鈣網蛋白在前列腺癌細胞中調控岩藻醣轉移酶表現及β1型整合蛋白岩藻醣化之研究

Abstract

鈣網蛋白是一種主要分佈在內質網當中的伴護蛋白，已知會影響膀胱癌細胞的生長與移行。在過去研究中，我們發現鈣網蛋白會增加膀胱癌細胞內岩藻醣轉移酶的表現，並且提升β1型整合蛋白的岩藻醣化與細胞的貼附能力。然而，鈣網蛋白在前列腺癌細胞當中對於上述細胞生理機制的影響仍未明確，因此在本研究中，我們將研究鈣網蛋白在前列腺癌細胞中所扮演的角色。實驗結果顯示，在抑制鈣網蛋白表現後，岩藻醣轉移酶表現量與β1型整合蛋白之岩藻醣化程度下降，且岩藻醣轉移酶轉移酶表現量的的影響可能是透過可能是透過調節其mRNA穩定性。此外，抑制鈣網蛋白表現亦會降低細胞的貼附能力與整合蛋白的活化程度。這些結果表示鈣網蛋白對於前列腺癌細胞的移行可能有重要影響，並且可能是透過岩藻醣轉移酶來達成，未來對鈣網蛋白的更深入研究將有助於前列腺癌治療的發展。

Calreticulin (CRT) is a multifunctional ER chaperon protein and it had been revealed that knockdown of CRT may suppress cell proliferation and migration in J82 bladder cancer cell. We had further demonstrated that CRT enhanced the expression of fucosyltransferase1 (FUT1), which leads to an enhancement of fucosylation of beta1 integrin, and promote cell adhesion in J82 cells. Previous studies had shown that knockdown of CRT suppress cell proliferation and migration in PC3 prostate cancer cell as well. However, the effects by CRT on integrin fucosylation have not been revealed in prostate cancer so far. In this study, therefore, we attempted to investigate whether CRT affect FUT1 expression and integrin fucosylation in PC3 prostate cancer cells as well. Our results showed that FUT1 expression and beta1 integrin fucosylation are suppressed after knockdown of CRT. Futhermore, cell adhesion and integrin activation are down regulated as well. These observations imply that CRT might regulate prostate cancer metastasis through FUT1 and therefore could be a potential target for development of cancer treatments.