Selective and brain-penetrant lanosterol synthase inhibitors target glioma stem-like cells by inducing 24(S),25-epoxycholesterol production

Cholinergic neuron-to-glioblastoma synapses in a human iPSC-derived co-culture model

Glioblastoma (GBM) integrates extensively into brain-wide neuronal circuits; however, neuron-tumor interactions have largely been studied with glutamatergic neurons in animal models. The role of neuromodulatory circuits for GBM biology in all-human cell systems remains unclear. Here, we report a co-culture system employing patient-derived GBM organoids and human induced pluripotent stem cell (hiPSC)-derived cholinergic neurons. We provided evidence of structural human cholinergic synaptic inputs onto GBM cells via trans-monosynaptic tracing and electron microscopy and functional synaptic interactions through the metabotropic CHRM3 receptor via calcium imaging. Deep single-cell RNA sequencing of co-cultures compared to GBM monocultures further revealed shifts in tumor transcriptional profiles toward a more proliferative state, with contributions from both diffusible factors and direct contacts, the latter of which are dependent on cholesterol biosynthesis. Together, our findings support the role of cholinergic inputs in promoting GBM progression and highlight hiPSC-derived co-culture models as a useful platform for cancer neuroscience.

Multiscale analysis and optimal glioma therapeutic candidate discovery using the CANDO platform

Glioma is a highly malignant brain tumor with limited treatment options. We employed the Computational Analysis of Novel Drug Opportunities (CANDO) platform for multiscale therapeutic discovery to predict new glioma therapies. We began by computing interaction scores between extensive libraries of drugs/compounds and proteins to generate "interaction signatures" that model compound behavior on a proteomic scale. Compounds with signatures most similar to those of drugs approved for a given indication were considered potential treatments. These compounds were further ranked by degree of consensus in corresponding similarity lists. We benchmarked performance by measuring the recovery of approved drugs in these similarity and consensus lists at various cutoffs, using multiple metrics and compari ng results to random controls and performance across all indications. Compounds ranked highly by consensus but not previously associated with the indication of interest were considered new predictions. Our benchmarking results showed that CANDO improved accuracy in identifying glioma-associated drugs across all cutoffs compared to random controls. Our predictions, supported by literature-based analysis, identified 23 potential glioma treatments, including approved drugs like vitamin D, taxanes, vinca alkaloids, topoisomerase inhibitors, and folic acid, as well as investigational compounds such as ginsenosides, chrysin, resiniferatoxin, and cryptotanshinone. Further functional annotation-based analysis of the top targets with the strongest interactions to these predictions identified Vitamin D3 receptor, thyroid hormone receptor, acetylcholinesterase, cyclin-dependent kinase 2, tubulin alpha chain, dihydrofolate reductase, and thymidylate synthase. These findings indicate that CANDO's multitarget, multiscale framework is effective in identifying glioma drug candidates thereby informing new strategies for improving treatment.

Thermal proteome profiling and proteome analysis using high-definition mass spectrometry demonstrate modulation of cholesterol biosynthesis by next-generation galeterone analog VNPP433-3β in castration-resistant prostate cancer

Cholesterol (CHOL) homeostasis is significantly modulated in prostate cancer (PCa) suggesting an active role in PCa development and progression. Several studies indicate a strong correlation between elevated CHOL levels and increased PCa risk and severity. Inhibition of CHOL biosynthesis at different steps, including lanosterol synthase (LSS), has shown significant efficacy against both hormone-dependent and castration-resistant PCa. Earlier, we reported proteasomal degradation of androgen receptor (AR)/AR-Vs and Mnk1/2 as the primary mechanisms of action of VNPP433-3β in inhibiting PCa cell proliferation and tumor growth. Through thermal proteome profiling, comparative proteomics and cellular thermal shift assay, we identified VNPP433-3β's ancillary effect of lowering CHOL by binding to LSS and lanosterol 14-alpha demethylase, potentially inhibiting CHOL biosynthesis in PCa cells and tumors. Additionally, in conjunction with our previously reported transcriptome analysis, proteomics reveals that VNPP433-3β modulated upstream regulators and pathways critical for PCa stem cell maintenance and recurrence. The inhibition of CHOL biosynthesis by VNPP433-3β reinforces its multifaceted effects in PCa across all stages, highlighting its potential as a single-agent therapy. Achieving reduced CHOL levels aligns with better treatment outcomes, further substantiating VNPP433-3β's therapeutic potential.

Multidimensional Uses of Bitter Melon (Momordica charantia L.) Considering the Important Functions of its Chemical Components

Bitter melon (Momordica charantia L.) is a member of the Cucurbitaceae, which is also known as bitter squash, bitter gourd, karela, Goya melon and balsam pear. It is a rich source of different vitamins, potassium, zinc and other nutrients. The main pharmaceutical benefits of bitter melon are "antiinflammatory", "antioxidant activity", "antimicrobial characteristic", "anticancer activity", and "antihelmintic activity", "antidiabetic effects", "antiinflammation activity" and "treat skin conditions". Its fruit is the main part of the plant which has been used for medicinal and food purposes. The primary metabolites in bitter gourd are common sugars, chlorophyll and proteins while secondary metabolites are carotenoids, alkaloids, phenolics, curcubitane triterpenoids, saponins, etc. The present review aims to study and survey on the nearly up-to-date results and findings regarding the pharmaceutical advantages and health benefits of bitter melon in an organic life.

Novel benzenesulfonamides as dual VEGFR2/FGFR1 inhibitors targeting breast cancer: Design, synthesis, anticancer activity and in silico studies

In the current study, a new series of benzenesulfonamides 6a-r was designed and synthesized as dual VEGFR-2 and FGFR1 kinase inhibitors with anti-cancer activity. The 4-trifluoromethyl benzenesulfonamide 6l exhibited the highest dual VEGFR-2/FGFR1 inhibitory activity with IC50 values of 0.025 and 0.026 µM, respectively. It showed a higher activity than sorafenib and staurosporine by 1.8- and 1.3-fold, respectively. Furthermore, compound 6l was further tested on EGFR and PDGFR-β kinases showing IC50 values of 0.106 and 0.077 µM, respectively. The target compounds were tested for their anticancer activity against NCI-60 panel of cancer cell lines at 10 µM concentration, where compound 6l displayed the highest mean growth inhibition percent % (GI%) of 60.38%. Compounds 6a, 6b, 6e, 6f, 6h-l, and 6n-r revealed promising GI% on breast cancer cell lines (MCF-7, T-47D, and MDA-MB-231), and were subjected to IC50 determination on these cell lines. The tested compounds showed a higher activity on T-47D and MCF-7 cell lines over MDA-MB-231 cell line compared to the used reference standard; sorafenib. Compounds 6e, 6h-j, 6l and 6o revealed IC50 values ≤ 20 µM against T-47D cell line, furthermore, they were found to be non-cytotoxic on Vero normal cell line. Furthermore, the effect of the most active compounds 6i, and 6l in T-47D cells on cell cycle analysis progression, cell apoptosis, and apoptosis markers was investigated. Both compounds arrested cell cycle progression at G1 phase, furthermore, they enhanced early and late apoptosis, as well as necrosis. The capability of compounds 6i, and 6l to induce apoptosis was further confirmed by their ability to raise BAX/BCl-2 ratio and caspase-3 level in the treated cells. Cell migration assay revealed that both compounds 6i and 6l have anti-migratory effects compared to control T-47D cells after 24, and 48 h. Molecular docking studies for compounds 6a-r on VEGFR-2 and FGFR1 binding sites showed that they exhibit an analogous binding mode in both target kinases which agrees with that of type II kinase inhibitors.

Synergistic Effects of PARP Inhibition and Cholesterol Biosynthesis Pathway Modulation

An in-depth multiomic molecular characterization of PARP inhibitors revealed a distinct poly-pharmacology of niraparib (Zejula) mediated by its interaction with lanosterol synthase (LSS), which is not observed with other PARP inhibitors. Niraparib, in a similar way to the LSS inhibitor Ro-48-8071, induced activation of the 24,25-epoxysterol shunt pathway, which is a regulatory signaling branch of the cholesterol biosynthesis pathway. Interestingly, the combination of an LSS inhibitor with a PARP inhibitor that does not bind to LSS, such as olaparib, had an additive effect on killing cancer cells to levels comparable with niraparib as a single agent. In addition, the combination of PARP inhibitors and statins, inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, an enzyme catalyzing the rate-limiting step in the mevalonate pathway, had a synergistic effect on tumor cell killing in cell lines and patient-derived ovarian tumor organoids. These observations suggest that concomitant inhibition of the cholesterol biosynthesis pathway and PARP activity might result in stronger efficacy of these inhibitors against tumor types highly dependent on cholesterol metabolism.

SIGNIFICANCE

The presented data indicate, to our knowledge, for the first time, the potential benefit of concomitant modulation of cholesterol biosynthesis pathway and PARP inhibition and highlight the need for further investigation to assess its translational relevance.

Inhibition of DUSP18 impairs cholesterol biosynthesis and promotes anti-tumor immunity in colorectal cancer

Tumor cells reprogram their metabolism to produce specialized metabolites that both fuel their own growth and license tumor immune evasion. However, the relationships between these functions remain poorly understood. Here, we report CRISPR screens in a mouse model of colo-rectal cancer (CRC) that implicates the dual specificity phosphatase 18 (DUSP18) in the establishment of tumor-directed immune evasion. Dusp18 inhibition reduces CRC growth rates, which correlate with high levels of CD8+ T cell activation. Mechanistically, DUSP18 dephosphorylates and stabilizes the USF1 bHLH-ZIP transcription factor. In turn, USF1 induces the SREBF2 gene, which allows cells to accumulate the cholesterol biosynthesis intermediate lanosterol and release it into the tumor microenvironment (TME). There, lanosterol uptake by CD8+ T cells suppresses the mevalonate pathway and reduces KRAS protein prenylation and function, which in turn inhibits their activation and establishes a molecular basis for tumor cell immune escape. Finally, the combination of an anti-PD-1 antibody and Lumacaftor, an FDA-approved small molecule inhibitor of DUSP18, inhibits CRC growth in mice and synergistically enhances anti-tumor immunity. Collectively, our findings support the idea that a combination of immune checkpoint and metabolic blockade represents a rationally-designed, mechanistically-based and potential therapy for CRC.

Discovery and Optimization of N-Arylated Tetracyclic Dicarboximides That Target Primary Glioma Stem-like Cells

We recently discovered a novel N-aryl tetracyclic dicarboximide MM0299 (1) with robust activity against glioma stem-like cells that potently and selectively inhibits lanosterol synthase leading to the accumulation of the toxic shunt metabolite 24(S),25-epoxycholesterol. Herein, we delineate a systematic and comprehensive SAR study that explores the structural space surrounding the N-aryl tetracyclic dicarboximide scaffold. A series of 100 analogs were synthesized and evaluated for activity against the murine glioma stem-like cell line Mut6 and for metabolic stability in mouse liver S9 fractions. This study led to several analogs with single-digit nanomolar activity in Mut6 glioblastoma cells that were metabolically stable in S9 fractions. In vivo pharmacokinetic analysis of selected analogs identified compound 52a (IC50 = 63 nM; S9 T1/2 > 240 min) which was orally available (39% plasma; 58% brain) and displayed excellent brain exposure. Chronic oral dosing of 52a during a 2-week tolerability study indicated no adverse effect on body weight nor signs of hematologic, liver, or kidney toxicity.

Chemical Inhibition of Sterol Biosynthesis

Cholesterol is an essential molecule of life, and its synthesis can be inhibited by both genetic and nongenetic mechanisms. Hundreds of chemicals that we are exposed to in our daily lives can alter sterol biosynthesis. These also encompass various classes of FDA-approved medications, including (but not limited to) commonly used antipsychotic, antidepressant, antifungal, and cardiovascular medications. These medications can interfere with various enzymes of the post-lanosterol biosynthetic pathway, giving rise to complex biochemical changes throughout the body. The consequences of these short- and long-term homeostatic disruptions are mostly unknown. We performed a comprehensive review of the literature and built a catalogue of chemical agents capable of inhibiting post-lanosterol biosynthesis. This process identified significant gaps in existing knowledge, which fall into two main areas: mechanisms by which sterol biosynthesis is altered and consequences that arise from the inhibitions of the different steps in the sterol biosynthesis pathway. The outcome of our review also reinforced that sterol inhibition is an often-overlooked mechanism that can result in adverse consequences and that there is a need to develop new safety guidelines for the use of (novel and already approved) medications with sterol biosynthesis inhibiting side effects, especially during pregnancy.

Cholesterol Metabolism in Pancreatic Cancer

Pancreatic cancer's substantial impact on cancer-related mortality, responsible for 8% of cancer deaths and ranking fourth in the US, persists despite advancements, with a five-year relative survival rate of only 11%. Forecasts predict a 70% surge in new cases and a 72% increase in global pancreatic cancer-related deaths by 2040. This review explores the intrinsic metabolic reprogramming of pancreatic cancer, focusing on the mevalonate pathway, including cholesterol biosynthesis, transportation, targeting strategies, and clinical studies. The mevalonate pathway, central to cellular metabolism, significantly shapes pancreatic cancer progression. Acetyl coenzyme A (Acetyl-CoA) serves a dual role in fatty acid and cholesterol biosynthesis, fueling acinar-to-ductal metaplasia (ADM) and pancreatic intraepithelial neoplasia (PanIN) development. Enzymes, including acetoacetyl-CoA thiolase, 3-hydroxy-3methylglutaryl-CoA (HMG-CoA) synthase, and HMG-CoA reductase, are key enzymes in pancreatic cancer. Inhibiting HMG-CoA reductase, e.g., by using statins, shows promise in delaying PanIN progression and impeding pancreatic cancer. Dysregulation of cholesterol modification, uptake, and transport significantly impacts tumor progression, with Sterol O-acyltransferase 1 (SOAT1) driving cholesterol ester (CE) accumulation and disrupted low-density lipoprotein receptor (LDLR) expression contributing to cancer recurrence. Apolipoprotein E (ApoE) expression in tumor stroma influences immune suppression. Clinical trials targeting cholesterol metabolism, including statins and SOAT1 inhibitors, exhibit potential anti-tumor effects, and combination therapies enhance efficacy. This review provides insights into cholesterol metabolism's convergence with pancreatic cancer, shedding light on therapeutic avenues and ongoing clinical investigations.

Inducible mismatch repair streamlines forward genetic approaches to target identification of cytotoxic small molecules

Orphan cytotoxins are small molecules for which the mechanism of action (MoA) is either unknown or ambiguous. Unveiling the mechanism of these compounds may lead to useful tools for biological investigation and in some cases, new therapeutic leads. In select cases, the DNA mismatch repair-deficient colorectal cancer cell line, HCT116, has been used as a tool in forward genetic screens to identify compound-resistant mutations, which have ultimately led to target identification. To expand the utility of this approach, we engineered cancer cell lines with inducible mismatch repair deficits, thus providing temporal control over mutagenesis. By screening for compound resistance phenotypes in cells with low or high rates of mutagenesis, we increased both the specificity and sensitivity of identifying resistance mutations. Using this inducible mutagenesis system, we implicate targets for multiple orphan cytotoxins, including a natural product and compounds emerging from a high-throughput screen, thus providing a robust tool for future MoA studies.