Caffeic acid phenethyl ester reverses doxorubicin resistance in breast cancer cells via lipid metabolism regulation at least partly by suppressing the Akt/mTOR/SREBP1 pathway.

Chemotherapy is one of the common treatment methods for breast cancer, but chemoresistance is a severe challenge. Caffeic acid phenethyl ester (CAPE) is an active ingredient of propolis extract and has been shown to have a variety of beneficial effects, and its potential as a treatment for breast cancer is worth exploring. The effects of CAPE on doxorubicin (DOX) resistance were determined by cell counting kit-8 (CCK-8) assay, colony-formation assay, and flow cytometry. Oil Red O staining and the detection of free fatty acids, triglycerides, phospholipids, and cholesterol were performed to assess the status of lipid metabolism. Quantitative polymerase chain reaction (qPCR) and western blotting were applied to investigate the molecules involved in lipid metabolism and the protein kinase B (Akt)/mammalian target of rapamycin (mTOR)/sterol regulatory element binding protein 1 (SREBP1) pathway. CAPE treatment reversed DOX resistance in breast cancer cells and suppressed their lipid metabolism. In addition, CAPE combined with DOX remarkably suppressed SREBP1 expression in part by inhibiting Akt/mTOR pathway activation. Furthermore, by inhibiting lipid metabolism, partly via the Akt/mTOR/SREBP1 pathway, CAPE ultimately reversed DOX resistance in breast cancer. Our results suggest that CAPE treatment reversed DOX resistance in breast cancer cells, at least in part by inhibiting Akt/mTOR/SREBP1 pathway-mediated lipid metabolism, indicating that CAPE may be an effective substance to assist in the treatment of breast cancer.

[Assessment of rice achievable productivity and its application in rice production management division: a case study in Fuyang County of Zhejiang Province, East China].

Rice productivity is the key factor affecting rice production and its sustainable development. Based on the gradation of cultivated land quality at county-level, this paper evaluated the rice productivity in Fuyang County of Zhejiang Province, and, through selected sampling field investigation and according to the land productivity index of paddy field quality, a model for assessing rice achievable productivity was established, aimed to analyze the regional rice productivity and its achievable productivity. In the study area, there was a positive correlation between the land productivity index and rice yield. For single cropping rice, its achievable productivity was 1.70 x 10(5) t, being 1.6 times of its realistic productivity (1.04 x 10(5) t). In 2009, the realistic rice productivity per unit area was 7676 kg x hm(-2), and the achievable productivity was 8831 kg x hm(-2), with a production potentiality of +15%, a big potential of rice production capacity in the county. Through the analyses of rice productivity, relative superiority of rice production scale, and its growth potential index in the villages and towns, the rice production of Fuyang County was divided into three regions, i. e., key enhancement region, optimization construction region, and development protection region.