Loss of PTEN expression has been associated with advanced stages of tumor. Tumor angiogenesis is involved in tumor progression. In breast cancer, a high frequency of mutations of the PTEN locus has been reported. However, the prognostic importance of PTEN expression and its correlation with angiogenesis in breast cancer have not been well established. Formalin-fixed, paraffin-embedded tissues from 99 women with a primary diagnosis of invasive ductal carcinoma were evaluated for PTEN expression by immunohistochemical methods. The microvessel density (MVD) was also studied by immunohistochemical labeling of endothelial cells with CD34 antibody. Computerized image analysis was used to evaluate MVD. Reduced PTEN expression was seen in 27.3% of invasive ductal carcinoma. The MVD ranged from 22.0 to 197.0, with a median value of 58.5 (65.4 +/- 27.9). Reduced PTEN expression correlated with lymph node status (P < 0.01), tumor grade (P < 0.05), and tumor-node-metastasis (TNM) stage (P < 0.05). There was a statistically significant correlation between reduced PTEN expression and increased MVD (P < 0.05). The mean MVD was higher in reduced PTEN-expressive tumors, irrespective of stage, compared with normal PTEN-expressive tumors with the same stage. On multivariate analysis, only TNM stage and reduced PTEN expression correlated with survival. Our results suggest that reduced PTEN expression may be an independent prognostic indicator in patients with invasive ductal carcinoma. PTEN loss may be associated with increased tumor angiogenesis.
Our data do not show a direct regulation of VEGF expression by p53. We suggest that VEGF expression plays a role in the promotion of angiogenesis in RCC.
Recent molecular studies indicate two different genetic pathways leading to the development of glioblastoma; final progression of astrocytoma and de novo formation. To define the mutual relationships of cytogenetic changes in the pathogenesis of glioblastoma, molecular histopathologic alterations of p53 and epidermal growth factor receptor (EGFR) were evaluated by single stranded conformational polymorphion, reverse transcriptase-polymerase chain reaction and immunohistochemical stains in 15 primary and 21 secondary glioblastomas. Mutations in p53 gene and positive immunoreactivity to p53 protein (DO1) were more prevalent in secondary glioblastomas than in primary glioblastomas. A correlation between p53 mutations and p53 immunopositivities in glioblastomas was observed in 83.3% of the cases. All cases with positive p53 immunoreactivities showed p53 mutations; however, 13.9% of glioblastomas with p53 immuno-positivities lacked the relevant mutations. EGFR amplifications were detected in 73.3% of primary glioblastomas and 9.5% of secondary glioblastomas (p<0.001). The concurrence of p53 mutation and EGFR amplification was revealed in only 2 out of 15 primary glioblastomas and none among the secondary glioblastomas. Immunoreactivities for EGFR were noted in 66.7% of primary glioblastomas and in 9.5% of secondary glioblastomas (p<0.001). A correlation between EGFR amplification and EGFR immunopositivity in glioblastomas was observed in 91.7% of the cases. These data indicate that EGFR amplification and p53 mutations are two independent genetic events in the development of glioblastomas.
Most colonic multiple mucosa-associated lymphoid tissue (MALT) lymphomas are confirmed with a histologic and immunohistochemical staining of the mucosal biopsy specimen obtained during colonoscopic examinations. Endoscopically, colonic MALT lymphomas frequently appear as protruding and/or ulcerative lesions, and there are not so many reports of colonic MALT lymphoma as compared to the frequent reports of MALT lymphoma of stomach. We report a unique case of colonic MALT lymphoma presenting as a simple reddish discoloration of mucosa; this presentation has never been describe before. Our patient was a 47-yr-old male who suffered from tenesmus and mucoid stool. A colonoscopy was accomplished, followed by a histologic examination and we diagnosed a colonic MALT lymphoma. Staging of the disease was done because this was necessary for choosing the modality of treatments. The patient was then treated with polychemotherapy in conjunction with radiation therapy.
Adenomyoma of the small intestine is an extremely rare entity characterized by a mixture of glandular structures lined by columnar epithelium, with intervening bundles of smooth muscle. We report a case of adenomyoma of the jejunum that caused intussusception in an adult. Histologically, the morphologic features are typical of adenomyoma and are noteworthy for the extensive cystic change.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.