• Korean Journal of Clinical Oncology
• /
• v.14 no.2
• /
• pp.89-94
• /
• 2018

Purpose: To investigate the relationship between MUC expression and clinicopathologic factors in advanced gastric cancer. Methods: A total of 237 tumor specimens were assessed for MUC expression by immunohistochemistry. The clinicopathologic factors were investigated with MUC1, MUC2, MUC5AC, and MUC6. Results: MUC1, MUC2, MUC5AC, and MUC6 expression was identified in 148 of 237 (62.4%), 141 of 237 (59.5%), 186 of 237 (78.5%), and 146 of 237 (61.6%) specimens, respectively. MUC1 expression was correlated with age, human epidermal growth factor receptor 2 (HER2) status, lymphatic invasion, Lauren classification and histology. Further multivariate logistic regression analysis revealed a significant correlation between MUC1expression and lymphatic invasion, diffuse type of Lauren classification. MUC5AC expression was correlated with HER2 status, Lauren classification and histology. Further multivariate logistic regression analysis revealed a significant correlation between MUC5AC expression and HER2 status, diffuse and mixed type of Lauren classification. MUC2 and MUC6 expression were not correlated with clinicopathologic factors. The patients of MUC1 expression had poorer survival than those without MUC1 expression, but MUC2, MUC5AC or MUC6 were not related to survival. In an additional multivariate analysis that used the Cox proportional hazards model, MUC1 expression was not significantly correlated with patient survival independent of age, N-stage, and venous invasion. Conclusion: When each of these four MUCs expression is evaluated, in light of clinicopathologic factors, MUC1 expression may be considered as a prognostic factor in patients with advanced gastric cancer. Therefore, careful follow-up may be necessary because the prognosis is poor when MUC1 expression is present.

• Tuberculosis and Respiratory Diseases
• /
• v.80 no.1
• /
• pp.60-68
• /
• 2017

Background: Mucus hypersecretion from airway epithelium is a characteristic feature of airway inflammatory diseases. Tumor necrosis factor ${\alpha}$ (TNF-${\alpha}$) regulates mucin synthesis. Glucocorticoids including mometasone fuorate (MF) have been used to attenuate airway inflammation. However, effects of MF on mucin production have not been reported. Methods: Effects of MF and budesonide (BUD) on the phorbol-12-myristate-13-acetate (PMA)-induction of mucin and TNF-${\alpha}$ in human airway epithelial cells (NCI-H292) were investigated in the present study. Confluent NCI-H292 cells were pretreated with PMA (200 nM) for 2 hours. Subsequently, the cells were stimulated with MF (1-500 ng/mL) or BUD (21.5 ng/mL) for 8 hours. Dexamethasone ($1{\mu}g/mL$) was used as the positive control. Real-time polymerase chain reaction was used to determine MUC2 and MUC5AC mRNA levels. The level of total mucin, MUC2, MUC5AC, and TNF-${\alpha}$ in culture supernatants were measured using enzyme-linked immunosorbent assay. Results: MF and BUD significantly suppressed MUC2 and MUC5AC gene expression in PMA-stimulated NCI-H292 cells. The inhibitory effects of the two steroid drugs were also observed in the production of total mucin, MUC2 and MUC5AC proteins, and TNF-${\alpha}$. Conclusion: Our findings demonstrated that MF and BUD attenuated mucin and TNF-${\alpha}$ production in PMA-induced human airway epithelial cells.

• Molecules and Cells
• /
• v.46 no.11
• /
• pp.700-709
• /
• 2023

Mucus hyperproduction and hypersecretion are observed often in respiratory diseases. MUC8 is a glycoprotein synthesized by epithelial cells and generally expressed in the respiratory track. However, the physiological mechanism by which extracellular nucleotides induce MUC8 gene expression in human airway epithelial cells is unclear. Here, we show that UTP could induce MUC8 gene expression through P2Y2-PLCβ3-Ca²⁺ activation. Because the full-length cDNA sequence of MUC8 has not been identified, a specific siRNA-MUC8 was designed based on the partial cDNA sequence of MUC8. siRNA-MUC8 significantly increased TNF-α production and decreased IL-1Ra production, suggesting that MUC8 may downregulate UTP/P2Y2-induced airway inflammation. Interestingly, the PDZ peptide of ZO-1 protein strongly abolished UTP-induced TNF-α production and increased IL-1Ra production and MUC8 gene expression. In addition, the PDZ peptide dramatically increased the levels of UTP-induced ZO proteins and TEER (trans-epithelial electrical resistance). These results show that the anti-inflammatory mucin MUC8 may contribute to homeostasis, and the PDZ peptide can be a novel therapeutic candidate for UTP-induced airway inflammation.

• BMB Reports
• /
• v.50 no.10
• /
• pp.516-521
• /
• 2017

$CLB_{2.0}$, a constituent of PM, induces secretion of multiple cytokines and chemokines that regulate airway inflammation. Specifically, IL-6 upregulates $CLB_{2.0}$-induced MUC5AC and MUC1 expression. Interestingly, of the tight junction proteins examined, claudin-1 expression was inhibited by $CLB_{2.0}$. While the overexpression of claudin-1 decreased $CLB_{2.0}$-induced MUC5AC expression, it increased the expression of the anti-inflammatory mucin, MUC1. $CLB_{2.0}$-induced IL-6 secretion was mediated by ROS. The ROS scavenger N-acetyl-cysteine inhibited $CLB_{2.0}$-induced IL-6 secretion, thereby decreasing the $CLB_{2.0}$-induced MUC5AC expression, whereas $CLB_{2.0}$-induced MUC1 expression increased. $CLB_{2.0}$ activated the ERK1/2 MAPK via a ROS-dependent pathway. ERK1/2 downregulated the claudin-1 and MUC1 expressions, whereas it dramatically increased $CLB_{2.0}$-induced MUC5AC expression. These findings suggest that $CLB_{2.0}$-induced ERK1/2 activation acts as a switch for regulating inflammatory conditions though a ROS-dependent pathway. Our data also suggest that secreted IL-6 regulates $CLB_{2.0}$-induced MUC5AC and MUC1 expression via ROS-mediated downregulation of claudin-1 expression to maintain mucus homeostasis in the airway.

• BMB Reports
• /
• v.54 no.8
• /
• pp.425-430
• /
• 2021

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces coronavirus disease 2019 (COVID-19) and may increase the risk of adverse outcomes in lung cancer patients. In this study, we investigated the expression and function of mucin 1 (MUC1) after SARS-CoV-2 infection in the lung epithelial cancer cell line Calu-3. MUC1 is a major constituent of the mucus layer in the respiratory tract and contributes to pathogen defense. SARS-CoV-2 infection induced MUC1 C-terminal subunit (MUC1-C) expression in a STAT3 activation-dependent manner. Inhibition of MUC1-C signaling increased apoptosis-related protein levels and reduced proliferation-related protein levels; however, SARS-CoV-2 replication was not affected. Together, these results suggest that increased MUC1-C expression in response to SARS-CoV-2 infection may trigger the growth of lung cancer cells, and COVID-19 may be a risk factor for lung cancer patients.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.12
• /
• pp.6447-6453
• /
• 2012

Background: The mucin components of the gastric gel layer function as a protective and lubricating factor against luminal acid and proteolytic enzymes. Alteration of mucin expression in gastric preneoplastic and neoplastic lesions has suggested potential roles in neoplastic processes. This study aimed to assess the clinicopathological and prognostic significance of MUC-2, MUC-4 and MUC-5AC in Japanese gastric cancer. Methods: Expression of MUC-2, -4 and -5AC was evaluated on tissue microarrays of gastric carcinomas and adjacent non-cancerous mucosa specimens by immunohistochemistry and compared with clinicopathological parameters and survival time of the patients. Results: The three mucins were found to be expressed to a lesser extent in gastric carcinomas in comparison with non-cancerous mucosa (p<0.05). MUC-2 expression was negatively correlated with tumor size, depth of invasion, and TNM staging of gastric cancer (p<0.05), while that of MUC-5AC was negatively associated with the depth of invasion, venous invasion, lymph node metastasis and TNM staging (p<0.05), but positively with MUC-4 and MUC-2 expression (p<0.05). There was higher MUC-2 expression in intestinal- than diffuse-type carcinomas (p<0.05). Kaplan-Meier analysis indicated no relationship between expression of the three mucins and the cumulative survival rate of patients, even stratified according to the depth of invasion (p>0.05). Conclusion: Down-regulated expression of MUC-2, -4 and -5AC may be involved in pathogenesis, invasion, metastasis or differentiation of gastric carcinoma. Their altered expression might therefore be employed as an indicator of pathobiological behavior.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.1
• /
• pp.127-131
• /
• 2013

Trastuzumab is the first molecular targeting drug to increase the overall survival rate in advanced gastric cancer. However, it has also been found that a high intrinsic or primary trastuzumab resistance exists in some proportion of gastric cancer patients. In order to explore the mechanism of resistance to trastuzumab, firstly we investigated the expression of MUC1 (membrane-type mucin 1) in gastric cancer cells and its relationship with drug-resistance. Then using gene-silencing, we transfected a siRNA of MUC1 into drug-resistant cells. The results showed the MKN45 gastric cell line to be resistant to trastuzumab, mRNA and protein expression of MUC1 being significantly upregulated. After transfection of MUC1 siRNA, protein expression of MUC1 in MKN45cells was significantly reduced. Compared with the junk transfection and blank control groups, the sensitivity to trastuzumab under MUC1 siRNA conditions was significantly increased. These results imply that HER2-positive gastric cancer cell MKN45 is resistant to trastuzumab and this resistance can be cancelled by silencing expression of the MUC1 gene.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.12
• /
• pp.6349-6355
• /
• 2012

Previous studies showed that Math1 homologous to human Hath1 can cause mouse goblet cells to differentiate. In this context it is important that the majority of colon cancers have few goblet cells. In the present study, the potential role of Hath1 in colon carcinogenesis was investigated. Sections of paraffin-embedded tissues were used to investigate the goblet cell population of normal colon mucosa, mucosa adjacent colon cancer and colon cancer samples from 48 patients. Hath1 and Muc2 expression in these samples were tested by immunohistochemistry, quantitative real-time reverse transcription -PCR and Western blotting. After the recombinant plasmid, pcDNA3.1(+)-Hath1 had been transfected into HT29 colon cancer cells, three clones were selected randomly to test the levels of Hath1 mRNA, Muc2 mRNA, Hath1, Muc2, cyclin D1 and p27 by quantitative real-time reverse transcription-PCR and Western blotting. Moreover, the proliferative ability of HT29 cells introduced with Hath1 was assessed by means of colony formation assay and xenografting. Expression of Hath1, Muc2, cyclin D1 and p27 in the xenograft tumors was also detected by Western blotting. No goblet cells were to be found in colon cancer and levels of Hath1 mRNA and Hath1, Muc2 mRNA and Muc2 were significantly down-regulated. Hath1 could decrease cyclin D1, increase p27 and Muc2 in HT29 cells and inhibit their proliferation. Hath1 may be an anti-oncogene in colon carcinogenesis.

• Asian Pacific Journal of Cancer Prevention
• /
• v.17 no.1
• /
• pp.335-339
• /
• 2016

Background: The aim of this work was to investigate if serum and salivary auto-antibodies, isotypes IgG and IgM, against HER2 and MUC1 tandem repeat fragments could play a role in breast cancer screening. Materials and Methods: Our case-control study was conducted in breast cancer patients, in early stages (n=29), at the gynecology service, Maternity Souissi Hospital, Rabat, Morocco and healthy woman (n=31). Salivary and serum auto-antibodies against HER2 and MUC1 (tandem repeat) were assessed by enzyme-linked immunosorbent assay (ELISA) and compared between patients and healthy women using the Mann-Whitney U test. A P-value <0.05 was considered to be statistically significant. Results: Our data showed higher expression of all serum and salivary autoantibodies in patients as compared to healthy women p<0.05. However, serum IgM anti-MUC1 expression did not show a significant difference between cases and controls (p=0.79). Similarly, salivary IgG anti-HER2 expression did not differ (p=0.15). The correlation between the different isotypes of antibodies revealed that the highest correlation was between salivary IgG anti-HER2 and salivary IgG anti-MUC1(r=0.65). In fact, we have found in saliva the correlation between autoantibodies anti-MUC1 and anti-HER2 more important than in serum (r=0.59 and r=0. 55). However, the correlation between serum and saliva values for all antibodies was weak. Conclusions: Autoantibodies against HER2 and MUC1 may provide a useful approach in breast cancer screening when using both serum and saliva values.

• Tuberculosis and Respiratory Diseases
• /
• v.58 no.6
• /
• pp.590-599
• /
• 2005

Object : Cigarette smoking is a major cause of mucus hypersecretion, which is a pathophysiological feature of many inflammatory airway diseases. Mucins, which are an important part of the airway mucus, are synthesized from the Muc gene in airway epithelial cells. However, the signaling pathways for cigarette smoke-induced mucin synthesis are unknown. The aim of this study was to determine the signal pathway for smoking induced Muc5ac gene expression. Methods : A549 cells were cultured and transiently transfected with the Muc5ac promoter fragment. These cells were stimulated with 5% cigarette smoke extract (CSE) alone or with CSE after a pretreatment with various signal transduction pathway inhibitors (AG1478, PD98059 and SB203580). The Muc5ac promoter activity was examined using the luciferase reporter system, and the level of phosphorylated EGFR, ERK1/2, p38 MAPK and JNK were all examined using Western blot analysis. Muc5ac mRNA expression was also examined using reverse transcriptase polymerase chain reactions (RT-PCR). Results : 1. The peak level of luciferase activity of the Muc5ac promoter was observed at 5% concentration and after 3 hours of incubation with the CSE. The level of EGFR phosphorylation and the luciferase activity of the transfected cells caused by the CSE were significantly suppressed by AG1478 or PD98059 (P<0.01). 2. CSE phosphorylated ERK1/2 or p38 MAPK but not JNK. The Muc5ac mRNA expression level was increased by the CSE but that was suppressed by PD98059 or AG1478. 3. The CSE-induced phosphorylation of ERK1/2 was blocked by PD98059 and that of p38 MAPK was blocked by either PD98059 or SB203580. Either PD98059 or SB203580 suppressed the luciferase activity of the transfected cells (P<0.0001). Conclusion : The Muc5ac mRNA expression level was increased by the CSE. The increased CSE-induced transcriptional activity was mediated via EGF receptor activation, which led to ERK1/2 and p38 MAPK phosphorylation.