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Epigenetic mutations like aberrant DNA methylation, histone modifications, or RNA silencing are found in a number of human diseases. This review article discusses the epigenetic mechanisms involved in neurodegenerative disorders, cardiovascular disorders, auto-immune disorder, and genomic imprinting disorders. In addition, emerging epigenetic therapeutic strategies for the treatment of such disorders are presented. Medicinal chemistry campaigns highlighting the efforts of the chemists invested towards the rational design of small molecule inhibitors have also been included. Pleasingly, several classes of epigenetic inhibitors, DNMT, HDAC, BET, HAT, and HMT inhibitors along with RNA based therapies have exhibited the potential to emerge as therapeutics in the longer run. It is quite hopeful that epigenetic modulator-based therapies will advance to clinical stage investigations by leaps and bounds.

Supplementary data includes IC50 of SAHA and B390 (S1),bioinformatic analysis (S2 and S3), and tumor size (S4)

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer characterized by early dissemination and poor drug response. Therefore, it is an unmet medical need to develop new strategies for treatment. As aberrant activation of ERK due to KRAS activating mutation is a driving force for PDAC, a brake system that can terminate ERK signaling represents an ideal druggable target. Herein, we demonstrate that forced expression of dual specificity phosphatase-2 (DUSP2), a specific ERK phosphatase, abrogated tumor formation and loss of Dusp2 facilitated Kras-driven PDAC progression. We report that a selective HDAC1/2 inhibitor (B390) has multifaceted therapeutic potential in PDAC by restoring the expression and function of DUSP2. In vitro study showed that treatment with B390 inhibited growth and migration abilities of PDAC cells, decreased extracellular vesicle-associated VEGF-C expression, and suppressed lymphatic endothelial cell proliferation. In vivo, B390 not only suppressed tumor growth by increasing tumor cell death, it also inhibited lymphangiogenesis and lymphovascular invasion. Taken together, our data demonstrate that B390 was able to alleviate loss of DUSP2-mediated pathologic processes, which provides the proof-of-concept evidence to demonstrate the potential of using selective HDAC1/2 inhibitors in PDAC treatment and suggests reinstating DUSP2 expression may be a strategy to subside PDAC progression.

PDF - 361KB, Supplementary Materials and Methods; Table S1: Primary Antibodies and secondary antibodies; Figure S1: Effect of MPT0B098 on the organizations of cellular microtubule network; Figure S2: Effect of MPT0B098 on HIF-regulated genes in A549 cells; Figure S3: MPT0B098 inhibits HuR translocation from the nucleus to the cytoplasm in HONE-1 and PC3 cells.

Microtubule inhibitors have been shown to inhibit hypoxia-inducible factor-1α (HIF-1α) expression through inhibition translation or enhancing protein degradation. Little is known of the effect of microtubule inhibitors on the stability of HIF-1α mRNA. We recently discovered a novel indoline–sulfonamide compound, 7-aryl-indoline-1-benzene-sulfonamide (MPT0B098), as a potent microtubule inhibitor through binding to the colchicine-binding site of tubulin. MPT0B098 is active against the growth of various human cancer cells, including chemoresistant cells with IC50 values ranging from 70 to 150 nmol/L. However, normal cells, such as human umbilical vein endothelial cells (HUVEC), exhibit less susceptibility to the inhibitory effect of MPT0B098 with IC50 of 510 nmol/L. Similar to typical microtubule inhibitors, MPT0B098 arrests cells in the G2–M phase and subsequently induces cell apoptosis. In addition, MPT0B098 effectively suppresses VEGF-induced cell migration and capillary-like tube formation of HUVECs. Distinguished from other microtubule inhibitors, MPT0B098 not only inhibited the expression levels of HIF-1α protein but also destabilized HIF-1α mRNA. The mechanism of causing unstable of HIF-1α mRNA by MPT0B098 is through decreasing RNA-binding protein, HuR, translocation from the nucleus to the cytoplasm. Notably, MPT0B098 effectively suppresses tumor growth and microvessel density of tumor specimens in vivo. Taken together, our results provide a novel mechanism of inhibiting HIF-1α of a microtubule inhibitor MPT0B098. MPT0B098 is a promising anticancer drug candidate with potential for the treatment of human malignancies. Mol Cancer Ther; 12(7); 1202–12. ©2013 AACR.

Table S1. CSC frequency measured by ELDA in vitro. Table S2. Multiple corrections for correlation p value. Table S3. Tumor incidence in limiting dilution assay (I). Table S4. Tumor incidence in limiting dilution assay (II). Table S5. Top 10 list of candidate drugs exert similar actions like DUSP2. Table S6: IC50 of B369, B390, and SAHA determined by different methods.

HDACi abolished hypoxia-induced cancer malignancy

PDF file - 72KB, Combination index (CI) values of sorafenib in combination with MPT0E028 or vorinostat in liver cancer cells.

PDF file - 1056KB, Investigation of the mechanism underlying sorafenibcaused p21 attenuation.

PDF file - 60KB, Primer sequences for real-time PCR used in this study.

Legends for supplementary figures S1-S7

Cancer stem-like cells (CSC) evolve to overcome the pressures of reduced oxygen, nutrients or chemically induced cell death, but the mechanisms driving this evolution are incompletely understood. Here, we report that hypoxia-mediated downregulation of the dual specificity phosphatase 2 (DUSP2) is critical for the accumulation of CSC in colorectal cancer. Reduced expression of DUSP2 led to overproduction of COX-2–derived prostaglandin E2, which promoted cancer stemness via the EP2/EP4 signaling pathways. Genetic and pharmacological inhibition of PGE2 biosynthesis or signal transduction ameliorated loss-of-DUSP2–induced tumor growth and cancer stemness. Genome-wide profile analysis revealed that genes regulated by DUSP2 were similar to those controlled by histone deacetylase. Indeed, treatment with novel histone deacetylase inhibitors abolished hypoxia-induced DUSP2 downregulation, COX-2 overexpression, cancer stemness, tumor growth, and drug resistance. Our findings illuminate mechanisms of cancer stemness and suggest new cancer therapy regimens. Cancer Res; 77(16); 4305–16. ©2017 AACR.

Effect of MPT0L145 on autophagosome formation.

Figure S3: PGE2 mediates loss-of-DUSP2-induced cancer stemness. Figure S4: Hypoxia-induced COX-2 expression is mediated by downregulation of DUSP2.

Supplementary Fig. S1, Time-dependent effects of BGJ398 on autophagy in bladder cancer cells. Supplementary Figure. S2. In vitro inhibitory effects of MPT0L145 and SAR405 on PIK3C3 (VPS34). Supplementary Figure. S3. A and B, The potentiation of MPT0L145-increased cytotoxicity by PIK3C3 knockdown in Panc1 and A2780 cells. C and D, ROS inhibitors partially reversed MPT0L145-decreased cell viability. Supplementary Figure S4. Validation of ATG5-knockout (K.O.) RT-112 cells. Supplementary Fig. S5. A, Effect of specific CSF1R inhibitor, BLZ945, on the viability in RT-112 and RT-4 cells. B, Dual inhibition of FGFR3 signaling and autophagy by MPT0L145. C, Effect of MPT0L145 on necrosis in bladder cancer cells.

PDF file - 90KB

Supplementary Table S1. In vitro inhibitory effects of MPT0L145 on a panel of lipid kinases. Supplementary Table S2. Binding kinetics and affinity of MPT0L145 to wildtype and mutant PIK3C3.

PDF file - 1305KB, Antitumor activity of MPT0E028 plus sorafenib in a Hep3B xenograft model.

PDF file - 1063KB, Synergistic interaction between MPT0E028 and vorinostat in Hep3B cells.

PDF file - 51KB, Differential cytotoxic effects of sorafenib, MPT0E028 and vorinostat on different liver cancer cell lines.

Purpose: MPT0L145 has been developed as a FGFR inhibitor exhibiting significant anti-bladder cancer activity in vitro and in vivo via promoting autophagy-dependent cell death. Here, we aim to elucidate the underlying mechanisms.Experimental Design: Autophagy flux, morphology, and intracellular organelles were evaluated by Western blotting, transmission electron microscope, and fluorescence microscope. Molecular docking and surface plasmon resonance assay were performed to identify drug–protein interaction. Lentiviral delivery of cDNA or shRNA and CRISPR/Cas9-mediated genome editing was used to modulate gene expression. Mitochondrial oxygen consumption rate was measured by a Seahorse XFe24 extracellular flux analyzer, and ROS level was measured by flow cytometry.Results: MPT0L145 persistently increased incomplete autophagy and phase-lucent vacuoles at the perinuclear region, which were identified as enlarged and alkalinized late-endosomes. Screening of a panel of lipid kinases revealed that MPT0L145 strongly inhibits PIK3C3 with a Kd value of 0.53 nmol/L. Ectopic expression of PIK3C3 reversed MPT0L145-increased cell death and incomplete autophagy. Four residues (Y670, F684, I760, D761) at the ATP-binding site of PIK3C3 are important for the binding of MPT0L145. In addition, MPT0L145 promotes mitochondrial dysfunction, ROS production, and DNA damage, which may in part, contribute to cell death. ATG5-knockout rescued MPT0L145-induced cell death, suggesting simultaneous induction of autophagy is crucial to its anticancer activity. Finally, our data demonstrated that MPT0L145 is able to overcome cisplatin resistance in bladder cancer cells.Conclusions: MPT0L145 is a first-in-class PIK3C3/FGFR inhibitor, providing an innovative strategy to design new compounds that increase autophagy, but simultaneously perturb its process to promote bladder cancer cell death. Clin Cancer Res; 24(5); 1176–89. ©2017 AACR.

PDF file - 1939KB, Effects of sorafenib in combination with MPT0E028 on cell proliferation, viability and LDH activity in liver cancer cell lines.

Background Glioblastoma (GBM) is the most aggressive and lethal brain tumor. Although the histone deacetylase (HDAC)/transcription factor axis promotes growth in GBM, whether HDACs including HDAC6 are involved in modulating long non-coding RNAs (lncRNAs) to affect GBM malignancy remains obscure. Methods Integrative analysis of microarray and RNA-seq was performed to identify lncRNAs governed by HDAC6. Half-life measurement and RNA-protein pull-down assay combined with isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomic analysis were conducted to identify RNA modulators. The effect of LINC00461 on GBM malignancy was evaluated using animal models and cell proliferation-related assays. Functional analysis of the LINC00461 downstream networks was performed comprehensively using ingenuity pathway analysis and public databases. Results We identified a lncRNA, LINC00461, which was substantially increased in stem-like/treatment-resistant GBM cells. LINC00461 was inversely correlated with the survival of mice-bearing GBM and it was stabilized by the interaction between HDAC6 and RNA-binding proteins (RBPs) such as carbon catabolite repression—negative on TATA-less (CCR4-NOT) core exoribonuclease subunit 6 and fused in sarcoma. Targeting LINC00461 using azaindolylsulfonamide, an HDAC6 inhibitor, decreased cell-division-related proteins via the lncRNA-microRNA (miRNA)-mRNA networks and caused cell-cycle arrest, thereby suppressing proliferation in parental and drug-resistant GBM cells and prolonging the survival of mice-bearing GBM. Conclusions This study sheds light on the role of LINC00461 in GBM malignancy and provides a novel therapeutic strategy for targeting the HDAC6/RBP/LINC00461 axis and its downstream effectors in patients with GBM.

Pragmatic insertion of pargyline, a LSD1 inhibitor, as a surface recognition part in the HDAC inhibitory pharmacophore was planned in pursuit of furnishing potent antiprostate cancer agents. Resultantly, compound

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive cancer characterized by early dissemination and poor drug response. Therefore, it is an unmet medical need to develop new strategies for treatment. As aberrant activation of ERK due to KRAS activating mutation is a driving force for PDAC, a brake system that can terminate ERK signaling represents an ideal druggable target. Herein, we demonstrate that forced expression of dual specificity phosphatase-2 (DUSP2), a specific ERK phosphatase, abrogated tumor formation and loss of Dusp2 facilitated Kras-driven PDAC progression. We report that a selective HDAC1/2 inhibitor (B390) has multifaceted therapeutic potential in PDAC by restoring the expression and function of DUSP2. In vitro study showed that treatment with B390 inhibited growth and migration abilities of PDAC cells, decreased extracellular vesicle-associated VEGF-C expression, and suppressed lymphatic endothelial cell proliferation. In vivo, B390 not only suppressed tumor growth by increasing tumor cell death, it also inhibited lymphangiogenesis and lymphovascular invasion. Taken together, our data demonstrate that B390 was able to alleviate loss of DUSP2-mediated pathologic processes, which provides the proof-of-concept evidence to demonstrate the potential of using selective HDAC1/2 inhibitors in PDAC treatment and suggests reinstating DUSP2 expression may be a strategy to subside PDAC progression.

Glioblastoma (GBM) is a highly malignant brain tumor characterized by a heterogeneous population of genetically unstable and highly infiltrative cells that are resistant to chemotherapy. Although substantial efforts have been invested in the field of anti-GBM drug discovery in the past decade, success has primarily been confined to the preclinical level, and clinical studies have often been hampered due to efficacy-, selectivity-, or physicochemical property-related issues. Thus, expansion of the list of molecular targets coupled with a pragmatic design of new small-molecule inhibitors with central nervous system (CNS)-penetrating ability is required to steer the wheels of anti-GBM drug discovery endeavors. This Perspective presents various aspects of drug discovery (challenges in GBM drug discovery and delivery, therapeutic targets, and agents under clinical investigation). The comprehensively covered sections include the recent medicinal chemistry campaigns embarked upon to validate the potential of numerous enzymes/proteins/receptors as therapeutic targets in GBM.

A fragment recruitment process was conducted to pinpoint a suitable fragment for installation in the HDAC inhibitory template to furnish agents endowed with the potential to treat lung cancer. Resultantly, Ring C expanded deoxyvasicinone was selected as an appropriate surface recognition part that was accommodated in the HDAC three-component model. Delightfully, fused quinazolinone 6 demonstrating a magnificent anticancer profile against KRAS and EGFR mutant lung cancer cell lines (IC

Background: Quinoline is considered to be a privileged heterocyclic ring owing to its presence in diverse scaffolds endowed with promising activity profiles. In particular, quinoline containing compounds have exhibited substantial antiproliferative effects through the diverse mechanism of actions, which indicates that the heteroaryl unit is flexible as well as accessible to subtle structural changes that enable its inclusion in chemically distinct anti-tumor constructs. Methods: Herein, we describe a medicinal chemistry perspective on quinolines as anticancer agents by digging into the peer-reviewed literature as well as patents published in the past few years. Results: This review will serve as a guiding tool for medicinal chemists and chemical biologists to gain insights about the benefits of quinoline ring installation to tune the chemical architectures for inducing potent anticancer effects. Conclusion: Quinoline ring containing anticancer agents presents enough optimism and promise in the field of drug discovery to motivate the researchers towards the continued explorations on such scaffolds. It is highly likely that adequate efforts in this direction might yield some potential cancer therapeutics in the future.

Polygonatum odoratum is a perennial rhizomatous medicinal plant and different plant parts have been used in the treatment of various ailments. Herein, we have investigated the structural compositions of rhizome, leaf, and stem cell walls. We found 30–44% of polysaccharides in these wall preparations were cyclohexanediaminetetraacetic acid (CDTA) extractable, the proportion of heteromannans (HMs) in the rhizome is nearly three-fold compared to that of the leave and stem. The pectic polysaccharides of the rhizome are also structurally more diverse, with arabinans and type I and type II arabinogalactans being richest as shown by linkage study of the sodium carbonate (Na2CO3) extract. In addition, the 2-linked Araf was rhizome-specific, suggesting the cell walls in the rhizome had adapted to a more complex structure compared to that of the leaf and stem. Water-soluble polysaccharide fractions were also investigated, high proportion of Man as in 4-linked Manp indicated high proportion of HMs. The 21.4 kDa pectic polysaccharides and HMs derived from rhizome cell walls induced specific immune response in mice macrophage cells producing IL-1α and hematopoietic growth factors GM-CSF and G-CSF in vitro. QC 20221012

BackgroundChronic obstructive pulmonary disease (COPD) is a major cause of chronic mortality. The objective of this study was to investigate the therapeutic potential of a novel potent histone deacetylase (HDAC) inhibitor MPT0E028 on emphysema.Materials and MethodsA mouse model of porcine pancreatic elastase (PPE)-induced emphysema was orally administered 0, 25, or 50 mg/kg body weight (BW) of the MPT0E028 five times/week for 3 weeks. Pulmonary function, mean linear intercept (MLI), chest CT, inflammation, yes-associated protein (YAP), transcriptional coactivator with PDZ-binding motif (TAZ), surfactant protein C (SPC), T1-α, p53, and sirtuin 1 (SIRT1) levels were examined.Results50 mg/kg BW of the MPT0E028 significantly decreased the tidal volume in emphysematous mice (p < 0.05). Emphysema severity was significantly reduced from 26.65% (PPE only) to 13.83% (50 mg/kg BW of the MPT0E028). Total cell counts, neutrophils, lymphocytes, and eosinophils significantly decreased with both 25 and 50 mg/kg BW of the MPT0E028 (p < 0.05). Also, 50 mg/kg BW of the MPT0E028 significantly decreased the levels of KC, TNF-α, and IL-6 in lung tissues and serum (p < 0.05). Expressions of p-TAZ/TAZ in lung tissues significantly decreased with 50 mg/kg BW of the MPT0E028 (p < 0.05). Expressions of p53 significantly decreased in alveolar regions with 50 mg/kg BW of the MPT0E028 (p < 0.05), and the expression of SPC increased in alveolar regions with 50 mg/kg BW of the MPT0E028 (p < 0.05).ConclusionsOur study showed that the potent HDAC inhibitor MPT0E028 reduced the severity and inflammation of emphysema with improvement in lung function, which could be regulated by Hippo signaling pathway. The MPT0E028 may have therapeutic potential for emphysema.

A series of 3-subsituted quinolinehydroxamic acids has been synthesised and evaluated for their effect on human lung cancer cell line (A549), human colorectal cancer cell line (HCT116) and HDAC isoforms 1, 2, 6, and 8. The results indicated that substitution at C3 of quinoline is favoured for HDAC6 selectivity. Two compounds (25 and 26) were also found to be potent anti-proliferative compounds with IC50 values ranging from 1.29 to 2.13 µM against A549 and HCT116 cells. These compounds displayed remarkable selectivity for HDAC6 over other HDAC isoforms with nanomolar IC50 values. Western blot analysis revealed that compounds of this series activate apoptotic caspase pathway as indicated by cleavage of caspase 3, 8, and 9 and also increase phosphorylated H2AX thus inducing DNA double strand fragmentation in a concentration dependent manner. Flow cytometric analysis also displayed a dose dependent increase of cell population in sub G1 phase., Graphical Abstract

Background Glioblastoma is associated with poor prognosis and high mortality. Although the use of first-line temozolomide can reduce tumor growth, therapy-induced stress drives stem cells out of quiescence, leading to chemoresistance and glioblastoma recurrence. The specificity protein 1 (Sp1) transcription factor is known to protect glioblastoma cells against temozolomide; however, how tumor cells hijack this factor to gain resistance to therapy is not known. Methods Sp1 acetylation in temozolomide-resistant cells and stemlike tumorspheres was analyzed by immunoprecipitation and immunoblotting experiments. Effects of the histone deacetylase (HDAC)/Sp1 axis on malignant growth were examined using cell proliferation–related assays and in vivo experiments. Furthermore, integrative analysis of gene expression with chromatin immunoprecipitation sequencing and the recurrent glioblastoma omics data were also used to further determine the target genes of the HDAC/Sp1 axis. Results We identified Sp1 as a novel substrate of HDAC6, and observed that the HDAC1/2/6/Sp1 pathway promotes self-renewal of malignancy by upregulating B cell-specific Mo-MLV integration site 1 (BMI1) and human telomerase reverse transcriptase (hTERT), as well as by regulating G2/M progression and DNA repair via alteration of the transcription of various genes. Importantly, HDAC1/2/6/Sp1 activation is associated with poor clinical outcome in both glioblastoma and low-grade gliomas. However, treatment with azaindolyl sulfonamide, a potent HDAC6 inhibitor with partial efficacy against HDAC1/2, induced G2/M arrest and senescence in both temozolomide-resistant cells and stemlike tumorspheres. Conclusion Our study uncovers a previously unknown regulatory mechanism in which the HDAC6/Sp1 axis induces cell division and maintains the stem cell population to fuel tumor growth and therapeutic resistance.

Bladder cancer is the second most common genitourinary malignancy in the world. However, only immune-checkpoint inhibitors and erdafitinib are available to treat advanced bladder cancer. Our previous study reported that 4-((4-(4-ethylpiperazin-1-yl) phenyl)amino)-N-(3,4,5-trichlorophenyl)-7H-pyrrolo-[2, 3-d]pyrimidine-7-carboxamide hydrochloride (13i HCl) is a potent CK1δ inhibitor showing significant anti-bladder cancer activity. In this study, we elucidated the pharmacological mechanisms underlying 13i HCl's inhibition of human bladder cancer. Our results demonstrate that expression of the CSNK1D gene, which codes for CK1δ, is upregulated in superficial and infiltrating bladder cancer patients in two independent datasets. CK1δ knockdown decreased β-catenin expression in bladder cancer cells and inhibited their growth. Additionally, 13i HCl suppressed bladder cancer cell proliferation and increased apoptosis. We also observed that inhibition of CK1δ using 13i HCl or PF-670462 triggers necroptosis in bladder cancer cells. Finally, 13i HCl inhibited bladder cancer cell migration and reversed their mesenchymal characteristics. These findings suggest further development of 13i HCl as a potential therapeutic agent to treat bladder cancer is warranted.

Introduction: Anaplastic lymphoma kinase (ALK), a receptor tyrosine kinase, has been discovered in several cancers, including anaplastic large-cell lymphoma, non-small cell lung cancer, and inflammatory myofibroblastic tumors. The deregulation of ALK activities, such as translocation and point mutation, results in human carcinogenesis. The use of ALK inhibitors in clinical cancer treatment has been shown to be efficacious, and the issue of resistance to ALK inhibitors has been reported. Consequently, the development of a new generation of ALK inhibitors is necessary.Areas covered: This paper provides a comprehensive review of the patent literature from 2014 to 2018 including small molecule ALK inhibitors and their use as anticancer agents. The approved and developing ALK inhibitors are described.Expert commentary: The available three generations of ALK inhibitors have shown a good anticancer effect in ALK-positive non-small cell lung cancer. An urgent issue in this field is ALK resistance development. The development of new ALK inhibitors through structure modification of currently available ALK inhibitors is proceeding, such as the synthesis of macrocyclic compounds. This article arranges the ALK inhibitors that have published in the patent in recent years. It may help in the investigation of a new generation of ALK inhibitors, which can overcome the resistance issue and development of novel drug candidates in the future.

Background: Histone deacetylase (HDAC) inhibitors have emerged as a new class of anti-tumor agents for various types of tumors, including glioblastoma. Methods and results: We found that a novel HDAC inhibitor, MPT0B291, significantly reduced the cell viability and increased cell death of human and rat glioma cell lines, but not in normal astrocytes. We also demonstrated that MPT0B291 suppressed proliferation by inducing G1 phase cell cycle arrest and increased apoptosis in human and rat glioma cell lines by flow cytometry and immunocytochemistry. We further investigated the anti-tumor effects of MPT0B291 in xenograft (mouse) and allograft (rat) models. The IVIS200 images and histological analysis indicated MPT0B291 (25 mg/kg, p. o.) reduced tumor volume. Mechanistically, MPT0B291 increased phosphorylation and acetylation/activation of p53 and increased mRNA levels of the apoptosis related genes PUMA, Bax, and Apaf1 as well as increased protein level of PUMA, Apaf1 in C6 cell line. The expression of cell cycle related gene p21 was also increased and Cdk2, Cdk4 were decreased by MPT0B291. Conclusion: Our study highlights the anti-tumor efficacy of a novel compound MPT0B291 on glioma growth.

Simple Summary Glioblastoma multiforme is a common and lethal malignant brain tumor, and occurrence of therapeutic resistance in GBM often causes relapse. Therefore, this study aimed to find a new therapeutic strategy to treat these malignant tumors. In the current study, combined abemaciclib with an autophagy inhibitor, MPT0L145, significantly reduced cell proliferation and elevated intracellular reactive oxygen species (ROS) level. A blood–brain barrier permeability assay also showed that MPT0L145 could penetrate endothelial cells and has a penetration ability similar to that of TMZ. Therefore, this work represents a potential therapeutic strategy for treating the GBM in the future. Abstract Glioblastoma multiforme (GBM) is the most malignant brain tumor in the world, only 25% of GBM patients were alive one year after diagnosis. Although Temozolamide combined with radiation therapy more effectively prolonged the survival rate than radiation alone, the overall survival rate is still dismal. Therefore, a new therapeutic strategy is urgently needed. CDK4/6 inhibitors are newly FDA-approved agents to treat HR-positive, HER2-negative advanced, and metastatic breast cancers, and preclinical results showed that CDK4/6 inhibitors significantly reduced cell proliferation and tumor growth. However, several studies have suggested that CDK4/6 inhibitor-induced non-genetic changes caused treatment failure, including autophagy activation. Therefore, this study aimed to combine an autophagy inhibitor, MPT0L145, with abemaciclib to improve therapeutic efficiency. The use of abemaciclib effectively inhibited cell proliferation via suppression of RB phosphorylation and induced autophagy activation in GBM cancer cells. MPT0L145 treatment alone not only blocked autophagy activation, but also induced generation of ROS and DNA damage in a concentration-dependent manner. Importantly, MPT0L145 had a comparable penetration ability to TMZ in our blood brain barrier permeability assay. Combined MPT0L145 with abemaciclib significantly reduced cell proliferation, suppressed RB phosphorylation, and increased ROS production. In conclusion, the data suggested that blocking autophagy by MPT0L145 synergistically sensitized GBM cancer cells to abemaciclib and represents a potential therapeutic strategy for treating GBM in the future.