Weiting Liang, Kawaguchi Makiko, Fukushima Tsuyoshi, Sato Yuichiro
Section of Oncopathology and Morphological Pathology, Department of Pathology, Faculty of Medicine, University of Miyazaki, 5200 Kihara, Kiyotake, Miazaki, 889-1692, Japan.
Hum Cell. 2024 Dec 28;38(1):36. doi: 10.1007/s13577-024-01159-7.
Hepatocyte growth factor activator inhibitor type 1 (HAI-1), which is encoded by the SPINT1 gene, is a membrane-associated serine proteinase inhibitor abundantly expressed in epithelial tissues. We had previously demonstrated that HAI-1 is critical for placental development, epidermal keratinization, and maintenance of keratinocyte morphology by regulating cognate proteases, matriptase and prostasin. After performing ultrastructural analysis of Spint1-deleted skin tissues, our results showed that Spint1-deleted epidermis exhibited partially disrupted epidermal basement-membrane structures. Matrix metalloproteinases-9 (MMP-9) expression levels were upregulated in Spint1-deleted primary cultured keratinocytes and SPINT1 knockout (KO) HaCaT cells. Furthermore, gelatin zymography of the conditioned medium showed increased MMP activities in keratinocytes with reduced HAI-1 expression. Treating SPINT1 KO HaCaT cells with dehydroxymethylepoxyquinomicin (DHMEQ), a small molecule inhibitor of NF-κB, abrogated the upregulation of MMP9 and the gelatinolytic activity associated with MMP-9. These results suggest that HAI-1 may play a critical role in epidermal basement membrane integrity by regulating NF-κB activation-induced upregulation of MMP-9.
1型肝细胞生长因子激活剂抑制剂（HAI-1）由SPINT1基因编码，是一种与膜相关的丝氨酸蛋白酶抑制剂，在上皮组织中大量表达。我们之前已经证明，HAI-1通过调节同源蛋白酶——matriptase和前列腺素，对胎盘发育、表皮角质化和角质形成细胞形态的维持至关重要。在对Spint1基因缺失的皮肤组织进行超微结构分析后，我们的结果显示，Spint1基因缺失的表皮呈现出部分破坏的表皮基底膜结构。基质金属蛋白酶-9（MMP-9）在Spint1基因缺失的原代培养角质形成细胞和SPINT1基因敲除（KO）的HaCaT细胞中的表达水平上调。此外，条件培养基的明胶酶谱分析显示，HAI-1表达降低的角质形成细胞中MMP活性增加。用NF-κB的小分子抑制剂去氢甲基环氧喹霉素（DHMEQ）处理SPINT1基因敲除的HaCaT细胞，可消除MMP9的上调以及与MMP-9相关的明胶酶解活性。这些结果表明，HAI-1可能通过调节NF-κB激活诱导的MMP-9上调，在表皮基底膜完整性中发挥关键作用。
