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C A Reis

Publications and source records attributed to C A Reis.

At least 19 recordsLinked to original sources
PubMed2006

Different expression levels of alpha3/4 fucosyltransferases and Lewis determinants in ovarian carcinoma tissues and cell lines.

Ovarian carcinoma is the leading cause of death from gynecological cancers in many countries. Fucosylated glycoconjugates have been associated with various carcinomas. In the present study, we have characterized the expression of alpha3/4 fucosyltransferases transcripts and their products, the Lewis carbohydrate determinants, and their in vitro specificity towards synthetic acceptors using ovarian carcinoma cell lines OVM, m130, GG and SKOV3. We found different expression patterns: GG cells expressed mostly Lewisx (Lex), Lewisy (Ley), sLea and Leb, and m130 cells expressed mostly Lex and Ley. The detection was on the plasma membrane and in intracellular vesicles. OVM and SKOV3 cells had very low amounts of staining. From RT-PCR studies, enzyme specificity of cellular extracts towards a panel of synthetic carbohydrate acceptors and Western blot analysis we concluded that Lea, sLea and Leb were synthesised by FUT3, whereas Lex and Ley were synthesized by FUT4 and FUT9 in both cell lines. The GG and m130 cell lines are adequate models to investigate the role of Lex, Ley, sLea and Leb in ovarian carcinoma development.

Adenocarcinoma, Mucinous↗
PubMed2004

MUC5B expression in gastric carcinoma: relationship with clinico-pathological parameters and with expression of mucins MUC1, MUC2, MUC5AC and MUC6.

Previous studies have shown that mucin expression can be used to evaluate differentiation patterns of gastric carcinoma: MUC5AC expression is associated with diffuse type and early gastric carcinomas, and MUC2 expression is associated with mucinous gastric carcinomas. The role played by MUC5B in the evaluation of differentiation and biological behaviour of gastric carcinoma is largely unknown. Our aim was to characterise the pattern of expression of mucins MUC1, MUC2, MUC5AC, MUC5B and MUC6 in a series of 50 gastric carcinomas to evaluate whether MUC5B expression was associated with the clinico-pathological characteristics of the cases and/or with the co-expression of other mucins. A panel of six monoclonal antibodies (HMFG1, SM3, PMH1, CLH2, EU-MUC5Ba and CLH5) was used to determine the expression of mucins (MUC1, MUC1 underglycosylated form, MUC2, MUC5B, MUC5AC and MUC6, respectively) using immunohistochemistry. Cases were considered positive if more than 5% of the cells expressed immunoreactivity for the several mucins evaluated. Our results showed that: (a) expression of MUC5B was observed in 11 cases (22.0%) and was associated with the "unclassified" histological type of gastric carcinoma according to Laurén ( P = 0.03) and with the absence of venous invasion ( P = 0.02); (b) in this series, MUC5B expression had no impact on survival of patients with gastric carcinoma; (c) the expression of MUC5B was associated with the co-expression of MUC5AC ( P = 0.02) and (d) none of the cases with the so-called complete intestinal phenotype of mucin expression expressed MUC5B.

Antibodies, Monoclonal↗
PubMed2001

Chemoenzymatic synthesis of sialylated glycopeptides derived from mucins and T-cell stimulating peptides.

The Tn, T, sialyl-Tn, and 2,3-sialyl-T antigens are tumor-associated carbohydrate antigens expressed on mucins in epithelial cancers, such as those affecting the breast, ovary, stomach, and colon. Glycopeptides carrying these antigens are of interest for development of cancer vaccines and a short, chemoenzymatic strategy for their synthesis is reported. Building blocks corresponding to the Tn (GalNAc alpha-Ser/Thr) and T [Gal beta(1-->3)GalNAc alpha-Ser/Thr] antigens, which are relatively easy to obtain by chemical synthesis, were prepared and then used in the synthesis of glycopeptides on the solid phase. Introduction of sialic acid to give the sialyl-Tn [Neu5Ac alpha(2-->6)GalNAc alpha-Ser/Thr] and 2,3-sialyl-T [Neu5Ac alpha(2-->3)Gal beta(1-->3)GalNAc alpha-Ser/Thr] antigens is difficult when performed chemically at the building block level. Sialylation was therefore carried out with recombinant sialyltransferases in solution after cleavage of the Tn and T glycopeptides from the solid phase. In the same manner, the core 2 trisaccharide [Gal beta 1-->3(GlcNAc beta 1-->6)GalNAc] was incorporated in glycopeptides containing the T antigen by using a recombinant N-acetylglucosaminyltransferase. The outlined chemoenzymatic approach was applied to glycopeptides from the tandem repeat domain of the mucin MUC1, as well as to neoglycosylated derivatives of a T cell stimulating viral peptide.

Amino Acid Sequence↗
PubMed2001

Advantages of external accumulation for electron capture dissociation in Fourier transform mass spectrometry.

A combination of external accumulation (XA) with electron capture dissociation (ECD) improves the electron capture efficiency, shortens the analysis time, and allows for rapid integration of multiple scans in Fourier transform mass spectrometry. This improves the signal-to-noise ratio and increases the number of detected products, including structurally important MS3 fragments. With XA-ECD, the range of the labile species amenable to ECD is significantly extended. Examples include the first-time determination of the positions of six GalNAc groups in a 60-residue peptide, five sialic acid and six O-linked GalNAc groups in a 25-residue peptide, and the sulfate group position in a 11-residue peptide. Even weakly bound supramolecular aggregates, including nonspecific peptide complexes, can be analyzed with XA-ECD. Preliminary results are reported on high-rate XA-ECD that uses an indirectly heated dispenser cathode as an electron source. This shortens the irradiation time to > or = 1 ms and increases the acquisition rate to 3 scans/s, an improvement by a factor of 10-100.

Adrenocorticotropic Hormone↗
PubMed2001

Expression and localization of immunoreactive-sialomucin complex (Muc4) in salivary glands.

Sialomucin Complex (SMC; Muc4) is a heterodimeric glycoprotein consisting of two subunits, the mucin component ASGP-1 and the transmembrane subunit ASGP-2. Northern blot and immunoblot analyses demonstrated the presence of SMC/Muc4 in submaxillary, sublingual and parotid salivary glands of the rat. Immunocytochemical staining of SMC using monoclonal antisera raised against ASGP-2 and glycosylated ASGP-1 on paraffin-embedded sections of parotid, submaxillary and sublingual tissues was performed to examine the localization of the mucin in the major rat salivary glands. Histological and immunocytochemical staining of cell markers showed that the salivary glands consisted of varying numbers of serous and mucous acini which are drained by ducts. Parotid glands were composed almost entirely of serous acini, sublingual glands were mainly mucous in composition and a mixture of serous and mucous acini were present in submaxillary glands. Since immunoreactive (ir)-SMC was specifically localized to the serous cells, staining was most abundant in parotid glands, intermediate levels in submaxillary glands and least in sublingual glands. Ir-SMC in sublingual glands was localized to caps of cells around mucous acini, known as serous demilunes, which are also present in submaxillary glands. Immunocytochemical staining of SMC in human parotid glands was localized to epithelial cells of serous acini and ducts. However, the staining pattern of epithelial cells was heterogeneous, with ir-SMC present in some acinar and ductal epithelial cells but not in others. This report provides a map of normal ir-SMC/Muc4 distribution in parotid, submaxillary and sublingual glands which can be used for the study of SMC/Muc4 expression in salivary gland tumors.

Animals↗
PubMed2001

Evidence for glycosylation-dependent activities of polypeptide N-acetylgalactosaminyltransferases rGalNAc-T2 and -T4 on mucin glycopeptides.

We present evidence that site-specific O-glycosylation by recombinant polypeptide N-acetylgalactosaminyltransferases rGalNAc-T2 and -T4 is controlled by the primary sequence context, as well as by the position and structure of previously introduced O-glycans. Synthetic mucin-type (glyco)peptides corresponding to sections of the tandem repeat regions of MUC1, MUC2, and MUC4 were used as substrates for recombinant polypeptide N-acetylgalactosaminyltransferases, rGalNAc-T2 and -T4. By concerted and sequential action the two transferases are able to fully glycosylate MUC1 but only partially MUC2 and MUC4 tandem repeat peptides. GalNAc residues on MUC1 acceptor peptides trigger activity of rGalNAc-T4 directed to Ser in VTSA and Thr in PDTR and of rGalNAc-T2 to Ser/Thr within the GSTA motif of variant MUC1 peptides. However, elongation of GalNAc by beta3-galactosylation inhibits rGalNAc-T4 activity completely and rGalNAc-T2 activity with respect to the acceptor site GSTA. These findings are in accord with the inhibition of rGalNAc-T2 and -T4 by fully GalNAc-substituted MUC1 repeat peptide and support a glycosylation-dependent activity induction or enhancement of both enzymes.

Amino Acid Sequence↗
PubMed2001

Immunohistochemical study of the expression of MUC5AC and MUC6 in breast carcinomas and adjacent breast tissues.

AIM: To study the protein expression patterns of MUC5AC and MUC6 in normal and diseased breast tissues and to compare their expression with that of a mucin (MUC1) normally expressed in mammary tissues. METHODS: Formalin fixed, paraffin wax embedded tissue from 69 cases of invasive breast carcinoma and surrounding breast tissue was studied immunohistochemically with monoclonal antibodies against MUC1 (SM3), MUCSAC (CLH2), and MUC6 (CLH6), using the avidin-biotin-peroxidase method. RESULTS: MUC5AC was detected in five of 68 cases of invasive carcinoma including one of three cases of pure colloid carcinoma. MUCSAC expression in the adjacent normal breast epithelium was present in one of 29 cases and in one of two cases of ductal carcinoma in situ. None of 15 cases of ductal hyperplasia without atypia was positive for MUCSAC. MUC6 was present in 15 of 65 cases of invasive carcinoma, in four of 29 cases of normal adjacent epithelium, two of 15 cases of ductal hyperplasia without atypia, and one of two cases of ductal carcinoma in situ. MUC1 immunoreactivity detected by the SM3 antibody was present in 50 of the 67 cases of invasive carcinoma, but expression was also detected in benign epithelium. All invasive carcinomas expressing MUCSAC were positive for MUC1 and four were positive for MUC6. No significant association was found between the expression of these mucins and tumour size, histological grade, node status, oestrogen receptor status, p53 positivity, or c-ErbB-2 overexpression. CONCLUSIONS: This study documents the expression of two different mucins (MUCSAC and MUC6) not described as being expressed by normal breast tissues in a minority of breast carcinomas, as well as in normal and hyperplastic epithelium. Although the role of mucins in malignant transformation and the progression of breast cancer is not well understood, in some cases, there is probably an upregulation of several genes that encode distinct mucin proteins.

Adult↗
PubMed2000

The lectin domain of UDP-N-acetyl-D-galactosamine: polypeptide N-acetylgalactosaminyltransferase-T4 directs its glycopeptide specificities.

The initiation step of mucin-type O-glycosylation is controlled by a large family of homologous UDP-GalNAc:polypeptide N-acetylgalactosaminyltransferases (GalNAc-transferases). Differences in kinetic properties, substrate specificities, and expression patterns of these isoenzymes provide for differential regulation of O-glycan attachment sites and density. Recently, it has emerged that some GalNAc-transferase isoforms in vitro selectively function with partially GalNAc O-glycosylated acceptor peptides rather than with the corresponding unglycosylated peptides. O-Glycan attachment to selected sites, most notably two sites in the MUC1 tandem repeat, is entirely dependent on the glycosylation-dependent function of GalNAc-T4. Here we present data that a putative lectin domain found in the C terminus of GalNAc-T4 functions as a GalNAc lectin and confers its glycopeptide specificity. A single amino acid substitution in the lectin domain of a secreted form of GalNAc-T4 selectively blocked GalNAc-glycopeptide activity, while the general activity to peptides exerted by this enzyme was unaffected. Furthermore, the GalNAc-glycopeptide activity of wild-type secreted GalNAc-T4 was selectively inhibited by free GalNAc, while the activity with peptides was unaffected.

Amino Acid Sequence↗
PubMed2000

Reactivity of natural and induced human antibodies to MUC1 mucin with MUC1 peptides and n-acetylgalactosamine (GalNAc) peptides.

Antibodies (Abs) to MUC1 occur naturally in both healthy subjects and cancer patients and can be induced by MUC1 peptide vaccination. We compared the specificity of natural and induced MUC1 Abs with the objective of defining an effective MUC1 vaccine for active immunotherapy of adenocarcinoma patients. Serum samples, selected out of a screened population of 492 subjects for their high levels of IgG and/or IgM MUC1 Abs, were obtained from 55 control subjects and from 26 breast cancer patients before primary treatment, as well as from 19 breast cancer patients immunized with MUC1 peptides coupled to keyhole limpet hemocyanin (KLH) and mixed with QS-21. The samples were tested with enzyme-linked immunoassays for reactivity with (1) overlapping hepta- and 20-mer peptides spanning the MUC1 tandem repeat sequence; (2) two modified 60-mer peptides with substitutions in the PDTR (PDTA) or in the STAPPA (STAAAA) sequence of each tandem repeat; and (3) four 60-mer glycopeptides with each 1, 2, 3 and 5 mol N-acetylgalactosamine (GalNAc) per repeat. More than one minimal epitopic sequence could be defined, indicating that Abs directed to more than one region of the MUC1 peptide core can coexist in one and the same subject. The most frequent minimal epitopic sequence of natural MUC1 IgG and IgM Abs was RPAPGS, followed by PPAHGVT and PDTRP. MUC1 peptide vaccination induced high titers of IgM and IgG Abs predominantly directed, respectively, to the PDTRPAP and the STAPPAHGV sequences of the tandem repeat. Natural MUC1 Abs from breast cancer patients reacted more strongly with the N-acetylgalactosamine (GalNAc) peptides than with the naked 60-mer peptide, while reactivity with the GalNAc-peptides was significantly reduced (2-tailed p < 0.0001) in the MUC1 IgG and IgM Abs induced by MUC1 peptide vaccination. Whereas in cancer patients glycans appear to participate in epitope conformation, the epitope(s) recognized by MUC1 Abs induced by peptide vaccination are already masked by minimal glycosylation. Therefore, our results indicate that a MUC1 glycopeptide would be a better vaccine than a naked peptide.

Acetylgalactosamine↗
PubMed2000

Gastric carcinoma exhibits distinct types of cell differentiation: an immunohistochemical study of trefoil peptides (TFF1 and TFF2) and mucins (MUC1, MUC2, MUC5AC, and MUC6).

The expression of trefoil peptides (TFF1 and TFF2) and mucins (MUC1, MUC2, MUC5AC, and MUC6) has previously been described in gastric polyps. In the present study, the expression profile of these trefoil peptides and mucins was characterized in 96 gastric carcinomas, in an attempt to further the understanding of the histogenesis and cell differentiation of gastric carcinoma. Taking together the co-expression of trefoil peptides and mucins, three phenotypes were defined: complete gastric, incomplete gastric, and non-gastric phenotype. Gastric differentiation (complete and incomplete) was observed in 30 out of 33 (90.9%) diffuse carcinomas and in 38 out of 53 (71.7%) intestinal carcinomas. Non-gastric differentiation was observed in only three (9.1%) diffuse carcinomas and in 15 (28.3%) intestinal carcinomas. The phenotypes observed in intestinal carcinomas were similar to those previously observed in adenomatous polyps, whereas most diffuse carcinomas mimicked the phenotype of hyperplastic polyps. The percentage of cases displaying a non-gastric phenotype was higher, though not significantly, in tumours that had invaded the gastric wall than in T1 tumours, regardless of histotype. It is concluded that gastric-type differentiation is retained in the majority of gastric carcinomas, being more prominent in diffuse than in intestinal carcinomas, and in early than in advanced carcinomas.

Adenomatous Polyps↗
PubMed2000

Role of fucosyltransferases in the association between apomucin and Lewis antigen expression in normal and malignant gastric epithelium.

BACKGROUND: In normal gastric epithelium, MUC5AC is detected in superficial epithelium associated with Lewis type 1 antigens and MUC6 is detected in antral glands with Lewis type 2. Therefore, the stomach constitutes an excellent model to examine the role of glycosyltransferases in determining the specificity of apomucin glycosylation. AIMS: To determine the molecular basis of this association and to examine changes in expression of gastric and intestinal apomucins and their association with Lewis antigens during the gastric carcinogenesis process. METHODS: Fucosyltransferase (FUT1, FUT2, FUT3) and mucin (MUC5AC, MUC6) transcripts were detected using reverse transcription-polymerase chain reaction. Apomucin (MUC2, MUC4, MUC5AC, MUC6) and Lewis antigen (types 1 and 2) expression were analysed using single and double immunohistochemistry and in situ hybridisation. RESULTS: In the normal stomach, FUT1 is exclusively detected associated with MUC6; FUT2 is only detected when MUC5AC is present. This co-regulation is lost in gastric tumours, as is differential expression of MUC5AC and MUC6 in normal gastric epithelial cells. In gastric tumours, especially those with the intestinal phenotype, MUC2 and MUC4 genes are upregulated, and gastric-type and intestinal-type mucins are coexpressed. These changes are early events in the gastric carcinogenesis process, as they are detected in intestinal metaplasia. CONCLUSIONS: The glycosylation pattern found in normal gastric epithelium is dictated by the specific set of fucosyltranferases expressed by the cells rather than by the apomucin sequence. The development of intestinal metaplasia and gastric cancer is associated with the appearance of cellular phenotypes that are absent from normal epithelium.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed2000

Immunohistochemical study of the expression of MUC6 mucin and co-expression of other secreted mucins (MUC5AC and MUC2) in human gastric carcinomas.

To investigate the expression of MUC6 mucin in gastric carcinomas, we generated a novel monoclonal antibody (MAb CLH5) using an MUC6 synthetic peptide. MAb CLH5 reacted exclusively with the MUC6 peptide and with native and deglycosylated mucin extracts from gastric tissues. MAb CLH5 immunoreactivity was observed in normal gastric mucosa restricted to pyloric glands of the antrum and mucopeptic cells of the neck zone of the body region. In a series of 104 gastric carcinomas, 31 (29.8%) were immunoreactive for MUC6. The expression of MUC6 was not associated with histomorphological type or with clinicopathological features of the carcinomas. Analysis of the co-expression of MUC6 with other secreted mucins (MUC5AC and MUC2) in 20 gastric carcinomas revealed that different mucin core proteins are co-expressed in 55% of the cases. MUC6 was co-expressed and co-localized with MUC5AC in 45% and with MUC2 in 5% of the cases. Expression of MUC2 alone was observed in 25% of the cases. All carcinomas expressing MUC2 mucin in more than 50% of the cells were of the mucinous type according to the WHO classification. The co-expression of mucins was independent of the histomorphological type and stage of the tumors. In conclusion, we observed, using a novel well-characterized MAb, that MUC6 is a good marker of mucopeptic cell differentiation and is expressed in 30% of gastric carcinomas, independent of the clinicopathological features of the cases. Furthermore, we found that co-expression and co-localization of mucins in gastric carcinomas is independent of histomorphology and staging. Finally, we observed that intestinal mucin MUC2 is expressed as the most prominent mucin of the mucins tested in mucinous-type gastric carcinomas.

Animals↗
PubMed1999

Intestinal metaplasia of human stomach displays distinct patterns of mucin (MUC1, MUC2, MUC5AC, and MUC6) expression.

Intestinal metaplasia is a well-established premalignant condition of the stomach that is characterized by mucin carbohydrate modifications defined by histochemical methods. The purpose of the present study was to see whether the expression of mucin core proteins was modified in the different types of intestinal metaplasia and to evaluate the putative usefulness of mucins as "molecular markers" in this setting. We used a panel of monoclonal antibodies with well-defined specificities to MUC1, MUC2, MUC5AC, and MUC6 to characterize the expression pattern of mucins. In contrast to normal gastric mucosa, the complete form or type I intestinal metaplasia (n = 20) displayed little or no expression of MUC1, MUC5AC, or MUC6 in the metaplastic cells and strong expression of the intestinal mucin MUC2 in the goblet cells of all cases. The incomplete forms of intestinal metaplasia, type II (n = 25) and type III (n = 16), expressed MUC1 and MUC5AC in every case, both in goblet and in columnar cells. MUC6 was also expressed in 16 cases of type II intestinal metaplasia and in 11 cases of type III intestinal metaplasia. The intestinal mucin MUC2 was expressed in every case of incomplete intestinal metaplasia, mostly in goblet cells. The mucin expression profile in the different types of intestinal metaplasia allows the identification of two patterns: one defined by decreased levels of expression of "gastric" mucins (MUC1, MUC5AC, and MUC6) and expression of MUC2 intestinal mucin, which corresponds to type I intestinal metaplasia, and the other defined by coexpression of "gastric mucins" (MUC1, MUC5AC, and MUC6) together with the MUC2 mucin, encompassing types II and III intestinal metaplasia. Our results challenge the classical sequential pathway of intestinal metaplasia (from type I to type III via a type II intermediate step).

Antibodies, Monoclonal↗
PubMed1999

Patterns of expression of trefoil peptides and mucins in gastric polyps with and without malignant transformation.

The expression of two trefoil peptides (TFF1 and TFF2) and four mucins (MUC1, MUC2, MUC5AC, and MUC6) was evaluated by immunohistochemistry and reverse transcription-polymerase chain reaction (RT-PCR) in 29 gastric polyps, 10 hyperplastic and 19 adenomatous, eight of which displayed malignant transformation. The aims of this study were to characterize the expression profile of these molecules in each type of polyp and to investigate possible modifications of the profile during the process of malignant transformation. All hyperplastic polyps displayed immunoreactivity for TFF1, MUC5AC, and MUC1 in more than 75 per cent of the cells. In adenomatous polyps, three main phenotypes could be identified: complete gastric phenotype (co-expression of TFF1 and MUC5AC)-nine cases (47.4 per cent); incomplete gastric phenotype (TFF1-positive and MUC5AC-negative)-seven cases (36.8 per cent); non-gastric (intestinal) phenotype (no expression of TFF1 or MUC5AC)-three cases (15.8 per cent). Data yielded by immunohistochemistry and RT-PCR showed a good correlation for both TFF1 and TFF2. One hyperplastic and seven adenomatous polyps with villous architecture displayed foci of diffuse and intestinal-type carcinoma, respectively; in all of these cases, MUC1 expression and signs of gastric differentiation were observed in both the non-malignant and the carcinomatous component. It is concluded that gastric differentiation is a feature of hyperplastic polyps and of a subset of adenomatous polyps which is shared by early carcinomas arising in some of these polyps, regardless of the histological type of polyp and of carcinoma.

Adenomatous Polyps↗
PubMed1999

Mucins and mucin-associated carbohydrate antigens expression in gastric carcinoma cell lines.

Mucins are high-molecular-mass glycoproteins with high carbohydrate content and marked heterogeneity both in the apoprotein and in the oligosaccharide side chains. Mucin genes are expressed in a regulated manner, namely in the human stomach. The first aim of the present study was to characterise the expression of mucins and mucin-associated carbohydrate antigens in seven gastric carcinoma cell lines, and to compare their expression profiles with those of normal gastric tissues and human gastric carcinomas. Secondly, we aimed to see whether or not there is an association between the expression of mucins and mucin-associated carbohydrate antigens. Our results show that mucin expression in gastric carcinoma cell lines: (a) follows in part the mucin expression profile of normal gastric mucosa and gastric carcinomas with wide expression of MUC1 and MUC5AC; (b) parallels the aberrant pattern of mucin expression observed in human gastric carcinomas with occasional expression of MUC2, MUC3, MUC4 and MUC5B; (c) does not include, at least in our series, the expression of MUC6 mucin; and (d) follows in part the differentiation pattern of the carcinomas from which the cell lines originated, keeping S-Tn expression in cell lines derived from glandular carcinomas. Our results further demonstrate that there is no apparent relationship between the mucin core proteins and the simple mucin-type or Lewis carbohydrate antigens.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1998

Expression of fully and under-glycosylated forms of MUC1 mucin in gastric carcinoma.

The membrane-bound MUC1 mucin is expressed in normal mucosas and the aberrant expression of its under-glycosylated forms has been reported in carcinomas from different sites. Several studies have provided conflicting evidence regarding the relationship between MUC1 expression and outcome in cancer patients. In this study, we investigated the immunohistochemical expression of MUC1 epitopes, using 2 monoclonal antibodies (MAbs): HMFG1, which reacts with the fully glycosylated MUC1, was studied in 73 gastric carcinomas; and SM3, which recognises an under-glycosylated form of MUC1, was studied in 180 cases. HMFG1 stained the antrum foveolar cells and the body glands of normal gastric mucosa, whereas SM3 reactivity was restricted to the perinuclear region of some foveolar cells. Type I intestinal metaplasia exhibited down-regulation of MUC1 expression using both MAbs. Every gastric carcinoma was stained with HMFG1 and 80% with SM3. High levels of expression of HMFG1 were associated with lymphatic invasion, nodal metastatization, and advanced pTNM staging. The expression of SM3 was associated with the histologic (solid) type of carcinoma, expanding growth pattern, wall penetration, lymphatic invasion and age of the patients. Despite a trend for a poor outcome in patients with tumours (over)expressing MUC1 mucin, the survival of the patients evaluated by univariate and multivariate analysis was not significantly associated with the levels of expression of HMFG1 or with the expression of the SM3 epitope. We conclude that (a) MUC1 expression, namely of the SM3 cancer-associated epitope, is significantly associated with several aspects of gastric cancer development and progression; and (b) MUC1 expression should not be used as a prognostic marker in patients with gastric carcinoma.

Adult↗