Differential MUC 1 expression in normal and neoplastic human pancreatic tissue. An immunohistochemical study of 60 samples

Neoplastic transformation of epithelial cell sis commonly associated with altered synthesis of mucin glycoproteins. Few studies have been performed on the correlation between MUC 1 expression and pancreatic carcinoma using immunohistochemical methods. We compared the patterns of MUC 1 expression in normal pancreatic tissue, in pancreatic carcinoma, and in chronic pancreatitis. Immunohistochemical studies were performed using 3 monoclonal anti-MUC 1 antibodies (12C10, 1G5, and H23) on surgical specimens and on fine-needle aspiration biopsy specimens. In the neoplastic cells from adenocarcinomas, high levels of cytoplasmic MUC 1 expression were observed, with some membrane staining. No such cytoplasmic expression was observed in normal tissue, tissue from chronic pancreatitis, or benign neoplastic tissue. These data show conspicuous quantitative and qualitative differences between the patterns of MUC 1 expression observed in nonmalignant vs malignant pancreatic tissue and may be useful in the histologic diagnosis of adenocarcinoma in biopsy samples.

Prognostic value of p53 protein expression in squamous cell carcinoma of the esophagus

In this study, we investigated endoscopic biopsy material consisting of 76 esophageal squamous cell carcinomas after immunostaining with three p53 monoclonal antibodies (PAb 1801, PAb 240, and DO-7). p53 protein was detected in 51.3% of the tumours. The protein was not expressed in the normal mucosa. Statistical analysis of follow-up data on 54 patients showed that high p53 levels were to a significant degree frequently associated with unfavorable treatment response (p < 0.053) and death (p < 0.05); whereas expression of the protein was not correlated with tumor differentiation, DNA ploidy, S phase value, EGF-R expression, or Ki67 index. The results of these studies suggest that in cases of esophageal carcinoma, immunohistochemical detection of p53 protein can be used to predict outcome.

Ultrastructural study of osteosarcomas

The ultrastructural examination of four osteosarcomas (osteogenic, undifferentiated, and pleomorphic) is described. There are three types of tumor cells. Most of the cells are held in contact by desmosome-like tight junctions; they are atypical osteoblasts with cytoplasmic processes, dilated rough endoplasmic reticulum, mitochondria carrying calcific inclusions, lipid droplets surrounded by glycogen, and intracellular fine filamentous fibers. Other cells exhibiting varying degrees of osteoblastic maturity are also seen with multilobed nuclei, a clear cytoplasm, and straight bordered membranes. The last type is chondroid with abundant deposits of glycogen, lipid droplets, and undilated rough endoplasmic reticulum. The matrix is composed of fibrils without periodicity, scattered and deteriorated collagen fibers, and focal calcium deposits of hydroxyapatite crystals as in embryonal bone, dentine, or callus bone.