Sole expression of laminin gamma 2 chain in invading tumor cells and its association with stromal fibrosis in lung adenocarcinomas.

Laminin-5 (LN-5), an important basement membrane (BM) protein consisting of laminin alpha3, beta3 and gamma 2 chains, has been suggested to be involved in tumor cell invasion and tissue repair. In this study, the distribution of the LN-5 subunits in atypical adenomatous hyperplasia (AAH) and different types of adenocarcinomas of the lung was examined by immunohistochemical analysis. In AAH and non-sclerosing, well-differentiated adenocarcinomas, the LN gamma 2 chain was frequently detected along with the continuous BMs. These BMs were also positive for both LN alpha3 and beta3 chains, suggesting that LN-5 had been deposited. In contrast, the cytoplasmic staining for the LN gamma 2 chain was frequently observed in tumor cells of sclerosing, well-differentiated adenocarcinomas, as well as of moderately and poorly differentiated adenocarcinomas, without any evidence of co-expression of the LN alpha3 and beta3 chains. This staining pattern of the LN gamma 2 chain was prominent in carcinoma cells invading into interstitial stroma and was associated with the formation of a central scar in the tumor tissues. These results suggest that the LN gamma 2 chain monomer could be an important indicator of progression of lung adenocarcinoma.

[Thymidylate synthase expression in patients with hypopharyngeal carcinoma].

We analyzed the relationship between clinical response to neo-adjuvant chemotherapy including 5-fluorouracil (5-FU) in patients with hypopharyngeal carcinoma (HPC) and thymidylate synthase (TS) expression in their tumors. TS expression was evaluated with immunohistochemical staining techniques on biopsy specimens from HPC patients. TS immunostaining was divided into four levels (TS0-TS3) according to its level and pattern. The relationship between prognosis, tumor size, nodal status, differentiation of tumor cells and TS expression were also investigated. There was a statistically significant association between the level of TS expression and tumor size (p < 0.01). In terms of the effectiveness of chemotherapy, tumor differentiation, nodal status and prognosis, a statistical difference was not found in TS expression. These results suggest that the level of TS expression may show the degree of tumor proliferation, but may not necessarily be useful to obtain a response to chemotherapy including other drugs, e.g., cisplatin and other derivatives of platinum.

[Case reports of mucosal melanoma of the head and neck].

Twelve patients with mucosal melanoma in the head and neck were treated at Yokohama city University from 1975 to 1994. The sex distribution was 5 male and 7 female, and the age ranged from 40 to 79 years-old. The highest number of patients were in their sixties. In 10 cases tumors arose in the nasal cavity, in one case in the maxillary sinus and in other case in the oral cavity. The treatment modality for this tumor consisted of various combination therapies including surgery, radiotherapy, chemotherapy and immunotherapy. Combination chemotherapy consisting of dimethyltriazeno imidazole carboxamide (DTIC, Dacarbazine), amino methyl pyrimidinyl methyl chlorethyl nitrorosourea hydrochloride (ACNU) and vincristine (VCR). Cisplatin (CDDP) was recently used for cases where other chemotherapy was not effective. Surgical treatment in the initial therapy was performed in 8 patients. In three of these 8 cases, the surgical margin was positive. One of them was dead after 9 months, another dead with complication after 1 year and the other survived free of any tumor. Immunotherapy using OK-432, interleukin-2, LAK therapy and low dose CPM was effective for some patients. The 5-year survival rate was 44%. Patients with surgical treatments in the initial therapy had longer survival than those without surgical treatments.

Expression of new members of the prolactin growth hormone gene family in bovine placenta. Isolation and characterization of two prolactin-like cDNA clones.

Two prolactin-like proteins (bPLP-I and bPLP-II) were deduced from the nucleotide sequence analyses of the cDNA clones derived from a bovine (Bos taurus) term placenta. These proteins resembled bovine prolactin but were different from the reported bovine placental lactogens or prolactin-related proteins. The predicted amino acid sequences of these clones showed 45-51% identity with bovine prolactin and 23-24% with bovine growth hormone. The two new clones show 62 and 39% overall homology with each other at the levels of nucleotide and amino acid sequences, respectively. bPLP-I, bPLP-II, placental lactogens, prolactins (PRLs), and other prolactin-like proteins isolated from cow, mouse, and rat share 7 common amino acid residues. Five of the 7 residues are conserved by other members of the family such as growth hormones, suggesting that they may be essential for the common structural features of the gene family. The other 2 residues are uniquely conserved in bovine, mouse, and rat placental lactogens, PRLs, and PRL-like proteins, predicting their indispensable roles in binding to the specific receptors. bPLP-I and bPLP-II, as well as bPLP-III, are shown to be expressed stage specifically and predominantly in full-term bovine placentas.