MAGE-A antigens as targets in tumour therapy

Magea13 attenuates myocardial injury in acute myocardial infarction by inhibiting the cAMP-PKA signaling pathway

OBJECT

Acute myocardial infarction (AMI) is a serious cardiovascular disease for which there are still no effective therapeutic options available, and melanoma-associated antigen-A13 (Magea13), a member of the MAGE superfamily, has an unknown role in AMI. This study aims to investigate the potential role and molecular mechanisms of Magea13 in myocardial injury associated with AMI through in vivo and in vitro experiments.

METHODS

Firstly, differentially expressed genes (DEGs) and signaling pathways were screened by RNA sequencing. Cardiac-specific Magea13 overexpression was achieved with the adeno-associated virus type 9 serotype system. Subsequently, these rats underwent left anterior descending coronary artery (LAD) ligation, followed by histopathological examination, biochemical assay, and Western blot analysis to evaluate the efficacy and feasibility of Magea13 in AMI. Meanwhile, the Magea13-overexpressing rat cardiomyocyte cell line (H9c2) was also subjected to hypoxia-glucose deficiency/reperfusion to mimic AMI injury to further validate its effects in vitro.

RESULTS

The cardiomyocyte-specific overexpression of Magea13 was observed to attenuate myocardial injury in rats with acute myocardial infarction. Furthermore, Magea13 overexpression was demonstrated to attenuate OGD/R-induced H9c2 cell injury. Mechanistic studies have suggested that the protective effect of Magea13 may be mediated through the cAMP-PKA pathway.

CONCLUSION

Magea13 has been demonstrated to offer protection against AMI myocardial injury through the cAMP-PKA signaling pathway and is therefore a promising therapeutic and predictive target for AMI myocardial injury.

Overexpression of MAGE-A2 is Related to the Malignant Degree and Progression of Disease in Patients With Clear Cell Renal Cell Carcinoma

Melanoma antigen gene-A2 (MAGE-A2) is one of the most cancer-testis antigens overexpressed in a variety of malignancies. However, the expression of MAGE-A2 for clinical values in the pathophysiology of renal cell carcinoma (RCC) is unknown. For the first time, the present study was conducted to examine the expression and prognostic significance of MAGE-A2 expression in clear cell RCC (ccRCC). MAGE-A2 expression was assayed in 162 well-defined ccRCC samples using immunohistochemistry staining on tissue microarrays. The association between MAGE-A2 expression and clinic-pathologic features as well as survival outcomes were then performed. A significant and positive correlation was found between cytoplasmic expression of MAGE-A2 with tumor size ( P =0.008), nucleolar grade ( P =0.001), tumor stage ( P =0.001), microvascular invasion ( P =0.001), invasion to renal pelvis ( P =0.032), renal sinus fat ( P =0.004), and Gerota's fascia ( P =0.028) as well as histologic tumor necrosis ( P <0.0001). Increased expression of MAGE-A2 was observed to be associated with shorter progression-free survival (PFS) compared with patients with low expression of MAGE-A2 ( P =0.032). Multivariate analysis revealed that tumor size and nucleolar grade are independent predictors of the PFS ( P =0.054, P =0.032, respectively). Our results indicated that increased cytoplasmic expression of MAGE-A2 is associated with the malignant degree and progression of ccRCC. This data improved the significance of MAGE-A2 expression and will potentially allow using MAGE-A2 for the prognosis of the disease and immunotherapy in patients with ccRCC.

Drug Delivery Opportunities in Esophageal Cancer: Current Treatments and Future Prospects

With one of the highest mortality rates of all malignancies, the 5-year survival rate for esophageal cancer is under 20%. Depending on the stage and extent of the disease, the current standard of care treatment paradigm includes chemotherapy or chemoradiotherapy followed by surgical esophagogastrectomy, with consideration for adjuvant immunotherapy for residual disease. This regimen has high morbidity, due to anatomic changes inherent in surgery, the acuity of surgical complications, and off-target effects of systemic chemotherapy and immunotherapy. We begin with a review of current treatments, then discuss new and emerging targets for therapies and advanced drug delivery systems. Recent and ongoing preclinical and early clinical studies are evaluating traditional tumor targets (e.g., human epidermal growth factor receptor 2), as well as promising new targets such as Yes-associated protein 1 or mammalian target of rapamycin to develop new treatments for this disease. Due the function and location of the esophagus, opportunities also exist to pair these treatments with a drug delivery strategy to increase tumor targeting, bioavailability, and intratumor concentrations, with the two most common delivery platforms being stents and nanoparticles. Finally, early results with antibody drug conjugates and chimeric antigenic receptor T cells show promise as upcoming therapies. This review discusses these innovations in therapeutics and drug delivery in the context of their successes and failures, with the goal of identifying those solutions that demonstrate the most promise to shift the paradigm in treating this deadly disease.

MAGE-A11 is a potential prognostic biomarker and immunotherapeutic target in gastric cancer

Gastric cancer poses a serious threat to human health and affects the digestive system. The lack of early symptoms and a dearth of effective identification methods make diagnosis difficult, with many patients only receiving a definitive diagnosis at a malignant stage, causing them to miss out on optimal therapeutic interventions. Melanoma-associated antigen-A (MAGE-A) is part of the MAGE family and falls under the cancer/testis antigen (CTA) category. The MAGE-A subfamily plays a significant role in tumorigenesis, proliferation and migration. The expression, prognosis and function of MAGE-A family members in GC, however, remain unclear. Our research and screening have shown that MAGE-A11 was highly expressed in GC tissues and was associated with poor patient prognosis. Additionally, MAGE-A11 functioned as an independent prognostic factor in GC through Cox regression analysis, and its expression showed significant correlation with both tumour immune cell infiltration and responsiveness to immunotherapy. Our data further indicated that MAGE-A11 regulated GC cell proliferation and migration. Subsequently, our findings propose that MAGE-A11 may operate as a prognostic factor, having potential as an immunotherapy target for GC.

Immunization with a multi-antigen targeted DNA vaccine eliminates chemoresistant pancreatic cancer by disrupting tumor-stromal cell crosstalk

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is characterised by limited responses to chemoimmunotherapy attributed to highly desmoplastic tumor microenvironment. Disrupting the tumor-stromal cell crosstalk is considered as an improved PDAC treatment strategy, whereas little progress has been made due to poor understanding of its underlying mechanism. Here, we examined the cellular role of melanoma associated antigen A isoforms (MAGEA) in regulating tumor-stromal crosstalk mediated chemoresistance.

METHODS

We used clinical samples to explore the correlation between MAGEA expression and patient prognosis in multiple cancers. We utilized cancer cell lines, patient derived organoids and orthotopic PDAC model to examine the function of MAGEA in chemoresistance. We performed biochemical, proteome profiler array and transcriptional analysis to uncover a mechanism that governs tumor-stromal crosstalk. We developed a multi-MAGEA antigen targeted DNA vaccine and tested its effect on PDAC tumor growth.

RESULTS

We establish MAGEA as a regulator of the tumor-stromal crosstalk in PDAC. We provide strong clinical evidence indicating that high MAGEA expression, including MAGEA2, MAGEA3 and MAGEA10, correlates with worse chemotherapeutic response and poor prognosis in multiple cancers, while their expression is up-regulated in chemoresistant PDAC patient derived organoids and cancer cell lines. Mechanistically, MAGEA2 prohibits gemcitabine-induced JNK-c-Jun-p53 mediated cancer cell apoptosis, while gemcitabine stimulated pancreatic stellate cells secretes GDF15 to further enhance the gemcitabine resistance of MAGEA2 expressing cells by activating GFRAL-RET mediated Akt and ERK1/2 dependent survival pathway. Strikingly, immunization with a DNA vaccine that targeting multiple MAGEA antigens, including MAGEA2, MAGEA3 and MAGEA10, elicits robust immune responses against the growth of gemcitabine resistant tumors.

CONCLUSIONS

These findings suggest that targeting MAGEA-mediated paracrine regulation of chemoresistance by immunotherapy can be an improved pancreatic cancer treatment strategy.

MAGEA6 positively regulates MSMO1 and promotes the migration and invasion of oesophageal cancer cells

The melanoma antigen gene family A (MAGEA) family of proteins comprises of cancer-testis antigens that are highly expressed in a number of tumours but are minimally expressed in normal cells. Due to its expression characteristics, this protein family has become a popular target for anti-cancer drugs and immunotherapy research over recent years. Although, elevated expression levels of MAGEA6 has been found in different types of tumours, there remains to be insufficient information on the function of MAGEA6 and its associated gene regulation pathways. The present study used Transwell, Cell Counting Kit-8 and wound healing assays to analyse the effects of MAGEA6 on Eca109 cell invasion, migration and proliferation. The main functions and pathways involved in MAGEA6 were predicted by Illumina Hiseq screening for mutually regulated genes and core genes. Eca109 cell line with a high expression of MAGEA6 was a stable cell line obtained by transfection in the early stage, and this cell line was used in subsequent experiments. Transcriptome sequencing was performed on this cell line and the Eca109 cell line that normally expressed MAGEA6. It was revealed that a high expression of MAGEA6 conferred a significant stimulating effect on cell proliferation whilst also significantly increasing cell invasion and migration. Transcriptomic analysis identified 14 differentially expressed genes and 13 core regulatory genes closely associated with MAGEA6 expression regulation, such as methylsterol monooxygenase 1 (MSMO1). The present study suggest that MAGEA6 positively regulated MSMO1 expression, which may serve an oncogenic role in cells through this regulatory effect. Overall, this provided a novel route of investigation for an in-depth study of the regulatory function of MAGEA6.

MAGEA4 Coated Extracellular Vesicles Are Stable and Can Be Assembled In Vitro

Extracellular vesicles (EVs) are valued candidates for the development of new tools for medical applications. Vesicles carrying melanoma-associated antigen A (MAGEA) proteins, a subfamily of cancer-testis antigens, are particularly promising tools in the fight against cancer. Here, we have studied the biophysical and chemical properties of MAGEA4-EVs and show that they are stable under common storage conditions such as keeping at +4 °C and -80 °C for at least 3 weeks after purification. The MAGEA4-EVs can be freeze-thawed two times without losing MAGEA4 in detectable quantities. The attachment of MAGEA4 to the surface of EVs cannot be disrupted by high salt concentrations or chelators, but the vesicles are sensitive to high pH. The MAGEA4 protein can bind to the surface of EVs in vitro, using robust passive incubation. In addition, EVs can be loaded with recombinant proteins fused to the MAGEA4 open reading frame within the cells and also in vitro. The high stability of MAGEA4-EVs ensures their potential for the development of EV-based anti-cancer applications.

Expression of the tumor-expressed protein MageB2 enhances rRNA transcription

An essential requirement for cells to sustain a high proliferating rate is to be paired with enhanced protein synthesis through the production of ribosomes. For this reason, part of the growth-factor signaling pathways, are devoted to activate ribosome biogenesis. Enhanced production of ribosomes is a hallmark in cancer cells, which is boosted by different mechanisms. Here we report that the nucleolar tumor-protein MageB2, whose expression is associated with cell proliferation, also participates in ribosome biogenesis. Studies carried out in both siRNA-mediated MageB2 silenced cells and CRISPR/CAS9-mediated MageB2 knockout (KO) cells showed that its expression is linked to rRNA transcription increase independently of the cell proliferation status. Mechanistically, MageB2 interacts with phospho-UBF, a protein which causes the recruitment of RNA Pol I pre-initiation complex required for rRNA transcription. In addition, cells expressing MageB2 displays enhanced phospho-UBF occupancy at the rDNA gene promoter. Proteomic studies performed in MageB2 KO cells revealed impairment in ribosomal protein (RPs) content. Functionally, enhancement in rRNA production in MageB2 expressing cells, was directly associated with an increased dynamic in protein synthesis. Altogether our results unveil a novel function for a tumor-expressed protein from the MAGE-I family. Findings reported here suggest that nucleolar MageB2 might play a role in enhancing ribosome biogenesis as part of its repertoire to support cancer cell proliferation.

Trial watch: Peptide vaccines in cancer therapy

Prophylactic vaccination constitutes one of the most prominent medical achievements of history. This concept was first demonstrated by the pioneer work of Edward Jenner, dating back to the late 1790s, after which an array of preparations that confer life-long protective immunity against several infectious agents has been developed. The ensuing implementation of nation-wide vaccination programs has de facto abated the incidence of dreadful diseases including rabies, typhoid, cholera and many others. Among all, the most impressive result of vaccination campaigns is surely represented by the eradication of natural smallpox infection, which was definitively certified by the WHO in 1980. The idea of employing vaccines as anticancer interventions was first theorized in the 1890s by Paul Ehrlich and William Coley. However, it soon became clear that while vaccination could be efficiently employed as a preventive measure against infectious agents, anticancer vaccines would have to (1) operate as therapeutic, rather than preventive, interventions (at least in the vast majority of settings), and (2) circumvent the fact that tumor cells often fail to elicit immune responses. During the past 30 y, along with the recognition that the immune system is not irresponsive to tumors (as it was initially thought) and that malignant cells express tumor-associated antigens whereby they can be discriminated from normal cells, considerable efforts have been dedicated to the development of anticancer vaccines. Some of these approaches, encompassing cell-based, DNA-based and purified component-based preparations, have already been shown to exert conspicuous anticancer effects in cohorts of patients affected by both hematological and solid malignancies. In this Trial Watch, we will summarize the results of recent clinical trials that have evaluated/are evaluating purified peptides or full-length proteins as therapeutic interventions against cancer.

Targeted drug delivery using an aptamer against shared tumor-specific peptide antigen of MAGE-A3

We developed a DNA aptamer, Ap52, against the shared tumor-specific MAGE-A3_111-125 peptide antigen that was used to target multiple types of cancer cells. Here we report the in vivo study of mice implanted with pancreatic tumor cells AsPC-1, which demonstrates accumulation of phosphorothioate-modified Ap52 (ThioAp52) at the xenograft tumor following either intravenous or in situ injection. When complexed with antitumor drug doxorubicin (Dox), ThioAp52 achieves targeted delivery to four types of cancer cells, including breast, oral, pancreatic, and skin. Image analysis shows that ThioAp52-Dox complex selectively enters cancer cells, while free Dox is taken up by all cell lines. The cytotoxicity of ThioAp52-Dox for cancer cells is enhanced as compared to that for the corresponding normal/noncancerous cells. These results indicate that this aptamer against shared tumor-specific antigen can be a potential delivery vehicle for therapeutics to treat multiple cancers.

MAGE-A genes as predictors of the outcome of laryngeal squamous cell carcinoma

Laryngeal squamous cell carcinoma (LSCC) is one of the most common malignant tumors in the head and neck area. Melanoma-associated antigens A (MAGE-A) are strictly tumor-specific and are expressed in several types of tumors. To date, no studies have reported the potential of MAGE-A genes as markers for circulating tumor cells (CTCs) in patients with LSCC. The present study aimed to evaluate the expression and the possible prognostic significance of MAGE-A in the peripheral blood of patients with LSCC. In the present study, the expression of MAGE-A genes was determined by multiplex semi-nested PCR and restriction endonuclease treatment of the peripheral blood of patients with LSCC. The association between MAGE-A gene expression and clinicopathological parameters and prognosis was evaluated. The results demonstrated that the expression of MAGE-A was associated with the predictors that indicate poor prognosis. The expression levels of MAGE-A and each individual MAGE-A gene were also associated with a shorter overall survival time of patients with LSCC. In conclusion, the results of the present study suggested that the expression of MAGE-A genes may be a potential prognostic marker for patients with LSCC.

Molecular Signature of Subtypes of Non-Small-Cell Lung Cancer by Large-Scale Transcriptional Profiling: Identification of Key Modules and Genes by Weighted Gene Co-Expression Network Analysis (WGCNA)

Non-small-cell lung cancer (NSCLC) represents a heterogeneous group of malignancies consisting essentially of adenocarcinoma (ADC) and squamous cell carcinoma (SCC). Although the diagnosis and treatment of ADC and SCC have been greatly improved in recent decades, there is still an urgent need to identify accurate transcriptome profile associated with the histological subtypes of NSCLC. The present study aims to identify the key dysregulated pathways and genes involved in the development of lung ADC and SCC and to relate them with the clinical traits. The transcriptional changes between tumour and normal lung tissues were investigated by RNA-seq. Gene ontology (GO), canonical pathways analysis with the prediction of upstream regulators, and weighted gene co-expression network analysis (WGCNA) to identify co-expressed modules and hub genes were used to explore the biological functions of the identified dysregulated genes. It was indicated that specific gene signatures differed significantly between ADC and SCC related to the distinct pathways. Of identified modules, four and two modules were the most related to clinical features in ADC and SCC, respectively. CTLA4, MZB1, NIP7, and BUB1B in ADC, as well as GNG11 and CCNB2 in SCC, are novel top hub genes in modules associated with tumour size, SUVmax, and recurrence-free survival. Our research provides a more effective understanding of the importance of biological pathways and the relationships between major genes in NSCLC in the perspective of searching for new molecular targets.

Preclinical evaluation of an affinity-enhanced MAGE-A4-specific T-cell receptor for adoptive T-cell therapy

A substantial obstacle to the success of adoptive T cell-based cancer immunotherapy is the sub-optimal affinity of T-cell receptors (TCRs) for most tumor antigens. Genetically engineered TCRs that have enhanced affinity for specific tumor peptide-MHC complexes may overcome this barrier. However, this enhancement risks increasing weak TCR cross-reactivity to other antigens expressed by normal tissues, potentially leading to clinical toxicities. To reduce the risk of such adverse clinical outcomes, we have developed an extensive preclinical testing strategy, involving potency testing using 2D and 3D human cell cultures and primary tumor material, and safety testing using human primary cell and cell-line cross-reactivity screening and molecular analysis to predict peptides recognized by the affinity-enhanced TCR. Here, we describe this strategy using a developmental T-cell therapy, ADP-A2M4, which recognizes the HLA-A2-restricted MAGE-A4 peptide GVYDGREHTV. ADP-A2M4 demonstrated potent anti-tumor activity in the absence of major off-target cross-reactivity against a range of human primary cells and cell lines. Identification and characterization of peptides recognized by the affinity-enhanced TCR also revealed no cross-reactivity. These studies demonstrated that this TCR is highly potent and without major safety concerns, and as a result, this TCR is now being investigated in two clinical trials (NCT03132922, NCT04044768).

MAGE-A1 in lung adenocarcinoma as a promising target of chimeric antigen receptor T cells

BACKGROUND

Cancer/testis antigens (CTAs) are a special type of tumor antigen and are believed to act as potential targets for cancer immunotherapy.

METHODS

In this study, we first screened a rational CTA MAGE-A1 for lung adenocarcinoma (LUAD) and explored the detailed characteristics of MAGE-A1 in LUAD development through a series of phenotypic experiments. Then, we developed a novel MAGE-A1-CAR-T cell (mCART) using lentiviral vector based on our previous MAGE-A1-scFv. The anti-tumor effects of this mCART were finally investigated in vitro and in vivo.

RESULTS

The results showed striking malignant behaviors of MAGE-A1 in LUAD development, which further validated the rationality of MAGE-A1 as an appropriate target for LUAD treatment. Then, the innovative mCART was successfully constructed, and mCART displayed encouraging tumor-inhibitory efficacy in LUAD cells and xenografts.

CONCLUSIONS

Taken together, our data suggest that MAGE-A1 is a promising candidate marker for LUAD therapy and the MAGE-A1-specific CAR-T cell immunotherapy may be an effective strategy for the treatment of MAGE-A1-positive LUAD.

A cis-eQTL genetic variant in PLK4 confers high risk of hepatocellular carcinoma

Purpose

The overexpression and knockdown of PLK4 were both reported to generate aneuploidy. Thus, we aimed to investigate whether genetic variants in PLK4 contribute to the development of hepatocellular carcinoma (HCC).

Methods

We evaluated associations of common variants in PLK4 and its promoter for the risk of HCC in our association study (1300 cases and 1344 controls). The genotype‐tissue expression (GTEx) and The cancer genome atlas (TCGA) databases were used to quantify the expression of PLK4. Cell proliferation and migration affected by PLK4 in HCC were assessed in vitro. Drug susceptibility testing (DST) model was used to assess the sensibility of PLK4‐activated HCC to CFI‐400945, a small molecule inhibitor of PLK4.

Results

Herein, we found a significant association between rs3811741, located in the PLK4 intron, and liver cancer risk (OR = 1.26, P = 9.81 × 10⁻⁵). Although PLK4 expressed at lower levels in somatic tissues compared to the testis, the risk allele A of rs3811741 was associated with increased PLK4 expression in liver cancer tissues. Additionally, PLK4 high expression was remarkably associated with shortened survival of HCC (HR = 1.97, P = .001). Furthermore, overexpression of PLK4 promoted, while knockdown of PLK4 suppressed cancer cell proliferation, migration, and invasion. DST model demonstrated that CFI‐400945 can effectively suppress rampant proliferation of HCC with highly expressed PLK4.

Conclusion

Taken together, our study demonstrated that PLK4 is a susceptibility gene and plays an oncogenic role in HCC. Furthermore, we identified that PLK4 sensitives HCC to CFI‐400945, which may be an ideal therapy target for HCC.

Systematic cancer-testis gene expression analysis identified CDCA5 as a potential therapeutic target in esophageal squamous cell carcinoma

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is one of the most lethal malignancies with poor prognosis. Cancer-testis genes (CTGs) have been vigorously pursued as targets for cancer immunotherapy, but the expressive patterns and functional roles of CTGs remain unclear in ESCC.

METHODS

A systematic screening strategy was adopted to screen CTGs in ESCC by integrating multiple public databases and RNA expression microarray data from 119 ESCC subjects. For the newly identified ESCC prognosis-associated CTGs, an independent cohort of 118 patients with ESCC was recruited to validate the relationship via immunohistochemistry. Furthermore, functional assays were performed to determine the underlying mechanisms.

FINDINGS

21 genes were recognized as CTGs, in particular, CDCA5 was aberrantly upregulated in ESCC tissues and significantly associated with poor prognosis (HR = 1.85, 95%CI: 1.14-3.01, P = .013). Immunohistochemical staining confirmed that positive CDCA5 expression was associated with advanced TNM staging and a shorter overall survival rate (45.59% vs 28.00% for CDCA5-/+ subjects, P = 1.86 × 10-3). H3K27 acetylation in CDCA5 promoter might lead to the activation of CDCA5 during ESCC tumorigenesis. Functionally, in vitro assay of gain- and loss-of-function of CDCA5 suggested that CDCA5 could promote ESCC cells proliferation, invasion, migration, apoptosis resistance and reduce chemosensitivity to cisplatin. Moreover, in vivo assay showed that silenced CDCA5 could inhibit tumor growth. Mechanistically, CDCA5 knockdown led to an arrest in G2/M phase and changes in the expression of factors that played fundamental roles in the cell cycle pathway.

INTERPRETATION

CDCA5 contributed to ESCC progression and might serve as an attractive target for ESCC immunotherapy. FUND: This work was supported by the Natural Science Foundation of Jiangsu Province (No. BK20181083 and BK20181496), Jiangsu Top Expert Program in Six Professions (No. WSW-003 and WSW-007), Major Program of Science and Technology Foundation of Jiangsu Province (No. BE2016790 and BE2018746), Jiangsu Medical Young Talent Project (No. QNRC2016566), the Program of Jiangsu Medical Innovation Team (No. CXTDA2017006), Postgraduate Research & Practice Innovation Program of Jiangsu Province (KYCX18_1487) and Jiangsu Province 333 Talents Project (No. BRA2017545).

Functional and mechanistic studies reveal MAGEA3 as a pro-survival factor in pancreatic cancer cells

Background

In the era of personalized therapy, functional annotation of less frequent genetic aberrations will be instrumental in adapting effective therapeutic in clinic. Overexpression of Melanoma associated antigen A3 (MAGEA3) is reported in certain pancreatic cancer (PCA) patients. The major objective of the current study was to investigate the functional role of MAGEA3 in pancreatic cancer cells (PCCs) growth and survival.

Methods

Using overexpression (tet-on regulated system and constitutive expression system) and knockdown (by siRNA and shRNA) approach, we dissected the mechanistic role of MAGEA3 in pancreatic cancer pathogenesis. We generated MAGEA3 expressing stable PCA cell lines and mouse primary pancreatic epithelial cells. MAGEA3 was also depleted in certain MAGEA3 positive PCCs by siRNA or shRNA. The stable cells were subjected to in vitro assays like proliferation and survival assays under growth factor deprivation or in the presence of cytotoxic drugs. The MAGEA3 overexpressing or depleted stable PCCs were evaluated in vivo using xenograft model to check the role of MAGEA3 in tumor progression. We also dissected the mechanism behind the MAGEA3 role in tumor progression using western blot analysis and CCL2 neutralization.

Results

MAGEA3 overexpression in PCA cells did not alter the cell proliferation but protected the cells during growth factor deprivation and also in the presence of cytotoxic drugs. However, depletion of MAGEA3 in MAGEA3 positive cells resulted in reduced cell proliferation and increased apoptosis upon growth factor deprivation and also in response to cytotoxic drugs. The in vivo xenograft study revealed that overexpression of MAGEA3 promoted tumor growth however depleting the same hindered the tumor progression. Mechanistically, our in vitro and in vivo study revealed that MAGEA3 has tumor-promoting role by reducing macro-autophagy and overexpressing pro-survival molecules like CCL2 and survivin.

Conclusion

Our data proves tumor-promoting role of MAGEA3 and provides the rationale to target MAGEA3 and/or its functional mediators like CCL2 for PCA, which may have a better impact in PCA therapy.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1272-2) contains supplementary material, which is available to authorized users.

Expression of cancer-testis antigens in esophageal cancer and their progress in immunotherapy

PURPOSE

Esophageal cancer is a common disease in China with low survival rate due to no obvious early symptoms and lack of effective screening strategies. Traditional treatments usually do not produce desirable results in patients with advanced esophageal cancer, so immunotherapy which relies on tumor-related antigens is needed to combat low survival rates effectively. Cancer-testis antigens (CTA), a large family of tumor-related antigens, have a strong in vivo immunogenicity and tumor-restricted expressing patterns in normal adult tissues. These two characteristics are ideal features of anticancer immunotherapy targets and, therefore, promoted the development of some studies of CTA-based therapy. To provide ideas for the role of the cancer-testis antigens MAGE-A, NY-ESO-1, LAGE-1, and TTK in esophageal cancer, we summarized their expression, prognostic value, and development in immunotherapy.

METHODS

The relevant literature from PubMed is reviewed in this study.

RESULTS

In esophageal cancer, although the relationship between expression of MAGE-A, NY-ESO-1, LAGE-1, and TTK and prognosis value is still in a controversial situation, MAGE-A, NY-ESO-1, LAGE-1, and TTK are highly expressed and can induce specific CTL cells to produce particular killing effect on tumor cells, and some clinical trials have demonstrated that immunotherapy for esophageal cancer patients is effective and safe, which provides a new therapeutic strategy for the treatment of esophageal cancer in the future.

CONCLUSION

In this review, we summarize expression and prognostic value of MAGE-A, NY-ESO-1, LAGE-1, and TTK in esophageal cancer and point out recent advances in immunotherapy about them.

The Cancer/Testes (CT) Antigen HORMAD1 promotes Homologous Recombinational DNA Repair and Radioresistance in Lung adenocarcinoma cells

The Cancer/Testes (CT) Antigen HORMAD1 is germ cell-restricted and plays developmental roles in generation and processing of meiotic DNA Double Strand Breaks (DSB). Many tumors aberrantly overexpress HORMAD1 yet the potential impact of this CT antigen on cancer biology is unclear. We tested a potential role of HORMAD1 in genome maintenance in lung adenocarcinoma cells. We show that HORMAD1 re-distributes to nuclear foci and co-localizes with the DSB marker γH2AX in response to ionizing radiation (IR) and chemotherapeutic agents. The HORMA domain and C-term disordered oligomerization motif are necessary for localization of HORMAD1 to IR-induced foci (IRIF). HORMAD1-depleted cells are sensitive to IR and camptothecin. In reporter assays, Homologous Recombination (HR)-mediated repair of targeted ISce1-induced DSBs is attenuated in HORMAD1-depleted cells. In Non-Homologous End Joining (NHEJ) reporter assays, HORMAD1-depletion does not affect repair of ISce1-induced DSB. Early DSB signaling events (including ATM phosphorylation and formation of γH2AX, 53BP1 and NBS1 foci) are intact in HORMAD1-depleted cells. However, generation of RPA-ssDNA foci and redistribution of RAD51 to DSB are compromised in HORMAD1-depleted cells, suggesting that HORMAD1 promotes DSB resection. HORMAD1-mediated HR is a neomorphic activity that is independent of its meiotic partners (including HORMAD2 and CCDC36. Bioinformatic analysis of TCGA data show that similar to known HR pathway genes HORMAD1 is overexpressed in lung adenocarcinomas. Overexpression of HR genes is associated with specific mutational profiles (including copy number variation). Taken together, we identify HORMAD1-dependent DSB repair as a new mechanism of radioresistance and a probable determinant of mutability in lung adenocarcinoma.

Antitumor effect of recombinant Mycobacterium smegmatis expressing MAGEA3 and SSX2 fusion proteins

Mycobacterium smegmatis (M. smegmatis), which is a nonpathogenic and fast-growing mycobacterium, is a potential vaccine vector capable of expressing heterologous antigens. Spontaneous humoral and cellular immune responses have been demonstrated against cancer/testis antigens (CTA), including melanoma-associated antigen A (MAGEA) and SSX. In the present study, recombinant plasmids expressing MAGEA3 and SSX2 were constructed. The recombinant plasmids were transferred into M. smegmatis to generate the novel antitumor DNA vaccine. As MAGEA3 and SSX2 were in different ligation sequences, the two DNA vaccines were recombinant M. smegmatis MAGEA3-SSX2 (rM.S-MS) and recombinant M. smegmatis SSX2-MAGEA3 (rM.S-SM), respectively. The expression levels of Fusion proteins were assessed by western blotting. BALB/c mice were immunized with rM.S and western blot analysis was used to determine whether antibodies against MAGEA3 or SSX2 were produced in immunized mice. EC9706 cells were inoculated into BALB/c nude mice and the mice were maintained until an obvious visible tumor appeared on the back. Subsequently, the blood from the rM.S immunized BALB/c mice was injected into the BALB/c nude mice via the tail vein. In order to evaluate the antitumor effect of the vaccines, tumor volume and weight were measured 5 to 21 days after injection. Mice were euthanized on day 21 of tumor growth, and the tumor was dissected and weighed. The two fusion proteins were expressed in the rM.S and the specific fusion protein antibodies were expressed in the blood of immunized BALB/c mice. The tumor volumes and weight in the recombinant M. smegmatis MAGEA3 (rM.S-M) and recombinant M. smegmatis SSX2 (rM.S-S) groups were significantly reduced compared with the control group. Furthermore, the decrease in tumor volumes and weight in the rM.S-MS and rM.S-SM groups was more severe than in the rM.S-M or rM.S-S groups. There was no significant difference in the antitumor effect of the rM.S-MS and rM.S-SM groups. The present findings suggest that this rM.S may be a potential candidate therapeutic vaccine for the treatment of cancer.

Designer Oncolytic Adenovirus: Coming of Age

The licensing of talimogene laherparepvec (T-Vec) represented a landmark moment for oncolytic virotherapy, since it provided unequivocal evidence for the long-touted potential of genetically modified replicating viruses as anti-cancer agents. Whilst T-Vec is promising as a locally delivered virotherapy, especially in combination with immune-checkpoint inhibitors, the quest continues for a virus capable of specific tumour cell killing via systemic administration. One candidate is oncolytic adenovirus (Ad); it’s double stranded DNA genome is easily manipulated and a wide range of strategies and technologies have been employed to empower the vector with improved pharmacokinetics and tumour targeting ability. As well characterised clinical and experimental agents, we have detailed knowledge of adenoviruses’ mechanisms of pathogenicity, supported by detailed virological studies and in vivo interactions. In this review we highlight the strides made in the engineering of bespoke adenoviral vectors to specifically infect, replicate within, and destroy tumour cells. We discuss how mutations in genes regulating adenoviral replication after cell entry can be used to restrict replication to the tumour, and summarise how detailed knowledge of viral capsid interactions enable rational modification to eliminate native tropisms, and simultaneously promote active uptake by cancerous tissues. We argue that these designer-viruses, exploiting the viruses natural mechanisms and regulated at every level of replication, represent the ideal platforms for local overexpression of therapeutic transgenes such as immunomodulatory agents. Where T-Vec has paved the way, Ad-based vectors now follow. The era of designer oncolytic virotherapies looks decidedly as though it will soon become a reality.

Antibody response against cancer-testis antigens MAGEA4 and MAGEA10 in patients with melanoma

Melanoma-associated antigen A (MAGEA) represent a class of tumor antigens that are expressed in a variety of malignant tumors, however, their expression in healthy normal tissues is restricted to germ cells of testis, fetal ovary and placenta. The restricted expression and immunogenicity of these antigens make them ideal targets for immunotherapy in human cancer. In the present study the presence of naturally occurring antibodies against two MAGEA subfamily proteins, MAGEA4 and MAGEA10, was analyzed in patients with melanoma at different stages of disease. Results indicated that the anti-MAGEA4/MAGEA10 immune response in melanoma patients was heterogeneous, with only ~8% of patients having a strong response. Comparing the number of strongly responding patients between different stages of disease revealed that the highest number of strong responses was detected among stage II melanoma patients. These findings support the model that the immune system is involved in the control of melanoma in the early stages of disease.

hMAGEA2 promotes progression of breast cancer by regulating Akt and Erk1/2 pathways

Breast cancer is the most abundant cancer worldwide and a severe problem for women. Notably, breast cancer has a high mortality rate, mainly because of tumor progression and metastasis. Triple-negative breast cancer (TNBC) is highly progressive and lacks the expression of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). Therefore, there are no established therapeutic targets against TNBC. In this study, we investigated whether the expression of human melanoma-associated antigen A2 (MAGEA2) is associated with TNBC. We found that hMAGEA2 is significantly overexpressed in human TNBC tissues; we also observed oncogenic properties using TNBC cell lines (MDA-MB-231 and MDA-MB-468). The overexpression of hMAGEA2 in MDA-MB-231 cell line showed dramatically increased cellular proliferation, colony formation, invasion, and xenograft tumor formation and growth. Conversely, knockdown of hMAEGA2 in MDA-MB-468 cell line suppressed cellular proliferation, colony formation, and xenograft tumor formation. Additionally, we showed that hMAGEA2 regulated the activation of Akt and Erk1/2 signaling pathways. These data indicate that hMAGEA2 is important for progression of TNBC and may serve as a novel molecular therapeutic target.

An In vivo study: Adjuvant activity of poly-n-vinyl-2-pyrrolidone-co-acrylic acid on immune responses against Melanoma synthetic peptide

Peptides have been studied as an important class of components in medicine to control many major diseases with vaccination. Polymers as adjuvants are capable of enhancing the vaccine potential against various diseases by improving the delivery of antigens, and they reduce the booster doses of vaccines. In brief, polymers are promising candidates for peptide-based vaccine delivery platforms. The purpose of the present study was to create a possible alternative approach in the treatment of malignant melanoma and/or to prevent metastasis of melanoma. The study was designed as both an experimental and an in vivo study. We prepared a complex and covalent conjugate of MAGE-3 121-134 (L-L-K-Y-R-A-R-E-P-V-T-K-A-E) T-cell epitope as a vaccine candidate for melanoma. These conjugates were able to generate an immune response in mice after a single immunization, without the help of any external adjuvant. The peptide-polymer complexes activated the immune system in the best way and formed the highest antigen specific immune response. These results indicate the adjuvant activity of Poly(N-vinyl-2- pyrrolidone-co-acrylic acid) [P(VP-co-AA)] and the potential use of P(VP-coAA)-peptide based vaccine prototypes for future melanoma cancer vaccine formulations.

Strategies for Bispecific Single Chain Antibody in Cancer Immunotherapy

Genetic engineering has resulted in more than 50 recombinant bispecific antibody formats over the past two decades. Bispecific scFv antibodies represent a successful and promising immunotherapy platform that retargets cytotoxic T cells to tumor cells, with one scFv directed to tumor-associated antigens and the other to T cells. Based on this antibody construct, strategies for both specific tumor targeting and T cell activation are reviewed here. Three distinct types of tumor antigens are considered to optimize specificity and safety in bispecific scFv based treatment: cancer-testis antigens, neo-antigens and virus-associated antigens. In terms of T cell activation, although CD3 has been widely applied in bispecific scFvs being developed, CD28 and CD137 among co-stimulatory signals are also ideal candidates to be evaluated. Besides, LIGHT and HIV-Tat101 have drawn much attention as their potential roles in modulating antitumor responses.

T-Cell Receptor-Engineered Cells for the Treatment of Hematologic Malignancies

Recent attention in adoptive immunotherapy for hematologic malignancies has focused on lymphocytes expressing chimeric antigen receptors. An alternative technique to redirect the immune system toward cancer cells involves the use of T-cells carrying an engineered tumor-recognizing T-cell receptor (TCR). This approach allows targeting of surface or intracellular/nuclear proteins as long as they are processed and presented on the cell surface by human leukocyte antigen molecules. Several trials in advanced solid tumors, particularly melanoma and synovial sarcoma, support the validity of this strategy, although tumor responses have often been short-lived. Emerging data from patients with multiple myeloma and myeloid neoplasms suggest that the benefit of TCR-modified cells may extend to blood cancers. Methodological refinements may be necessary to increase the in vivo persistence and functionality of these cells. Particularly with affinity-enhanced TCRs, however, more effective therapies may increase the potential for serious toxicity due to the unexpected on- or off-target reactivity.

Critical roles of hMAGEA2 in induced pluripotent stem cell pluripotency, proliferation, and differentiation

Induced pluripotent stem (iPS) cells are important for clinical application and stem cell research. Although human melanoma-associated antigen A2 (hMAGEA2) expression is known to affect differentiation in embryonic stem cells, its specific role in iPS cells remains unclear. To evaluate the function of hMAGEA2 and its characteristics in iPS cells, we produced hMAGEA2-overexpressing iPS cells from hMAGEA2-overexpressing transgenic mice. Although the iPS cells with overexpressed hMAGEA2 did not differ in morphology, their pluripotency, and self-renewal related genes (Nanog, Oct3/4, Sox2, and Stat3), expression level was significantly upregulated. Moreover, hMAGEA2 contributed to the promotion of cell cycle progression, thereby accelerating cell proliferation. Through embryoid body formation in vitro and teratoma formation in vivo, we demonstrated that hMAGEA2 critically decreases the differentiation ability of iPS cells. These data indicate that hMAGEA2 intensifies the self-renewal, pluripotency, and degree of proliferation of iPS cells, while significantly repressing their differentiation efficiency. Therefore, our findings prove that hMAGEA2 plays key roles in iPS cells.

High expression of MAGE-A9 is associated with unfavorable survival in esophageal squamous cell carcinoma

Melanoma-associated antigens (MAGEs) are a group of well-characterized members of the cancer/testis antigen family, which are expressed in a variety of malignant tumors. MAGE-A9, a subfamily of MAGE-As, has been studied in a number of types of cancer and have been associated with unfavorable survival outcome. However, the expression of MAGE-A9 in human esophageal squamous cell carcinoma (ESCC) and association of MAGE-A9 with the clinicopathological characteristics of ESCC, particularly prognostic characteristics, remains unknown. The present study aimed at determining the expression level of MAGE-A9 and at evaluating its clinical significance in human ESCC. Quantitative polymerase chain reaction (qPCR) and immunohistochemistry (IHC) analyses were performed to characterize the expression of MAGE-A9 in ESCC tissues. Kaplan-Meier estimator survival and Coxs regression analyses were used to evaluate the prognosis of 103 patients with ESCC. The results of qPCR and IHC analysis revealed that the expression of MAGE-A9 was significantly increased in ESCC tissues, compared with that in healthy tissues. Furthermore, the expression level of MAGE-A9 protein in ESCC was significantly associated with the pathological grade (P=0.008), tumor size (P=0.027) and lymph node metastasis (P=0.009). Multivariate analysis using Coxs regression model identified that the expression level of MAGE-A9 and lymph node metastasis were independent prognostic factors for the overall survival rate of patients with ESCC (P=0.006 and P=0.001, respectively). The results of the present study are, to the best of our knowledge, the first to indicate that MAGE-A9 expression is a valuable prognostic biomarker for ESCC and that it may serve as a targeted therapy in the treatment of ESCC. Increased expression of MAGE-A9 indicated an unfavorable survival outcome in patients with ESCC.

Functional interaction between co-expressed MAGE-A proteins

MAGE-A (Melanoma Antigen Genes-A) are tumor-associated proteins with expression in a broad spectrum of human tumors and normal germ cells. MAGE-A gene expression and function are being increasingly investigated to better understand the mechanisms by which MAGE proteins collaborate in tumorigenesis and whether their detection could be useful for disease prognosis purposes. Alterations in epigenetic mechanisms involved in MAGE gene silencing cause their frequent co-expression in tumor cells. Here, we have analyzed the effect of MAGE-A gene co-expression and our results suggest that MageA6 can potentiate the androgen receptor (AR) co-activation function of MageA11. Database search confirmed that MageA11 and MageA6 are co-expressed in human prostate cancer samples. We demonstrate that MageA6 and MageA11 form a protein complex resulting in the stabilization of MageA11 and consequently the enhancement of AR activity. The mechanism involves association of the Mage A6-MHD domain to MageA11, prevention of MageA11 ubiquitinylation on lysines 240 and 245 and decreased proteasome-dependent degradation. We experimentally demonstrate here for the first time that two MAGE-A proteins can act together in a non-redundant way to potentiate a specific oncogenic function. Overall, our results highlight the complexity of the MAGE gene networking in regulating cancer cell behavior.

Suppression of MAGE-A10 alters the metastatic phenotype of tongue squamous cell carcinoma cells

MAGE-A10 is a member of the MAGE protein family (melanoma associated antigen) which is overexpressed in cancer cells. Although MAGE-A10 has been characterized for some time and is generally associated to metastasis its function remains unknown. Here we describe experiments using as models oral squamous cell carcinoma (OSCC) cell lines displaying increasing metastatic potential (LN1 and LN2). These cell lines were transduced with lentivirus particles coding for short hairpin against MAGE-A10 mRNA. Repression of MAGE-A10 expression in LN2 cells altered their morphology and impaired growth of LN1 and LN2 cell lines. Furthermore, repression of MAGE-A10 expression increased cell-cell and cell matrix adhesion. Furthermore shMAGEA10 cells were shown to assemble aberrantly on a 3D culture system (microspheroids) when compared to cells transduced with the control scrambled construct. Cell migration was inhibited in knocked down cells as revealed by two different migration assays, wound healing and a phagokinetic track motility assay. In vitro invasion assay using a leiomyoma tissue derived matrix (myogel) showed that shMAGEA10 LN1 and shMAGEA10 LN2 cells displayed a significantly diminished ability to penetrate the matrices. Concomitantly, the expression of E-cadherin, N-cadherin and vimentin genes was analyzed. shMAGEA10 activated the expression of E-cadherin and repression N-cadherin and vimentin transcription.

Taken together the results indicate that MAGE-A10 exerts its effects at the level of the epithelial-mesenchymal transition (EMT) presumably by regulating the expression of adhesion molecules.

A sensitive and disposable indium tin oxide based electrochemical immunosensor for label-free detection of MAGE-1

MAGE-1 (MAGE, for melanoma antigen), was identified by virtue of its processing and cell surface expression as a tumor-specific peptide bound to major histocompatibility complexes which was reactive with autolytic T cells. 3-Glycidoxypropyltrimethoxysilane (3-GOPS) is frequently employed for the preparation of dense heterometal hybrid polymers which are used, e.g., for hard coatings of organic polymers and contact lens materials in the optical industry. In this study, we have improved a new immunological biosensor with indium tin oxide (ITO). Then, Anti-MAGE-1 antibody was covalently immobilized with 3-GOPS which formed a self-assembled monolayers (SAMs) on modified ITO electrodes. Analytical characteristics such as square wave voltammetry, linear determination range, repeatability, reproducibility and regeneration of biosensors are determined. All characterization steps are monitored by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV). The developed biosensor has wide determination range (0.5fg-15fg/mL). To investigate long shelf life of the fabricated biosensor, the immunosensors were stored at 4°C for periods ten weeks. Futhermore, binding kinetics of MAGE1 to antiMAGE-1 is monitored by single frequency technique in real time. Additionally, Kramer's-Kronig transform was used to understand whether the impedance spectra of biosensor system are affected from the variation that occurred because of external factor. Morphological characteristics of constructed biosensor were observed by scanning electron microscopy. Real human serum samples were also analyzed by the proposed biosensor, successfully. A commercial ELISA kit was also used as a reference method to validate the results obtained by the biosensor. Finally, this biosensor was tried in real blood sample and that showed it could be utilized in clinical applications. This biosensor can be preferred due to it has a wide linear range and it can be prepared easily.

A Threshold of Systemic MAGE-A Gene Expression Predicting Survival in Resected Non-Small Cell Lung Cancer

Purpose: Quantitative measurement of minimal residual disease predicting recurrence in individual cancer patients is available only in very few indications, such as acute lymphoblastic leukemia, but is still missing in most solid tumors, including non-small cell lung cancer (NSCLC).Experimental Design: MAGE-A expression levels in blood and bone marrow determined as calibrator-normalized relative ratios by quantitative multimarker real-time RT-PCR for transcript amplification of MAGE-A1, -A2, -A3/6, -A4, -A10, and -A12 in 94 patients with completely resected NSCLC were correlated with survival in a clinical study.Results: Patients with MAGE-A expression levels ≥0.2 in at least one sample of bone marrow or blood at tumor surgery had a significantly reduced overall (P = 0.007), cancer-free (P = 0.002), and distant metastasis-free survival (P < 0.001) versus patients below 0.2 in all samples without significant difference in locoregional recurrence-free survival. The corresponding HRs (≥0.2 vs. <0.2) for death, cancer-related death, and development of distant metastasis were 2.56 [95% confidence interval (CI), 1.42-4.63], 3.32 (95% CI, 1.66-6.61), and 4.03 (95% CI, 1.77-9.18), respectively. Five-year Kaplan-Meier estimates of distant metastasis-free survival were 43% (MAGE-A ≥ 0.2) versus 87% (MAGE-A < 0.2).Conclusions: MAGE-A expression in blood or bone marrow at tumor surgery is an independent predictor of survival in resected NSCLC. The reliable prediction of distant metastasis in individual patients with a statistically proven impact on overall survival may help to refine patient selection for adjuvant therapy urgently needed, especially in the clinical management of elderly patients. Clin Cancer Res; 23(5); 1213-9. ©2016 AACR.

Biochemical and proteomic characterization of retrovirus Gag based microparticles carrying melanoma antigens

Extracellular vesicles are membraneous particles released by a variety of cells into the extracellular microenvironment. Retroviruses utilize the cellular vesiculation pathway for virus budding/assembly and the retrovirus Gag protein induces the spontaneous formation of microvesicles or virus-like particles (VLPs) when expressed in the mammalian cells. In this study, five different melanoma antigens, MAGEA4, MAGEA10, MART1, TRP1 and MCAM, were incorporated into the VLPs and their localization within the particles was determined. Our data show that the MAGEA4 and MAGEA10 proteins as well as MCAM are expressed on the surface of VLPs. The compartmentalization of exogenously expressed cancer antigens within the VLPs did not depend on the localization of the protein within the cell. Comparison of the protein content of VLPs by LC-MS/MS-based label-free quantitative proteomics showed that VLPs carrying different cancer antigens are very similar to each other, but differ to some extent from VLPs without recombinant antigen. We suggest that retrovirus Gag based virus-like particles carrying recombinant antigens have a potential to be used in cancer immunotherapy.

A neomorphic cancer cell-specific role of MAGE-A4 in trans-lesion synthesis

Trans-lesion synthesis (TLS) is an important DNA-damage tolerance mechanism that permits ongoing DNA synthesis in cells harbouring damaged genomes. The E3 ubiquitin ligase RAD18 activates TLS by promoting recruitment of Y-family DNA polymerases to sites of DNA-damage-induced replication fork stalling. Here we identify the cancer/testes antigen melanoma antigen-A4 (MAGE-A4) as a tumour cell-specific RAD18-binding partner and an activator of TLS. MAGE-A4 depletion from MAGE-A4-expressing cancer cells destabilizes RAD18. Conversely, ectopic expression of MAGE-A4 (in cell lines lacking endogenous MAGE-A4) promotes RAD18 stability. DNA-damage-induced mono-ubiquitination of the RAD18 substrate PCNA is attenuated by MAGE-A4 silencing. MAGE-A4-depleted cells fail to resume DNA synthesis normally following ultraviolet irradiation and accumulate γH2AX, thereby recapitulating major hallmarks of TLS deficiency. Taken together, these results demonstrate a mechanism by which reprogramming of ubiquitin signalling in cancer cells can influence DNA damage tolerance and probably contribute to an altered genomic landscape.

MAGE-A1-6 expression in patients with head and neck squamous cell carcinoma: impact on clinical patterns and oncologic outcomes

BACKGROUND

Various subtypes of melanoma-associated antigens (MAGEs) are expressed in the tumor tissues of patients with head and neck squamous cell carcinoma (HNSCC). However, little data are currently available on how the gene expression of MAGEs impacts clinical patterns and oncologic outcomes. We have therefore evaluated the expression of MAGE-A1-6 (A1-6) subtypes in tumor tissues of patients with HNSCC and the clinical impact of this expression.

METHODS

This was a retrospective review of 53 patients with histologically proven HNSCC of the oral cavity, oropharynx, larynx, or hypopharynx who underwent both treatment and analysis by reverse transcription (RT)-PCR assay with a common primer to identify the expression of MAGE-A1-6 subtypes in the tumor tissue. The clinicopathologic factors and oncologic outcomes of these patients and the correlations of both to MAGE-A1-6 gene expression were analyzed.

RESULTS

MAGE-A1-6 subtypes were expressed in the tumor tissues of 37 patients (69.8 %). Patient age of ≥65 years [p = 0.031, hazard ratio (HR) 4.866] and advanced American Joint Committee on Cancer stage (p = 0.035, HR 4.291) were independent risk factors for expression of MAGE-A1-6 subtypes. Patients with MAGE-A1-6 expression had lower disease-free survival (p = 0.029), disease-specific survival (p = 0.070), and overall survival (p = 0.017) rates. Overall survival rate was independently associated to chemotherapy (p = 0.011, HR 2.859), while no surgery (p = 0.050, HR 2.400) and MAGE-A1-6 expression (p = 0.050, HR 2.527) showed borderline significance.

CONCLUSION

In our patient group the expression of MAGE-A1-6 subtypes in tumor tissues of patients with HNSCC was correlated with advanced clinical stage of cancer and poor oncologic outcomes. We suggest that gene expression of MAGE-A1-6 subtypes may be considered to be a predictive factor to determine patient treatment or follow-up strategy.

Chemo/Photoacoustic Dual Therapy with mRNA-Triggered DOX Release and Photoinduced Shockwave Based on a DNA-Gold Nanoplatform

A multifunctional nanoparticle based on gold nanorod (GNR), utilizing mRNA triggered chemo-drug release and near-infrared photoacoustic effect, is developed for a combined chemo-photoacoustic therapy. The constructed nanoparticle (GNR-DNA/FA:DOX) comprises three functional components: (i) GNR as the drug delivery platform and photoacoustic effect enhancer; (ii) toehold-possessed DNA dressed on the GNR to load doxorubicin (DOX) to implement a tumor cell specific chemotherapy; and (iii) folate acid (FA) modified on GNR to guide the nanoparticle to target tumor cells. The results show that, upon an effective and specific delivery of the nanoparticles to the tumor cells with overexpressed folate receptors, the cytotoxic DOX loaded on the GNR-DNA nanoplatform can be released through DNA displacement reaction in melanoma-associated antigen gene mRNA expressed cells. With 808 nm pulse laser irradiation, the photoacoustic effect of the GNR leads to a direct physical damage to the cells. The combined treatment of the two modalities can effectively destroy tumor cells and eradicate the tumors with two distinctively different and supplementing mechanisms. With the nanoparticle, photoacoustic imaging is successfully performed in situ to monitor the drug distribution and tumor morphology for therapeutical guidance. With further in-depth investigation, the proposed nanoparticle may provide an effective and safe alternative cancer treatment modality.

Expression of MAGE-A1, -A9, -A11 in laryngeal squamous cell carcinoma and their prognostic significance: a retrospective clinical study

CONCLUSION

The melanoma-associated antigens A1, -A9, -A11 (MAGE-A1, -A9, -A11) are relatively tumor-specific in laryngeal squamous cell carcinoma (LSCC), and could be ideal antigens for LSCC immunotherapy. In addition, MAGE-A9 probably is a poor prognostic marker for LSCC patients.

OBJECTIVE

The MAGE-A family belongs to Cancer/testis antigens (CTA). However, the expression pattern of MAGE-A1, MAGE-A9, and MAGE-A11 in LSCC is still unclear. This study aims to evaluate the expression and possible prognostic role of MAGE-A1, MAGE-A9, and MAGE-A11 in LSCC patients.

METHODS

The expression of MAGE-A1, MAGE-A9, and MAGE-A11 in LSCC specimens was investigated by immunohistochemistry, and the association of their expression and the clinical parameters and the survival of LSCC patients were analyzed by chi-square test, Kaplan-Meier survival and Cox regression analysis.

RESULTS

The expression rates of MAGE-A1, MAGE-A9, and MAGE-A11 in LSCC were 54.7%, 46.2%, and 51.9%, respectively. The expression of MAGE-A1, MAGE-A9, and MAGE-A11 in LSCC was correlated with clinical stage, lymph node metastasis, and tumor size. The overall survival of LSCC patients with positive MAGE-A1, MAGE-A9, or MAGE-A11 expression was lower than the patients without MAGE-A1, MAGE-A9, or MAGE-A11 expression. Cox's multivariable analysis showed that MAGE-A9 expression was an independently poor prognostic factor for LSCC patients.

Novel Treatments in Development for Melanoma

The past several years can be considered a renaissance era in the treatment of metastatic melanoma. Following a 30-year stretch in which oncologists barely put a dent in a very grim overall survival (OS) rate for these patients, things have rapidly changed course with the recent approval of three new melanoma drugs by the FDA. Both oncogene-targeted therapy and immune checkpoint blockade approaches have shown remarkable efficacy in a subset of melanoma patients and have clearly been game-changers in terms of clinical impact. However, most patients still succumb to their disease, and thus, there remains an urgent need to improve upon current therapies. Fortunately, innovations in molecular medicine have led to many silent gains that have greatly increased our understanding of the nature of cancer biology as well as the complex interactions between tumors and the immune system. They have also allowed for the first time a detailed understanding of an individual patient's cancer at the genomic and proteomic level. This information is now starting to be employed at all stages of cancer treatment, including diagnosis, choice of drug therapy, treatment monitoring, and analysis of resistance mechanisms upon recurrence. This new era of personalized medicine will foreseeably lead to paradigm shifts in immunotherapeutic treatment approaches such as individualized cancer vaccines and adoptive transfer of genetically modified T cells. Advances in xenograft technology will also allow for the testing of drug combinations using in vivo models, a truly necessary development as the number of new drugs needing to be tested is predicted to skyrocket in the coming years. This chapter will provide an overview of recent technological developments in cancer research, and how they are expected to impact future diagnosis, monitoring, and development of novel treatments for metastatic melanoma.

Gene Network Rewiring to Study Melanoma Stage Progression and Elements Essential for Driving Melanoma

Metastatic melanoma patients have a poor prognosis, mainly attributable to the underlying heterogeneity in melanoma driver genes and altered gene expression profiles. These characteristics of melanoma also make the development of drugs and identification of novel drug targets for metastatic melanoma a daunting task. Systems biology offers an alternative approach to re-explore the genes or gene sets that display dysregulated behaviour without being differentially expressed. In this study, we have performed systems biology studies to enhance our knowledge about the conserved property of disease genes or gene sets among mutually exclusive datasets representing melanoma progression. We meta-analysed 642 microarray samples to generate melanoma reconstructed networks representing four different stages of melanoma progression to extract genes with altered molecular circuitry wiring as compared to a normal cellular state. Intriguingly, a majority of the melanoma network-rewired genes are not differentially expressed and the disease genes involved in melanoma progression consistently modulate its activity by rewiring network connections. We found that the shortlisted disease genes in the study show strong and abnormal network connectivity, which enhances with the disease progression. Moreover, the deviated network properties of the disease gene sets allow ranking/prioritization of different enriched, dysregulated and conserved pathway terms in metastatic melanoma, in agreement with previous findings. Our analysis also reveals presence of distinct network hubs in different stages of metastasizing tumor for the same set of pathways in the statistically conserved gene sets. The study results are also presented as a freely available database at http://bioinfo.icgeb.res.in/m3db/. The web-based database resource consists of results from the analysis presented here, integrated with cytoscape web and user-friendly tools for visualization, retrieval and further analysis.

An aptamer targeting shared tumor-specific peptide antigen of MAGE-A3 in multiple cancers

A DNA aptamer was identified against the shared tumor-specific MAGE-A3111-125 peptide antigen. The dissociation constant between the aptamer and the peptide was measured at 57 nM. Binding of the aptamer to seven types of cancer cells, melanoma, breast, colorectal, liver, lung, pancreas and oral cancer, was confirmed with flow cytometry and fluorescence imaging. Cy3-conjugated aptamers signals were specifically localized to the surface of those cancer cells. The results indicate that the DNA aptamer against the shared tumor-specific MAGE-A3 peptide can be used in cancer cell targeting and has the potential for developing into new modalities for the diagnosis of multiple cancers.

Induction of a specific CD8+ T-cell response to cancer/testis antigens by demethylating pre-treatment against osteosarcoma

Conventional non-surgical therapeutic regimens against osteosarcoma are subject to chemoresistance and tumor relapse, and immunotherapy may be promising for this tumor. However, it's hard to find satisfactory epitopes for immunotherapy against osteosarcoma. Cancer/testis antigens (CTAs), such as MAGE-A family and NY-ESO-1, the potential antigens that almost exclusively express in tumor cells and immune-privileged sites, have been found expressed in osteosarcoma also. Nevertheless, the expression of CTAs is downregulated in many tumors, constraining the application of immunotherapy. In this article, we demonstrate that the expression of MAGE-A family and NY-ESO-1 in osteosarcoma cells can be upregulated following treatment with demethylating agent 5-aza-2'-deoxycytidine and consequently induces a CTA specific CD8+ T-cell response against osteosarcoma in vitro and in vivo. The in vivo imaging was realized by using luciferase-transfected HOS cells and DiR labeled T-cells in severely combined immunodeficiency mouse models. Cytotoxic T cells specifically recognizing MAGE-A family and NY-ESO-1 clustered at the tumor site in mice pre-treated with DAC and resulted in tumor growth suppression, while it was not observed in mice without DAC pre-treatment. This study is important for more targeted therapeutic approaches and suggests that adoptive immunotherapy, combined with demethylating treatment, has the potential for non-surgical therapeutic strategy against osteosarcoma.

The expression of MAGE-C1 and MAGE-C2 in breast cancer and their clinical significance

BACKGROUND

Our study aims to analyze the expression pattern, mechanism, and prognostic significance of melanoma-associated antigen MAGE-C1 and MAGE-C2 in breast cancer.

METHODS

Reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry were used to investigate the expressions of MAGE-C1 and MAGE-C2 in breast benign disease specimens, tumor-free breast specimens, and breast cancer specimens; their correlation with clinicopathologic parameters and recurrence-free survival was elucidated. We examined the influence of DNA methylase inhibitor 5-aza-2'-deoxycytidine (5-aza-CdR) together with histone deacetylase inhibitor trichostatin A on the expression of MAGE-C1 and MAGE-C2 in breast cancer cell lines.

RESULT

Proteins for MAGE-C1 and MAGE-C2 expressions were 38.3% and 58.3% in breast cancer specimens, messenger RNA for MAGE-C1 and MAGE-C2 expressions were 43.3% and 61.7%, respectively. MAGE-C1 and MAGE-C2 expressions were positively associated with high tumor grade and reduced recurrence-free survival; MAGE-C2 expression was also associated with tumor embolus and histologic type. 5-aza-CdR treatment alone could induce expression of MAGE-C2, whereas trichostatin A was able to synergistically enhance 5-aza-CdR-mediated MAGE-C2 transcription.

CONCLUSIONS

MAGE-C1 and MAGE-C2 maybe potential targets for tumor immunotherapy, and their expressions are associated with advanced breast cancer and poor outcome.

Novel anti-melanoma treatment: focus on immunotherapy

Melanoma is an intractable cancer that is aggressive, lethal, and metastatic. The prognosis of advanced melanoma is very poor because it is insensitive to chemotherapy and radiotherapy. The incidence of melanoma has been ascending stably for years worldwide, accompanied by increasing mortality. New approaches to managing this deadly disease are much anticipated to enhance the cure rate and to extend clinical benefits to patients with metastatic melanoma. Due to its high degree of immunogenicity, melanoma could be a good target for immunotherapy, which has been developed for decades and has achieved certain progress. This article provides an overview of immunotherapy for melanoma.

MAGE-A Cancer/Testis Antigens Inhibit MDM2 Ubiquitylation Function and Promote Increased Levels of MDM4

Melanoma antigen A (MAGE-A) proteins comprise a structurally and biochemically similar sub-family of Cancer/Testis antigens that are expressed in many cancer types and are thought to contribute actively to malignancy. MAGE-A proteins are established regulators of certain cancer-associated transcription factors, including p53, and are activators of several RING finger-dependent ubiquitin E3 ligases. Here, we show that MAGE-A2 associates with MDM2, a ubiquitin E3 ligase that mediates ubiquitylation of more than 20 substrates including mainly p53, MDM2 itself, and MDM4, a potent p53 inhibitor and MDM2 partner that is structurally related to MDM2. We find that MAGE-A2 interacts with MDM2 via the N-terminal p53-binding pocket and the RING finger domain of MDM2 that is required for homo/hetero-dimerization and for E2 ligase interaction. Consistent with these data, we show that MAGE-A2 is a potent inhibitor of the E3 ubiquitin ligase activity of MDM2, yet it does not have any significant effect on p53 turnover mediated by MDM2. Strikingly, however, increased MAGE-A2 expression leads to reduced ubiquitylation and increased levels of MDM4. Similarly, silencing of endogenous MAGE-A expression diminishes MDM4 levels in a manner that can be rescued by the proteasomal inhibitor, bortezomid, and permits increased MDM2/MDM4 association. These data suggest that MAGE-A proteins can: (i) uncouple the ubiquitin ligase and degradation functions of MDM2; (ii) act as potent inhibitors of E3 ligase function; and (iii) regulate the turnover of MDM4. We also find an association between the presence of MAGE-A and increased MDM4 levels in primary breast cancer, suggesting that MAGE-A-dependent control of MDM4 levels has relevance to cancer clinically.

Restin suppressed epithelial-mesenchymal transition and tumor metastasis in breast cancer cells through upregulating mir-200a/b expression via association with p73

Background

Restin belongs to MAGE superfamily and is known as MAGE H1. Restin was firstly cloned from HL-60 cells treated with all-trans retinoic acid (ATRA). Previous studies showed a pro-apoptotic role of Restin in several cell lines. However, little information is available on its expression patterns and functions in vivo. Our study was performed to detect if Restin plays a role in breast cancer cells in vitro and in vivo.

Methods and results

Real-time PCR and western blot were conducted to detect Restin expression in multiple breast cancer cell lines and Restin level was negatively related with cell motility. Restin overexpression and knockdown stable cell lines were established by transducing lentivirus into MCF-7 and MDA-MB-231 cells. Cell morphology, wound closure assay, transwell migration and invasion assays were performed to detect if Restin inhibited EMT. Our data showed that Restin overexpressed cells exhibited classical epithelial cell morphology, and Restin overexpression resulted in activation of epithelial markers and suppression of mesenchymal markers, and inhibition of cell migration and invasion. Tumor xenograft model was used to characterize the biological functions of Restin in vivo. We found that Restin overexpression led to reduced lung metastasis. Real-time PCR, western blot, luciferase assay and ChIP assay were performed to identify the potential targets of Restin and the underlying molecular mechanisms. Among several master regulators of EMT, only ZEB1/2 levels were dramatically inhibited by Restin. Unexpectedly, Restin indirectly regulated ZEB1/2 expression at post-transcriptional level. We further identified mir-200a/b, well-characterized mediators controlling ZEB1/2 expression, were transcriptionally activated by Restin and the regulation was dependent on the p53 binding site in mir-200b/a/429 promoter. Further mechanical studies demonstrated Restin interacted with p73, one of p53 family members, which contributed to Restin-mediated activation of mir-200a/b and suppression of ZEB1/2.

Conclusions

Taken together, our results suggest that Restin inhibits EMT and tumor metastasis by controlling the expression of the tumor metastasis suppressor mir-200a/b via association with p73. Our findings not only establish a mechanistic link between Restin, EMT and tumor metastasis, but also provide strong evidence supporting the notion that MAGE Group II proteins may exert a tumor suppressive effect in vivo.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-015-0370-9) contains supplementary material, which is available to authorized users.

XAGE-1b cancer/testis antigen is a potential target for immunotherapy in prostate cancer

INTRODUCTION

Gene-modified cell vaccines are now considered to be the best way to achieve immunotherapy for a variety of cancers including prostate cancer (PCa). XAGE-1b is a member of the cancer/testis antigen family which has demonstrated strong immunogenicity. We investigated whether XAGE-1b is an ideal target for PCa immunotherapy.

MATERIALS AND METHODS

The recombinant eukaryotic expression vector pDisplay-XAGE-1b was constructed. Then the recombinant vector was transfected into Myc-CaP cells and its immunogenicity in vitro was studied. After transfection, the Myc-CaP-XAGE-1b cells were injected into FVB mice subcutaneously. Tumor growth was periodically observed and the anti-tumor effect and mechanism in vivo were further studied.

RESULTS

The recombinant vector was correctly constructed by DNA sequencing and restriction endonuclease digestion. Myc-CaP cells were successfully transfected with XAGE-1b gene by immunofluorescence staining and Western blot. The transfected cells exhibited increased IFN-γ secretion, decreased IL-6 secretion and enhanced killing activity. Tumor grew slower in XAGE-1b-modified FVB mice than in wild-type FVB mice. High dendritic cell expression and low myeloid-derived suppressor cell expression were observed in tumor tissues expressed with XAGE-1b.

CONCLUSIONS

XAGE-1b gene transfection could significantly enhance the immunogenicity of Myc-CaP cells. Therefore, XAGE-1b may be an attractive target for antigen-specific immunotherapy in PCa.

MAGED4 expression in glioma and upregulation in glioma cell lines with 5-aza-2'-deoxycytidine treatment

Melanoma-associated antigen (MAGE) family genes have been considered as potentially promising targets for anticancer immunotherapy. MAGED4 was originally identified as a glioma-specific antigen. Current knowledge about MAGED4 expression in glioma is only based on mRNA analysis and MAGED4 protein expression has not been elucidated. In the present study, we investigated this point and found that MAGED4 mRNA and protein were absent or very lowly expressed in various normal tissues and glioma cell line SHG44, but overexpressed in glioma cell lines A172,U251,U87-MG as well as glioma tissues, with significant heterogeneity. Furthermore, MAGED4 protein expression was positively correlated with the glioma type and grade. We also found that the expression of MAGED4 inversely correlated with the overall methylation status of the MAGED4 promoter CpG island. Furthermore, when SHG44 and A172 with higher methylation were treated with the DNA demethylating agent 5-aza-2'-deoxycytidine (5-AZA-CdR) reactivation of MAGED4 mRNA was mediated by significant demethylation in SHG44 instead of A172. However, 5-AZA-CdR treatment had no effect on MAGED4 protein in both SHG44 and A172 cells. In conclusion, MAGED4 is frequently and highly expressed in glioma and is partly regulated by DNA methylation. The results suggest that MAGED4 might be a promising target for glioma immunotherapy combined with 5-AZA-CdR to enhance its expression and eliminate intratumor heterogeneity.