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Hepatocyte growth factor activator inhibitor‐1 (HAI‐1), encoded by the SPINT1 gene, is a membrane‐bound protease inhibitor expressed on the surface of epithelial cells. Hepatocyte growth factor activator inhibitor‐1 regulates type II transmembrane serine proteases that activate protease‐activated receptor‐2 (PAR‐2). We previously reported that deletion of Spint1 in ApcMin/+ mice resulted in accelerated formation of intestinal tumors, possibly through enhanced nuclear factor‐κB signaling. In this study, we examined the role of PAR‐2 in accelerating tumor formation in the ApcMin/+ model in the presence or absence of Spint1. We observed that knockout of the F2rl1 gene, encoding PAR‐2, not only eliminated the enhanced formation of intestinal tumors caused by Spint1 deletion, but also reduced tumor formation in the presence of Spint1. Exacerbation of anemia and weight loss associated with HAI‐1 deficiency was also normalized by compound deficiency of PAR‐2. Mechanistically, signaling triggered by deregulated protease activities increased nuclear translocation of RelA/p65, vascular endothelial growth factor expression, and vascular density in ApcMin/+‐induced intestinal tumors. These results suggest that serine proteases promote intestinal carcinogenesis through activation of PAR‐2, and that HAI‐1 plays a critical tumor suppressor role as an inhibitor of matriptase, kallikreins, and other PAR‐2 activating proteases.  相似文献   
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miRNA‐221 (miR‐221) is known to be abnormally expressed in many human cancers. The serum levels of miR‐221 have been reported as a tumor marker for malignant melanoma (MM). We hypothesized that the hair shaft miR‐221 levels may be increased in patients with MM. We therefore assessed the possibility that hair shaft miR‐221 levels could be a marker for MM. The hair shaft miR‐221 levels were significantly higher in patients with MM than controls. The rates of increased hair shaft miR‐221 levels above the cut‐off value were comparable to those of serum 5‐S‐CD, which is a tumor marker commonly used for MM. Measurements of the hair shaft miR‐221 levels could have potential clinical value in the detection of MM. This is the first report investigating the hair shaft levels of an miRNA in patients with MM. Our investigations offer new insight into the relationship between miR‐221 and MM, and may provide a new, non‐invasive way to screen for melanoma.  相似文献   
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Pyoderma gangrenosum (PG) is an extra-intestinal skin lesion in inflammatory bowel disease (IBD) as is erythema nodosum. Vedolizumab (VED) is a monoclonal antibody that targets α4β7 integrin and has an intestinal selective mechanism. Despite good therapeutic effects on colitis, the effect on extra-intestinal manifestations (EIMs) remains unclear. Here we report a case of ulcerative colitis complicated by PG during treatment with VED, which was successfully treated with prednisolone in combination with adsorptive granulocyte and monocyte apheresis (GMA). The patient was a 50-year-old woman with a past medical history of extensive ulcerative colitis managed by golimumab (GLM). She developed flare symptoms due to loss of response to GLM, and treatment was switched to VED. Her gastrointestinal symptoms were improved with VED treatment with less frequent bowel movements. However, infiltrative erythema with pain appeared on the right lower leg and right knee, and expanded and gradually ulcerated. Her skin lesions were treated with corticosteroid, but showed poor improvement. Therefore, granulocyte and monocyte apheresis (GMA) treatment was administered in combination with prednisolone. After 3 months, the ulcer gradually improved, and at the time of this writing, the eruptions were nearly replaced by epithelial tissue. This case study showed that patients with UC and EIMS may respond well to combination therapy of VED and GMA. GMA has a very favorable safety profile. On the other hand, the causal connection between VED and PG is still unclear. We believe that a combination therapy involving VED and GMA in IBD patients with EIMs warrants consideration.  相似文献   
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PurposePrevious studies have reported different methods of estrogen administration during endometrial preparation for frozen‐thawed embryo transfer (FET). This study aimed to investigate a beneficial regimen of transdermal estrogen administration for FET.MethodsWe investigated the reproductive and obstetric outcomes of FET by comparing the increasing dose (ID) group that mimics changes in serum estradiol during the menstrual cycle and the constant dose (CD) group. Transdermal patches were used for estrogen administration in both groups. In our hospital, we targeted 315 cycles of the ID group in which FET was performed in 2017 and 324 cycles of the CD group in which FET was performed in 2018. In all cases, single embryo transfer was performed.ResultsAll were singleton pregnancies. There was no difference in clinical pregnancy rate (28.9% vs 28.2%, P =.837) and live birth rate (17.3% vs 21.4%, P =.201) between the ID and CD groups. Spontaneous abortion rate was significantly lower in the CD group than in the ID group (37.2% vs 23.0%, P =.041). There was no difference in obstetrical outcomes.ConclusionsIt was considered that the simple CD regimen may be more beneficial than the complicated ID regimen.  相似文献   
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