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Objective: Malignant cells exhibit increased glucose uptake and utilization in vitro and in vivo. This process is thought to be mediated by the glucose transporter (Glut) family. The aim of this study was to elucidate the clinical significance of Glut1 expression at the site of deepest invasion as a predictor of the invasive/metastatic potential and prognosis of advanced colorectal carcinoma (CRC). Methods: One hundred and fifty-two patients who had undergone surgical resection for advanced CRC were entered in this study. Histologic subclassifications at the deepest invasive site included well-differentiated (W), moderately to well-differentiated (Mw), moderately to poorly differentiated (Mp), poorly differentiated (Por) and mucinous (Muc) adenocarcinomas. Glut1 expression was examined immunohistochemically with a labeled streptavidin-biotin kit using anti-Glut1 polyclonal antibody MYM. As a marker of cell proliferation, Ki-67 expression was also examined. All immunoreactivity was analyzed at the deepest invasive site, central portion and superficial part. The immunohistochemical expression of Glut1 was defined as positive if distinct staining of the membrane or cytoplasm was observed in at least 30% of tumor cells. Results: Glut1 expression was detected in 56 of 152 lesions (36.8%) at the deepest invasive site. The incidence of Glut1 expression at the deepest invasive site correlated significantly with histologic grade (W/Mw grade, 28% vs. Mp/Por/Muc grade, 48%), depth of invasion (invasion of muscularis propria/invasion of subserosa or subadventitia, 29% vs. invasion of serosa or adventitia/invasion of adjacent structures, 52%), lymphatic invasion (absence of lymphatic invasion, 19% vs. presence of lymphatic invasion, 40%), lymph node metastasis (absence of lymph node metastasis, 25% vs. presence of lymph node metastasis, 41%) and Duke’s stage (Duke’s

Purpose: Tissue growth depends on both cell proliferation and cell death. This study was designed to examine the growth characteristics of rectal carcinoid tumors. Methods: Fifty rectal carcinoid tumors were studied clinicopathologically and experimentally. Expression of Ki-67, TGF-α, p53, and bcl-2 was examined immunohistochemically, and apoptotic cells were identified by the in situ DNA nick end labeling method. EGF receptor expression was examined by a colorimetric in situ mRNA hybridization technique. Results: The median Ki-67 labeling index (LI) in all lesions was 0.62 ± 0.59%. Ki-67 LI was significantly (p < 0.01) higher in lesions larger than 5 mm than in lesions smaller than 5 mm. TGF-α was expressed more frequently (p < 0.01) in lesions larger than 5 mm (100%) than in lesions smaller than 5 mm (65.2%). Ki-67 LI was significantly (p < 0.05) higher in lesions with TGF-α expression than in lesions without TGF-α expression. The in situ hybridization revealed EGF receptor expression in all 46 lesions with intact mRNA (100%), and coexpression of TGF-α and EGF receptor was found in 39 of the 46 (84.8%) lesions. The median apoptotic index (AI) in all lesions was 0.15 ± 0.12%. AI has increased with tumor size and was significantly (p < 0.05) higher in lesions with a higher Ki-67 LI than in lesions with a lower Ki-67 LI. p53 protein was detected in only 1 patient who had liver metastases, and the gene mutation was confirmed by polymerase chain reaction and single-strand conformation polymorphism analysis. bcl-2 expression was absent in all lesions. Conclusions: The Ki-67 LI indicated a low cellular proliferative activity in rectal carcinoid tumors. AI was very low, and was significantly correlated with proliferative rate. Inhibition of apoptosis by mutated p53 or bcl-2 may not have occurred in most of these tumors. TGF-α/EGF receptor autocrine mechanisms may play a possible role in tumor growth, and the cellular proliferative activity may increase as tumors grow larger.Copyright © 2000 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Purpose: The mucin core peptide MUC1 often is detectable in colorectal carcinoma (CRC) tissue and cell lines. However, whether MUC1 in CRC correlates with tumor histogenesis and progression is unclear. We studied the relationship between MUC1 expression in intramucosal CRC and clinicopathologic features, expression of Ki-67, and p53 protein, and apoptosis. Methods: The intramucosal CRC we studied included 140 endoscopically or surgically resected lesions, including 106 low-grade carcinomas and 34 high-grade carcinomas. De novo carcinoma, defined as carcinoma with no adenomatous component, represented 9 of 140 tumors. Three macroscopic types were identified: 57 lesions were polypoid, 55 were superficial and flat, and 28 were granular-type laterally spreading tumors (G-LST). MUC1, Ki-67, and p53 expression were examined immunohistochemically. Apoptotic cells were identified by in situ DNA nick end labeling. Results: MUC1 expression in high-grade carcinomas was significantly more frequent (p < 0.01) than in low-grade carcinomas; expression in adenomas was almost nil. MUC1 expression in polypoid carcinomas was significantly more frequent (p < 0.05) than in superficial carcinomas or G-LST. MUC1 expression in carcinomas with p53 expression was significantly more frequent (p < 0.01) than in carcinomas not expressing p53. No significant correlation was found between expression of MUC1 and Ki-67 labeling index. MUC1 was expressed more frequently in carcinomas with relatively high apoptotic index (p < 0.01). MUC1 expression did not differ between de novo carcinomas and those developing from adenomas. Conclusions: The results suggest that MUC1 is likely to be expressed in the course of colorectal carcinoma development when p53 protein is overexpressed and apoptosis is prominent. [ABSTRACT FROM AUTHOR]

This study sought to examine the relationship between MUC1 expression at the deepest invasive portion, invasive/metastatic potential, and prognosis of colorectal cancer in relation to cellular proliferation. MUC1 expression was detected immunohistochemically using KL-6 antibody (anti-MUC1 monoclonal antibody) in 100 surgically resected specimens of advanced colorectal cancer. Distinct staining of the luminal surfaces, defined as positive immunoreactive (IR)-MUC1 expression, was seen in more than 30% of the tumor cells at the deepest invasive portion. The proliferating cell nuclear antigen labeling index (PCNA-LI) was also examined in the same areas. IR-MUC1 expression was detected in 71 (71%) of 100 lesions. Lesions with lymphatic or venous invasion showed a significantly higher incidence of IR-MUC1 expression than those without lymphatic or venous invasion (80 vs. 42% and 82 vs. 61%, respectively). Lesions with lymph node metastasis showed a significantly higher incidence of IR-MUC1 expression than those without lymph node metastasis (88 vs. 53%). Lesions with liver metastasis showed a significantly higher incidence of IR-MUC1 expression than those without liver metastasis (92 vs. 59%). Dukes’ stage was also significantly correlated with IR-MUC1 expression. The incidence of IR-MUC1 expression did not significantly differ with regard to histologic subclassification and depth of invasion. There was no significant correlation between IR-MUC1 expression and the PCNA-LI. IR-MUC1 expression at the deepest invasive portion revealed a significant correlation with prognosis; furthermore, in patients with better differentiated lesions, in those with lesions confined to muscularis propria or subserosa (subadventitial) invasion, in those with Dukes’ B and C, or in those undergoing curative resection, IR-MUC1 expression significantly correlated with prognosis. Patients with high PCNA-LI lesions showed a significantly poorer prognosis than those with low PCNA-LI lesions. Only in patients undergoing curative resection, patients with IR-MUC1-positive and high PCNA-LI lesions showed a significantly poorer prognosis than those with IR-MUC1-negative and low PCNA-LI lesions. The significant risk factors in the order of poorer prognosis in patients undergoing curative resection by the multivariate analysis were the histologic grade (moderately–poorly, poorly or mucinous adenocarcinomas), IR-MUC1 expression, and lymph node metastasis. These results indicate that IR-MUC1 expression is an important predictor of the metastatic potential and the prognosis of colorectal cancer, independent of histologic grade, depth of invasion or cellular proliferative activity. Combined analysis of IR-MUC1 and histologic grade, and combined expression of IR-MUC1 and PCNA at the deepest invasive portion are especially useful in predicting colorectal cancer prognosis. [ABSTRACT FROM AUTHOR]

HLA-DR antigen expression and the proliferating cell nuclear antigen labeling index (PCNA-LI) were examined immmunohistochemically in 59 surgically resected advanced colorectal cancers to clarify the clinicopathologic significance of the HLA-DR antigen. HLA-DR antigen expression was detected in 33 (56%) of the 59 lesions, which showed less frequent liver metastasis than lesions without HLA-DR antigen expression (40 vs. 68%; p < 0.05). Five-year survival rates of patients with and without HLA-DR antigen expression were 50 and 19%, respectively. Lesions combining HLA-DR antigen expression and a relatively low PCNA-LI had the best prognosis. These results indicate that HLA-DR antigen expression, particularly combined with a low PCNA-LI, is an important outcome predictor in colorectal cancer. [ABSTRACT FROM AUTHOR]