Study on the Gene Regulatory Effects in Leukemia Based on Multi-omics Mendelian Randomization, Network Pharmacology, and Functional Validation

Background: Leukemia is a type of malignant hematological disease, for which conventional treatments have limited efficacy, and there is an urgent need for novel therapeutic targets.This study investigates the causal effects of gene expression and plasma proteins on four subtypes of leukemia using a multi-omics integration strategy. Methods: Based on publicly available GWAS data from European populations, two-sample Mendelian randomization (MR) was employed to analyze the causal relationships between cis-expression quantitative trait loci (cis-eQTL, eQTLGen consortium, n=31,684) and cis-plasma protein quantitative trait loci (cis-pQTL, deCODE consortium, n=4,907) with four types of leukemia (FinnGen database, n≈345,000). Co-significant genes were screened through intersection analysis, and their associations were validated using the SMR method. At the experimental level, functional validation of key genes (CLEC1B/IGFLR1) was conducted in MEC-1/K562 leukemia cell lines: after siRNA silencing, silencing efficiency was detected by quantitative real-time PCR (qRT-PCR), proliferation and apoptosis were assessed using Cell Counting Kit-8 (CCK-8) and flow cytometry, and invasion ability was examined by Transwell assay. Targeted drugs were screened based on HEB and ITCM databases, and molecular docking simulations were performed using the CBDock2 platform. Results: MR analysis identified CLEC1B (chronic lymphocytic leukemia) and IGFLR1 (chronic myeloid leukemia) as significant causal genes (P<0.05). Cell experiments confirmed that silencing CLEC1B inhibited CLL cell proliferation and promoted apoptosis (P<0.05), and silencing IGFLR1 significantly inhibited CML cell proliferation, promoted apoptosis, and suppressed CML cell invasion (P<0.05). Molecular docking revealed that Coumestrol has strong binding potential with IGFLR1 (Vina score = -7.2). Conclusion: IGFLR1 and CLEC1B are potential targets for leukemia therapy, and their corresponding small molecule compounds provide new directions for drug development. This study integrates genetic and experimental evidence, laying the foundation for precision therapy in leukemia.