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Background: One major concern in the treatment of cancer patients during chemotherapy is drug resistance. Here we investigated the effects of soy isoflavone extracts alone or in combination with Docetaxel on the drug resistance, angiogenesis, apoptosis, and tumor volume in mouse 4T1 breast tumor model. Methods: Sixty female BALB/c mice were randomly divided into 4 groups: control, dietary soy isoflavone extract [Iso, 100 mg/kg diet (0.01%)], Docetaxel (10 mg/kg) injection, and the combination of dietary soy isoflavone extract and intravenous Docetaxel injection (Docetaxel + Iso). One week after the third injection, the breast tumors of eight mice from each group were excised to analyze NF-κBp65′ vascular endothelial growth factor receptor-2 (VEGFR2) and Pgp gene and protein expressions and the other seven mice were monitored for survival rate analysis until they died. Results: NF-κBp65 gene and protein expressions were significantly lower in the Docetaxel + Iso group in comparison with that of the Docetaxel group. VEGFR2 protein expression in the Docetaxel + Iso and Iso groups was significantly lower than that of the Docetaxel group. Conclusion: These findings may indicate that the combined use of isoflavone extracts together with chemotherapeutic agents has more efficient anti-carcinogenic effects than their individual use. [ABSTRACT FROM AUTHOR]

Background: Emergence of drug resistance has brought major problems in chemotherapy. Using nutrients in combination with chemotherapy could be beneficial for improvement of sensitivity of tumors to drug resistance. Soybean-derived isoflavones have been suggested as chemopreventive agents for certain types of cancer, particularly breast cancer. In this study, the synergistic effects of soy isoflavone extract in combination with docetaxel in murine 4T1 breast tumor model were investigated. Methods: In this study, mice were divided into 4 groups (15 mice per group) of control, the dietary Soy Isoflavone Extract (SIE, 100 mg/kgdiet), the Docetaxel (DOCE, 10 mg/kg) injection and the combination of dietary soy isoflavone extract and intravenous docetaxel injection (DOCE+SIE). After 3 injections of docetaxel (once a week), 7 mice were sacrificed to analyze MKI67 gene and protein expressions and the rest were monitored for diet consumption, tumor growth and survival rates. Results: In DOCE+SIE group, diet consumption was significantly higher than DOCE group. While lifespan showed a trend towards improvement in DOCE+SIE group, no significant difference was observed among the 4 studied groups. Tumor volume was not significantly affected in treated groups. A lower but not significant MKI67 protein expression was detected in western blot in DOCE+SIE group. The mRNA expression was not significantly different among groups. Conclusion: The results suggest that the combination of soy isoflavone as an adjunct to docetaxel chemotherapy can be effective in improving diet consumption in breast cancer. [ABSTRACT FROM AUTHOR]

Objective: To investigate the expression and localization of vitamin D3 receptor (VDR) in reproductive organs of cycling mice. Design: Experimental animal study. Setting: Academic research center. Animal(s): Mature (8 to 12 weeks old) cycling female Balb/c mice. Intervention(s): Reproductive tissue, including endometrium, ovary, and fallopian tubes, were collected at each phase of estrous cycle to examine VDR expression. Main Outcome Measure(s): Expression of VDR messenger (mRNA) was determined by semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR). The presence and localization of VDR was assessed by immunohistochemistry, and the intensity of VDR expression was quantified with U.S. National Institutes of Health image-analysis software. Result(s): The VDR mRNA was expressed in the endometrium throughout the estrous cycle. The relative expression of VDR mRNA at the estrus phase was more prominent compared with the other phases. Immunohistochemical analysis revealed that dendritic cells, macrophages, and luminal and glandular epithelial cells of the endometrium, granulosa, and cumulus oophorus cells of the ovary and fallopian epithelial cells strongly express VDR, particularly during the estrus phase. Conclusion(s): Our findings have demonstrated, for the first time, that VDR is present and differentially expressed in murine reproductive organs throughout the estrous cycle. Further studies are required to evaluate the functional immunologic role of VDR. [Copyright &y& Elsevier]