Bleomycin (BLM) is an effective anti-carcinogen. With the main detrimental effects of inducing pulmonary fibrosis on patients, its clinical use is limited. Developing agents that enhance the efficacy and attenuate the side effects of cancer chemotherapy are critical. Andrographolide (Andro), an active diterpenoid labdane component extracted from Andrographis panicula, is generally prescribed for treatment of inflammatory associated diseases. The study showed that BLM combined with Andro was significantly more effective than BLM alone on inhibiting the tumor growth, arresting the cell cycle at G0/G1 phase, promoting the capase - 3 and capase - 8 activity to induce cancer cell apoptosis. The underlying mechanisms may be related to the transcriptional regulation of P53/P21/Cyclin pathways. Moreover, BLM induced pulmonary fibrosis in tumor-bearing mice, but BLM combined with Andro dramatically alleviated the lesion in pulmonary fibrosis by activating the SOD, suppressing MDA and HYP production, in the meanwhile attenuating the IL-1 beta, TNF-alpha, IL-6 and TGF-beta 1 level. These mechanisms were associated with its effect on inhibition of protein expression of TGF-beta, alpha-SMA, p-Smad2/3, enhanced expression of Smad7. Thus, it demonstrated that Andro might be a potential adjuvant therapeutic agent for BLM. (C) 2016 Elsevier B.V. All rights reserved.