Remodeling of extracellular matrix by normal and tumor-associated fibroblasts promotes cervical cancer progression

Background: Comparison of tissue microarray results of 29 cervical cancer and 27 normal cervix tissue samples using immunohistochemistry revealed considerable reorganization of the fibrillar stroma of these tumors. Preliminary densitometry analysis of laminin-1, α -smooth muscle actin (SMA) and fibronectin immunostaining demonstrated 3.8-fold upregulation of laminin-1 and 5.2-fold increase of SMA in the interstitial stroma, indicating that these proteins and the activated fibroblasts play important role in the pathogenesis of cervical cancer. In the present work we investigated the role of normal and tumor-associated fibroblasts. Methods: In vitro models were used to throw light on the multifactorial process of tumor-stroma interaction, by means of studying the cooperation between tumor cells and fibroblasts. Fibroblasts from normal cervix and cervical cancers were grown either separately or in co-culture with CSCC7 cervical cancer cell line. Changes manifest in secreted glycoproteins, integrins and matrix metallo-proteases (MMPs) were explored. Results: While normal fibroblasts produced components of interstitial matrix and TGF- β 1 that promoted cell proliferation, cancer-associated fibroblasts (CAFs) synthesized ample amounts of laminin-1. The following results support the significance of laminin-1 in the invasion of CSCC7 cells: 1.) Tumor-associated fibroblasts produced more laminin-1 and less components of fibrillar ECM than normal cells; 2.) The production of laminin chains was further increased when CSCC7 cells were grown in co-culture with fibroblasts; 3.) CSCC7 cells were capable of increasing their laminin production; 4.) Tumor cells predominantly expressed integrin α 6 β 4 laminin receptors and migrated towards laminin. The integrin profile of both normal and tumor-associated fibroblasts was similar, expressing receptors for fibronectin, vitronectin and osteopontin. MMP-7 secreted by CSCC7 cells was upregulated by the presence of normal fibroblasts, whereas MMP-2 produced mainly by fibroblasts was activated in the presence of CSCC7 cells. Conclusions: Our results indicate that in addition to degradation of the basement membrane, invasion of cervical cancer is accomplished by the remodeling of the interstitial stroma, which process includes decrease and partial replacement of fibronectin and collagens by a laminin-rich matrix

Társadalmi integráció és az integráló közoktatás jogosultságok, méltányosságok érvényesülése a köznevelési struktúrában : Esetismertetések egy vidéki kisváros életéből

Dolgozatommal arra vállalkozom, hogy a nemzetközi és hazai társadalmi integrációs és esélyegyenlőségi törekvések hullámaiból beljebb lépve a mai magyar köznevelés mindennapjaiba, felvillantsak olyan jelenségeket, melyek tanulságait érdemes lehet visszaáramoltatni a jogalkotás és a fogyatékosságügyi politika területére

Two ways of epigenetic silencing of TFPI2 in cervical cancer.

ObjectiveComparison of human mRNA microarray results from tumor-associated and normal cervical fibroblasts revealed significant TFPI2 downregulation in tumor-associated fibroblasts isolated from cervical cancer, indicating that TFPI2 downregulation may play an important role in the pathogenesis of the disease. In the present work, we investigated the mechanism of TFPI2 downregulation in tumor-associated fibroblasts and tumor cells.MethodsIn vitro models of monocultures and co-cultures were established with tumor cells and fibroblasts to explore the changes of TFPI-2 expression and epigenetic modifications of the TFPI2 gene.ResultsThe TFPI2 gene was hypermethylated only in tumor cells. Reduction of TFPI-2 protein levels in tumor-associated fibroblasts, although the gene was not methylated, suggested alternative regulatory mechanisms of gene expression, such as inhibition by microRNAs. The expression pattern of miR-23a, a gene thought to inhibit TFPI2 translation, showed changes strongly correlated to detected TFPI-2 protein alterations. Transfections with miR-23a mimics resulted in a decrease of TFPI-2 protein expression whereas miR-23a inhibitors increased the TFPI-2 amount. Due to downregulation of miR-23a expression by HPV in cancer cells, TFPI2 was silenced by promoter methylation. In contrary, miR-23a was active in HPV-free fibroblasts and inactivated TFPI2.ConclusionThese results indicate dual epigenetic inhibition of TFPI2 on the transcription level by promoter methylation in cancer cells and on the translation level by miR-23a in tumor-associated fibroblasts. As a consequence, inactivation of the TFPI2 gene plays a strategic role in the progression of cervical cancer

Expression and Prognostic Examination of Heat Shock Proteins (HSP 27, HSP 70, and HSP 90) in Medulloblastoma

Expression of heat shock proteins (HSPs) is of prognostic significance in several tumor types. HSP expression levels were determined in medulloblastomas and tested whether HSPs expression was associated with prognostic parameters. Expression of antiapoptotic HSP 27, HSP 70, and HSP 90 was investigated by immunohistochemistry, on paraffin-embedded sections from 65 patients. Expression of HSPs was validated on internal vascular controls and by Western blotting analysis. Sample evaluation was based on the estimated percentage of HSP positive tumor cells. For survival analysis Kaplan-Meier method, for statistical analysis χ2 test, univariate analysis, and log rank test were applied. Expression of HSPs varied in medulloblastomas. On the basis of the average expression rate of HSPs, at HSP 27 and HSP 90 with a 10% cut off, and at HSP 70 with a 70% cut off 2 groups were created. The amount of expression of any of the HSP types was not significantly associated with known prognostic factors (age of patient, extent of resection, presence of metastasis) and histologic subtype. After an average follow-up period of 4.30 years, no significant difference was observed in survival depending on the expression of HSP 27 or HSP 70 or HSP 90. The high expression of HSPs indicates that these proteins are potential therapeutic targets