探討SPI-1和SPx在中胚層分化中之角色

Abstract

在過去的許多文獻中都指出，SPI-1和SPx在癌細胞的epithelial-to-mesenchymal transition (EMT) 中扮演相當重要的角色。然而EMT並不是癌細胞特有的能力，在發育過程中，EMT和MET的功能更為複雜，對於許多組織的發育擁有舉足輕重的地位，但SPI-1和SPx在發育中的影響卻仍不清楚。因此本研究證明SPI-1和SPx在ESC和iPSC中皆有高度的表達，並且在經過發育中最早的EMT (中胚層分化) 之後，SPI-1和SPx皆有顯著的下降。更進一步而言，透過knockdown的研究後發現，SPI-1和SPx下降所造成的影響效果非常不穩定，因此在更詳細的了解分化的過程後，發現SPx可能在分化中有關鍵性的作用，該作用可能包含切割EpCAM來影響分化，而SPI-1具有調節SPx的功能，因此在分化中理當不可或缺，然而更詳細的作用機制仍需待未來進一步探討。

SPI-1 (serine protease inhibitor 1) and SPx (serine protease x) are reported to play important roles in epithelial-to-mesenchymal transition (EMT) of cancer cells in many studies. However, the function of SPI-1 and SPx does not well study in development currently even if the EMT and MET are also critical in fetus formation. In this study, we performed immunostaining and confocal microscopy of SPI-1 and SPx in embryonic stem cell (ESC) and induced pluripotent stem cell (iPSC) during mesoderm differentiation which the first EMT function in development. We found that a lot of SPI-1 and few SPx distribute on the membrane of stem cells but SPI-1 and SPx decrease after mesoderm differentiation. However, in our current research results, we find SPx may interact with EpCAM on the cell membrane and affect mesoderm differentiation. The more precise function of the serine protease in mesoderm differentiation should be confirmed in the future study.