of TACE + HIFU appears to be the most preferable therapy. PEI seems to be less favorable than other minimally invasive procedures. Combined minimally invasive procedures may be more preferable than standard minimally invasive procedures. Percutaneous ethanol injection (PEI) may not provide adequate efficacy compared to other minimally invasive procedures for unresectable HCC patients.

TSPAN8 promotes gastric cancer growth and metastasis via ERK MAPK pathway.

AIMS: This study was designed to investigate the effects of Tetraspanin 8 (TSPAN8) overexpression and TSPAN8 suppression on gastric cancer cell proliferation and invasion. Furthermore, whether extracellular-signal regulated kinase (ERK) mitogen-activated protein kinase (MAPK) pathway was involved in TSPAN8's function on gastric cancer cells was examined. METHODS: The expression of TSPAN8 in human gastric cancer tissues and gastric cancer cell lines was detected using real-time PCR and western blot analysis. TSPAN8-pcDNA3.1 plasmid or TSPAN8 siRNA was transfected into the gastric cancer cell lines to overexpress or suppress TSPAN8. Cells were treated with U0126 to inhibit ERK MAPK pathway. Cell proliferation and invasion were assessed by MTT and transwell-matrigel assay. RESULTS: TSPAN8 was overexpressed in human gastric cancer tissues and gastric cancer cell lines compared with the normal. TSPAN8 overexpression promoted cell proliferation and invasion, while TSPAN8 suppression inhibited cell proliferation and invasion. TSPAN8 could activate the ERK MAPK pathway in gastric cancer cells, and MEK-ERK inhibition reversed the effects of TSPAN8 overexpression on cell proliferation and invasion. CONCLUSION: This study firstly demonstrated that TSPAN8 promotes gastric cancer cell growth and metastasis at least partially through the activation of ERK MAPK pathway. These findings provided a novel molecular basis for the understanding and treatment of gastric cancer.

Effect of Helicobacter pylori on cyclooxygenase-2 and inducible nitric oxide synthase in patients with gastric precancerous lesions and its clinical significance.

The aim of this study was to investigate the effect of Helicobacter pylori (Hp) on cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) levels in patients with gastric precancerous lesions and its clinical significance. A total of 114 patients with gastric precancerous lesions, 57 whom were positive for Hp (observation group) and 57 of whom were negative for Hp (control group), were selected for the study. The mRNA levels of COX-2 and iNOS in the gastric precancerous lesion tissue from the two groups of patients were analyzed through the reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The protein expression levels of COX-2 and iNOS were analyzed using western blotting and an iNOS kit, respectively. In addition, normal human gastric mucosal GES-1 cells were cultured in vitro and stimulated by Hp for 3, 6, 9 and 12 h. The variations in the mRNA and protein levels of COX-2 and iNOS were then analyzed via RT-qPCR and western blotting. Compared with the control group, the mRNA levels of COX-2 and iNOS in the gastric tissue from the observation group were significantly increased (P<0.05). Furthermore, the expression level of COX-2 and iNOS protein in the gastric tissue from the observation group was significantly higher than that in the tissue from the control group (P<0.05). In vitro analysis showed that the COX-2 and iNOS mRNA and protein levels were significantly increased in the Hp-stimulated normal human gastric mucosal GES-1 cells compared with those in the unstimulated cells. Furthermore, the effect was time-dependent (P<0.05). In conclusion, COX-2 and iNOS are the main inflammatory markers. Hp can induce high expression levels of COX-2 and iNOS in gastric precancerous lesion tissue, which may be associated with the occurrence and development of gastric precancerous lesions.