학술논문

Downregulation of PIK3CA via antibody-esiRNA-complexes suppresses human xenograft tumor growth.
Document Type
Article
Source
PLoS ONE. 7/12/2018, Vol. 13 Issue 7, p1-22. 22p.
Subject
*SMALL interfering RNA
*TUMOR growth
*ENDORIBONUCLEASES
*PHOSPHATIDYLINOSITOL 3-kinases
*CETUXIMAB
*THERAPEUTICS
Language
ISSN
1932-6203
Abstract
Precision cancer therapy requires on the one hand detailed knowledge about a tumor’s driver oncogenes and on the other hand an effective targeted therapy that specifically inhibits these oncogenes. While the determination of genomic landscape of a tumor has reached a very precise level, the respective therapy options are scarce. The application of small inhibitory (si) RNAs is a promising field of investigation. Here, we present the effective in vivo-treatment of colorectal cancer (CRC) xenograft tumors with antibody-complexed, endoribonuclease-prepared small inhibitory (esi)RNAs. We chose heterogeneous endoribonuclease-prepared siRNA pools (esiRNAs) against the frequently mutated genes PIK3CA and KRAS and coupled them to the anti-EGFR antibody cetuximab, which was internalized specifically into the tumor cells. esiRNA pools have been shown to exhibit superior specificity in target gene knockdown compared to classic siRNAs. We identified a significant decrease in tumor growth upon this treatment due to decreased tumor cell proliferation. The ex vivo-analysis of the xenograft CRC tumors revealed the expected downregulation of the intended direct targets PIK3CA and KRAS on protein level. Moreover, known downstream targets for EGFR signaling such as p-ERK, p-AKT, and c-MYC were decreased as well. We therefore propose the use of antibody-esiRNA complexes as a novel experimental treatment option against key components of the EGFR signaling cascade. [ABSTRACT FROM AUTHOR]