Design, synthesis, and biological activity of dual monoamine oxidase A and heat shock protein 90 inhibitors, N-Methylpropargylamine-conjugated 4-isopropylresorcinol for glioblastoma

Dual inhibition of CYP17A1 and HDAC6 by abiraterone-installed hydroxamic acid overcomes temozolomide resistance in glioblastoma through inducing DNA damage and oxidative stress

Glioblastoma (GBM) is a highly aggressive and treatment-resistant brain tumor, necessitating novel therapeutic strategies. In this study, we present a mechanistic breakthrough by designing and evaluating a series of abiraterone-installed hydroxamic acids as potential dual inhibitors of CYP17A1 and HDAC6 for GBM treatment. We established the correlation of CYP17A1/HDAC6 overexpression with tumor recurrence and temozolomide resistance in GBM patients. Compound 12, a dual inhibitor, demonstrated significant anti-GBM activity in vitro, particularly against TMZ-resistant cell lines. Mechanistically, compound 12 induced apoptosis, suppressed recurrence-associated genes, induced oxidative stress and initiated DNA damage response. Furthermore, molecular modeling studies confirmed its potent inhibitory activity against CYP17A1 and HDAC6. In vivo studies revealed that compound 12 effectively suppressed tumor growth in xenograft and orthotopic mouse models without inducing significant adverse effects. These findings highlight the potential of dual CYP17A1 and HDAC6 inhibition as a promising strategy for overcoming treatment resistance in GBM and offer new hope for improved therapeutic outcomes.

HDAC6-Activatable Multifunctional Near-Infrared Probe for Glioma Cell Detection and Elimination

Glioblastoma multiforme (GBM) is a highly aggressive primary brain tumor associated with limited treatment options and high drug resistance, presenting significant challenges in the pursuit of effective treatment strategies. Epigenetic modifications have emerged as promising diagnostic biomarkers and therapeutic targets for GBM. For instance, histone deacetylase 6 (HDAC6) has been identified as a potential pharmacological target for GBM. Furthermore, the overexpression of monoamine oxidase A (MAO A) in glioma has been linked to tumor progression, making it an attractive target for therapy. In this study, we successfully engineered HDAC-MB, an activatable multifunctional small-molecule probe with the goal of efficiently detecting and killing glioma cells. HDAC-MB can be selectively activated by HDAC6, leading to the "turn on" of near-infrared fluorescence and effective inhibition of MAO A, along with potent photodynamic therapy (PDT) effects. Consequently, HDAC-MB not only enables the imaging of HDAC6 in live glioma cells but also exhibits the synergistic effect of MAO A inhibition and PDT, effectively inhibiting glioma invasion and inducing cellular apoptosis. The distinctive combination of features displayed by HDAC-MB positions it as a versatile and highly effective tool for the accurate diagnosis and treatment of glioma cells. This opens up opportunities to enhance therapy outcomes and explore future applications in glioma theranostics.

Small-molecule dual inhibitors targeting heat shock protein 90 for cancer targeted therapy

Heat shock protein 90, also known as Hsp90, is an extensively preserved molecular chaperone that performs a critical function in organizing various biological pathways and cellular operations. As a potential drug target, Hsp90 is closely linked to cancer. Hsp90 inhibitors are a class of drugs that have been extensively studied in preclinical models and have shown promise in a variety of diseases, especially cancer. However, Hsp90 inhibitors have encountered several challenges in clinical development, such as low efficacy, toxicity, or drug resistance, few Hsp90 small molecule inhibitors have been approved worldwide. Nonetheless, combining Hsp90 inhibitors with other tumor inhibitors, such as HDAC inhibitors, tubulin inhibitors, and Topo II inhibitors, has been shown to have synergistic antitumor effects. Consequently, the development of Hsp90 dual-target inhibitors is an effective strategy in cancer treatment, as it enhances potency while reducing drug resistance. This article provides an overview of Hsp90's domain structure and biological functions, as well as a discussion of the design, discovery, and structure-activity relationships of Hsp90 dual inhibitors, aiming to provide insights into clinical drug research from a medicinal chemistry perspective and discover novel Hsp90 dual inhibitors.