Expression and prognostic relevance of MUC1 in stage IB non-small cell lung cancer

MUC1-EGFR crosstalk with IL-6 by activating NF-κB and MAPK pathways to regulate the stemness and paclitaxel-resistance of lung adenocarcinoma

BACKGROUND

The chemotherapy resistance often leads to chemotherapy failure. This study aims to explore the molecular mechanism by which MUC1 regulates paclitaxel resistance in lung adenocarcinoma (LUAD), providing scientific basis for future target selection.

METHODS

The bioinformatics method was used to analyse the mRNA and protein expression characteristics of MUC1 in LUAD. RT-qPCR and ELISA were used to detect the mRNA and protein expression, flow cytometry was used to detect CD133+ cells, and cell viability was detected by CCK-8 assay. The mRNA-seq was performed to analyse the changes in expression profile, GO and KEGG analysis were used to explore the potential biological functions.

RESULTS

MUC1 is highly expressed in LUAD patients and is associated with a higher tumour infiltration. In paclitaxel resistance LUAD cells (A549/TAX cells), the expression of MUC1, EGFR/p-EGFR and IL-6 were higher than that of A549 cells, the proportion of CD133+ cells was significantly increased, and the expression of cancer stem cell (CSCs) transcription factors (NANOG, OCT4 and SOX2) were significantly up-regulated. After knocking down MUC1 in A549/Tax cells, the activity of A549/Tax cells was significantly decreased. Correspondingly, the expression of EGFR, IL-6, OCT4, NANOG, and SOX2 were significantly down-regulated. The mRNA-seq showed that knocking down MUC1 affected the gene expression, DEGs mainly enriched in NF-κB and MAPK signalling pathway.

CONCLUSION

MUC1 was highly expressed in A549/TAX cells, and MUC1-EGFR crosstalk with IL-6 may be due to the activation of NF-κB and MAPK pathways, which promote the enrichment of CSCs and lead to paclitaxel resistance.

Molecular Stratification and Treatment Monitoring of Lung Cancer Using a Small Extracellular Vesicle-Activated Nanocavity Architecture

Development of molecular diagnostics for lung cancer stratification and monitoring is crucial for the rational planning and timely adjustment of treatments to improve clinical outcomes. In this regard, we propose a nanocavity architecture to sensitively profile the protein signature on small extracellular vesicles (sEVs) to enable accurate, noninvasive staging and treatment monitoring of lung cancer. The nanocavity architecture is formed by molecular recognition through the binding of sEVs with the nanobox-based core-shell surface-enhanced Raman scattering (SERS) barcodes and mirrorlike, asymmetric gold microelectrodes. By imposing an alternating current on the gold microelectrodes, a nanofluidic shear force was stimulated that supported the binding of sEVs and the efficient assembly of the nanoboxes. The binding of sEVs further induced a nanocavity between the nanobox and the gold microelectrode that significantly amplified the electromagnetic field to enable the simultaneous enhancement of Raman signals from four SERS barcodes and generate patient-specific molecular sEV signatures. Importantly, evaluated on a cohort of clinical samples (n = 76) on the nanocavity architecture, the acquired patient-specific sEV molecular signatures achieved accurate identification, stratification, and treatment monitoring of lung cancer patients, highlighting its potential for transition to clinical utility.

Antigen loss following CAR-T cell therapy: Mechanisms, implications, and potential solutions

Chimeric Antigen Receptor T-cell (CAR-T cell) therapy has emerged as a groundbreaking immunotherapeutic approach for treating various hematological malignancies. CAR-T cells are engineered to express synthetic receptors that target specific antigens on cancer cells, leading to their eradication. While the therapy has shown remarkable efficacy, a significant challenge that has been observed in 30%-70% of patients showing recurrent disease is antigen loss or downregulation. We searched PubMed/MEDLINE, EMBASE, and Google scholar for articles on antigen loss/escape following Chimeric antigen receptor T-cell therapy in malignancies. Antigen loss refers to the loss or reduction in the expression of the target antigen on cancer cells, rendering CAR-T cells ineffective. This phenomenon poses a significant clinical concern, as it can lead to disease relapse and limited treatment options. This review explores the mechanisms underlying antigen loss following CAR-T cell therapy, its implications on treatment outcomes, and potential strategies to overcome the problem.

Tandem CAR-T cells targeting MUC1 and PSCA combined with anti-PD-1 antibody exhibit potent preclinical activity against non-small cell lung cancer

Chimeric antigen receptor (CAR)-T cells encounter many issues when treating solid tumors, including tumor antigen heterogeneity and immunosuppression. United targeting of two tumor-associated antigens (TAAs) and blocking of PD-1 may solve this problem and enhance the function of CAR-T. Mucin 1 (MUC1) and prostate stem cell antigen (PSCA) are overexpressed in non-small cell lung cancer (NSCLC). Here, we constructed a bivalent tandem CAR-T (Tan CAR-T), which can simultaneously target MUC1 and PSCA and evaluated its effects of inhibiting non-small cell lung cancer (NSCLC) in vitro and in vivo. Results indicated that the tumor killing effect of these Tan CAR-T was more effective than that of single-target CAR-T, its antitumor efficacy could be further strengthened by anti-PD-1 antibody. Our study reported a previously unstudied therapeutic effect of a Tan CAR-T in NSCLC, providing a preclinical rationale for anti-PD-1 antibody combined with Tan CAR-T targeting MUC1 and PSCA in the treatment of NSCLC.

Glycomic, Glycoproteomic, and Proteomic Profiling of Philippine Lung Cancer and Peritumoral Tissues: Case Series Study of Patients Stages I-III

Lung cancer is the leading cause of cancer death and non-small cell lung carcinoma (NSCLC) accounting for majority of lung cancers. Thus, it is important to find potential biomarkers, such as glycans and glycoproteins, which can be used as diagnostic tools against NSCLC. Here, the N-glycome, proteome, and N-glycosylation distribution maps of tumor and peritumoral tissues of Filipino lung cancer patients (n = 5) were characterized. We present several case studies with varying stages of cancer development (I-III), mutation status (EGFR, ALK), and biomarker expression based on a three-gene panel (CD133, KRT19, and MUC1). Although the profiles of each patient were unique, specific trends arose that correlated with the role of aberrant glycosylation in cancer progression. Specifically, we observed a general increase in the relative abundance of high-mannose and sialofucosylated N-glycans in tumor samples. Analysis of the glycan distribution per glycosite revealed that these sialofucosylated N-glycans were specifically attached to glycoproteins involved in key cellular processes, including metabolism, cell adhesion, and regulatory pathways. Protein expression profiles showed significant enrichment of dysregulated proteins involved in metabolism, adhesion, cell-ECM interactions, and N-linked glycosylation, supporting the protein glycosylation results. The present case series study provides the first demonstration of a multi-platform mass-spectrometric analysis specifically for Filipino lung cancer patients.

Chimeric antigen receptor T cell therapy: challenges and opportunities in lung cancer

Chimeric antigen receptor (CAR) T-cell therapy has revolutionized the paradigm in hematological malignancies treatment, driving an ever-expanding number of basic research and clinical trials of genetically engineering T cells to treat solid tumors. CAR T-cell therapies based on the antibodies targeting Mesothelin, CEA, EGFR, EGFR, MUC1, DLL3, and emerging novel targets provide promising efficacy for lung cancer patients. However, clinical application of CAR T-cell therapy against lung cancer remains limited on account of physical and immune barriers, antigen escape and heterogeneity, on-target off-tumor toxicity, and many other reasons. Understanding the evolution of CAR structure and the generalizable requirements for manufacturing CAR T cells as well as the interplay between lung tumor immunology and CAR T cells will improve clinical translation of this therapeutic modality in lung cancer. In this review, we systematically summarize the latest advances in CAR T-cell therapy in lung cancer, focusing on the CAR structure, target antigens, challenges, and corresponding new strategies.

MUC3A promotes non-small cell lung cancer progression via activating the NFκB pathway and attenuates radiosensitivity

Mucin 3A (MUC3A) is highly expressed in non-small cell lung cancer (NSCLC), but its functions and effects on clinical outcomes are not well understood. Tissue microarray of 92 NSCLC samples indicated that high levels of MUC3A were associated with poor prognosis, advanced staging, and low differentiation. MUC3A knockdown significantly suppressed NSCLC cell proliferation and induced G1/S accumulation via downregulating cell cycle checkpoints. MUC3A knockdown also inhibited tumor growth in vivo and had synergistic effects with radiation. MUC3A knockdown increased radiation-induced DNA double strain breaks and γ-H2AX phosphorylation in NSCLC cells. MUC3A downregulation inhibited the BRCA-1/RAD51 pathway and nucleus translocation of P53 and XCRR6, suggesting that MUC3A promoted DNA damage repair and attenuated radiation sensitivity. MUC3A knockdown also resulted in less nucleus translocation of RELA and P53 in vivo. Immunoprecipitation revealed that MUC3A interacted with RELA and activated the NFκB pathway via promoting RELA phosphorylation and interfering the binding of RELA to IκB. Our studies indicated that MUC3A was a potential oncogene and associated with unfavorable clinical outcomes. NSCLC patients with a high MUC3A level, who should be more frequent follow-up and might benefit less from radiotherapy.

Role of EIF4G1 network in non-small cell lung cancers (NSCLC) cell survival and disease progression

Although the Eukaryotic Translation Initiation Factor 4 Gamma 1 (EIF4G1) has been found overexpressed in a variety of cancers, its role in non–small cell lung cancers (NSCLC) pathogenesis especially in immunoregulatory functions, its clinical relevance and therapeutic potential remain largely unknown. By using cancer patients tissue assays, the results indicate that EIF4G1 expressional levels are much higher in NSCLC tissues than in adjacent or normal lung tissues, which are also associated with NSCLC patient survival. By using an RNA‐Sequencing based pipeline, the data show that EIF4G1 has a significant association with immune checkpoint molecules such as PD‐1/PD‐L1 in NSCLC. EIF4G1 small‐molecule inhibitors effectively repress NSCLC growth in cell culture and xenograft animal models. Protein array results identify the signature of proteins controlled by EIF4G1 in NSCLC cells, in which new candidates such as MUC1 and NRG1 are required for NSCLC survival and tumorigenesis with clinical relevance. Taken together, these results have for the first time demonstrated the immunoregulatory functions, clinical relevance and therapeutic potential of the EIF4G1 network in NSCLC, which may represent a promising and novel target to improve lung cancer treatment.

The role of mucin 1 in respiratory diseases

Recent evidence has demonstrated that mucin 1 (MUC1) is involved in many pathological processes that occur in the lung. MUC1 is a transmembrane protein mainly expressed by epithelial and hematopoietic cells. It has a receptor-like structure, which can sense the external environment and activate intracellular signal transduction pathways through its cytoplasmic domain. The extracellular domain of MUC1 can be released to the external environment, thus acting as a decoy barrier to mucosal pathogens, as well as serving as a serum biomarker for the diagnosis and prognosis of several respiratory diseases such as lung cancer and interstitial lung diseases. Furthermore, bioactivated MUC1-cytoplasmic tail (CT) has been shown to act as an anti-inflammatory molecule in several airway infections and mediates the expression of anti-inflammatory genes in lung diseases such as chronic rhinosinusitis, chronic obstructive pulmonary disease and severe asthma. Bioactivated MUC1-CT has also been reported to interact with several effectors linked to cellular transformation, contributing to the progression of respiratory diseases such as lung cancer and pulmonary fibrosis. In this review, we summarise the current knowledge of MUC1 as a promising biomarker and drug target for lung disease.

Targeting Glycans and Heavily Glycosylated Proteins for Tumor Imaging

Simple Summary

Distinguishing malignancy from healthy tissue is essential for oncologic surgery. Targeted imaging during an operation aids the surgeon to operate better. The present tracers for detecting cancer are directed against proteins that are overexpressed on the membrane of tumor cells. This review evaluates the use of tumor-associated sugar molecules as an alternative for proteins to image cancer tissue. These sugar molecules are present as glycans on glycosylated membrane proteins and glycolipids. Due to their location and large numbers per cell, these sugar molecules might be better targets for tumor imaging than proteins.

Abstract

Real-time tumor imaging techniques are increasingly used in oncological surgery, but still need to be supplemented with novel targeted tracers, providing specific tumor tissue detection based on intra-tumoral processes or protein expression. To maximize tumor/non-tumor contrast, targets should be highly and homogenously expressed on tumor tissue only, preferably from the earliest developmental stage onward. Unfortunately, most evaluated tumor-associated proteins appear not to meet all of these criteria. Thus, the quest for ideal targets continues. Aberrant glycosylation of proteins and lipids is a fundamental hallmark of almost all cancer types and contributes to tumor progression. Additionally, overexpression of glycoproteins that carry aberrant glycans, such as mucins and proteoglycans, is observed. Selected tumor-associated glyco-antigens are abundantly expressed and could, thus, be ideal candidates for targeted tumor imaging. Nevertheless, glycan-based tumor imaging is still in its infancy. In this review, we highlight the potential of glycans, and heavily glycosylated proteoglycans and mucins as targets for multimodal tumor imaging by discussing the preclinical and clinical accomplishments within this field. Additionally, we describe the major advantages and limitations of targeting glycans compared to cancer-associated proteins. Lastly, by providing a brief overview of the most attractive tumor-associated glycans and glycosylated proteins in association with their respective tumor types, we set out the way for implementing glycan-based imaging in a clinical practice.

Comprehensive analysis of the mechanism and treatment significance of Mucins in lung cancer

Aberrant expression of mucin proteins has played a complex and essential role in cancer development and metastasis. Members of the mucin family have been intimately implicated in lung cancer progression, metastasis, survival and chemo-resistance. During the progression of lung cancer, mucin proteins have involved all of the procession of lung cancer, which is interacted with many receptor tyrosine kinases signal pathways and mediated cell signals for tumor cell growth and survival. Mucins thus have been considerable as the indicator of negative prognosis and desirable therapeutic targets of lung cancers. In this review, we comprehensively analyzed the role of each member of the mucin family in lung cancer by combining open-accessed database analysis and assembling cutting-edge information about these molecules.

Clinical Evaluation of Serum Tumor Markers in Patients With Advanced-Stage Non-Small Cell Lung Cancer Treated With Palliative Chemotherapy in China

Aim: This study aims to analyze the prognostic value of seven tumor makers and also investigate the response of palliative chemotherapy in advanced NSCLC patients with advanced disease.

Methods: Medical records of 278 advanced NSCLC Chinese patients who received six cycles of palliative chemotherapy were retrospectively reviewed under ethical approval (JSCH2019K-011). Univariate and multivariate Cox regression analyses were performed using SPSS 24 to find the clinical value of these tumor markers and to identify the factors that were associated with progression-free survival (PFS), as well as the response to palliative chemotherapy.

Results: In baseline characteristic, the high levels of CEA, CA-125, CA-199, AFP, NSE, CYFRA21-1, and CA15-3 were detected in 209 (75.18%), 139 (50.0%), 62 (22.30%), 18 (6.47%), 155 (55.75%), 176 (63.30%), and 180 (64.74%) patients, respectively. Univariate analysis revealed that patients with high vs. normal levels of all tumor markers had an increased risk of poor prognosis. In the multivariable Cox regression model, the patient with (high vs. normal) CYFRA21-1 levels (HR = 1.454, P = 0.009) demonstrated an increased poor PFS. However, patients with (high vs. normal) CA19-9 levels (HR = 0.524, P < 0.0001) and NSE levels (HR = 0.584, P < 0.0001) presented a decreased risk of PFS. Also, patients receiving 3-drugs regimen had better PFS compared to those on 2-drugs regimen (P = 0.043).

Conclusions: The high levels of CYFRA21-1 was correlated with a poor prognostic factor of PFS for Advanced NSCLC patients. However, the high levels of CA19-9 and NSE were associated with a better prognostic factor of PFS. Additionally, smoking habits and tumor status had a poor prognostic factor of PFS. Moreover, we found that antiangiogenic therapy has high efficacy with first-line chemotherapy and longer PFS of NSCLC patients.

Mechanisms of resistance to CAR T cell therapy

The successes with chimeric antigen receptor (CAR) T cell therapy in early clinical trials involving patients with pre-B cell acute lymphoblastic leukaemia (ALL) or B cell lymphomas have revolutionized anticancer therapy, providing a potentially curative option for patients who are refractory to standard treatments. These trials resulted in rapid FDA approvals of anti-CD19 CAR T cell products for both ALL and certain types of B cell lymphoma - the first approved gene therapies in the USA. However, growing experience with these agents has revealed that remissions will be brief in a substantial number of patients owing to poor CAR T cell persistence and/or cancer cell resistance resulting from antigen loss or modulation. Furthermore, the initial experience with CAR T cells has highlighted challenges associated with manufacturing a patient-specific therapy. Understanding the limitations of CAR T cell therapy will be critical to realizing the full potential of this novel treatment approach. Herein, we discuss the factors that can preclude durable remissions following CAR T cell therapy, with a primary focus on the resistance mechanisms that underlie disease relapse. We also provide an overview of potential strategies to overcome these obstacles in an effort to more effectively incorporate this unique therapeutic strategy into standard treatment paradigms.

CRISPR/Cas9: a powerful tool for identification of new targets for cancer treatment

Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR associated nuclease 9 (Cas9), as a powerful genome-editing tool, has revolutionized genetic engineering. It is widely used to investigate the molecular basis of different cancer types. In this review, we present an overview of recent studies in which CRISPR/Cas9 has been used for the identification of potential molecular targets. Based on the collected data, we suggest here that CRISPR/Cas9 is an effective system to distinguish between mutant and wild-type alleles in cancer. We show that several new potential therapeutic targets, such as CD38, CXCR2, MASTL, and RBX2, as well as several noncoding (nc)RNAs have been identified using CRISPR/Cas9 technology. We also discuss the obstacles and challenges that we face for using CRISPR/Cas9 as a therapeutic.

Prognostic and clinicopathological value of MUC1 expression in colorectal cancer: A meta-analysis

BACKGROUND

Accumulating evidence supports the overexpression of mucin 1 (MUC1) in colorectal cancer (CRC), but the value of elevated MUC1 expression remains controversial. Here, we evaluated the prognostic and clinicopathological value of MUC1 expression in CRC.

MATERIALS AND METHODS

The Web of Science, PubMed, Embase, Cochrane Library, and Wanfang databases, as well as the China Biology Medicine disc (CBMdisc) and China National Knowledge Infrastructure (CNKI) were searched for studies on MUC1 expression and prognosis of CRC through July 20, 2018. The pooled relative risks (RRs) and hazard ratios (HRs) with 95% confidence intervals (95% CIs) were calculated to evaluate the prognostic and clinicopathological value of MUC1 expression in CRC. The Revman version 5.3 package and STATA, version 12 were employed for pooled analysis and analysis of publication bias.

RESULTS

This meta-analysis included 16 published studies. The combined analysis showed that CRC patients with high MUC1 expression had a worse clinical outcome in overall survival (OS) (HR = 1.51, 95% CI = 1.30-1.75, P <.00001). In addition, high MUC1 expression was associated with higher TNM stage (RR = 1.44, 95% CI = 1.17-1.77, P = .0007), greater depth of invasion (RR = 1.30, 95% CI = 1.10-1.53, P = .002), and lymph node metastasis (RR = 1.47, 95% CI = 1.20-1.80, P = .0002) of CRC. However, the elevated MUC1 expression was not related to disease-free survival/recurrence-free survival (DFS/RFS) (HR = 1.51, 95% CI = 0.78-2.89, P = .22), histological grade (RR = 1.15, 95% CI = 0.96-1.38, P = .12), gender (RR = 0.95; 95% CI = 0.83-1.08, P = .44), tumor size (RR = 1.11, 95% CI = 0.85-1.44, P = .44), tumor site (RR = 1.01, 95% CI = 0.88-1.16, P = .84), or mucinous component (RR = 0.83, 95% CI = 0.60-1.14, P = .24) in CRC.

CONCLUSION

Our findings indicated that high MUC1 expression represents a marker of poor prognosis in CRC. Meanwhile, elevated MUC1 expression was associated with advanced TNM stage, greater depth of invasion, and lymph node metastasis.

Assessment of Seven Clinical Tumor Markers in Diagnosis of Non-Small-Cell Lung Cancer

Background

The correlation between tumor markers (TM) and TNM stage of non-small-cell lung cancer (NSCLC) has not been widely reported.

Methods

TM levels (CEA, CA125, CA15-3, CA19-9, CA72-4, CYFRA21-1, and SCC-Ag) in 424 cases of lung adenocarcinoma (LAC), 166 cases of lung squamous cell carcinoma (LSCC), and 103 cases of benign chest disease (BCD) were analyzed before treatment.

Results

By Kendall's tau-b correlation analysis, CEA, CA125, CA15-3, CA19-9, CA72-4, CYFRA21-1, and SCC-Ag were correlated with T stage of LAC (r = 0.235, p < 0.05; r = 0.298, p < 0.05; r = 0.254, p < 0.05; r = 0.063, p < 0.05; r = 0.080, p < 0.05; r = 0.268, p < 0.05; and r = 0.080, p < 0.05). CEA, CA125, CA15-3, CA19-9, CA72-4, and CYFRA21-1 were correlated with N stage of LAC (r = 0.356, p < 0.05; r = 0.415, p < 0.05; r = 0.340, p < 0.05; r = 0.117, p < 0.05; r = 0.175, p < 0.05; and r = 0.351, p < 0.05). CEA, CA125, CA15-3, CA19-9, CA72-4, and CYFRA21-1 were correlated with M stage of LAC (r = 0.365, p < 0.05; r = 0.353, p < 0.05; r = 0.293, p < 0.05; r = 0.135, p < 0.05; r = 0.169, p < 0.05; and r = 0.312, p < 0.05). CA125, CYFRA21-1, and SCC-Ag were correlated with T stage of LSCC (r = 0.202, p < 0.05; r = 0.233, p < 0.05; and r = 0.099, p < 0.05). CA125 and CYFRA21-1 were correlated with N stage of LSCC (r = 0.178, p < 0.05 and r = 0.284, p < 0.05). CA125, CA15-3, and CYFRA21-1 were correlated with M stage of LSCC (r = 0.214, p < 0.05; r = 0.152, p < 0.05; and r = 0.213, p < 0.05). Combining hazard ratio, AUC, sensitivity, specificity, NPV, and PPV, it was concluded that CEA and CYFRA21-1were the most related TM of LAC. SCC-Ag and CYFRA21-1 were the most related TM of LSCC.

Conclusions

CEA combined with CYFRA21-1 contributed to auxiliary diagnosis of LAC. CYFRA21-1 combined with SCC-Ag contributed to auxiliary diagnosis of LSCC. CEA, CA125, CA15-3, CA19-9, CA72-4, and CYFRA21-1 were correlated with primary tissue and metastasis of LAC. CA125 and CYFRA21-1 were correlated with primary tissue and metastasis of LSCC.

Clinical associations of mucin 1 in human lung cancer and precancerous lesions

Mucin 1 (MUC1) is a cell membrane glycoprotein overexpressed in non-small cell lung cancer (NSCLC) and has been implicated in carcinogenesis of premalignant lung lesions. Thus, MUC1 has been a target of interest for vaccine strategies for lung cancer treatment and prevention. Here, we assessed MUC1 expression by immunohistochemistry using tumor samples from patients with biopsy-proven NSCLC. Levels of expression in areas of dysplasia, metaplasia, adenocarcinoma in situ, and carcinoma within the same tissue sample were characterized independently on a scale of 0-3 for paired comparison. We also assessed clinical data for correlations with MUC1 expression. Our analysis included 16 samples from patients with squamous lesions and 19 from patients with adenocarcinoma lesions. Among squamous lesions, MUC1 expression score was significantly increased in dysplastic compared with metaplastic areas (mean difference = 0.83, 95% confidence interval [CI], 0.21-infinity; P = 0.021). MUC1 expression was also increased among areas of squamous cell carcinoma versus dysplastic areas (mean difference = 0.44, 95% CI, -0.006-infinity; P = 0.052). In the adenocarcinoma lesions, MUC1 expression was increased in adenocarcinoma versus adenocarcinoma in situ, although not significantly (mean difference = 0.20, 95% CI, -0.055-infinity; P = 0.094). The increase in MUC1 expression with the progression of premalignant lung lesions to invasive carcinoma in patients with NSCLC supports MUC1 as a possible therapeutic target for the prevention and treatment of lung cancer.

Driving CARs on the uneven road of antigen heterogeneity in solid tumors

Uniform and strong expression of CD19, a cell surface antigen, on cells of B-cell lineage is unique to hematologic malignancies. Tumor-associated antigen (TAA) targets in solid tumors exhibit heterogeneity with regards to intensity and distribution, posing a challenge for chimeric antigen receptor (CAR) T-cell therapy. Novel CAR designs, such as dual TAA-targeted CARs, tandem CARs, and switchable CARs, in conjunction with inhibitory CARs, are being investigated as means to overcome antigen heterogeneity. In addition to heterogeneity in cancer-cell antigen expression, the key determinants for antitumor responses are CAR expression levels and affinity in T cells. Herein, we review CAR T-cell therapy clinical trials for patients with lung or pancreatic cancers, and provide detailed translational strategies to overcome antigen heterogeneity.

Clinical and prognostic significance of signal transducer and activator of transcription 3 and mucin 1 in patients with non-small cell lung cancer following surgery

Signal transducer and activator of transcription 3 (STAT3) and mucin 1 (MUC1) are associated with development, progression and a poor prognosis in several types of cancer. The present study investigated the levels of STAT3 and MUC1 in patients with non-small cell lung cancer (NSCLC) following surgery. In total, 98 patients with NSCLC were enrolled into the study. STAT3, phosphorylated (p)-STAT3 and MUC1 expression in NSCLC specimens obtained from patients were investigated using immunohistochemical analysis. Enumeration results were analyzed using the χ² test or Fisher's exact probability test. Spearman's rank correlation was used to analyze correlations between STAT3, p-STAT3 and MUC1 expression. Univariate analysis was conducted using the Kaplan-Meier estimator curve method and Cox regression multivariate analysis was performed in order to determine prognostic factors. Results demonstrated that STAT3 and p-STAT3 expression was identified in 82 and 51 patients, respectively. Furthermore, the expression of MUC1 was identified in 61/98 cases (62.2%) and STAT3 expression was significantly associated with pathological tumor-node-metastasis stage (pTNM; P<0.01). p-STAT3 expression was associated with pathological type (P<0.01), pathological lymph nodes (pN; P<0.01) and pTNM (P<0.05). MUC1 expression was associated with pathological type (P<0.05), pathological tumor pT (P<0.05), pN (P<0.01) and pTNM (P<0.01). STAT3 expression was positively associated with p-STAT3 expression (P<0.05) and p-STAT3 expression was positively associated with MUC1 expression (P<0.01). Overall, the results identified that the 3-year survival rate was 56.1% and was significantly associated with the degree of differentiation (P<0.05), pT (P<0.01), pN (P<0.01), pTNM stage (P<0.01), p-STAT3 expression (P<0.01) and MUC1 expression (P<0.05). Results obtained from the Cox multivariate regression analysis demonstrated that pN and p-STAT3 expression were independent factors associated with the 3-year survival rate.

Clinical and prognostic significance of MUC1 expression in patients with esophageal squamous cell carcinoma after radical resection

BACKGROUND/AIM

To investigate the clinical and prognostic significance of MUC1 expression in patients with esophageal squamous cell carcinoma (ESCC) after radical resection.

MATERIALS AND METHODS

A total of 108 ESCC specimens were evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR) to detect MUC1 at the mRNA level and were evaluated by immunohistochemistry (IHC) to detect MUC1 at the protein level.

RESULTS

MUC1 mRNA was found in 74 cases by RT-PCR and MUC1 protein expression was found by IHC in 70 cases. Both MUC1 mRNA and protein expression correlated with pT (<0.05), pN (P < 0.01), and pTNM (<0.01). The 5-year survival rates of the patients were 39.8%. In univariate analysis, the 5-year survival rate in the ESCC patients was significantly associated with pT (P < 0.01), pN (P < 0.01), pTNM stage (P < 0.01), and MUC1 mRNA and protein expression (P < 0.05). In multivariate analysis, pN and MUC1 expression were the independent relevant factors.

CONCLUSION

MUC1 expression can become a useful marker to predict poor prognostic factors for 5-year survival rate in patients with ESCC after radical resection.

Trial watch: DNA-based vaccines for oncological indications

DNA-based vaccination is a promising approach to cancer immunotherapy. DNA-based vaccines specific for tumor-associated antigens (TAAs) are indeed relatively simple to produce, cost-efficient and well tolerated. However, the clinical efficacy of DNA-based vaccines for cancer therapy is considerably limited by central and peripheral tolerance. During the past decade, considerable efforts have been devoted to the development and characterization of novel DNA-based vaccines that would circumvent this obstacle. In this setting, particular attention has been dedicated to the route of administration, expression of modified TAAs, co-expression of immunostimulatory molecules, and co-delivery of immune checkpoint blockers. Here, we review preclinical and clinical progress on DNA-based vaccines for cancer therapy.

Upregulation of MUC1 by its novel activator 14-3-3ζ promotes tumor invasion and indicates poor prognosis in lung adenocarcinoma

Lung adenocarcinoma (LAC) is currently the predominant histological subtype of lung cancer. Despite recent advancement in targeted therapies, the average 5-year survival rate is only 15%, highlighting the need to identify previously unrecognized molecular events that propel cancer development. Herein, we showed knockdown of 14-3-3ζ suppresses cell proliferation, migration and invasion capability of A549 and H1299 cells. MUC1 was then identified as a novel target of 14-3-3ζ protein. Overexpression of MUC1 is found to induce epithelial-mesenchymal transition and promote metastasis of lung cancer cells, while knockdown of 14-3-3ζ can completely abolish the oncogenic function of MUC1.Furthermore, we unraveled a novel mechanism that 14-3-3ζ activates NF-κB signaling pathway, and therefore enhanced MUC1/NF-κB feedback loop to upregulate MUC1 expression. From a clinical point of view, we evaluated the expression of14-3-3ζ and MUC1 in GSE68465 datasets, in which high expression of14-3-3ζ and MUC1 emerged as poor prognostic factors in LAC patients. In conclusion, we provide novel evidence that 14-3-3ζ regulates MUC1 through MUC1/NF-κB feedback loop. 14-3-3ζ and MUC1 is a promising prognostic biomarker for lung cancer patients and therapeutic targeting of 14-3-3ζ and MUC1 may be a potential treatment option for patients with LAC.

MUC1 overexpression predicts worse survival in patients with non-small cell lung cancer: evidence from an updated meta-analysis

Background

Previous studies on the prognostic role of MUC1 expression in non-small cell lung cancer (NSCLC) remain controversial. We conducted a meta-analysis to appraise the clinicopathological and prognostic effect of MUC1 in NSCLC patients.

Materials and Methods

Searches of PubMed, EMBASE and CNKI (Chinese National Knowledge Infrastructure) were conducted and relevant studies were extracted. The pooled hazard ratio (HR) or odds ratio (OR) with 95% confidence intervals (CIs) were used to estimate effects. Heterogeneity among studies and publication bias were also evaluated.

Results

A total of 15 studies with 1,682 patients were included in this meta-analysis. The pooled HRs indicated that elevated MUC1 expression was associated with poorer overall survival (HR = 2.12, 95% CI: 1.47–3.05; P < 0.001) and progression-free survival (HR = 2.00, 95% CI: 1.53-2.62; P < 0.001) in patients with NSCLC. Significant associations were also found in patients treated with epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) (HR = 3.16, 95% CI: 2.21–4.52, P < 0.001) and with a platinum-based regimen (HR = 4.35, 95% CI: 2.45–7.72, P < 0.001). Additionally, MUC1 overexpression was significantly associated with performance status (OR = 2.32, 95% CI: 1.13–4.73, P = 0.021).

Conclusions

MUC1 could be a valuable biomarker of the prognoses of NSCLC patients.

MUC1-C promotes the suppressive immune microenvironment in non-small cell lung cancer

The cancer immune microenvironment is of importance for the effectiveness of immunotherapy; however, its dysregulation is poorly understood. The MUC1-C oncoprotein is aberrantly overexpressed in non-small cell lung cancer (NSCLC) and has been linked to the induction of PD-L1. The present work investigated the effects of targeting MUC1-C in an immuno-competent MUC1 transgenic (MUC1.Tg) mouse model. We show that Lewis Lung Carcinoma cells expressing MUC1-C (LLC/MUC1) exhibit upregulation of PD-L1 and suppression of interferon-γ (IFN-γ). In studies of LLC/MUC1 cells growing in vitro and as tumors in MUC1.Tg mice, treatment with the MUC1-C inhibitor, GO-203, was associated with the downregulation of PD-L1 and induction of IFN-γ. The results further demonstrate that targeting MUC1-C results in enhanced effector function of CD8+ tumor-infiltrating lymphocytes (TILs) as evidenced by increased expression of the activation marker CD69, the degranulation marker CD107α, and granzyme B. Notably, targeting MUC1-C was also associated with marked increases in TIL-mediated killing of LLC/MUC1 cells. Analysis of gene expression data sets further showed that overexpression of MUC1 in NSCLCs correlates negatively with CD8, IFNG and GZMB, and that decreases in CD8 and IFNG are associated with poor clinical outcomes. These findings in LLC/MUC1 tumors and in NSCLCs indicate that MUC1-C→PD-L1 signaling promotes the suppression of CD8+ T-cell activation and that MUC1-C is a potential target for reprogramming of the tumor microenvironment.

Molecular Pathways: Mucins and Drug Delivery in Cancer

Over the past few decades, clinical and preclinical studies have clearly demonstrated the role of mucins in tumor development. It is well established that mucins form a barrier impeding drug access to target sites, leading to cancer chemoresistance. Recently gained knowledge regarding core enzyme synthesis has opened avenues to explore the possibility of disrupting mucin synthesis to improve drug efficacy. Cancer cells exploit aberrant mucin synthesis to efficiently mask the epithelial cells and ensure survival under hostile tumor microenvironment conditions. However, O-glycan synthesis enzyme core 2 beta 1,6 N-acetylglucosaminyltransferase (GCNT3/C2GnT-2) is overexpressed in Kras-driven mouse and human cancer, and inhibition of GCNT3 has been shown to disrupt mucin synthesis. This previously unrecognized developmental pathway might be responsible for aberrant mucin biosynthesis and chemoresistance. In this Molecular Pathways article, we briefly discuss the potential role of mucin synthesis in cancers, ways to improve drug delivery and disrupt mucin mesh to overcome chemoresistance by targeting mucin synthesis, and the unique opportunity to target the GCNT3 pathway for the prevention and treatment of cancers. Clin Cancer Res; 23(6); 1373-8. ©2016 AACR.

MUC1-C integrates PD-L1 induction with repression of immune effectors in non-small-cell lung cancer

Immunotherapeutic approaches, particularly PD-1/PD-L1 blockade, have improved the treatment of non-small cell lung cancer (NSCLC), supporting the premise that evasion of immune destruction is of importance for NSCLC progression. However, the signals responsible for upregulation of PD-L1 in NSCLC cells and whether they are integrated with the regulation of other immune-related genes are not known. Mucin 1 (MUC1) is aberrantly overexpressed in NSCLC, activates the NF-κB p65→ZEB1 pathway and confers a poor prognosis. The present studies demonstrate that MUC1-C activates PD-L1 expression in NSCLC cells. We show that MUC1-C increases NF-κB p65 occupancy on the CD274/PD-L1 promoter and thereby drives CD274 transcription. Moreover, we demonstrate that MUC1-C-induced activation of NF-κB→ZEB1 signaling represses the TLR9, IFNG, MCP-1 and GM-CSF genes, and that this signature is associated with decreases in overall survival. In concert with these results, targeting MUC1-C in NSCLC tumors suppresses PD-L1 and induces these effectors of innate and adaptive immunity. These findings support a previously unrecognized central role for MUC1-C in integrating PD-L1 activation with suppression of immune effectors and poor clinical outcome.

Abrogation of MUC5AC Expression Contributes to the Apoptosis and Cell Cycle Arrest of Colon Cancer Cells

Deregulated expressions of mucins have been found in various malignancies and play a pivotal role in carcinogenesis. MUC5AC, as a secreted mucin, is reported to be aberrantly expressed during epithelial cancer progression, including colon cancer. However, the mechanisms of the oncoprotein MUC5AC in the initiation of colon cancer requires further investigation. Here, we collected colon cancer tissues (n = 20) and corresponding paracancerous tissues (n = 20) and found that the expression of MUC5AC was significantly elevated in colon cancer tissues when compared with the corresponding paracancerous tissues. Immunofluorescence indicated that all colon cancer cell lines, including HT29, SW620, and the normal human intestinal epithelial cells FHC, showed the positive expression of MUC5AC, and SW620 exhibited the highest expression. Moreover, knockdown of MUC5AC in SW620 cells remarkably suppressed cell vitality and promoted apoptosis and G1 cell cycle arrest, resulting in the impaired ability of colony formation. Furthermore, the inhibition of MUC5AC in SW620 cells dramatically repressed the cell migration and invasion. These results demonstrated that MUC5AC as an oncogene could be a promising target in the treatment of colon cancer.

PSCA and MUC1 in non-small-cell lung cancer as targets of chimeric antigen receptor T cells

In recent years, immunotherapies, such as those involving chimeric antigen receptor (CAR) T cells, have become increasingly promising approaches to non-small-cell lung cancer (NSCLC) treatment. In this study, we explored the antitumor potential of prostate stem cell antigen (PSCA)-redirected CAR T and mucin 1 (MUC1)-redirected CAR T cells in tumor models of NSCLC. First, we generated patient-derived xenograft (PDX) mouse models of human NSCLC that maintained the antigenic profiles of primary tumors. Next, we demonstrated the expression of PSCA and MUC1 in NSCLC, followed by the generation and confirmation of the specificity and efficacy of PSCA- and MUC1-targeting CAR T cells against NSCLC cell lines in vitro. Finally, we demonstrated that PSCA-targeting CAR T cells could efficiently suppress NSCLC tumor growth in PDX mice and synergistically eliminate PSCA⁺MUC1⁺ tumors when combined with MUC1-targeting CAR T cells. Taken together, our studies demonstrate that PSCA and MUC1 are both promising CAR T cell targets in NSCLC and that the combinatorial targeting of these antigens could further enhance the antitumor efficacy of CAR T cells.

Mucin-1 correlates with survival, smoking status, and growth patterns in lung adenocarcinoma

Mucin-1 (MUC1) affects cancer progression in lung adenocarcinoma, and its aberrant expression pattern has been correlated with poor tumor differentiation and impaired prognosis. In this study, the immunohistochemical expression of MUC1 and Mucin-4 (MUC4) was analyzed in a series of 106 surgically operated stage I-IV pulmonary adenocarcinomas. MUC1 immunohistochemistry was evaluated according to the Nagai classification, and the immunohistochemical profile of the tumors was correlated with detailed clinical and histological data. The effect of cigarette smoke on MUC1 expression in lung cancer cell lines was examined using real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) and immunoelectron microscopy (IEM). In contrast to the normal apical localization of MUC1, a basolateral and cytoplasmic (depolarized) MUC1 expression pattern was frequently encountered in the high-grade subtypes, i.e., solid predominant adenocarcinoma and the cribriform variant of acinar predominant adenocarcinoma (p < 0.001), and was rarely observed in tumors containing a non-predominant lepidic component (p < 0.001). Furthermore, the altered staining pattern of MUC1 correlated with stage (p = 0.002), reduced overall survival (p = 0.031), and was associated with smoking (p < 0.001). When H1650 adenocarcinoma cells were exposed to cigarette smoke and analyzed by RT-qPCR and IEM, the levels of the MUC1 transcript and protein were elevated (p = 0.042). In conclusion, MUC1 participates in the pathogenesis of lung adenocarcinoma and associates with smoking both in vitro and in vivo. In lung adenocarcinoma, depolarized MUC1 protein expression correlated with histological growth patterns, stage, and patient outcome.

TG4010: a vaccine with a therapeutic role in cancer

One of the strategies to enhance immune response against tumors has been the use of vaccines against tumor-associated antigens (TAAs). MUC1 is a TAA that is overexpressed in many malignancies being linked to worse prognosis. Moreover, tumor MUC1 is hypoglycosylated revealing new epitopes that are antigenic and potential T-cell targets. TG4010 is a recombinant viral vaccine targeting MUC1, also encoding for IL-2. TG4010 has been tested in Phase I-II trials demonstrating a consistent safety profile with mild local reactions as main side effect. These studies have confirmed immune responses to the vaccine product. Clinical efficacy has been observed mainly in patients with non-small-cell lung cancer in combination with chemotherapy. Peripheral activated NK cells are currently being validated as biomarkers of response.

Inhibition of MUC1-C Suppresses MYC Expression and Attenuates Malignant Growth in KRAS Mutant Lung Adenocarcinomas

Dysregulation of MYC expression is a hallmark of cancer, but the development of agents that target MYC has remained challenging. The oncogenic MUC1-C transmembrane protein is, like MYC, aberrantly expressed in diverse human cancers. The present studies demonstrate that MUC1-C induces MYC expression in KRAS mutant non-small cell lung cancer (NSCLC) cells, an effect that can be suppressed by targeting MUC1-C via shRNA silencing, CRISPR editing, or pharmacologic inhibition with GO-203. MUC1-C activated the WNT/β-catenin (CTNNB1) pathway and promoted occupancy of MUC1-C/β-catenin/TCF4 complexes on the MYC promoter. MUC1-C also promoted the recruitment of the p300 histone acetylase (EP300) and, in turn, induced histone H3 acetylation and activation of MYC gene transcription. We also show that targeting MUC1-C decreased the expression of key MYC target genes essential for the growth and survival of NSCLC cells, such as TERT and CDK4. Based on these results, we found that the combination of GO-203 and the BET bromodomain inhibitor JQ1, which targets MYC transcription, synergistically suppressed MYC expression and cell survival in vitro as well as tumor xenograft growth. Furthermore, MUC1 expression significantly correlated with that of MYC and its target genes in human KRAS mutant NSCLC tumors. Taken together, these findings suggest a therapeutic approach for targeting MYC-dependent cancers and provide the framework for the ongoing clinical studies addressing the efficacy of MUC1-C inhibition in solid tumors.

Mucin 1-mediated chemo-resistance in lung cancer cells

Paclitaxel (PTX) is a commonly used drug to treat diverse cancer types. However, its treatment can generate resistance and the mechanisms of PTX-resistance in lung cancers are still unclear. We demonstrated that non-small cell lung cancers (NSCLCs) survive PTX treatment. Compared with the progenitor NSCLC A549 cells, the PTX-resistant A549 cells (A549/PTX) displayed enhanced sphere-formation ability. The proportion of the cancer stem cell marker, aldehyde dehydrogenase-positive cells, and epithelial-mesenchymal transition signaling protein levels were also elevated in A549/PTX. Importantly, the levels of oncoproteins phosphoinositide-3 kinase/Akt, mucin 1 cytoplasmic domain (MUC1-C) and β-catenin were also significantly elevated in A549/PTX. Furthermore, nuclear translocation of MUC1-C and β-catenin increased in A549/PTX. The c-SRC protein, an activator of MUC1-C, was also overexpressed in A549/PTX. These observations led to the hypothesis that enhanced expression of MUC1-C is associated with stemness and PTX resistance in NSCLCs. To test this, we knocked down or overexpressed MUC1-C in A549/PTX and found that inhibition of MUC1-C expression coupled with PTX treatment was sufficient to reduce the sphere-forming ability and survival of A549/PTX. In summary, our in vitro and in vivo studies have revealed a potential mechanism of MUC1-C-mediated PTX resistance and provided insights into a novel therapeutic measure for lung cancers.

Mucins in lung cancer: diagnostic, prognostic, and therapeutic implications

Aberrant expression of mucins is associated with cancer development and metastasis. An overexpression of few mucins contributes to oncogenesis by enhancing cancer cell growth and providing constitutive survival signals. This review focuses on the importance of mucins both in the normal bronchial epithelial cells and the malignant tumors of the lung and their contribution in the diagnosis and prognosis of lung cancer patients. During lung cancer progression, mucins either alone or through their interaction with many receptor tyrosine kinases mediate cell signals for growth and survival of cancer cells. Also, stage-specific expression of certain mucins, like MUC1, is associated with poor prognosis from lung cancer. Thus, mucins are emerging as attractive targets for developing novel therapeutic approaches for lung cancer. Several strategies targeting mucin expression and function are currently being investigated to control lung cancer progression.

Expression of secreted phospholipase A2-Group IIA correlates with prognosis of gastric adenocarcinoma

The present study investigated the expression of secretory phospholipase A2-Group IIA (sPLA2-II) in gastric adenocarcinoma, in order to evaluate the correlation between sPLA2-II expression, and the clinicopathological features and prognosis of patients with gastric adenocarcinoma. Between January 2007 and April 2010, data were collected from 65 patients (44 males, 21 females; age range, 30-79 years; mean 66.7 ± 10.7 years). All patients exhibited a pathologically confirmed diagnosis of gastric adenocarcinoma. Endoscopic biopsy specimens of normal gastric mucosa from 11 of these patients were used as controls. Patients were subsequently followed-up at 3-month intervals, and survival data were recorded until April 2010. Expression of sPLA2-II in 65 gastric adenocarcinoma and 11 normal gastric mucosa specimens was evaluated via immunohistochemistry. A semi-quantitative method, consisting of evaluation of staining percentage and intensity, was utilized for immunohistochemical scoring, and the receiver operating characteristic curve method was applied to select a cut-off score for high and low sPLA2-II expression. The value of 8 was selected as the cut-off score, with maximum sensitivity and specificity. High sPLA2-II expression was observed in stage III/IV cases (83.3%; 40/48) and poorly differentiated cells (94.1%; 32/34), while sPLA2-II expression levels were observed to be significantly lower in stage I/II cases (52.9%; 9/17) and well and moderately differentiated cells (54.8%; 17/31; P=0.021 and P<0.001, respectively). There were no significant correlations observed between sPLA2-II expression and any other clinicopathological parameters, including gender, age, tumor diameter and Helicobacter pylori infection. Patients exhibiting low sPLA2-II expression experienced significantly improved overall survival (OS) and disease-free survival (DFS), compared with those exhibiting high sPLA2-II expression (P=0.043 and P=0.035, respectively). Multivariate analysis confirmed that high sPLA2-II expression may be an independent prognostic factor for OS [relative risk, 2.849; 95% confidence interval (CI), 1.088-7.459; P=0.033] and DFS (relative risk, 2.735; 95% CI, 1.104-6.776; P=0.030) in gastric adenocarcinoma. Therefore, sPLA2-II may be correlated with the histogenesis of gastric adenocarcinoma, and increased sPLA2-II expression may be an indicator of poor prognosis.

MUC1-C confers EMT and KRAS independence in mutant KRAS lung cancer cells

Non-small cell lung cancers (NSCLCs) that harbor an oncogenic KRAS mutation are often associated with resistance to targeted therapies. The MUC1-C transmembrane protein is aberrantly overexpressed in NSCLCs and confers a poor outcome; however, the functional role for MUC1-C in mutant KRAS NSCLC cells has remained unclear. The present studies demonstrate that silencing MUC1-C in A549/KRAS(G12S) and H460/KRAS(Q61H) NSCLC cells is associated with downregulation of AKT signaling and inhibition of growth. Overexpression of a MUC1-C(CQC→AQA) mutant, which inhibits MUC1-C homodimerization and function, suppressed both AKT and MEK activation. Moreover, treatment with GO-203, an inhibitor of MUC1-C homodimerization, blocked AKT and MEK signaling and decreased cell survival. The results further demonstrate that targeting MUC1-C suppresses expression of the ZEB1 transcriptional repressor by an AKT-mediated mechanism, and in turn induces miR-200c. In concert with these effects on the ZEB1/miR-200c regulatory loop, targeting MUC1-C was associated with reversal of the epithelial-mesenchymal transition (EMT) and inhibition of self-renewal capacity. Loss of MUC1-C function also attenuated KRAS independence and inhibited growth of KRAS mutant NSCLC cells as tumors in mice. These findings support a model in which targeting MUC1-C inhibits mutant KRAS signaling in NSCLC cells and thereby reverses the EMT phenotype and decreases self-renewal.

Tecemotide in unresectable stage III non-small-cell lung cancer in the phase III START study: updated overall survival and biomarker analyses

BACKGROUND

Tecemotide is a MUC1-antigen-specific cancer immunotherapy. The phase III START study did not meet its primary end point but reported notable survival benefit with tecemotide versus placebo in an exploratory analysis of the predefined patient subgroup treated with concurrent chemoradiotherapy. Here, we attempted to gain further insight into the effects of tecemotide in START.

PATIENTS AND METHODS

START recruited patients who did not progress following frontline chemoradiotherapy for unresectable stage III non-small-cell lung cancer. We present updated overall survival (OS) data and exploratory analyses of OS for baseline biomarkers: soluble MUC1 (sMUC1), antinuclear antibodies (ANA), neutrophil/lymphocyte ratio (NLR), lymphocyte count, and HLA type.

RESULTS

Updated OS data are consistent with the primary analysis: median 25.8 months (tecemotide) versus 22.4 months (placebo) (HR 0.89, 95% CI 0.77-1.03, P = 0.111), with ∼20 months additional median follow-up time compared with the primary analysis. Exploratory analysis of the predefined subgroup treated with concurrent chemoradiotherapy revealed clinically relevant prolonged OS with tecemotide versus placebo (29.4 versus 20.8 months; HR 0.81, 95% CI 0.68-0.98, P = 0.026). No improvement was seen with sequential chemoradiotherapy. High sMUC1 and ANA correlated with a possible survival benefit with tecemotide (interaction P = 0.0085 and 0.0022) and might have future value as biomarkers. Interactions between lymphocyte count, NLR, or prespecified HLA alleles and treatment effect were not observed.

CONCLUSION

Updated OS data support potential treatment benefit with tecemotide in patients treated with concurrent chemoradiotherapy. Exploratory biomarker analyses suggest that elevated sMUC1 or ANA levels correlate with tecemotide benefit.

CLINICALTRIALSGOV NUMBER

NCT00409188.

The future of immunotherapy in the treatment of lung cancer

SUMMARY 

Despite advances in the understanding of the genetic and nongenetic mechanisms involved in driving the development of lung cancers, mortality from lung cancer remains very poor. Detection and recognition of pathogens as being foreign and the facilitation of their destruction is the fundamental role of the immune system. Recent approval for the use of immunotherapeutics in the treatment of melanoma and prostate cancer, and emerging evidence of the interplay between malignant cells and the host immune response in recognizing them have led to a new focus in the treatment of lung cancer. Such strategies include vaccination therapies and immune checkpoint blockade, many of which have reached Phase III trials but with modest translation to clinical benefit. This article looks at the biology and current clinical data in the use of these immunological agents.

L-BLP25 as a peptide vaccine therapy in non-small cell lung cancer: a review

Lung cancer is one of the most prevalent malignancies worldwide and the leading cause of cancer-related death. Most cases are non-small cell lung cancer (NSCLC). The median overall survival of patients with advanced stage undergoing current standard chemotherapy is approximately 10 months. The addition of new compounds, including targeted agents, to standard first-line cytotoxic doublets, which are administered concurrently and/or as maintenance therapy in patients who have not experienced disease progression after first-line treatment, has shown potential in improving the efficacy in patients with advanced disease. L-BLP25 is a mucin 1 (MUC1) antigen-specific immunotherapy induces a T-cell response to MUC1 in both a preclinical MUC1-transgenic lung cancer mouse model and patients. This review is aimed at introducing the mechanism by which L-BLP25 targets MUC1, summarizing the achievements gained in the completed clinical trials with L-BLP25 administered as maintenance therapy in the treatment of unresectable stage III/IV NSCLC, and discussing the research trends.

Pivotal role of MUC1 glycosylation by cigarette smoke in modulating disruption of airway adherens junctions in vitro

Cigarette smoke increases the risk of lung cancer by 20-fold and accounts for 87% of lung cancer deaths. In the normal airway, heavily O-glycosylated mucin-1 (MUC1) and adherens junctions (AJs) establish a structural barrier that protects the airway from infectious, inflammatory and noxious stimuli. Smoke disrupts cell-cell adhesion via its damaging effects on the AJ protein epithelial cadherin (E-cad). Loss of E-cad is a major hallmark of epithelial-mesenchymal transition (EMT) and has been reported in lung cancer, where it is associated with invasion, metastasis and poor prognosis. Using organotypic cultures of primary human bronchial epithelial (HBE) cells treated with smoke-concentrated medium (Smk), we have demonstrated that E-cad loss is regulated through the aberrant interaction of its AJ binding partner, p120-catenin (p120ctn), and the C-terminus of MUC1 (MUC1-C). Here, we reported that even before MUC1-C became bound to p120ctn, smoke promoted the generation of a novel 400 kDa glycoform of MUC1's N-terminus (MUC1-N) differing from the 230 kDa and 150 kDa glycoforms in untreated control cells. The subsequent smoke-induced, time-dependent shedding of glycosylated MUC1-N exposed MUC1-C as a putative receptor for interactions with EGFR, Src and p120ctn. Smoke-induced MUC1-C glycosylation modulated MUC1-C tyrosine phosphorylation (TyrP) that was essential for MUC1-C/p120ctn interaction through dose-dependent bridging of Src/MUC1-C/galectin-3/EGFR signalosomes. Chemical deglycosylation of MUC1 using a mixture of N-glycosylation inhibitor tunicamycin and O-glycosylation inhibitor benzyl-α-GalNAc disrupted the Src/MUC1-C/galectin-3/EGFR complexes and thereby abolished smoke-induced MUC1-C-TyrP and MUC1-C/p120ctn interaction. Similarly, inhibition of smoke-induced MUC1-N glycosylation using adenoviral shRNA directed against N-acetyl-galactosaminyl transferase-6 (GALNT6, an enzyme that controls the initiating step of O-glycosylation) successfully suppressed MUC1-C/p120ctn interaction, prevented E-cad degradation and maintained cellular polarity in response to smoke. Thus, GALNT6 shRNA represents a potential therapeutic modality to prevent the initiation of events associated with EMT in the smoker's airway.

Current clinical immunotherapy targets in advanced nonsmall cell lung cancer (NSCLC)

NSCLC remains one of the most challenging malignancies to treat. Despite the introduction of innovative therapies over the last decade, the 5-year survival of NSCLC is still <20%. Clearly, novel, therapeutic approaches are required. Targeting the immune system to derive meaningful clinical benefit has proved successful in various malignancies in recent years. As a result, there is renewed focus on the use of immunotherapy in lung cancer. In this review, we provide an overview of current immune-modulatory approaches in the treatment of NSCLC.

Cigarette smoke disrupts the integrity of airway adherens junctions through the aberrant interaction of p120-catenin with the cytoplasmic tail of MUC1

Adherens junctions (AJs) containing epithelial cadherin (E-cad) bound to p120-catenin (p120ctn) and β-catenin (β-ctn) play a crucial role in regulating cell-cell adhesion. Cigarette smoke abrogates cell-cell adhesion between epithelial cells by disrupting E-cad, a hallmark of epithelial-mesenchymal transition (EMT), yet the underlying mechanism remains unknown. We used an organotypic culture of primary human bronchial epithelial (HBE) cells treated with smoke-concentrated medium (Smk) to establish an essential role for the interaction between p120ctn and the cytoplasmic tail of MUC1 (MUC1-CT) in regulating E-cad disruption. Within the first 4 h of smoke exposure, apical MUC1-CT repositioned to the basolateral membrane of pseudo-stratified HBE cells, where it interacted with p120ctn. A time-dependent increase in MUC1-CT/p120ctn complexes occurred in conjunction with a time-dependent dissociation of p120ctn/E-cad/β-ctn complexes, as well as the coordinated degradation of p120ctn and E-cad. Interestingly, Smk induced a similar interaction between MUC1-CT and β-ctn, but this occurred 44 h after MUC1-CT's initial interaction with p120ctn, and well after the AJs were destroyed. Blocking MUC1-CT's interaction with p120ctn using a MUC1-CT dominant-negative peptide, PMIP, successfully abolished Smk's disruptive effects on AJs and recovered apical-basolateral polarity of HBE cells. The MUC1-CT/p120ctn interaction was highly dependent on EGFR/Src/Jnk-mediated tyrosine phosphorylation (TyrP) of MUC1-CT. Accordingly, EGFR, Src or Jnk inhibitors (AG1478, PP2, SP600125, respectively) abrogated Smk-induced MUC1-CT-TyrP, MUC1-CT/p120ctn interaction, AJ disruption, and loss of cellular polarity. Our work identified MUC1-CT and p120ctn as important regulators of epithelial polarity and cell-cell adhesion during a smoke-induced EMT-like process. Novel therapeutics designed to inhibit MUC1-CT/p120ctn complex formation may prevent EMT in the smoker's airway.

Depolarized MUC1 Expression Is Closely Associated With Hypoxic Markers and Poor Outcome in Resected Non–Small Cell Lung Cancer

MUC1 is transmembrane mucin aberrantly overexpressed in various cancers. However, little is known about how MUC1 expression is associated with hypoxia, glucose metabolism, and epidermal growth factor receptor (EGFR) pathway, which are related to cancer progression. The aim of this study is to evaluate the relationship between MUC1 expression and these molecular markers in lung cancer. Of all 126 patients, high-grade polarized expression (HP), low-grade polarized expression (LP), and depolarized expression (DP) group were 50 (39.7%), 35 (27.8%), and 41 (32.5%), respectively. Depolarized MUC1 expression was significantly associated with poor outcome and was closely correlated with glucose metabolism (Glut1), hypoxia (HIF-1α), angiogenesis (vascular endothelial growth factor and microvessel density), amino acid metabolism (LAT1), and EGFR expression. High-grade polarized MUC1 expression was associated with favorable prognosis and adenocarcinoma. Depolarized MUC1 expression was significantly associated with poor outcome. Glucose metabolism, hypoxia, angiogenesis, amino acid metabolism, and EGFR pathway may play an important role in the development of depolarized MUC1 expression.

Overexpression of MUC1 enhances proangiogenic activity of non-small-cell lung cancer cells through activation of Akt and extracellular signal-regulated kinase pathways

BACKGROUND

Angiogenesis is an important process required for tumor progression. Mucin 1 (MUC1) is a transmembrane glycoprotein that is aberrantly upregulated in many types of cancer, including non-small-cell lung cancer (NSCLC). However, the biological significance of MUC1 overexpression in lung cancer angiogenesis is not completely understood.

METHODS

We showed that enforced expression of MUC1 in two NSCLC cell lines, A549 and NCI-H460, which have a low level of endogenous MUC1, promoted their ability to induce vascular endothelial growth factor (VEGF)-dependent endothelial cell migration and tube formation.

RESULTS

There was a significant increase in VEGF expression in MUC1-overexpressing NSCLC cells. Moreover, MUC1 overexpression resulted in a marked elevation in phosphorylated Akt and extracellular signal-regulated kinase (ERK)1/2, indicative of activation of both signaling pathways. Most importantly, inhibition of Akt or ERK signaling using specific chemical inhibitors restrained the proangiogenic activity of MUC1-overexpressing NSCLC cells.

CONCLUSIONS

Taken together, our present data demonstrate that the aberrant upregulation of MUC1 favors tumor angiogenesis in NSCLC, likely through the activation of both Akt and ERK pathways and elevation of VEGF production. MUC1 may thus be a potential antiangiogenic target in NSCLC.