N6-methyladenosine RNA modification (m6A) is of prognostic value in HPV-dependent vulvar squamous cell carcinoma.
Vulvar squamous cell carcinoma (VSCC) is an uncommon gynecologic malignancy but with an increasing incidence in recent years. Etiologically, VSCC is classified into two subtypes: HPV-dependent and HPV-independent. Localized VSCC is treated surgically and/or with radiation therapy, but for advanced, metastatic or recurrent disease, therapeutic options are still limited. N6-methyladenosine (m6A) is the most prevalent post-transcriptional messenger RNA (mRNA) modification and involved in many physiological processes. The group of m6A proteins can be further divided into: 'writers' (METTL3, METTL4, METTL14, WTAP, KIAA1429), 'erasers' (FTO, ALKBH5), and 'readers' (HNRNPA2B1, HNRNPC, YTHDC1, YTHDF1-3). Dysregulated m6A modification is implicated in carcinogenesis, progression, metastatic spread, and drug resistance across various cancer entities. Up to date, however, only little is known regarding the role of m6A in VSCC.
Here, we comprehensively investigated protein expression levels of a diverse set of m6A writers, readers and erasers by applying immunohistochemical staining in 126 patients with primary VSCC.
In the entire study cohort, dominated by HPV-independent tumors, m6A protein expression was not associated with clinical outcome. However, we identified enhanced protein expression levels of the 'writers' METTL3, METTL14 and the 'reader' YTHDC1 as poor prognostic markers in the 23 patients with HPV-dependent VSCC.
Our study suggests dysregulated m6A modification in HPV-associated VSCC.
Condic M
,Thiesler T
,Staerk C
,Klümper N
,Ellinger J
,Egger EK
,Kübler K
,Kristiansen G
,Mustea A
,Ralser DJ
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《BMC CANCER》
Comprehensive immunohistochemical analysis of N6-methyladenosine (m6A) writers, erasers, and readers in endometrial cancer.
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).
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.
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.
Overall, our study points toward dysregulated m6A modification in EC and its possibility to serve as a promising prognostic biomarker.
Ralser DJ
,Condic M
,Klümper N
,Ellinger J
,Staerk C
,Egger EK
,Kristiansen G
,Mustea A
,Thiesler T
... -
《-》
Research advances of N6-methyladenosine in diagnosis and therapy of pancreatic cancer.
N6-methyladenosine (m6A) is the addition of a methyl group on the N6 position of adenosine and is the most prevalent and abundant epigenetic modification in eukaryote mRNA. m6A marks are added to mRNA by the m6A methyltransferase complex ("writers"), removed by m6A demethylases ("erasers"), and recognized by m6A-binding proteins ("readers"). Recent evidence has shown that the m6A modification plays a crucial role in the pathogenic mechanism and malignant progression of pancreatic cancer, with roles in cell survival, proliferation, migration, invasion, tumor metastasis, and drug resistance.
Literature was searched in Pubmed and Web of Science for the following keywords: "N6-methyladenosine", "pancreatic cancer", "epigenetic modification", "immunotherapy".
Among classical m6A regulators, while METTL3, METTL14, WTAP, FTO, YTHDF2, IGF2BP1-3, hnRNPC, and NKAP are upregulated in pancreatic cancer, METTL16 and ALKBH5 are downregulated in pancreatic cancer. m6A modification has been investigated in pancreatic cancer therapy.
Dysregulated m6A and its related factors in pancreatic cancer cells and patients indicate their potential values as novel biomarkers in pancreatic cancer diagnosis and targeted therapy.
Chen S
,Ren H
,Zhang X
,Chang L
,Wang Z
,Wu H
,Zhang J
,Ren J
,Zhou L
... -
《-》
The potential role of RNA N6-methyladenosine in primary Sjögren's syndrome.
The pathogenesis of primary Sjögren's syndrome (pSS) remains incompletely understood. The N6-methyladenosine (m6A) RNA modification, the most abundant internal transcript modification, has close associations with multiple diseases. This study aimed to investigate the role of m6A in patients with pSS.
This study enrolled 44 patients with pSS, 50 age- and gender-matched healthy controls (HCs), and 11 age- and gender-matched patients with non-SS sicca. We detected the messenger RNA (mRNA) levels of m6A elements (including METTL3, WTAP, RBM15, ALKBH5, FTO, YTHDF1, YTHDF2, YTHDF3, YTHDC1, and YTHDC2), ISG15, and USP18 in peripheral blood mononuclear cells (PBMCs) from patients with pSS, patients with non-SS sicca, and HCs. The clinical characteristics and laboratory findings of patients with pSS and patients with non-SS sicca were also collected. We used binary logistic regression to determine if m6A elements were risk factors for pSS.
The mRNA levels of m6A writers (METTL3 and RBM15), erasers (ALKBH5 and FTO), and readers (YTHDF1, YTHDF2, YTHDF3, YTHDC1, and YTHDC2) were all significantly higher in PBMCs from patients with pSS than in HCs. The mRNA levels of m6A writers (METTL3 and WTAP) and readers (YTHDF2, YTHDF3, and YTHDC2) were lower in PBMCs from patients with pSS compared to patients with non-SS sicca. The expression of METTL3, RBM15, FTO, YTHDF1, YTHDF2, YTHDC1, and YTHDC2 was positively correlated with the level of C-reactive protein (CRP) of patients with pSS. The mRNA level of YTHDF1 in PBMCs from patients with pSS was negatively correlated with the EULAR Sjögren's syndrome disease activity index (ESSDAI) score. In patients with pSS, FTO, YTHDC1, and YTHDC2 were also related to white blood cells (WBCs), neutrophils, lymphocytes, and monocytes. Increased mRNA level of ALKBH5 in PBMCs was a risk factor for pSS, as determined by binary logistic regression analysis. The mRNA level of ISG15 was positively correlated with that of FTO, YTHDF2, YTHDF3, and YTHDC2 in patients with pSS.
Compared with HCs, the expression of METTL3, RBM15, ALKBH5, FTO, YTHDF1, YTHDF2, YTHDF3, YTHDC1, and YTHDC2 was considerably higher in PBMCs from patients with pSS. In comparison with patients with non-SS sicca, the expression of METTL3, WTAP, YTHDF2, YTHDF3, and YTHDC2 was reduced in PBMCs from patients with pSS. The m6A elements correlating with clinical variables may indicate the disease activity and inflammation status of pSS. Elevated expression of ALKBH5 was a risk factor for pSS. The dynamic process of m6A modification is active in pSS. m6A elements (FTO, YTHDF2, YTHDF3, or YTHDC2) might target ISG15, stimulate the expression of ISG15, and activate the type I IFN signaling pathway, playing an active role in initiating the autoimmunity in pSS.
Xiao Q
,Wu X
,Deng C
,Zhao L
,Peng L
,Zhou J
,Zhang W
,Zhao Y
,Fei Y
... -
《Frontiers in Medicine》