Methylation Status of CDH1 Gene in Gastric Biopsy Specimens and Its Association with H. Pylori Infection.

BACKGROUND: Helicobacter pylori (H. pylori) have been accepted as having an etiologic role in gastro-duodenal diseases as chronic gastritis, peptic ulcer, and gastric carcinoma. Methylation of CGI has been correlated with the tumorigenic process since it can inactivate tumor suppressor genes. CDH1 is a tumor suppressor gene that encodes the E-cadherin protein, which is preserving cell-cell connections. Early stages of gastric carcinogenesis may be affected by the promoter methylation-mediated inactivation of this gene. OBJECTIVE: This study aimed to investigate the methylation status of CDH1 using Methylation-Specific PCR (MSP) technique in clinical suspected patients with H. pylori infection who undergoing upper gastrointestinal endoscopy and correlated it with H. pylori detection by glmM PCR test. METHODS: Fifty gastric mucosal biopsies were selected from one hundred and five samples included in this study. The detection of H. pylori was performed with the PCR primers specific to glmM gene. Bisulfite modification was done and the methylation status of the CDH1 gene was detected using MSP reaction. RESULTS: H. pylori was detected in 36% (18/50) of study population using glmM gene PCR test, 89% (16/18) of H. pylori positive cases were CDH1 methylated  positive (chi-square, p-value=0.002). CDH1 methylation can be present in cancerous and noncancerous gastric mucosa, where 60% (18/30) of CDH1 methylation positive gastric mucosa showed gastritis as an endoscopy finding and gastric cancer in 6% (2/30). There was a significant correlation between and CDH1 methylation positive results and age group (P-value = 0.02). There was no significant correlation between CDH1 methylation positive results and participants gender (p-value=0.431) and clinical symptoms (all P-value > 0.05). CONCLUSION: This work suggested strong significance association between H. pylori infection and CDH1 methylation.

Intestinal parasitic infections among expatriate workers in various occupations in Sharjah, United Arab Emirates.

Intestinal parasitic infections are prevalent throughout many countries. This study aimed to determine the prevalence of intestinal parasite carriers among 21,347 expatriate workers, including food handlers and housemaids attending the public health center laboratory in Sharjah, UAE. Stool sample collection was performed throughout the period between January and December 2013. All samples were examined microscopically. Demographic data were also obtained and analyzed. Intestinal parasites were found in 3.3% (708/21,347) of the studied samples (single and multiple infections). Among positive samples, six hundred and eighty-three samples (96.5%) were positive for a single parasite: Giardia lamblia (257; 36.3%) and Entamoeba histolytica/Entamoeba dispar (220; 31.1%), respectively, whereas mono-infections with helminths accounted for 206 (29.1%) of the samples. Infection rates with single worms were: Ascaris lumbricoides (84; 11.9%), Hookworm (34; 4.8%), Trichuris trichiura (33; 4.7%), Taenia spp. (27; 3.81%), Strongyloides stercoralis (13; 1.8%), Hymenolepis nana (13; 1.8%), and Enterobius vermicularis (2; 0.28%), respectively. Infections were significantly associated with gender (x2 = 14.18; p = 0.002) with males as the most commonly infected with both groups of intestinal parasites (protozoa and helminths). A strong statistical association was noted correlating the parasite occurrence with certain nationalities (x2= 49.5, p <0.001). Furthermore, the study has also found a strong statistical correlation between parasite occurrence and occupation (x2= 15.60; p = 0.029). Multiple infections were not common (3.5% of the positive samples), although one individual (0.14%) had four helminth species, concurrently. These findings emphasized that food handlers with different pathogenic parasitic organisms may pose a significant health risk to the public.