HSP90 inhibition acts synergistically with heat to induce a pro-immunogenic form of cell death in colon cancer cells

AUY922 improves sensitivity to sunitinib in clear cell renal cell carcinoma based on network pharmacology and in vitro experiments

Clear Cell Renal Cell Carcinoma (ccRCC), the most prevalent form of renal cell carcinoma (RCC), poses a significant threat to human health due to its rising morbidity and mortality rates. Sunitinib, a pivotal targeted drug for the treatment of ccRCC, presents a significant challenge due to the high susceptibility of ccRCC to resistance. HSP90 inhibitor AUY922 has demonstrated anti-tumor activity in a range of cancer types. However, its efficacy in combination with sunitinib for ccRCC treatment has not been evaluated. In this study, we employed bioinformatics, network pharmacology, and in vitro assays to verify that AUY922 inhibits cell viability, proliferation, and migration of ccRCC cell lines 786-O and ACHN, with IC50s of 91.86 μM for 786-O and 115.5 μM for ACHN. The effect of AUY922 enhancing the inhibitory effect of sunitinib on ccRCC was further confirmed. The CCK-8 assay demonstrated that the IC50 of sunitinib was reduced from 15.10 μM to 11.91 μM for 786-O and from 17.65 μM to 13.66 μM for ACHN, after the combined application of AUY922. The EdU assay and wound healing assay indicated that AUY922 augmented the inhibitory impact of sunitinib on the proliferation and migration of ccRCC cells. Western blot and RT-PCR analyses demonstrated that AUY922 increased the sensitivity of ccRCC cells to sunitinib by targeting the HIF-1α/VEGFA/VEGFR pathway. Our study represents the first investigation into the role and mechanism of AUY922 in enhancing the sensitivity of ccRCC to sunitinib. In conclusion, the findings indicate the potential for AUY922 to enhance the therapeutic efficacy of sunitinib and overcome sunitinib resistance in ccRCC.

Enhancing Magnetic Hyperthermia Efficacy through Targeted Heat Shock Protein 90 Inhibition: Unveiling Immune-Mediated Therapeutic Synergy in Glioma Treatment

The induction of heat stress response (HSR) mediated by the generation of heat shock proteins (HSPs) on exposure to magnetic hyperthermia-mediated cancer therapy (MHCT) decreases the efficacy of localized heat treatment at the tumor site, and thus therapy remains a significant challenge. Hence, the present study examined differential HSR elicited in glioma cells post-MHCT under different tumor microenvironment conditions (2D monolayers, 3D monoculture, and coculture spheroids) to recognize target genes that, when downregulated, could enhance the therapeutic effect of MHCT. Gene expression analysis following MHCT revealed that HSP90 was upregulated as compared to HSP70. Hence, to enhance the efficacy of the treatment, a combinatorial strategy using 17-DMAG as an inhibitor of HSP90 following MHCT was investigated. The effects of combinatorial therapy in terms of cell viability, HSP levels by immunofluorescence and gene expression analysis, oxidative stress generation, and alterations in cellular integrity were evaluated, where combinatorial therapy demonstrated an enhanced therapeutic outcome with maximum glioma cell death. Further, in the murine glioma model, a rapid tumor inhibition of 65 and 53% was observed within 8 days at the primary and secondary tumor sites, respectively, in the MCHT + 17-DMAG group, with abscopal effect-mediated complete tumor inhibition at both the tumor sites within 20 days of MHCT. The extracellularly released HSP90 from dying tumor cells further suggested the induction of immune response supported by the upregulation of IFN-γ and calreticulin genes in the MHCT + 17-DMAG group. Overall, our findings indicate that MHCT activates host immune systems and efficiently cooperates with the HSP90 blockade to inhibit the growth of distant metastatic tumors.

Harnessing Hyperthermia: Molecular, Cellular, and Immunological Insights for Enhanced Anticancer Therapies

Hyperthermia, the raising of tumor temperature (≥39°C), holds great promise as an adjuvant treatment for cancer therapy. This review focuses on 2 key aspects of hyperthermia: its molecular and cellular effects and its impact on the immune system. Hyperthermia has profound effects on critical biological processes. Increased temperatures inhibit DNA repair enzymes, making cancer cells more sensitive to chemotherapy and radiation. Elevated temperatures also induce cell cycle arrest and trigger apoptotic pathways. Furthermore, hyperthermia modifies the expression of heat shock proteins, which play vital roles in cancer therapy, including enhancing immune responses. Hyperthermic treatments also have a significant impact on the body's immune response against tumors, potentially improving the efficacy of immune checkpoint inhibitors. Mild systemic hyperthermia (39°C-41°C) mimics fever, activating immune cells and raising metabolic rates. Intense heat above 50°C can release tumor antigens, enhancing immune reactions. Using photothermal nanoparticles for targeted heating and drug delivery can also modulate the immune response. Hyperthermia emerges as a cost-effective and well-tolerated adjuvant therapy when integrated with immunotherapy. This comprehensive review serves as a valuable resource for the selection of patient-specific treatments and the guidance of future experimental studies.

Latest Advances in the Use of Therapeutic Focused Ultrasound in the Treatment of Pancreatic Cancer

Traditional oncological interventions have failed to improve survival for pancreatic cancer patients significantly. Novel treatment modalities able to release cancer-specific antigens, render immunologically "cold" pancreatic tumours "hot" and disrupt or reprogram the pancreatic tumour microenvironment are thus urgently needed. Therapeutic focused ultrasound exerts thermal and mechanical effects on tissue, killing cancer cells and inducing an anti-cancer immune response. The most important advances in therapeutic focused ultrasound use for initiation and augmentation of the cancer immunity cycle against pancreatic cancer are described. We provide a comprehensive review of the use of therapeutic focused ultrasound for the treatment of pancreatic cancer patients and describe recent studies that have shown an ultrasound-induced anti-cancer immune response in several tumour models. Published studies that have investigated the immunological effects of therapeutic focused ultrasound in pancreatic cancer are described. This article shows that therapeutic focused ultrasound has been deemed to be a safe technique for treating pancreatic cancer patients, providing pain relief and improving survival rates in pancreatic cancer patients. Promotion of an immune response in the clinic and sensitisation of tumours to the effects of immunotherapy in preclinical models of pancreatic cancer is shown, making it a promising candidate for use in the clinic.