Significant decreases in the intensity of staining for proteins and protein thiols in basal-cell epitheliomas (basaliomas) as compared to normal skin.

Microphotometric measurements of fast reacting protein thiols (PSHr) and proteins were performed on freshly frozen sections of samples from normal skin (26 cases as controls) and from 45 basal cell epitheliomas (basalioma; BCE). The intensity of the staining (E/micron2) for both proteins and PSHr was significantly higher in normal epidermis than in the adjacent dermis. The values of QE (quotient of values observed in the epidermis divided by those observed in the dermis) were calculated to be 3.48 for proteins (QE, Prot) and 4.62 for PSHr (QE, PSHr). In cases of BCE, significantly lower QE values were found: QE, Prot = 2.16 and QE, PSHr = 1.72. The decrease of QE, PSHr was due to a decrease in the staining intensity observed in the BCEs, whereas practically no changes occurred in the adjacent dermis. The decrease of QE, Prot was mainly caused by a decrease in the staining intensity in the BCE (by 68%) as well as in the adjacent dermis (by 36%). By dividing the mean extinction value (E/micron2) for PSHr by the E/micron2 for proteins, a new quotient, PSHr/Prot, is obtained which can serve as a quantitative measure of the content of the tissue proteins of PSHr. The proteins of normal epidermis contained more PSHr than dermal proteins. The proteins of BCEs also contained more PSHr than those of the adjacent dermis, but the PSHr/Prot values of both tissues were 1.5 to 1.6 times greater than the corresponding values for normal epidermis and dermis, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)