ABSTRACT
PURPOSE: Retinoblastoma (RB) is a malignant tumor of infancy and childhood. Unfavorable therapeutic response is still a quest in many tumors, including retinoblastoma. Hypoxic tumor microenvironment is one of the factors that determine the therapeutic response in many tumors. The purpose of this study was to determine the presence of hypoxia and its related proteins; Hypoxia inducible factor-1α (HIF-1α), Carbonic anhydrase IX (CA IX) and survivin in RB and their association with clinicopathological features. MATERIALS AND METHODS: We evaluated the expression of HIF-1α and survivin by immunohistochemistry in 42 archival retinoblastoma tumors and CA IX; a hypoxia marker in 33 tumors in the same cohort. The expression was correlated with tumor groups based on invasion, differentiation and IIRC. RESULTS: Expression of HIF-1α, survivin and CA IX was observed in 83% (35/42), 86% (36/42), and 93% (31/33) of tumors respectively. We observed no significance between HIF-1α and CA IX expression in tumors with invasion, differentiation and in IIRC tumor groups. An increased survivin expression was observed in group E tumors than in group D tumors (P = 0.044). A significant association was observed between HIF-1α and survivin in differentiated (r = -0.582; P = < 0.01) and undifferentiated tumors groups (r = 0.513; P = <0.012). A similar significant association was observed between HIF-1α and CA IX in tumors with high immunoreactivity for HIF-1α (r = 0.833; P = <0.01). CONCLUSION: Based on these observations, we propose that HIF-1α pathway is deregulated in RB. The role of drug resistance and the potential of targeting HIF-1α, CA IX, and survivin in RB should further examined.
Subject(s)
Antigens, Neoplasm/biosynthesis , Biomarkers, Tumor/biosynthesis , Carbonic Anhydrases/biosynthesis , Drug Resistance, Neoplasm , Gene Expression Regulation, Neoplastic , Hypoxia-Inducible Factor 1, alpha Subunit/biosynthesis , Inhibitor of Apoptosis Proteins/biosynthesis , Neoplasm Proteins/biosynthesis , Retinoblastoma/metabolism , Tumor Microenvironment , Antigens, Neoplasm/genetics , Carbonic Anhydrase IX , Carbonic Anhydrases/genetics , Cell Hypoxia , Child, Preschool , Female , Humans , Hypoxia-Inducible Factor 1, alpha Subunit/genetics , Inhibitor of Apoptosis Proteins/genetics , Male , Neoplasm Invasiveness , Neoplasm Proteins/genetics , Retinoblastoma/genetics , Retinoblastoma/pathology , Retinoblastoma/therapy , SurvivinABSTRACT
PURPOSE: To study the influence of serum-free B27 supplemented culture medium on corneal epithelial cells from limbal explants. METHODS: Human limbal tissues obtained from cadaveric donor eyes were used in this study. The morphological characteristics of cultivated epithelial cells were analyzed by phase contrast microscopy. Growth kinetics, bromodeoxyuridine (BrdU) labeling cell proliferation assay, and reverse transcriptase PCR (RT-PCR) for limbus and corneal markers were studied in serum-dependent and serum-free B27 supplemented corneal epithelial culture. The signaling pathway genes were analyzed by RT(2) qPCR profiler array. RESULTS: The corneal epithelial cells morphology and mRNA expression of markers were similar in both the serum-dependent and serum-free B27 supplemented culture. The growth and proliferation of the serum-free B27 supplemented culture was significantly higher than that of the serum-dependent culture. The wnt, hedgehog, survival, NFkB, Jak-Stat, and calcium protein kinase C pathways were highly expressed in the serum-free B27 supplemented corneal epithelial culture. CONCLUSIONS: Most signaling pathway genes are upfolded by B27 supplementation in the corneal epithelial cell culture; it could be an efficient replacement for serum.
