Baoqing Jia

RKIP expression associated with gastric cancer cell invasion and metastasis.

The purpose of this study was to analyze Raf kinase inhibitor protein (RKIP) expression in gastric cancer tissue, its correlation with gastric cancer clinical pathology, and its role in gastric cancer invasion and metastasis in order to provide experimental evidence for the potential biological therapy of this disease. Both immunohistochemistry and western blot analyses were used to test for RKIP expression in 55 cases of gastric cancer tissue and the adjacent gastric mucous membrane tissue. The correlations of RKIP expression with the onset, development, and clinical pathology of gastric cancer were analyzed. After transiently transfecting the human gastric cancer cell line MKN45 with a eukaryotic expression vector containing the full length RKIP cDNA, the changes in MKN45 cell invasiveness and metastatic ability were studied. Immunohistochemistry and western blot results revealed that the quantity of RKIP protein expressed in the gastric cancer tissues was significantly lower than that of the adjacent normal gastric mucous membrane tissues (pu2009<u20090.05). The quantity of RKIP protein expression was reduced (pu2009<u20090.05) as the gastric cancer cells differentiation decreased, the TNM stage increased, and the extent of invasion expanded. However, the expression of RKIP in the gastric cancer tissues was not associated with the patients age or gender (pu2009>u20090.05). By overexpressing RKIP in the human gastric cancer cell line MKN45 and through the use of a Transwell invasion chamber, we determined that RKIP overexpression significantly reduced both the invasiveness and metastatic ability of MKN45 cells (pu2009<u20090.05). Low or absent RKIP expression may be associated with the onset and development of gastric cancer and its ability to invade and metastasize.

Overexpression of ZEB1 associated with metastasis and invasion in patients with gastric carcinoma

The aim of this study was to investigate the expression of ZEB1 in gastric carcinoma, its correlation with the clinicopathology of gastric carcinoma, and the role of ZEB1 in invasion and metastasis in gastric carcinoma. ZEB1 expression was analyzed by immunohistochemistry and Western blot in 45 gastric carcinoma tissue samples that contained the adjacent gastric mucosa. The correlation between ZEB1 expression, the occurrence and development of gastric cancer, and clinical pathology was investigated. ZEB1 expression in the human gastric carcinoma cell line AGS was downregulated by RNA interference, and changes in ZEB1 expression corresponded with changes in the invasive and metastatic ability of AGS cells. Immunohistochemistry revealed that ZEB1 protein expression in gastric carcinoma tissues was significantly higher than in normal gastric mucosa tissues (pxa0<xa00.001). A lower degree of differentiation of gastric cancer (pxa0=xa00.009), a higher TNM (tumor, node, and metastasis) stage (pxa0=xa00.010), and a larger scope of invasion were correlated with higher expression of ZEB1 (pxa0=xa00.041, 0.002). However, the expression of ZEB1 in gastric carcinoma tissue was independent of gender, age, and tumor size (pxa0>xa00.05). Western blot results also showed that ZEB1 protein expression was significantly higher in gastric carcinoma tissue than in the adjacent normal gastric mucosa tissue (pxa0=xa00.008). A lower degree of differentiation of the gastric carcinoma correlated with a higher TNM stage, and a larger scope of invasion correlated with increased ZEB1 expression (pxa0=xa00.023). Transfection of ZEB1 siRNA in AGS cells significantly decreased the expression level of ZEB1 protein (pxa0=xa00.035). Furthermore, the number of cells that could pass through the Transwell chamber was significantly lower in the transfected group than in the non-transfected control group (pxa0=xa00.039), indicating that the suppression of ZEB1 expression could significantly reduce the invasive and metastatic ability of AGS cells (pxa0=xa00.005). Concluding, in gastric carcinoma tissue, overexpression of ZEB1 may be related to the occurrence and development as well as invasion and metastasis of gastric carcinoma.

Expression of PEBP4 protein correlates with the invasion and metastasis of colorectal cancer

This study aimed to investigate the expression of PEBP4 protein in colorectal carcinoma tissues and its correlation with the clinical pathology of colorectal cancer and to investigate the relationship between PEBP4 expression and the invasion and metastasis of colorectal cancer cells, which could provide an experimental basis for future biological treatments of human colorectal cancer. RT-PCR and western blot methods were applied to detect the mRNA and protein expressions, respectively, of PEBP4 in colorectal cancer tissues and normal pericarcinoma tissues, and their correlations with the tumorigenesis and development of colorectal cancer, as well as its clinical pathology, were analyzed. Using the RNA interference technology, the expression of PEBP4 was knocked down in the human colorectal cancer cell HCT116, and the changes of the invasion capability of HCT116 were monitored. The positive mRNA expression rate of PEBP4 in colorectal cancer tissue was significantly higher than that in the normal pericarcinoma tissue (pu2009<u20090.05). Also, the positive expression rate in the cancer tissues from patients with positive lymph node and distant metastasis was significantly higher than that from the patients negative for lymph node and distant metastasis (pu2009<u20090.05). The positive expression rate of PEBP4 in the cancer tissues from the patients in early stages (I, II) was significantly lower than the expression rate in patients in advanced stages (III, IV) (pu2009<u20090.05). A lower degree of differentiation in colorectal cancer corresponded to a higher positive mRNA expression rate of PEBP4 (pu2009<u20090.05). However, this was independent of the patient’s gender, age, and tumor size (pu2009>u20090.05). In colorectal cancer tissue, the expression of PEBP4 protein was consistent with its mRNA. Namely, PEBP4 protein expression in colorectal cancer tissues was significantly higher than that in the normal pericarcinoma tissues (pu2009<u20090.05), the expression in the cancer tissues from the patients with positive lymph node and distant metastasis was significantly higher than that from the patients who were negative for these metastases (pu2009<u20090.05), and a lower degree of differentiation in colorectal cancer corresponded to a higher TNM staging along with a higher PEBP4 protein expression (pu2009<u20090.05). After HCT116 cells transfected with PEBP4 siRNA, they showed a significantly lower expression level of PEBP4 protein (pu2009<u20090.05), and the number of cells that passed through the Transwell chamber was significantly lower compared to the non-transfected or the transfected controls (pu2009<u20090.05). The over-expression of PEBP4 protein may be related to the tumorigenesis, development, metastasis, and invasion of colorectal cancer.

RKIP suppresses gastric cancer cell proliferation and invasion and enhances apoptosis regulated by microRNA-224.

The purposes of this study were to determine the expression profile of Raf kinase inhibitor protein (RKIP) in human gastric cancer cells and its effect on the biological characteristics of SGC-7901 cell lines, to examine the modulatory effect of microRNA-224 (miR-224) on RKIP. The research will provide novel strategies for gastric cancer treatment in the future. Quantitative real-time reverse transcription PCR (qRT-PCR) was employed to determine the expression profile of RKIP in gastric cancer cell lines (SGC-7901, MGC80-3, and MKN45). A eukaryotic expression vector, pcDNA3.1-RKIP, was constructed and transfected into SGC-7901 cells. Changes in RKIP protein expression were examined by Western blot assays, and the effect of RKIP overexpression on SCG-7901 cell viability was determined by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-diphenytetrazoliumromide (MTT) assays. The effect of RKIP overexpression on SGC-7901 cell proliferation and apoptosis was analyzed by flow cytometry and that on the migration of SGC-7901 cells was investigated by Transwell migration assays. RKIP was identified to be a regulatory target gene of miR-224 using a luciferase reporter gene system, and the effect of miR-224 on intracellular RKIP protein expression was examined by Western blot assays. The regulatory effect of miR-224 on the biological characteristics of RKIP was investigated by MTT, flow cytometry, and Transwell invasion chamber assays. The expression of RKIP in gastric cancer cells was decreased significantly in comparison to that of normal gastric mucosal epithelial cells (GES-1) (pu2009<u20090.01), as demonstrated by qRT-PCR assays. Compared with the control group, the up-regulation of RKIP intracellular expression was observed in SGC-7901 cells after transfection of pcDNA3.1-RKIP for 48xa0h (pu2009<u20090.01). There were significant decreases in cell viability and the S-phase fraction (pu2009<u20090.05), concomitant with a significant increase in apoptosis (pu2009<u20090.01), as well as a significant reduction in cells migrating through Transwell chambers (pu2009<u20090.05), as shown by MTT, flow cytometry, and Transwell invasion chamber assays. A significant decrease in luciferase activities in cells transfected with a miR-224 mimic was observed compared with that of the control group (pu2009<u20090.05), as suggested by the luciferase reporter gene system. As shown by Western blot assays, there was a significant decrease in RKIP expression in SGC-7901 cells transfected with the miR-224 mimic for 48xa0h compared with the control group (pu2009<u20090.05). As shown by MTT, flow cytometry, and Transwell invasion chamber assays, the changes in biological characteristics induced by RKIP overexpression could be suppressed in SGC-7901 cells after transfection of the miR-224 mimic. In conclusion, the down-regulation of RKIP expression was observed in human gastric cell lines, and miR-224 could negatively regulate the expression and biological characteristics of RKIP, contributing to suppress the proliferation and invasion of gastric cells.

RKIP inhibits gastric cancer cell survival and invasion by regulating the expression of HMGA2 and OPN

The objective of this study was to explore the mechanism via which Raf kinase inhibitor protein (RKIP) suppresses the invasion of gastric cancer cells and promote apoptosis, with an attempt to provide evidences for the application of RKIP in treating gastric cancer. The recombinant plasmid pcDNA3.1-RKIP or RKIP-shRNA was transfected into the gastric cancer cell line SGC-7901 using liposome. Then, the messenger RNA (mRNA) and protein expressions of RKIP, HMGA2, and OPN were detected using qPCR and Western blotting. The effects of HMGA2 on the proliferation, apoptosis, and invasion of SGC-7901 cells were detected using flow cytometry and Transwell assay. To further explore the regulatory effect of PKIP on the biological activities of HMGA2, we over-expressed or knock down RKIP and HMGA2 simultaneously and detected its effects on the proliferation, apoptosis, and invasion of SGC-7901 cells. As shown by qPCR and Western blotting, after over-expression of RKIP in SGC-7901 cells, the mRNA and protein expressions of RKIP significantly increased (Pu2009<u20090.01), whereas the mRNA and protein expressions of HMGA2 and OPN significantly decreased (Pu2009<u20090.01). In contrast, the transfection of RKIP-shRNA in the SGC-7901 cells resulted in opposite results. After over-expression of HMGA2 in SGC-7901 cells, the protein expression of HMGA2 significantly increased (Pu2009<u20090.01); however, it significantly decreased after the transfection of HMGA2-shRNA (Pu2009<u20090.01). As shown by Transwell assay and flow cytometry, After the over-expression of HMGA2 in SGC-7901 cells, the (G2u2009+u2009S) phase fraction significantly increased (Pu2009<u20090.01); also, the percentage of the apoptotic cells significantly declined (Pu2009<u20090.05) and the number of invasive cells significantly increased (Pu2009<u20090.05). However, the interference of the expression of HMGA2 resulted in opposite results. The simultaneous over-expression of RKIP and HMGA2 in SGC-7901 cells or the simultaneous interference of RKIP and HMGA2 showed no significant difference with the control group in terms of (G2u2009+u2009S) phase fraction, percentage of apoptotic cells, and number of invasive cells (Pu2009>u20090.05). In conclusion, RKIP can inhibit the survival and invasion of gastric cancer cells and promote apoptosis, possibly by regulating the expression of HMGA2 or OPN.

Mll3 genetic variants affect risk of gastric cancer in the chinese han population.

It is reported that the expression level of MLL3 in gastric cancer tissue highly correlates with tumor progression. However, whether MLL3 genetic variants are associated with the risk of gastric cancer remains unclear. In this study, we conducted a genotyping analysis for MLL3 in 314 cases of gastric cancer and 322 controls from the Chinese Han population. 4 SNPs (rs6943984, rs4725443, rs3800836, rs6464211) were selected for the present analysis. We found 2 SNPs (rs6943984, rs4725443) of MLL3 gene were significantly associated with the risk of gastric cancer : the rs6943984 with the minor allele A and rs4725443 with the minor allele C revealed strong associations with increased gastric cancer risk [P <0.001, OR=1.97, 95% CI=1.48~2.64 and P <0.001, OR = 2.23, 95% CI = 1.54~3.24]. Haplotype analysis of the four SNPs showed that haplotype A-T-A-C, G-T-G-C, and G-C-A-C increased the risk of gastric cancer (P <0.001, P=0.18, and P<0.001, respectively), while haplotype G-T-A-C significantly reduced the risk of gastric cancer (P <0.001). We concluded that MLL3 variants are significantly associated with gastric cancer risk. Our results for the first time provided new insight into susceptibility factors of MLL3 gene variants in carcinogenesis of gastric cancer of the Chinese Han population.

An updated meta-analysis of the association between ADIPOQ rs2241766 polymorphism and colorectal cancer

Adiponectin (ADIPOQ) is a cytokine produced by adipose tissue involved in carcinogenesis. ADIPOQ SNP rs2241766 has been extensively studied in colorectal cancer (CRC) community with contentious and conflicting conclusions. The objective of this study was to comprehensively assess the association between SNP rs2241766 and CRC risk. PubMed, Embase, CNKI, as well as the references of the retrieved articles were searched to identify the eligible studies for this meta-analysis. Odds ratios (ORs) and 95xa0% confidence intervals (CIs) were used to assess the association. We also examined the heterogeneity and publication bias and performed sensitivity analyses. Seven studies with 2,414 cases and 2,796 controls together did not show any significant association between SNP rs2241766 and CRC risk. Subgroup analyses by ethnicity and sample size also failed to provide statistically significant evidence. This meta-analysis demonstrates that ADIPOQ SNP rs2241766 may not represent as an effect modifier for the risk of CRC.

Molecular Epidemiologic Correlation Analysis Between Caspase3 Gene Polymorphism and Gastric Cancer Susceptibility

The objective was to analyze the relation between gastric cancer susceptibility and gene polymorphism, providing a reference for epidemiologic research of gastric cancer etiology. Two hundred and eighty gastric cancer cases were selected, and 280 healthy cases with the same gender, age (±5), and residence place were selected as control group, with proportion of 1:1. Tag single nucleotide polymorphism was used for screening polymorphism of caspase3, which was combined with logistic regression model and multi-point joint analysis to analyze relation between different genotypes and gastric susceptibility. In analysis of gene polymorphism of caspase3 intrinsic apoptotic pathway and gastric cancer susceptibility, polymorphism of CASP3 rs4647693, CASP3 rs12108497 and CASP3 rs4647610 increased gastric cancer risk (rs4647693: ORGA 1.61, 95xa0% CI 1.06–2.28; rs12108497: ORTC 1.55, 95xa0% CI 1.09–2.18; ORCC 2.45, 95xa0% CI 1.08–4.16; rs4647610: ORAG 1.71, 95xa0% CI 1.14–2.31; ORGG 1.60, 95xa0% CI 1.23–2.34). Gastric cancer risk of haplotype AGGC carrier was significantly higher than that of haplotype GGAT as control (OR 1.44, 95xa0% CI 1.07–2.19). Gene polymorphism and haplotype of caspase3 can increase gastric cancer risk. However, it still needs to be verified by a large-sample and multicenter epidemiologic research.

RKIP promotes cisplatin-induced gastric cancer cell death through NF-κB/Snail pathway.

The objectives of this study were to explore the expression profiles of Raf kinase inhibitor protein (RKIP) in human gastric cancer cell line (SGC-7901) and cisplatin-resistant cell line (SGC-7901/DDP) and investigate the role of RKIP in the sensitivity of human gastric cancer cells to cisplatin and its signaling pathways, with an attempt to identify new approaches and strategies for the management of gastric cancer. The human gastric cancer cell line (SGC-7901) and cisplatin-resistant cell line (SGC-7901/DDP) were separately cultured in vitro. The expression profiles of RKIP in these two cell lines were detected by Western blotting. Forty-eight hours after the transfection of RKIP siRNA in SGC-7901 cells, the change of RKIP expression in the cells was detected using Western blotting, and the change of cell viability after the interference of RKIP expression was determined using 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di-phenytetrazoliumromide (MTT) method. The effect of the ectopic expression of RKIP on the cisplatin-induced viability of gastric cancer cell was detected using MTT method. The effect of the ectopic expression of RKIP on the cisplatin-induced apoptosis of gastric cancer cell was detected using flow cytometry after having been double stained with Annexin V/PI. The effect of the ectopic expression of RKIP on the NF-κB and Snail expressions in cisplatin-induced gastric cancer cells was detected using Western blotting. As shown by the Western blotting, the expression of RKIP in SGC-7901/DDP cells significantly decreased when compared with that in SGC-7901 cells (Pu2009<u20090.05). Compared with the control group, the expression of RKIP in SGC-7901 cells significantly decreased 48xa0h after the transfection of RKIP siRNA (Pu2009<u20090.01). After the SGC-7901 cells were transfected with RKIP siRNA, the cell viability was significantly increased (Pu2009<u20090.05); after the SGC-7901/DDP cells were transfected with RKIP recombinant plasmid, the cell viability was significantly decreased (Pu2009<u20090.05). After the RKIP expression was suppressed in the cisplatin-treated SGC-7901 cells, the cell viability significantly increased (Pu2009<u20090.05), and the amount of apoptotic cells significantly decreased (Pu2009<u20090.05). In contrast, after the RKIP overexpression in the cisplatin-treated SGC-7901/DDP cells, the cell viability significantly decreased (Pu2009<u20090.05), and the amount of apoptotic cells significantly increased (Pu2009<u20090.05). The suppression of RKIP expression in SGC-7901 cells could significantly promote the increase of NF-κB expression (Pu2009<u20090.05); in contrast, the increased expression of RKIP in SGC-7901/DDP cells significantly inhibited the expression of Snail (Pu2009<u20090.05). The expression of RKIP is downregulated in cisplatin-resistant cell line (SGC-7901/DDP). The overexpression of RKIP can enhance the sensitivity of human gastric cancer cells to cisplatin, which may be achieved via the NF-κB/Snail signaling pathway.

A 5-serum miRNA panel for the early detection of colorectal cancer

Objective The study aimed to screen microRNAs (miRNAs) that can be used for the early detection of colorectal cancer (CRC) based on differential expression of miRNA in serum. Materials and methods A three-stage study was designed with a total of 217 CRCs, 168 colorectal adenomas (CRAs), and 190 healthy controls (HCs). A quantitative reverse transcription polymerase chain reaction was performed in three stages. We screened 528 miRNA expression profiles in the sera of 40 patients (CRC n=20, CRA n=10, and HC n=10) for candidate miRNAs, then 210 serum samples (CRC n=90, CRA n=60, and HC n=60) were used for screening of candidate miRNAs. Three hundred and twenty-five independent individual samples (CRC n=107, CRA n=98, and HC n=120) were used to validate the most differentially-expressed miRNAs in the screening stage, and binary logistic regression was used in the validation stage. A receiver operating characteristic curve was drawn to evaluate the diagnostic accuracy. Results A 5-serum miRNA panel (miRNA-1246, miRNA-202-3p, miRNA-21-3p, miRNA-1229-3p, and miRNA-532-3p) effectively distinguished CRCs from HCs with 91.6% sensitivity and 91.7% specificity. The area under the curve (AUC) was 0.960 (95% confidence interval [CI]: 0.937–0.983). In addition, the panel also accurately distinguished CRCs from CRAs with 94.4% sensitivity and 84.7% specificity. The AUC was 0.951 (95% CI: 0.922–0.980). Conclusion Our 5-serum miRNA panel accurately distinguished CRCs from CRAs and HCs with high sensitivity and specificity. The 5-serum miRNA panel may be a promising prospect for application as a nonintrusive and inexpensive method for the early detection of CRC.