three major flavonoid fractions were separated from a methanol extract of calendula officinalis flowers by preparative tlc. these fractions were evaluated for the inhibition of parent and tamoxifen resistant t47d human breast cancer cells. we also examined the effect of quercetin and isorhamnetin on the growth of parent and resistant t47d cells in the presence and absence of tamoxifen. it was f...

Breast cancer is one of the most common malignancies among women. Although chemotherapy remains a major therapeutic approach to treat cancers, drug therapy often fails for several reasons, particularly the drug resistance. Resistance to multiple chemotherapeutic agents is one of the most important problems in the treatment of different types of cancers. Therefore, in this study a resistant sub ...

Breast cancer is one of the most common malignancies among women. Although chemotherapy remains a major therapeutic approach to treat cancers, drug therapy often fails for several reasons, particularly the drug resistance. Resistance to multiple chemotherapeutic agents is one of the most important problems in the treatment of different types of cancers. Therefore, in this study a resistant sub ...

indirect evidence suggests that estrogen is involved in the etiology of breast cancer. estrogen is also thought to modulate nitric oxide (no) in human breast tumor tissue via regulation of inducible nitric oxide synthase (inos). objectives of this study were to determine whether estradiol (e2) affects inos expression level in breast cancer cells and to study the effect of various concentrations...

breast cancer is one of the most common malignancies among women. although chemotherapy remains a major therapeutic approach to treat cancers, drug therapy often fails for several reasons, particularly the drug resistance. resistance to multiple chemotherapeutic agents is one of the most important problems in the treatment of different types of cancers. therefore, in this study a resistant sub ...

Objective(s): Breast cancer remains a global challenge, and further chemopreventive therapies are still immediately required. Emerging evidence has revealed the potent anti-cancer effects of biguanides, Metformin (MET) and phenformin (PHE). Thus, to explore an efficient chemopreventive strategy for breast cancer, the antiproliferative effects of the combination of MET and PHE against breast can...

objective(s):micrornas (mirnas) are a class of short rnas that control the biological processes including cell proliferation, apoptosis and development. aberrant expression of mirnas was determined in the different stages of tumor development and metastasis. to study the effect of silibinin on mirnas expression, we evaluated quantitative expression of mir-21 and mir-155 as two oncomirs and seve...

Indirect evidence suggests that estrogen is involved in the etiology of breast cancer. Estrogen is also thought to modulate nitric oxide (NO) in human breast tumor tissue via regulation of inducible nitric oxide synthase (iNOS). Objectives of this study were to determine whether estradiol (E2) affects iNOS expression level in breast cancer cells and to study the effect of various concentrations...

Indirect evidence suggests that estrogen is involved in the etiology of breast cancer. Estrogen is also thought to modulate nitric oxide (NO) in human breast tumor tissue via regulation of inducible nitric oxide synthase (iNOS). Objectives of this study were to determine whether estradiol (E2) affects iNOS expression level in breast cancer cells and to study the effect of various concentrations...

The role of antioxidants in prevention and treatment of cancers have been reported by several studies. In our investigation we studied the effects of ascorbic acid, ?-tocopherol, and sodium selenite on proliferation of two breast cancer cell lines: T47D (estrogen-receptor positive) and MDA-MB-231 (estrogen-receptor negative). We also used 17-?-estradiol as positive control for proliferation of ...