Estrogen binding component in the pilosebaceous tumor developed in Suncus murinus.

We transplanted a pilosebaceous tumor developed on the sidegland of Suncus murinus to male nude athymic (BALB/c-nu/nu) mice. This tumor can be transplanted to female hosts as well, with a lower rate of graft-taking and slower growth rate. In this study we demonstrated the presence of macromolecules which specifically bind to estrogen. Measurement of 17 beta-estradiol (E2) binding by a dextran-coated charcoal assay revealed that the number of binding sites and the dissociation constant were 22.3 +/- 4.6 fmol/mg protein and 1.4 +/- 0.24 X 10(-9) M, respectively. This binding was specific for E2 and diethylstilbestrol (DES). Sucrose gradient centrifugation of the [3H]E2-labeled cytosol yielded a sharp peak of radioactivity at 3.5S-4S under high salt conditions and a 9S peak with a shoulder at 3.5S under low salt conditions. This 3.5S shoulder was due to dissociation of [3H]E2 from the 9S peak during the centrifugation, since only the 9S peak was obtained by postlabeled density gradient analysis. An assay of the in vivo binding of [3H]E2 showed significant radioactivity in the nuclear extract from the tumor. This nuclear uptake was markedly decreased by simultaneous administration of 100-fold excess of E2. In tumor-bearing castrated nude mice, 1-100 micrograms/day of E2 did not affect tumor growth, whereas it counteracted the stimulative effect of testosterone propionate.

Sebaceous lymphadenoma: ultrastructural observations and lipid analysis.

Sebaceous lymphadenoma is a rare, benign neoplasm of the parotid gland. In the 18 years since the initial report seven additional cases have been published. None includes ultrastructural studies or lipid analysis. Electron microscopy shows that the epithelial cells undergo a progressive maturation from basal to the typical lipid-laden mature sebaceous cells as in the cutaneous sebaceous glands. No morphologic differences are found between cutaneous sebaceous glands and the sebaceous glands in this parotid neoplasm. Thin-layer chromatography demonstrates the same type of lipids in the subaceous lymphadenoma as well as in cutaneous sebaceous glands. These findings suggest that the parotid salivary gland may be ectodermally rather than endodermally derived.

Lipid droplet of sebaceous carcinoma. Electron microscopic study utilizing glycol methacrylate-glutaraldehyde-urea procedure.

The ultrastructure of lipid droplets of sebaceous carcinoma (Meibomian gland carcinoma) was studied by conventional methods and a lipid-retention procedure. Two different structures were clearly differentiated by the latter technique. The peripheral part of the lipid droplet was composed of whirled lamellar structures (myelin-like structures) while the interior appeared to be continuously homogenous. The lamellar structures were presumed to have come from smooth-surfaced endoplasmic reticulum, and to transform to the amorphous material-triglyceride-during maturation of the lipid droplets. A true limiting membrane or membranous shell around the lipid droplet was not deceted.

Culture of cloned cells from the mouse preputial gland tumor ESR 586.

Cells from the mouse preputial gland tumor ESR 586 have been cultured and cloned. Trypsin-ethylenediaminetetraacetate was used to obtain single cells. The cells are grown in a modified CMRL-1415 medium supplemented with 10% fetal calf serum. Clones tend to fall into two classes: Class 1, those that undergo morphological differentiation in liquid medium to form round bodies filled with lipid vaculoes; and Class 2, those that do not differentiate. Preliminary studies on the control of differentiation in Class 1 clones suggest that a minimum cell density is required before differentiation takes place. Analysis of the lipids from differentiating and nondifferentiating clones reveals the presence of sebaceous-type lipids in differentiating clones only. No requirement for testosterone was found for these cells.

Ultrastructural changes and viral morphogenesis during the growth of the mouse preputial gland tumor ESR 586.

A study was undertaken to observe morphological changes and viral morphogenesis during the growth of the mouse preputial gland tumor ESR 586. The acinar cells of the normal preputial gland have an extensive agranular endoplasmic reticulum and Golgi apparatus and large lipid droplets. No viral particles are present. During tumor growth, and numerous lipid droplets never attain the size of those found in the normal gland. There is a decrease in the Golgi apparatus and agranular endoplasmic reticulum and an increase in the rough endoplasmic reticulum which could reflect a change in composition of tumor secretory product from the normal gland. Indeed, there is a decrease in triglycerides as the tumor ages and an increase in the sterol esters and waxes. In addition, intracisternal A-particles are observed budding from thickened endoplasmic reticulum membranes. Thickening of these membranes occur early in A-particle formation. One side of the membrane is first thickened while the opposing membrane appears is first thickened while the opposing membrane appears morphologically unaffected. The thickening of the affected membrane is initially confined to the outer (cytoplasmic) face of the membrane. In the older tumor, both opposing membranes of the reticulum are thickened and can assume an elongated whorled pattern.

Tumors of the pilosebaceous unit induced in the rat by the intravenous administration of 7,12-dimethylbenz(A)anthracene.

Six of 70 female Sprague-Dawley rats given a single intravenous injection of 7,12-dimethylbenz[a]anthracene (DMBA) developed 7 pilosebaceous tumors. Two of the tumors showed differentiation toward the upper portion of the pilosebaceous unit while 5 showed differentiation toward the lower portion. Each tumor was examined histochemically for the presence of inner root sheath keratin of the hair follicle using the carbamido diacetyl reaction for citrulline and for hair shaft keratin using boiling ninhydrin reagent. The 2 tumors of the upper portion of the pilosebaceous unit were sebaceous adenomas which were accompained by a keratinizing epithelim like that of the sebaceous gland duct and upper pilosebaceous canal. Histochemically, the keratin was not like that of hair shaft nor inner root sheath. The 5 tumors showing differentiation toward components of the lower pilosebaceous unit were trichoepitheliomas. They were composed of structures which, to varying degrees, recapitulated the organization of the normal hair follicle. Within these follicular structures, both inner root sheath and hair shaft type keratins were found. The occurrence of skin tumors after the intravenous administration of DMBA was unexpected since it is uncommon for skin tumors to be produced by the systematic administration of chemical carcinogens and they have never been described after the oral administration of DMBA. That the route of administration may influence tumor production with this carcinogen is suggested by the fact that the only other reported tumors, which were squamous carcinomas, also followed intravenous injection of DMBA.