Previous ultrastructural and biochemical studies on ductal infiltrating carcinomas (d.i.c.) of human breast have suggested that interactions between the tumour cells and extracellular collagenous matrix are important for the invasive behaviour of these neoplastic cells (Minafra et al., 1984a(Minafra et al., ,b, 1988Pucci Minafra et al., 1985. To examine this further we have attempted to establish a breast carcinoma cell line in vitro which retains many of the properties observed in vivo. To date the majority of breast cancerderived cell lines have been obtained from secondary tumours and pleural effusions (Dobrynin, 1963;Soule et al., 1973;Trempe & Fogh, 1973;Engel & Yung, 1978;Monaghan et al., 1985). Although a cell line derived from a primary breast carcinoma has recently been reported (Vandewalle et al., 1987) the relative paucity of cell lines derived from primary carcinomas (Hackett et al., 1977;Nordquist et al., 1975; Lasfargues et al., 1978;Rudland et al., 1985) may be related to the technical difficulties associated with the extraction of viable tumour cells from surrounding stroma. Here we report the isolation, establishment and characterisation of a continuous line of neoplastic cells isolated from a primary duct infiltrating carcinoma of human breast (8701-BC). These cells have been grown in monolayer cultures for more than 100 passages and have retained morphological characteristics similar to those of the original tumour. Materials and methods Tissue fractionationTumour fragments obtained from surgical operations and histologically diagnosed as ductal infiltrating carcinoma were washed under sterile conditions with a Ca2+ and Mg2+ -free balanced salt solution (BSS-CMF). Specimens to be used for cell culture were taken from the core of the tumour, cut into very small pieces and pre-incubated in BSS-CMF with gentle stirring at 37°C for 15 min. 8701-BC cell line was derived from a G2-G3 duct infiltrating carcinoma obtained from a 72-year-old patient, with extensive lymphonodal infiltration. Histological grading was evaluated according to Bloom & Richardson (1957).Cell culture Cells of primary cultures were grown in minimum essential medium (MEM) with Earle's salts (Biochrom) supplemented with 20% (v/v) FCS (Difco) and 10% (v/v) TPB (Difco). A cell density of 1-2 x 10s cells ml-1 was used to seed primary cultures in 5ml flasks. At confluency cells were subcultured following detachment by exposure to trypsin 0.5% (w/v) and Versene 0.04% (w/v)

A retrospective histological and immunohistochemical study has been carried out in 25 cases of tick bites recorded in our Departments. The samples that included an attached tick showed a cement cone anchoring the mouthparts to the skin and a blood-soaked, spongiform appearance of the superficial dermis, with a mild neutrophilic and eosinophilic infiltration. The vessels displayed a loose multilayered endothelial proliferation, with plump endothelia, permeated with erythrocytes. A few of them were severed, allowing copious blood extravasation. The established lesions included the following: erythema chronicum migrans-like cases, foreign body granulomas-sometimes containing remnants of the mouthparts-cutaneous lymphoid hyperplasia, either of the T-cell or the B-cell type, and tick-bite alopecia. In both the T-cell and B-cell pseudolymphomas, several vessels showed concentric endothelial and perithelial proliferation similar to that seen in the acute lesions. In the tick-bite alopecia, a lymphocytic infiltrate attacked the permanent portion of the hair follicles, whose reaction was a noticeable hyperplasia of the fibrous sheaths, although only a minority of the hairs was destroyed. The observed alterations are specific in the acute lesions and in the alopecia, where they directly arise as a result of the interactions between the host's tissues and the antihemostatic, anti-inflammatory, and immunomodulatory chemicals contained in the tick saliva. In the other lesions, the changes seem less characteristic, although the fragments of mouthparts and the special vascular changes provide a clue to their etiology.

Reelin is a glycoprotein that plays a critical role in the regulation of neuronal migration during brain development and, since reelin has a role in the control of cell migration, it might represents an important factor in cancer pathology. In this study, 66 surgical specimens of prostate cancer were analyzed for reelin expression by immunohistochemical method. The reelin expression was correlated with Gleason score and individual Gleason patterns. Reelin expression was found in 39% prostate cancers. Stromal tissues, normal epithelial cells and prostate intraepithelial neoplasia (PIN) of any grade around and distant from cancer were always negative for reelin. Reelin was found in malignant prostatic epithelial glands of 50% cases Gleason score 10, 52% Gleason score 9, 56% Gleason score 8, 18% Gleason score 7, while no sample of prostate cancers with Gleason score 6 showed reelin expression (P ¼ 0,005). As reelin staining is frequently found in high Gleason score prostate cancers, we explored whether reelin expression is influenced by single Gleason patterns. While Gleason 3 pattern did not show reelin immunoreactivity, reelin expression was found in 35% Gleason 4 patterns and 45% Gleason 5 patterns (Po0.001). Our results demonstrated for the first time that reelin is expressed in prostate cancer and not in benign prostate tissue and its expression occurs in higher Gleason score and correlates significantly with increasing of single Gleason patterns. This suggests reelin may behave as a specific histological marker and may represent a useful biomarker to predict aggressive phenotypic behavior of prostatic cancer cells.

The p16INK4a gene, localized within chromosome 9p21, has been identified as a cyclin-dependent kinase inhibitor and may negatively regulate the cell cycle acting as a tumor suppressor. Genetic alterations involving the 9p21 region are common in human cancers. A consecutive series of 64 untreated patients (median of follow up 53 months) undergoing surgical resection for locally advanced laryngeal squamous-cell carcinomas (LSCCs) has been studied prospectively. Our purpose was to investigate p16 alterations (9p21 allelic loss, hypermethylation and point mutations) and their possible association with clinico-pathological data and flow cytometric variables (DNA-ploidy and S-phase fraction (SPF)), and to determine the possible prognostic role of this gene in these tumors. PCR-based techniques were used for investigating 9p21 loss of heterozygosity (LOH) and methylation promoter status of the p16 gene. p16 mutations were detected by PCR-SSCP (single strand conformation polymorphism) and sequencing. 9p21 LOH was detected in 16/62 (26%) informative tumors, point mutations in 5% (3/64) and hypermethylation in 9% (6/64) of the cases. p16 alterations were significantly associated with high SPF and DNA-aneuploidy. By univariate analysis, poor histologic differentiation, stage IV, DNA-aneuploidy and p16 point mutations proved to be significantly related to quicker relapse, whereas these same factors, and in addition high SPF, 9p21 LOH and any p16 alterations were significantly related to shorter overall survival. By Cox proportional hazards analysis only histologic grade (G3) and p16 point mutations were independently related to both disease relapse and death. Our study has identified p16 point mutations as important biomolecular indicators in LSCCs.

The putative role of TP53 and p16 INK4A tumor suppressor genes and Ras oncogenes in the development and progression of salivary gland neoplasias was studied in 28 cases of pleomorphic adenomas (PA), 4 cases of cystic adenocarcinomas, and 1 case of carcinoma ex-PA. Genetic and epigenetic alterations in the above genes were analyzed by Polymerase Chain Reaction/Single Strand Conformational Polymorphism (PCR/SSCP) and sequencing and by Methylation Specific-PCR (MS-PCR). Mutations in TP53 were found in 14% (4/28) of PAs and in 60% (3/5) of carcinomas. Mutations in H-Ras and K-Ras were identified in 4% (1/28) and 7% (2/28) of PAs, respectively. Only 20% (1/5) of carcinomas screened displayed mutations in K-Ras. p16 INK4A promoter hypermethylation was found in 14% (4/28) of PAs and 100% (5/5) carcinomas. All genetic and epigenetic alterations were detected exclusively in the epithelial and transitional tumor components, and were absent in the mesenchymal parts. Our analysis suggests that TP53 mutations and p16 INK4A promoter methylation, but not alterations in the H-Ras and K-Ras genes, might be involved in the malignant progression of PA into carcinoma.