TY - JOUR
T1 - Therapeutic targeting of TFE3/IRS-1/PI3K/mTOR axis in translocation renal cell carcinoma
AU - Damayanti, Nur P.
AU - Budka, Justin A.
AU - Khella, Heba W.Z.
AU - Ferris, Mary W.
AU - Ku, Sheng Yu
AU - Kauffman, Eric
AU - Wood, Anthony C.
AU - Ahmed, Khunsha
AU - Chintala, Venkata Nithinsai
AU - Adelaiye-Ogala, Remi
AU - Elbanna, May
AU - Orillion, Ashley
AU - Chintala, Sreenivasulu
AU - Kao, Chinghai
AU - Marston Linehan, W.
AU - Yousef, George M.
AU - Hollenhorst, Peter C.
AU - Pili, Roberto
N1 - Publisher Copyright:
©2018 American Association for Cancer Research.
PY - 2018/12/1
Y1 - 2018/12/1
N2 - Purpose: Translocation renal cell carcinoma (tRCC) represents a rare subtype of kidney cancer associated with various TFE3, TFEB, or MITF gene fusions that are not responsive to standard treatments for RCC. Therefore, the identification of new therapeutic targets represents an unmet need for this disease. Experimental Design: We have established and characterized a tRCC patient-derived xenograft, RP-R07, as a novel preclinical model for drug development by using next-generation sequencing and bioinformatics analysis. We then assessed the therapeutic potential of inhibiting the identified pathway using in vitro and in vivo models. Results: The presence of a SFPQ-TFE3 fusion [t(X;1) (p11.2; p34)] with chromosomal break-points was identified by RNA-seq and validated by RT-PCR. TFE3 chromatin immunoprecipitation followed by deep sequencing analysis indicated a strong enrichment for the PI3K/AKT/mTOR pathway. Consistently, miRNA microarray analysis also identified PI3K/AKT/mTOR as a highly enriched pathway in RP-R07. Upregulation of PI3/AKT/mTOR pathway in additional TFE3–tRCC models was confirmed by significantly higher expression of phospho-S6 (P < 0.0001) and phospho-4EBP1 (P < 0.0001) in established tRCC cell lines compared with clear cell RCC cells. Simultaneous vertical targeting of both PI3K/AKT and mTOR axis provided a greater antiproliferative effect both in vitro (P < 0.0001) and in vivo (P < 0.01) compared with single-node inhibition. Knockdown of TFE3 in RP-R07 resulted in decreased expression of IRS-1 and inhibited cell proliferation. Conclusions: These results identify TFE3/IRS-1/PI3K/AKT/ mTOR as a potential dysregulated pathway in TFE3–tRCC, and suggest a therapeutic potential of vertical inhibition of this axis by using a dual PI3K/mTOR inhibitor for patients with TFE3–tRCC.
AB - Purpose: Translocation renal cell carcinoma (tRCC) represents a rare subtype of kidney cancer associated with various TFE3, TFEB, or MITF gene fusions that are not responsive to standard treatments for RCC. Therefore, the identification of new therapeutic targets represents an unmet need for this disease. Experimental Design: We have established and characterized a tRCC patient-derived xenograft, RP-R07, as a novel preclinical model for drug development by using next-generation sequencing and bioinformatics analysis. We then assessed the therapeutic potential of inhibiting the identified pathway using in vitro and in vivo models. Results: The presence of a SFPQ-TFE3 fusion [t(X;1) (p11.2; p34)] with chromosomal break-points was identified by RNA-seq and validated by RT-PCR. TFE3 chromatin immunoprecipitation followed by deep sequencing analysis indicated a strong enrichment for the PI3K/AKT/mTOR pathway. Consistently, miRNA microarray analysis also identified PI3K/AKT/mTOR as a highly enriched pathway in RP-R07. Upregulation of PI3/AKT/mTOR pathway in additional TFE3–tRCC models was confirmed by significantly higher expression of phospho-S6 (P < 0.0001) and phospho-4EBP1 (P < 0.0001) in established tRCC cell lines compared with clear cell RCC cells. Simultaneous vertical targeting of both PI3K/AKT and mTOR axis provided a greater antiproliferative effect both in vitro (P < 0.0001) and in vivo (P < 0.01) compared with single-node inhibition. Knockdown of TFE3 in RP-R07 resulted in decreased expression of IRS-1 and inhibited cell proliferation. Conclusions: These results identify TFE3/IRS-1/PI3K/AKT/ mTOR as a potential dysregulated pathway in TFE3–tRCC, and suggest a therapeutic potential of vertical inhibition of this axis by using a dual PI3K/mTOR inhibitor for patients with TFE3–tRCC.
UR - https://www.scopus.com/pages/publications/85053175074
U2 - 10.1158/1078-0432.CCR-18-0269
DO - 10.1158/1078-0432.CCR-18-0269
M3 - Article
C2 - 30061365
AN - SCOPUS:85053175074
SN - 1078-0432
VL - 24
SP - 5977
EP - 5989
JO - Clinical Cancer Research
JF - Clinical Cancer Research
IS - 23
ER -