RESUMEN
PURPOSE: The prognostic factors of chondrosarcoma remain uncertain as only a few large studies with long-term follow-up have been reported. The aim of this study was to analyze oncological outcomes and prognostic factors. MATERIALS AND METHODS: A retrospective review of oncological outcomes and prognostic factors was performed on 125 consecutive chondrosarcoma patients who underwent surgery at our institution. RESULTS: Overall survival was 91.6%+/-2.5%, 84.1%+/-3.8%, and 84.1%+/-3.8% at 5, 10, and 15 years respectively. Among the histological types, dedifferentiated type showed the worst survival (p < 0.001). As for conventional type chondrosarcoma, histologic grade and anatomical location predicted outcome, with high-grade with axial location having the worst outcome (p < 0.001). In contrast, low-grade chondrosarcoma of appendicular skeleton could be treated safely by intralesional curettage. CONCLUSION: Histological type was significantly associated with the outcome of chondrosarcoma. For the conventional type, histologic grade and anatomical location predicted outcome, with high-grade with axial location having the worst outcome.
Asunto(s)
Humanos , Condrosarcoma , Legrado , Estudios de Seguimiento , Pelvis , Pronóstico , Recurrencia , Estudios Retrospectivos , EsqueletoRESUMEN
SV40 large T antigen, a viral oncoprotein, is known to immortalize human diploid fibroblast by soaking up cellular RB and p53, but its frequency is extremely low. Additional genetic alteration is necessary for single-step immortalization. We attempted to find out what this alteration is by overexpressing cellular signal mediator genes; c-myc and cyclin D frequently amplified in many cancer cells. Overexpression of cyclin D did not affect the immortalization, but, overexpression of c-myc along with T antigen could immortalize normal human diploid fibroblast. Several cellular markers tested during immortalization process showed that p21, a cyclin-dependent kinase inhibitor and a marker of cellular senescence, disappeared in the life span-extended cells by T antigen and in the immortalized cells by c-myc. p21 was, however, elevated in the senescent cells and in the cells of crisis. Interestingly, p16 was upregulated whenever T antigen is overexpressed. Telomerase activity was also activated only in the immortalized cells. These results suggest that overexpression of c-myc contributes to immortalization of human diploid fibroblast by activating telomerase activity and suppressing p21 activity.
Asunto(s)
Humanos , Antígenos Transformadores de Poliomavirus/genética , Biomarcadores , Senescencia Celular/genética , Transformación Celular Viral , Células Cultivadas , Ciclinas/metabolismo , Diploidia , Fibroblastos/metabolismo , Genes myc/genética , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Virus 40 de los Simios/genética , Telomerasa/metabolismoRESUMEN
SV40 large T antigen, a viral oncoprotein, is known to immortalize human diploid fibroblast by soaking up cellular RB and p53, but its frequency is extremely low. Additional genetic alteration is necessary for single-step immortalization. We attempted to find out what this alteration is by overexpressing cellular signal mediator genes; c-myc and cyclin D frequently amplified in many cancer cells. Overexpression of cyclin D did not affect the immortalization, but, overexpression of c-myc along with T antigen could immortalize normal human diploid fibroblast. Several cellular markers tested during immortalization process showed that p21, a cyclin-dependent kinase inhibitor and a marker of cellular senescence, disappeared in the life span-extended cells by T antigen and in the immortalized cells by c-myc. p21 was, however, elevated in the senescent cells and in the cells of crisis. Interestingly, p16 was upregulated whenever T antigen is overexpressed. Telomerase activity was also activated only in the immortalized cells. These results suggest that overexpression of c-myc contributes to immortalization of human diploid fibroblast by activating telomerase activity and suppressing p21 activity.