PKM2 aggregation drives metabolism reprograming during aging process.

While protein aggregation's association with aging and age-related diseases is well-established, the specific proteins involved and whether dissolving them could alleviate aging remain unclear. Our research addresses this gap by uncovering the role of PKM2 aggregates in aging. We find that PKM2 forms aggregates in senescent cells and organs from aged mice, impairing its enzymatic activity and glycolytic flux, thereby driving cells into senescence. Through a rigorous two-step small molecule library screening, we identify two compounds, K35 and its analog K27, capable of dissolving PKM2 aggregates and alleviating senescence. Further experiments show that treatment with K35 and K27 not only alleviate aging-associated signatures but also extend the lifespan of naturally and prematurely aged mice. These findings provide compelling evidence for the involvement of PKM2 aggregates in inducing cellular senescence and aging phenotypes, and suggest that targeting these aggregates could be a promising strategy for anti-aging drug discovery.

Discovery of 2,4-diarylaminopyrimidine derivatives bearing sulfonamide moiety as novel FAK inhibitors.

Two series of 2,4-diarylaminopyrimidine derivatives containing sulfonamide moiety were designed and synthesized for screening as inhibitors of focal adhesion kinase (FAK). Most compounds significantly inhibited the enzymatic activities of FAK, and the best compound was 7b (IC50 = 0.27 nM). A majority of aminoethyl sulfonamide derivatives could effectively inhibit the proliferation of human cancer cell lines (HCT116, A549, MDA-MB-231 and Hela) expressing high levels of FAK. Particularly, compounds 7b, 7c, and 7o exhibited more significant efficacy against all of four cancer cell lines within concentrations of 1.5 µM. Furthermore, these three compounds displayed higher selectivity of cancer cells over normal cells (SI value > 14), compared to the positive control TAE226 (SI value = 1.63). Interestingly, introduction of dithiocarbamate moiety to the aminoethyl sulfonamide derivatives can indeed improve the antiproliferative activities against A549 cells. Especially, compound 8d demonstrated most significant cytotoxicity activity against A549 cells with an IC50 value of 0.08 µM, which is 20-fold superior to parent compound 7k. Additionally, compound 7b, which display the best anti-FAK potency, can inhibit the clone formation and migration of HCT-116 cells, and cause cell cycle arrest at G2/M phase, inducing apoptosis by promoting ROS production. Overall, these results suggest that 7b is a valuable FAK inhibitor that deserves further optimization to improve its druggability.

Cerebrotendinous xanthomatosis presenting with schizophrenia-like disorder: A case report.

BACKGROUND: Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive lipid-storage disorder caused by mutations in CYP27A1. Psychiatric manifestations in CTX are rare and nonspecific, and they often lead to considerable diagnostic and treatment delay. CASE SUMMARY: A 33-year-old female patient admitted to the psychiatric ward for presentation of delusions, hallucinations, and behavioral disturbance is reported. The patient presented with cholestasis, cataract, Achilles tendon xanthoma, and cerebellar signs in adulthood and with intellectual disability and learning difficulties in childhood. After the characteristic CTX findings on imaging were obtained, a pathological examination of the Achilles tendon xanthoma was refined. Re-placement therapy was then initiated after the diagnosis was clarified by genetic analysis. During hospitalization in the psychiatric ward, the nonspecific psychiatric manifestations of the patient posed difficulty in diagnosis. After the patient's history of CTX was identified, the patient was diagnosed with organic schizophrenia-like disorder, and psychotic symptoms were controlled by replacement therapy combined with antipsychotic medication. CONCLUSION: Psychiatrists should be aware of CTX, its psychiatric manifestations, and clinical features and avoid misdiagnosis of CTX for timely intervention.

Discovery of a miniaturized PROTAC with potent activity and high selectivity.

The approved small-molecule inhibitors of anaplastic lymphoma kinase (ALK) have shown remarkable efficacy in some subset of cancer patients. However, the numerous ALK mutants or fusion partners are resistant to such drugs, greatly limiting their application in clinic. Despite the drug design strategy of proteolysis-targeting chimera (PROTAC) holds great potential to overcome drug resistance in theory, there are obvious disadvantages for the reported PROTACs that include high molecular weight, long linkers, difficult synthesis routes as well as insufficient evidence in activity for diverse ALK mutants. In this study, we designed and synthesized a miniaturized PROTAC of ALK named AP-1 following the principle of minimalist design. Two simple chemical units of ligands and a minimized linker with only two atoms were selected for synthesis of AP-1. At cellular level, AP-1 successfully degraded three types of ALK mutants including NPM-ALK, EML4-ALK and F1174L mutation ALK form with potent activity, high selectivity in ALK-positive cells. In xenograft mouse model, AP-1 showed the stronger antitumor efficacy than ceritinib as well as ALK degraders reported in literatures. AP-1 with an extremely simple PROTAC structure can be served as an effective candidate drug for therapy of various types of ALK-positive cancers. And the design principle of AP-1 has a good guiding significance for overcoming the disadvantages such as excessive molecular weight and poor solubility of PROTAC.

Identification of a new small molecule that initiates ferroptosis in cancer cells by inhibiting the system Xc- to deplete GSH.

Ferroptosis is a non-apoptotic cell death characterized by iron-mediated ROS accumulation and increasing lipid peroxidation. The activation of ferroptosis results in the destruction of cancer cells and overcoming the drug resistance associated with existing chemotherapeutic agents. It is essential to develop new ferroptosis inducers to provide new opportunities for cancer therapy. In this study, we found a small molecule Compound 8 which we had demonstrated to inhibit tumor growth in vivo initiated ferroptosis. Compound 8 treatment elevated the ferroptosis-related genes PTGS2 and CHAC1 mRNA levels in tumor cells. Ferroptosis inhibitors but not the necroptosis inhibitor or the apoptosis inhibitor can suppress the cell death induced by Compound 8. Compound 8 causes overall greater quantity of lipid peroxidation than the classic ferroptosis inducer Erastin through Flow cytometry analysis. The non-targeted lipidomic analysis also showed Compound 8 treatment resulted in oxidized lipid metabolites, similar to Erastin. The mechanism research showed that Compound 8 initiated ferroptosis by inhibiting the system Xc- to deplete GSH. Based on our previous study that Compound 8 blocked the interaction of PKM2 and VDAC3 (a regulator of ferroptosis) to inhibit tumor growth in vivo, Compound 8 may also trigger ferroptosis by regulating VADC3. Thus, Compound 8 not only will offer a potential tumor therapeutic alternative, but also provide an entrance to explore the new mechanism of ferroptosis.

Deubiquitinase OTUD3 regulates metabolism homeostasis in response to nutritional stresses.

The ovarian-tumor-domain-containing deubiquitinases (OTUDs) block ubiquitin-dependent protein degradation and are involved in diverse signaling pathways. We discovered a rare OTUD3 c.863G>A mutation in a family with an early age of onset of diabetes. This mutation reduces the stability and catalytic activity of OTUD3. We next constructed an experiment with Otud3-/- mice and found that they developed worse obesity, dyslipidemia, and insulin resistance than wild-type mice when challenged with a high-fat diet (HFD). We further found that glucose and fatty acids stimulate CREB-binding-protein-dependent OTUD3 acetylation, promoting its nuclear translocation, where OTUD3 regulates various genes involved in glucose and lipid metabolism and oxidative phosphorylation by stabilizing peroxisome-proliferator-activated receptor delta (PPARδ). Moreover, targeting PPARδ using a specific agonist can partially rescue the phenotype of HFD-fed Otud3-/- mice. We propose that OTUD3 is an important regulator of energy metabolism and that the OTUD3 c.863G>A is associated with obesity and a higher risk of diabetes.

Discovery of novel PRMT5 inhibitors bearing a methylpiperazinyl moiety.

Background: PRMT5 is an epigenetics-related enzyme, which plays a critical role in cancer development. Hence PRMT5 inhibition has been validated as a promising therapeutic strategy. Methods & Results: We synthesized a series of methylpiperazinyl derivatives as novel PRMT5 inhibitors that were achieved by scaffold-hopping from EPZ015666 by virtual screening followed by rational drug design. Among all compounds 43g, bearing a thiourea linker, showed antitumor activity across multiple cancer cell lines and reduced the level of symmetric arginine dimethylation of SmD3 dose-dependently. Moreover, 43g selectively inhibited PRMT5 among protein arginine methyltransferase isoforms. Further proteomics analysis revealed that 43g remarkably reduced the global arginine dimethylation level in a cellular context. Conclusion: This work provides new chemical templates for future structural optimization of PRMT5-related cancer treatments.

PPP2R1B is modulated by ubiquitination and is essential for spermatogenesis.

The serine-threonine protein phosphatase 2A (PP2A) is a heterotrimeric enzyme complex that regulates many fundamental cellular processes. PP2A is involved in tumorigenesis because mutations in the scaffold subunit, PPP2R1B, were found in several types of cancers. However, the biological function of PPP2R1B remains largely unknown. We report here that homozygous deletion of Ppp2r1b in Mus musculus impairs meiotic recombination and causes meiotic arrest in spermatocytes. Consistently, male mice lacking Ppp2r1b are characterized with infertility. Furthermore, heterozygous missense mutations in the Homo sapiens PPP2R1B gene, which encodes PPP2R1B, are identified in azoospermia patients with meiotic arrest. We found that PPP2R1B mutants are susceptible to degradation by an E3 ligase CRL4ADCAF6 , and resistant to de-polyubiquitylation by ubiquitin-specific protease 5 (USP5). In addition, heterozygous mutations in PPP2R1B reduce stability of the wild-type PPP2R1B. Our results demonstrate an essential role of PPP2R1B in spermatogenesis and identify upstream regulators of PPP2R1B.

Synthesis of novel sulfonamide derivatives containing pyridin-3-ylmethyl 4-(benzoyl)piperazine-1-carbodithioate moiety as potent PKM2 activators.

Pyruvate kinase M2 isoform (PKM2) plays a key role in cancer progression through both metabolic and non-metabolic functions, thus it is recognized as a potential target for cancer diagnosis and treatment. In this study, we discovered a sulfonamide-dithiocarbamate compound 8a as a novel PKM2 activator from a random screening of an in-house compound library. Then, a series of lead compound 8a analogs were designed and synthesized for screening as potent PKM2 activators. Among them, compound 8b (AC50 = 0.136 µM) and 8k (AC50 = 0.056 µM) showed higher PKM2 activation activities than positive control NZT (AC50 = 0.228 µM), and they (IC50 < 1 µM) exhibited more significant anti-proliferative activities against human tumor cell lines than NZT (IC50 > 10 µM). Especially, compound 8k inhibited the proliferation of multiple cancer cells, but showed little toxicity on normal cells. In addition, we found that compound 8k inhibit the colony formation of MCF7 cells. Western blot analysis demonstrated that 8k could reduce PKM2 nuclear localization and block the downstream signaling pathway of PKM2, resulting in suppression of tumor cell proliferation. Overall, compound 8k may be a promising candidate for further mechanistic investigation of PKM2 and cancer therapy.

Design, Synthesis, and Resolution of Spirocyclic Bisoxindole-Based C2-Symmetric Diols.

A new type of spirocyclic bisoxindole-based C2-symmetric diols (SBIDOLs) was designed and synthesized. A series of racemic SBIDOL derivatives (6a-6g) were readily synthesized from commercially available 2-halo-5-methoxyanilines 1 (X = Cl or Br) through N-mono alkylation, acylation, oxidation, double intramolecular Friedel-Crafts reaction, and demethylation reactions. The optical resolution of racemic 6b was achieved via fractional crystallization of their bis-l-menthoxycarboxylates. Further modifications of SBIDOLs were investigated, leading to 5,5'-diaryl SBIDOL derivatives (11a and 11b) through Pd-catalyzed Suzuki coupling and DM-SBIDOL 12 by Pd/C-catalyzed hydrogenative dechlorination reactions.

Ruthenium-Catalyzed Highly Enantioselective Synthesis of cis-3-Quinuclidinols via DKR Asymmetric Transfer Hydrogenation.

A method for the enantioselective synthesis of cis-3-quinuclidinols by Ru-catalyzed asymmetric transfer hydrogenation via dynamic kinetic resolution is described. The reaction proceeded under mild conditions using ammonium formate as the hydrogen donor, affording the products in high yields (up to 99%) with excellent diastereoselectivity (up to 99:1 dr) and enantioselectivity (95-99% ee). This protocol was applicable to gram-scale preparation with perfect enantioselectivity through simple recrystallization.

Erythrocyte-mimicking paclitaxel nanoparticles for improving biodistributions of hydrophobic drugs to enhance antitumor efficacy.

Recent decades have witnessed several nanocrystal-based hydrophobic drug formulations because of their excellent performance in improving drug loading and controlling drug release as mediate drug forms in tablets or capsules. However, the intravenous administration of drug nanocrystals was usually hampered by their hydrophobic surface properties, causing short half-life time in circulation and low drug distribution in tumor. Here, we proposed to enclose nanocrystals (NC) of hydrophobic drug, such as paclitaxel (PTX) into erythrocyte membrane (EM). By a series of formulation optimizations, spherical PTX nanoparticles (PN) with the particle size of around 280 nm were successfully cloaked in erythrocyte membrane, resulting in a PTX-NP-EM (PNM) system. The PNM could achieve high drug loading of PTX (>60%) and stabilize the particle size significantly compared to PN alone. Besides, the fluorescence-labeling PNM presented better tumor cell uptake, stronger cytotoxicity, and higher drug accumulation in tumor compared to PN. Finally, the PNM was found to be the most effective against tumor growth among all PTX formulations in tumor-bearing mice models, with much lower system toxicity than control formulation. In general, the PNM system with high drug-loading as well as superior bio-distributions in vivo could be served as a promising formulation.

Design, synthesis and biological evaluation of novel dithiocarbamate-substituted diphenylaminopyrimidine derivatives as BTK inhibitors.

Bruton's tyrosine kinase (BTK) has emerged as an attractive target related to B-lymphocytes dysfunctions, especially hematologic malignancies and autoimmune diseases. In our study, a series of diphenylaminopyrimidine derivatives bearing dithiocarbamate moieties were designed and synthesized as novel BTK inhibitors for treatment of B-cell lymphoma. Among all these compounds, 30ab (IC50 = 1.15 ±â€¯0.19 nM) displays similar or more potent inhibitory activity against BTK than spebrutinib (IC50 = 2.12 ±â€¯0.32 nM) and FDA approved drug ibrutinib (IC50 = 3.89 ±â€¯0.57 nM), which is attributed to close binding of 30ab with BTK predicted by molecular docking. In particular, 30ab exhibits enhanced anti-proliferative activity against B-lymphoma cell lines at the IC50 concentration of 0.357 ±â€¯0.02 µM (Ramos) and 0.706 ±â€¯0.05 µM (Raji), respectively, almost 10-fold better than ibrutinib and spebrutinib. In addition, 30ab displays stronger selectivity on B-cell lymphoma over other cancer cell lines than spebrutinib. Furthermore, 30ab efficiently blocks BTK downstream pathways and results in apoptosis of cancer cells. In vivo xenograft model evaluation demonstrates the significant efficacy and broad safety margin of 30ab in treatment of B-cell lymphoma. We propose that compound 30ab is a candidate for further study and development based on our current findings.

Glutathione-Priming Nanoreactors Enable Fluorophore Core/Shell Transition for Precision Cancer Imaging.

In an attempt to develop an imaging probe with ultra-high sensitivity for a broad range of tumors in vivo and inspired by the concept of chemical synthetic nanoreactors, we designed a type of glutathione-priming fluorescent nanoreactor (GPN) with an albumin-coating shell and hydrophobic polymer core containing disulfide bonds, protonatable blocks, and indocyanine green (ICG), a near-infrared fluorophore. The albumin played multiple roles including biocompatible carriers, hydrophilic stabilizer, "receptor" of the fluorophores, and even targeting molecules. The protonation of the hydrophobic core triggered the outside-to-core transport of acidic glutathione (GSH), as well as the core-to-shell transference of ICGs after the disulfide bond cleavage by GSH, which induced strong binding of fluorophores with albumins on the GPN shell, initiating intensive fluorescence signals. As a result, the GPNs demonstrated extremely high response sensitivity and imaging contrast, proper time window, and broad cancer specificity. In fact, an orthogonal activation pattern was found in vitro with an ON/OFF ratio up to 24.7-fold. Furthermore, the nanoprobes specifically amplified the tumor signals in five cancer-bearing mouse models and actualized tumor margin delineation with a contrast up to 20-fold, demonstrating much better imaging efficacy than the other four commercially available probes. Therefore, the GPNs provide a new paradigm in developing high-performance bioresponsive nanoprobes.

Synthesis and anti-tumor efficacy of novel 2, 4-diarylaminopyrimidine derivatives bearing N-(3-pyridinylmethyl) urea moiety as anaplastic lymphoma kinase inhibitors.

Anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase responsible for development of various tumor types. In this study, we synthesized a series of novel 2,4-diarylaminopyrimidine derivatives possessing a unique N-(3-pyridinylmethyl)urea moiety as ALK inhibitors. The most promising analog 5m bearing a 3-methoxy-4-morpholinophenyl substituent significantly inhibited proliferation of ALK positive H3122 and Karpas-299 cells with IC50 values about 10 nM, which were comparable with positive control LDK378. Compound 5m suppressed phosphorylation of ALK and its downstream proteins, and showed low cytotoxicity on normal human primary fibroblast cells (BJ cells). The binding mode of 5m was proposed by docking simulation, which explains the important role of N-(3-pyridinylmethyl)urea moiety. Furthermore, compound 5m exhibited favorable liver microsomal stability and significant efficacy in H3122 xenograft mice model. Interestingly, compound 5m also showed broader anti-proliferative activity on other human tumor cell lines, which was different from other ALK inhibitors.

Discovery of 2,4-diarylaminopyrimidine derivatives bearing dithiocarbamate moiety as novel FAK inhibitors with antitumor and anti-angiogenesis activities.

A series of 2,4-diarylaminopyrimidine derivatives containing dithiocarbamate moiety were designed by molecular hybridization strategy and synthesized for screening as inhibitors of focal adhesion kinase (FAK). Most of these compounds exhibit significant antiproliferative activities on human cancer cell lines expressing high levels of FAK at nanomolar concentrations. The compound 14z was identified as the most potent FAK inhibitor among these candidates. 14z has excellent anti-proliferative effect with IC50 values from 0.001 µM to 0.06 µM on HCT116, PC-3, U87-MG and MCF-7 cell lines and relatively less cytotoxicity to a nonmalignant cell line MCF-10A compared with MCF-7 cells (SI value > 10). 14z also exhibits significant FAK inhibitory activity (IC50 = 0.07 nM). In addition, compound 14z causes cell cycle arrest at G2/M and prompted apoptosis in both HCT116 and MCF-7 cells in a dose-dependent manner. Further studies show that compound 14z inhibits migration of MCF-7 and has anti-angiogenesis effect on HUVEC cells.

Synthesis of novel 7-azaindole derivatives containing pyridin-3-ylmethyl dithiocarbamate moiety as potent PKM2 activators and PKM2 nucleus translocation inhibitors.

Multiple lines of evidence have indicated that pyruvate kinase M2 (PKM2) is upregulated in most cancer cells and it is increasingly recognized as a potential therapeutic target in oncology. In a continuation of our discovery of lead compound 5 and SAR study, the 7-azaindole moiety in compound 5 was systematically optimized. The results showed that compound 6f, which has a difluoroethyl substitution on the 7-azaindole ring, exhibited high PKM2 activation potency and anti-proliferation activities on A375 cell lines. In a xenograft mouse model, oral administration of compound 6f led to significant tumor regression without obvious toxicity. Further mechanistic studies revealed that 6f could influence the translocation of PKM2 into nucleus, as well as induction of apoptosis and autophagy of A375 cells. More importantly, compound 6f significantly inhibited migration of A375 cells in a concentration-dependent manner. Collectively, 6f may serve as a lead compound in the development of potent PKM2 activators for cancer therapy.

Anti-cancer effect of a novel 2,3-didithiocarbamate-substituted naphthoquinone as a tumor metabolic suppressor in vitro and in vivo.

Tumor cells reprogram their cellular metabolism by switching from oxidative phosphorylation to aerobic glycolysis to support aberrant cell proliferation. Suppressing tumor cell metabolism has become an attractive strategy for treating cancer patients. In this study, we identified a 2,3-didithiocarbamate-substituted naphthoquinone 3i that inhibited the proliferation of tumor cells by disturbing their metabolism. Compound 3i reduced cancer cell viability with IC50 values from 50 nM to 150 nM against HCT116, MCF7, MDA-MB231, HeLa, H1299 and B16 cells. Further, compound 3i was found to suppress ATP production in cultured cancer cells, inhibit the M2 isoform of pyruvate kinase (PKM2) which is a rate-limiting enzyme in the glycolytic pathway and block the subsequent transcription of the downstream genes GLUT1, LDH and CCND1. In addition, exposure to compound 3i significantly suppressed tumor growth in a B16 melanoma transplantation mouse model and a spontaneous breast carcinoma mouse model in vivo. The identification of compound 3i as a tumor metabolic suppressor not only offers a candidate compound for cancer therapy, but also provides a tool for an in-depth study of tumor metabolism.

Discovery and optimization of 2-thio-5-amino substituted benzoquinones as potent anticancer agents.

Based on our discovered novel lead compound 1 through phenotypic drug discovery (PDD) approaches, systematic structural optimization was performed. A series of 2-allylthio-5-amino substituted benzoquinones were synthesized and evaluated for their in-vitro anticancer activities against human prostate cancer cell line PC3. The compound 7a was found inhibit the growth of PC3 with an IC50 of 0.22 µM, which is over 20-fold improvement compared to lead compound 1. It is noteworthy that compound 7a also showed potent anti-proliferation activity toward a panel of cancer cells with relatively less cytotoxicity to nonmalignant cell, as well as good water solubility.

Synthesis and antitumor activity of novel 2, 3-didithiocarbamate substituted naphthoquinones as inhibitors of pyruvate kinase M2 isoform.

The M2 isoform of pyruvate kinase (PKM2) is a potential antitumor therapeutic target. In this study, we designed and synthesised a series of 2, 3-didithiocarbamate substituted naphthoquinones as PKM2 inhibitors based on the lead compound 3k that we previously reported. Among them, compound 3f (IC50 = 1.05 ± 0.17 µM) and 3h (IC50 = 0.96 ± 0.18 µM) exhibited potent inhibition of PKM2, and their inhibitory activities are superior to compound 3k (IC50 = 2.95 ± 0.53 µM) and the known PKM2 inhibitor shikonin (IC50 = 8.82 ± 2.62 µM). In addition, we evaluated in vitro antiproliferative effects of target compounds using MTS assay. Most target compounds exhibited dose-dependent cytotoxicity with IC50 values in nanomolar concentrations against HCT116, MCF7, Hela, H1299 and B16 cells. These small molecule PKM2 inhibitors not only provide candidate compounds for cancer therapy, but also offer a tool to probe the biological effects of PKM2 inhibition on cancer cells.