Expression of sialyl-Tn, Tn and T antigens in primary liver cancer

Sialyl-Tn, Tn and T antigens are caused by aberrant or incomplete glycosylation of apomucins and are related to the aggressiveness of malignant neoplasms. Using 41 liver samples from patients with cholangiocarcinoma (including four with cirrhosis), 21 with combined hepatocellular-cholangiocellular carcinoma and 17 with hepatocellular carcinoma, the expression of sialyl-Tn, Tn and T antigens were characterized immunohistochemically and the correlation with apomucin profiles was evaluated. The prevalence of sialyl-Tn, Tn and T antigens expression was 89, 95 and 51% in cholangiocarcinoma without cirrhosis; 25, 75, and 0% in cholangiocarcinoma with cirrhosis; 29, 90, and 48% in combined hepatocellular-cholangiocellular carcinoma; and 0, 12 and 6% in hepatocellular carcinoma, respectively. Sialyl-Tn antigen was frequently expressed in cholangiocarcinoma without cirrhosis compared with cholangiocarcinoma with cirrhosis and combined hepatocellular-cholangiocellular carcinoma (P < 0.01). Although sialyl-Tn expression was associated with MUC1, MUC6 and MUC7 expression, the expression sites among them were not identical in the individual cases. These data suggest that the different expressions of sialyl-Tn antigen among cholangiocarcinoma without cirrhosis, cholangiocarcinoma with cirrhosis and combined hepatocellular-cholangiocellular carcinoma may reflect the biological features inherent to these tumors, such as the ability of invasion.     

Expression of Lewis X-related antigens in adenocarcinomas of lung

Fifty primary lung adenocarcinomas were examined immunohistochemically using monoclonal antibodies to determine changes in the expression of N-acetyl-lactosamine (blood group type-2 chain), Le^x, Le^Y and sialyl Le^x-i. These antigens were expressed in 60%, 70%, 90% and 94% of carcinomas, respectively; in 8%, 12%, 56% and 86% of normal broncho-bronchiolar epithelium; and in 32%, 0%, 100% and 0% of normal alveolar epithelium. The greater the complexity of the antigenic structure, the greater the incidence of positive staining in the adenocarcinomas. Although the more complex antigens such as sialyl Le^x-i and Le^Y have also been demonstrated in the sera of lung cancer patients, they were not always cancer-selective in our immunohistochemical study. In contrast, the less complex antigens such as N-acetyl-lactosamine (type-2 chain) and Le^x seem to be cancer-selective, as they showed low positivity in normal lung tissue.     

Mucin antigens expression and Ki-67 labeling in breast cancer: The peculiarity in scirrhous carcinoma

The expression of mucin-related antigens (Tn, T, Sialosyl-Tn [STn], DF3 [mammary-type apomucin related antigen], and intestinal-MRP [intestinal-type apomucin related antigen]) as well as Ki-67 labeling was examined in 58 mammary invasive ductal carcinomas (IDC) divided into 26 scirrhous subtype (SC) and 32 non-scirrhous subtype comprising papillotubular carcinoma and solid-tubular carcinoma (PT-ST). These data were analyzed in connection with the various pathological prognostic factors such as nodal status, tumor size, estrogen receptor status and histological grading of carcinomas. The results were as follows: (a) in SC, the expression rate of Tn was significantly higher in the cases with positive lymph node metastasis or with large tumor size (>2cm) than in those with negative lymph node metastasis or with small tumor size (>2 cm); (b) in PT-ST, the expression rate of STn was higher in the cases with positive lymph node metastasis or with large tumor size than in those with negative lymph node metastasis or with small tumor size; (c) in SC, Ki-67 labeling was significantly higher in the cases with positive lymph node metastasis than in those with negative lymph node metastasis; and (d) in PT-ST, Ki-67 labeling was lower in the cases with positive lymph node metastasis than in those with negative lymph node metastasis. In conclusion, Tn antigen expression was correlated with pathological prognostic factors in SC but not in PT-ST, whereas STn antigen expression was correlated with pathological prognostic factors in PT-ST but not in SC. Moreover, lnverse relationship between Ki-67 labeling and nodal status was observed in PT-ST. These differences between SC and PT-ST may be related to their different biological behaviors.     

The immunoexpression of Tn, sialyl-Tn and T antigens in chronic active gastritis in relation to Helicobacter pylori infection

The simple mucin-type carbohydrate antigens Tn, sialyl-Tn and T represent the mucin core oligosaccharide structures that are produced in the initial steps of mucin biosynthetic pathway. Utilising monoclonal antibodies anti-Tn antigen, anti-sialyl-Tn antigen and anti-T antigen, we have investigated the expression of the simple mucin-type carbohydrate antigens in 47 biopsy specimens of antral mucosa with chronic active gastritis, 25 of which had Helicobacter pylori infection. The Tn immunoreactivity, localised at the supranuclear region of surface and glandular mucous cells, was observed in all samples, independently from H. pylori status. The sialyl-Tn antigen, mainly localised in the cytoplasm of glandular mucous cells and in goblet cells vacuoles, was seen in 56% of the cases with H. pylori infection and in 41% of the cases in the H. pylori-negative group. In addition, the T antigen was found in the cytoplasm of surface and glandular mucous cells in 16% of the H. pylori-positive group, whereas the percentage of positive cases was reduced to 5% in H. pylori-negative patients, with an exclusive localisation in the cytoplasm of glandular mucous cells; after neuraminidase treatment, the percentage of T antigen-positive cases was increased to 28% in H. pylori-positive cases and to 27% in negative cases. No significant relationships between H. pylori infection and Tn, sialyl-Tn or T antigen immunoexpression were encountered in our cases. Therefore, we maintain that the inflammatory infiltrate may itself play an important role in the expression of simple mucin-type carbohydrate antigens in chronic active antral gastritis.     

Expression of Tn and sialyl-Tn antigens in tumor tissues of the ovary.

The expression of sialyl-Tn and Tn antigens in various benign, borderline, and malignant ovarian tumors was examined immunohistochemically using newly developed antibodies specific for sialyl-Tn and Tn antigens. Sialyl-Tn antigen was detected in only one benign tumor, a mucinous adenoma that showed faint cytoplasmic staining in a few cells. However, sialyl-Tn was present in 5 of 12 serous borderline tumors, 10 of 19 mucinous borderline tumors, 10 of 13 serous adenocarcinomas, 15 of 16 mucinous adenocarcinomas, 14 of 15 endometrioid adenocarcinomas, and 7 of 7 clear cell carcinomas of the ovary. The antigen expression was observed throughout the cytoplasm of cancer cells and in the apical cytoplasm and luminal contents of some glands. The incidence and intensity of staining for sialyl-Tn antigen were higher in malignant tumors than in borderline tumors, but these results did not correlate with the histologic classification or differentiation. Coexpression of sialyl-Tn antigen and Tn antigen was observed in two serous adenocarcinomas, six mucinous borderline tumors, five mucinous adenocarcinomas, eight endometrioid, and seven clear cell carcinomas. In no case was Tn antigen expressed without concomitant sialyl-Tn antigen expression. Accumulation of sialyl-Tn antigen seems to be an early event of carcinogenesis of the ovary.     

T (Thomsen–Friedenreich) antigen and other simple mucin-type carbohydrate antigens in precursor lesions of gastric carcinoma

In a previous report we suggested that T antigen appeared to be associated with gastric carcinoma. To verify this hypothesis and characterize the pattern of expression of simple-mucin type carbohydrate antigens (Tn. sialyl-Tn and T before and after neuraminidase) in normal gastric mucosa and precursor lesions of gastric carcinoma, we studied the mucosa adjacent to 100 cases of gastric carcinoma, gastric biopsies of 60 dyspeptic patients, eight adenomatous polyps and eight hyperplastic polyps. The expression of the antigens was more related to the cell type and underlying lesions than to the coexistence of carcinoma. The most distinctive findings concerned intestinal metaplasia, dysplasia and hyperplastic lesions. In intestinal metaplasia, Tn was found mostly in columnar cells and sialyl-Tn in goblet cells. T was more prevalent in incomplete intestinal metaplasia than in complete. A high prevalence of sialyl-Tn expression and cell membrane immunoreactivity for T antigen, similar to those previously found in gastric carcinomas, were observed in three adenomatous polyps, one hyperplastic polyp, five cases of adenomatous dysplasia in the neighbourhood of intestinal carcinomas and four cases of marked foveolar hyperplasia, three of which were from the mucosa adjacent to diffuse carcinomas. We conclude that adenomatous and hyperplastic lesions share with gastric carcinomas features of aberrant glycosylation, namely the cell membrane expression of T antigen.     

Simple mucin-type carbohydrate antigens (T,sialosyl-T,Tn and sialosyl-Tn) in breast carcinogenesis

Immunohistochemical analysis of the expression of simple mucin-type carbohydrate antigens (Tn, sialyl-Tn and T) was performed in a series of 43 cases of intraductal hyperplasia without atypia, 9 cases of intraductal hyperplasia with atypia, 54 cases of ductal carcinoma in situ (DCIS) and 26 cases of invasive breast carcinoma. We also studied 36 cases of isolated breast normal epithelium, 20 cases of normal breast epithelium adjacent to neoplasms and 14 cases of apocrine metaplasia. All antigens were detected in different frequencies in normal, hyperplastic, metaplastic and neoplastic breast epithelium. Tn and sialyl-Tn are expressed more frequently in malignant than in benign breast epithelium; while Tn expression increases from normal to invasive carcinomas, sialyl-Tn increases until DCIS and drops in invasive carcinomas, suggesting that either there is a failure of a proportion of DCIS to progress to invasive carcinoma or loss of expression of sialyl-Tn when some carcinomas become invasive. The high frequency of Tn and sialyl-Tn expression in breast intraductal proliferations probably reflects incomplete glycosylation in these lesions, which is a well-known tumour-associated phenomenon and supports the assumption that such lesions are putative precursors of breast cancer. T antigen was expressed in all groups studied, but its prevalence differed significantly between normal and neoplastic epithelium. The expression of these antigens in epithelium adjacent to carcinomas is similar to that found in isolated normal breast epithelium, whereas apocrine metaplasia has a pattern of simple mucin-type glycosylation that is specific and distinct from that of the normal breast epithelium, with a high frequency of marked expression of Tn and sialyl-Tn. The similarity of the pattern of expression of simple mucin-type antigens in metaplasia and malignant neoplasia reduces the usefulness of these markers from a diagnostic standpoint.This work was supported in part by a grant (no. 201240/92) from the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Brazil     

Cell surface glycosylation patterns in psoriasis

Cell surface carbohydrates are excellent markers of cellular differentiation and maturation processes due to their great structural and antigenic diversity as well as their known biosynthetic precursor/product relationships. Using a panel of monoclonal antibodies with well-defined carbohydrate specificities we have studied the expression of biosynthetically related antigens in normal and psoriatic skin. Two "families" of carbohydrate structures were investigated. One series of structures based on N-acetyllactosamine chains (type 2 chain: N-acetyllactosamine and fucosylated derivates hereof of H, Lex, Ley and sialyl-Lex) and another based on the simple mucin type core structures (type 3 chain: Tn, T and sialylated derivates hereof as well as the fucosylated derivative, H). Previously we have found these carbohydrate structures define distinct cell layers in stratified squamous epithelia of mucosa of the cheek, esophagus and uterine cervix. In normal and uninvolved epidermis, N-acetyllactosamine and T carbohydrates were found in the spinous cell layer, whereas the fucosylated derivates, H structures, were found in the granular cell layers above. The fucosylated and sialylated derivate of N-acetyllactosamine, sialylated Lex, had the same distribution as N-acetyllactosamine and T structures. This sequential expression of carbohydrates is similar to our previous findings in mucosa. However, in contrast to mucosa, normal skin basal cells did not label. The glycosylation pattern in psoriatic epithelium was changed in two ways. 1) Some carbohydrates (types 2 and 3 chain H and T) were expressed at an earlier stage of cell maturation. 2) The biosynthetic precursors to T structures, Tn and sialyl-Tn, which are not expressed in normal skin, and are often considered cancer-associated antigens, appeared in psoriatic skin. The Tn-antigen was expressed on basal and lower spinous cells, whereas the sialyl-Tn was only found on basal cells above the dermal papillae. The findings in the present work support previous studies of changes in cell surface glycosylation in psoriatic epidermis and demonstrate the appearance of tumor-associated antigens in highly proliferative, but benign, stratified epithelium.     

Differences in the O-glycosylation patterns between lung squamous cell carcinoma and adenocarcinoma

Mucins are highly O-glycosylated proteins synthesized by epithelial cells, and their glycosylation patterns can be altered during neoplastic transformation. The 2 types of non-small cell lung cancer (NSCLC) display a similar pattern of mucin gene expression but different reactivity to periodic acid-Schiff diastase, suggesting that a higher number of carbohydrate chains are present in adenocarcinomas. We compared the expression of core (Tn, sialyl-Tn, T) and terminal fucosylated and sialylated (Lewis antigens) carbohydrate structures in lung tumors. Specific antibodies were usedfor immunohistochemical and Western blot assays. Results indicated that core and terminal structures are detected more frequently in adenocarcinoma than in squamous cell carcinoma, except Lewis y, which is expressed strongly in both types of NSCLC. These data suggest that in squamous cell carcinoma and adenocarcinoma, different sets of glycosyltransferases must be expressed and that different posttranslational modifications of the mucin genes can take place in these 2 tumor types.     

Expression of native and deglycosylated colon cancer mucin antigens in normal and malignant epithelial tissues

Immunohistochemical techniques were used to determine the distribution and cellular location of the mature and precursor forms of a colonic-type mucin in normal and malignant epithelial tissues. The antisera used in this study were prepared against native human colon cancer mucin (LS), partially deglycosylated mucin (HFA or GalNAc-apomucin), and fully deglycosylated mucin (HFB or apomucin). These antisera reacted with most mucin-producing cells of the normal gastrointestinal tract, salivary ductular cells, bronchial epithelial cells, some bronchial mucous glands, and squamous epithelial cells of the esophagus. Breast, endometrium, ovary, prostate, liver, and thyroid were nonreactive. In most normal organs, HFB reactivity was present in the supranuclear and perinuclear cytoplasm and LS and HFA were located primarily in goblet cell vacuoles, apical cytoplasm, and luminal secretions. These findings are consistent with the expected subcellular locations of apomucin and more "mature" mucins. LS, HFA, and HFB were frequently expressed in adenocarcinomas of the colon, stomach, pancreas, and lung. Lymphoma, sarcoma, and melanoma specimens were nonreactive. Alterations in the expression of these mucin antigens in malignant tissues included loss of subcellular compartmentalization, increased intensity of staining, and disappearance of staining. In addition, de novo expression of HFB was observed in one of five breast carcinomas and three of five ovarian mucinous cystadenocarcinomas. These data demonstrate that LS, HFA, and HFB are useful for studying the organ specificities and biosynthetic pathways of one type of mucin in normal and malignant tissues.     

Simple mucin-type carbohydrate antigens (T, Tn and sialosyl-Tn) in mucoepidermoid carcinoma of the salivary glands

Thirty-two cases of mucoepidermoid carcinoma of the salivary glands were studied in order to characterize the expression of simple mucin-type carbohydrate antigens T, Tn and sialosyl-Tn and to evaluate its implication for tumour histogenesis. Monoclonal antibodies of known specificity were used on formalin-fixed, paraffin-embedded tissue, and the expression of these antigens was studied in each of the three cell types (mucous, intermediate and squamous) as well as in the secretory content of neoplastic lumina. Aberrant glycosylation of simple-mucin type antigens was found in all cell types, as compared with that of normal excretory duct cells of the salivary glands. The more 'primitive' antigens Tn and sialosyl-Tn were present in a high percentage of epidermoid and intermediate cells. Mucous cells and the intraluminal secretory content also expressed Tn in 57.7% of the cases. This contrasts with the absence of secretion of these simple mucin type carbohydrates by normal salivary gland cells. Mucin-producing cells did not express T antigen but only sialosyl-T, in contrast to 57.1% and 56.3% respectively of the epidermoid and intermediate cell types. T and sialosyl-T were also found in the secretory products of the neoplastic lumina in 11.5% and 53.6% of the cases, respectively. The distinctive glycosylation pattern between mucin-producing cells on the one hand and intermediate and squamous cells on the other does not contradict the common origin of the three cell types from the reserve cell of the salivary excretory duct, but favours the proposition that intermediate cells constitute a step in the differentiation pathway of epidermoid, but not of mucin-producing. cells.     

Expression of cancer/testis (CT) antigens in squamous cell carcinoma of the head and neck: Evaluation as markers of squamous dysplasia

Cancer/testis (CT) antigens, normally only expressed in germ cells of adult testis, can be activated in malignancy as tumor-specific antigens. The potential value of CT antigens as biomarkers in the evaluation of mucosal squamous precursor lesions of the head and neck has not been investigated. The expression of 8 CT antigens (MAGE-A, GAGE, NY-ESO-1, CT7, CT10, SAGE1, CT45 and NXF2) in 76 cases of invasive head and neck squamous cell carcinoma (SCC) was evaluated immunohistochemically. 65 mucosal biopsies of squamous dysplasia and 55 squamous papillomas with dysplasia were analyzed for 6 CT antigens, using an antibody cocktail. Of invasive SCC, 66% (50/76) expressed at least one CT antigen, most commonly MAGE-A (47%). Among the biopsies, only 1 of 55 squamous papillomas was CT-positive, whereas 8 of 65 (12%) squamous dysplasia lesions were CT-positive. These 8 CT-positive biopsies were from 6 patients, 3 of which had concurrent or subsequent SCC. CT antigens are frequently expressed in head and neck SCC; however, there was no difference in the clinicopathological characteristics or behavior of CT-positive tumors compared to CT-negative tumors. The usefulness of CT antigens as positive predictors for SCC in squamous dysplasia biopsies remains to be determined by long-term follow-up in larger cohorts.     

Expression of apoptosis, proliferating cell nuclear antigen, and apoptosis-related antigens (bcl-2, c-myc, Fas, Lewis and p53) in human cholangiocarcinomas and hepatocellular carcinomas

In situ expression of apoptosis and its related antigens has rarely been evaluated in human liver tumors. Therefore, Investigation using in situ nick end-labelling and Immunohistochemical methods of the in situ expression of apoptosis, prollferating cells, and apoptosis-related antigens in 7 normal livers, 20 cholanglocarclnomas (CC) and 17 hepatocellular carclnomas (HCC) was done. Apoptotlc cells as determined by the nick end-labelling method and proliferating cell nuclear antigen-positive cells were present in all specimens, and the percentage of them was significantly higher in CC than In HCC. Bcl-2 protein was present only in one CC e+nd one HCC, but was occasionally noted in bile ducts in non-cancerous livers. C-myc and Fas antigens were not found in any of the cases. Lewis^y antigen was expressed In 8 CC, but was absent in the other cases although bile ducts In non-cancerous livers frequently expressed Lewis^y. p53 protein was present in 8 CC, but was absent in the other cases. Serial section observation showed that apoptotic cancer cells ware consistently negative for proliferating cell nuclear antigen; bcl-2-positive cells did not show apoptosis; p53-positive cancer cells showed apoptosis. Some Lewis^y positive cancer cells showed apoptosis, while others did not. These data suggest that apoptosis and cell proliferation are lnvolved in CC and HCC, and their degree is more severe in CC than In HCC. p53 protein (stimulative) may regulate apoptosis in some cases, whereas c-myc, Fas and Lewis^y are not relatad to apoptosb In CC and HCC in vivo . Many other factors may regulate apoptosis in CC and HCC in vivo .     

Detection of Tn, sialosyl-Tn and T antigens in hereditary nonpolyposis colorectal cancer

The simple mucin-type carbohydrate antigens Tn, sialosyl-Tn, T and the cryptic sialylated variant of the last represent the mucin core oligosaccharide structures that are produced in the initial steps of the mucin biosynthetic pathway. Utilizing monoclonal antibodies anti-Tn antigen (HB-Tn1), anti-sialosyl-Tn antigen (HB-STn1), anti-T antigen (HB-T1) and the biotinylated Amaranthus caudatus agglutinin (ACA), we have investigated the expression of the simple mucin-type carbohydrate antigens in hereditary nonpolyposis colorectal cancer (HNPCC; 15 cases) compared with sporadic colorectal cancer (CRC; 60 cases) and normal colonic mucosa (30 cases). A variable positivity of Tn, sialosyl-Tn, T and the cryptic sialylated form of this latter antigen was encountered in both HNPCC and sporadic CRC cases; in addition, in normal colonic mucosa a constant reactivity was encountered only for Tn and the cryptic sialylated form of T, while negative results were always obtained for sialosyl-Tn and T antigens. Statistical analysis, performed using a Chi-square test, showed significantly lower (P=0.037) expression of sialosyl-Tn and higher (P=0.022) expression of T in HNPCC than in sporadic CRC, suggesting a greater presence of 1,3 galactosyl-transferase activity in HNPCC than in sporadic CRC. We were unable to identify a peculiar phenotype for HNPCC with simultaneous evaluation of reactivity for HB-Tn1, HB-STn1, HB-T1 and ACA; the biological significance of the preferential expression of T antigen in HNPCC remains to be investigated.     

Correlation between the number of apoptotic cells and expression of the apoptosis-related antigens Fas, Ley and bcl-2 protein in non-Hodgkin's lymphomas

The relationship between the number of apoptotic cells and the expression of apoptosis-related antigens was examined In 56 cases of non-Hodgkin's lymphomas and in 10 cases of reactive hyperplastic lymph nodes (RHL). Apoptosis was visually quantified by the in situ end-labeling (ISEL) method, and the expression of Fas, Le^y antigens and bcl-2 protein was examined by Immunohistochemistry. The expression of Le^y antigen was observed in germinal centers of RHL and 45% of non-Hodgkin's lymphomas. The apoptotic cell count (AC) in follicular lymphomas was significantly less than that in diffuse lymphomas. The distribution pattern of apoptotic cells In follicular lymphomas was inverse to that in RHL. In follicular lymphomas, AC was lower in follicles than in inter-follicular areas. In contrast, AC was higher in follicles than in Interfollicular areas in RHL. Le^y antigen-positive lymphomas showed a significantly higher AC than the negative cases. The Fas antigen-positive lymphomas showed a higher AC than the negative cases. However, AC in bcl-2 protein-positive and negative cases was not significantly different. These results suggest that Le^y and Fas antigens appear to be involved in the apoptotic tendency of tumor cells in non-Hodgkin's lymphomas, whereas bcl-2 does not necessarily.     

Pathological study of carbohydrate antigens in human lung cancer with monoclonal antibodies]

The expressions of carbohydrate antigens were examined with panel of specific anti-carbohydrate monoclonal antibodies (MAbs) on human lung cancer tissues. The MAbs used were SH1, SH2, SNH3, AH6, CA3F4, TKH2, TKH6 and TKH5 which define Lex, dimeric Lex, sialosyl Lex, Ley, Lea, sialosyl Tn, Tn and fucosyl GM1, respectively. Paraffin-embedded tissue sections (30 squamous cell carcinomas, 30 adenocarcinomas and 27 small cell carcinomas) were tested by immunohistological staining. Evaluation of stained specimens was performed by taking mean value of scores evaluated by three independent examiners. In squamous cell carcinoma, expression of Ley, sialosyl Tn, sialosyl Lex and Lea was significantly higher than other antigens. Lex was also expressed especially in keratinized tissues. In adenocarcinoma, Lea was expressed most remarkably. Sialosyl Lex, Ley, sialosyl Tn were also highly expressed in malignant cells. There was no significant difference in staining patterns between well and poorly differentiated adenocarcinomas. Sialosyl Tn and sialosyl Lex were positive in morphologically normal mucous glands adjacent to tumors. In small cell carcinomas, Ley was expressed more than other types of tumors, whereas Lex and sialosyl Tn were less than others. Tn antigen was observed throughout adenocarcinomas, squamous and small cell carcinomas in a relatively weak manner. Dimeric Lex and fucosyl GM1 antigens were not detected. Most of normal lung sections showed negative staining with those MAbs. These findings indicate that there are differential expressions of certain carbohydrate antigens in different types of human lung cancers based on their origins.     

Simple mucin-type carbohydrate antigens (Tn, sialosyl-Tn, T and sialosyl-T) and gp 230 mucin-like glycoprotein are candidate markers for neoplastic transformation of the human cervix

Mucins and simple mucin-type carbohydrates are cancer-associated antigens in several human tumors. Expression of Tn, sialosyl-Tn, Thomsen-Friedenreich (T), sialosyl-T and of a recently identified mucin-like glycoprotein (gp230) has not yet been thoroughly investigated in human cervix carcinogenesis. In the present study sections from normal cervix (n=10), CIN III lesions (n=10), and invasive carcinomas (n=47) were evaluated immunohistochemically using monoclonal antibodies. In normal cervix there was: cytoplasmatic expression of Tn in 1 case (10%); membranous expression of STn in 8 cases (80%); no expression of T and cytoplasmatic expression of ST in 1 case (10%); gp 230 was expressed in all cases with a membranous pattern. In CIN III lesions there was cytoplasmatic and membranous expression of Tn in 3 cases (30%) and of STn in 9 cases (90%); T and ST were not expressed; gp 230 was expressed in 5 cases (50%) both in the cytoplasm and at the cell membrane. In invasive carcinomas we observed Tn expression in 30 cases (63.8%) and STn in 31 cases (66%); T antigen was not expressed; expression of both ST and gp 230 in 24 cases (51.1%); all antigens showed membranous and cytoplasmatic staining. Our results show that Tn and ST are good markers of invasive carcinomas of the human cervix. We have also shown that loss of expression of the mucin-like glycoprotein gp 230 is associated with malignant transformation at a preinvasive stage. Received: 16 December 1999 / Accepted: 9 February 2000     

Expression of MUC1 and MUC2 and carbohydrate antigen Tn change during malignant transformation of biliary papillomatosis

AIM: Biliary papillomatosis is characterized by papillary proliferations of biliary lining cells without invasion or metastasis. The neoplastic character and biological behaviour of this disease remain still speculative. These issues were examined in this study. METHODS AND RESULTS: Mucin core protein MUC1, MUC2, MUC3, MUC5AC and carbohydrate antigens (T, Tn and sialosyl Tn) were immunohistochemically examined, using 11 lesions of biliary papillomatosis from seven patients, and five lesions of biliary papillomatosis with foci of carcinoma from four patients. Five cases of papillary intrahepatic cholangiocarcinoma and 12 histologically normal livers were used as a control. Patients with biliary papillomatosis alone or with carcinoma were middle-aged or elderly (five men and six women). Microscopically, biliary papillomatosis showed a villous, papillo-tubular, papillary, or papillo-villous pattern with a thin fibrovascular core. Cytologically, they were classifiable into biliary epithelial or pyloric gland-like type. The former was frequent in the cases associated with carcinoma. Expression of MUC1, Tn antigen and sialosyl Tn antigen was frequent and marked in biliary papillomatosis alone and with carcinoma and also intrahepatic papillary carcinoma. In addition, marked expression of MUC1 and Tn antigen were rather frequent in biliary papillomatosis with carcinoma and intrahepatic biliary papillary carcinoma compared with biliary papillomatosis. MUC2 was rather frequent and marked in biliary papillomatosis alone compared to other two disease groups. Focal expression of MUC5AC and MUC2 was rather frequent and infrequent irrespective of disease group, respectively. Focal expression of T antigen was frequent in papillary ICC. CONCLUSION: Biliary papillomatosis could undergo overt malignant transformation along with altered phenotypic expression of MUC proteins and mucin carbohydrate antigens.     

Expression patterns of type II pneumocyte apical surface glycoconjugates in lung adenocarcinoma cells

 Monoclonal antibodies and lectins were used to examine the expression patterns of apical membrane oligosaccharide sequences specific to type II pneumocytes in atypical adenomatous hyperplasia (AAH) and lung cancer. Atypical cells of AAH and papillary adenocarcinoma cells expressed abundant sialyl Thomsen-Friedenreich (TF) antigen: this was not observed in acinar adenocarcinoma, bronchioloalveolar carcinoma with mucin production or squamous cell carcinoma. Sialyl Tn antigens was also detected on a few cells in AAH and papillary adenocarcinomas. Asialo TF and Tn antigen were not observed on the surface of carcinoma cells of any type. Alpha(α)2,3-linked sialic acids predominated in type II pneumocyte, AAH and papillary adenocarcinoma, whereas ciliated columnar cells expressed α2,6-linked sialic acids. Lewis^x and sialyl Lewis^x antigens capped the TF antigen in both O- and N-linked side chains on the surface of AAH and papillary adenocarcinoma cells, but were not expressed by type II pneumocytes. The findings demonstrate that papillary adenocarcinoma cells resemble type II pneumocytes in that they express abundant sialyl TF surface antigen, but they also express TF-related antigens not found in type II pneumocytes. Apical surface glycoconjugates of AAH have structural characteristics shared by both type II pneumocytes and papillary adenocarcinoma cells. Received: 6 July 1998 / Accepted: 25 September 1998     

Differential expression of the cancer associated antigens T (Thomsen-Friedenreich) and Tn to the skin in primary and metastatic carcinomas.

AIM: To study the immunohistochemical expression of the Thomsen-Friedenreich antigen (T) and its precursor, Tn, in the skin in various cancers. METHODS: T and Tn antigens were studied with monoclonal antibodies in 91 primary premalignant and malignant lesions, 13 cases of Paget's disease, and 26 carcinomas metastatic to the skin. The material had been collected over a 10 year period, formalin fixed, and paraffin embedded. Diagnoses had been made after examination of standard histological sections, supplemented when needed by appropriate immunohistochemical staining. RESULTS: 21% and 29% of the primary cutaneous premalignant and malignant epithelial tumours expressed the Tn and T antigens, respectively. By contrast, 81% of metastatic carcinomas to the skin were Tn positive, while only 23% of them expressed the T antigen. All cases of Paget's disease were Tn positive but only 15% of them expressed the T antigen. The 21 nonepithelial tumours (including melanomas) were as a rule unreactive. CONCLUSIONS: The accumulation of the precursor (Tn) antigen in tumours metastasising to the skin highlights the incomplete glycosylation of carbohydrate antigens occurring in these tumours. The predominant Tn versus T antigen expression appears to be a useful immunohistochemical feature which may aid in the differentiation of primary cutaneous carcinomas from metastatic tumours.