Incidence of Breast Cancer in Piedmont: 1979–1981

A population-based survey of histologically diagnosed breast cancer was carried out among residents in Piedmont. A total of 5267 incident cases occurring in 1979–1981 was collected, corresponding to an age-standardized (on the world population) incidence rate of 49.5/100,000 per year. Rates (standardized on the population of Piedmont in 1981) were highest in the city of Torino (112.4/100,000 per year) and lowest in the province of Cuneo (67.5), whereas in the other provinces they ranged between 85.3 and 90.0. Estimation of rates in the 54 Local Health Authorities of Piedmont detected up to 2-fold differences between adjacent areas. A correlation was found between rates and size of the population of town of residence. Comparison with age-specific incidence rates from the Cancer Registry of the nearby province of Varese suggested a loss of nonhistologically confirmed cases selectively in older age groups. The distribution of cases diagnosed in 1979 by histologic type is presented. The proportion of diagnoses reported in terms which were consistent with the 1978 WHO Histological Typing of Breast Tumours was 61.3%. It was highest among cases identified in Pathology Services located in University Hospitals and/or diagnosing more than 50 breast cancers per year.

Risk of Breast Cancer, Diet and Internal Migrations in Northern Italy

The protective effect of birth in southern Italy as opposed to other regions was evaluated in a population-based case-control study of diet and breast cancer among residents In the province of Vercelli. Cases were 250 women with breast cancer diagnosed during 1983-1984 and controls 499 women randomly selected from the general population. The crude relative risk of breast cancer for women born in the south was 0.76 (95% confidence interval, 0.43-1.3). After adjustment for dietary and other potential confounders in multivariate analyses, the protective effect of place of birth disappeared (RR 1.0; 95 % CI, 0.57-1.9). The study indicates that north-south differences in the incidence of breast cancer in Italy may in large part be attributed to different dietary habits.

Cancer of the Breast in Women Born in Southern Italy and who Migrated to the City of Torino

Individual demographic data of 459 women living in Torino with incident breast cancer diagnosed in 1979 were compared with those of a random sample of 1800 women drawn from the list of residents in the same city. Among women aged 25–44 and 45+ years, age-adjusted odds ratios for birth in southern Italy were respectively 1.3 (95% CL, 0.1–2.1) and 0.7 (95% CL, 0.5–0.9). In women aged 45+ years, odds ratios increased with length of residence in Torino.

High Incidence of Laryngeal Cancer in the Province of Torino (Italy)

The present report shows that the province of Torino, Italy, (6830 sq Km, population in 1966, 2.074.893) is a high risk area for laryngeal cancer. A total of 875 cases occurring in residents in the province were forwarded to the Cancer Registry of Piedmont (RTP) in 1965–69. A histological report was available in 67.9 % cases, while in 21.8 % the death certificate was the only document with diagnosis of laryngeal cancer (table 1). Cases were uniformly distributed throughout the 5 years covered by the study: the number of cases with death certificate only progressively decreased from 59 in 1965 to 21 in 1969 (table 3). For the purposes of the present study, the province of Torino has been divided into 3 areas, i.e. the city of Torino (population 1.107.919), the 23 suburbs (total population 340.951) and the non-metropolitan part of the province (population 626.023). Among the three areas, the relative frequency of laryngeal cancer/all malignant tumours recorded at the RTP in men was 5.78 % in the city of Torino, 6.43 % in the suburbs and 4.77 % in the non-metropolitan part of the province (table 4). The difference between the city of Torino and the suburbs was not significant (p > 0.05) while the difference both between the city of Torino and the non metropolitan part of the province and between the suburbs and the non metropolitan areas was significant (p < 0.05 and p ∼ 0.01 respectively). In other cancer registries (3) the relative frequencies of laryngeal cancer were under 2.86 % with the exception of Israel (3.24 %) and Bombay (9.26 %). In women, the relative frequency of laryngeal cancer fluctuated between 0.25 and 0.32 % in the different areas of the province of Torino, i.e. in the same order of those observed in other cancer registries with the exception of Bombay (2.07%) (3). In the province of Torino considered as a whole, age standardized annual incidence/100.000 of laryngeal cancer was 12.6 in men and 0.6 in women. Incidences truncated to ages 35–64 were 25.5 and 0.9 respectively (table 5). In men these rates are approximately 5–7 times higher than those recorded in Norway, Sweden and Denmark and about 3.5–6 times higher than those recorded in the six cancer registries operating in Great Britain. A comparison between the province of Torino and other cancer registries on age specific incidences (table 6, text-fig. 3) shows that the ratio province of Torino/other registries is relatively higher at age 35–44 than later in life. This is considered as evidence of an increase of the environmental carcinogenic load in the province of Torino during recent years. In men, age standardized incidences and incidences truncated to ages 35–64 were slightly but not significantly higher in the city of Torino than in the suburbs. On the other hand, in both the city of Torino and the suburbs they were 1.5–1.7 times higher than in the non-metropolitan part of the province (table 5). The difference concerned mainly age groups over 55 (text-fig. 2). However, the incidence of laryngeal cancer truncated to ages 35–64 in the non-metropolitan part of the province of Torino was still 7.2 times higher than in the rural population of Norway and 2.1–4.1 times higher than in the six cancer registries operating in Great Britain (3). This suggests that factors connected with life in the metropolitan area of Torino (such as air pollution) are a minor cause of the excess of laryngeal cancer in the province of Torino.

Evidence for a second tumor suppressor gene on 17p linked to high S-phase index in primary human breast carcinomas

The short area of chromosome 17 is a frequent target for deletions in human tumors, including breast cancer. We have investigated by restriction fragment polymorphism analysis the pattern of loss of heterozygosity (LOH) at four loci on 17p13.1-17pter in a panel of 110 primary human breast carcinomas. A copy of the p53 gene was lost in 23% of the informative cases. Point mutations in the p53 gene were statistically associated with LOH at the same locus (p = 0.003) but not at other loci on 17p13.3-17pter. A second region bordered by the loci D17S5/D17S28 (17p13.3) and D17S34 (17pter) is also affected by LOH, independent of point mutations in the p53 gene. We propose the presence of a second tumor suppressor gene within this region. In support of this hypothesis is the significant association (p = 0.005) between LOH at the D17S5/D17S28, but not at the TP53 or D17S34 loci, and tumors having a high S-phase index.

Genetic and molecular heterogeneity of breast cancer cells

We have undertaken a systematic study of primary human breast tumor DNAs to identify and characterize frequently occurring somatic mutations. Loss of heterozygosity (LOH) was found on chromosomes 1p (37%), 1q (20%), 3p (30%), 7 (41%), 13q (30%), 17p (49%), 17q (29%) and 18q (34%) in our tumor DNA panel. Specific subsets of tumors could be defined based on the particular collection of mutations they contained. One goal of these studies has been to determine whether there is a significant association between specific mutations and clinical parameters of the disease. We have found that LOH on chromosome 17p in tumor DNAs is associated with breast tumors having a high proliferative index and that LOH on chromosome 7 is associated with patients having a poor prognosis. Our analysis of chromosome 17 suggests that there may be as many as four tumor suppressor genes affected in primary human breast tumors.

In primary human breast carcinomas mutations in exons 5 and 6 of the p53 gene are associated with a high S-phase index

A series of 121 human breast tumors was screened for point mutations in exons 5 through 8 of the p53 gene, by SSCP analysis. On the same tumor samples, the S-phase index (SPI) was determined by the incorporation of BUdR in fresh tissue. p53 mutations were observed in 29% of the cases. The frequency of point mutations for the individual exons was: exon 5, 10.0%; exon 6, 9.9%; exon 7, 7.1% and exon 8, 5.5%. Two mutations detected by SSCP were confirmed by sequencing the p53 cDNA. The presence of a p53 mutation, irrespective of its location, correlates (p = 0.003) with a high SPI. This association appears to primarily reflect mutations in exon 5 (p = 0.0002) and exon 6 (p = 0.05), since mutations in exons 7 and 8 failed to show any association. These results indicate that mutations in the p53 gene identify highly proliferating tumors, and that the position of the p53 mutation may have different effects upon the proliferative activity of tumor cells in vivo.

Survival of breast cancer patients from Piedmont, Italy

A population-based series of 4,764 women from Piedmont, Italy, who were diagnosed with breast cancer during 1979-81 and for whom information on social and demographic factors was available, was followed-up for mortality until 1986 or 1987. Relative survival rates at one, three, and five years were 94.6, 81.6, and 71.1 percent, respectively, and were similar to those of other European series. Women aged 40-49 years at diagnosis experienced a better survival than women in other age groups. The mortality was highest between one and four years after diagnosis, and lowest between five and seven years. Survival rates were lowest for women above the age of 80, and single women had a worse prognosis than married women. Women with less than seven years of education had nonsignificantly lower survival rates than more educated women. No difference in survival was found according to occupation, size of town of residence, place of birth, or type of hospital.

Cell proliferation of breast cancer evaluated by anti-BrdU and anti-Ki-67 antibodies: its prognostic value on short-term recurrences

The prognostic value of breast cancer proliferative activity was evaluated in 385 women operated for primary, non-metastasised mammary carcinoma. Cell kinetics was measured using two immunohistochemical techniques. Cells in S-phase of cell cycle were labelled in vitro by incubation of fresh tissue fragments with 5-bromo 2-deoxyuridine (BrdU), a thymidine analogue. Nuclei of cells in active DNA synthesis were stained by an anti-BrdU monoclonal antibody (Mab). Cells in interphase and mitosis were detected with Ki-67, a Mab that is known to react with a nuclear antigen present in G1/S/G2/M phases of cell cycle, but not in resting cells. This reagent provides a means of evaluating the growth fraction of neoplastic cells. BrdU was incorporated in a proportion of tumour cells ranging from 0.1 to 65.5% (median 6.8%). In the panel of tumours presented in this report the median percentage of Ki-67 positive cells (Ki-67 score) was 9.0% (range 0.1-77%). The relationship between disease-free survival (DFS), BrdU labelling index, Ki-67 score and 13 different clinico-pathological variables was investigated by multivariate analysis, using the Cox proportional hazards model. Axillary node status (P = 0.009) and Ki-67 score (P = 0.038) emerged as independent prognostic factors. Nodal status and tumour growth fraction allowed division of patients into groups at different risk of relapse: tumours with a proliferative index below the median value showed a lower recurrence rate than tumours with a high proliferative activity (P < 0.001). In particular, no relapse occurred in pN0 patients bearing carcinomas with a Ki-67 labelling < 9.0% 4 years after surgery. These findings suggest that the evaluation of proliferative activity in breast cancer enhances the probability of correctly predicting outcome after surgery and could be of assistance in the planning of adjuvant therapies.

Growth and motility of microvascular endothelium are modulated by the relative concentration of gangliosides in the medium

The data reported were obtained as an attempt to understand whether the change in total concentration and relative ratios of the 3 major corneal gangliosides (GM3, GM2, GD3) previously observed in corneas stimulated by an angiogenic molecule (Ziche et al., 1989) was a relevant event in the angiogenic response of the tissue. The effect on endothelial cell growth was tested for the 3 corneal gangliosides added singly to the culture medium, and GM3 was found to possess a substantial growth inhibitory effect as compared to GM2 and GD3. The growth-limiting effect of GM3 was counteracted to a different degree by the addition of a second ganglioside to the culture medium. A mixture of GM3 + GM2 + GD3 in the proportion similar to that found in the cornea stimulated by an angiogenic molecule was able to sustain a sharp increment in cell growth and motility when added to cultures of capillary endothelium. On the contrary, when the 3 components of the mixture were in the proportion present in the normal cornea, the increment in growth or motility did not occur. A simple change in the relative proportions of the 3 gangliosides was sufficient to trigger or prevent an increment in growth and motility of the endothelial cells. These data in vitro suggest that the changes in concentration and relative ratios of the 3 major corneal gangliosides observed in vivo when the cornea was stimulated by an angiogenic molecule were an event targeted to favour growth and mobilization of the capillary endothelium located within the limbal vessels at the periphery of the cornea.

Somatic mutations and human breast cancer. A status report

A systematic study of primary human breast tumor DNA demonstrated that three proto-oncogenes or regions of the genome (c-myc, int-2, and c-erbB2) are frequently amplified and that there is loss of heterozygosity (LOH) on chromosomes 1p(37%), 1q(20%), 3p(30%), 7(41%), 11p(20%), 13q(30%), 17p(49%), 17q(29%), and 18q(34%). Specific subsets of tumors can be defined based on the particular collection of mutations they contain. For instance, LOH on chromosomes 11p, 17p, and 18q frequently occurs in the same tumor. A search for putative tumor suppressor genes within the regions of the genome affected by LOH has been started. In a comprehensive molecular analysis of the p53 gene on chromosome 17p, 46% of the tumors contained a point mutation in the p53 gene.

Loss of heterozygosity on chromosome 17p13 in breast carcinomas identifies tumors with high proliferation index

The capacity of breast tumor cells to proliferate is considered a potential prognostic factor together with other histopathologic parameters. The authors determined the proliferation index on a large panel of human primary breast tumors by measuring the levels of incorporation of bromodeoxyuridine (BrdU) by fresh tumor specimens in culture. Previous analysis showed that the percentage of cells entering the S-phase of the cell cycle strongly correlates with tumor grade, tumor size, and estrogen and progesterone receptor status. The capacity of tumor cells to proliferate might be associated with specific genetic mutations in primary tumors. To test this hypothesis, a panel of 96 human breast carcinomas, for which the BrdU labeling index (LI) was known, were tested for loss of heterozygosity (LOH) or increased copy number (ICN) at chromosomes 1q, 3p, 13q, 17p, and 18q. On chromosome 17p, LOH and ICN were observed in 27% and 12%, respectively, of the informative breast tumors. The LOH on chromosome 17p was significantly associated with tumors having an elevated BrdU proliferation index (P = 0.022). No association (P = 0.45) was observed between BrdU LI and tumor size (T2 + T3 compared with T1), tumor grade, and lymph node status. Increased copy number on chromosome 17p, LOH or ICN on 1q, and LOH on 13q14, 18q, and 3p also showed no significant correlation with cell kinetic parameters. These data are consistent with the presence of a gene or genes on chromosome 17p13 near the YNZ22.1 locus whose normal functioning is necessary for controlling breast tumor cells proliferation in vivo.

Mutations in the p53 gene in primary human breast cancers

Twenty-six primary breast tumors were examined for mutations in the p53 tumor suppressor gene by an RNase protection assay and nucleotide sequence analysis of PCR-amplified p53 complementary DNAs. Each method detected p53 mutations in the same three tumors (12%). One tumor contained two mutations in the same allele. Single strand conformation polymorphism analysis of genomic DNA and complementary DNA proved more sensitive in the detection of mutations. Combining this technique with the other two a total of 12 mutations in the p53 gene were demonstrated in 11 tumors (46%), and a polymorphism at codon 213 was detected in another tumor. Loss of heterozygosity on chromosome 17p was detected by Southern blot analysis in 30% of the tumor DNAs. Not all of the tumors containing a point mutation in p53 also had loss of heterozygosity of the remaining allele, suggesting that loss of heterozygosity may represent a later event.

A community study of alcohol consumption and dietary habits in middle-aged Italian women

This population-based study examines whether dietary intake in middle-aged Italian women is influenced by alcohol drinking habits. The 499 participants were interviewed using a dietary history questionnaire designed to investigate alcohol consumption. Mean intake of total and non-alcohol energy increased progressively within categories of increasing alcohol consumption (less than 5, 5-19, 20-39, 40+ g/day). Mean body weight and Quetelet index (kg/m2), however, decreased with increasing alcohol consumption. Once the disparities in energy intake were reduced by computing intake densities, the data suggest that moderate and heavy drinkers have dietary habits similar to those of abstainers or light drinkers. These findings were confirmed by multiple linear regression analyses in which the confounding effects of age, place of residence, occupation, and Quetelet index were taken into account. Increasing alcohol consumption appeared associated only with a modest decrease in the intake of fibre, beta-carotene, and vitamin C. These findings do not support the hypothesis that the observed protection from coronary artery disease among moderate drinkers is related to a chronic reduction in the intake of carbohydrates and fat, at least in middle-aged women.

[Tyrosine-phosphorylated proteins in human breast carcinoma]

Proteins phosphorylated on tyrosine are detectable by antibodies against phosphotyrosine (P-Tyr antibodies) in cells transformed by oncogene-encoded tyrosine kinases. We used P-Tyr antibodies to investigate the existence of abnormal levels of phosphoproteins in human breast cancer. Three human breast cancer cell lines (SK-BR-3, MCF-7 and CG-5) and 37 human breast cancer specimens were examined by Western blot analysis and "in vitro" kinase assay. In the SK-BR-3 cell line three major phosphoproteins of the approximate Mr of 185,000 (p185), 135,000 (p135) and 110,000 (p110) were detected. The former was identified as the HER-2 gene product by specific antibodies against HER-2 encoded protein. In the other cell lines, a product of the approximate Mr of 170,000 (p170), together with a p135 and a p110, were phosphorylated on tyrosine. P185 and p170 were shown to have an associated tyrosine kinase activity. Two proteins, comigrating with p135 and p110, were found to be highly phosphorylated on tyrosine in 50% of the breast cancer samples, but not in samples harvested from 12 human tumors of the gastro-intestinal tract. These data show that 50% of human breast cancer samples display an abnormal level of tyrosine phosphorylated proteins.

Synergism between gangliosides and basic fibroblastic growth factor in favouring survival, growth, and motility of capillary endothelium

The experiments reported were motivated by the observation that in vivo gangliosides promoted angiogenesis when the dose of the angiogenic factor was too low to be effective (Ziche et al.: Laboratory Investigation 61:629-634, 1989). As an approach to understanding the mechanism of this modulatory effect, we analysed the influence that gangliosides have on survival, growth, and migration of capillary endothelium when an angiogenesis factor like basic fibroblast growth factor (bFGF) was present in the culture medium. Clones of bovine capillary endothelium were cultivated in media unable to sustain survival over a 72 h period. With this experimental approach, cell survival was evaluated after addition of either bFGF or gangliosides or both to the medium. The Boyden chamber procedure was utilized to measure the influence of bFGF or gangliosides on cell mobilization across a micropore filter. Low doses of both molecules, ineffective when added singly to the culture media, improved all three parameters when added in combination. A synergic effect between bFGF and the gangliosides (GM1, GD1b, GT1b) was observed for the improvement of survival or growth and for the acceleration of endothelial cell migration. The removal of sialic acid from the ganglioside molecule prevented any effect on all three parameters. The addition of sialic acid alone to cultures was also totally ineffective. In the adult organism most angiogenic events occur under conditions of tissue damage. The synergism between gangliosides and bFGF can be interpreted as the initial phase of a process for which endothelial cell survival is the indispensable first step in the formation of a new vascular network.

Late cytokinetic abnormalities in irradiated rectal mucosa

Late cytokinetic changes of the colonic crypt epithelium after radiation therapy were investigated. A monoclonal antibody to bromodeoxyuridine (anti-BrdU MAb) was used in tissue specimens previously incubated with BrdU to show S-phase cells by immunohistochemical technique. Endoscopic rectal biopsies were taken from 30 patients previously treated with radiotherapy for gynaecological cancer and from 50 patients with comparable but untreated neoplasms, as controls. Number and height distribution of S-phase cells were evaluated by dividing each crypt column into 5 equal longitudinal compartments. No statistically significant differences were found in total Labelling Index (LI) between controls and irradiated mucosa, whereas LI per crypt compartment, percentage of labelled compartments and percentage of BrdU-positive cells in the middle and superficial portions of the crypt were significantly higher in patients submitted to radiation therapy. This kinetic abnormality corresponds to a progressive shift of the major zone of DNA synthesis to the upper third of the crypt as a late reaction to radiation and represents an early step in the histogenesis of colorectal cancer. These results lend support to the view that there is a higher risk of colorectal carcinoma after pelvic irradiation.

Characterization by monoclonal antibody of a highly conserved antigenic determinant expressed on human platelet membranes and intermediate filament type III

The murine monoclonal antibody (MoAb) CB21, raised after immunization with sonicated extracts of human platelets, has been shown to react with a line-restricted surface molecule and also a cytoplasmic structure displaying no restriction in terms of lineage and species. The surface structure recognized by the CB21 MoAb is exclusively expressed on the surface membrane of human platelets, being undetectable on other cells or lines so far tested. After permeabilization, the majority of the cells and lines tested with the CB21 MoAb displayed strong cytoplasmic reactivity with a constant typical filamentous distribution. Biochemical and morphological analyses showed that the cytoplasmic counterpart recognized by the CB21 MoAb is the intermediate filament type III.

Breast cancer and alcohol consumption: a case-control study in northern Italy

From 1983 to 1986, a population-based case-control study of alcohol and breast cancer (250 cases and 499 controls) was conducted in a grape-farming area of northern Italy, where wine consumption is widespread. In the study population, 30% of women were abstainers and 15% reported alcohol intakes of 30 g/day or more. After adjustment for potential confounders, no appreciable association was evident for alcohol consumptions as high as 40 g/day. Women reporting intakes of more than 40 g/day showed approximately a 2-fold increase in the risk of breast cancer (relative risk, 1.9; 95% confidence interval, 1.1-3.3). A 2-fold increase in risk was observed for consumptions of more than 40 g/day of alcohol from wine, the most common alcoholic beverage in this population. These findings suggest that an association between alcohol intake and breast cancer may exist. However, the moderate risk observed seems to be limited to the relatively small group of women consuming daily amounts of alcohol in excess of 40 g, the equivalent of about half a bottle of wine or more.

Defective T-cell activation by Mycoplasma arthritidis mitogen is restored by interferon-gamma

A mitogen derived from supernatants of Mycoplasma arthritidis (MAS) has been shown to induce both T-cell activation and the production of interferon-gamma (IFN-gamma). MAS-induced response required the presence of accessory cells and is under the genetic control associated with the major histocompatibility complex (MHC). We found that recombinant IFN-gamma restored the proliferative response to MAS mitogen in unreactive mice strains, including H-2b and H-2s haplotypes. We postulated that these T-cells fail to respond since they lack part of the I-E molecules on their accessory cells. Our data suggest that interferon-gamma may be able not only to increase the levels of Ia antigens but also to promote the appearance of MHC products that are not usually present on the cell surface. Since Ia antigens have a central role on T-cell activation, we examined the effect of the level of IFN-gamma on MAS-induced T-cell activation. We analyzed the acquisition of responsiveness to IL-2 and IL-2 activity in cells pretreated with IFN-gamma and found that both the steps of T-cell activation were restored to the MAS mitogen in the unreactive mice strains by IFN-gamma.

Calorie-providing nutrients and risk of breast cancer

A case-control study was conducted in Italy to investigate the role of diet in breast cancer. Cases were 250 women with breast cancer, and controls were a stratified random sample of 499 women from the general population. A dietary history questionnaire was used to measure the intake of total fat, saturated fat, animal proteins, and other macronutrients. In multivariate analyses, the relative risks of breast cancer for women in the highest quintile of consumption of saturated fat and animal proteins were 3.0 (95% confidence interval, 1.9-4.7) and 2.9 (1.8-4.6), respectively. A reduced risk was found for women who derived less than 28% of calories from fat versus greater than 36%. A similarly reduced risk was found for women who derived less than 9.6% of calories from saturated fat or less than 5.9% from animal proteins. These data suggest that during adult life, a reduction in dietary intake of fat and proteins of animal origin may contribute to a substantial reduction in the incidence of breast cancer in population subgroups with high intake of animal products.

Generation and selection of monoclonal antibodies identifying surface molecules discriminating between fetal and adult fibroblasts

The present report describes the reactivity of two murine monoclonal antibodies, i.e., CB11 and CB43, the first obtained by using embryonic material as immunizer and the second elicited against a human cell line. These reagents recognize two distinct molecules marking a peculiar differentiation stage on fetal/embryonic fibroblasts. The first structure is a single chain of 14.5 kd, the second one a heterodimer of 40-80 kd. Even if these reagents are not strictly fibroblast restricted, translineage expression does not diminish the medical relevance of the reagents; in fact, they may have application in prenatal diagnostics and amniocentesis testing, in which it is necessary to discriminate between fetal and maternal cells.

Different substrates influence the expression of intermediate filaments and the deposition of basement membrane proteins

A primary culture of serous cystadenocarcinoma of the ovary was used to study the expression of intermediate filament proteins and the deposition of basal lamina proteins. It was found that cells grown on type I and IV collagens or in collagen gels failed to express vimentin, which was readily demonstrable in cultures of the same cells grown on plastic or glass. Furthermore cells grown in collagen gels formed colonies demonstrating a cystic architecture. Unlike what is commonly observed on glass or plastic, where laminin and fibronectin are deposited as disorganized fibrils in the extracellular space, in or on collagen these proteins appear solely at the interface between the epithelial cells and matrix. The results suggest that the extracellular matrix influences the cytoskeletal organization of the intermediate filaments and determines cell polarity. They confirm that collagen substrates permit epithelial cell cultures to progress toward a more differentiated state.

Expression of the monoclonal antibody-defined CAR-3 epitope on neoplastic and preneoplastic lesions of the colon mucosa

The AR-3 monoclonal antibody, which defines the tumor-associated antigen CAR-3, was previously found to be able to discriminate between neoplastic cells in gastric, pancreatic, colonic, ovarian and endometrial carcinomas and their normal counterparts. In fact, it strongly reacts with carcinomatous cells at the level of both the glycocalix and the cytoplasm, while its reactivity with normal tissues is restricted to the glycocalix of few mucin-producing epithelial cells. We have now investigated the reactivity of this antibody with immunohistochemical techniques on a series of formalin-fixed paraffin-embedded specimens, from precancerous and cancerous lesions of the large bowel which were classified as adenomas with mild, moderate or severe dysplasia, adenomas with cancer and adenocarcinomas, respectively. It was found that the intensity and extent of the staining correlated with the degree of dysplasia and that the highest expression of the CAR-3 epitope was detectable in adenocarcinomas. Also the localization of the staining in the lesions displayed an increasingly complex pattern, going from linear in adenomas with mild dysplasia to a very strong intracytoplasmic and/or intraluminal expression in adenomas with severe dysplasia or adenocarcinomas.

Definition by CB12 monoclonal antibody of a differentiation marker specific for human monocytes and their bone marrow precursors

The CB12 monoclonal antibody, which reacts with a molecule expressed on monocytes, was characterized using human embryonic material as immunizer. Analysis of the monoclonal antibody at the phenotypic, molecular, and functional levels indicates that its reactivity is restricted to circulating monocytes and their precursors in the bone marrow, whereas it is undetectable on tissue macrophages. CB12 displays a pattern of reactivity compatible with that of a marker of monocyte differentiation. Preliminary data indicate a possible receptor role for the CB12 molecule.

Histyocitic Tumors of the Soft Tissues

Tumors of the soft tissues are very various; they reproduce only partly the characteristics of the tissues of origin and present many modulations due principally to the stage of differentiation. The definition of these lesions must be precise as the different groups have quite unlike behavior and require an appropriate treatment. They are usually classified as tumor-like lesions, benign neoplasms, malignant neoplasms. This classification, however, is not sufficient for a precise prognostic and theraphy as there are behaviour anomalies, such as tumors which grow by infiltration and do not metastasize and encapsulated tumors which develop metastases. For instance, every mesenchymal tumor grows into the skin by infiltration but only few of them produce metastasis; some fibromatosis are true neoplasms which may display insidious infiltrative growth and frequently recurrence appears after the removal but there are no metastases. Sarcomas of varying histological types may have a different behavior requiring a different form of treatment. New knowledge on tumors of the soft tissues is due essentially to the combination of research by «in vitro» culture and clinical-pathological studies. The demonstration of the histogenesis of some tumors allowed the reclassification of fibrous growth deriving from facultative fibroblastic cells. These tumors are composed of fibroblasts with a xanthomatous component, giant cells and phagocytic foam cells: histogenetically they are histiocytic fibroblasts. Istiocytes may behave as fibroblasts or fagocytes and sometimes they assume the two appearances in a same tumor. Among these tumors the so called protuberans fibrosarcomas, the sclerosing hemangiomas, many giant cell tumors, and the fibrous xanthomas must be considered as histiocytic tumors or fibrous histiocytomas. The malignant counterpart of fibrohistiocytomas, that is the malignant xanthofibroma, the malignant histiocytoma and the rare malignant protuberans fibrosarcoma, should be recognized.