Figure 2.

mTOR signaling and protein levels of epithelial and mesenchymal markers in renal lesions of Tsc2^+/− mice.

(A) mTOR signaling and expression of E-cadherin, vimentin, FSP1, and α-SMA. Adjacent kidney sections prepared from 16-month-old Tsc2^+/− mice were used for IHC. Representative IHC-stained sections were presented to show phosphorylation of S6 at S235/236 and Akt at S473, and protein levels of E-cadherin, vimentin, FSP1, and α-SMA in different types of renal tumors from cystic/papillary lesions to solid malignancies. Black arrows point to tumor cells stained by vimentin, FSP1, or α-SMA in cystic/papillary lesions. Black lines are scale bars.

(B) Expression of vimentin. Kidney sections prepared from 16-month-old Tsc2^+/− mice were used for IHC. Representative IHC-stained sections were presented to show different types of renal tumors negative (−) or positive (+) for vimentin. Higher-power views of boxed areas are presented next to the corresponding lower-power images. Black lines are scale bars.

(C) Identification of tumor cells with partial EMT. Kidney sections prepared from 16-month-old Tsc2^+/− mice were used for MS-IHC. The same kidney sections were subjected to three rounds of IHC to sequentially detect three indicated antigens. Representative images were presented to show examples of tumor cells co-expressing E-cadherin and vimentin/FSP1 in circled areas. Higher-power views of boxed areas are presented next to the corresponding lower-power images. Around 60.1% (11.6%-96.8%) of tumor cells co-expressed E-cadherin and vimentin (and or FSP1) as estimated from 10 mouse renal carcinomas. Black lines are scale bars.