Cyto - molecular Biologic Characterization of c - myc , erb B and EGF - Receptor in Squamous Cell Carcinoma / 대한피부과학회지

BACKGROUND: Oncogenes and EGF-Receptor(EGFR) may be involved n different stages of the multistep carcinogenesis process. A specific pattern of karyotypic abnormalities in solid tumors can be detected by cytogenetic methods. OBJECTIVE: This study is intnded to observe the cytomolecular kiologic chracterization of c-myc, erb B and EGFR genes in squasnous cell carcinoma(SCC) of the skin and cervix. METHODS: We have eytogenet,ically examined the short-term culturs from SCC. The rearrangement, amplification or expressi.on of erb B, c-myc, and EGFR genes were studied by Southern blot, analysis of genomic DNA and by slot blot analysis of tota! RNA extracted from biopsies of normal skin and SCC tissues. EGFR expression was examined immunohistochemially using monoclonal antibodies and the localizat,ion of the c-myc oncogene mRNA by in situ hybridization. RESULTS: A remarkably structural aberration was del 6(q21-qter) counted 20 metaphases among 28 metaphases ana1yzed. In nunierical aberration, all chromosomes were lost or gained randomly. Amenploid including triploid and tetraploid were observed in 8 metaphases, 6 tumor cells contained marker chromosome. In Southern blot analysis, rearrangement and amglificaton of EGFR in primary squamous cell carcinoma of cervix uteri and skin respectively. In slot blot analysis, the levels of c-myc, erb B and EGFR mRNA increaaed respectively 3.5, 2.5 and 2.8 times in SCC when compared to normal tissues. In immunoperoxidase stain, EGFR was present, in SCC where keratinocytes with strong cyto-plasmic staining but no membr, line labelling, where as in normal skin the were primarily present in t,he membrane and cytoplasm of basal cells. In situ hybridization with c-myc cDNAs allowed detection of grains representative of biotin labelled cDNA-mRNA hybrids in the frozden section of SCC tissues. CONCLUSION: These results suggest that specific patterns of karyotypir abnormalites, rearrangement, or amplification of EGFR gene, and overexpression of oncogenes and EGFR gene may be associated with the carcinogenesis of SCC.

Increased expression of the epidermal growth factor receptor gene in psoriasis / 대한피부과학회지

Psoriasis is characterized by disregulation of keratinocyte growth with profound epidermal hyperplasia. Keratinocyte hyperplasia in psoriasis may be expained in part by overproduction of growth factor, and by altered metabolism of the epidemal growth factor receptors (EGFR) in affected skin. The expression of epidermal growth f ictor receptor was investigated by Northern blot and slot-blot analysis of total RNA extrated from biopsies of normal skin and psoriatic lesions. In Northern blot analysis, EGFR-specific mRNA transcripts from psoriatic tissues demonstrated the specificity of hybridizarion with a EGFR mDNA probe. The size of EGFR mRNA transcript was 6.7kb in psoriasis lesions which showed no change of quality. In slot-blot analysis, the levels of EGFR mRNA in poriasis revealed a 1.2 fold to 4.1 fold elevation when compared to normal skin. EGFR were present in all epidermal layers by immunoperoxidase staining, whereas in normal skin they were primarily present in the stratum basalis. These results indicate that the increased expresion of the EGFR gene may be, in part, responsible for the hyperproliferation of the epider nis and that retained EGFR may reflect incomplet; abnormal differentiation in active porasis. This altered process of EGFR metabolism may be involved in the pathogenesis of psoriasis.

A Zosteriform Network of Eccrine Spiradenoma

Eccrine spiradenoma is clinically characterized by a solitary, movable, tender nodule occurring most frequently on the ventral surface of the upper body. A striking symptom is paroxysmal pain. Occasionally multiple lesions may be present and may occur in a linear or zosteriform pattern. A 48-year-old female was seen with painful or tender, nomal skin colored, firm nodules distributed in a zosteriform pattern on the right thigh for 10 years, which had been slowly growing. The histopathological features were quite a characteristic of eccrine spiradenoma. We report a rare case of zosteriform network of eccrine spwadenoma occurred on the right thigh.

Increased expression of the c-fos and c-myc oncogenes in psoriatic lesions / 대한피부과학회지

The expression of the c-fos and c-myc oncogenes was investigated by dot blot analysis of total RNA extracted from biopsies of normal skin and psoriatic lesions. Densitometric analysis revealed 6.3 fold and 8.6 fold evevation respectively of c-fos and c-myc oncogenes mRNA levels in severe psoriasis compared to normal skin, and 1.5 fold and 1.6 fold elevation respectively of c-fos and c-myc oncogenes mRNA levels in mild psoriasis compared to normal skin. The ratio of c-fos/c-myc transcripts in normal skin and mild psoriasis was constant compared to that in severe psoriasis. The maintenance of a constant ratio of c-fos/c-myc is believed to be closely related to ordered cell growth and the ratio of c-fos/c-myc transcripts in severe psoriasis suggests a disordered pattern of cellular differentiation. We be1ieve that overexpression of these oncogenes is related to the pathogenesis of psoriatic epidermal hyperplasia.