Inhibition of TNFalpha in vivo prevents hyperoxia-mediated activation of caspase 3 in type II cells

BACKGROUND: The mechanisms during the initial phase of oxygen toxicity leading to pulmonary tissue damage are incompletely known. Increase of tumour necrosis factor alpha (TNFalpha) represents one of the first pulmonary responses to hyperoxia. We hypothesised that, in the initial phase of hyperoxia, TNFalpha activates the caspase cascade in type II pneumocytes (TIIcells). METHODS: Lung sections or freshly isolated TIIcells of control and hyperoxic treated rats (48 hrs) were used for the determination of TNFalpha (ELISA), TNF-receptor 1 (Western blot) and activity of caspases 8, 3, and 9 (colorimetrically). NF-kappaB activation was determined by EMSA, by increase of the p65 subunit in the nuclear fraction, and by immunocytochemistry using a monoclonal anti-NF-kappaB-antibody which selectively stained the activated, nuclear form of NF-kappa B. Apoptotic markers in lung tissue sections (TUNEL) and in TIIcells (cell death detection ELISA, Bax, Bcl-2, mitochondrial membrane potential, and late and early apoptotic cells) were measured using commercially available kits. RESULTS: In vivo, hyperoxia activated NF-kappaB and increased the expression of TNFalpha, TNF-receptor 1 and the activity of caspase 8 and 3 in freshly isolated TIIcells. Intratracheal application of anti-TNFalpha antibodies prevented the increase of TNFRI and of caspase 3 activity. Under hyperoxia, there was neither a significant change of cytosolic cytochrome C or of caspase 9 activity, nor an increase in apoptosis of TIIcells. Hyperoxia-induced activation of caspase 3 gradually decreased over two days of normoxia without increasing apoptosis. Therefore, activation of caspase 3 is a temporary effect in sublethal hyperoxia and did not mark the "point of no return" in TIIcells. CONCLUSION: In the initiation phase of pulmonary oxygen toxicity, an increase of TNFalpha and its receptor TNFR1 leads to the activation of caspase 8 and 3 in TIIcells. Together with the hyperoxic induced increase of Bax and the decrease of the mitochondrial membrane potential, activation of caspase 3 can be seen as sensitisation for apoptosis. Eliminating the TNFalpha effect in vivo by anti-TNFalpha antibodies prevents the pro-apoptotic sensitisation of TIIcells

Brain-type and liver-type fatty acid-binding proteins: new tumor markers for renal cancer?

BACKGROUND: Renal cell carcinoma (RCC) is the most common renal neoplasm. Cancer tissue is often characterized by altered energy regulation. Fatty acid-binding proteins (FABP) are involved in the intracellular transport of fatty acids (FA). We examined the level of brain-type (B) and liver-type (L) FABP mRNA and the protein expression profiles of both FABPs in renal cell carcinoma. METHODS: Paired tissue samples of cancerous and noncancerous kidney parts were investigated. Quantitative RT-PCR, immunohistochemistry and western blotting were used to determine B- and L-FABP in tumor and normal tissues. The tissue microarray (TMA) contained 272 clinico-pathologically characterized renal cell carcinomas of the clear cell, papillary and chromophobe subtype. SPSS 17.0 was used to apply crosstables (chi2-test), correlations and survival analyses. RESULTS: B-FABP mRNA was significantly up-regulated in renal cell carcinoma. In normal tissue B-FABP mRNA was very low or often not detectable. RCC with a high tumor grading (G3 + G4) showed significantly lower B-FABP mRNA compared with those with a low grading (G1 + G2). Western blotting analysis detected B-FABP in 78% of the cases with a very strong band but in the corresponding normal tissue it was weak or not detectable. L-FABP showed an inverse relationship for mRNA quantification and western blotting. A strong B-FABP staining was present in 52% of the tumor tissues contained in the TMA. In normal renal tissue, L-FABP showed a moderate to strong immunoreactivity in proximal tubuli. L-FABP was expressed at lower rates compared with the normal tissues in 30.5% of all tumors. There was no correlation between patient survival times and the staining intensity of both FABPs. CONCLUSION: While B-FABP is over expressed in renal cell carcinoma in comparison to normal renal tissues L-FABP appears to be reduced in tumor tissue. Although the expression behavior was not related to the survival outcome of the RCC patients, it can be assumed that these changes indicate fundamental alterations in the fatty metabolism in the RCC carcinogenesis. Further studies should identify the role of both FABPs in carcinogenesis, progression and with regard to a potential target in RCC

ADAM9 is highly expressed in renal cell cancer and is associated with tumour progression

<p>Abstract</p> <p>Background</p> <p><b>A D</b>isintegrin <b>A</b>nd <b>M</b>etalloprotease (ADAM) 9 has been implicated in tumour progression of various solid tumours, however, little is known about its role in renal cell carcinoma. We evaluated the expression of ADAM9 on protein and transcript level in a clinico-pathologically characterized renal cell cancer cohort.</p> <p>Methods</p> <p>108 renal cancer cases were immunostained for ADAM9 on a tissue-micro-array. For 30 additional cases, ADAM9 mRNA of microdissected tumour and normal tissue was analyzed via quantitative RT-PCR. SPSS 14.0 was used to apply crosstables (Fisher's exact test and χ²-test), correlations and univariate as well as multivariate survival analyses.</p> <p>Results</p> <p>ADAM9 was significantly up-regulated in renal cancer in comparison to the adjacent normal tissue on mRNA level. On protein level, ADAM9 was significantly associated with higher tumour grade, positive nodal status and distant metastasis. Furthermore, ADAM9 protein expression was significantly associated with shortened patient survival in the univariate analysis.</p> <p>Conclusion</p> <p>ADAM9 is strongly expressed in a large proportion of renal cell cancers, concordant with findings in other tumour entities. Additionally, ADAM9 expression is significantly associated with markers of unfavourable prognosis. Whether the demonstrated prognostic value of ADAM9 is independent from other tumour parameters will have to be verified in larger study cohorts.</p

ADAM9 is highly expressed in renal cell cancer and is associated with tumour progression-0

S was normalized to the geometric mean of the two reference genes PPIA and TBP. For most cases mRNA levels of the renal cell cancers laid above those of the normal tissue standard.<p><b>Copyright information:</b></p><p>Taken from "ADAM9 is highly expressed in renal cell cancer and is associated with tumour progression"</p><p>http://www.biomedcentral.com/1471-2407/8/179</p><p>BMC Cancer 2008;8():179-179.</p><p>Published online 26 Jun 2008</p><p>PMCID:PMC2442841.</p><p></p

ADAM9 is highly expressed in renal cell cancer and is associated with tumour progression-1

Apillary () and chromophobe () renal cell carcinoma with strong ADAM9 expression. Normal renal tissue with weak () and strong () ADAM9 expression.<p><b>Copyright information:</b></p><p>Taken from "ADAM9 is highly expressed in renal cell cancer and is associated with tumour progression"</p><p>http://www.biomedcentral.com/1471-2407/8/179</p><p>BMC Cancer 2008;8():179-179.</p><p>Published online 26 Jun 2008</p><p>PMCID:PMC2442841.</p><p></p

ADAM9 is highly expressed in renal cell cancer and is associated with tumour progression-3

S was normalized to the geometric mean of the two reference genes PPIA and TBP. For most cases mRNA levels of the renal cell cancers laid above those of the normal tissue standard.<p><b>Copyright information:</b></p><p>Taken from "ADAM9 is highly expressed in renal cell cancer and is associated with tumour progression"</p><p>http://www.biomedcentral.com/1471-2407/8/179</p><p>BMC Cancer 2008;8():179-179.</p><p>Published online 26 Jun 2008</p><p>PMCID:PMC2442841.</p><p></p

ADAM9 is highly expressed in renal cell cancer and is associated with tumour progression-2

Old line) revealed significantly shortened patient survival times if compared to those with low ADAM9 expression (dotted line).<p><b>Copyright information:</b></p><p>Taken from "ADAM9 is highly expressed in renal cell cancer and is associated with tumour progression"</p><p>http://www.biomedcentral.com/1471-2407/8/179</p><p>BMC Cancer 2008;8():179-179.</p><p>Published online 26 Jun 2008</p><p>PMCID:PMC2442841.</p><p></p