Biological behavior of ovarian carcinomas might be the result of cellular diversity existing in tumor tissue, which consists of differentiated and undifferentiated cells showing stem cells biological properties and function. We examined correlation between p53 protein phosphorylated at serine 20 (p-p53(Ser20)) and CD133, SOX2, Notch1 expression, in order to reveal p-p53(Ser20) stemness function in ovarian cancer. p-p53(Ser20), CD133, Notch1, SOX2 expression was analyzed on 104 ovarian carcinomas using immunohistochemical staining. The positive correlation between p53 and p-p53(Ser20) (p=0.02), p53 and SOX2 (p=0.02), p-p53(Ser20) and Notch1 (p=0.03), p-p53(Ser20) and CD133 (p=0.01) expression was observed in ovarian carcinomas. The parallel expression of p-p53(Ser20)/CD133, p-p53(Ser20)/Notch1 reflecting co-expression of these proteins in single carcinoma cell, and p-p53(Ser20)/SOX2 expression was associated with advanced stage and p-p53(Ser20)/ Notch1, p53/SOX2, p-p53(Ser20)/SOX2 parallel expression correlated with high tumor grade. The correlation between p-p53(Ser20) and CD133, Notch1, SOX2 expression and clinical parameters indicate, that malignancy and biological behavior of ovarian carcinomas depend on interaction between p-p53(Ser20) and carcinoma stem cells biomarkers expression.

The presented study aimed to evaluate in vitro the effectiveness of improvement standard chemotherapy with bleomycin by electroporation in two various ovarian cancer cell lines. Two human ovarian cell lines OvBH-1 and SKOV-3 were used. The lines were selected because of their resistance to several therapeutic methods. As anticancer drug we use range of concentrations of bleomycin. In EP and ECT experiments different voltage values: from 0 to 1200 V/cm, 8 pulses with duration of 100μs and intervals between pulses 1s long were used. The cells viability after applied treatments was evaluated by MTT assay. The expression of heat shock proteins - HSP27 was examined by immunocytochemical ABC method.The cytotoxicity with different concentrations of bleomycin alone was not significantly decrease in both cell lines. It confirms resistance of these cells to conventional chemotherapy. The highest decrease of cell proliferation was observed after EP with bleomycin after 48h of incubation for 1000 V/cm. The intensity of expression of small heat shock proteins HSP27 slightly increased after ECT in both treated cell lines, in particular in OvBH-1. The presented study indicated that application of electroporation may effectively enhance chemotherapy with bleomycin, particularly in the case of treating ovarian cancer resistant to standard therapy.

Epidermal growth factor receptor (EGFR) and estrogen receptor (ER) status were immunohistochemically evaluated in 80 primary ductal breast carcinomas. The comparison between EGFR status and tumor grading, tumor size, lymph node involvement and age of patients was performed. EGFR expression was found in 87.5% of carcinoma samples and 46.3% of tumors were positive for ER staining. The inverse relationship between EGFR and ER expression was confirmed and it was evident that a high concentration of EGFR exceeding 25% of a tissue section may inhibit or significantly limit the ability to express ERs. EGFR presence was significantly associated with poorly differentiated tumors. No correlation was found between EGFR positivity and tumor size, lymph node involvement or age of patients. Our results indicate that EGFR status does not seem to be a valuable independent prognostic indicator, but that the combination of EGFR positivity (above 25% of a tissue section) accompanied by a low or undetectable level of ER expression should be considered as a potential marker of a poor prognosis in patients with ductal breast carcinoma.