Division of Cancer Biology, National Cancer Center, Goyang 10408, Korea.
Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON K1N 6N5, Canada.
Int J Mol Sci. 2020 Apr 3;21(7):2493. doi: 10.3390/ijms21072493.
In a recent report, no significance of transglutaminase 2 (TGase 2) was noted in the analyses of expression differences between normal and clear cell renal cell carcinoma (ccRCC), although we found that knock down of TGase 2 induced significant p53-mediated cell death in ccRCC. Generally, to find effective therapeutic targets, we need to identify targets that belong specifically to a cancer phenotype that can be differentiated from a normal phenotype. Here, we offer precise reasons why TGase 2 may be the first therapeutic target for ccRCC, according to several lines of evidence. TGase 2 is negatively regulated by von Hippel-Lindau tumor suppressor protein (pVHL) and positively regulated by hypoxia-inducible factor 1-α (HIF-1α in renal cell carcinoma (RCC). Therefore, most of ccRCC presents high level expression of TGase 2 because over 90% of ccRCC showed inactivity through mutation and methylation. Cell death, angiogenesis and drug resistance were specifically regulated by TGase 2 through p53 depletion in ccRCC because over 90% of ccRCC express wild type p53, which is a cell death inducer as well as a HIF-1α suppressor. Although there have been no detailed studies of the physiological role of TGase 2 in multi-omics analyses of ccRCC, a life-long study of the physiological roles of TGase 2 led to the discovery of the first target as well as the first therapeutic treatment for ccRCC in the clinical field.
在最近的一份报告中,尽管我们发现敲低转谷氨酰胺酶 2 (TGase 2)可诱导透明细胞肾细胞癌 (ccRCC) 中 p53 介导的细胞死亡显著增加,但在分析正常和透明细胞肾细胞癌 (ccRCC) 之间表达差异时,并未发现 TGase 2 的显著意义。通常,为了找到有效的治疗靶点,我们需要识别专门属于癌症表型的靶点,这些靶点可以与正常表型区分开来。根据几条证据,我们提供了 TGase 2 可能是 ccRCC 第一个治疗靶点的精确原因。TGase 2 受 von Hippel-Lindau 肿瘤抑制蛋白 (pVHL) 负调控,受缺氧诱导因子 1-α (HIF-1α) 在肾细胞癌 (RCC) 中受正调控。因此,大多数 ccRCC 呈现 TGase 2 的高水平表达,因为超过 90%的 ccRCC 通过突变和甲基化而失活。在 ccRCC 中,通过 p53 耗竭特异性调节细胞死亡、血管生成和耐药性,因为超过 90%的 ccRCC 表达野生型 p53,野生型 p53 既是细胞死亡诱导剂,也是 HIF-1α 抑制剂。尽管在 ccRCC 的多组学分析中尚未对 TGase 2 的生理作用进行详细研究,但对 TGase 2 的生理作用进行终身研究导致发现了第一个针对 ccRCC 的靶点以及临床领域的第一个治疗方法。