involucrin and Keratoacanthoma

The F1F0-ATP synthase, an enzyme complex, is mainly located on the mitochondrial inner membrane or sometimes cytomembrane to generate or hydrolyze ATP, play a role in cell proliferation. This study focused on the role of F1F0-ATP synthase in keratinocyte differentiation, and its relationship with intracellular and extracellular ATP (InATP and ExATP). The F1F0-ATP synthase β subunit (ATP5B) expression in various skin tissues and confluence-dependent HaCaT differentiation models was detected. ATP5B expression increased with keratinocyte and HaCaT cell differentiation in normal skin, some epidermis hyper-proliferative diseases, squamous cell carcinoma, and the HaCaT cell differentiation model. The impact of InATP and ExATP content on HaCaT differentiation was reflected by the expression of the differentiation marker involucrin. Inhibition of F1F0-ATP synthase blocked HaCaT cell differentiation, which was associated with a decrease of InATP content, but not with changes of ExATP. Our results revealed that F1F0-ATP synthase expression is associated with the process of keratinocyte differentiation which may possibly be related to InATP synthesis.

Topics: Adenosine Triphosphate; Carcinoma, Squamous Cell; Cell Differentiation; Cell Line, Transformed; Dermatitis; Gene Expression Regulation; Humans; Keratinocytes; Keratoacanthoma; Keratosis, Seborrheic; Mitochondria; Mitochondrial Membranes; Mitochondrial Proton-Translocating ATPases; Protein Precursors; Prurigo; Psoriasis; Skin; Skin Neoplasms; Warts

Topics: Carcinoma, Squamous Cell; Diagnosis, Differential; Humans; Immunohistochemistry; Keratins; Keratoacanthoma; Protein Precursors; Skin Neoplasms

The case of a 60-year-old Japanese man with unique multiple keratoacanthomas is reported. The lesions were located in the perioral area, grew peripherally, and healed centrally. Although individual lesions spontaneously regressed, prompt recurrence was observed after excision. Biopsy specimens taken from early proliferative, fully developed, and regressing stages revealed keratoacanthoma. Involucrin was demonstrated in the lesions during development and resolution. The early stage showed homogeneous staining of moderate intensity in the tumor cells at the suprabasal layers, and the staining became slightly irregular and intense when the lesions were fully developed. During resolution the intensity was markedly diminished. These results suggest that preterminal squamous differentiation accelerated during development of the tumors.

Topics: Diagnosis, Differential; Facial Dermatoses; Humans; Keratoacanthoma; Male; Middle Aged; Protein Precursors; Recurrence

The expression of involucrin was examined in 23 skin tumours of hair follicle origin, 17 tumours of sweat gland origin and three tumours of unknown origin, using an immunoperoxidase technique. All tumours from the hair follicle showed a positive reaction for involucrin. In particular keratoacanthoma and the squamous eddies in various tumours stained strongly. Trichofolliculoma, trichilemmoma and pilomatrixoma exhibited characteristic staining patterns which resembled those in the normal hair follicle. On the other hand the majority of the tumours of sweat gland origin did not stain, with restricted positive reactions in areas showing lumen formation or squamous metaplasia. In contrast to the lack of staining in syringoma, a positive reaction was observed in desmoplastic trichoepithelioma, which is histologically similar to syringoma. Clear cell acanthoma, the origin of which is still controversial, showed a staining pattern which indicated that its origin may not be in the sweat gland. These results suggest that testing for involucrin in skin appendage tumours may be very useful for understanding the kinetics of maturation as well as in determining the origin of the tumours.

Topics: Carcinoma, Squamous Cell; Cystadenoma; Hair; Hair Diseases; Humans; Immunoenzyme Techniques; Keratoacanthoma; Protein Precursors; Skin Diseases; Skin Neoplasms; Sweat Gland Neoplasms; Sweat Glands

We examined seven invasive squamous cell carcinomas, five squamous cell carcinomas in situ, four keratoacanthomas, two actinic keratoses, and two seborrheic keratoses by indirect immunofluorescence. We used a panel of three antibodies: one directed against filaggrin, one against involucrin, and one against peptidylarginine deiminase. Anti-involucrin stained all the lesions studied, but the pattern within a given category of lesions was variable and consistent differences between the categories were not observed. Similarly, the antibodies against peptidylarginine deiminase and filaggrin were not able to distinguish differences between the various types of tumors. We conclude that in tumors of epidermis, benign or malignant, products of differentiation are expressed independently of histologic atypia or clinical aggressiveness. Therefore, markers of differentiation do not appear to be reliable indexes for distinguishing benign from malignant lesions.

Topics: Carcinoma, Squamous Cell; Filaggrin Proteins; Fluorescent Antibody Technique; Humans; Hydrolases; Intermediate Filament Proteins; Keratins; Keratoacanthoma; Precancerous Conditions; Protein Precursors; Protein-Arginine Deiminase Type 4; Protein-Arginine Deiminases; Skin; Skin Neoplasms

Fifteen keratoacanthomas and fifteen squamous cell carcinomas of the skin were examined by immunoperoxidase methods for involucrin and both 45- and 63-kilodalton keratins. Keratoacanthomas showed a relatively homogeneous staining pattern for involucrin; all cells except basal cells stained with mild to moderate intensity. Squamous cell carcinomas disclosed a highly irregular involucrin staining pattern with marked variation in staining intensity from cell to cell. Staining patterns for keratin proteins did not appear to distinguish between keratoacanthomas and squamous cell carcinomas. The 45-kilodalton keratin pattern showed diffuse staining within both keratoacanthomas and squamous cell carcinomas, and the 63-kilodalton keratin pattern consisted of focal staining, mostly of dyskeratotic cells. These results suggest that involucrin may serve as a diagnostic aid in differentiating between squamous cell carcinomas and keratoacanthomas. In addition, other lesions in the differential diagnosis of keratoacanthoma and squamous cell carcinoma were also examined for involucrin.

Topics: Adult; Aged; Carcinoma, Squamous Cell; Epidermis; Histocytochemistry; Humans; Immunoenzyme Techniques; Keratins; Keratoacanthoma; Middle Aged; Neoplasm Proteins; Protein Precursors; Sebaceous Glands; Skin Diseases; Skin Neoplasms; Sweat Glands