Interleukin-4 receptor -3223T→C polymorphism is associated with increased gastric adenocarcinoma risk.

BACKGROUND: Gastric cancer remains one of the most common types of cancer worldwide, with a large geographical variation in incidence and mortality rates. Cytokine polymorphisms are the most studied host polymorphisms and are associated with an increased risk of stomach cancer in many regions, but have not been studied extensively in Eastern European populations. OBJECTIVE: To investigate the potential association between five cytokine promoter polymorphisms (interleukin [IL] 1b -511C→T [rs16944], IL-4 receptor [IL-4R] -3223C→T [rs2057768], IL-8 -251T→A [rs4073], IL-10 -1082A→G [rs1800896] and tumour necrosis factor-alpha -308G→A [rs1800629]) and susceptibility to gastric adenocarcinoma in a Romanian population. METHODS: A total of 347 subjects, consisting of 105 patients with gastric adenocarcinoma and 242 controls, were included. All cytokine polymorphisms were genotyped using allele-specific, commercially available probes. Hardy-Weinberg equilibrium in both groups was analyzed using the chi squared test, and the relationship between targeted polymorphisms and the risk of gastric cancer was estimated using OR and 95% CI. RESULTS: A significant association between the IL-4R -3223C→T polymorphism and risk of gastric cancer was found. Carriers of the IL-4R -3223TT genotype were at a 2.5-fold increased risk for gastric cancer (OR 2.51 [95% CI 1.08 to 5.84]; P=0.041). Moreover, the presence of the IL-4R -3223TT genotype was associated with an increased risk of noncardia gastric adenocarcinoma (OR 3.08 [95% CI 1.25 to 7.58]; P=0.023). No associations were found among the other polymorphisms. CONCLUSION: The results suggest that the IL-4R -3223C→T polymorphism may increase the risk of gastric adenocarcinoma, mainly for the noncardia type, in the Romanian population.

Histochemical and immunohistochemical evidence of tumor heterogeneity in colorectal cancer.

INTRODUCTION: Intratumoral heterogeneity implies the existence of differences between tumor cells, which can best be shown by histochemical and immunohistochemical techniques. The histological study is a mandatory step in any research aimed at characterizing tumor heterogeneity. Immunohistochemistry (IHC) also plays an important role in the differentiation of tumor types, assessing aggressiveness. MATERIALS AND METHODS: Investigated group consisted of 50 patients with colorectal adenocarcinoma, for each were recorded clinicopathological data and harvested samples intraoperatively, which were included in paraffin blocks. We perform Hematoxylin-Eosin staining for histological grade and other indices. IHC study used Avidin-Biotin-Peroxidase (ABC), with the markers: CK7, CK20, MUC1, MUC2, Ki-67, PCNA, p53, KRAS, BCL2, PTEN, EGFR. The resulting data were analyzed by statistical methods. RESULTS: Most of colorectal adenocarcinoma studied had no special histological features and had G2 grade. IHC detected in most cases the CK20+÷CK7- phenotype (78%) and MUC1 (74%) protein expression. The proliferation markers (Ki-67 and PCNA) were present in all tumor mass with a variable index, which shows high intratumoral heterogeneity, but p53 and KRAS were distributed more uniformly, showing low intratumoral heterogeneity. PTEN was expressed nuclearly in 86% of the cases and EGFR in 42%. CONCLUSIONS: The expression profiles of cytokeratins and mucins in the colorectal adenocarcinomas are useful in defining tumor phenotypes with different prognosis and therapy. We found a significant positive correlation between KRAS protein expression and BCL2 and TP53 expression. The study demonstrated the intratumoral and intertumoral heterogeneity, expressed at phenotypic level.

c-abl and YWHAZ gene expression in gastric cancer.

This study aims to determine the gene expression for c-abl and YWHAZ in gastric cancer and the differences between the c-abl and YWHAZ gene expression inside the tumor versus healthy tissue (at the resection edges). This prospective study included 34 patients with gastric neoplasia, 21 men and 13 women, aged between 49 and 79 years (65.5 years median). After the surgical procedure, in these cases, we collected two tissue samples: one sample was obtained from inside the tumoral tissue and another sample from the gastric tissue, which was identified as normal apparently, as far as possible from the tumor (resection edge). For determining the c-abl and YWHAZ gene expression, we used the quantitative real-time polymerase chain reaction. Regarding the c-abl gene expression in gastric cancer, c-abl expression was identified as lower inside tumor cells comparing to the normal gastric tissue (resection limit). This difference of gene expression emphasize the role of the c-abl gene in normal tissue growth and the involvement in apoptosis induction when alteration of DNA occurs, as a result to different agents actions as stress, ionizing radiations. The loss of expression or even the down-regulation of the c-abl is a fundamental event that leads to genesis and progression of tumors. No significant differences of the YWHAZ gene expression between the tumoral and normal gastric tissue probes were recorded in our study.

VEGF-A and VEGF-B mRNA expression in gastro-oesophageal cancers.

INTRODUCTION: Angiogenesis is essential for the local growth, invasion and metastasis of the tumours. Vascular endothelial growth factors (VEGFs) play a crucial role in tumour angiogenesis. The aim of our study was to quantify the expression of several VEGF family molecules in human gastro-oesophageal cancers and to analyse possible correlations between genes expression and clinico-pathological features. MATERIALS AND METHODS: Gene expression was quantified in 43 gastro-oesophageal paired samples using qRT-PCR with TaqMan probes specific to VEGF-A, including soluble transcript variants and VEGF-B genes. RESULTS: VEGF-A, including the studied splice variants and VEGF-B mRNAs were expressed in both tumour and peritumour mucosa. The expression of VEGF-A and its isoforms was higher in tumour compared with paired peritumour mucosa, while no significant difference was observed in VEGF-B expression. VEGF-A expression tended to correlate with tumour invasion. CONCLUSION: VEGF-A has a tendency to over-express in gastro-oesophageal cancers, while VEGF-B does not seem involved in these tumours. Further studies are required to establish the utility of anti-VEGF-A therapy and to find biomarkers for pathogenesis or response to therapy in gastro-oesophageal tumours.

MMR gene expression pattern in sporadic colorectal cancer.

BACKGROUND AND AIMS: Colorectal carcinoma is the second leading cause of death by cancer in Europe as its incidence increases with life span. Continuing research to detect new highly sensitive and specific noninvasive biomarkers is essential. The aim of this study was to compare 9 mismatching repair (MMR) genes activation levels in normal, polyp and malignant tissues in order to detect a MMR gene expression pattern in sporadic colorectal malignant pathology. METHODS: MMR mRNA levels were evaluated in tumor-normal tissue paired samples and polyps collected from 29 patients undergoing standard surgical procedures with curative intention. Real-Time quantitative Reverse Transcription PCR (qRT PCR) with TaqMan probes specific to ANKRD17, EXO1, MLH1, MLH3, MSH2, MSH3, MSH4, MSH5, MSH6 gene transcripts were used. RESULTS: The general tendency observed was a lower mRNA level of MMR genes in tumor samples compared with the normal tissue, with the exception of EXO1 gene. The number of patients that showed a higher expression of MMR genes in normal tissue was significantly greater than the number of patients that showed a higher expression inside the tumor (p=0.0024). ANKRD17 mRNA levels were higher in normal tissue than in tumor for 16 cases, by contrast with only 6 cases of higher mRNA levels in tumor. CONCLUSIONS: ANKRD17 mRNA appears to be the most sensitive target and may have a potential value as an additional marker for the existing multitarget assay panel for colorectal cancer detection.