Promoter CpG island hypermethylation and down regulation of XRCC1 gene can augment in the gastric carcinogenesis events.

Gastric cancer (GC) is a multistep process characterized by a gradual accumulation of genetic and epigenetic alterations in genes at various stages of progression. Epigenetic alterations like DNA methylation play an important role in cancer and may serve as a biomarker for cancer. The present study was aimed to investigate the promoter hypermethylation, expression profile, and Arg399Gln gene polymorphism of DNA repair gene XRCC1 (X-ray repair cross complimentary group I) in GC patients. A total of 60 histopathologically confirmed GC subjects were recruited in the study. Information on various dietary, lifestyle and environmental factors was obtained in face-to-face interviews using a structured questionnaire from each subject. Tissue samples were taken along with adjacent non-cancerous tissues for analysis. Promoter methylation status and expression of XRCC1 gene was evaluated using MS-PCR and western blotting respectively; while as Arg399Gln polymorphism was analyzed by PCR-RFLP. We found that the XRCC1 gene promoter of 38.3% cancerous tissues were methylated compared to 13.3% of adjacent normal tissues. The promoter hypermethylation status of the gene was found to be significantly associated with the loss of protein expression (P < 0.0001, OR = 14.63; 95% CI 4.01-53.43). However, we did not find any significant association of polymorphism of XRCC1 Arg399Gln with promoter methylation or protein expression. Further, comparison of methylation status and protein expression with clinical parameters like age, smoking status, etc. was also not significant (P > 0.05). The present study indicates that XRCC1 undergoes aberrant promoter hypermethylation with subsequent loss of protein expression in gastric cancer.

Outcome of hepatitis C patients in a community with predominant genotype 3 with standard-of-care treatment before and after advent of direct-acting antivirals: A retrospective-cum-prospective study.

BACKGROUND AND OBJECTIVE: Chronic hepatitis, cirrhosis, and hepatocellular carcinoma are mainly caused by hepatitis C infection. It is a worldwide predominant pathogen and is one of the main causes of healthcare problem in Asia. In the last few decades, there has been a considerable change in the treatment regimen for hepatitis C virus. The objective of this research was to relate the treatment response with sustained viral response in various therapies which have been the standard of care from time to time. MATERIALS AND METHODS: This hospital-based, retrospective-cum-prospective research span over a period of 2 years; we enrolled hepatitis C patients who attended the Department of Gastroenterology and Hepatology, Government Medical College, Srinagar, since June 2015 till May 2017. Subsequently, the database was prepared, containing all the relevant information about these patients. CONCLUSIONS: (i) In retrospective group: The overall efficacy (sustained viral response at 24 weeks [SVR-24]) of pegylated interferon a2a and ribavirin regimen was 90.96%. (ii) In prospective group: The efficacy (SVR) of different regimens was found to be as: sofosbuvir + ribavirin + daclatasvir (SVR-24, 83.33%); sofosbuvir + ribavirin (SVR-12, 94.57%); and sofosbuvir + daclatasvir (SVR-12, 98.00%).

Impact of catechol-O-methyltransferase gene variants on methylation status of P16 and MGMT genes and their downregulation in colorectal cancer.

Globally, colorectal cancer (CRC) is the third most commonly diagnosed cancer in males and the second most commonly diagnosed cancer in females, with 1.4 million new cases and almost 694 000 deaths estimated to have occurred in 2012. The development and progression of CRC is dictated by a series of alterations in diverse genes mostly proto-oncogenes and tumor suppressor genes. In this dreadful disease disturbances different from mutations called as epigenetic regulations are also taken into consideration and are thoroughly investigated. The present study was designed to analyze the promoter hypermethylation of CpG (cytosine, followed by guanine nucleotide) islands of cyclin-dependent kinase inhibitor 2A (P16) and O-methylguanine-DNA methyltransferase (MGMT) genes and its subsequent effect on the protein expression in CRC. The impact of the common functional polymorphism of the catechol-O-methyltransferase (COMT) gene, Val158Met, on promoter hypermethylation of P16 and MGMT genes in CRC was also investigated. The study included 200 CRC cases and equal numbers of normal samples. DNA was extracted using the kit method and methylation specific-PCR was performed for analysis of the promoter hypermethylation status. Total protein was isolated form all CRC cases and western blotting was performed for P16 and MGMT proteins. The COMT Val158Met polymorphism was analyzed by a PCR-restriction fragment length polymorphism assay. Epigenetic analysis showed that unlike other high-risk regions, the Kashmiri population has a different promoter hypermethylation profile of both P16 and MGMT genes, with frequent and significant promoter hypermethylation of both in CRC. The frequency of promoter hypermethylation of both genes was significantly higher in males and was insignificantly found to be higher in stage III/IV. The degree of P16 and MGMT promoter hypermethylation increased significantly with increasing severity of the lesion. We also found a significant correlation between P16 and MGMT promoter hypermethylation and loss of protein expression in CRC. A significant association was found between COMT polymorphism (homozygous variant) and P16 methylation status. Similar results were also found for MGMT hypermethylated cases.

DNA Repair Gene XRCC1 and XPD Polymorphisms and Gastric Cancer Risk: A Case-Control Study Outcome from Kashmir, India.

Coding polymorphisms in several DNA repair genes have been reported to affect the DNA repair capacity and are associated with genetic susceptibility to many human cancers, including gastric cancer. An understanding of these DNA repair gene polymorphisms might assess not only the risk of humans exposed to environmental carcinogens but also their responses to different therapeutical approaches, which target the DNA repair pathway. In the present study, polymorphic variants of two DNA repair genes, XRCC1 Arg399Gln and XPD Lys751Gln, were chosen to be studied in association with gastric cancer susceptibility in the Kashmiri population. A total of 180 confirmed cases of gastric cancer (GC) and 200 hospital-based controls from Government Shri Maharaja Hari Singh Hospital, Srinagar, were included in the study. The genotyping for XRCC1 and XPD genes was carried out by polymerase chain reaction-restriction fragment length polymorphism. We found that tobacco smoking is strongly associated with GC risk (OR = 25.65; 95% CI: 5.49-119.7). However, we did not find any association of polymorphism of XRCC1 Arg399Gln (OR = 1.56; 95% CI: 0.32-7.82) and XPD Lys751Gln (OR = 0.46; CI: 0.10-2.19) with GC risk in the study population. The combination of genotypes and gender stratification of XRCC1 and XPD genotypic frequency did not change the results. Consumption of large volumes of salt tea was also not associated with gastric cancer risk. Polymorphic variants of XRCC1 Arg399Gln and XPD Lys751Gln are not associated with the risk of gastric cancer in the Kashmiri population. However, replicative studies with larger sample size are needed to substantiate the findings.

Psychiatric Co-morbidity in Patients With Irritable Bowel Syndrome at a Tertiary Care Center in Northern India.

BACKGROUND/AIMS: Irritable bowel syndrome (IBS) is a chronic psycho-physiological disorder. It is considered to be the most common functional gastrointestinal disorder, and about 50-90% of IBS patients have associated psychiatric co-morbidity. We aimed to study psychiatric co-morbidities in patients with IBS visiting a tertiary care center. METHODS: This was a cross-sectional case-control study conducted over a duration of one and a half years from January 2014 to July 2015. Patients were selected from the out-patient department of gastroenterology. About 160 patients with IBS who fulfilled the inclusion criteria and who gave written informed consent were selected as study cases. The healthy attendants of cases were selected as controls. A total of 200 controls were selected. Rome-III criteria were used to diagnose IBS. For diagnosing psychiatric disorders, we used the Mini International Neuropsychiatric Interview Schedule Plus. RESULTS: Mean age of our cases and controls was 39.7 ± 11.4 and 37.7 ± 9.6 years, respectively. Females outnumbered males in our cases as well as their controls by a ratio of 2:1 approximately. Psychiatric disorders were seen in 84.4% of IBS patients as compared to 41.5% in controls. Major psychiatric disorders seen in our patients were generalized anxiety disorders (30.0%) and depression (28.0%). CONCLUSIONS: The majority of patients with IBS who present to a tertiary care center have co-morbid psychiatric disorders. We need to screen these patients for such co-morbidities and develop a holistic approach for better outcome in such cases.

Promoter Hypermethylation and Its Impact on Expression of MGMT Gene in the GIT Malignant Patients of Kashmiri Origin.

Epigenetic alterations, in addition to multiple gene abnormalities, are involved in the genesis and progression of human cancers. Gastrointestinal tract (GIT) cancer is a major medical and economic burden worldwide. Aberrant methylation of CpG islands within promoter regions is associated with transcriptional inactivation of various tumor suppressor genes. Although a number of cancer-associated genes have been found to be hypermethylated in GIT cancer, valuable methylation markers for early diagnosis and prognostic evaluation of this cancer remain largely unknown. O6-methyguanine DNA methyltransferase (MGMT) is a DNA-repair gene that removes mutagenic and cytotoxic adducts from the O6 position of guanine induced by alkylating agents. MGMT promoter hypermethylation and reduced expression have been found in some primary human carcinomas. We studied DNA methylation of CpG islands of the MGMT gene and its relation with MGMT protein expression in human GIT carcinomas. A total of 210 GIT tumor samples and 90 adjacent normal tissues were analyzed for MGMT promoter methylation by methylation-specific polymerase chain reaction after bisulfite modification of DNA and same samples were analyzed for MGMT protein expression by Western blotting. The methylation frequencies of MGMT gene promoter were 41.4%, 34.2%, and 44.2% in stomach, esophageal, and colorectal cancer cases while as 16.6, 13.3, and 13.3 in respective controls. MGMT protein was found downregulated in controls of all GIT. The results suggest that methylation at CpG islands of MGMT may be responsible for the downregulation of MGMT protein expression in GIT cancers.

Association of Pro12Ala Polymorphism of Peroxisome Proliferator-Activated Receptor gamma 2 (PPARγ2) Gene with Type 2 Diabetes Mellitus in Ethnic Kashmiri Population.

Type 2 diabetes mellitus (T2DM) is characterized by chronic hyperglycemia associated with insulin resistance and relative insulin deficiency. T2DM is believed to be attributable to the combined effect of genetic and environmental factors. Peroxisome proliferator-activated receptor gamma 2 (PPARγ2) is one of the main candidate genes that are implicated in T2DM. A common proline 12 alanine (Pro12Ala) polymorphism in PPARγ2 has been shown to be associated with T2DM. The aim of this work was to investigate the possible role of PPARγ2 gene polymorphism, as a genetic risk factor for T2DM. The study comprised 200 ethnic unrelated subjects (100 T2DM patients and 100 controls). PCR-RFLP technique was used for genotyping analysis. The frequency of the Pro allele was 79 and 91.5 % for controls and cases, respectively (P < 0.05; OR 3.2; 95 % CI 1.64-6.3). The Pro12Ala polymorphism was in Hardy-Weinberg equilibrium in both patients and controls (χ 2 = 0.13, P > 0.05). We found a significant association of Pro12Ala polymorphism of PPARγ2 gene with T2DM, however the genotypes showed statistically significant association only with few clinical parameters including body mass index, total cholesterol, and low-density lipoprotein (P < 0.05). The study signifies that Pro allele in PPARγ2 may be a genotypic risk factor that confers susceptibility to T2DM in ethnic Kashmiri population.

Evaluation of iron deficiency anaemia for gastrointestinal causes in patients without GI symptoms in high prevalent GI malignancy zones.

BACKGROUND AND STUDY AIMS: Gastric cancer is highly prevalent in Kashmir, as are lower gastrointestinal (LGI) malignancies. Colonic cancer, gastric cancer, and coeliac disease are the most important gastrointestinal (GI) causes of iron deficiency anaemia (IDA) worldwide. Approximately 9% of patients with IDA present with a suspicious lesion in the GI tract upon examination. However, the absence of GI symptoms and a possible lesion accounting for blood loss in IDA have not been studied in this zone with a high prevalence of GI malignancy. We aimed to examine IDA patients without GI symptoms to determine the most plausible cause of their blood loss. PATIENTS AND METHODS: A total of 100 patients with IDA and 250 control subjects without IDA and referred for gastrointestinal endoscopy were enrolled in a cross-sectional, comparative study. Patients presenting with a significant lesion proportionate to their anaemia in the upper GI tract were not examined further, if no further strong indications were present. RESULTS: Twenty-nine patients (29%) were found to have malignancy: 13 with gastric cancer and 16 with colonic malignancies. Other apparent causes of GI blood loss included peptic ulcer disease in 10 (10%) patients, haemorrhoids in 22 (25%), polyps in eight (three in the upper GI tract and five in the LGI tract), gastric erosions in eight (8%), and angiodysplasia, diverticulitis, and trichuriasis in two (2%) each. CONCLUSION: In light of the high incidence of GI malignancies in this patient group, a low threshold for GI screening as well as mass screening for IDA is needed.

Diminished expression of MGMT & RASSF1A genes in gastric cancer in ethnic population of Kashmir.

BACKGROUND: Cancer initiation and progression are accompanied by profound changes in DNA. DNA methylation that was the first epigenetic alterations identified in cancer. DNA hypermethylation at promoter sites is closely associated with down regulation of protein and as major participant in the development and progression of series of human tumors. Therefore we hypothesized that promoter hypermethylation of RASSF1A & MGMT gene could influence susceptibility to gastric cancer (GC) as well, and we conducted this study to test the hypothesis in Kashmiri population. METHODS: A hospital based case-control study; including 200 GC cases and 200 matched controls from patients who went surgical resection. Promoter hypermethylation was determined by Methylation Specific Polymerase chain reaction. The expression of MGMT & RASSF1A protein was examined by Western blotting technique. RESULTS: Frequency of promoter region hypermethylation of MGMT gene were 46.5% in cases and 5.5% in controls (P<0.05) while as in case of RASSF1A frequency was 44% in cases and 4.5% in controls (P<0.05). Further, frequency of hypermethylation of both genes was found predominant in males, aged and advanced pathological stage subjects. Loss of MGMT expression was found in 46.5% cases (P<0.05) while as loss of RASSF1A expression was found in 40.5% cases (P<0.05). In both genes a positive correlation was observed between promoter CpG island hypermethylation and down regulation of respective proteins. CONCLUSIONS: These findings indicate that promoter hypermethylation at CpG island may be responsible for reduction of expression at protein level which may be an initial event in carcinogenesis and the progression of GC.

Role of the VDR Bsm I and Apa I polymorphisms in the risk of colorectal cancer in Kashmir.

OBJECTIVE: A case-control study aiming to evaluate the relationship between Bsm I and Apa I restriction fragment gene polymorphisms and colorectal cancer (CRC) was carried out in Kashmir, including a total of 368 subjects (180 cases and 188 controls). METHODS: DNA samples extracted from the blood of the subjects were analyzed for 3' untranslated region (3' UTR) Apa I and Bsm I polymorphisms using restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR). RESULTS: A statistically significant 2.7-fold increased risk was observed in individuals found homozygous for the presence of the 'b' allele, in comparison to subjects homozygous for the 'B' allele (odds ratio (OR) 2.7, 95% confidence interval (CI) 1.49-4.86 (Bsm I)), and a statistically insignificant 2-fold increased risk was found among individuals with the 'aa' genotype, as compared to subjects with the 'AA' genotype (OR 2.017, 95% CI 0.86-4.7). Our study also yielded statistically significant results when the Apa I polymorphism was stratified by age (≤ 50 years) and dwelling area (rural area), and the Bsm I polymorphism by gender (male gender), suggesting a possible role of Apa I and Bsm I polymorphisms in the etiology of CRC in Kashmir. CONCLUSION: We conclude that Apa I and Bsm I single-nucleotide polymorphisms (SNPs) in the vitamin D receptor gene (VDR) might be associated with susceptibility to CRC among Kashmiris.

Association of a VDR gene polymorphism with risk of colorectal cancer in Kashmir.

Roles of the vitamin D receptor in etiology of cancers, including colorectal cancer, have been repeatedly stressed in different parts of the world. A case control study aimed to evaluate the relationship between the two was therefore initiated in Kashmir, known both for its increasing incidence of gastrointestinal cancers and deficiency of micro-nutrients especially vitamin D. The study included a total of 617 subjects (312 colorectal cancer cases and 305 controls), with sampling carried out over a period of 5 years. DNA samples from the blood of the subjects were analyzed for start codon Fok I VDR polymorphism. We obtained a 1.3 fold increased risk among individuals homozygous for f variants as compared to subjects homozygous for F allele (odds ratio OR 1.3, 95%CI, 0.861-1.65). Our study also showed statistically significant results when dwelling and tumor location characteristics were stratified with Fok I polymorphism, all of which suggests a possible role of Fok I polymorphism in the etiology of CRC in Kashmir.

A comparative overview of general risk factors associated with the incidence of colorectal cancer.

Cancers found in colorectal region remain largely localized to the large intestine and rectum. They are derived from the epithelium and are considered to be among the most frequently detected cancers. They are known to occur in approximately 5 % population of the Western world. After metastasis, a patient's 5-year postsurgical survival chances unfortunately fall from 90 to 10 % or even less. Adenocarcinoma, the most common cell type of colon cancer, alone constitutes 95 % of the cases. Lymphoma and squamous cell carcinoma can also be found in some cases. Because 5 % of persons are predisposed to development of colorectal cancer, this disease has often been addressed as an important public health issue. Factors that are known in particular to increase a person's risk to develop this cancer are as follows: an individual's age, dietary habits, any complaint of obesity, diabetes, previous history of cancer or intestinal polyps, personal habit of alcohol consumption and smoking, family history of colon cancer, race, sex, and ethnicity. Since the risk of colorectal cancer is increasing steadily in Kashmir, India, like in some other corners of Asia, exhaustive efforts are being made to find the association of above given and other risk factors with the development of this gastrointestinal tract cancer. Adoption of Western life style, diet mimicry, together with a habit of having physically inactive life style and consumption of red meat in particular can be blamed as being active players to a considerable extent.

The ECRG1 290Arg/Gln polymorphism is related to risk of esophageal squamous cell carcinoma in Kashmir.

ECRG1 (esophageal cancer related gene 1) is a novel candidate member of the tumor suppressor gene family previously found to be down regulated in human esophageal cancer (ESCC). So far no evidence regarding the role of the ECRG1 gene in this cancer has been reported from the Kashmir valley, located on the border of the high risk 'esophageal cancer belt'. A case control study was therefore carried out with genomic DNA from 165 newly diagnosed ESCC patients (cases) and 200 control subjects. DNA was analyzed for ECRG1 polymorphisms by RFLP PCR, gel electrophoresis and direct sequencing. A statistically significantly increased risk of ESCC was found to be associated with the ECRG1 Arg/Gln and Gln/Gln genotype occurrence compared to the Arg/Arg genotype (odds ratio (OR) 1.698, 95% confidence interval (CI) 1.112-2.593); P= 0.0138) was observed. Statistically significant results were also obtained between the ECRG1 polymorphism and histophathological grade, smoking, dysphagia, low fruit/vegetable intake and salt tea consumption.

Gastric cancer in kashmir.

Gastric cancer has been reported to be a highly prevalent malignancy in Kashmir, where together with esophageal cancer it accounts for more than 60% of all cancers, much higher than in other parts of the region. Particular life style habits like consumption of salted tea and tobacco smoking by hukkah, as well as Helicobacter pylori infection, are often mentioned in the context of risk factors. However, the majority of the population does not consume alcohol and the prevalence of H. pylori does not appear to explain the high incidence of gastric cancer in the population. Other prevalent habits of gastric cancer patients are presented here along with demographic and tumor details. In future, well designed studies of incidence rates (population based) are essential along with investigations of reported and suspected risk factors.