RESUMO
Several studies have reported that proliferating cell nuclear antigen (PCNA), nucleolar organizer regions (NOR) and epidermal growth factor receptor (EGF-R) are cellular proliferation parameters in malignant tumours. However, the correlation of EGF-R with PCNA and NOR has not been reported in colon tumours. To clarify this, we investigated the correlation of the expression of EGF-R with PCNA and NOR in colonic epithelial tumours. Using immunohistochemical staining and one-step silver staining techniques, the expressions of EGF-R-, PCNA- and NOR-associated protein were studied in paraffin sections from five normal mucosae, 10 adenomas with mild atypia, 16 adenomas with moderate atypia, 32 adenomas with severe atypia including carcinoma in situ and 47 with invasive colon carcinomas. Significant differences were found among the respective degrees of atypia in Ag-NOR counts, PCNA labelling index (LI), and the expression of EGF-R. However, there were no significant differences among the Ag-NOR counts of the severe atypia and invasive carcinoma. There was a significant positive correlation between Ag-NOR counts and PCNA LI (P < 0.001). The Ag-NOR counts and PCNA LI in EGF-R-positive cases were higher than in EGF-R-negative cases (P < 0.001). These results indicate that each of the parameters increased significantly with the increase in atypia and the progression of cancer. Epidermal growth factor receptor provokes an exacerbation of protein synthesis and the cell cycle in colonic epithelial tumours.
Assuntos
Neoplasias do Colo/patologia , Receptores ErbB/metabolismo , Região Organizadora do Nucléolo , Antígeno Nuclear de Célula em Proliferação/metabolismo , Adenoma/metabolismo , Adenoma/patologia , Adenoma/ultraestrutura , Carcinoma/metabolismo , Carcinoma/patologia , Carcinoma/ultraestrutura , Divisão Celular , Neoplasias do Colo/metabolismo , Neoplasias do Colo/ultraestrutura , Humanos , Imuno-Histoquímica , PrognósticoRESUMO
p16 (MTS-1, multiple tumor suppressor gene 1), a putative tumor suppressor gene, is one of the cyclin-dependent kinase inhibitors (CDI) and it regulates the G1/S transition of the cell cycle. To clarify the role of p16 in primary gastric cancer, we have investigated somatic mutations of this gene by using the polymerase chain reaction/single strand conformation polymorphism (PCR-SSCP) method. In 23 surgical specimens of primary gastric cancer, none were detected in exon1 and exon 2. Among the 6 human gastric cancer cell lines examined, PCR products were not found in 2, MKN28 and MKN45, suggesting the presence of homozygous deletions. No mutation was found in the other 4 cell lines. Furthermore, decreased expression levels were not observed in 13 gastric cancer tissues by reverse transcription PCR (RT-PCR). Considering the above results of PCR-SSCP and RT-PCR, genetic alterations of the p16 gene are rarely implicated in human gastric cancer tumorigenesis.
Assuntos
Proteínas de Transporte/análise , Genes Supressores de Tumor , Inibidores de Proteínas Quinases , Neoplasias Gástricas/genética , Actinas/análise , Linhagem Celular , Inibidor p16 de Quinase Dependente de Ciclina , Humanos , Reação em Cadeia da Polimerase , Estômago/química , Neoplasias Gástricas/química , Células Tumorais CultivadasRESUMO
Treatment of severe microstomia caused by swallowing of caustic soda is presented. The oral cavity was severely constricted because of mucosal adhesions. We used a free forearm flap for reconstruction of the oral cavity and vermilion flaps at the oral commissure, with satisfactory results. A technique is presented, and the problems with respect to the reconstruction of the oral cavity are discussed.
