Expressions and Significances of CTSL, The Target of COVID‐19 on GBM

Abstract

CTSL is one of the SARS-entry-associated CoV-2's proteases and plays a key role in the virus's entry into the cell and subsequent infection. We investigated the association between the expression level of CTSL and overall survival in TCGA and CGGA databases, in order to better understand the possible route and risks of new coronavirus infection for patients with GBM. Meanwhile, the relationship between CTSL and immune infiltration levels was analyzed by means of the TIMER database. The impact of CTSL inhibitors on GBM biological activity was tested. The findings revealed that GBM tissues had higher CTSL expression levels than that of normal brain tissues, which was associated with a significantly lower survival rate in GBM patients. Meanwhile, CTSL was very negatively correlated with purity, B cell and CD8+ T cell in GBM. CTSL inhibitor significantly reduced U251 cell growth and invasion in vitro and induced mitochondrial apoptosis. According to the findings of this study, CTSL acts as an independent prognostic factor and can be considered as promising therapeutic target for GBM.

COVID-19 receptor and malignant cancers: Association of CTSL expression with susceptibility to SARS-CoV-2

“…Upregulation of CTSL correlates with metastatic aggressiveness and poor prognosis in cancer patients 2 . CTSL expression was shown to be elevated in glioblastoma multiforme (GBM) tissue as compared to the normal brain tissue 3 . Importantly, CTSL can proteolytically cleave the S1 subunit on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein, which is necessary for viral entry into the host cells 4 - 6 .…”