RESUMO
Activation of signal transducer and activator of transcription (STAT)3 has been reported in many cancers. It is also well known that STAT3 is activated in skin lesions of psoriasis, a chronic skin disease. In this study, to ascertain whether patients with psoriasis have a predisposition to STAT3 activation, we examined phosphorylated STAT3 in cancer cells of psoriasis patients via immunohistochemistry. We selected patients with psoriasis who visited the Department of Dermatology, Jichi Medical University Hospital, from January 2000 to May 2015, and had a history of cancer. We performed immunostaining for phosphorylated STAT3 in tumor cells of five, four, and six cases of gastric, lung, and head and neck cancer, respectively. The results showed that there was no significant difference in STAT3 activation in any of the three cancer types between the psoriasis and control groups. Although this study presents limitations in its sample size and inconsistency in the histology and differentiation of the cancers, results suggest that psoriasis patients do not have a predisposition to STAT3 activation. Instead, STAT3 activation is intricately regulated by each disorder or cellular microenvironment in both cancer and psoriasis.
RESUMO
BACKGROUND: SOX9 is a marker for stem cells in the intestine and overexpression of SOX9 is found in some types of cancer. However, the expression of SOX9 in normal stomach, precancerous intestinal metaplasia, and gastric carcinoma has not yet been clarified. This study aimed to investigate SOX9 expression in the corpus and pyloric regions of the normal human stomach, premalignant intestinal metaplasia, and gastric carcinoma by using immunohistochemistry. METHODS: We evaluated SOX9 expression in 46 clinical samples (early gastric well-differentiated adenocarcinoma including surrounding intestinal metaplasia) resected under esophagogastroduodenoscopy. RESULTS: A small amount of SOX9 was expressed in the neck/isthmus of the corpus region and SOX9 expression was predominantly restricted to the neck/isthmus of the pyloric region in normal human stomach. In the intestinal metaplastic mucosa, SOX9- and PCNA-positive cells were located at the base of the intestinal metaplastic mucosa. Almost all of the gastric carcinoma cells expressed SOX9. CONCLUSION: SOX9 is expressed in intestinal metaplasia and gastric carcinoma in humans.
