Does socioeconomic status fully mediate the effect of ethnicity on the health of Roma people in Hungary?

BACKGROUND: Several models have been proposed to explain the association between ethnicity and health. It was investigated whether the association between Roma ethnicity and health is fully mediated by socioeconomic status in Hungary. METHODS: Comparative health interview surveys were performed in 2003-04 on representative samples of the Hungarian population and inhabitants of Roma settlements. Logistic regression models were applied to study whether the relationship between Roma ethnicity and health is fully mediated by socioeconomic status, and whether Roma ethnicity modifies the association between socioeconomic status and health. RESULTS: The health status of people living in Roma settlements was poorer than that of the general population (odds ratio of severe functional limitation after adjustment for age and gender 1.8 (95% confidence interval 1.4 to 2.3)). The difference in self-reported health and in functionality was fully explained by the socioeconomic status. The less healthy behaviours of people living in Roma settlements was also related very strongly to their socioeconomic status, but remained significantly different from the general population when differences in the socioeconomic status were taken into account, (eg odds ratio of daily smoking 1.6 (95% confidence interval 1.3 to 2.0) after adjustment for age, gender, education, income and employment). CONCLUSION: Socioeconomic status is a strong determinant of health of people living in Roma settlements in Hungary. It fully explains their worse health status but only partially determines their less healthy behaviours. Efforts to improve the health of Roma people should include a focus on socioeconomic status, but it is important to note that cultural differences must be taken into account in developing public health interventions.

TPA induces transglutaminase C and inhibits cell growth in the colon carcinoma cell line SW620.

In contrast to most other systems, TPA induced TGc activity and protein in SW620 human colon carcinoma cells. This induction was accompanied by cell growth inhibition and increased apoptosis. The general protein kinase-C inhibitor GF-109203X blocked the induction of TGc by TPA, whereas the specific inhibitor of the PKC alpha isoform, the indocarbazole Go6976, reduced it by 40%. These PKC inhibitors had similar inhibitory effects on TPA increased apoptosis and inhibition of cell growth, suggesting that the observed actions of TPA are mediated by PKC, and a close connection between TGc activity, increased apoptosis and cell growth inhibition. We conclude that TPA may offer new approaches in the management of colon cancer cell growth.

The H-ras oncogene interferes with retinoic acid signaling and metabolism in NIH3T3 cells.

We have previously shown that retinoic acid (RA) fails to induce transglutaminase C in H-ras transformed NIH-3T3 cells. Therefore, we investigated the effect of the H-ras oncogene on the metabolism of RA and on the expression of the cellular RA-binding protein I mRNA. HPLC analysis of the media and cell extracts demonstrated that H-ras-transformed cells metabolize RA to a much lesser extent than control cells, resulting in a higher concentration of RA in H-ras cells. Although inactive in endogenous transglutaminase induction, H-ras cell-associated RA was shown to be biologically available to induce activation of a reporter construct containing a retinoid response element and in stimulating transglutaminase activity in nontransfected cells. Cellular RA-binding protein I mRNA, supposedly involved in RA storage, was significantly increased in the H-ras-transformed cells. These data demonstrate that, even though H-ras-transformed cells accumulate up to 20 fold the concentration of RA as NIH-3T3 cells, they fail to show transglutaminase induction, suggesting that H-ras interferes with signal transduction by RA.

Differential regulation by anti-tumor-promoting 12-deoxyphorbol-13-phenylacetate reveals distinct roles of the classical and novel protein kinase C isozymes in biological responses of primary mouse keratinocytes.

12-Deoxyphorbol-13-phenylacetate (dPP) is the prototype for a new class of phorbol derivatives that function as protein kinase C (PKC) activators with potent anti-tumor-promoting activity. To explore the mechanism of action of dPP, we have conducted detailed analyses of the translocation and down-regulation patterns of individual PKC isozymes in mouse primary keratinocytes upon dPP treatment. PKC-alpha, -delta, and -epsilon were very quickly (within 2-5 min) translocated from the soluble fraction to the Triton X-100-soluble particulate fraction. PKC-delta and -epsilon were translocated with 2 orders of magnitude higher potency than was PKC-alpha. After translocation, PKC-alpha, -delta, -eta, and -epsilon were down-regulated; the down-regulation of PKC-epsilon contrasts with its retention after phorbol-12-myristate-13-acetate or bryostatin treatment. As was the case with translocation, dPP down-regulated the novel PKC isozymes (delta, epsilon, and eta) with 2 orders of magnitude higher potency (ED50, about 1-2 nM), compared with PKC-alpha (ED50, about 100 nM). dPP induced transglutaminase activity, ornithine decarboxylase activity, and cornification with potencies similar to that for PKC-alpha translocation. On the other hand, dPP caused inhibition of EGF binding with a potency similar to that for the translocation of the novel PKC isozymes. Although the generality of its selectivity in different cell types remains to be determined, at least in keratinocytes dPP is a powerful tool for dissecting the involvement of the classical and novel PKC isozymes in biological responses. The unique regulatory pattern of PKC-epsilon could contribute to the anti-tumor-promoting activity of dPP.

Transformation of NIH3T3 cells with ras oncogenes abrogates the retinoic acid induction of tissue transglutaminase.

Retinoic acid greatly increases enzyme activity and mRNA expression of the tissue-type transglutaminase enzyme in NIH3T3 cells. This response is blocked in cells transformed with activated H-ras, K-ras or N-ras oncogenes, but not in pSVneo vector transfected cells. Lack of induction by RA of the tissue-type TGase in these ras-transformed fibroblasts suggests intersecting pathways between retinoid action and the ras oncogene.