Fig. 5.

SMARCB1-deficient tumor cells are more resistant to hypoxia and expand under hypoxic conditions. Preventing the degradation of SMARCB1 significantly impairs tumor expansion. (A) Microscopic images of SMARCB1^Null mouse renal tumors (GFP) and SMARCB1^WT cells (GFP/RFP) prior to subcutaneous injection into NSG mice. (B) Flow cytometry evaluation of SMARCB1^Null and SMARCB1^WT tumor cells that were mixed in a 1:1 ratio and injected subcutaneously into NSG mice. (C) Immunoblotting analysis of SMARCB1 protein expression in RMC219-tet-empty vector (SMARCB1^Null) and RMC219-tet-inducible SMARCB1^WT and RMC219-tet-inducible SMARCB1^K62R after 7 d of treatment with 2 μg of Doxycycline (DOX). (D) Corresponding microscopic images of RMC219-tet-inducible cells showing that cells are healthy prior to subcutaneous injection in NSG mice. (E) Growth curve of subcutaneous tumors in NSG mice. (F) Kaplan–Meier survival curve of RMC219 subcutaneous tumors. For time-to-event event-free survival analysis, 200 mm³ was set as the endpoint. (G) Final tumor mass of RMC219 subcutaneous tumors. Data are expressed as mean value ±SD, with the P value calculated by Student’s t test.