Figure 4.

HighMCT4 Expression Supports Cell Growth of the Aerobic Glycolysis-Preference NSCLC Cell Subtype

(A) The protein level of MCT4 after transduction with shRNA virus targeting SLC16A3 gene or LacZ control was detected by immunoblotting in CL1-5 and Hop62 cells. (B) The cell proliferation rate of CL1-5 and Hop62 cells after transduction with shRNA virus targeting SLC16A3 gene or LacZ control was detected by SRB assays. The cells were fixed at the indicated day and detected as described in the Materials and Methods. The graph indicated the fold change between each day versus day 0. Data represent mean and SD. n = 3. (C) The colony formation ability of CL1-5 and Hop62 cells was detected by colony-formation assays after transduction with shRNA virus targeting SLC16A3 gene or LacZ control. The colonies were fixed, stained, and dissolved as described in the Materials and Methods. The graph indicated the total absorbance values at 490 nm in shMCT4 groups relative to that in shLacZ groups, which were set to 100%. Data represent mean and SD. n = 3. (D) Representative in vivo imaging system (IVIS) images of male nude mice captured 14 days after orthotopic implantation of CL1-5-Luc cells with or without MCT4 knockdown by shRNA virus. The luminescence intensity of photons emitted from each tumor was quantified as shown in the figure. Data represent mean and SD. n = 3. (E) Hop62 cells were transduced with inducible-shRNA virus targeting SLC16A3 gene or LacZ control and treated with doxycycline hyclate at 3 μg/mL concentration for 5 days. The MCT4 expression in these cells was shown in the western blotting plot. Following the validation, these cells were implanted subcutaneously in nude mice. Mice were treated with doxycycline hyclate (25 mg/kg) daily by oral gavage and the growth curve of Hop62 subcutaneous tumors was measured for 10 days. Data represent mean and SD. n = 6.