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To study, under controlled conditions, the applicability of automated image analysis of immunohistochemical markers as an indicator of development and progression in tobacco component-induced tumors in the respiratory tract.Amount, location, size, shape and intensity of staining of proliferating cell and p53 antigen in chemically induced precursors and squamous cell carcinoma of the hamster lung were determined by computer-assisted morphometry.The total expression of proliferating cell nuclear antigen (PCNA) and p53 expression increased consistently during the formation of papillomas and squamous cell carcinomas of the larynx, trachea, bronchi and lungs. Individual preneoplastic cells in epithelial dysplasia expressed PCNA staining, increasing with increasing cell size and optical density, indicating antibody- staining intensity, in relation to the increased degree of cellular atypia. In malignant tumors, cell size decreased with decreasing differentiation, while antibody staining intensity remained unchanged. The increased alterations in cell shape and percent PCNA-positive cells observed in dysplastic epithelium and squamous cell carcinomas were statistically significant using Spearman's correlation coefficient. Squamous cell carcinomas consisted of two tumor cell populations with different cell shapes, and PCNA and p53 staining intensity. Altering measurement conditions-antibody threshold levels, size of measured area and repeating measurements-showed computer-assisted image analysis to give sensitive, reliable and consistent results.Computer-assisted analysis of immunohistochemical staining showed high sensitivity and reproducibility; however, the results depended upon the method of study.

Malignant ovarian tumors induce a strong fibro-proliferative reaction characterized by the active production of type I and type III procollagen both locally in the ovary as well as more remotely in the peritoneal cavity. Our purpose was to determine the origin of the increased collagen production observed in serous ovarian tumors with different histological grades of malignancy, ie, whether the malignant cells or the stromal fibroblasts are responsible for the synthesis of collagen fibers. We visualized the mRNAs corresponding to the pro alpha 1(I) and pro alpha 2(I) chains of type I procollagen and the pro alpha 1(III) chain of type III procollagen by in situ hybridization. Strong signals for both chains of type I procollagen were seen in stromal fibroblasts next to tumor cell islets, whereas the reaction was weak or absent near benign ovarian cysts. In poorly differentiated tumors, the signals were particularly abundant and occasionally also seen in the neoplastic cells themselves. Type III procollagen mRNA expression was similar, although somewhat less distinct. These findings indicate that the production of interstitial procollagens is related to the degree of malignancy and neoplastic activity of tumors. The formation of collagen in well differentiated ovarian tumors is a function of stromal fibroblasts, whereas in poorly differentiated tumors, aberrant expression of one or several chains of type I and type III procollagens in the neoplastic cells is also likely to take place.

Immunoreactivity for syndecan, a cell surface proteoglycan, which binds extracellular matrix molecules and growth factors, was studied in hairless (hr/hr) mice exposed to UV-A and UV-B irradiation. Positive staining was observed at the surface of normal epidermal cells as well as in the dermal abortive hair follicle cysts characteristic to this mouse strain. Early reaction to UV-irradiation showing hyperplastic epidermis with slight cellular atypia showed also positive, although reduced, staining of epidermal cell surfaces. Specimens with severe dysplasia showed weak staining in the granular cell layer, whereas the basal cell layer was negative. In papillomas and keratoacanthomas, immunoreactivity for syndecan was observed in the benign hyperplastic epidermal cells as well as in the proliferating epidermal cells of the horn cysts. Malignant transformation of epithelium, expressed as the formation of early invasive and anaplastic squamous cell carcinomas, was uniformly associated with loss of syndecan staining. These results are consistent with the previous findings of reduced expression of syndecan associated with malignant transformation of cultured epithelial cells, but also suggest an important role for syndecan in the maintenance of normal tissue architecture and differentiation pattern of the skin.

The occurrence and intensity of staining for specific antibodies against the aminoterminal propeptide of type 111 procollagen (PIIIP), which is indicative of the synthesis and the degradation of that collagen type, was studied in sections from normal and alcoholic livers and compared with serum PIIIP levels, serum antipyrine clearance, fibronectin distribution and morphology as revealed by conventional stains and electronmicroscopy. Positive staining for PIIIP and fibronectin was observed in the perisinusoidal space of the normal liver and in portal tracts. In alcohol-induced fatty liver positive staining increased around the central veins, in alcoholic hepatitis increased staining reaction was seen to a limited extent in areas of cell injury. Extensive reticulin and PIIIP-positive areas were found in the periportal interstitium of the cirrhotic livers and in large fibrotic areas extending into the surrounding parenchyma in cases of active disease. The results show a distinct relationship between collagen type 111 metabolism, morphologically detectable hepatic injury and liver cell function tests, with tissue deposition occurring later in the disease process than biochemically detectable serum collagen levels and signs of altered liver cell function.

The addition of phenobarbital (PB) to a sulphonylurea (SU) regimen may improve glycemic control in patients with non- insulin dependent diabetes mellitus (NIDDM, type II). Since SU reactions may be modified, we investigated glucose metabolism in rats with combined PB and SU treatment. Chlorpropamide (CHL) and glibenclamide (GB) were selected as SU drugs. The combination of PB to the CHL or GB regimens induced the drug metabolism enzymes excluding aminopyrine N-demethylase activity, which was enhanced by GB but not CHL. The CHL and GB treatments lowered blood glucose (BG) concentration and decreased hepatic glucose-6-phosphate phosphohydrolase (G6P hydrolase) activity and glycogen reserves in the rats. The concomitant administration of PB and the SUs decreased hepatic G6P hydrolase activity and glycogen content in the animals, whereas the BG level remained unaltered. The hepatic glycogen content was decreased more markedly in the CHL plus PB than in the CHL alone treated animals. The findings suggests that enzyme inducers modify the action of SU in rats. Hepatic drug and glucose metabolizing enzymes seems also to respond to distinct PB plus SU combinations in different ways.