Biomedical subjects

A Florin

Publications and source records attributed to A Florin.

9 recordsLinked to original sources

PubMed2006

[Long-term effects of environmental endocrine disruptors on male fertility].

Several epidemiologic studies have demonstrated during the last 50 years an increased incidence in testis cancer, male genital tract malformations (cryptorchidism and hypospadias) and a decrease in sperm quality in men. These three pathologies seem to be linked and to belong to the testicular dysgenesis syndrome (TDS). It was suggested that TDS is a consequence of intra-uterine exposure to environmental compounds that disrupt the metabolism of native hormones. Such substances are so called endocrine disruptors (EDs). EDs are present in our daily environment such as food and water (through the use of pesticides), cosmetics, house-care products etc. Experimental models have been carried out to (i) establish a link between EDs exposure and SDT and (ii) identify the mechanisms that are involved in. After a brief definition of EDs and having underlined the importance of the window of exposure to EDs, several mechanisms will be described such as (i) intergenerational transmission (epigenetic), (ii) programmed cell death of testicular cells, (iii) modification of the androgenic signal and (iv) role of the germ cells-nourishing cells. To conclude, we will try to propose some biomarkers that would be useful to identify the potential link between fetal exposure to anti-androgenic EDs and male testicular pathology.

Androgen Antagonists↗

PubMed2004

The Ets-1 transcription factor is involved in the development and invasion of malignant melanoma.

The Ets-1 transcription factor plays a role in tumor vascularization and invasion by regulating expression of matrix-degrading proteases in endothelial cells and fibroblasts in the tumor stroma. During early embryogenesis, Ets-1 is expressed in migrating neural crest cells from which melanocytes arise. In the present study, we analyzed Ets-1 expression in various melanocytic lesions and investigated its functional importance in malignant melanomas. We found that Ets-1 was upregulated both in vivo and in vitro in malignant melanoma, compared to benign melanocytic lesions and to primary melanocytes. Assessment of DNA-binding and transactivation assays documented a strong Ets activity in melanoma cells. Using an antisense strategy, the expression and activity of Ets-1 were reduced in the melanoma cell line Mel Im. This correlated with a diminished expression of several Ets-1 target genes known to be involved in invasion, such as MMP1, MMP3, uPA and integrin beta3. In line with these findings, the invasive potential of the melanoma cells measured in a Boyden Chamber model was reduced up to 60% after Ets-1 blockade. This can be attributed to the role of Ets-1 in transcriptional regulation of factors involved in invasion of melanoma cells. We conclude that over-expression of Ets-1 during melanoma development contributes to the malignant phenotype.

DNA, Neoplasm↗

PubMed2001

Invasive properties of serous human epithelial ovarian tumors are related to Ets-1, MMP-1 and MMP-9 expression.

The invasive potential of serous epithelial ovarian tumors is the main factor determining their biological behaviour. In contrast to invasive serous ovarian carcinomas serous borderline tumors generally present without stromal invasion and without or non-invading peritoneal implants. Little is known about the reasons underlying these differences. In the present study we found that two matrix-degrading metalloproteinases, collagenases 1 and 4 (MMPs 1 and 9), as well as the Ets-1 transcription factor are expressed at very low levels in serous benign cystadenomas, upregulated in the fibroblastic stroma, but not in the epithelium of borderline tumors and most strongly expressed in both stromal and epithelial tumor cells of serous invasive carcinomas. Since expression of Ets-1 and of MMPs 1 and 9 are topographically related, a transcriptional regulation of both proteases by Ets-1 is suggested. Upregulation of MMPs 1 and 9 within fibroblastic stromal cells of borderline tumors might be related to matrix remodelling and additional expression of both enzymes by the neoplastic cells of invasive carcinomas could then allow invasive propagation. The different expression patterns might supports the view, that no transition of serous borderline tumors into invasive carcinomas occurs.

3T3 Cells↗

PubMed1993

Abnormal sympathetic skin response in patients with autoimmune vitiligo and primary autoimmune hypothyroidism.

The sympathetic skin response was studied in 21 patients with autoimmune vitiligo or hypothyroidism or both. No response to stimulation was found in 6 patients, but 4 with both diseases showed abnormal results. Sympathetic skin response is useful in evaluating sudomotor activity of the autonomic nervous system, and it is concluded that patients with autoimmune vitiligo, autoimmune hypothyroidism and especially those with both diseases show evidence of sudomotor dysfunction.

Autoimmune Diseases↗

PubMed1974