Targeting mTORC2 inhibits colon cancer cell proliferation in vitro and tumor formation in vivo.
The mammalian target of rapamycin (mTOR), which exists in two functionally distinct complexes, mTORC1 and mTORC2 plays an important role in tumor growth. Whereas the role of mTORC1 has been well characterized in this process, little is known about the functions of mTORC2 in cancer progression. In this study, we explored the specific role of mTORC2 in colon cancer using a short hairpin RNA expression system to silence the mTORC2-associated protein rictor. We found that downregulation of rictor in HT29 and LS174T colon cancer cells significantly reduced cell proliferation. Knockdown of rictor also resulted in a G1 arrest as observed by cell cycle analysis. We further observed that LS174T cells deficient for rictor failed to form tumors in a nude mice xenograft model. Taken together, these results show that the inhibition of mTORC2 reduces colon cancer cell proliferation in vitro and tumor xenograft formation in vivo. They also suggest that specifically targeting mTORC2 may provide a novel treatment strategy for colorectal cancer.
Department of Visceral Surgery, Centre Hospitalier Universitaire Vaudois and University of Lausanne, 1011 Lausanne, Switzerland.
Didier
D
Roulin
Yannick
Y
Cerantola
Anne
A
Dormond-Meuwly
Nicolas
N
Demartines
Olivier
O
Dormond
D048868:Adaptor Proteins, Signal Transducing; D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D003110:Colonic Neoplasms / Q000378:metabolism* / Q000473:pathology*; D015536:Down-Regulation; D055785:Gene Knockdown Techniques; D006801:Humans; D051379:Mice; D011506:Proteins / Q000378:metabolism; D000076226:Rapamycin-Insensitive Companion of mTOR Protein; D000076223:Regulatory-Associated Protein of mTOR; D014157:Transcription Factors / Q000378:metabolism*; D023041:Xenograft Model Antitumor Assays
D048868:Adaptor Proteins, Signal Transducing; C493245:CRTC2 protein, human; D002352:Carrier Proteins; D011506:Proteins; C492571:RICTOR protein, human; C463659:RPTOR protein, human; D000076226:Rapamycin-Insensitive Companion of mTOR Protein; D000076223:Regulatory-Associated Protein of mTOR; D014157:Transcription Factors