Gene interactions and pathways from curated databases and text-mining
Cancer Chemother Pharmacol 2012, PMID: 21644050

Evaluating rational non-cross-resistant combination therapy in advanced clear cell renal cell carcinoma: combined mTOR and AKT inhibitor therapy.

Holland, William S; Tepper, Clifford G; Pietri, Jose E; Chinn, Danielle C; Gandara, David R; Mack, Philip C; Lara, Primo N

OBJECTIVE

Inhibition of the mammalian target of rapamycin (mTOR), a regulator of hypoxia inducible factor (HIF), is an established therapy for advanced renal cell cancer (RCC). Inhibition of mTOR results in compensatory AKT activation, a likely resistance mechanism. We evaluated whether addition of the Akt inhibitor perifosine to the mTOR inhibitor rapamycin would synergistically inhibit RCC.

METHODS

Select RCC cell lines were studied [786-O, A498 (VHL mutant), CAKI-1 (VHL wild type), and 769-P (VHL methylated)] with single agent and combination therapy. Growth inhibition was assessed by MTT and cell cycling by flow cytometry. Phospho-AKT (S473) and HIF-2α were assessed by Western blot. Total RNA was isolated from 786-O cells subjected to single agent and combination treatments. In these cells, genome-wide expression profiles were assessed, and real-time PCR was used to confirm a limited set of expression results.

RESULTS

Three out of four cell lines (CAKI-1, 769-P, and 786-O) were sensitive to single-agent perifosine with 50% inhibitory concentrations ranging from 5 to 10 μM. Perifosine blocked phosphorylation of AKT induced by rapamycin and inhibited HIF-2α expression in 786-O and CAKI-1. Combined treatment resulted in sub-additive growth inhibition. GeneChip analysis and pathway modeling revealed inhibition of the IL-8 pathway by these agents, concomitant with up-regulation of the KLF2 gene, a known suppressor of HIF1α.

CONCLUSIONS

Perifosine is active in select RCC lines, abrogating the induction of AKT phosphorylation mediated by mTOR inhibition. Combined mTOR and AKT inhibition resulted in the modulation of pro-angiogenesis pathways, providing a basis for future investigations.

Diseases/Pathways annotated by Medline MESH: Carcinoma, Renal Cell, Kidney Neoplasms, Neovascularization, Pathologic
Document information provided by NCBI PubMed

Text Mining Data

AKT ⊣ mTOR: " Perifosine is active in select RCC lines, abrogating the induction of AKT phosphorylation mediated by mTOR inhibition "

Manually curated Databases

No curated data.