Abstract 1710: DPF3 over-expression oncogenic effect in renal cancer is through SWI/SNF BAF complex
Authors: Leticia Andrade Costa, Aline Gomes Souza, Vírginia Campos Silvestrini, Timothy Myers, Vitor Marcel Faça, Stephen Chanock, Leandro Machado Colli
Journal: Cancer Research (2024)

Abstract Renal Cancer (RCC) is the seventh most common type of cancer in the United States, and most part of these tumors do not respond to radiation and chemotherapy treatments. A Genome Wide Association Study (GWAS) identified 13 regions that are related to the risk of developing RCC, and one of this regions is the 14q24 region, a region that has already been shown to have a Single Nucleotide Polymorphism (SNP) involved in the development of RCC, by which the presence of the risk allele is capable of increase the expression of DPF3 and this increase is capable of regulated the RCC cell line proliferation. It is very published the oncogenic effect of DPF3 in RCC, however, the mechanism by which DPF3 is acting is not very knew. Our objective is to understand the mechanisms by which DPF3 regulate renal cancer development. For this, we did a co-immunoprecipitation of DPF3 with nuclear extract of RCC cell line that overexpress DPF3 and analyze the interactions between DPF3 and other proteins of SWI/SNF Complex. We did a proteomic analyzes in Targeted Mass Spectrometry (MRM) for see the proteins levels. We could see an increase in expression of other SWI/SNF BAF Complex proteins in RCC cell line that overexpress DPF3, such like SMARCA2, SMARCE1 and ARID1A, suggesting a relation between DPF3 and SWI/SNF BAF Complex and evidencing that DPF3 is acting through BAF Complex. To extend the evaluation of DPF3 we inhibit the expression of the SNP associated with the 14q24 region, rs4903064, in renal cancer cell lines (UOK121, SN12C and 786-O) using the CRISPRi technic and analyze the role of this SNP in DPF3, CEMIP and IL23R expression. Our initial results demonstrate that in the UOK121 and SN12C lineage, the inhibition of the SNP was able to decrease the expression of DPF3, and in the SN12C cell line we also see a decrease in CEMIP expression. When we analyze the 786-O cell line, we see that the blockade of SNP does not change the expression of DPF3, nor of the other genes, indicating that the action of the SNP on DPF3 occurs only in the presence of the risk allele for RCC. We also use a murine (Renca) RCC cell line that overexpress DPF3 under regulation of TetOn promoter and we did an in vivo experiment in mouse (Balb/c and Balb/c Nude), for analyze the function of DPF3 in tumor growth, migration and proliferation. When we inject (s.c) in Balb/c Nude we could see an increase in tumor growth, in tumor volume and weight in the group treated with doxycycline diet when compare with de control group, suggesting that DPF3 is capable of increase RCC growth. We also analyze the DPF3 function in RCC invasion and migration, and when we inject (intrarenal) in Balb/c we could see a metastatic signal in the lung. The lung of the animals treated with doxycycline diet presents an increase in volume and weight when compare with the control group. In this way, the study of genetic and proteomic behind DPF3 function and RCC development is essential for a biomarker discovery and help in the patient prognosithes and treatment. Citation Format: Leticia Andrade Costa, Aline Gomes Souza, Vírginia Campos Silvestrini, Timothy Myers, Vitor Marcel Faça, Stephen Chanock, Leandro Machado Colli. DPF3 over-expression oncogenic effect in renal cancer is through SWI/SNF BAF complex [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 1710.