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Duraiyan, D.

Publications and source records attributed to Duraiyan, D..

2 recordsLinked to original sources

Defining the RNA Modification Landscape of Multiple Myeloma Reveals METTL3-Dependent m6A Regulation of NEAT1

RNA modifications play critical roles in gene regulation. N6-methyladenosine (m6A) is the most abundant modification on mRNA and long noncoding RNA (lncRNA) and regulates RNA processing, stability, and translation. RNA modifications are not well characterized in multiple myeloma (MM), a plasma cell malignancy characterized by relapse and disease progression, and the contribution of m6A-modified lncRNAs to the disease remains unclear. Here, we define the RNA modification landscape of MM by combining mass spectrometry, Nanopore Direct RNA sequencing, and methylated RNA immunoprecipitation sequencing. We identify 20 RNA modification types and > 15,000 m6A sites, including sites on 2,398 lncRNAs. Among these, we validate m6A sites on the paraspeckle-associated lncRNA NEAT1. Functional studies reveal that NEAT1 expression is regulated by the methyltransferase METTL3 and site-specific demethylation of a NEAT1 m6A site reduces MM cell viability. Single-cell RNA sequencing shows consistent NEAT1 enrichment in malignant plasma cells but minimal expression in healthy cells. These findings identify m6A-modified lncRNAs as key regulators of MM biology and establish NEAT1 as an epitranscriptomically controlled driver of MM cell survival.

cancer biology↗

LINC01432 binds to CELF2 in newly diagnosed multiple myeloma promoting short progression-free survival to standard therapy

Multiple Myeloma (MM) is a highly prevalent and incurable form of cancer that arises from malignant plasma cells, with over 35,000 new cases diagnosed annually in the United States. While there are a growing number of approved therapies, MM remains incurable and nearly all patients will relapse and exhaust all available treatment options. Mechanisms for disease progression are unclear and in particular, little is known regarding the role of long non-coding RNAs (lncRNA) in mediating disease progression and response to treatment. In this study, we used transcriptome sequencing to compare newly diagnosed MM patients who had short progression- free survival (PFS) to standard first-line treatment (PFS < 24 months) to patients who had prolonged PFS (PFS > 24 months). We identified 157 differentially upregulated lncRNAs with short PFS and focused our efforts on characterizing the most upregulated lncRNA, LINC01432. We investigated LINC01432 overexpression and CRISPR/Cas9 knockdown in MM cell lines to show that LINC01432 overexpression significantly increases cell viability and reduces apoptosis, while knockdown significantly reduces viability and increases apoptosis, supporting the clinical relevance of this lncRNA. Next, we used individual-nucleotide resolution cross-linking immunoprecipitation with RT-qPCR to show that LINC01432 directly interacts with the RNA binding protein, CELF2. Lastly, we showed that LINC01432-targeted locked nucleic acid antisense oligonucleotides reduce viability and increases apoptosis. In summary, this fundamental study identified lncRNAs associated with short PFS to standard NDMM treatment and further characterized LINC01432, which inhibits apoptosis. Key points: lncRNA expression was found to be dysregulated in patients with short PFS to standard multiple myeloma therapy. LINC01432-bound CELF2 inhibits apoptosis.

cancer biology↗