Members of the MAGE-A family are expressed in a wide variety of tumor tissues, including hepatocellular carcinoma, non-small cell lung cancer, bladder cancer, vulvar cancer, colorectal tumors, and salivary gland tumors (Peng et al. 2005; Hou et al. 2020; Bergeron et al. 2009; Bellati et al. 2007; Park et al. 2002, 2012). Furthermore, recent studies have also confirmed the expression of MAGE-A4 in various malignancies such as breast cancer, esophageal squamous cell carcinoma, melanoma, and oral squamous cell carcinoma (Xiao et al. 2023; Sani et al. 2018; Freiberger et al. 2023; Montoro et al. 2012). This widespread distribution suggests that MAGE-A4 may have significant biological functions and clinical implications across multiple tumor types. The extensive presence of MAGE-A4 in diverse cancer types underscores its potential importance as a biomarker for cancer diagnosis and prognosis, as well as a potential therapeutic target. The consistent expression of MAGE-A4 across various malignancies also hints at a possible common mechanism in cancer development or progression, which warrants further investigation to elucidate its precise role in oncogenesis and tumor maintenance.

The role of MAGEA4 in lung cancer

The expression of MAGE-A4 (Melanoma-Associated Antigen A4) in lung cancer is associated with prognosis. MAGE-A4, a cancer/testis antigen, is overexpressed in various malignancies, including non-small cell lung cancer (NSCLC) (Hou et al. 2020). Studies have shown that MAGE-A4 is expressed in 4 out of 8 NSCLC cell lines, with an expression rate of 25.4% in clinical lung cancer specimens. Notably, the prognostic value of MAGE-A4 depends on its intracellular localization and p53 status. Patients with nuclear MAGE-A4 expression but lacking p53 expression had significantly lower survival rates compared to those expressing both nuclear MAGE-A4 and p53. In fact, multivariate analysis identified nuclear MAGE-A4 as an independent prognostic factor (P = 0.0042), albeit only in the absence of p53 (Fujiwara-Kuroda et al. 2018).

Further research has demonstrated that MAGE-A4 expression in peripheral blood of lung cancer patients correlates with clinical staging, tumor size, lymph node metastasis, and distant metastasis. MAGE-A4 expression is associated with lower overall survival in lung cancer patients (Gu et al. 2018). MAGEA4 protein expression is related to immune cell infiltration, with high MAGEA4 expression associated with M2-type macrophages (CD163) and regulatory T cells (FOXP3), while low MAGEA4 expression is associated with T cells (CD3), suggesting MAGEA4 may have immunogenic effects in the local tumor microenvironment (Hikmet et al. 2023).

In NSCLC, MAGE-A4 has been reported as a target for T cell-specific immunotherapy. Kathrin Davari, Tristan Holland, et al. employed a TCR-T approach, processing MAGE-A4 epitopes presented on HLA-A2 molecules encoded by the HLA-A*02:01 allele, enabling CD4 T cells to kill MAGE-A4 positive tumor cells (Davari, et al. 2021). Normal expression of HLA class-I in NSCLC is associated with good prognosis in MAGEA4-positive patients, while downregulation of HLA class-I may lead to disease progression, with smoking being one factor contributing to HLA class-I downregulation (Hanagiri et al. 2013).

Research indicates that high MAGE-A4 expression in lung adenocarcinoma patients is associated with response to immune checkpoint inhibitor (ICI) therapy. Leana Rich M Herrera, using “reverse vaccinology” and “immunoinformatics” approaches, computationally predicted a multi-epitope vaccine targeting MAGEA4 expression in NSCLC. The immunogenicity of the epitopes included in the vaccine was validated, and their antigenicity, non-allergenicity, non-toxicity, and physicochemical stability were assessed, highlighting the close relationship between MAGEA4 and immunotherapy (Herrera 2021). Additionally, studies have shown that Melanoma Antigen A4 is expressed in NSCLC and promotes cell apoptosis (Peikert et al. 2006).

In conclusion, MAGE-A4 likely plays a crucial role in the occurrence and development of lung cancer, making it an important target for lung cancer treatment.

The role of MAGEA4 in liver cancer

MAGE-A4, a tumor-associated antigen, exhibits an mRNA expression rate of up to 33.8% in hepatocellular carcinoma (HCC) tissues. Studies have revealed a positive correlation between MAGE-A4 expression levels and elevated serum AFP, advanced tumor stage, and high proliferation marker Ki-67, suggesting a close association with HCC's malignant phenotype and progression (Wang et al. 2015). Significant differences in MAGE-A4 positive expression rates are observed in peripheral blood mononuclear cells of HCC patients at different pathological stages, with rates reaching 40% in advanced patients compared to only 6.7% in early stages, indicating a positive correlation between MAGE-A4 expression levels and disease progression. Notably, MAGE-A4 is virtually unexpressed in healthy populations and chronic liver disease patients, suggesting its specificity in HCC (Hussein et al. 2012). These findings collectively suggest that MAGE-A4 expression could serve as a potential molecular marker for predicting HCC recurrence, metastasis, and prognosis assessment.

Functional studies have shown that the C-terminal fragment of MAGE-A4 protein (MAGE-A4N1) can induce tumor cell apoptosis. The molecular mechanism involves binding to the Miz-1 protein, inhibiting p21Cip1 transcription, thereby promoting the apoptotic process. The MAGE-A4N1 fusion protein can inhibit the anchorage-independent growth of HCC cells, demonstrating potential anti-cancer activity (Sakurai et al. 2004). Furthermore, MAGE-A4 can also bind to the Gankyrin protein, partially inhibiting Gankyrin overexpression-induced anchorage-independent growth and nude mouse tumor formation, revealing a new mechanism of MAGE-A4 in regulating tumor activity (Nagao et al. 2003).

Due to the highly restricted expression of MAGE-A4 in normal tissues, its abnormal expression in HCC provides an ideal target for tumor immunotherapy. Simultaneously, the detection of the MAGE-A4 gene in blood, especially in follow-up monitoring, may aid in assessing HCC prognosis and monitoring treatment response (Hussein et al. 2012). The interaction between MAGE-A4 and the chemotherapy drug doxorubicin also brings new insights into liver cancer treatment. Research has found that doxorubicin can promote MAGE-A4 cleavage by activating the proteasome, producing C-terminal fragments with pro-apoptotic activity, thereby enhancing the sensitivity of liver cancer cells to doxorubicin. This discovery not only helps understand the mechanism of doxorubicin but also provides the possibility of developing MAGE-A4’s C-terminal fragment as a novel anti-cancer drug (Sakurai et al. 2011).

In conclusion, the abnormal expression of MAGE-A4 in HCC and the unique functions of its encoded protein demonstrate potential clinical application value in disease diagnosis, prognosis assessment, and targeted therapy. In-depth research on the molecular regulatory network of MAGE-A4 and its role in HCC occurrence and development will lay the theoretical foundation for developing new diagnostic and therapeutic strategies. The multifaceted involvement of MAGE-A4 in HCC biology underscores its significance as a research focus in hepatocellular carcinoma.

The role of MAGEA4 in esophageal cancer

Esophageal cancer is a common and highly invasive malignant tumor of the digestive system, with esophageal squamous cell carcinoma (ESCC) being the predominant pathological type. Due to the lack of effective early screening and diagnostic methods, most ESCC patients are diagnosed at an advanced stage, resulting in poor prognosis (Mousavi et al. 2009). Therefore, there is an urgent need to discover new biomarkers for early diagnosis and personalized treatment of ESCC. MAGE-A4, a tumor-associated antigen, has been shown in multiple studies to be highly expressed in ESCC tissues (Sani et al. 2018; Tang et al. 2016). Real-time RT-PCR and immunohistochemical analyses have demonstrated significant mRNA and protein expression of MAGE-A4 in 60% to 90% of ESCC samples (Cuffel et al. 2011; Bujas et al. 2011). Notably, MAGE-A4 expression exhibits heterogeneity within tumors, with some regions showing higher expression intensity.

Importantly, MAGE-A4 expression levels are significantly correlated with tumor invasion depth, clinical stage, and lymph node metastasis status, suggesting its potential involvement in ESCC progression and metastasis (Sani et al. 2018). Multiple cohort studies have found that high MAGE-A4 expression levels in ESCC tissues are significantly associated with poor patient prognosis. MAGE-A4-positive patients have markedly shorter overall survival compared to negative patients. Even in early-stage ESCC patients, high MAGE-A4 expression is an independent indicator of poor prognosis (Tang et al. 2016). These results suggest that MAGE-A4 can serve as a molecular marker for predicting ESCC patient prognosis.

Functional studies further indicate that MAGE-A4 may play a carcinogenic driving role in the occurrence and development of ESCC through various molecular mechanisms. At the molecular level, MAGEA4 may play a role in tumor progression by modulating the NF-κB and MMP2 signaling pathways (Liu et al. 2014). On the other hand, the TWIST1 transcription factor can bind to the MAGE-A4 promoter region and upregulate its expression (Forghanifard et al. 2017). Therefore, MAGE-A4 is considered a potential oncogene in ESCC.

Immunologically, MAGE-A4 can induce autoantibodies and T cell immune responses in esophageal cancer patients. Some non-vaccinated esophageal cancer patients naturally acquire humoral immune responses to MAGE-A4 and MAGE-A4-specific CD4 + and CD8 + T cell responses. This lays the foundation for developing active immunotherapy targeting MAGE-A4 (Saito et al. 2014). Multiple clinical trials have evaluated the safety and immunogenicity of MAGE-A4 protein vaccines in patients with solid tumors, including esophageal cancer. Results show that MAGE-A4 protein vaccines have good safety profiles and can induce or enhance MAGE-A4-specific antibody responses in patients (Saito et al. 2014). In a phase II clinical trial, 24% of patients vaccinated with MAGE-A4 developed MAGE-A4-specific immune responses (Ueda et al. 2018). (As shown in Fig. 3A and B).

Fig. 3

MAGEA4 in Tumor Immunotherapy. A Antigen Presentation of MAGEA4 Peptide Vaccines (Targeting the cancer mutanome 2017), B Mechanisms of Action of MAGEA4 Peptide Vaccines (Alsalloum et al. 2023), C TCR-T Therapy Targeting MAGEA4 (Restifo et al. 2012)

Another immunotherapy strategy is MAGE-A4-specific TCR-transduced T cell therapy (As shown in Fig. 3C). Researchers collect peripheral blood lymphocytes from patients, transduce these cells with T cell receptor (TCR) genes that recognize MAGE-A4, enabling them to acquire specific killing ability against MAGE-A4. After in vitro expansion, these TCR-engineered T cells are reinfused into patients (Tanaka et al. 2017). A phase I clinical trial for recurrent esophageal cancer patients showed that MAGE-A4-specific TCR-transduced T cells could survive long-term in patients and maintain reactivity against tumors, potentially benefiting patients with lower tumor burden. Although no significant tumor shrinkage was observed in the short term, this strategy demonstrated potential clinical value (Kageyama et al. 2015).

Studies have found that patients with high co-expression of MAGE-A4 and MHC class I molecules in tumor cells are more likely to develop MAGE-A4-specific immune responses after MAGE-A4 vaccination and have longer overall survival. Therefore, co-expression of MAGE-A4 and MHC molecules in tumor cells may be an important prognostic marker for the efficacy of MAGE-A4 immunotherapy (Saito et al. 2014). NY-ESO-1 is another tumor-associated antigen co-expressed with MAGE-A4 in some esophageal cancers. Research has shown that patients co-expressing these two antigens have poorer prognosis, but may experience antigen spread to NY-ESO-1 after MAGE-A4 vaccination, potentially leading to better treatment outcomes (Bujas et al. 2011; Ueda et al. 2018; Chen et al. 2017). Thus, NY-ESO-1 expression status is also an important factor in evaluating the potential of MAGE-A4 immunotherapy.

In addition to the above factors, immunosuppressive elements in the local tumor microenvironment, such as regulatory T cells, may also affect the efficacy of MAGE-A4 immunotherapy (Kawada et al. 2012). Overall, MAGE-A4, as a tumor-associated antigen, demonstrates good immunogenicity in esophageal cancer patients. Various immunotherapy strategies based on MAGE-A4 are under clinical investigation and show some clinical benefits (Table 3). However, the factors affecting immunotherapy efficacy are complex, requiring further research to optimize treatment strategies for greater benefits to esophageal cancer patients.

Table 3 Clinical Trial for MAGE-A4 Positive Patients (Data source: ClinicalTrials.gov, URL: https://clinicaltrials.gov/search?term=magea4&viewType=Table)

At the basic research level, researchers have identified the HLA-A2-restricted epitope p286-1Y2L9L derived from MAGE-A4, which can induce specific cytotoxic T lymphocytes (CTLs) capable of killing MAGE-A4-positive tumor cells. In HLA-A2.1/Kb transgenic mouse models, CTLs induced by the p286-1Y2L9L peptide can recognize and kill MAGE-A4-positive tumor cells (Wu et al. 2011). In NOG mice (SCID/γcnull mice), MAGE-A4-specific TCR-transduced human PBMCs can infiltrate tumor tissues and inhibit tumor growth (Shirakura et al. 2012). These basic studies have laid the foundation for the clinical translation of MAGE-A4 immunotherapy.

The role of MAGEA4 in head and neck cancers

MAGE-A4 is a tumor-associated antigen that exhibits elevated expression levels in various head and neck tumors. Studies have revealed that MAGE-A4 is expressed in approximately 50% of cases of nasopharyngeal carcinoma, oral squamous cell carcinoma, and laryngeal cancer, with expression rates reaching up to 90% in certain cancer types (Figueiredo et al. 2006; Brisam et al. 2016). Notably, MAGE-A4 expression within tumor tissues is heterogeneous, with some regions displaying higher expression levels. In contrast, it is virtually absent in normal tissues, with only minimal expression in specialized tissues such as the testes, thus conferring high tumor specificity (Figueiredo et al. 2011).Multiple studies have demonstrated that high MAGE-A4 expression levels correlate with advanced clinical stages, increased metastatic potential (e.g., lymph node metastasis), and poorer prognosis, including shortened overall survival. MAGE-A4 expression is more prevalent in advanced, high-grade head and neck tumors (Brisam et al. 2016). Research has directly confirmed MAGE-A4 as an independent prognostic factor for adverse outcomes (Laban et al. 2019).

At the molecular level, MAGE-A4 may promote tumor cell proliferation by suppressing the expression of apoptosis-related genes (such as p53 downstream genes BAX and CDKN1A). Its expression is also associated with DNA methylation levels, and demethylating agents can induce upregulation of MAGE-A4 expression (Bhan et al. 2012).

Due to its high specificity and overexpression in tumor tissues, MAGE-A4 is considered a potential tumor-associated antigen and a target for cancer immunotherapy. Studies have isolated MAGE-A4-reactive CD4 + T cells from unvaccinated head and neck cancer patients and identified novel helper epitopes of MAGE-A4, laying the foundation for vaccine development. Combining MAGE-A4 with other MAGE family members (e.g., MAGE-A3) or other tumor-associated antigens may lead to more effective multi-target immunotherapy strategies (Cesson et al. 2011).Furthermore, detection of MAGE-A4 expression may aid in the early detection and diagnosis of head and neck tumors. In some cases, its expression may reveal potential risks of malignant transformation, guiding timely treatment and improving diagnostic accuracy as a molecular biomarker. Research has shown that MAGE-A4 expression positively correlates with the expression of other cancer-testis antigens such as LAGE1 and NY-ESO1, suggesting these antigens may play synergistic roles in tumor development and progression (Forghanifard et al. 2011).

The expression pattern of MAGE-A4 in head and neck tumors may also be associated with clinical factors such as patients' smoking habits (Figueiredo et al. 2006). Additionally, MAGE-A4 expression varies across different tumor regions, often exhibiting lower expression in invasive front areas (Brisam et al. 2016).

In conclusion, MAGE-A4 demonstrates significant biological and clinical value in head and neck tumors. It not only serves as a prognostic marker but, more importantly, holds potential applications in cancer immunotherapy and early diagnosis. These aspects warrant further in-depth research and development for clinical utilization.

The role of MAGEA4 in breast cancer

The aberrant expression of cancer/testis antigen (CTA) MAGE-A4 in triple-negative breast cancer (TNBC) and certain other breast cancer subtypes, along with its clinical significance, has garnered considerable attention. Studies have revealed MAGE-A4 expression in 29.41% of TNBC samples, with its positive expression associated with prolonged disease-free survival, suggesting its potential as an immunotherapeutic target for TNBC. At least one of MAGE-A4, NY-ESO-1, or PRAME is expressed in 76.47% of TNBC cases. MAGE-A4 expression correlates with WHO tumor grade, indicating lower tumor differentiation, but shows no significant association with other clinical factors such as age, lymph node status, tumor size, lymphovascular invasion, or perineural invasion (Xiao et al. 2023).

Artificial intelligence models have identified that high MAGE-A4 expression in breast cancer is associated with reduced chemotherapy sensitivity. Its downregulation can inhibit cell migration and wound healing, potentially relating to tumor metastatic potential. Mechanistic studies indicate that MAGE-A4 may contribute to chemotherapy resistance acquisition through the CDKN2A/STAT3 pathway, and is associated with the expression of PD-L1 and the apoptosis-related protein caspase-3, influencing tumor cell survival and apoptosis processes (Wan et al. 2023).

Multiple preclinical studies have evaluated immunotherapeutic strategies targeting MAGE-A4. Multi-antigen targeted T cells capable of recognizing MAGE-A4 and eliciting immune responses have shown some disease control in a subset of patients (Hoyos et al. 2022). Another approach involves developing high-affinity, co-receptor-independent MAGE-A4-specific TCR-T cell products. Preclinical evaluations demonstrate their ability to activate various T cell subsets, potentially offering enhanced cellular responses in clinical settings (Davari, et al. 2021).Furthermore, cancer vaccines targeting MAGE-A4 or MAGE-A family members, such as the H/K-HELP vaccine, have shown promising efficacy in some patients by stimulating Th1 and Tc1 cell cancer-specific immune responses and inducing IgG1 and IgG3 antibody production. Notably, one TNBC patient achieved complete remission (Nishimura 2012).

MAGE-A4 is also highly expressed in BRCA1/2-associated breast cancers, with 13 out of 26 cases (50%) testing positive. Given its absence in normal breast tissue, MAGE-A4 emerges as a potential target for developing preventive vaccines for BRCA mutation carriers (Adams et al. 2011).

Immune-enriched TNBC presents a distinct immune microenvironment and therapeutic targets compared to ER-positive breast cancer, with overexpression of immune-related genes such as IFNG, PD-L1, and CTLA4 in TNBC, necessitating different immunotherapeutic strategies (O'Meara, et al. 2020).

MAGE-A4 expression is significant in TNBC and HER2-positive/ER-negative breast cancers, detectable in tumor interstitial fluid and serum. Its positive expression correlates with high-grade tumor classification and may serve as a prognostic indicator for breast cancer (Cabezon et al. 2013; Hussein et al. 2011).

As a member of the MAGE-A family, MAGE-A4 may regulate germ cell proliferation, differentiation, and survival, with similar functions in cancer cells, involving processes of cell proliferation, stem cell function, and tumor development (Cabezon et al. 2013).

In conclusion, MAGE-A4 represents a potential therapeutic target and prognostic marker for TNBC and certain other breast cancer subtypes, holding significant clinical relevance and research value in the field of tumor immunotherapy.

The role of MAGEA4 in other cancers

MAGE-A4 is a cancer/testis antigen (CTA) with strictly limited expression in normal tissues but widespread and high expression in various solid tumors and hematological malignancies, playing a significant role in cancer biology. In tenosynovial giant cell tumors, the average rate of MAGE-A4-positive cells reaches 68.9%, showing a significant negative correlation with β-catenin expression (r = −0.64). This suggests that MAGE-A4 may interact with β-catenin, potentially contributing to tumor development (Hashimoto, et al. 2023).

In malignant soft tissue sarcomas, MAGE-A4 positivity strongly correlates with tumor metabolic activity as measured by SUVmax, reflecting its possible influence on tumor biological behavior through regulation of related pathways (Hashimoto et al. 2022). As a CTA, MAGE-A4 plays a role in the immune response to sarcomas, although not all patients respond to it, possibly due to MAGE-A4-mediated tumor immune evasion mechanisms.

A phase I clinical trial using the MAGE-A4-specific TCR-T cell product afamitresgene autoleucel for solid tumor treatment achieved a 44% response rate in synovial sarcoma patients, demonstrating MAGE-A4’s potential in cancer immunotherapy (Hong et al. 2023). In head and neck mucosal melanoma, MAGE-A4 expression reaches 61%, suggesting the potential applicability of MAGE-A4-based immunotherapy strategies, such as MAGE-A4-specific TCR-T cell therapy (Prasad et al. 2004).

MAGE-A4 is closely associated with normal germ cell development. It is expressed in germ cell neoplasia in situ (GCNIS) cells, precursors of testicular germ cell tumors. Through interactions with molecules like Gankyrin and mediation of signaling pathways such as p53, MAGE-A4 may exert anti-proliferative effects and participate in the invasive transformation of GCNIS (Camacho-Moll et al. 2019).

In pancreatic cancer, MAGE-A4 expression is relatively low but may be regulated by epigenetic mechanisms such as DNA methylation and histone deacetylase inhibitors. Due to its absence in