Figure 6

TGFBI induces cellular senescence. (A) Mesothelioma and (B) breast cancer cell lines with and without re-expression of TGFBI were sub-cultured and then maintained for 2 days in growth medium prior to assay for SA-β-Gal staining. Most of the T2807 and T2313 cells were SA-β–Gal-positive (right panels of A, B, ×200), and most of the V2801 and V23113 cells were SA-β–Gal-negative (left panels of A, B, ×200). (C) Mesothelioma and (D) breast tumor cell extracts were prepared, and telomerase activity was assayed using QTD real-time PCR. Data are shown as the threshold cycle (Ct) of real-time PCR relative to vector control cells, *, P < 0.01. Expression of p16 and p14 in (E) mesothelioma and (F) breast tumor cells was assessed by Western blotting with whole-cell lysates from harvested cells.