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P L Devine

Publications and source records attributed to P L Devine.

At least 55 records · Page 3Linked to original sources

Factors effecting the measurement of tumor-associated MUC1 mucins in serum.

MUC1 epithelial mucins are produced by both normal and malignant epithelial cells. Serum proteins reactive with monoclonal antibodies against MUC1 mucins were studied using several techniques. Separation of proteins by native PAGE showed that anti-MUC1 core protein antibodies reacted with a high M(r) mucin but also with a 70-kD protein (p70) in normal women and women with ovarian cancer. After purification by gel filtration, p70 was not reactive in a double-determinant ELISA (CASA) and only weakly reactive in an inhibition assay. Serum CASA levels increased during pregnancy but p70 disappeared. Neuraminidase treatment of serum resulted in a greater increase in CASA in normal women and in ovarian cancer patients with low initial CASA than in ovarian cancer patients with high CASA and pregnant women (p < 0.05). These findings suggest that pregnancy and ovarian cancer-derived mucins are less heavily sialylated than mucin derived from normal tissues. An inhibition assay was developed which was more sensitive, but provided no diagnostic advantage over CASA. MUC1 is present in the serum of all women, reactivity in assays utilizing core protein antibodies is probably dependent not only on molar concentration but on the degree of exposure of peptide epitopes.

Chromatography, Gel↗

Serum markers CASA and CA 15-3 in ovarian cancer: all MUC1 assays are not the same.

The serum MUC1 markers CASA and CA 15-3 were compared with CA 125 in the serum of patients with ovarian cancer and in pregnant women. Used individually, CASA and CA 15-3 gave sensitivities of 54 and 56% in pre-operative ovarian carcinoma (n = 50), though these were lower than with CA 125 (84%). CASA levels were elevated in 3 women with a negative CA 125, while CA 15-3 was elevated in 2 of these women. The combined use of CA 125 with CASA or CA 15-3 led to the preclinical detection of recurrence in 4/5 patients, with mean lead times of 3.6 and 4.3 months, respectively. Of particular interest was the marked difference in reactivity observed with CASA and CA 15-3 in some patients, despite both assays utilising monoclonal antibodies (MAbs) that react with the MUC1 mucin. CA 15-3 and CASA showed a lower than expected correlation in patients with ovarian cancer (r = 0.70), with some patients having high concentrations of one mucin marker and low concentrations of another. Furthermore, different marker profiles were observed when monitoring the progress of patients with these markers. Marked differences between CA 15-3 and CASA were also observed in the serum of pregnant women (n = 10), where CASA showed marked elevation (mean 33.6 times cutpoint) and CA 15-3 did not (mean 0.88 times cutpoint). These data suggest that the specificities of the MAbs used in these assays affect the glycoform of MUC1 detected, and that it should not be assumed that all MUC1 assays will behave in the same manner.

Biomarkers, Tumor↗

Identification of two major populations of mucins in respiratory secretions.

Two populations of reduced subunits were present in the mucins purified from pooled normal secretions and asthmatic and chronic bronchitic sputa; their relative level differed between samples. To investigate the nature of this heterogeneity, an asthmatic respiratory mucin preparation from a single individual was reduced and alkylated with 14C-iodoacetamide. This preparation was analyzed by gel filtration, agarose gel electrophoresis, immunoblotting, rate-zonal- and density-gradient centrifugation, and HPLC ion-exchange- and reverse-phase chromatography. Two populations (A and B) of reduced mucin subunits and a high-M(r)protein-rich fraction were identified. Species A has the higher molecular mass, is slowest migrating on agarose electrophoresis, has longer oligosaccharide chains, and expresses the carbohydrate structure sialyl-Le(x). Species B has a lower molecular mass, migrates faster in agarose electrophoresis Species B has a lower molecular mass, migrates faster in agarose electrophoresis, has shorter chains, and does not express sialyl-Le(x). The two subunits have similar but not identical amino acid compositions and 14C-tryptic peptide maps indicating they have different protein cores. The anti-sialyl-Le(x) antibody selectively precipitated subunit A not only from the reduced but also from the nonreduced mucin preparation, demonstrating that subunits A and B are present in different intact mucins.

Amino Acids↗

Keratinocyte growth factor induces proliferation of hepatocytes and epithelial cells throughout the rat gastrointestinal tract.

Keratinocyte growth factor (KGF), a member of the fibroblast growth factor (FGF) family, was identified as a specific keratinocyte mitogen after isolation from a lung fibroblast line. Recently, recombinant (r)KGF was found to influence proliferation and differentiation patterns of multiple epithelial cell lineages within skin, lung, and the reproductive tract. In the present study, we designed experiments to identify additional target tissues, and focused on the rat gastrointestinal (GI) system, since a putative receptor, K-sam, was originally identified in a gastric carcinoma. Expression of KGF receptor and KGF mRNA was detected within the entire GI tract, suggesting the gut both synthesized and responded to KGF. Therefore, rKGF was administered to adult rats and was found to induce markedly increased proliferation of epithelial cells from the foregut to the colon, and of hepatocytes, one day after systemic treatment. Daily treatment resulted in the marked selective induction of mucin-producing cell lineages throughout the GI tract in a dose-dependent fashion. Other cell lineages were either unaffected (e.g., Paneth cells), or relatively decreased (e.g., parietal cells, enterocytes) in rKGF-treated rats. The direct effect of rKGF was confirmed by demonstrating markedly increased carcinoembryonic antigen production in a human colon carcinoma cell line, LIM1899. Serum levels of albumin were specifically and significantly elevated after daily treatment. These results demonstrate rKGF can induce epithelial cell activation throughout the GI tract and liver. Further, endogenous KGF may be a normal paracrine mediator of growth within the gut.

Animals↗

Serum mucin antigens CASA and MSA in tumors of the breast, ovary, lung, pancreas, bladder, colon, and prostate. A blind trial with 420 patients.

BACKGROUND: The tumor markers CASA (cancer-associated serum antigen) and MSA (mammary serum antigen) have previously been shown to be useful in the clinical management of ovarian and breast carcinoma, respectively, but have not been assessed in other types of cancer. These assays were compared with carcinoembryonic antigen (CEA) and prostate-specific antigen (PSA) in a blind trial using sera from the Mayo Clinic-National Cancer Institute (NCI) Diagnostic Serum Bank. METHODS: CASA and MSA were assessed retrospectively in a blind trial using 465 serum samples from the Mayo Clinic-NCI Diagnostic Serum Bank representing malignant and benign disease of the breast, ovary, lung, pancreas, bladder, colon, and prostate and age-matched and gender-matched healthy control donors. CASA, MSA, and PSA levels were determined using commercially available kits, and CEA values and clinical details were later provided by the Mayo Clinic. RESULTS: CASA and MSA showed good reproducibility in 45 duplicate samples. CASA values were significantly elevated in the serum of patients with malignant tumors of the breast (44%), ovary (58%), lung (56%), prostate (48%), and bladder (54%), but not in those with benign conditions of these organs or pancreatic or colon cancer. MSA levels were only elevated significantly in cancers of the breast (52%) and ovary (58%). CASA showed significantly better sensitivity than either CEA (20%) or MSA (25%) in the detection of lung cancer, whereas CEA showed significantly superior detection of colon cancers (78%). CASA was not as sensitive as PSA in prostate cancer (48% versus 96%), but gave superior specificity in nonmalignant conditions of the prostate (93% versus 70%), although this was not statistically significant. CONCLUSIONS: The commercial CASA and MSA assays are reliable and reproducible tests for these tumor markers. In addition to ovarian cancer, CASA is also elevated significantly in many patients with breast, lung, prostate, and bladder cancer and has potential clinical use in patients with these tumors. The use of the MSA assay appears restricted to breast cancer.

Aged↗

Circulating tumour-associated mucin concentrations, determined by the CASA assay, in healthy women.

This investigation was undertaken to establish a reference range for tumour-associated MUC1 mucins in the serum of healthy women of the ages at risk for adenocarcinoma of the ovary and breast. Blood samples and clinical information were obtained from 5,000 women attending a breast screening mammography clinic. Data from women diagnosed with breast carcinoma and those subsequently diagnosed with other cancers were omitted from the reference range. Mucin concentrations were measured using the CASA assay which detects the protein core of MUC1 encoded mucins. Multiple linear regression analysis showed no effect on CASA concentrations by non-malignant changes to the breast, menopausal status, presence/absence of the reproductive tract, parity or history of hormone use. However, CASA concentrations were significantly increased in smokers (P < 0.001) and progressively increased with age (P < 0.001). These data show that these factors must be given consideration when setting upper limits of normal using MUC1 protein core binding assays.

Age Factors↗

Monoclonal antibodies reacting with the MUC2 mucin core protein.

This study sought to produce monoclonal antibodies (MAbs) which reacted with the MUC2 core protein. Two MAbs [3A2 (IgG1) and 4F1 (IgM)] were produced by immunising female BALB/c mice with gel-formed mucin from the LS174T colon cancer cell line followed by a KLH conjugate of a 29 amino acid synthetic peptide whose sequence was derived from the variable number of tandem repeats (VNTR) region of a MUC2 cDNA clone. The MAbs reacted with synthetic MUC2 VNTR peptides but not synthetic MUC1 or MUC3 VNTR peptides, and showed specific reactivity in Western blotting with a high molecular weight protein produced by the LS174T colon carcinoma cell line. The use of shorter peptides indicated that the minimum peptide epitopes for these MAbs were different. Mab 3A2 reacted with amino acids 5-19 of the MUC2 VNTR by inhibition ELISA but not by direct ELISA, while 4F1 reacted with this peptide in both assays. Furthermore, 4F1 reacted in direct ELISA when a larger (29 amino acid) MUC2-derived peptide was coated onto the assay plate by incubating in carbonate buffer or by drying the peptide onto the assay plate, while 3A2 only reacted when this peptide was coated in carbonate buffer. The different specificity of the MAbs was also illustrated by the reactivity of 4F1 but not 3A2 with partially deglycosylated cystic fibrosis mucin. Immunohistochemical analysis with these MAbs revealed a strong reactivity with lung, gastric and colon tumours relative to normal tissue, with some breast and ovarian tumours also reacting. Both MAbs stained some normal goblet cells in the perinuclear region but not the mucin droplet or secreted mucin, indicating a reaction with immature (poorly glycosylated) mucin in the endoplasmic reticulum and/or golgi, but not with mature (fully glycosylated) mucin. In contrast, tumours showed strong diffuse cytoplasmic staining. 4F1 also showed weak apical cytoplasmic staining in some goblet cells and stained some tumours which showed no reactivity with 3A2. These antibodies should prove useful in the study of MUC2 structure and function, and in the diagnosis of some tumours.

Amino Acid Sequence↗

Peptide binding sites recognized by anti-mucin (MUC2) monoclonal antibodies.

Multiple genes coding for human mucins have been identified (MUC 1-5) and here monoclonal antibodies (MoAb) to a gastrointestinal mucin--MUC2 are examined. The antibodies were made to a synthetic peptide representing a single repeat in the core protein of the variable number of tandem repeat region. Using the six-mer overlapping peptides synthesized on polyethylene pins, different binding sites were detected by five anti-MUC 2 MoAbs. These contained amino acids: STTT, PTT, GTQTP, TPTP and PTTT (one antibody), and TPTPT. The repeat region of MUC2 essentially is hydrophobic, but contain useful immunogenic sites. This information will be useful for studying the structure and function of MUC2.

Amino Acid Sequence↗

Expression of MUC2 epithelial mucin in breast carcinoma.

AIMS: To examine the expression of the MUC2 epithelial mucin in breast carcinoma; to relate this to patient survival. METHODS: Sections from 210 breast carcinomas were stained with the anti-MUC2 core protein monoclonal antibody, 4F1, using an immunoperoxidase technique. The proportion of tumour cells positively stained and the localisation and intensity of any staining were recorded. Expression of MUC2 was compared with histological type and grade, tumour size, presence of nodal metastases, presence of oestrogen receptors, and menopausal status. The prognostic value of MUC2 expression was examined using Kaplan-Meier survival analysis. RESULTS: MUC2 mucin was detected in 19% of cases of invasive carcinoma, in 11% of cases of carcinoma in situ, where present, but very rarely in adjacent normal breast epithelium. Presence of MUC2 was significantly associated with a shorter disease free interval (p < 0.05), although the observed difference in duration of overall survival was not significant. CONCLUSIONS: The MUC2 detected in breast carcinoma may be underglycosylated or staining may represent detection of the protein core before the completion of glycosylation. The virtual absence of 4F1 reactivity in normal breast epithelium suggests that, unlike the MUC1 mucin, the MUC2 mucin is not highly expressed by these cells. The mechanism by which expression of MUC2 affects the biology of breast tumours is unclear, although expression may be a reflection of general derepression of genes during tumour progression.

Biomarkers, Tumor↗

The use of mucin-specific monoclonal antibodies and lectins in the detection of tumor-associated serum markers in gynecological cancer.

The use of the mucin-specific lectin from Sambucus sieboldiana (SSAM) in the detection of tumor-associated serum antigens produced by patients with ovarian, cervical, and uterine cancer was investigated. Two-site assays were developed which used either SSAM or the MUC1 core protein-specific monoclonal antibody (mab) BC2 as capture, and biotinylated SSAM to detect bound mucin (SSAM and BC2SSAM assays respectively). These new assays were compared to the CA125 assay, and another assay for MUC1 (CASA), which utilizes the core protein reactive mabs BC2 and BC3. some asymptomatic women and patients with benign disease showed very high levels in the SSAM assay, while this was not the case in the other assays. When cutoff levels were set to exclude healthy women and patients with benign disease, the levels of detection in patients with ovarian cancer were 51% with CASA (> 6.7 units/ml), 71% with CA125 (> 250 units/ml), and 38% with BC2SSAM (> 8.6 units/ml). The levels of detection in cervical and uterine cancer patients were 28% and 25% with CASA, 0% and 8% with CA125, and 28% and 25% with BC2SSAM respectively. Of particular interest was the very different spectrum of reactivity observed with the CASA and BC2SSAM assays which use the same capture mab, indicating that each assay detects different glycoforms of the MUC1 mucin. Indeed, when used in combination, the CASA and BC2SSAM assays gave 62% of ovarian cancer patients, and 50% of cervical or uterine cancer patients with elevated marker levels. The additional use of BC2SSAM gave no advantage over the combined use of the CASA and CA125 assays in ovarian cancer, with 80% of patients detected, but the CASA/BC2SSAM combination was particularly useful in the cervical and uterine cancers due to the low level of detection with CA125. In fact, the additional use of CA125 gave no advantage over the CASA/BC2SSAM combination in these patients. Furthermore, the BC2SSAM assay may also be useful in monitoring patients with high preoperative BC2SSAM levels (> 10 units/ml), since this assay predicted recurrence in 5/5 cases, and was negative in all cases with no evidence of disease. Furthermore, the performance of this assay in monitoring these patients was equal or superior to CA125 and CASA.

Antibodies, Monoclonal↗

Second-generation monoclonal antibodies to intestinal MUC2 peptide reactive with colon cancer.

BACKGROUND: Antitumor antibodies have traditionally been made to whole tumors or tumor extract. The use of defined synthetic antigens would be desirable for producing monoclonal antibodies. PURPOSE: Our purpose was to determine if antipeptide antibody to MUC2 had antitumor activity and specificity. METHODS: A 29-amino-acid peptide to MUC2 was synthesized and monoclonal antibodies were produced after immunizing BALB/c mice with peptide-keyhole-limpet hemocyanin in complete Freund's adjuvant, and the monoclonal antibodies were tested on peptides and human tissues. RESULTS: CCP31, CCP37, and CCP58 monoclonal antibodies were produced using MUC2 MI-29 (KYPTTTPISTTTMVTPTPTPTGTQTPTTT) containing one repeat unit of 23 amino acids and part of the next repeat of four amino acids. These antibodies reacted with the MUC2-derived peptide but not with MUC1- or MUC3-derived peptides. One of the monoclonal antibodies, CCP58, reacted strongly with human colon cancer and normal intestine in both fresh and formalin-fixed tissues; two other antibodies, CCP37 and CCP31, reacted only with fresh human tissues of normal colon and malignant colon tumors by immunoperoxidase staining. In addition, CCP37 and CCP58 reacted strongly with human gastric cancer; all antibodies reacted weakly with human salivary gland, and none reacted with tissues from normal human lung, kidney, stomach, pancreas, or endometrium. By analysis of mucin molecules by Western blotting, the antigen detected by monoclonal antibodies CCP37 and CCP58 was found to be of a high relative molecular mass (520 kd). CONCLUSIONS: Anti-MUC2 peptide antibodies appear to be relatively tissue specific and represent a new method of producing antitumor antibodies.

Amino Acid Sequence↗

Mucins: structure, function, and associations with malignancy.

Mucins are a family of high molecular weight, highly glycosylated glycoproteins found in the apical cell membrane of human epithelial cells from the mammary gland, salivary gland, digestive tract, respiratory tract, kidney, bladder, prostate, uterus and rete testis. Increased synthesis of the core protein and alterations in the carbohydrates attached to these glycoproteins are believed to play important roles in the function and proliferation of tumour cells. Aberrant glycosylation leads not only to the production of novel carbohydrate structures, but also to the exposure of the core peptide. These novel epitopes may be candidates for diagnosis or therapy, by using either synthetic mucin fragments as vaccines, or monoclonal antibody-based reagents which detect these structures.

Amino Acid Sequence↗

Expression of MUC1 and MUC2 mucins by human tumor cell lines.

The secretion and nature of mucins produced from a panel of recently available new gastric and colon carcinoma cell lines (LIM1839, LIM1215, LIM1863, LIM1899, LIM2099, LIM2405, LIM2408, LIM2412, LIM2463), as well as other colon (LS174T, HT29, HT29-SB, COLO533, COLO206), breast (T47D, MCF-7, BT20, ZR75-1) and ovarian (COLO316) tumor cell lines, was investigated. ELISA and Western blotting of the culture supernatants with novel anti-MUC1 and anti-MUC2 monoclonal antibodies (MAbs) specific for mucin core proteins showed their secretion by most of these cell lines. In addition, mucins produced by these cell lines expressed the tumor-associated carbohydrate detected by MAb 3E1.2 (glycolylsialyl-Tn, mammary serum antigen or MSA) and the Tn or T antigens reactive with lectin SSA-M. SSA-M detected MUC1 or MUC2 captured by MAbs BC2 or CCP58, while 3E1.2 only detected MUC1-associated carbohydrate, indicating that the MAb may react with a conformationally dependent epitope, or that the sialyl/glycolyl-transferases involved in MSA production may be sequence specific. In addition, the BC2/SSA-M and CCP58/SSA-M assays detected mucins in some samples which were not detected by BC2/BC2 or CCP58/CCP58 dual determinant assays, indicating that this format may be more appropriate for the detection of tumor-associated mucins in body fluids. These new cell lines and assays should be of use in the investigation of mucin core proteins, particularly LIM2463 and LIM1839 which express significant quantities of both MUC1 and MUC2.

Amino Acid Sequence↗

A sensitive microplate assay for glycoproteins that utilizes an immunological digoxigenin-based detection system.

A sensitive microplate assay for glycoproteins, based on an immunological digoxigenin-based detection system, is described. When log absorbance was plotted against log concentration, linear standard curves were obtained over the range 25 ng/ml to 25 microliters/ml with bovine submaxillary mucin, porcine stomach mucin, fetal calf fetuin, asialofetuin and human transferrin. This detection limit and range are far superior to other assays that have been described. The use of the microtiter plate format means that a large number of samples can be assayed with ease. Due to the broad range of the assay, the concentration of the sample is not a particular problem, and samples above the upper cutoff value can be serially diluted in the microtiter plate to find an appropriate value.

Animals↗