Exploring the Inhibitor of Apoptosis BIRC6 as a Target for Lung Cancer Therapy.

GÓMEZ BERGNA SANTIAGO MANUEL; ROMANOWSKI VÍCTOR; GOTTARDO MARÍA FLORENCIA; PIDRE MATIAS LUIS; MARCHESINI ABRIL; CANDOLFI MARIANELA

Buenos Aires

Congreso; LXV REUNIÓN ANUAL DE LA SOCIEDAD ARGENTINA DE INVESTIGACIÓN CLÍNICA (SAIC); 2020

SAIC

Inhibitors of apoptosis (IAP) have been shown to play a central role in the development and aggressiveness of different tumors. In particular, overexpression of BIRC6, a member of the IAP family, is associated with a poor prognosis in different tumors. The aim of this work was to select a possible therapeutic target through a transcriptomic analysis of the IAP family in lung cancer and develop baculovirus-based gene therapy vectors. We focused the transcriptomic analysis on Lung Adenocarcinoma (LAC) and Lung Squamous Cell Carcinoma (LSCC). Two TCGA databases were analyzed for each cancer type and seven IAP were queried (cBioPortal and Xena platform). Our results demonstrated that at least two (BIRC5 and BIRC6) of the seven IAP have a higher expression in tumor compared to normal tissue in both types of tumors (ANOVA). Also, our results showed that LAC patients with alterations in the birc6 gene copy number have a shorter median months of each disease status compared to the unaltereted group. Moreover, we observed that a higher copy number of birc6 was associated with resistance to radiotherapy and tumor recurrence (ANOVA).In order to characterize the role of BIRC6 in LAC, we designed three shRNAs targeting different regions of the birc6 gene. Using bioinformatic methods we evaluated different parameters of the shRNAS (structure, stability, etc). Next, three recombinant baculoviruses (BV) were generated carrying each of these shRNA sequences and the reporter gene dTomato. The effect of BV-mediated birc6 silencing was evaluated in the human LAC cell line A549 by immunofluorescence and flow cytometry. Apoptosis levels were measured by TUNEL. One of the recombinant BV effectively reduced BIRC6 expression and induced apoptosis in 30% of the A549 treated cells (t test).These results are encouraging and open the way to future preclinical studies, postulating BIRC6 as a promising therapeutic target, and the recombinant BV as a possible gene therapy vector against LAC.