Abstract 3182: Role of Frizzled 7 in melanoma development and metastasis

Abstract The frizzled (Fzd) family of proteins are 7-transmembrane G-protein coupled receptors (GPCRs) that transduce signals mainly for Wnt ligands. There are 10 Fzds identified in mammals, and they are involved in multiple cellular and biological functions via signaling through the canonical Wnt/beta-catenin, planar cell polarity, and calcium signaling pathways. Our previous work revealed a pro-metastasis role of Fzd6 in melanoma. This project focuses on Fzd7, a homolog of Fzd6, in melanoma. We found that FZD7 is highly expressed in multiple melanoma cell lines. siRNA knockdown of FZD7 does not affect cell proliferation but significantly reduces cell invasion in A375, Hs294T, and SK-MEL28 cells in vitro. To determine the in vivo role of Fzd7 in melanoma, we generated Fzd7 knockout YUMM1.7 cell lines for xenograft experiments using CRISPR. All three Fzd7 knockout clones showed a significant reduction in primary tumor growth when xenografted in C57BL/6 mice. To determine the potential mechanism of Fzd7 in melanoma growth and invasion, we performed bulk RNA-Seq on the YUMM1.7 knockout cell lines and identified 215 downregulated and 31 upregulated genes (with a fold change of 2, p<0.05). We are in the process of confirming these transcriptional profile changes. Further functional analysis will be performed using gain- and loss-of-function approaches to determine the downstream mechanisms of Fzd7 in melanoma growth and invasion. Citation Format: Minakshi Nihal, Sheikh A. Umar, An-Bo A. Chang, Nihal Ahmad, Hao Chang. Role of Frizzled 7 in melanoma development and metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3182.