TGFB1 and cancer: In summary, after confirming that treatment with R1-Ki suppressed TGF-β signaling in vivo, we found that TGF-β signaling is involved in the increase of tumor volume, and was involved in tumor cell proliferation, the suppression of TGF-β signaling, and did not induce necrosis or apoptosis in the proliferating cancer cells in the bone micro-E.