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Based on the analysis of patients with Peutz-Jeghers syndrome (PJS), Serine threonine kinase11 (STK11) is known as a tumor suppressor gene, which is involved in cell polarization, regulation of apoptosis, and DNA damage response. In this case report study, we examined STK11 gene sequencing in a 42-year-old woman with mucocuta neous pigmentation and positive family history. Endoscopy and colonoscopy showed >1000 polyps throughout the stomach/colon (PJ-type hamartomas). The larger polyp in the stomach was resected and the small bowel imaging detected multiple jejunum/ileum small polyps. The data released from the sequencing results revealed five alterations in exons 1 to 5. The major mutation in stop codon was reported as converted to the amino acid tryptophan (TRP) to tyrosine (TER). The TGG codon was converted to TAG by mutation. Finally, another novel mutation in STK11 stop codon as a 'de novo' variant was seen. It is predicted that stop codon mutations make the affected person susceptible to developing colorectal cancer., Competing Interests: Authors have no potential conflicts of interest to disclose., (© 2023, Gastroenterology and Hepatology From Bed to Bench (GHFBB).)

Aim: Given the high similarity of phenotypical and secretory properties of mesenchymal stem cells and fibroblasts, this study investigated the possibility of inducing EMT process by mesenchymal stem cells., Background: Annually, more than 13% of deaths worldwide occur due to cancer. One of the main reasons for the high mortality rate is due to the metastasis of cancer stem cells. Induction of metastasis occurs during the EMT process, which can also be stimulated by fibroblast cells., Methods: Mesenchymal stem cells (MSCs) were isolated and sub-cultured until passage 3 or 4. AGS cells were co-cultured with MSCs for 4 days. As the positive control group, AGS cells were treated with TGF-β (10ng/ml) for 48h. Finally, the mRNA expression level of Vimentin, β-catenin, Snail, and E-cadherin as the EMT pattern, were evaluated by RT-PCR technique., Results: Our findings indicated that AGS cells' crosstalk with MSCs significantly upregulated fibroblast markers including Vimentin and Snail expression. However, no significant changes were identified for β-catenin gene expression. Additionally, AGS treatment with MSCs resulted in diminished E-cadherin in the targeted cells., Conclusion: Based on the results, the AGS cells crosstalk with MSCs activates induction of epithelial mesenchymal transition, which is confirmed through the elevation of Vimentin and Snail expression and reduction of E-cadherin expression as a specific epithelial marker. However, it seems that MSc was not effective on Wnt/ β-catenin signal gastric cancer cell line., Competing Interests: The authors declare that they have no conflict of interest., (©2019 RIGLD.)

Aim: In this study we investigated the prevalence of binary toxin genes, cdtA and cdtB , in clinical isolates of C. difficile from hospitalized patients with diarrhea., Background: C. difficile binary toxin (CDT) is an action-specific ADP-ribosyltransferase that is produced by some strains of C. difficile . Co-expression of this toxin with tcdA and tcdB can lead to more severe disease in CDI patients., Methods: Totally, 930 patients suspected of having CDI was included in this study. All samples were treated with methanol and cultured on selective C. difficile agar plates. The C. difficile isolates were further identified by PCR. Presence of tcdA , tcdB , cdtA , and cdtB genes among the strains were examined by PCR., Results: Analysis of the PCR results showed a prevalence of 85.2% (144/169) for toxigenic C. diffidile . Toxin genotyping of the strains for tcdA and tcdB genes revealed the toxin profiles of A+B+, A+B-, A-B+ accounting for 86.1% (124/144), 7.6% (11/144), 6.2% (9/144) among the strains, respectively. Totally, 12.4% (21/169) of the C. difficile strains were binary toxin-positive. cdtA -B+, cdtA +‏B‏+ and cdtA +B- were detected in 43% (9/21), 38% (8/21) and 19% (4/21) of the strains, respectively. Interestingly, 12% (3/25) of nontoxigenic C. difficile strains ( tcdA -B-) had either cdtA +‏B‏+ or cdtA -B+ profiles., Conclusion: This is the first report for the prevalence of binary toxin genes in C. difficile strains isolated from Iran. Further studies are required to investigate the exact role of binary toxins in the pathogenesis of C. difficile particularly in patients with chronic diarrhea among Iranian populations.