Sedra Kremesh

Pharmacological inhibition of the nucleoside transporter hENT1 is a promising therapeutic target across a range of diseases, including cardiovascular disorders, neurodegenerative conditions, and cancer. However, current inhibitors lack drug-like properties, necessitating the development of new inhibitors with improved pharmacological profiles. We employed a dual-pharmacophore virtual screening protocol to identify putative hENT1 inhibitors from a library of over 2 million compounds, followed by structure-based molecular docking. To validate the inhibition effect of the lead compounds, we established a functional assay using gemcitabine (GEM)-induced cytotoxicity as a readout of hENT transport activity using eight cancer cell lines. H292 was the optimal cancer cell line for the validation assay based on its high GEM sensitivity (IC50 = 28 nM) and the concentration-dependent cytotoxicity inhibition of the reference inhibitor NBTI, a hENT1 inhibitor. Of the 19 candidate compounds, two leads (compounds 2 and 3) demonstrated potency comparable to NBTI, increasing GEM IC50 values by 2.2- and 2.9-fold at 5 µM, respectively. Both compounds were non-cytotoxic to normal fibroblasts, exhibited favorable ADME properties, displayed superior docking scores of −12.63 and −12.49 kcal/mol compared to NBTI (−9.06 kcal/mol), and displayed a novel vertical binding orientation within the hENT1 binding pocket distinct from NBTI’s horizontal mode. This study established a validated non-radioactive, gemcitabine-based functional assay for hENT inhibitor discovery and identified two putative inhibitors with therapeutic potential for cancer chemosensitization, pain management, and cardio- and neuroprotection. The non-radioactive functional assay overcomes the limitations of traditional radiolabeled methods, enabling scalable, broader screening applications.

Dysregulation of protein synthesis, folding, and secretion leads to endoplasmic reticulum (ER) stress, triggering the unfolded protein response (UPR). While the UPR is essential for cell survival under stress, its chronic activation in cancer cells supports tumorigenesis, metastasis, and chemoresistance by enabling cellular adaptation to hypoxia, nutrient deprivation, and oxidative stress. This review provides a comprehensive overview of the roles of key UPR mediators – binding immunoglobulin protein (BiP), protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK), inositol-requiring enzyme 1α (IRE1α), and activating transcription factor 6 (ATF6) – in cancer progression and therapy resistance. Furthermore, it discusses strategies to target UPR pathways, including small molecule inhibitors, gene therapies, natural compounds, and combination therapies, while it evaluates their preclinical and clinical relevance. Finally, it explores how modulating UPR signaling can overcome therapeutic resistance, improve immunotherapy outcomes, and reshape the tumor microenvironment. This review emphasizes the promise of UPR-targeted approaches in enhancing the efficacy of current cancer treatments and achieving better patient outcomes.

Cancer cells sustain rapid growth by reprogramming their metabolism to depend heavily on glycolysis, enhanced insulin signaling, and adaptive changes in the unfolded protein response (UPR). Insulin Potentiation Therapy (IPT) enhances the efficacy of chemotherapy by increasing insulin receptor expression, thereby improving the uptake of chemotherapeutic agents. Meanwhile, targeting endoplasmic reticulum (ER) stress disrupts the protein-folding machinery within cancer cells, steering them toward apoptosis. However, IPT faces several limitations, including limited clinical evidence, variable responses across tumor types, and concerns regarding safety and standardization. This review is the first to comprehensively examine the combined modulation of ER stress and IPT, highlighting novel clinical applications and presenting supporting evidence for this synergistic approach in cancer treatment. We compare the distinct metabolic features of cancer cells with those of normal cells and analyze how these differences contribute to tumor progression, the critical role of ER stress in cancer development, and the influence of insulin on cancer metabolism. In addition, we explore the potential synergy between IPT and ER stress modulation by delving into the mechanisms underlying IPT, the benefits of integrating ER stress modulation with IPT, and how insulin can modulate ER stress to improve therapeutic outcomes.

Cancer immunotherapy has emerged as a transformative approach in oncology, utilizing the body’s immune system to specifically target and destroy malignant cells. This review explores the scope and impact of various immunotherapeutic strategies, including monoclonal antibodies, chimeric antigen receptor (CAR)-T cell therapy, checkpoint inhibitors, cytokine therapy, and therapeutic vaccines. Monoclonal antibodies, such as Rituximab and Trastuzumab, have revolutionized treatment paradigms for lymphoma and breast cancer by offering targeted interventions that reduce off-target effects. CAR-T cell therapy presents a potentially curative option for refractory hematologic malignancies, although challenges remain in effectively treating solid tumors. Checkpoint inhibitors have redefined the management of cancers like melanoma and lung cancer; however, managing immune-related adverse events and ensuring durable responses are critical areas of focus. Cytokine therapy continues to play a vital role in modulating the immune response, with advancements in cytokine engineering improving specificity and reducing systemic toxicity. Therapeutic vaccines, particularly mRNA-based vaccines, represent a frontier in personalized cancer treatment, aiming to generate robust, long-lasting immune responses against tumor-specific antigens. Despite these advancements, the field faces significant challenges, including immune resistance, tumor heterogeneity, and the immunosuppressive tumor microenvironment. Future research should address these obstacles through emerging technologies, such as next-generation antibodies, Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR)-based gene editing, and AI-driven drug discovery. By integrating these novel approaches, cancer immunotherapy holds the promise of offering more durable, less toxic, and highly personalized treatment options, ultimately improving patient outcomes and survival rates.