The Role of EGFR, Hepatocyte Growth Factor Receptor (c-Met), c-ErbB2 (HER2-neu) and Clinicopathological Parameters in the Pathogenesis and Prognosis of Chordoma

Objective: Chordoma is a rare malignant bone tumor with a poor outcome. Although radiotherapy and gamma knife surgery have been used for treatment, providing a cure for the tumor is not easy, because of the frequent recurrences. Molecular targeted therapy against tyrosine kinases has been effective in the treatment of malignancies such as breast and lung cancers and brain tumors. We aimed to analyse the histopathological features of chordomas and the immunoexpression profiles of the three receptor tyrosine kinases of EGFR, c-Met and c-Erb-B2 in chordomas. We have correlated these results with recurrence and overall survival status of the patients. Material and Method: We studied 49 chordoma patients in order to evaluate the histopathological features and immunohistochemical stainings by EGFR, c-Met and c-ErbB2 antibodies. Of the 49 patients, follow up data was available for 40 patients. Clinical data of the patients were correlated with histopathological features and survival analysis was performed. Results: The immunostaining rate by EGFR and c-Met was 73.5% and 12.2% respectively. None of the cases showed immunoreactivity by c-ErbB2 (0%). Of the 40 cases, 17 cases showed recurrences. EGFR expression was detected in 14 recurrent (14/17) and 17 non-recurrent cases (17/23). Four of the 17 recurrent cases (4/17) were positive by c-Met, while none of the non-recurrent cases (0/23) were positive by this antibody. Significantly, all cases with positive c-Met expression showed recurrences (p<0.05). Conclusion: Our study indicates that EGFR expression is detected in the majority of chordoma cases. c-Met expression can be used as a prognostic indicator for chordoma

ERİTROİD HİPOPLAZİ GELİŞEN BİR PEDİATRİK MYELODİSPLASTİK SENDROM OLGUSU : OLGU SUNUMU

MDS, displastik ve inefektif kan hücre üretimi ile giden akut lösemiye dönüşüm riski yüksek multipotent kök hücre bozukluğu ile karakterize bir hastalık grubudur

Controlled release of imatinib mesylate from PLGA microspheres inhibit craniopharyngioma mediated angiogenesis

Poly(lactic-co-glycolic acid) microspheres loaded with imatinib mesylate has been developed as a new therapeutic strategy to prevent craniopharyngioma recurrence. Microspheres composed of different lactic/glycolic acid ratios, molecular weights and drug compositions were synthesized and loaded with imatinib mesylate by modified double-emulsion/solvent evaporation technique and subsequently characterized by particle-size distribution, scanning electron microscopy, encapsulation efficiency and in vitro drug release. Inhibitory potential of imatinib containing microspheres on tumor neovascularization was investigated on craniopharyngioma tumor samples by rat cornea angiogenesis assay. Results showed that microspheres in different LA:GA ratios [LA:GA 50:50 (G50), 75:25 (G25), 85:15 (G15)] considerably reduced neovascularization induced by recurrent tumor samples in an in vivo angiogenesis assay (P < 0.01). Our data indicate that local delivery of imatinib mesylate to the post-surgical tumoral cavity using biodegradable microspheres may be a promising biologically selective approach to prevent the recurrence of craniopharyngiomas, via inhibition of neovascularization