Polygonal Epithelial Cells Research Articles

Primary cultured cells and an established cell line of human hepatocellular carcinomas.

Cancer cells obtained from human hepatocellular carcinoma nodules were subjected to primary culture, and a hepatoma cell line was established. The cell clumps obtained by needle puncture were plated directly in plastic tissue culture flasks without any cell dissociation procedures. Cell clusters became attached to flasks in 24 h with an efficiency of about 90%. No fibroblast outgrowth was observed. Primary cultured cells were composed of polygonally shaped epithelial cells with dense cytoplasm and one or more large nuclei. They excreted plasma protein biosynthetic markers of hepatocytes into the culture medium. Plasma protein synthesis of primary cultured hepatoma cells decreased as the age of the primary cultures increased. Cells seeded in September 1980 started to grow continuously after 5 months of cultivation. A new hepatocellular carcinoma cell line (designated as KG55T) was established from these growing cells. KG55T cells have been subcultured for more than 20 passages and form a monolayer of polygonal epithelial cells which pile up after they reach confluence. The cells had a doubling time of 50-60 h and a plating efficiency of 60-65%. Albumin, alpha 1-antitrypsin and alpha 2-macroglobulin syntheses and tyrosine aminotransferase activity were detected. At the 10th passage, KG55T cells were pseudotriploid (mode, 69), and 8q+ and 15q+ translocations were distinctive of this cell line. The morphological characteristics and the capacity for plasma protein synthesis of the primary cultured hepatoma cells and cells of the established hepatoma cell line were compared.

A × C Rat Prostate Adenocarcinoma: Initial Characterization of Testosterone Regulation of Hormone Receptors of Cultured Cancer Cells and Derived Tumors<xref ref-type="fn" rid="FN2">2</xref><xref ref-type="fn" rid="FN3">3</xref>

A x C rat prostate cancer cells were established in continuous culture. The polygonal epithelial cells had granular cytoplasm and well-defined cell margins, contained round to oval nuclei with prominent nucleoli, and were tumorigenic when inoculated into A x C male rats. The tumors produced by the injected prostate cancer cells grew as well-vascularized, solid, cribriform adenocarcinomas. The rat prostate cancer cells and derived tumors contained cytoplasmic and nuclear androgen receptors and prolactin receptors. Androgen regulation of prolactin receptor content and androgen receptor distribution in A x C rat prostate cancer cells were comparable to those of the normal ventral prostate gland. These studies suggest that the A x C rat prostate cancer cells and tumors may represent a unique model for studies of hormonal regulation of prostate cancer cell behavior.

Tissue culture of benign and malignant human prostatic tumors. I. Morphological observation on cultured cells (author's transl)

Prostatic tissues from 34 patients who were suspected to suffer from prostatic cancer were obtained by either rectal or perineal needle biopsy. The tissues were minced into small explants and were placed in T-D 15 flasks and were immersed in a culture medium consisting of Eagle's MEM supplemented with 10% calf serum or bovine serum and were placed in an incubator at 37°C. Outgrowth of monolayer cells was observed morphologically by means of an inverted phase-contrast microscope and photographed. Some tissues were fixed and stained for histopathological observation.Histopathological diagnosises of 34 cases were benign prostatic hypertrophy in 14 cases prostatic adenocarcinoma in 16 cases, suspected carcinoma in 2 cases, reticulum cell sarcoma in 1 case and chronic prostatitis in 1 case.As the results of tissue culture, 4 cases of benign hypertrophy, 11 cases of prostatic adenocarcinoma and 1 case of reticulum cell sarcoma formed monolayer cell sheet over 2 weeks. Therefore, the successful rate was statistically higher in prostatic carcinoma (68.8%) than in hypertrophy (28.6%).In phase contrast microscopy, both the polygonal epithelial cells and the spindle-shaped fibroblastic cells were observed in all the cases of benign prostatic hypertrophy. On the contrary, epithelial cells were dominant in 6 cases of prostatic adenocarcinoma while both the epithelial and the fibroblastic cells were equivalent in other 5 cases of adenocarcinoma. The rate of appearance of the epithelial cells tended to be higher in the adenocarcinoma than in the hypertrophy. All cells in reticulum cell sarcoma were epithelial cells.Although no established cell line was obtained due to infection, many cell strains were obtained from both the biopsied tissues of benign prostatic hypertrophy and prostatic adenocarcinoma, which were maintained in vitro for more than 2 weeks. These cell strains can be used as the experimental models to study the effects of sex hormones upon the prostatic cells.

Long-term cell culture of adult rat liver epithelial cells

The livers of adult rats were dissociated after collagenase-hyaluronidase perfusion. A high yield of viable cells was obtained and these regularly gave rise to continuous lines of polygonal epithelial cell types.

Some morphological observations of Reissner's membrane.

Light microscopic photographs of the dissected Reissner's membrane of an albino guinea pig were shown. Polygonal flat epithelial cells on the side of the scala media are larger on the outer side of the membrane than on the inner side of it. Bet-ween the outer and the inner sides of this membrane a transitional zone was noticed. Viewed from the inner side of the membrane, this zone—covering the area from the base to the apex—is nearer the base than the apex. It may be assumed that the outer larger cells are more active in their function than the inner smaller cells. There might also be reason to assume that the epithelial cells of Reissner's membrane grow larger as they move from the inner to the outer side of it.

The stereo ultrastructure of the external and internal surface of the cornea

The surfaces of the epithelium and the endothelium of the cornea were studied with the Stereoscan and with the conventional electron microscope. The polygonal (mostly hexagonal) epithelial cells of the outermost layer display straight cell borders and closely arranged, partly parallelized microvilli and microplicae. The limiting unit membrane on the surface of these epithelial cells has a special osmiophilic outer layer 60–90 Å thick. Scale-like lipid particles seem to come off from this layer. The endothelium is markedly different from the epithelium. Whereas it also consists of hexagonal cells, these interlock digitately on the margin toward the anterior chamber by means of very flat, long processes. This margin displays slender, solitary, widely scattered microvilli. The endothelial cells communicate with each other by desmosomes and attachment zones type I (Sjöstrand), whereas the epithelial cells are linked by desmosomes only.