Development and validation of m6A regulators' prognostic significance for endometrial cancer

m6A mRNA methylation regulates the ERK/NF-κB/AKT signaling pathway through the PAPPA/IGFBP4 axis to promote proliferation and tumor formation in endometrial cancer

N6-methyladenosine (m6A) mRNA methylation has been considered a gene modulatory mechanism involved in disease progression and carcinogenesis. Herein, we aimed to explore the specific mechanism of m6A mRNA methylation in endometrial cancer. RT-qPCR was implemented to test the clinical correlation between m6A methylation and endometrial cancer. Bioinformatics analysis was performed to screen the genes related to endometrial cancer, and SRAMP was utilized for the prediction of m6A targets. Western blot assay and MeRIP-qPCR experiments were conducted to verify the effect of m6A methylation on the candidate genes and the signaling pathways involved in the occurrence of endometrial cancer. m6A-seq, RT-qPCR, and polysome profiling were used to confirm the mechanisms of m6A methylation in modulating related genes and pathways. The levels of m6A methylation, METTL3, and IGFBP4 were reduced in tumor tissues of patients with endometrial cancer, and SRAMP analysis confirmed that IGFBP4 and PAPPA had m6A methylation sites. Reduced m6A methylation promoted endometrial cancer cell progression and tumor formation in vivo. m6A methylation of RNA in endometrial cancer cells directly modulated IGFBP4 and PAPPA expression. m6A methylation regulated the PAPPA/IGFBP4 axis, thereby influencing endometrial cancer through the NF-κB and ERK signaling pathways. Knockdown of PAPPA or overexpression of IGFBP4 in endometrial cancer cells partially reduced disease progression caused by reduced m6A methylation. This research suggests that m6A mRNA methylation modulates the ERK/NF-κB/AKT signaling pathway through the PAPPA/IGFBP4 axis to induce cell proliferation and tumor formation in endometrial cancer. 1. METTL3 expressed modestly and m6A methylation of IGFBP4 and PAPPA mRNAs decreased in endometrial cancer; 2. YTHDF1-mediated IGFBP4 translation was reduced in HEC-1-A and AN3CA cells, and YTHDF2-mediated PAPPA mRNA degradation was blunted but its protein expression increased; 3. Increased PAPPA and reduced IGFBP4 activated IGF1-induced ERK, AKT, and NF-κB pathways by binding IGFR, thereby promoting cancer cell malignancy.

Identification and validation of ferroptosis-related lncRNA signature as a prognostic model for skin cutaneous melanoma

Background

Melanoma is a type of skin cancer, which originates from the malignant transformation of epidermal melanocytes, with extremely high lethality. Ferroptosis has been documented to be highly related to cancer pathogenesis and the effect of immunotherapy. In addition, the dysregulation of lncRNAs is greatly implicated in melanoma progression and ferroptosis regulation. However, the significance of ferroptosis-related lncRNA in melanoma treatment and the prognosis of melanoma patients remains elusive.

Methods

Via Least Absolute Shrinkage Selection Operator (LASSO) regression analysis in the TCGA SKCM database, a cutaneous melanoma risk model was established based on differentially-expressed ferroptosis-related lncRNAs (DEfrlncRNAs). The nomogram, receiver operating characteristic (ROC) curves, and calibration plots were conducted to examine the predictive performance of this model. Sequentially, we continued to analyze the differences between the high- and low-risk groups, in terms of clinical characteristics, immune cell infiltration, immune-related functions, and chemotherapy drug sensitivity. Moreover, the expressions of DEfrlncRNAs, PD-L1, and CD8 were also examined by qRT-PCR and immunohistochemical staining in melanoma tissues to further confirm the potential clinical implication of DEfrlncRNAs in melanoma immunotherapy.

Results

16 DEfrlncRNAs were identified, and a representative risk score for patient survival was constructed based on these 16 genes. The risk score was found to be an independent prognostic factor for the survival of melanoma patients. In addition, the low-risk group of patients had higher immune cell infiltration in the melanoma lesions, higher sensitivity to chemotherapeutic agents, and a better survival prognosis. Besides, the high expression of the identified 5 DEfrlncRNA in the low-risk group might suggest a higher possibility to benefit from immune checkpoint blockade therapy in the treatment of melanoma.

Conclusion

The DEfrlncRNA risk prediction model related to ferroptosis genes can independently predict the prognosis of patients with melanoma and provide a basis for evaluating the response of clinical treatment in melanoma.

Ferroptosis: Opportunities and Challenges in Treating Endometrial Cancer

Ferroptosis, a new way of cell death, is involved in many cancers. A growing number of studies have focused on the unique role of ferroptosis on endometrial cancer. In this study, we made a comprehensive review of the relevant articles published to get deep insights in the association of ferroptosis with endometrial cancer and to present a summary of the roles of different ferroptosis-associated genes. Accordingly, we made an evaluation of the relationships between the ferroptosis-associated genes and TNM stage, tumor grade, histological type, primary therapy outcome, invasion and recurrence of tumor, and accessing the different prognosis molecular typing based on ferroptosis-associated genes. In addition, we presented an introduction of the common drugs, which targeted ferroptosis in endometrial cancer. In so doing, we clarified the opportunities and challenges of ferroptosis activator application in treating endometrial cancer, with a view to provide a novel approach to the disease.

Comprehensive immunohistochemical analysis of N6-methyladenosine (m6A) writers, erasers, and readers in endometrial cancer

PURPOSE

N6-methyladenosine (m6A) is the most frequent type of messenger RNA (mRNA) modification and is implicated in diverse physiological processes. The procedure of m6A RNA modification is regulated by a dynamic interaction of writers (METTL3, METTL4, METTL14, WTAP, KIAA1429), erasers (FTO, ALKBH5), and readers (HNRNPA2B1, HNRNPC, YTHDC1, YTHDC1, YTHDF1-3). In the oncological context, alterations in m6A were identified to be critically involved in tumorigenesis, proliferation, angiogenesis, and drug resistance across diverse cancer entities including endometrial cancer (EC).

METHODS

In this study, we comprehensively examined the protein expression of m6A writers, readers and erasers by immunohistochemical staining in a cohort of N = 65 EC patients. Protein expression data were analyzed with regard to clinical outcomes.

RESULTS

We identified enhanced protein expression levels of METTL3, METTL14, FTO, HNRNPA2B1, and HNRNPC, respectively to be of prognostic value and linked to a shortened overall survival in EC.

CONCLUSION

Overall, our study points toward dysregulated m6A modification in EC and its possibility to serve as a promising prognostic biomarker.

The Potential Value of m6A RNA Methylation in the Development of Cancers Focus on Malignant Glioma

N6-methyladenosine (m6A) RNA methylation is an epigenetic modification that has emerged in the last few years and has received increasing attention as the most abundant internal RNA modification in eukaryotic cells. m6A modifications affect multiple aspects of RNA metabolism, and m6A methylation has been shown to play a critical role in the progression of multiple cancers through a variety of mechanisms. This review summarizes the mechanisms by which m6A RNA methylation induced peripheral cancer cell progression and its potential role in the infiltration of immune cell of the glioblastoma microenvironment and novel immunotherapy. Assessing the pattern of m6A modification in glioblastoma will contribute to improving our understanding of microenvironmental infiltration and novel immunotherapies, and help in developing immunotherapeutic strategies.

Emerging Roles of m6A RNA Methylation Regulators in Gynecological Cancer

Gynecological cancers seriously affect the reproductive system of females; diseases include ovarian tumors, uterine tumors, endometrial cancers, cervical cancers, and vulva and vaginal tumors. At present, the diagnosis methods of gynecological cancer are insufficiently sensitive and specific, leading to failure of early disease detection. N⁶-methyladenosine (m⁶A) plays various biological functions in RNA modification and is currently studied extensively. m⁶A modification controls the fate of transcripts and regulates RNA metabolism and biological processes through the interaction of m⁶A methyltransferase (“writer”) and demethylase (“erasers”) and the binding protein decoding m⁶A methylation (“readers”). In the field of epigenetics, m⁶A modification is a dynamic process of reversible regulation of target RNA through its regulatory factors. It plays an important role in many diseases, especially cancer. However, its role in gynecologic cancers has not been fully investigated. Thus, we review the regulatory mechanism, biological functions, and therapeutic prospects of m⁶A RNA methylation regulators in gynecological cancers.