Serum Mucin-1 Research Articles

Colorimetric aptasensor based on magnetic beads and gold nanoparticles for detecting mucin 1

In this work, a colorimetric aptasensor based on magnetic beads (MBs), gold nanoparticles (AuNPs) and Horseradish Peroxidase (HRP) was prepared for the detection of mucin 1 (MUC1). Complementary DNA of the MUC1 aptamer (Apt) immobilized on the MBs was combined with the prepared AuNPs-Apt-HRP complex (AuNPs@Apt-HRP). In the presence of MUC1, it specifically bound to Apt, resulting in the detachment of gold nanoparticles from the MBs. After magnetic separation, AuNPs@Apt-HRP was separated into the supernatant and reacted with 3,3′,5,5′-Tetramethylbenzidine (TMB) to produce color reaction from colorless to blue. The linear range of MUC1 was from 75 to 500 μg/mL (R2 = 0.9878), and the detection limit was 41.95 μg/mL. The recovery rate of MUC1 in human serum was 99.18 %∼101.15 %. This method is simple and convenient. Moreover, it does not require complex and expensive equipment for detection of MUC1. It provides value for the development of MUC1 colorimetric sensors and a promising strategy for the determination of MUC1 in clinical diagnosis.

Serum Galectin-3 and Mucin-1 (CA15-3) in Relation to Renal Function in Untreated Chinese Patients.

Galectin-3 is a multi-functional lectin protein and a ligand of mucin-1 (CA15-3), and has been linked to renal fibrosis in animal models and renal function in humans. However, no population study has ever explored the associations with both ligand and receptor. We therefore investigate the independent association of renal function with serum galectin-3 and mucin-1 (CA15-3) in untreated Chinese patients. The study participants were outpatients who were suspected of hypertension, but had not been treated with antihypertensive medication. Serum galectin-3 and mucin-1 (CA15-3) concentrations were both measured by the enzyme-linked immunosorbent assay (ELISA) method. Estimated glomerular filtration rate (eGFR) was calculated from serum creatinine by the use of the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation. The 1,789 participants included 848 (47.4%) men. Mean (±SD) age was 51.3 ± 10.7 years. Multiple regression analyses showed that eGFR was significantly associated with serum galectin-3 and mucin-1 (CA15-3) concentration (0.68 and 1.32 ml/min/1.73 m2 decrease per 1-SD increase in log transformed serum galectin-3 and mucin-1 (CA15-3) concentration, respectively; P ≤ 0.006). The association of eGFR with serum mucin-1 (CA15-3) concentration was significantly stronger in the overweight (BMI 24.0-27.9 kg/m2) and obese (BMI ≥ 28.0 kg/m2) than in normal weight subjects (BMI < 24.0 kg/m2, P for interaction 0.018). Path analysis showed that serum galectin-3 concentration had both a direct (P = 0.016) and a mucin-1 mediated indirect effect (P = 0.014) on eGFR. Both circulating galectin-3 and mucin-1 (CA15-3) were significantly associated with renal function. The role of galectin-3 on renal function might be partially via mucin-1.

Levels of MUC1 in tumours and serum of patients with different sub-types of squamous cell carcinoma of the head and neck.

Mucin 1 (MUC1) is a membrane-bound and secreted glycoprotein that has a protective role in surface epithelia. We recently demonstrated that MUC1 mRNA expression was upregulated in tumour-free tongue tissues adjacent to squamous cell carcinoma of the oral tongue (SCCOT) compared with that in the tumour tissues. The present study investigated MUC1 protein in SCCOT tissue and serum from patients with squamous cell carcinoma of the head and neck (SCCHN) at different sub-sites. The results from immunohistochemistry demonstrated that all SCCOT tissues expressed MUC1; however, the protein levels were not correlated with MUC1 mRNA levels in the same tumours. Furthermore, serum MUC1 level was lower in patients with SCCOT, tonsil SCC and gingival SCC compared with that in healthy subjects; however, the difference was only significant for patients with SCCOT (P=0.0421). No correlation was seen between MUC1 level in tumour tissues and MUCI level in serum from the same patients. The absence of correlation between MUC1 protein and mRNA levels in SCCOT tissues emphasized the importance of validating genomic data in clinical samples. Although significant MUC1 downregulation was observed in the serum of patients with SCCOT, there was a large variation within the groups, suggesting that MUC1 may not be used as a biomarker for these types of tumors.

Multiple signal amplification via coupling DNAzyme with strand displacement reaction for sensitive colorimetric analysis of MUC1

Mucin 1 (MUC1) is abnormally expressed in tumor tissues, and quantitative analysis of MUC1 is thus beneficial to the prevention and early diagnosis of cancer. In this work, by intergrating DNAzyme with strand displacement reaction (SDR), we have fabricated a highly sensitive MUC1 colorimetric assay based on a multiple signal amplification strategy. Specifically, the presence of MUC1 can induce the exposure of the toehold region pre-locked in the aptamer probe (AP) to initiate SDR, liberating the MUC1/AP complex for recycling (cycle I) and forming the dimer-like DNAzyme. The formed DNAzyme can then cyclically cleave the substrate signal probe (cycle II), triggering the formation of G-quadruplex sequence and the new active enzyme sequence that can also cleave the signal probe (cycle III). Such target-induced triple amplification reaction can generate massive G-quadruplex sequences, which leads to a dramatically enhanced colorimetric signal for sensitive detection of MUC1 even at an ultra-low level of 35 pM. The colorimetric strategy also holds a high selectivity to distinguish MUC1 from other interfering proteins and can be successfully applied to the detection of MUC1 in human serum as well as cancer cells, presenting great potential in biosensing and clinical diagnostics.

Cascaded multiple recycling amplifications for aptamer-based ultrasensitive fluorescence detection of protein biomarkers.

Highly sensitive detection of molecular biomarkers plays a significant role in diagnosing various types of diseases at the early stage. We demonstrated in this paper an ultrasensitive aptamer-based fluorescence method for detecting mucin 1 (MUC1) in human serum via a cascaded multiple recycling signal amplification strategy. The MUC1 target molecules present in the samples cause structure switching of the hairpin aptamer probes, which initiates three cascaded recycling cycles for the cleavage of the fluorescently quenched signal probes to recover significant fluorescence for highly sensitive detection of MUC1. The developed method has a linear range from 100 fM to 1 nM for MUC1 detection. Besides, owing to the substantial signal amplification by the integrated and cascaded recycling cycles, a low detection limit of 35 fM is achieved with high selectivity. Moreover, the monitoring of trace MUC1 in human serum can also be realized with such a method, indicating its great potential for highly sensitive detection of different disease biomarkers.

Clinical value of a diagnostic score for colon cancer based on serum CEA, CA19-9, cytokeratin-1 and mucin-1

Background: Although established markers such as CEA and CA19-9 are important for diagnosing early stages of colon cancer, they are not ideal. Developing promising markers include cytokeratin 1 (CK1) and mucin-1 (MUC1), but the combined value of each of these markers is unclear. We therefore evaluated the value of a combined laboratory-based score of these four markers in the diagnosis of colon cancer.Methods: Two hundred patients who had undergone colonoscopic examination (150 colon cancer, 50 benign growths) were recruited. The study was controlled by 35 healthy subjects. CEA, CA19-9, CK1 and MUC1 were measured by ELISA and evaluated for cancer diagnosis using area under the receiver operating characteristic curve (AUC).Results: Serum levels of all four markers were increased in the order colon cancer > benign disease > healthy controls (p < 0.001). In multivariate analysis, CA19.9 (p = 0.025), CK1 (p < 0.001) and MUC1 (p = 0.009) were significant independent predictors of colon cancer. A score that gave the greatest power of discrimination for colon cancer was defined as 1.06 + [0.001 × CA19.9 result] + [0.003 × CEA result] + [0.03 × CK1 result] + [0.05 × MUC1 result]. The colon score provided superior discrimination, AUC, and sensitivity and specificity for colon cancer versus benign growth than each of the individual markers. Similarly, the colon score provided superior AUC, and sensitivity and specificity that each individual marker for tumour stage, lymph node invasion and distant organ metastases than each individual marker.Conclusion: A colon score derived from serum CEA, CA19-9, CK1 and MUC1 is a potential valuable non-invasive index that could be used for detection and screening early stage colon cancer patients.

Effects of Laparoscopic Cholecystectomy on Mucin1 and Cholesterol Ester Transfer Protein Status in Bangladeshi patients with Cholelithiasis

Objective: Although it was reported that cholecystectomy had profound impact on lipid profile and lipoprotein (a) status, no studies were reported on Mucin1 and cholesterol ester transfer protein (CETP) in Bangladeshi patients with cholelithiasis i.e. gallstone disease (GD). The present study was done about effects of laparoscopic cholecystectomy on Mucin1 and CETP status in Bangladeshi patients with cholelithiasis.Patients & Methods: Forty-four adult GD patients with cholelithiasis and 30 normal controls (NC) subjects were included in the study. The blood was taken from fasting patients before cholecystectomy (Serum-I°), gall bladder bile during cholecystectomy (Bile-I°) and blood again after 2-3 months at follow-up (Serum-II°) and from fasting NC subjects. Mucin1 and CETP levels were quantified in serum and bile by enzyme immunoassay (EIA) method using commercially available research kits. The results were compared by appropriate statistical tests using SPSS program.Results: Serum levels of both Mucin1 and CETP were increased in Pt-I°(S) compared to NC-I°(S) which were reduced after cholecystectomy in Pts-II°(S). However, serum CETP mean level in Pts-I°(S) was not significantly higher than NC-I°(S).The Mucin1 and CETP levels in patients bile, i.e. Pt-I°(B), were lower compared to serum levels before, Pt-I°(S), and after, (Pt-II°(S), cholecystectomy [Mucin1 (ng/ml): Pts-I°(S): 10.77 ± 2.93, Pts-I°(B): 1.29 ± 1.21, Pts II°(S): 6.67 ± 2.03, NCs(I°): 4.63 ± 0.53; CETP (μg/ml): Pts-I°(S): 11.47 ± 5.04, Pts-I°(B): 1.16 ± 1.19, Pts-II°(S): 9.41 ± 2.42, NCs (I°): 9.57 ± 3.63] . A significantly large proportion of patients had higher levels of Mucin1, but large number of patients had CETP levels within the normal range in Pt-I°(S). Interestingly, this was changed after cholecystectomy that significant proportion of patients had higher CETP levels in Pt-II°(S).Conclusions: Alterations in serum Mucin1 and CETP status were significant but complex and laparoscopic cholecystectomy had significant impact indicating an important function of gallbladder relevant to their metabolism. Further studies are needed on prevalence and frequency of metabolic syndrome, insulin resistance, cytokines and other relevant parameters in Bangladeshi patients with GD i.e. cholelithiasis.

Development and application of a double- antibody sandwich ELISA kit for the detection of serum MUC1 in lung cancer patients.

Mucin 1 (MUC1), as an oncogene, plays an important role in the diagnosis of lung cancer. To establish a double-antibody sandwich enzyme-linked immune sorbent assay (ELISA) kit for the detection of serum MUC1 in lung cancer patients. Commercial mouse anti-human MUC1 monoclonal antibody and rabbit anti-human MUC1 polyclonal antibody were used to construct a double-antibody sandwich ELISA kit. The serum MUC1 levels in peripheral blood of lung disease patients and healthy individuals were detected by the double-antibody sandwich ELISA kit and CA15-3 kit, respectively. A double-antibody sandwich ELISA kit was successfully constructed, and the sensitivity was up to 0.5 μ g/l. The cut-off value for the serum MUC1 levels in the peripheral blood was 1.98 μ g/l, the sensitivity was 62.5%, the specificity was 100% and the Youden index was 0.6250 when detected by the double-antibody sandwich ELISA kit, while the sensitivity was 18.75%, the specificity was 100% and the Youden index was 0.1875 when detected by CA15-3 kit. The double-antibody sandwich ELISA kit is superior to the CA15-3 kit in the detection of serum MUC1 in lung cancer patients, suggesting an attractive applying of the double-antibody sandwich ELISA kit in the early diagnosis of lung cancer.

Differential expression of mucins in Middle Eastern patients with colorectal cancer.

Mucin overexpression has been implicated in the tumorigenesis and progression of colorectal carcinoma (CRC). However, data obtained on the prognostic importance of mucin expression in CRC is inconsistent. Due to lack of data on mucin expression and the increase in CRC incidence in Saudi Arabia, the aim of the present study was to analyze the mucin expression profile in patients with CRC in this ethnic group. The present study consisted of 22 patients that underwent surgery for CRC. Histopathological and immunohistochemical staining was performed on CRC tumor and adjacent normal tissues. A tissue microarray was prepared from the tumor and normal adjacent samples to investigate the mucin expression profile using immunohistochemistry. Formalin-fixed paraffin-embedded human colorectal cancer tissues were immunostained with mucin 1 (MUC1), mucin 2 (MUC2) and mucin 5AC (MUC5AC) antibodies. Associations between mucin expression and histopathological variables were evaluated. The present study indicated that MUC1 was highly expressed in early (stage I and II; P=0.0016) and late (stage III and IV; P<0.0001) stage CRC tissues compared to normal adjacent tissues. However, MUC2 expression was observed to be downregulated in early and late stage CRC tissues compared to normal and adjacent tissues. Furthermore, serum MUC1 levels were observed to be increased in early and late stage CRC. The present findings indicate that MUC1 expression was significantly higher in early and late stage CRC tissues and MUC2 was downregulated in CRC tissues compared with normal adjacent tissues, and serum MUC1 protein was significantly higher in CRC patients compared to control serum. In conclusion, during colorectal tumorigenesis the pattern of MUC1 and MUC2 expression is altered in Saudi Arabian patients with CRC compared with normal. A higher expression of MUC1 may be used as an independent biomarker in various stages of CRC tumors, which would aid in the early detection of CRC.

Immunobiology of human mucin 1 in a preclinical ovarian tumor model

Epithelial ovarian cancer is an aggressive malignancy, with a low 5-year median survival. Continued improvement on the development of more effective therapies depends in part on the availability of adequate preclinical models for in vivo testing of treatment efficacy. Mucin 1 (MUC1) glycoprotein is a tumor-associated antigen overexpressed in ovarian cancer cells, making it a potential target for immune therapy. To create a preclinical mouse model for MUC1-positive ovarian tumors, we generated triple transgenic (Tg) mice that heterozygously express human MUC1(+/-) as a transgene, and carry the conditional K-rasG12D oncoallele (loxP-Stop-loxP-K-ras(G12D/+)) and the floxed Pten gene (Pten/(loxP/loxP)). Injection of Cre recombinase-encoding adenovirus (AdCre) in the ovarian bursa of triple (MUC1KrasPten) Tg mice triggers ovarian tumors that, in analogy to human ovarian cancer, express strongly elevated MUC1 levels. The tumors metastasize loco-regionally and are accompanied by high serum MUC1, closely mimicking the human disease. Compared with the KrasPten mice with tumors, the MUC1KrasPten mice show increased loco-regional metastasis and augmented accumulation of CD4+Foxp3+ immune-suppressive regulatory T cells. Vaccination of MUC1KrasPten mice with type 1 polarized dendritic cells (DC1) loaded with a MUC1 peptide (DC1-MUC1) can circumvent tumor-mediated immune suppression in the host, activate multiple immune effector genes and effectively prolong survival. Our studies report the first human MUC1-expressing, orthotopic ovarian tumor model, reveal novel MUC1 functions in ovarian cancer biology and demonstrate its suitability as a target for immune-based therapies.

Effects of molecular structural variants on serum Krebs von den Lungen-6 levels in sarcoidosis

BackgroundSerum Krebs von den Lungen-6 (KL-6), which is classified as human mucin-1 (MUC1), is used as a marker of sarcoidosis and other interstitial lung diseases. However, there remain some limitations due to a lack of information on the factors contributing to increased levels of serum KL-6. This study was designed to investigate the factors contributing to increased levels of serum KL-6 by molecular analysis.MethodsWestern blot analysis using anti-KL-6 antibody was performed simultaneously on the bronchoalveolar lavage fluid (BALF) and serum obtained from 128 subjects with sarcoidosis.ResultsKL-6/MUC1 in BALF showed three bands and five band patterns. These band patterns were associated with the MUC1 genotype and the KL-6 levels. KL-6/MUC1 band patterns in serum were dependent on molecular size class in BALF. Significantly increased levels of serum KL-6, serum/BALF KL-6 ratio and serum soluble interleukin 2 receptor were observed in the subjects with influx of high molecular size KL-6/MUC1 from the alveoli to blood circulation. The multivariate linear regression analysis involving potentially relevant variables such as age, gender, smoking status, lung parenchymal involvement based on radiographical stage and molecular size of KL-6/MUC1 in serum showed that the molecular size of KL-6/MUC1 in serum was significant independent determinant of serum KL-6 levels.ConclusionsThe molecular structural variants of KL-6/MUC1 and its leakage behavior affect serum levels of KL-6 in sarcoidosis. This information may assist in the interpretation of serum KL-6 levels in sarcoidosis.

Flow cytometry-based assay to evaluate human serum MUC1-Tn antibodies

Mucin-1 (MUC1) is a heavily O-glycosylated, transmembrane protein that is expressed on the apical surface of most secretory epithelia. In malignantly transformed epithelia, MUC1 has lost its apical distribution, is underglycosylated and is secreted into the circulation. Due to the underglycosylation of MUC1, cancer-specific MUC1-Tn/STn antigens, which are highly immunogenic, become exposed. We aimed at developing a system that allows detection of antibodies directed to the native form of MUC1 and the underglycosylated MUC1-Tn epitopes. To this end, we made use of the Chinese Hamster Ovary (CHO) ldlD cell line stably transfected with MUC1. This cell line has a glycosylation defect, which can be reversed by addition of different monosaccharides to the cell culture and enables the production of cells expressing the MUC1-Tn glycoforms. After validation with glycospecific antibodies, the CHO-ldlD MUC1 system was used to detect serum MUC1 and MUC1-Tn antibodies. Using this system, we could confirm the presence of MUC1-Tn antibodies in the serum of a patient vaccinated with a truncated MUC1 peptide. This indicates that the CHO-ldlD MUC1 system represents a flow cytometry-based technique to detect antibodies binding to the underglycosylated MUC1 protein. This cellular system is complementary to the previously published methods to detect MUC1 serum antibodies, since the antibodies to the native protein are evaluated and therefore it can be effectively used for MUC1 antibody monitoring in vaccination studies as well as for functional assays.

Serum mucin antigen (CASA) as a marker of amiodarone-induced pulmonary toxicity.

Amiodarone is used to treat life-threatening cardiac arrhythmias. Amiodarone-induced pulmonary toxicity (APT) can be difficult to diagnose. APT may result in increased mucus production and mucin expression. Thus, serum mucin-1 was evaluated as a marker for amiodarone-induced pulmonary toxicity. Concentrations of mucin-1 in peripheral blood were determined using cancer-associated serum antigen (CASA) assay in patients taking amiodarone. Eight of ten patients who developed major amiodarone toxicity had high serum CASA levels. Patients with toxicity had a significantly higher mean rank CASA concentration compared with those without major toxicity. CASA shows potential as a marker for amiodarone-induced toxicity, particularly pulmonary toxicity.