RESUMO
PURPOSE: The actions of growth factors during healing of injured flexor tendons are not well characterized, although information pertinent to some individual growth factors is available. We studied gene expression and protein production of a number of growth factors at several time points during the early healing period in a chicken model. METHODS: Seventy-four long toes of 37 white Leghorn chickens were used. The flexor digitorum profundus tendons of 60 toes were surgically repaired after complete transection and were harvested for analysis 3, 5, 7, 9, 14, and 21 days after surgery. The expression of 6 growth factors was studied at 4 time points after surgery with real-time quantitative polymerase chain reactions, and production and distribution of 3 growth factors at all 6 time points were studied by immunohistochemical staining with antibodies. Fourteen tendons that had no surgery served as day 0 controls. Tendon healing status was also assessed histologically. RESULTS: Throughout the early tendon healing period, connective tissue growth factor (CTGF) and transforming growth factor beta (TGF-beta) showed high levels of gene expression. Levels of gene expression of vascular endothelial growth factor (VEGF) and insulin-like growth factor 1 (IGF-1) were high or moderately high. Expression of the TGF-beta gene was upregulated after injury, whereas the basic fibroblast growth factor (bFGF) gene was downregulated at all postsurgical time points and expressed at the lowest levels among 6 growth factor genes 2 to 3 weeks after surgery. The platelet-derived growth factor B (PDGF-B) gene was also minimally expressed. Findings of immunohistochemistry corresponded to TGF-beta, bFGF, and IGF-1 gene expression. CONCLUSIONS: In this model, up to 3 weeks after surgery, gene expression and production of TGF-beta are high and are upregulated in this healing period. However, expression of the bFGF gene and protein is low and decreases in the healing tendon. The CTGF, VEGF, and IGF-1 genes are expressed at high or moderately high levels, but PDGF-B is minimally expressed.
Assuntos
Traumatismos dos Tendões/genética , Traumatismos dos Tendões/metabolismo , Cicatrização/fisiologia , Animais , Galinhas , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Fator 2 de Crescimento de Fibroblastos/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Fator de Crescimento Insulin-Like I/genética , Fator de Crescimento Insulin-Like I/metabolismo , Proteínas Proto-Oncogênicas c-sis/genética , Proteínas Proto-Oncogênicas c-sis/metabolismo , RNA Mensageiro/metabolismo , Traumatismos dos Tendões/terapia , Fatores de Tempo , Dedos do Pé , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
BACKGROUND & OBJECTIVE: It is still unclear whether overexpression of mdr-1 gene play a role in the chemotherapy resistance of lymphoma. This study was designed to investigate P-glycoprotein(P-gp) and mdr-1 mRNA levels of lymphoma and to observed the impact of P-gp level upon chemotherapy response. METHODS: Ten samples of relapsed lymphoma and 21 samples of untreated lymphoma were assessed by flow cytometry(FCM). The mdr-1 mRNA levels were determined by real-time reverse-transcription PCR assay simultaneously in eighteen samples. The impact of P-gp levels upon chemotherapy response was observed in seventeen patients. RESULTS: Nineteen Percent (4/21) patients overexpressed P-gp at diagnosis as compared to 60%(6/10) in relapse(P = 0.012). The copy numbers of mdr-1 mRNA were 4 x 10(2)-1.32 x 10(4) copies/microgram RNA in untreated group and 4 x 10(2)-4 x 10(4) copies/microgram RNA in recurrent group. There existed significant difference in the distribution of mdr-1 mRNA expression between these two groups, P < 0.05. The complete response rates were 46% (6/13) in P-gp non-overexpression group and 25% (1/4) in P-gp overexpression group(P = 0.60). CONCLUSION: Relapsed lymphomas highly express P-gp and mdr-1 mRNA. The overexpression of mdr-1 gene may play a role in the multidrug resistance of relapsed lymphoma.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Linfoma/patologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/efeitos dos fármacos , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/uso terapêutico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Linfoma/genética , Linfoma/metabolismo , Recidiva Local de Neoplasia , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais CultivadasRESUMO
AIM:To study the telomerase expression in gastric carcinoma and its clinical implications.METHODS:Telomerase activity was examined in gastric cancer and corresponding normal tissues using a modified TRAP (telomeric repeat amplify-cation protocol) assay (TRAP-eze) in tissue samples from 94 gastric carcinomas and 58 normal tissues, 12 gastric adenomas and 9 gastric ulcer lesions.RESULTS:Telomerase activity was present in 81 of the 94 (86.2%) gastric cancer tissues, whereas no telomerase activity was detected in any normal tissues.The incidence of telomerase activity in gastric cancer tissues was unrelated to the tumor diameter, histological grade, tumor invasion in depth, lymph node metastasis and TNM stage.CONCLUSION:Telomerase plays an important role in carcinogenesis and progression of gastric cancer, and it is suggested to be a useful tumor marker.