Research Projects

Bortezomib, a first-in-class proteasome inhibitor, has revolutionized the treatment landscape for multiple myeloma (MM), markedly extending patient survival. Despite its success, the emergence of drug resistance—either intrinsic or acquired—remains a formidable clinical challenge. A significant proportion of patients eventually relapse or fail to respond to therapy, underscoring the urgent need to unravel the molecular basis of Bortezomib resistance and develop novel strategies to overcome it. Our preliminary investigations have established robust in vitro models of Bortezomib resistance using MM cell lines. Molecular profiling of these resistant clones reveals a complex resistance phenotype characterized by: 1. Upregulation of Wee1 kinase, a G2/M checkpoint regulator that phosphorylates and inhibits CDK1, allowing cancer cells to evade mitotic catastrophe and survive genotoxic stress. 2. Activation of oncogenic Ras and mTOR signaling pathways, which promote cell proliferation, protein synthesis, and survival under proteasome inhibition. 3. Dysregulated expression of long non-coding RNAs (lncRNAs), particularly MALAT1 and PURPL, which appear to modulate transcriptional and post-transcriptional programs associated with drug resistance. The central hypothesis driving this proposal is that the interplay between aberrant cell cycle control, oncogenic signaling, and lncRNA-mediated gene regulation underlies the adaptive response of MM cells to Bortezomib. Disrupting these interconnected networks may restore drug sensitivity and enhance therapeutic efficacy. To test this hypothesis, we will adopt a comprehensive, multidisciplinary strategy combining molecular, cellular, and systems-level approaches. Our proposed research is organized into four interrelated objectives: • Objective 1: Elucidate the role of cell cycle regulators, particularly Wee1 kinase, in mediating Bortezomib resistance. We will examine the expression and activity of Wee1 and its downstream targets in resistant cells and assess the impact of Wee1 inhibition (using pharmacological inhibitors or RNA interference) on cell cycle progression and apoptosis in the presence of Bortezomib. • Objective 2: Characterize the contribution of Ras and mTOR signaling to MM cell survival under proteasome stress. This will involve pathway activation assays, pharmacological inhibition studies, and proteomic profiling to uncover how these pathways are rewired in resistant states and whether their blockade re-sensitizes cells to Bortezomib. • Objective 3: Define the mechanistic roles of MALAT1 and PURPL in regulating transcriptional and post-transcriptional networks linked to drug resistance. We will perform lncRNA knockdown and overexpression experiments, RNA immunoprecipitation, and RNA-seq to map their targets and interaction partners, thereby unraveling their functional relevance in resistance. • Objective 4: Evaluate potential therapeutic strategies involving single and combination treatments targeting Wee1, Ras/mTOR, and lncRNAs. Using cell viability assays, apoptosis assays, and synergy analyses, we aim to identify effective co-targeting regimens that can overcome resistance. Promising strategies will be validated in MM xenograft models to assess in vivo efficacy. By systematically mapping the molecular circuitry that governs resistance, this research aims to identify novel biomarkers and therapeutic targets for precision medicine in MM. The anticipated outcomes include the development of combination therapies that co-target proteasome function and key resistance nodes, offering new hope for patients with refractory or relapsed disease.