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V M Wasenius

Publications and source records attributed to V M Wasenius.

42 records · Page 3Linked to original sources

Basement membranes in ultraviolet light-induced skin lesions and tumors.

Basement membrane changes in human skin exposed to UV irradiation were studied by light and electron microscopy and antibodies to human collagen IV and laminin were compared to similar lesions in non-sun-exposed areas. A distinct basement membrane was seen in cases of epidermal solar keratosis, even with marked dysplasia and Bowenoid type lesions, and also around most of squamous cell carcinomas which showed basement membrane irregularities, thickening and reduplication. The invading edges of the squamous cell carcinomas with inflammatory infiltrates were devoid of laminin and collagen. Basement membrane disruption was also observed in lichen planus-type solar keratosis with severe inflammation, but with no evidence of malignancy. Alterations in basement membrane structure and location were associated with cutaneous morphological abnormalities not due to UV irradiation as such.

Basement Membrane↗

Mucoepidermoid carcinoma of the thyroid.

Clinical and morphological features of three cases of primary mucoepidermoid carcinoma of the thyroid are described. The tumours were composed of two cell types. One of these resembled squamous epithelium and ultrastructurally showed tonofilaments and numerous desmosomes. The other cell type contained Alcian blue and mucicarmine positive mucin and, on electron microscopy, showed mucigen granules. Marked stromal fibrosis and psammoma bodies were seen in all tumours. Immunohistochemical studies showed that the tumour cells were negative for thyroglobulin. A few calcitonin-containing cells were seen in one metastatic tumour. One tumour showed, in addition to the histological features of mucoepidermoid carcinoma, anaplastic areas with obvious transition between the two histological patterns. The same thyroid also had a small thyroglobulin-positive papillary carcinoma in the opposite lobe. All tumours presented lymph node metastases. In two cases the primary tumour was confined within the thyroid capsule but that with anaplastic areas invaded surrounding structures. This patient died 13 months after diagnosis; the other patients are alive and symptomless one and 10 years since diagnosis. Mucoepidermoid carcinoma of the thyroid appears to be a clinicopathological entity that resembles papillary carcinoma in its natural history. The origin of the tumour is unclear. There is, however, some histological and immunohistological data suggesting that the tumour might be related to the ultimobranchial system although some histological features also appear to favour a common origin with papillary carcinoma.

Adult↗

Increased thymidylate synthase gene expression in metastatic melanoma.

Thymidylate synthase (TS) provides the only de novo source of thymidylate for DNA synthesis and is a key target for cancer chemotherapeutic agents. We investigated the TS gene expression by semiquantitative reverse-transcriptase polymerase chain reaction in metastatic melanoma and compared the results with those from control tissues. The relative TS/beta-actin level ratios were 0.5, 0.9, 0.3, 0.4, and 0.5 (mean 0.5) in skin, lymph node, thyroid, muscle, and spleen, respectively. In metastatic melanoma samples, the ratios varied from 0.9 to 2.7 (mean 2.0). The differences of expression levels between these two groups of samples were statistically highly significant (p = 0.0000713). A similar statistical significance (p = 0.0002) was observed between patients achieving a complete response and patients who had progressive disease despite immunochemotherapy. There was no clear relationship between a high TS/ beta-actin ratio and the S phase fraction, as all melanomas had a high S phase fraction.

Adult↗