Objective(s): Resistance to medications is one of the main complications in chemotherapy of cancer. It has been shown that some multidrug resistant cancer cells indicate more sensitivity against cytotoxic effects of TNF-α compared to their parental cells. Our previous findings indicated vulnerability of the mitoxantrone-resistant breast cancer cells MCF-7/MX to cell de...

The human ATP-binding cassette superfamily G (White) member 2 (ABCG2) gene and its murine homologue breast cancer resistance protein 1 (Bcrp1) are recently described ATP-binding cassette transporters associated with drug resistance in tumor cell lines, including the MCF-7 cell line, selected for its resistance to mitoxantrone (MCF-7/ MitoR). Infection of MCF-7 cells with the retroviral vector c...

Peroxiredoxins are thiol-specific antioxidant proteins whose expression is elevated in several cancers. We compared the expression and function of Prdx1 and Prdx6 between the MCF-7 mammary adenocarcinoma cell line and the noncancerous MCF-10A cell line. We found elevated Prdx1 expression in MCF-7 cells and comparable expression of Prdx6. Suppression of Prdx1 and/or Prdx6 resulted in a modest in...

A mitoxantrone-resistant human MCF-7 breast cancer subline (MCF/MX) which is approximately 4000-fold resistant to mitoxantrone was isolated by serial passage of the parental wild-type MCF-7 cells (MCF/WT) in stepwise increasing concentrations of drug. MCF/MX cells were also approximately 10-fold cross-resistant to doxorubicin and etoposide but were not cross-resistant to vinblastine. Intracellu...

Previous studies have demonstrated elevated levels of protein kinase C (PKC) activity in multidrug-resistant human breast carcinoma MCF-7/ADR cells compared to control drug-sensitive MCF-7/WT cells (R.L. Fine, J. Patel, and B.A. Chabner, Proc. Natl. Acad. Sci. USA, 85:582-586, 1988). In our present studies, immunohistochemical localization analysis using a polyclonal PKC antibody recognizing th...

We have reported that nordihydroguaiaretic acid (NDGA) inhibits the tyrosine kinase activities of the IGF-1 receptor (IGF-1R) and the HER2 receptor in breast cancer cells. Herein, we studied the effects of NDGA on the growth of estrogen receptor (ER) positive MCF-7 cells engineered to overexpress HER2 (MCF-7/HER2-18). These cells are an in vitro model of HER2-driven, ER positive, tamoxifen resi...

AIM To compare the molecular profile and cell cycle of sensitive and resistant to doxorubicin MCF-7 breast cancer cells upon exposition to conventional or liposome-encapsulated forms of doxorubicin. METHODS capital EM, Cyrilliccapital TE, Cyrilliccapital TE, Cyrillic-test, immunocytochemistry, flow cytometry. RESULTS In sensitive MCF-7 cells the exposure to conventional but not liposomal fo...

AIM OF THE STUDY ATP-binding cassette super family G2 (ABCG2) is recognized as the key point of the cancer cells' resistance to chemotherapy drugs. But there have been rare reports about the relationship between ABCG2 and the invasion, migration and animal tumor formation abilities of cancer cells. We want to establish a recombinant lentiviral vector with ABCG2 overexpression, and study the vec...

Malignant Catarrhal Fever (MCF) is a fatal lymphoproliferative disease of cattle and other ungulates caused by alcelaphine herpesvirus 1 (AlHV-1) ovine 2 (OvHV-2), the main causative agents wildebeest-associated MCF (WA-MCF) sheep-associated (SA-MCF), respectively. The virus mainly spread aerosols from pregnant or newborn sheep, goats, wildebeest to susceptible animals. This case report present...

Antioxidant enzymes are critical in oxidative stress responses. Radioresistant variants isolated from MCF-7 human carcinoma cells following fractionated ionizing radiation (MCF+FIR cells) or overexpression of manganese superoxide dismutase (MCF+SOD cells) demonstrated dose-modifying factors at 10% isosurvival of 1.8 and 2.3, respectively. MCF+FIR and MCF-7 cells (exposed to single-dose radiatio...