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Piprek R.P.,Jagiellonian University | Pecio A.,Jagiellonian University | Kubiak J.Z.,Institute of Genetics and Development of Rennes | Kubiak J.Z.,University of Rennes 1 | Szymura J.M.,Jagiellonian University
Reproduction | Year: 2012

Sex hormones are essential for sexual differentiation and play a key role in the development of gonads in amphibians. The goal of this study was to evaluate the influence of exogenous sex steroids, testosterone, and 17b-estradiol (E2) on development of gonads in five anuran species differing in their evolutionary positions, sex determination, and mode of gonadogenesis. We found that in two closely related species of fire-bellied toad, Bombina bombina and Bombina variegata, testosterone and E2 exposure results in sex reversal as well as intersex and undifferentiated gonads. Similarly, sex reversal was observed in Hyla arborea after exposure to male or female sex steroids. Xenopus laevis was sensitive to E2 but only moderately to testosterone. In Bufo viridis, treatment with either sex hormone provoked a developmental delay in gonads and Bidder's organs. Therefore, susceptibility to hormonal sex reversal appeared species dependent but unrelated to genetic sex determination and the type of gonadogenesis.We also found that the onset of sex steroid exposure influences gonad differentiation and the meiotic status of the germ cells depends on their location within the gonad. Our findings reveal differential sensitivity of amphibians to testosterone and E2, establishing a hierarchy of sensitivity to these hormones among different anuran species. © 2012 Society for Reproduction and Fertility.

Ferchichi I.,Laboratory of Genetics | Kourda N.,Charles Nicolle Hospital | Sassi S.,Oncology Institute of Saleh Azaiez | Romdhane K.B.,Oncology Institute of Saleh Azaiez | And 4 more authors.
Disease Markers | Year: 2012

We investigate the expression and localization of the tumor suppressor protein pVHL as well as the oncoprotein Aurora A kinase in kidney cancer. Both Aurora A kinase and pVHL protein status were evaluated using immunohistochemistry. The Aurora A expression is correlated with the Fuhrman grade and the TNM stage, while the pVHL expression is correlated with the capsule rupture and the TNM stage. Aurora A kinase expression increases in malignant tissue comparing to the non-malignant one. And there is a decrease in pVHL expression from the adjacent healthy tissues to the tumor's ones. The two kinds of opposite tumor profiles display significant distribution difference according to TNM stages. It could be proposed that the absence of Aurora A protein associated with a strong expression of pVHL in clear cells kidney carcinoma are of good prognosis for the disease. © 2012-IOS Press and the authors. All rights reserved.

Ferchichi I.,Laboratory of Genetics | Sassi Hannachi S.,Oncology Institute of Saleh Azaiez | Baccar A.,Laboratory of Genetics | Marrakchi Triki R.,Laboratory of Genetics | And 4 more authors.
Disease Markers | Year: 2013

Aurora A kinase is overexpressed in many cancers but the status of this protein in the breast cancer often varies. We investigate the expression and localization of Aurora A protein in relation with tumor emergence and progression in breast cancer. Aurora A kinase status was evaluated in 107 patients using immunohistochemistry. The experimental findings showed that high expression of the Aurora A protein was correlated with elevated nuclear grade, low expression of progesterone receptor and positive nodal status. The experimental results showed also that the localization of this kinase shifts from cytoplasm in non malignant adjacent tissue to both cytoplasmic and nuclear compartments in tumoral tissue, suggesting an oncogenic role of the nuclear accumulation. We have, furthermore, detected the overexpression of this protein in non malignant adjacent tissue. The expression of the Aurora A kinase in non malignant tissue may represent an earlier diagnosis tool for breast cancer. © 2013 - IOS Press and the authors. All rights reserved.

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