Rifaximin Improves Visceral Hyperalgesia via TRPV1 by Modulating Intestinal Flora in the Water Avoidance Stressed Rat.

BACKGROUND: Rifaximin is effective in relieving pain symptoms with IBS patients, although the mechanisms were not clear. The aims of the research were to investigate whether the visceral hyperalgesia was alleviated by rifaximin via TRPV1 channel in rats. METHODS: Rats were subjected to water avoidance stress (WAS) and were pretreated with rifaximin by oral gavage. The visceromotor response to colorectal distension was measured. The changes of TRPV1 in peripheral and central neurons of rats were detected by immunofluorescence, western blot method, and RT-PCR. Bacterial 16S ribosomal DNA in ileal contents was assessed using the Illumina MiSeq platform. The effect of intestinal flora on TRPV1 channel was observed by fecal microbiota transplantation (FMT) methods. RESULTS: Rifaximin could relieve the visceral hyperalgesia and reduce the TRPV1 expression of neurons and ileum mucosa in rats induced by WAS. The reduced relative abundance of intestinal flora induced by WAS could be partly prevented by rifaximin. The electromyographical activities and immunoreactivity of TRPV1 in rats could be changed after FMT. CONCLUSIONS: Rifaximin could improve visceral hyperalgesia via TRPV1 channels of peripheral and central neurons by modulating intestinal flora in rats.

Vitamin D Signaling Pathways Confer the Susceptibility of Esophageal Squamous Cell Carcinoma in a Northern Chinese Population.

Experimental studies have determined the chemopreventive effects of vitamin D against the esophageal squamous cell carcinoma (ESCC); however, results from the epidemiological studies are not yet well established. The current study aimed to evaluate the associations between plasma vitamin D levels and variants on vitamin D metabolic-related genes with the risks for ESCC. A hospital-based case-control study was performed. Five hundred eighty-two ESCC patients and 569 controls were recruited in a Northern Chinese population. Common variants on vitamin D metabolism-related genes CYP24A1, DHCR7, GC, CYP27B1, and vitamin D receptor (VDR) and the plasma 25(OH)D level were determined. The unconditional logistic regression method was applied to determine the associations between the variants and vitamin D level and ESCC. Higher plasma 25(OH)D was associated with a reduced risk for ESCC, especially for rs2296241, rs11568820, and rs4646536. The variants rs2296241 on CYP24A1 and rs11568820 on VDR are significantly associated with ESCC cancer. Vitamin D signaling pathways may participate in the ESCC development. Further studies with larger sample size are warranted to confirm the results. Intervention studies are needed to determine whether vitamin D supplementation may reduce the ESCC risk in the Chinese population.

MicroRNA-429 inhibits the migration and invasion of colon cancer cells by targeting PAK6/cofilin signaling.

MicroRNAs (miRs), a class of non-coding RNAs 18-25 nucleotides in length, can lead to mRNA degradation or inhibit protein translation by directly binding to the 3'-untranslational region (UTR) of their target mRNAs. The deregulation of miR-429 has been suggested to be involved in the development and progression of colon cancer. However, the detailed molecular mechanism involved remains to be determined. The aim of the present study was to investigate the role of miR-429 in the regulation of migration and invasion of colon cancer cells using RT-qPCR and western blotting. The results showed that the expression of miR-429 was reduced in colon cancer cell lines, when compared to a normal colon epithelial cell line. Treatment with DNA demethylation agent 5-aza-2'-deoxycytidine and histone deacetylase inhibitor phenylbutyrate (PBA), or transfection with the pre-miR-429 lentivirus plasmid led to the upregulation of miR-429 expression, as well as inhibition of migration and invasion in colon cancer cells. Investigation of the molecular mechanism showed that PAK6 was a novel target of miR-429, and the expression of PAK6 was upregulated in colon cancer tissues and cell lines, and was negatively regulated by miR-429 in colon cancer cells. Moreover, the cofilin signaling acted as a downstream effector of miR-429 in colon cancer cells. In conclusion, the results of the present study suggested that miR-429 inhibits the migration and invasion of colon cancer cells, partly at least, by mediating the expression of PAK6, as well as the activity of cofilin signaling. Therefore, miR-429 is as a potential molecular target for the treatment of colon cancer.

Genetic association between CD95 rs2234767 polymorphism and cervical cancer risk: a meta analysis.

BACKGROUND: CD95 rs2234767 polymorphism in the promotor region of CD95 gene has been implicated in several studies of cervical cancer. However, the results have not been conclusively established. OBJECTIVE: The main aim of this study was to deal with the controversy with respect to the correlation between CD95 rs2234767 polymorphism and risk of cervical cancer through a meta-analysis. METHODS: Association studies that pertain to CD95 rs2234767 polymorphism and risk of cervical cancer were identified up to May 26, 2014. ORs and 95% CIs were calculated assuming AA versus GG, AA + AG versus GG, AA versus AG + GG, A versus G and AG versus GG genetic models. RESULTS: A total of 5 case-control studies were included in this meta-analysis. Overall, no significant effect modification of cervical cancer risk was revealed either at the genotypic or the allelic level for CD95 rs2234767 polymorphism. This null association persisted in the stratified analysis of Asian population. CONCLUSIONS: These findings revealed that CD95 rs2234767 polymorphism may not act as a causative agent of cervical cancer. Further evidence is needed to confirm our findings.

Effects of PLCE1 gene silencing by RNA interference on cell cycling and apoptosis in esophageal carcinoma cells.

Esophageal squamous cell carcinoma (ESCC) is one of the most malignancies with a poor prognosis. The phospholipase C? gene (PLCE1) encodes a novel ras-related protein effector mediating the effects of R-Ras on the actin cytoskeleton and membrane protrusion. However, molecular mechanisms pertinent to ESCC are unclear. We therefore designed PLCE1-special small interfering RNA and transfected to esophageal squamous cell (EC) 9706 cells to investigate the effects of PLCE1 gene silencing on the cell cycle and apoptosis of ESCC and indicate its important role in the development of ESCC. Esophageal cancer tissue specimens and normal esophageal mucosa were obtained and assayed by immunohistochemical staining to confirm overexpression of PLCE1 in neoplasias. Fluorescence microscopy was used to examine transfection efficiency, while the result of PLCE1 silencing was examined by reverse transcription (RT-PCR). Flow cytometry and annexin V apoptosis assays were used to assess the cell cycle and apoptosis, respectively. Expression of cyclin D1 and caspase-3 was detected by Western-blotting. The level of PLCE1 protein in esophageal cancer tissue was significantly higher than that in normal tissue. After transfection, the expression of PLCE1 mRNA in EC 9706 was significantly reduced, compared with the control group. Furthermore, flow cytometry results suggested that the PLCE1 gene silencing arrested the cell cycle in the G0/G1 phase; apoptosis was significantly higher than in the negative control group and mock group. PLCE1 gene silencing by RNAi resulted in decreased expression of cyclin D1 and increased expression of caspase-3. Our study suggests that PLCE1 may be an oncogene and play an important role in esophageal carcinogenesis through regulating proteins which control cell cycling and apoptosis.

[The relationship between C20orf54 gene rs3746804 position single nucleotide polymorphism and susceptibility to esophageal squamous cell carcinoma].

OBJECTIVE: To explore the association of C20orf54 gene rs3746804 position single nucleotide polymorphism and susceptibility to esophageal squamous cell carcinoma (ESCC). METHODS: Purification of genomic DNA from whole blood was used the Maxwell(16) System. rs3746804 in C20orf54 was detected by direct sequencing in 434 ESCC patients from Changzhi (Shanxi province) and Linzhou (Henan province) and 554 healthy controls from Changzhi, Linzhou and including immigrators from Linzhou to Changzhi. RESULTS: For rs3746804, the genotypic frequencies of CT (37.5% vs 51.0%, 37.5% vs 52.0%), CC (44.2% vs 34.8%, 44.2% vs 33.0%) in Changzhi ESCC patients showed significant differences with healthy Changzhi controls and the healthy immigrator controls (all P < 0.05), and the frequencies of TT (18.3% vs 4.1%) and CC (44.2% vs 54.6%) in Changzhi ESCC patients showed significant differences with Linzhou ESCC patients (all P < 0.05). The genotypic frequencies of TT (4.1% vs 15.0%), CT (41.2% vs 52.0%) and CC(54.6% vs 33.0%) showed significant differences between Linzhou ESCC patients and the healthy immigrator controls (all P < 0.05), and the frequencies of TT (4.1% vs 14.1%) and CC(54.6% vs 34.8%) showed significant differences between Linzhou ESCC patients and Changzhi healthy controls (all P < 0.01). Meanwhile, there were significant differences between ESCC patients (including Changzhi and Linzhou ESCC patients) and healthy controls (including the healthy Changzhi, Linzhou and immigrator controls) in genotypic frequencies of CT (39.2% vs 48.7%) and CC (48.8% vs 38.2%) (all P < 0.01). CT and CT + TT genotype could decrease the risk of ESCC compared with the CC genotype (OR = 0.630, 95%CI 0.481 - 0.826; OR = 0.654, 95%CI 0.507 - 0.844). CONCLUSION: There is a closed relationship between SNP rs3746804 in C20orf54 and susceptibility to ESCC.

[A comparison and significance of plasma riboflavin levels in patients with esophageal squamous cell carcinoma versus Linzhou healthy migrants in Changzhi of Shanxi].

OBJECTIVE: To study the relationship between plasma riboflavin levels and esophageal squamous cell carcinoma. METHODS: We detected and compared plasma concentrations of riboflavin in patients with esophageal squamous cell carcinoma (ESCC) and immigrants of Linzhou living in Changzhi. Plasma riboflavin levels were quantified in 445 ESCC patients, 689 healthy control subjects and 347 immigrants of Linzhou living in Changzhi by using enzyme-linked immunosorbent assay. RESULTS: The plasma riboflavin levels in patients with ESCC were significantly lower than those in the healthy controls and immigrants of Linzhou living in Changzhi [(731.69 ± 330.67) µg/L vs (1090.43 ± 445.08) µg/L, (731.69 ± 330.67) µg/L vs (897.58 ± 177.78) µg/L, respectively, all P < 0.05], and the plasma riboflavin levels of the healthy controls were higher than those in the immigrants of Linzhou living in Changzhi (P < 0.05). CONCLUSION: Patients with ESCC have decreased plasma riboflavin levels as compared with the healthy controls and immigrants of Linzhou living in Changzhi, there exists a lack of riboflavin in ESCC patients, but the specific mechanism needs further study.

Functional SNPs in human C20orf54 gene influence susceptibility to esophageal squamous cell carcinoma.

OBJECTIVES: C20orf54, also known as a human riboflavin transporter 2 (RFT2), encodes an open reading frame protein RFT2 newly identified to play an important role in esophageal carcinogenesis by modulating riboflavin uptake. Missense cSNPs on exon 3,1172 C>A (T391M) and 1246A>G (I416V) have been suggested to modulate protein expression. The aim of present study was to explore the association of C20orf54 functional SNPs with susceptibility to esophageal squamous cell carcinoma (ESCC) in a northern Chinese population. METHODS: 240 patients with ESCC and 198 healthy individuals without overt cancer were chosen as our experimental subjects. Information about family address, sex, age, BMI, smoking and drinking habits and family history of cancer were collected. Blood samples were taken from all subjects and tumor tissues were freshly sampled from resected specimens. After DNA was extracted and amplified, the C20orf54 SNPs were sequenced by ABI 3730XL in BGI China. Frequencies were then calculated and associated with the collected suspicous risk factors. RESULTS: Drinking status, a family history of ESCC, blood type and BMI were found to have great influence on the risk of developing ESCC. Overall genotype frequencies of the RFT2 SNP 1172 C>A (rs3746803) and 1246A>G (rs3746802) in ESCC patients are significantly different from that in healthy controls (x2=13.10, P=0.001 and x2=7.97, P=0.019, respectively). For RFT2 rs3746803, C/T+T/T genotype did not show a relationship with the risk of ESCC (the age and gender adjusted OR=0.66, 95% CI=0.41-1.05) when using C/C genotype as the reference. For RFT2 rs3746802, the A/G +G/G genotype demonstrated a significantly decreased risk to the development of ESCC (the age and sex adjusted OR=0.53, 95% CI=0.34-0.84) with A/A as the reference. CONCLUSIONS: The present study suggests that the C20orf54 functional SNPs might be associated with a risk of ESCC development.