Accession Number : AD1050242

Title :   Targeting Increased Polyamine Transport of Resistant Melanomas

Descriptive Note : Technical Report,01 Aug 2016,31 Jul 2017

Corporate Author : Lankenau Institute for Medical Research Wynnewood United States

Personal Author(s) : Gilmour, Susan

Full Text :

Report Date : 01 Aug 2017

Pagination or Media Count : 26

Abstract : BRAF mutations are present in over half of all melanoma tumors. Although BRAF inhibitors (BRAFi) elicit rapid anti-tumor responses in the majority of patients with mutant BRAFV600E melanoma, the tumors inevitably relapse after a short time and are resistant to further treatment with these drugs. Thus, new therapeutic strategies are urgently needed to overcome the acquired resistance to BRAF inhibitors. Our goal is to test whether melanomas, which develop resistance to BRAF inhibitors, can be successfully treated using a novel arylpolyamine (AP) drug that is cytotoxic upon cellular internalization via the polyamine transport system (PTS). We found that human and murine BRAFV600E melanoma cells demonstrate greater PTS activity and increased sensitivity to AP compared to BRAFWT melanoma cells. Treatment with DFMO upregulates PTS activity in BRAFV600E melanoma cells and further increases their sensitivity to AP. Human BRAFV600E melanoma WM983B-BR subline with acquired BRAFi resistance (following chronic in vitro exposure to the BRAFi, PLX4720) demonstrated increased PTS activity compared to the parental BRAFi-sensitive WM983B cells. Preliminary animal tumor studies have revealed that co-treatment with the BRAF inhibitor, PLX4720, and AP plus DFMO delays the recurrence of BRAFV600E melanoma tumors that occurs in animals treated with PLX4720 alone.

Descriptors :   mutations , skin cancer , neoplasms , inhibitors , drug resistance , macrophages , stem cells , toxicity

Subject Categories : Medicine and Medical Research

Distribution Statement : APPROVED FOR PUBLIC RELEASE