ABSTRACT
The cure of tumors is a difficulty in the world, and both the quality of life and the survival rate of patients remain low. Therefore, it is very meaningful to find a drug target to inhibit the occurrence and development of tumors. In recent years, autophagy or self-phagocytosis has become a hotspot of medical research. It can remove damaged or excess organelles from cells, be survived from external environmental pressures, and affect the survival, metabolism, differentiation, aging and death of tumor cells. The biological behavioral process plays important roles in remodeling and maintaining the dynamic balance of cell survival, especially in close relations to tumor development. Autophagy is also a double-edged sword in effect on a single tumor cell and the entire tumor. When the autophagy of the tumor cells is abnormal, or the cells are unable to remove the damaged substances in time under the conditions of hypoxia and nutrient deficiency, autophagy is beneficial to the proliferation and survival of the tumor cells. Contrarily, moderate autophagy acts as an inhibitor of tumors and has an anti-tumor effect. Traditional Chinese medicine (TCM) has a long history of controlling tumors, with the advantages of low toxicity and multiple targets. Through overall and local therapies, it has a comprehensive therapeutic effect in cancer. With the deepening of tumor autophagy research, in addition to western medicine researches on tumor autophagy, there are also domestic and foreign researches on the autophagy in single herb and TCM compounds. The latest insights into the molecular mechanism of autophagy have led to the discovery of potential drug targets. At the same time, TCM researches have made some progress in tumor autophagy. The authors review the research progress of autophagy in TCM and the research progress of effect of TCM in regulating tumor autophagy, in the hopes to provide useful reference for effect of TCM in the treatment of autophagy.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the impact of dampness-heat (DH) on the development of mammary tumors in 7,12-dimethylbenz(a)anthracene (DMBA)-induced rats.</p><p><b>METHODS</b>Forty rats were randomly divided into 3 groups in a randomized block design, including the control group (n=13), DMBA group (n=14), and DMBA plus DH group (n=13). Rats in the DMBA group and DMBA plus DH group were intragastrically administrated with DMBA (100 mg/kg) for twice, once per week, while rats in the control group were treated with equivalent volumes of sesame oil. After DMBA administration, rats in the DMBA plus DH group were exposed to a simulated climate chamber with ambient temperature (33.0±0.5°C) and humidity (90%±5%) for 8 weeks, 8 h per day. The body weight, time of tumor formation, and number of tumors were measured weekly to calculate tumor incidence, average latency period, average number of tumors, and average tumor weight. At the end of the experiment, the levels of matrix metalloproteinase 9 (MMP-9) and tissue inhibitor of metalloproteinases 1 (TIMP-1) in serum, and the contents of tumor necrosis factor-α (TNF-α) and interleukin (IL)-1β in serum and tumor tissue were measured, respectively. Some tumor tissues were processed for hematoxylin-eosin staining to determine the histopathological changes.</p><p><b>RESULTS</b>Compared with DMBA, DMBA plus DH significantly increased the average number of tumors, average tumor weight, levels of serum MMP-9, TIMP-1, TNF-α and IL-1β, and contents of tumor tissue TNF-α and IL-1β (P<0.05 or P<0.01).</p><p><b>CONCLUSION</b>DH could accelerate the development of mammary tumors through increasing the expressions of MMP-9, TIMP-1, TNF-α and IL-1β in DMBA-induced rats.</p>