A simple modification of the tetracycline bone labeling technique, based on the use of incident fluorescence, is introduced. The method has proven effective in the study of osteoneogenesis in bone grafts assisted by a soft tissue pedicle. The results obtained are highly specific, with new bone showing as a yellow band against blue background. The degree of fluorescence appears to be related to that of osteoneogenesis and correlates well with histological findings of the same specimens when examined by conventional light microscopy. The main advantages of this new technique over currently used methods are 1) avoidance of the time-consuming thinning procedure; 2) ability to study bone and surrounding soft tissue simultaneously; and 3) one-to-one comparison and documentation of the results of fluorescence and histological examination of the same specimen.

Animals↗

PubMedDate not supplied

Transforming growth factor alpha (TGF-alpha) expression in biopsies of colorectal carcinoma is a significant prognostic indicator.

BACKGROUND: Predicting the outcome of patients with colorectal adenocarcinoma (CRCA) prior to surgery would be valuable in selecting high-risk individuals who may benefit from pre-operative adjuvant therapy. The aim of this study is to determine whether the expression of TGF-alpha in preoperative biopsies of patients with CRCA constitutes a significant prognostic indicator. METHODS: We studied the expression of TGF-alpha in preoperative biopsies of 106 patients with CRCA, who had at least 5 years follow-up, using an anti-TGF-alpha monoclonal antibody and utilizing the ABC immunoperoxidase technique. For survival analysis, we used the actuarial survival method, and the Log Rank test for statistical significance. RESULTS: CRCAs with low TGF-alpha expression (less than 25% of the tumor cells immunoreactive for TGF-alpha) had a significantly poorer survival than those with high TGF-alpha expression (more than 25%). After excluding from analysis biopsies showing mucinous or poorly differentiated CRCA, known predictors of poor prognosis, the results remained significant (p = 0.0289). CONCLUSION: It is concluded, therefore, that low or absent expression of TGF-alpha in pre-operative biopsies of patients with CRCA, as detected by immunohistochemistry, is a significant predictor of an unfavorable outcome.

Actuarial Analysis↗

PubMedDate not supplied

Immunohistochemical detection of Glut3 in human tumors and normal tissues.

Malignant cells have been shown to utilize more glucose than normal cells in vitro and in vivo. Glut3 is a member of the facilitative glucose transporters family of transmembrane proteins, and its mRNA levels has been found to be elevated in human cancers, indicating that it may play a role in glucose uptake by cancer cells. Localization and extent of expression of Glut3 protein in normal and malignant human tissues is still largely unknown. We studied Glut3 expression in a series of 325 benign and malignant human tissues using standard immunoperoxidase technique. Of the normal tissues tested, Glut3 immunoreactivity was detected only in normal testis and placenta. Twelve of 14 (86%) testicular, 3 of 22 (16%) ovarian, 2 of 8 (25%) gastric, and 11 of 41 (27%) non-small cell lung carcinomas were positive for Glut3. Other carcinomas, including those of the breast and colon, were negative. Only in Glut3-positive testicular carcinomas were most tumor cells Glut3-positive. We conclude that a) Glut3 has a limited expression in normal and malignant human tissues, as determined by immunohistochemical staining, b) Glut3 may play a role in glucose uptake in a subset of carcinomas of the lung stomach and ovary, and, therefore, these tumors may have a distinct clinical behavior, and c) Glut3 may be an attractive target for monoclonal therapy or imaging of testicular germ cell tumors.

Blotting, Western↗