Citation
- Authors: Zhu EY. et al.
- Year: 2022
- Journal: NPJ Precis Oncol 6 74
- Applications: in vitro / DNA / jetOPTIMUS
- Cell types:
- Name: PDX10
- Name: SK-MEL-28
Description: Huma skin melanoma cell line - Name: UACC-257
Method
Enforced expression RAC1P29S was performed using a piggyBac transposon-transposase system. Namely, cells were seeded in a 6-well format. 24h later, empty vector or RAC1P29S plasmid were mixed at 1:5 ratio with the PiggyBac transposase plasmid and delivered into cells with Jetoptimus DNA transfection reagent using the standard workflow. Media was changed 6–24h later. Cells were selected with puromycin for six days with media changes every two days.
Abstract
Rare gain-of-function mutations in RAC1 drive drug resistance to targeted BRAF inhibition in cutaneous melanoma. Here, we show that wildtype RAC1 is a critical driver of growth and drug resistance, but only in a subset of melanomas with elevated markers of de-differentiation. Similarly, SRC inhibition also selectively sensitized de-differentiated melanomas to BRAF inhibition. One possible mechanism may be the suppression of the de-differentiated state, as SRC and RAC1 maintained markers of de-differentiation in human melanoma cells. The functional differences between melanoma subtypes suggest that the clinical management of cutaneous melanoma can be enhanced by the knowledge of differentiation status. To simplify the task of classification, we developed a binary classification strategy based on a small set of ten genes. Using this gene set, we reliably determined the differentiation status previously defined by hundreds of genes. Overall, our study informs strategies that enhance the precision of BRAFi by discovering unique vulnerabilities of the de-differentiated cutaneous melanoma subtype and creating a practical method to resolve differentiation status.