Visiting Assistant Project Scientist University of California, Los Angeles University of California, Los Angeles Los Angeles, CA, United States
Background: Hereditary Leiomyomatosis and Renal Cell Carcinoma (HLRCC) is characterized by cutaneous leiomyomas, uterine leiomyomas, and renal cell carcinoma, caused by a germline mutation in the Fumarate Hydratase (FH) gene. HLRCC patients have aggressive disease with poor outcomes due to limited treatment options. Neurofibromatosis 2 (NF2) is an autosomal dominant disease mainly characterized by high risk of schwannomas. NF2 mutations are identified in 15-20% of HLRCC kidney cancer. As there has been extensive research on Neurofibromatosis-related cancers, we created models of the NF-2 deficient HLRCC kidney cancer to assess the biologic effects and therapeutic sensitives to agents that have been investigated in this disease.
Methods: Three isogenic NF2-KO cell lines were generated from NF-2 wild-type HLRCC patients derived cell lines (NCCFH1, UOK262, and UOK268), using CRISPR. Protein abundance was analyzed using Western Blot. Gene expression changes were evaluated using the Nanostring nCounter Tumor Signaling 360 gene expression panel and analyzed by ROSALINDTM. Cell proliferation, soft agar, scratch wound-healing, and transwell invasion assays were performed. Clonogenic survival assays was performed in NF2-KO HLRCC cell lines treated with Rapamycin, GSK2256098, and TAK228.
Results: Loss of function of NF2 increased kidney cancer cell proliferation, migration, invasion, and colony formation. Gene expression profiling revealed increased activation of mammalian target of rapamycin (mTOR) signaling, Glucose Metabolism, HIF1 Signaling. NF2 deficient NCCFH1 and UOK262 models displayed increased sensitivity to rapamycin.
Conclusions: Our current data indicated that FH deficient cell lines with NF2 loss of function may have more aggressive potential, and further suggest that mTOR complex-1 (mTORC-1) therapy could play a role into treatment algorithms of NF-2 deficient HLRCC kidney cancers. In vivo experiments are planned to further characterize the models and test therapeutic approaches.
