Glycogen Synthase Kinase 3β in Cancer Biology and Treatment

e-QSAR (Explainable AI-QSAR), molecular docking, and ADMET analysis of structurally diverse GSK3-beta modulators to identify concealed modulatory features vindicated by X-ray

Glycogen Synthase Kinase-3 beta (GSK-3β) is a crucial enzyme linked to various cellular processes, including neurodegeneration, autophagy, and diabetes. A structurally diverse set of 1293 molecules having GSK-3β modulatory activity has been used. Molecular docking and eXplainable Artificial Intelligence (XAI) have been used concomitantly. The approach involves using GA for feature selection and XGBoost for in-depth analysis, yielding strong statistical validation with R2tr = 0.9075, R2L10 %O = 0.9116, and Q2F3 = 0.7841. Molecular docking provided complementary and similar results. Machine learning model interpretation using SHapley Additive exPlanations (SHAP) revealed that specific structural features like aromatic carbon with specific partial charges, non-ring nitrogen atoms, sp3-hybrid carbon atoms, and the topological distance between carbon and nitrogen atoms, among others, significantly influence the modulatory profile. The results are also supported by reported X-ray resolved structures. In addition, in-silico ADMET analysis is also accomplished. This research underscores the value of advanced machine learning techniques in understanding complex biological phenomena and supporting rational drug design.

A highly efficient, scalable pipeline for fixed feature extraction from large-scale high-content imaging screens

Applying artificial intelligence (AI) to image-based morphological profiling cells offers significant potential for identifying disease states and drug responses in high-content imaging (HCI) screens. When differences between populations (e.g., healthy vs. diseased) are unknown or imperceptible to the human eye, large-scale HCI screens are essential, providing numerous replicates to build reliable models and accounting for confounding factors like donor and intra-experimental variations. As screen sizes grow, so does the challenge of analyzing high-dimensional datasets in an efficient way while preserving interpretable features and predictive power. Here, we introduce ScaleFEx℠, a memory-efficient, open-source Python pipeline that extracts biologically meaningful features from HCI datasets using minimal computational resources or scalable cloud infrastructure. ScaleFEx can be used together with AI models to successfully identify phenotypic shifts in drug-treated cells and rank interpretable features, and is applicable to public datasets, highlighting its potential to accelerate the discovery of disease-associated phenotypes and new therapeutics.

Campylobacter jejuni-derived cytolethal distending toxin promotes colorectal cancer metastasis

Various forms of solid tumors harbor intracellular bacteria, but the physiological consequences of these microorganisms are poorly understood. We show that Campylobacter is significantly enriched in primary colorectal cancer (CRC) lesions from patients with metastasis. Campylobacter jejuni-derived cytolethal distending toxin (CDT) promotes CRC metastasis through JAK2-STAT3-MMP9 signaling in liver or pulmonary metastatic mice models, as confirmed in C. jejuni-infected human colonic tissue and CDT-treated colonic tumoroids from patients. Genetic deletion of cdtB (ΔcdtB) or purified CdtB protein demonstrates that the genotoxin is essential for C. jejuni's pro-metastatic property. In C.-jejuni-colonized mice, increased translocation of CDT-producing C. jejuni to extraintestinal implanted tumors potentially leads to accelerated metastasis of these tumors. Overall, these findings demonstrate that an intratumor-bacteria-derived genotoxin accelerates tumor metastasis, potentially opening a new diagnostic and therapeutic avenue for cancer management.

Lithium Enhances Ferroptosis sensitivity in melanoma cells and promotes CD8+ T Cell infiltration and differentiation

Lithium exposure reduces melanoma incidence and mortality, yet its therapeutic mechanisms are unclear. This study explores the effects of lithium on ferroptosis sensitivity and anti-tumor T cell response in melanoma. We found that lithium significantly enhanced RSL3-induced ferroptosis in vitro, evidenced by increased mitochondrial peroxide, lipid peroxidation, and mitochondrial abnormalities. Lithium also inhibited B16-F10 melanoma cell proliferation and migration in a dose-dependent manner. Cell cycle analysis showed lithium and RSL3 induced distinct perturbations, including G2/M and G0/G1 phase arrests. Mechanistically, lithium influenced intracellular ferrous ion levels by downregulating ferritin heavy chain (Fth1), crucial for iron homeostasis. The combination of lithium and RSL3 significantly suppressed tumor growth in mice, correlating with reduced Fth1 expression and increased iron deposition in the spleen and liver, highlighting a novel interaction between lithium and iron metabolism. Additionally, this combination enhanced CD8+ T cell infiltration and IFN-γ expression in the tumor microenvironment, especially among cytotoxic effector CD8+ T cells. These findings reveal the pro-ferroptotic and immune regulation roles of lithium, broaden our understanding of its biological roles, and propose new strategies for ferroptosis-targeted therapies in melanoma.

A New Strategy for Adult T-Cell Leukemia Treatment Targeting Glycogen Synthase Kinase-3β

OBJECTIVES

The role of glycogen synthase kinase (GSK)-3β in adult T-cell leukemia (ATL) caused by human T-cell leukemia virus type 1 (HTLV-1) is paradoxical and enigmatic. Here, we investigated the role of GSK-3β and its potential as a therapeutic target for ATL.

METHODS

Cell proliferation/survival, cell cycle, apoptosis, and reactive oxygen species (ROS) generation were examined using the WST-8 assay, flow cytometry, and Hoechst 33342 staining, respectively. Expression of GSK-3β and cell cycle/death-related proteins, and survival signals was analyzed using RT-PCR, immunofluorescence staining, and immunoblotting.

RESULTS

HTLV-1-infected T-cell lines showed nuclear accumulation of GSK-3β. GSK-3β knockdown and its inhibition with 9-ING-41 and LY2090314 suppressed cell proliferation/survival. 9-ING-41 induced G2/M arrest by enhancing the expression of γH2AX, p53, p21, and p27, and suppressing the expression of CDK1, cyclin A/B, and c-Myc. It induced caspase-mediated apoptosis by decreasing the expression of Bcl-xL, Mcl-1, XIAP, c-IAP1/2, and survivin, and increasing the expression of Bak and Bax. 9-ING-41 also induced ferroptosis and necroptosis, promoted JNK phosphorylation, and suppressed IKKγ and JunB expression. It inhibited the phosphorylation of IκBα, Akt, and STAT3/5, induced ROS production, and reduced glycolysis-derived lactate levels.

CONCLUSION

GSK-3β functions as an oncogene in ATL and could be a potential therapeutic target.

Design, Synthesis, Biological Evaluation and Molecular Docking Studies of a New Series of Maleimide Derivatives

A series of novel maleimide derivatives were synthesized, with various heterocyclic compounds serving as side chains in the synthesis process. The structural characteristics of these compounds were elucidated through the application of 1H-NMR spectroscopy, 13C-NMR (APT) spectroscopy, and high-resolution mass spectrometry (HRMS). The anti-cancer potential of these compounds was subsequently assessed in vitro, utilizing two distinct breast cancer cell lines, namely MDA-MB-231 and MCF-7, via MTT assay. Among the 12 newly synthesized compounds, 4 a, 4 b, 4 c, 4 d, 5 a, 5 b, 5 c and 5 d were determined to show the most promising anti-cancer activity against both breast cancer cell lines. Moreover, the morphological changes induced in the cells following a 24-hour incubation period with these compounds were observed using light microscopy. Additionally, molecular dynamics simulations were conducted to assess the stability of the bound conformations of the compounds to the target protein GSK-3β as obtained through molecular docking calculations.

Fructose 1,6-bisphosphatase as a promising target of anticancer treatment

Fructose 1,6-bisphosphatase (FBP) is a regulatory enzyme of gluconeogenesis that also influences in a non-catalytic manner - via protein-protein interactions - cell cycle-dependent events, mitochondria biogenesis and polarization, synaptic plasticity and even cancer progression. FBP reduces glycolytic capacity of cells via blocking HIF-1α transcriptional activity and modulating NF-κB action, and influences oxidative metabolism by binding to c-MYC. Because FBP limits the energy-producing potential of cells and because a reduction of FBP amounts is observed in cancer cells, FBP is considered to be an anti-oncogenic protein. This is supported by the observation that cancer cells overexpress aldolase A (ALDOA), a pro-oncogenic protein that can bind to FBP and potentially block its anti-oncogenic activity. Interestingly, only the muscle isozyme of FBP (FBP2) interacts strongly with ALDOA, whereas the binding of the liver isozyme (FBP1) to ALDOA is more than an order of magnitude weaker. Here, we briefly review the most important evidence supporting the anti-oncogenic function of FBP and discuss what structural properties of the two FBP isozymes allow FBP2, rather than FBP1, to exert more flexible anticancer functions.

A spotlight on the role of copper in the epithelial to mesenchymal transition

The complex process known as epithelial to mesenchymal transition (EMT) plays a fundamental role in several biological settings, encompassing embryonic development, wound healing, and pathological conditions such as cancer and fibrosis. In recent years, a bulk of research has brought to light the key role of copper, a trace element with essential functions in cellular metabolism, cancer initiation and progression. Indeed, copper, besides functioning as cofactor of enzymes required for essential cellular processes, such as energy production and oxidation reactions, has emerged as an allosteric regulator of kinases whose activity is required to fulfill cancer dissemination through the EMT. In this comprehensive review, we try to describe the intricate relationship between the transition metal copper and EMT, spanning from the earliest foundational studies to the latest advancements. Our aim is to shed light on the multifaceted roles undertaken by copper in EMT in cancer and to unveil the diverse mechanisms by which copper homeostasis exerts its influence over EMT regulators, signaling pathways, cell metabolic reprogramming and transcription factors ultimately contributing to the spread of cancer. Therefore, this review not only may contribute to a deeper comprehension of copper-mediated mechanisms in EMT but also supports the hypothesis that targeting copper may contribute to counteract the progression of EMT-associated pathologies.

Design, synthesis and in vitro anti-proliferative evaluation of new pyridine-2,3-dihydrothiazole/thiazolidin-4-one hybrids as dual CDK2/GSK3β kinase inhibitors

Herein, the molecular hybridization drug discovery approach was used in the design and synthesis of twelve novel pyridine-2,3-dihydrothiazole hybrids (2a,b-5a,b and 13a,b-14a,b) and fourteen pyridine-thiazolidin-4-one hybrids (6a,b-12a,b) as anti-proliferative analogues targeting CDK2 and GSK3β kinase inhibition. Almost all of the newly synthesized hybrids, including their precursors (1a,b), were evaluated for their anti-proliferative activity against three human cancer cell lines-MCF-7, HepG2 and HEp-2-as well as normal Vero cell lines. Both compounds 1a (pyridine-thiourea precursor) and 8a (pyridine-5-acetyl-thiazolidin-4-one hybrid) exhibited excellent anti-proliferative activity against HEp-2 (IC50 = 7.5 μg mL-1, 5.9 μg mL-1, respectively). Additionally, 13a (pyridine-5-(p-tolyldiazenyl-2,3-dihydrothiazole)) hybrid demonstrated excellent anti-proliferative activity against HepG2 (IC50 = 9.5 μg mL-1), with an acceptable safety profile against Vero (<45% inhibition at 100 μg mL-1) in the cases of 8a and 13a alone. The three promising anti-proliferative hybrids (1a, 8a, 13a) were selected for the assessment of their in vitro inhibitory kinase activity against CDK2/GSK3β using roscovitine (IC50 = 0.88 μg mL-1) and CHIR-99021 (IC50 = 0.07 μg mL-1) as references, respectively. Compound 13a was the most potent dual CDK2/GSK3β inhibitor (IC50 = 0.396 μg mL-1, 0.118 μg mL-1, respectively) followed by 8a (IC50 = 0.675 μg mL-1, 0.134 μg mL-1, respectively), and the weakest was 1a. To elucidate the mechanism of the most potent anti-proliferative 13a hybrid, further cell cycle analysis was performed revealing that it caused G1 cell cycle arrest and induced apoptosis. Moreover, it resulted in an increase in Bax and caspase-3 with a decrease in Bcl-2 levels in HepG2 cells compared with untreated cells. Finally, in silico drug likeness/ADME prediction for the three potent compounds as well as a molecular docking simulation study were conducted in order to explore the binding affinity and interactions in the binding site of each enzyme, which inspired their usage as anti-proliferative leads for further modification.

γ-Tocotrienol enhances autophagy of gastric cancer cells by the regulation of GSK3β/β-Catenin pathway

γ-Tocotrienol (γ-T3) is a major subtype of vitamin E, mainly extracted from palm trees, barley, walnuts, and other plants. γ-T3 has effects on anti-inflammation, anti-oxidation, and potential chemoprevention against malignancies. It is still uncompleted to understand the effect of γ-T3 on the inhibitory mechanism of cancer. This study aimed to investigate whether γ-T3 enhanced autophagy in gastric cancer and the underlying molecular mechanism. The results showed that γ-T3 (0-90 μmol/L) inhibited the proliferation of gastric cancer MKN45 cells and AGS cells, and arrested the cell cycle at the G0/G1 phase in a dose-dependent manner. Autophagy was increased in MKN45 cells treated with γ-T3 (0-45 μmol/L), especially at a dose of 30 μmol/L for 24 h. These effects were reversed by 3-methyladenine pretreatment. Furthermore, γ-T3 (30 μmol/L) also significantly downregulated the expression of pGSK-3β (ser9) and β-catenin protein in MKN45 cells, and γ-T3 (20 mg/kg b.w.) effectively decreased the growth of MKN45 cell xenografts in BABL/c mice. GSK-3β inhibitor-CHIR-99021 reversed the negative regulation of GSK-3β/β-Catenin signaling and autophagy. Our findings indicated that γ-T3 enhances autophagy in gastric cancer cells mediated by GSK-3β/β-Catenin signaling, which provides new insights into the role of γ-T3 enhancing autophagy in gastric cancer.

Natural compound screening predicts novel GSK-3 isoform-specific inhibitors

Glycogen synthase kinase-3 (GSK-3) plays important roles in the pathogenesis of cardiovascular, metabolic, neurological disorders and cancer. Isoform-specific loss of either GSK-3α or GSK-3β often provides cytoprotective effects under such clinical conditions. However, available synthetic small molecule inhibitors are relatively non-specific, and their chronic use may lead to adverse effects. Therefore, screening for natural compound inhibitors to identify the isoform-specific inhibitors may provide improved clinical utility. Here, we screened 70 natural compounds to identify novel natural GSK-3 inhibitors employing comprehensive in silico and biochemical approaches. Molecular docking and pharmacokinetics analysis identified two natural compounds Psoralidin and Rosmarinic acid as potential GSK-3 inhibitors. Specifically, Psoralidin and Rosmarinic acid exhibited the highest binding affinities for GSK-3α and GSK-3β, respectively. Consistent with in silico findings, the kinase assay-driven IC50 revealed superior inhibitory effects of Psoralidin against GSK-3α (IC50 = 2.26 μM) vs. GSK-3β (IC50 = 4.23 μM) while Rosmarinic acid was found to be more potent against GSK-3β (IC50 = 2.24 μM) than GSK-3α (IC50 = 5.14 μM). Taken together, these studies show that the identified natural compounds may serve as GSK-3 inhibitors with Psoralidin serving as a better inhibitor for GSK-3α and Rosmarinic for GSK-3β isoform, respectively. Further characterization employing in vitro and preclinical models will be required to test the utility of these compounds as GSK-3 inhibitors for cardiometabolic and neurological disorders and cancers.

Multi-modal mechanisms of the metastasis suppressor, NDRG1: Inhibition of WNT/β-catenin signaling by stabilization of protein kinase Cα

The metastasis suppressor, N-myc downstream regulated gene-1 (NDRG1), inhibits pro-oncogenic signaling in pancreatic cancer (PC). This investigation dissected a novel mechanism induced by NDRG1 on WNT/β-catenin signaling in multiple PC cell types. NDRG1 overexpression decreased β-catenin and downregulated glycogen synthase kinase-3β (GSK-3β) protein levels and its activation. However, β-catenin phosphorylation at Ser33, Ser37, and Thr41 are classically induced by GSK-3β was significantly increased after NDRG1 overexpression, suggesting a GSK-3β-independent mechanism. Intriguingly, NDRG1 overexpression upregulated protein kinase Cα (PKCα), with PKCα silencing preventing β-catenin phosphorylation at Ser33, Ser37, and Thr41, and decreasing β-catenin expression. Further, NDRG1 and PKCα were demonstrated to associate, with PKCα stabilization occurring after NDRG1 overexpression. PKCα half-life increased from 1.5 ± 0.8 h (3) in control cells to 11.0 ± 2.5 h (3) after NDRG1 overexpression. Thus, NDRG1 overexpression leads to the association of NDRG1 with PKCα and PKCα stabilization, resulting in β-catenin phosphorylation at Ser33, Ser37, and Thr41. The association between PKCα, NDRG1, and β-catenin was identified, with the formation of a potential metabolon that promotes the latter β-catenin phosphorylation. This anti-oncogenic activity of NDRG1 was multi-modal, with the above mechanism accompanied by the downregulation of the nucleo-cytoplasmic shuttling protein, p21-activated kinase 4 (PAK4), which is involved in β-catenin nuclear translocation, inhibition of AKT phosphorylation (Ser473), and decreased β-catenin phosphorylation at Ser552 that suppresses its transcriptional activity. These mechanisms of NDRG1 activity are important to dissect to understand the marked anti-cancer efficacy of NDRG1-inducing thiosemicarbazones that upregulate PKCα and inhibit WNT signaling.

Beyond Psychotropic: Potential Repurposing of Fluoxetine toward Cancer Therapy

Drug repurposing, rebranding an existing drug for a new therapeutic indication, is deemed a beneficial approach for a quick and cost-effective drug discovery process by skipping preclinical, Phase 1 trials and pharmacokinetic studies. Several psychotropic drugs, including selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs), were studied for their potential application in different diseases, especially in cancer therapy. Fluoxetine (FLX) is one of the most prescribed psychotropic agents from the SSRIs class for the treatment of several neuropsychiatric disorders with a favorable safety profile. FLX exhibited different oncolytic effects via mechanisms distinct from its main serotonergic activity. Taking advantage of its ability to rapidly penetrate the blood-brain barrier, FLX could be particularly useful in brain tumors. This was proved by different in vitro and in vivo experiments using FLX as a monotherapy or combination with temozolomide (TMZ) or radiotherapy. In this review of the literature, we summarize the potential pleiotropic oncolytic roles of FLX against different cancers, highlighting the multifaceted activities of FLX and its ability to interrupt cancer proliferation via several molecular mechanisms and even surmount multidrug resistance (MDR). We elaborated on the successful synergistic combinations such as FXR/temozolomide and FXR/raloxifene for the treatment of glioblastoma and breast cancer, respectively. We showcased beneficial pharmaceutical trials to load FLX onto carriers to enhance its safety and efficacy on cancer cells. This is the first review article extensively summarizing all previous FLX repurposing studies for the management of cancer.

The scaffold protein disabled 2 (DAB2) and its role in tumor development and progression

BACKGROUND

Disabled 2 (DAB2) is a multifunctional protein that has emerged as a critical component in the regulation of tumor growth. Its dysregulation is implicated in various types of cancer, underscoring its importance in understanding the molecular mechanisms underlying tumor development and progression. This review aims to unravel the intricate molecular mechanisms by which DAB2 exerts its tumor-suppressive functions within cancer signaling pathways.

METHODS AND RESULTS

We conducted a comprehensive review of the literature focusing on the structure, expression, physiological functions, and tumor-suppressive roles of DAB2. We provide an overview of the structure, expression, and physiological functions of DAB2. Evidence supporting DAB2's role as a tumor suppressor is explored, highlighting its ability to inhibit cell proliferation, induce apoptosis, and modulate key signaling pathways involved in tumor suppression. The interaction between DAB2 and key oncogenes is examined, elucidating the interplay between DAB2 and oncogenic signaling pathways. We discuss the molecular mechanisms underlying DAB2-mediated tumor suppression, including its involvement in DNA damage response and repair, regulation of cell cycle progression and senescence, and modulation of epithelial-mesenchymal transition (EMT). The review explores the regulatory networks involving DAB2, covering post-translational modifications, interactions with other tumor suppressors, and integration within complex signaling networks. We also highlight the prognostic significance of DAB2 and its role in pre-clinical studies of tumor suppression.

CONCLUSION

This review provides a comprehensive understanding of the molecular mechanisms by which DAB2 exerts its tumor-suppressive functions. It emphasizes the significance of DAB2 in cancer signaling pathways and its potential as a target for future therapeutic interventions.

Capivasertib combines with docetaxel to enhance anti-tumour activity through inhibition of AKT-mediated survival mechanisms in prostate cancer

BACKGROUND/OBJECTIVE

To explore the anti-tumour activity of combining AKT inhibition and docetaxel in PTEN protein null and WT prostate tumours.

METHODS

Mechanisms associated with docetaxel capivasertib treatment activity in prostate cancer were examined using a panel of in vivo tumour models and cell lines.

RESULTS

Combining docetaxel and capivasertib had increased activity in PTEN null and WT prostate tumour models in vivo. In vitro short-term docetaxel treatment caused cell cycle arrest in the majority of cells. However, a sub-population of docetaxel-persister cells did not undergo G2/M arrest but upregulated phosphorylation of PI3K/AKT pathway effectors GSK3β, p70S6K, 4E-BP1, but to a lesser extent AKT. In vivo acute docetaxel treatment induced p70S6K and 4E-BP1 phosphorylation. Treating PTEN null and WT docetaxel-persister cells with capivasertib reduced PI3K/AKT pathway activation and cell cycle progression. In vitro and in vivo it reduced proliferation and increased apoptosis or DNA damage though effects were more marked in PTEN null cells. Docetaxel-persister cells were partly reliant on GSK3β as a GSK3β inhibitor AZD2858 reversed capivasertib-induced apoptosis and DNA damage.

CONCLUSION

Capivasertib can enhance anti-tumour effects of docetaxel by targeting residual docetaxel-persister cells, independent of PTEN status, to induce apoptosis and DNA damage in part through GSK3β.

Impact of Prospero Homeobox-1 (PROX-1) οn the Oncogenic Phenotypes of Hepatocellular Carcinoma Cells

BACKGROUND/AIM

Transcriptional factor prospero homeobox-1 (PROX-1) is crucial for the embryonic development of various organs and cell fate specification. It exhibits either an oncogenic or tumor suppressive activity depending on cancer types. However, the relationship between PROX-1 and hepatocellular carcinoma (HCC) remains obscure. This study was conducted to investigate the effect of PROX-1 on the invasive and oncogenic phenotypes of human HCC cells.

MATERIALS AND METHODS

The effect of PROX-1 on tumor cell behavior was investigated by using a pcDNA-myc vector and a small interfering RNA in HepG2 and Huh7 human HCC cell lines. Flow cytometry, migration, invasion, proliferation, and tube formation assays were performed. PROX-1 expression in human HCC cells was explored by western blotting.

RESULTS

PROX-1 overexpression enhanced tumor cell proliferation and inhibited apoptosis and cell cycle arrest by modulating the activities of caspase-3, PARP, and cyclin-dependent kinase inhibitors, including p21, p27, and p57 in HCC cells. After PROX-1 overexpression, the number of migrating and invading HCC cells significantly increased, and the expression levels of N-cadherin and Snail increased in HCC cells. PROX-1 overexpression enhanced angiogenesis through increased VEGF-A and VEGF-C expression and decreased angiostatin expression. PROX-1 overexpression also increased the phosphorylation of glycogen synthase kinase-3β (GSK-3β) and forkhead box O1 (FOXO1) in HCC cells. After PROX-1 knockdown, their phosphorylation was reversed.

CONCLUSION

PROX-1 overexpression is associated with the invasive and oncogenic phenotypes of human HCC cells via GSK-3β and FOXO1 phosphorylation.

Discovery of Potent Multikinase Type-II Inhibitors Targeting CDK5 in the DFG-out Inactive State with Promising Potential against Glioblastoma

Kinases have proven valuable targets in successful cancer drug discovery projects, but not yet for malignant brain tumors where type-II inhibition of cyclin-dependent kinase 5 (CDK5) stabilizing the DFG-out inactive state has potential for design of selective and clinically efficient drug candidates. In the absence of crystallographic evidence for a CDK5 DFG-out inactive state protein-ligand complex, for the first time, a model was designed using metadynamics/molecular dynamics simulations. Glide docking of the ZINC15 biogenic database identified [pyrimidin-2-yl]amino-furo[3,2-b]-furyl-urea/amide hit chemical scaffolds. For four selected analogues (4, 27, 36, and 42), potent effects on glioblastoma cell viability in U87-MG, T98G, and U251-MG cell lines and patient-derived cultures were generally observed (IC50s ∼ 10-40 μM at 72 h). Selectivity profiling against 11 homologous kinases revealed multikinase inhibition (CDK2, CDK5, CDK9, and GSK-3α/β), most potent for GSK-3α in the nanomolar range (IC50s ∼ 0.23-0.98 μM). These compounds may therefore have diverse anticancer mechanisms of action and are of considerable interest for lead optimization.

Parthenolide inhibits the proliferation and migration of cervical cancer cells via FAK/GSK3β pathway

PURPOSE

Cervical cancer (CC) ranks as the fourth most prevalent malignancy among women worldwide, necessitating effective therapeutic interventions to mitigate its detrimental impact on both physical and mental health. Parthenolide (PTL), a natural product of the sesquiterpene lactone derived from Feverfew leaves, has exhibited promising anti-tumor properties in previous studies; however, its precise effects and underlying molecular mechanisms in CC remain elusive.

METHODS

In this work, we investigated the effect of PTL on the proliferation and migration of CC cells. Western blot analysis and Reverse transcription‑quantitative PCR were used for mechanistic elucidation.

RESULTS

Our findings indicated that PTL substantially inhibited the proliferation of HeLa and SiHa CC cell lines in a dose- and time-dependent manner. Moreover, PTL significantly suppressed the migration of CC cells by down-regulating the expression of vascular endothelial growth factor (VEGF), metastasis-associated protein 1 (MTA1), and transforming growth factor-β1 (TGF-β1). Mechanistically, PTL blocked the phosphorylation of focal adhesion kinase (FAK) and glycogen synthase kinase-3β (GSK3β) induced by epidermal growth factor (EGF). Further investigations revealed that PTL suppressed the proliferation of CC cells by inhibiting the EGF-mediated phosphorylation of the FAK/GSK3β signaling pathway.

CONCLUSION

Taken together, the present in vitro results suggest that PTL may inhibit the proliferation and migration of CC cells through down-regulating the FAK/GSK3β signaling pathway, providing new insights for the application of PTL in the treatment of CC.

Glycogen synthase kinase 3β: the nexus of chemoresistance, invasive capacity, and cancer stemness in pancreatic cancer

The treatment of pancreatic cancer remains a significant clinical challenge due to the limited number of patients eligible for curative (R0) surgery, failures in the clinical development of targeted and immune therapies, and the pervasive acquisition of chemotherapeutic resistance. Refractory pancreatic cancer is typified by high invasiveness and resistance to therapy, with both attributes related to tumor cell stemness. These malignant characteristics mutually enhance each other, leading to rapid cancer progression. Over the past two decades, numerous studies have produced evidence of the pivotal role of glycogen synthase kinase (GSK)3β in the progression of over 25 different cancer types, including pancreatic cancer. In this review, we synthesize the current knowledge on the pathological roles of aberrant GSK3β in supporting tumor cell proliferation and invasion, as well as its contribution to gemcitabine resistance in pancreatic cancer. Importantly, we discuss the central role of GSK3β as a molecular hub that mechanistically connects chemoresistance, tumor cell invasion, and stemness in pancreatic cancer. We also discuss the involvement of GSK3β in the formation of desmoplastic tumor stroma and in promoting anti-cancer immune evasion, both of which constitute major obstacles to successful cancer treatment. Overall, GSK3β has characteristics of a promising therapeutic target to overcome chemoresistance in pancreatic cancer.

Exploring gene-patient association to identify personalized cancer driver genes by linear neighborhood propagation

BACKGROUND

Driver genes play a vital role in the development of cancer. Identifying driver genes is critical for diagnosing and understanding cancer. However, challenges remain in identifying personalized driver genes due to tumor heterogeneity of cancer. Although many computational methods have been developed to solve this problem, few efforts have been undertaken to explore gene-patient associations to identify personalized driver genes.

RESULTS

Here we propose a method called LPDriver to identify personalized cancer driver genes by employing linear neighborhood propagation model on individual genetic data. LPDriver builds personalized gene network based on the genetic data of individual patients, extracts the gene-patient associations from the bipartite graph of the personalized gene network and utilizes a linear neighborhood propagation model to mine gene-patient associations to detect personalized driver genes. The experimental results demonstrate that as compared to the existing methods, our method shows competitive performance and can predict cancer driver genes in a more accurate way. Furthermore, these results also show that besides revealing novel driver genes that have been reported to be related with cancer, LPDriver is also able to identify personalized cancer driver genes for individual patients by their network characteristics even if the mutation data of genes are hidden.

CONCLUSIONS

LPDriver can provide an effective approach to predict personalized cancer driver genes, which could promote the diagnosis and treatment of cancer. The source code and data are freely available at https://github.com/hyr0771/LPDriver .

Hydroalcoholic root extracts of Houttuynia cordata (Thunb.) standardized by UPLC-Q-TOF-MS/MS promotes apoptosis in human hepatocarcinoma cell HepG2 via GSK-3β/β-catenin/PDL-1 axis

Houttuynia cordata (Thunb.), an important medicinal plant of Northeast India, Korea, and China, is used to treat various ailments and for anticancer research. Knowing its traditional practices, we are interested in the mode-of-action of HCT on HepG2 to co-relate the traditional practice with modern drug therapeutics. UPLC-Q-ToF-Ms analysis of HCT reveals identification of 14 metabolites. Network pharmacology analysis of the 14 compounds showed interaction with 232 different targets with their potential involvement in hepatocellular carcinoma. Whole extracts impart cytotoxicity on variety of cell lines including HepG2. There was a significant morphological alteration in treated HepG2 cells due to impairment of cytoskeletal components like β and γ- tubulin. Arrest at G1-S checkpoint was clearly indicated downregulation of Cyclin D1. The root extracts actuated apoptosis in HepG2 as evident from altered mitochondrial membrane potential, Annexin V- FITC, BrdU-PI, AO/EtBr assays, and modulations of apoptotic protein expression but without ROS generation. Whole extracts caused abrogation of epithelial to mesenchymal transition with repression of Snail, N-Cadherin, Vimentin, MMP-9, and upregulation of Pan-Cadherin. Pathway analysis found GSK-3β in Wnt/β-Catenin signaling cascade to be involved through Hepatocellular carcinoma (hsa05225) pathway. The GSK-3β/β-Catenin/PDL-1 signaling was found to be inhibited with the downregulation of pathway components. This was further confirmed by application of EGF, an inducer of the GSK-3β/β-Catenin pathway that neutralized the effect of Houttuynia cordata (Thunb.) root extract on the said pathway. Network pharmacology analysis also confirms the synergy network with botanical-bioactive-target-disease which showed Kaempferol to have the highest degree of association with the said pathway.

When You Come to a Fork in the Road, Take It: Wnt Signaling Activates Multiple Pathways through the APC/Axin/GSK-3 Complex

The Wnt signaling pathway is a highly conserved regulator of metazoan development and stem cell maintenance. Activation of Wnt signaling is an early step in diverse malignancies. Work over the past four decades has defined a "canonical" Wnt pathway that is initiated by Wnt proteins, secreted glycoproteins that bind to a surface receptor complex and activate intracellular signal transduction by inhibiting a catalytic complex composed of the classical tumor suppressor Adenomatous Polyposis Coli (APC), Axin, and Glycogen Synthase Kinase-3 (GSK-3). The best characterized effector of this complex is β-catenin, which is stabilized by inhibition of GSK-3, allowing β-catenin entrance to the nucleus and activation of Wnt target gene transcription, leading to multiple cancers when inappropriately activated. However, canonical Wnt signaling through the APC/Axin/GSK-3 complex impinges on other effectors, independently of β-catenin, including the mechanistic Target of Rapamycin (mTOR), regulators of protein stability, mitotic spindle orientation, and Hippo signaling. This review focuses on these alternative effectors of the canonical Wnt pathway and how they may contribute to cancers.

Perioperative opioids and survival outcomes in resectable head and neck cancer: A systematic review

BACKGROUND

Opioids are a mainstay in pain control for oncologic surgery. The objective of this systematic review is to evaluate the associations of perioperative opioid use with overall survival (OS) and disease-free survival (DFS) in patients with resectable head and neck cancer (HNC).

METHODS

A systematic review of PubMed, SCOPUS, and CINAHL between 2000 and 2022 was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Studies investigating perioperative opioid use for patients with HNC undergoing surgical resection and its association with OS and DFS were included.

RESULTS

Three thousand three hundred seventy-eight studies met initial inclusion criteria, and three studies representing 562 patients (intraoperative opioids, n = 463; postoperative opioids, n = 99) met final exclusion criteria. One study identified that high intraoperative opioid requirement in oral cancer surgery was associated with decreased OS (HR = 1.77, 95% CI 0.995-3.149) but was not an independent predictor of decreased DFS. Another study found that increased intraoperative opioid requirements in treating laryngeal cancer was demonstrated to have a weak but statistically significant inverse relationship with DFS (HR = 1.001, p = 0.02) and OS (HR = 1.001, p = 0.02). The last study identified that patients with chronic opioid after resection of oral cavity cancer had decreased DFS (HR = 2.7, 95% CI 1.1-6.6) compared to those who were not chronically using opioids postoperatively.

CONCLUSION

An association may exist between perioperative opioid use and OS and DFS in patients with resectable HNC. Additional investigation is required to further delineate this relationship and promote appropriate stewardship of opioid use with adjunctive nonopioid analgesic regimens.

In vitro analysis of PI3K pathway activation genes for exploring novel biomarkers and therapeutic targets in clear cell renal carcinoma

OBJECTIVES

The regulation of various cellular functions such as growth, proliferation, metabolism, and angiogenesis, is dependent on the PI3K pathway. Recent evidence has indicated that kidney renal clear cell carcinoma (KIRC) can be triggered by the deregulation of this pathway. The objective of this research was to investigate 25 genes associated with activation of the PI3K pathway in KIRC and control samples to identify four hub genes that might serve as novel molecular biomarkers and therapeutic targets for treating KIRC.

METHODS

Multi-omics in silico and in vitro analysis was employed to find hub genes related to the PI3K pathway that may be biomarkers and therapeutic targets for KIRC.

RESULTS

Using STRING software, a protein-protein interaction (PPI) network of 25 PI3K pathway-related genes was developed. Based on the degree scoring method, the top four hub genes were identified using Cytoscape's Cytohubba plug-in. TCGA datasets, KIRC (786-O and A-498), and normal (HK2) cells were used to validate the expression of hub genes. Additionally, further bioinformatic analyses were performed to investigate the mechanisms by which hub genes are involved in the development of KIRC. Out of a total of 25 PI3K pathway-related genes, we developed and validated a diagnostic and prognostic model based on the up-regulation of TP53 (tumor protein 53) and CCND1 (Cyclin D1) and the down-regulation of PTEN (Phosphatase and TENsin homolog deleted on chromosome 10), and GSK3B (Glycogen synthase kinase-3 beta) hub genes. The hub genes included in our model may be a novel therapeutic target for KIRC treatment. Additionally, associations between hub genes and infiltration of immune cells can enhance comprehension of immunotherapy for KIRC.

CONCLUSION

We have created a new diagnostic and prognostic model for KIRC patients that uses PI3K pathway-related hub genes (TP53, PTEN, CCND1, and GSK3B). Nevertheless, further experimental studies are required to ascertain the efficacy of our model.

Phytochemical Analysis, In Vitro Biological Activities, and Computer-Aided Analysis of Potentilla nepalensis Hook Compounds as Potential Melanoma Inhibitors Based on Molecular Docking, MD Simulations, and ADMET

Potentilla nepalensis Hook is a perennial Himalayan medicinal herb of the Rosaceae family. The present study aimed to evaluate biological activities such as the antioxidant, antibacterial, and anticancer activities of roots and shoots of P. nepalensis and its synergistic antibacterial activity with antibacterial drugs. Folin-Ciocalteau and aluminium chloride methods were used for the calculation of total phenolic (TPC) and flavonoid content (TFC). A DPPH radical scavenging assay and broth dilution method were used for the determination of the antioxidant and antibacterial activity of the root and shoot extracts of P. nepalensis. Cytotoxic activity was determined using a colorimetric MTT assay. Further, phytochemical characterization of the root and shoot extracts was performed using the Gas chromatography-mass spectrophotometry (GC-MS) method. The TPC and TFC were found to be higher in the methanolic root extract of P. nepalensis. The methanolic shoot extract of P. nepalensis showed good antioxidant activity, while then-hexane root extract of P. nepalensis showed strong cytotoxic activity against tested SK-MEL-28 cells. Subsequently, in silico molecular docking studies of the identified bioactive compounds predicted potential anticancer properties. This study can lead to the production of new herbal medicines for various diseases employing P. nepalensis, leading to the creation of new medications.

Identifying promising GSK3β inhibitors for cancer management: a computational pipeline combining virtual screening and molecular dynamics simulations

Glycogen synthase kinase-3 (GSK3β), a serine/threonine protein kinase, has been discovered as a novel target for anticancer drugs. Although GSK3β is involved in multiple pathways linked to the etiology of various cancers, no specific GSK3β inhibitor has been authorized for cancer therapy. Most of its inhibitors have toxicity effects therefore, there is a need to develop safe and more potent inhibitors. In this study, a library of 4,222 anti-cancer compounds underwent rigorous computational screening to identify potential candidates for targeting the binding pocket of GSK3β. The screening process involved various stages, including docking-based virtual screening, physicochemical and ADMET analysis, and molecular dynamics simulations. Ultimately, two hit compounds, BMS-754807 and GSK429286A, were identified as having high binding affinities to GSK3β. BMS-754807 and GSK429286A exhibited binding affinities of -11.9, and -9.8 kcal/mol, respectively, which were greater than that of the positive control (-7.6 kcal/mol). Further, molecular dynamics simulations for 100 ns were employed to optimize the interaction between the compounds and GSK3β, and the simulations demonstrated that the interaction was stable and consistent throughout the study. These hits were also anticipated to have good drug-like properties. Finally, this study suggests that BMS-754807 and GSK429286A may undergo experimental validation to evaluate their potential as cancer treatments in clinical settings.

In Silico-Motivated Discovery of Novel Potent Glycogen Synthase-3 Inhibitors: 1-(Alkyl/arylamino)-3H-naphtho[1,2,3-de]quinoline-2,7-dione Identified as a Scaffold for Kinase Inhibitor Development

Glycogen synthase kinase-3 (GSK-3) isoforms α and β have diverse roles within cell biology, and have been linked with multiple diseases that include prominent CNS conditions such as Alzheimer's disease and several psychiatric disorders. In this study, motivated by computation, we aimed to identify novel ATP-binding site inhibitors of GSK-3 with CNS-active potential. A ligand screening (docking) protocol against GSK-3β was first optimized, employing an active/decoy benchmarking set, with the final protocol selected based on statistical performance analysis. The optimized protocol involved pre-filtering of ligands using a three-point 3D-pharmacophore, followed by Glide-SP docking applying hinge region hydrogen bonding constraints. Using this approach, the Biogenic subset of the ZINC15 compound database was screened, focused on compounds with potential for CNS-activity. Twelve compounds (generation I) were selected for experimental validation using in vitro GSK-3β binding assays. Two hit compounds, 1 and 2, with 6-amino-7H-benzo[e]perimidin-7-one and 1-(phenylamino)-3H-naphtho[1,2,3-de]quinoline-2,7-dione type scaffolds were identified with IC₅₀ values of 1.63 µM and 20.55 µM, respectively. Ten analogues of 2 (generation II) were selected for structure activity relationship (SAR) analysis and revealed four low micromolar inhibitors (<10 µM), with 19 (IC₅₀ = 4.1 µM)~five times more potent than initial hit compound 2. Selectivity screening of low micromolar inhibitors 14 and 19 (comparing aryl- and alkyl-substituents) against 10 homologous kinases revealed unique selectivity profiles, with both compounds more potent against the GSK-3α isoform (IC₅₀s~2 µM) and, additionally, inhibitors of PKBβ (IC₅₀s < 25 µM). Compound 14 also inhibited ERK2 and 19, PKCγ, but generally good selectivity for GSK-3 isoforms over the other kinases was observed. The compounds had excellent predicted oral bioavailability and CNS-activity profiles, presenting promising candidates for future testing in cellular models of disease.

4-[(5-Methyl-1H-pyrazol-3-yl)amino]-2H-phenyl-1-phthalazinone Inhibits MCPyV T Antigen Expression in Merkel Cell Carcinoma Independent of Aurora Kinase A

Merkel cell carcinoma (MCC) is frequently caused by the Merkel cell polyomavirus (MCPyV), and MCPyV-positive tumor cells depend on expression of the virus-encoded T antigens (TA). Here, we identify 4-[(5-methyl-1H-pyrazol-3-yl)amino]-2H-phenyl-1-phthalazinone (PHT)-a reported inhibitor of Aurora kinase A-as a compound inhibiting growth of MCC cells by repressing noncoding control region (NCCR)-controlled TA transcription. Surprisingly, we find that TA repression is not caused by inhibition of Aurora kinase A. However, we demonstrate that β-catenin-a transcription factor repressed by active glycogen synthase kinase 3 (GSK3)-is activated by PHT, suggesting that PHT bears a hitherto unreported inhibitory activity against GSK3, a kinase known to function in promoting TA transcription. Indeed, applying an in vitro kinase assay, we demonstrate that PHT directly targets GSK3. Finally, we demonstrate that PHT exhibits in vivo antitumor activity in an MCC xenograft mouse model, suggesting a potential use in future therapeutic settings for MCC.

GSK-3β Allosteric Inhibition: A Dead End or a New Pharmacological Frontier?

Most kinase inhibitors are designed to bind to highly homologous ATP-binding sites, which leads to promiscuity and possible off-target effects. Allostery is an alternative approach to pursuing selectivity. However, allostery is difficult to exploit due to the wide variety of underlying mechanisms and the potential involvement of long-range conformational effects that are difficult to pinpoint. GSK-3β is involved in several pathologies. This critical target has an ATP-binding site that is highly homologous with the orthosteric sites of other kinases. Unsurprisingly, there is also great similarity between the ATP-binding sites of GSK-3β and its isomer, which is not redundant and thus would benefit from selective inhibition. Allostery would also allow for a moderate and tunable inhibition, which is ideal for GSK-3β, because this target is involved in multiple pathways, some of which must be preserved. However, despite considerable research efforts, only one allosteric GSK-3β inhibitor has reached the clinic. Moreover, unlike other kinases, there are no X-ray structures of GSK-3β in complex with allosteric inhibitors in the PDB data bank. This review aims to summarize the state of the art in allosteric GSK-3β inhibitor investigations, highlighting the aspects that make this target challenging for an allosteric approach.

Molecular docking, molecular dynamics simulations and in vitro screening reveal cefixime and ceftriaxone as GSK3β covalent inhibitors

GSK3β is a serine/threonine kinase that has been suggested as a putative drug target for several diseases. Recent studies have reported the beneficial effects of cephalosporin antibiotics in cancer and Alzheimer's disease, implying potential inhibition of GSK3β. To investigate this mechanism, four cephalosporins, namely, cefixime, ceftriaxone, cephalexin and cefadroxil were docked into the GSK3β binding pocket. The third-generation cephalosporins, cefixime and ceftriaxone, exhibited the best docking scores due to the exclusive hydrogen bonding between their aminothiazole group and hinge residues of GSK3β. The stability of top-ranked poses and the possibility of covalent bond formation between the carbonyl carbon of the β-lactam ring and the nucleophilic thiol of Cys-199 were evaluated by molecular dynamics simulations and covalent docking. Finally, the in vitro inhibitory activities of the four cephalosporins were measured against GSK3β with and without preincubation. In agreement with the results of molecular docking, cefixime and ceftriaxone exhibited the best inhibitory activities with IC₅₀ values of 2.55 μM and 7.35 μM, respectively. After 60 minutes preincubation with GSK3β, the IC₅₀ values decreased to 0.55 μM for cefixime and 0.78 μM for ceftriaxone, supporting a covalent bond formation as suggested by molecular dynamics simulations and covalent docking. In conclusion, the third-generation cephalosporins are reported herein as GSK3β covalent inhibitors, offering insight into the mechanism behind their benefits in cancer and Alzheimer's disease.

High Throughput Confined Migration Microfluidic Device for Drug Screening

Cancer metastasis is the major cause of cancer-related death. Excessive extracellular matrix deposition and increased stiffness are typical features of solid tumors, creating confined spaces for tumor cell migration and metastasis. Confined migration is involved in all metastasis steps. However, confined and unconfined migration inhibitors are different and drugs available to inhibit confined migration are rare. The main challenges are the modeling of confined migration, the suffering of low throughput, and others. Microfluidic device has the advantage to reduce reagent consumption and enhance throughput. Here, a microfluidic chip that can achieve multi-function drug screening against the collective migration of cancer cells under confined environment is designed. This device is applied to screen out effective drugs on confined migration among a novel mechanoreceptors compound library (166 compounds) in hepatocellular carcinoma, non-small lung cancer, breast cancer, and pancreatic ductal adenocarcinoma cells. Three compounds that can significantly inhibit confined migration in pan-cancer: mitochonic acid 5 (MA-5), SB-705498, and diphenyleneiodonium chloride are found. Finally, it is elucidated that these drugs targeted mitochondria, actin polymerization, and cell viability, respectively. In sum, a high-throughput microfluidic platform for screening drugs targeting confined migration is established and three novel inhibitors of confined migration in multiple cancer types are identified.

GSK-3β phosphorylation of DHX33 leads to its ubiquitination mediated protein degradation

DHX33 is a member of DEAD/H box protein family, and is involved in both RNA and DNA metabolism. It plays diverse roles in multiple cellular activities. DHX33 overexpression has been found to promote the development of many human cancers. However, the underlying mechanism to explain its high expression in cancer cells remains incompletely resolved. In this study, with both human cancer cell lines and normal fibroblasts, we found glycogen synthase kinase 3β (GSK-3β) regulates DHX33 protein stability. This is through its direct phosphorylation of DHX33 on T482, which triggers ubiquitination mediate protein degradation. We further identified one of the major ubiquitination sites of DHX33 to be on its N-terminal K94, a critical residue previously found to be important and highly conserved for ATP binding and helicase activity. Our study for the first time reveals an important upstream regulator, GSK-3β, as a critical kinase to phosphorylate DHX33 at the post-translational level leading to its degradation. Moreover, cancer cells have frequent GSK3β deactivation to disrupt this signaling cascade. Therefore, DHX33 is stabilized in many cancer cells as compared to normal cells. Our study unveils an important post-translational regulation of DHX33 in cells and further unveils a novel mechanism for DHX33 overexpression in cancer cells.

Imidazole-pyridine hybrids as potent anti-cancer agents

In the current investigation, fifteen novel imidazole-pyridine-based molecules were synthesized and tested against cell lines of the lung (H1299) and colon (HCT116) adenocarcinomas by proliferation assay. The results demonstrated that compounds 5a, 5d, 5e, and 5f were the most active (IC₅₀<30 µM). Based on recent literature and the current results, the glycogen synthase kinase-3β (GSK-3β) protein was investigated in-silico as a possible target. The molecular docking and QSAR revealed an excellent binding affinity of the selected imidazole-pyridine compounds to GSK-3β. Notably, GSK-3β protein levels were significantly upregulated in hepatocellular liver carcinoma (LIHCs) tissues and negatively affected patient prognosis. Consequently, the compounds were evaluated on liver cancer cell lines (HepG2, HUH-7, and PLC/PRF/5) by the MTT assay, and 5d showed the highest antitumor activity. This study offers new compounds with interesting biological activity on GSK-3β as a target, exhibiting a potential therapeutic impact for hepatocellular carcinoma patients.

Design, synthesis and biological evaluation of a novel colchicine-magnolol hybrid for inhibiting the growth of Lewis lung carcinoma in Vitro and in Vivo

Colchicine is a bioactive alkaloid originally from Colchicum autumnale and possesses excellent antiproliferative activity. However, colchicine-associated severe toxicity, gastrointestinal side effects in particular, limits its further therapeutic use. In the current study, we thus designed and synthesized a novel hybrid (CMH) by splicing colchicine and magnolol, a multifunctional polyphenol showing favorable gastrointestinal protection. The antitumor activity of CMH in Lewis lung carcinoma (LLC) was then evaluated in vitro and in vivo. Biologically, CMH inhibited the growth of LLC cells with an IC₅₀ of 0.26 μM, 100 times more potently than cisplatin (26.05 μM) did. Meanwhile, the cytotoxicity of CMH was 10-fold lower than that of colchicine in normal human lung cells (BEAS-2B). In C57BL/6 mice xenograft model, CMH (0.5 mg/kg) worked as efficacious as colchicine (0.5 mg/kg) to inhibit tumor growth and 2 times more potently than cisplatin (1 mg/kg). In terms of mortality, 7 out of 10 mice died in colchicine group (0.75 mg/kg), while no death was observed in groups receiving CMH or cisplatin at 0.75 mg/kg. Mechanistic studies using Western blot revealed that CMH dose-dependently suppressed the protein expression of phosphorylated ERK. Molecular docking analysis further indicated that CMH was well fitted in the colchicine binding site of tubulin and formed several hydrogen bonds with tubulin protein. These results enable our novel hybrid CMH as a potential antineoplastic agent with lower toxicity, and provide perquisites for further investigation to confirm the therapeutic potentiality of this novel hybrid.

Programmed death-ligand 1 signaling and expression are reversible by lycopene via PI3K/AKT and Raf/MEK/ERK pathways in tongue squamous cell carcinoma

Background

Cancer therapy targeting programmed death receptor-1 (PD-1 or CD279) or programmed death-ligand 1 (PD-L1 or CD274) gives hope to Tongue Squamous Cell Carcinoma (TSCC) treatment. However, the tumor-intrinsic mechanism of PD-L1 is not fully elucidated in TSCC. On the other hand, lycopene showed antitumor effects and chemotherapy/radiotherapy-enhancing effects by mechanisms closely correlated with PD-L1.

Purpose

We aimed to explore whether the mechanisms of PD-L1 signaling and regulation are reversible by lycopene treatment in TSCC.

Methods

We collected TSCC tissues and normal tissues for assessment of PD-L1 expression by immunohistochemical technique and western blotting. We measured the expression of PD-L1 in three TSCC cell lines and constructed cell lines with knockdown and overexpression of PD-L1. Then, we measured the proliferation by CCK-8 assay, migration and invasion by Transwell assay, and apoptosis by TUNEL assay in five groups with treatment of blank control, negative control with vector transfection, PD-L1 knockdown/overexpression, 4 μM lycopene, and combined 4 μM lycopene and PD-L1 knockdown/overexpression. We also systematically analyzed the PD-L1 constitutive signaling pathways and their effect EMT pathways. In order to bring out the mechanism underlying PI3K/AKT depressing Raf/MEK/ERK, we used PI3K inhibitor LY294002.

Results

We detected significant PD-L1 upregulation in biopsies by western blot and immunohistochemistry. Our study demonstrated that PD-L1 upregulation elevated IGF-1R to activate the PI3K/AKT pathway but inactivated the Raf/MEK/ERK pathway in TSCC cell line CAL27, while PD-L1 knockdown decreased IGF-1R to inactivate both PI3K/AKT and Raf/MEK/ERK pathways in cell line SCC9, to increase/decrease p-FOXOs and decrease/increase p-GSK-3β, producing further changes in EMT, proliferation, migration, invasion, and apoptosis. Lycopene reversed PD-L1 signaling and expression by mechanisms opposite to PD-L1 upregulation but similar to PD-L1 knockdown.

Conclusion

Taken together, this study firstly confirmed PD-L1 expression and signaling are reversible by lycopene via PI3K/AKT and Raf/MEK/ERK pathways in TSCC. Our study provides a sounder basis for comprehending PD-L1 signaling and expression and prevention and treatment of TSCC.

Glycogen Synthase Kinase 3β: A True Foe in Pancreatic Cancer

Glycogen synthase kinase 3 beta (GSK-3β) is a serine/threonine protein kinase involved in multiple normal and pathological cell functions, including cell signalling and metabolism. GSK-3β is highly expressed in the onset and progression of multiple cancers with strong involvement in the regulation of proliferation, apoptosis, and chemoresistance. Multiple studies showed pro- and anti-cancer roles of GSK-3β creating confusion about the benefit of targeting GSK-3β for treating cancer. In this mini-review, we focus on the role of GSK-3β in pancreatic cancer. We demonstrate that the proposed anti-cancer roles of GSK-3β are not relevant to pancreatic cancer, and we argue why GSK-3β is, indeed, a very promising therapeutic target in pancreatic cancer.

Quercetin Suppresses Human Glioblastoma Migration and Invasion via GSK3β/β-catenin/ZEB1 Signaling Pathway

High invasiveness is a biological and clinical characteristic of glioblastoma and predicts poor prognosis of patients. Quercetin, a natural flavonoid compound, exhibits anticancer activity. However, we have a limited understanding of the possible underlying mechanism of quercetin in glioblastoma. In this study, we investigated the anticancer effect of quercetin in human glioblastoma cells. Our results showed that quercetin markedly suppressed the viability of glioblastoma cells in vitro and in vivo, and significantly inhibited glioblastoma cell migration and invasion. Moreover, quercetin reversed EMT-like mesenchymal phenotype and reduced the expression levels of EMT-related markers. Furthermore, we found that quercetin suppressed GSK-3β/β-catenin/ZEB1 signaling in glioblastoma. Taken together, our results demonstrate that quercetin inhibited migration and invasion of human glioma cells by suppressing GSK3β/β-catenin/ZEB1 signaling. Our study provides evidence that quercetin is a promising therapeutic natural compound to treat glioblastoma.

E6E7 regulates the HK2 expression in cervical cancer via GSK3β/FTO signal

BACKGROUND

Cervical cancer is one of the most common cancers in women worldwide. Hexokinase 2 (HK2) is responsible for phosphorylating glucose into glucose-6-phosphate, which is required for tumorigenesis and metastasis.

METHODS

E6E7 and FTO were exogenously expressed, and their effects on HK2 mRNA and protein levels were detected by RT-qPCR and Western blot.

RESULTS

The exogenous expression of E6E7 in SiHa and C33A cells up-regulated the mRNA and protein levels of intracellular HK2, up-regulated the total m⁶A levels, changed the expression of m⁶A proteins and activated the GSK3β transcription. The expression levels of METTL3 and WTAP were enhanced, whereas the expression of FTO and ALKBH5 were decreased. In addition, FTO down-regulated the mRNA and protein levels of HK2. FTO overexpression partially inhibited the up-regulated expression of HK2 caused by E6E7. Furthermore, FTO overexpression increased the level of HK2 pre-mRNA in the nucleus and decreased the level of mature HK2 mRNA in the cytoplasm. We also found that GSK3β overexpression enhanced FTO ubiquitination and decreased FTO protein levels.

CONCLUSION

This study found that E6E7 oncogene activates the transcription of GSK3β; GSK3β can promote the ubiquitination-proteasomal degradation of FTO and reduce the level of FTO protein; FTO inhibits the maturation and translation of HK2 mRNA by retaining HK2 pre-mRNA in the nucleus.

Liposomes Loaded with Amaranth Unsaponifiable Matter and Soybean Lunasin Prevented Melanoma Tumor Development Overexpressing Caspase-3 in an In Vivo Model

The objective of this study was to assess the effectiveness of liposomes loaded with soybean lunasin and amaranth unsaponifiable matter (UM + LunLip) as a source of squalene in the prevention of melanoma skin cancer in an allograft mice model. Tumors were induced by transplanting melanoma B16-F10 cells into the mice. The most effective treatments were those including UM + LunLip, with no difference between the lunasin concentrations (15 or 30 mg/kg body weight); however, these treatments were statistically different from the tumor-bearing untreated control (G3) (p < 0.05). The groups treated with topical application showed significant inhibition (68%, p < 0.05) compared to G3. The groups treated with subcutaneous injections showed significant inhibition (up to 99%, p < 0.05) in G3. During tumor development, UM + LunLip treatments under-expressed Ki-67 (0.2-fold compared to G3), glycogen synthase kinase-3β (0.1-fold compared to G3), and overexpressed caspase-3 (30-fold compared to G3). In addition, larger tumors showed larger necrotic areas (38% with respect to the total tumor) (p < 0.0001). In conclusion, the UM + LunLip treatment was effective when applied either subcutaneously or topically in the melanoma tumor-developing groups, as it slowed down cell proliferation and activated apoptosis.

Targeting neuronal calcium channels and GSK3β for Alzheimer's disease with naturally-inspired Diels-Alder adducts

The complexity of neurodegenerative diseases, among which Alzheimer's disease plays a pivotal role, poses one of the tough therapeutic challenges of present time. In this perspective, a multitarget approach appears as a promising strategy to simultaneously interfere with different defective pathways. In this paper, a structural simplification plan was performed on our previously reported multipotent polycyclic compounds, in order to obtain a simpler pharmacophoric central core with improved pharmacokinetic properties, while maintaining the modulating activity on neuronal calcium channels and glycogen synthase kinase 3-beta (GSK-3β), as validated targets to combat Alzheimer's disease. The molecular pruning approach applied here led to tetrahydroisoindole-dione (1), tetrahydromethanoisoindole-dione (2) and tetrahydroepoxyisoindole-dione (3) structures, easily affordable by Diels-Alder cycloaddition. Preliminary data indicated structure 3 as the most appropriate, thus a SAR study was performed by introducing different substituents, selected on the basis of the commercial availability of the furan derivatives required for the synthetic procedure. The results indicated compound 10 as a promising, structurally atypical, safe and BBB-penetrating Ca_v modulator, inhibiting both L- and N-calcium channels, likely responsible for the Ca²⁺ overload observed in Alzheimer's disease. In a multitarget perspective, compound 11 appeared as an effective prototype, endowed with improved Ca_v inhibitory activity, with respect to the reference drug nifedipine, and encouraging modulating activity on GSK-3β.

PRMT5 acts as a tumor suppressor by inhibiting Wnt/β-catenin signaling in murine gastric tumorigenesis

Previous studies have demonstrated the in vitro oncogenic role of protein arginine methyltransferase 5 (PRMT5) in gastric cancer cell lines. The in vivo function of PRMT5 in gastric tumorigenesis, however, is still unexplored. Here, we showed that Prmt5 deletion in mouse gastric epithelium resulted in spontaneous tumorigenesis in gastric antrum. All Prmt5-deficient mice displayed intestinal-type gastric cancer within 4 months of age. Of note, 20% (2/10) of Prmt5 mutants finally developed into invasive gastric cancer by 8 months of age. Gastric cancer caused by PRMT5 loss exhibited the increase in Lgr5⁺ stem cells, which are proposed to contribute to both the gastric tumorigenesis and progression in mouse models. Consistent with the notion that Lgr5 is the target of Wnt/β-catenin signaling, whose activation is the most predominant driver for gastric tumorigenesis, Prmt5 mutant gastric cancer showed the activation of Wnt/β-Catenin signaling. Furthermore, in human gastric cancer samples, PRMT5 deletion and downregulation were frequently observed and associated with the poor prognosis. We propose that as opposed to the tumor-promoting role of PRMT5 well-established in the progression of various cancer types, PRMT5 functions as a tumor suppressor in vivo, at least during gastric tumor formation.

Combination Approaches to Target PD-1 Signaling in Cancer

Cancer remains the second leading cause of death in the US, accounting for 25% of all deaths nationwide. Immunotherapy techniques bolster the immune cells' ability to target malignant cancer cells and have brought immense improvements in the field of cancer treatments. One important inhibitory protein in T cells, programmed cell death protein 1 (PD-1), has become an invaluable target for cancer immunotherapy. While anti-PD-1 antibody therapy is extremely successful in some patients, in others it fails or even causes further complications, including cancer hyper-progression and immune-related adverse events. Along with countless translational studies of the PD-1 signaling pathway, there are currently close to 5,000 clinical trials for antibodies against PD-1 and its ligand, PD-L1, around 80% of which investigate combinations with other therapies. Nevertheless, more work is needed to better understand the PD-1 signaling pathway and to facilitate new and improved evidence-based combination strategies. In this work, we consolidate recent discoveries of PD-1 signaling mediators and their therapeutic potential in combination with anti-PD-1/PD-L1 agents. We focus on the phosphatases SHP2 and PTPN2; the kinases ITK, VRK2, GSK-3, and CDK4/6; and the signaling adaptor protein PAG. We discuss their biology both in cancer cells and T cells, with a focus on their role in relation to PD-1 to determine their potential in therapeutic combinations. The literature discussed here was obtained from a search of the published literature and ClinicalTrials.gov with the following key terms: checkpoint inhibition, cancer immunotherapy, PD-1, PD-L1, SHP2, PTPN2, ITK, VRK2, CDK4/6, GSK-3, and PAG. Together, we find that all of these proteins are logical and promising targets for combination therapy, and that with a deeper mechanistic understanding they have potential to improve the response rate and decrease adverse events when thoughtfully used in combination with checkpoint inhibitors.

Molecular docking study of GSK-3β interaction with nomilin, kihadanin B, and related limonoids and triterpenes with a furyl-δ-lactone core

Glycogen synthase kinase-3β (GSK-3β) is a target enzyme considered for the treatment of multiple human diseases, from neurodegenerative pathologies to viral infections and cancers. Numerous inhibitors of GSK-3β have been discovered but thus far only a few have reached clinical trials and only one drug, tideglusib (1), has been registered. Natural products targeting GSK-3β have been identified, including the two anticancer limonoids obacunone (5) and gedunin (4), both presenting a furyl-δ-lactone core. To help identifying novel GSK-3β ligands, we have performed a molecular docking study with 15 complementary natural products bearing a furyl-δ-lactone unit (such as limonin (6) and kihadanins A (8) and B (9)) or a closely related structure (such as cedrelone (10) and nimbolide (11)). The formation of GSK-3β-binding complexes for those natural products was compared to reference GSK-3β ATP-competitive inhibitors LY2090314 (3) and AR-A014418 (2). Our in silico analysis led to the identification of two new GSK-3β-binding natural products: kihadanin B (9) and nomilin (7). The latter surpassed the reference compounds in terms of calculated empirical energy of interaction (ΔE). Nomilin (7) can possibly bind to the active site of GSK-3β, notably via the furyl-δ-lactone core and its 1-acetyl group, implicated in the protein interaction. Compound structure-binding relationships are discussed. The study should help the discovery of novel natural products targeting GSK-3β.

SAR Probing of KX2-391 Provided Analogues With Juxtaposed Activity Profile Against Major Oncogenic Kinases

Tirbanibulin (KX2-391, KX-01), a dual non-ATP (substrate site) Src kinase and tubulin-polymerization inhibitor, demonstrated a universal anti-cancer activity for variety of cancer types. The notion that KX2-391 is a highly selective Src kinase inhibitor have been challenged by recent reports on the activities of this drug against FLT3-ITD mutations in some leukemic cell lines. Therefore, we hypothesized that analogues of KX2-391 may inhibit oncogenic kinases other than Src. A set of 4-aroylaminophenyl-N-benzylacetamides were synthesized and found to be more active against leukemia cell lines compared to solid tumor cell lines. N-(4-(2-(benzylamino)-2-oxoethyl)phenyl)-4-chlorobenzamide (4e) exhibited activities at IC₅₀ 0.96 µM, 1.62 µM, 1.90 µM and 4.23 µM against NB4, HL60, MV4-11 and K562 leukemia cell lines, respectively. We found that underlying mechanisms of 4e did not include tubulin polymerization or Src inhibition. Such results interestingly suggested that scaffold-hopping of KX2-391 may change the two main underlying cytotoxic mechanisms (Src and tubulin). Kinase profiling using two methods revealed that 4e significantly reduces the activities of some other potent oncogenic kinases like the MAPK member ERK1/2 (>99%) and it also greatly upregulates the pro-apoptotic c-Jun kinase (84%). This research also underscores the importance of thorough investigation of total kinase activities as part of the structure-activity relationship studies.

Tracing the origins of glioblastoma by investigating the role of gliogenic and related neurogenic genes/signaling pathways in GBM development: a systematic review

Background

Glioblastoma is one of the most aggressive tumors. The etiology and the factors determining its onset are not yet entirely known. This study investigates the origins of GBM, and for this purpose, it focuses primarily on developmental gliogenic processes. It also focuses on the impact of the related neurogenic developmental processes in glioblastoma oncogenesis. It also addresses why glial cells are at more risk of tumor development compared to neurons.

Methods

Databases including PubMed, MEDLINE, and Google Scholar were searched for published articles without any date restrictions, involving glioblastoma, gliogenesis, neurogenesis, stemness, neural stem cells, gliogenic signaling and pathways, neurogenic signaling and pathways, and astrocytogenic genes.

Results

The origin of GBM is dependent on dysregulation in multiple genes and pathways that accumulatively converge the cells towards oncogenesis. There are multiple layers of steps in glioblastoma oncogenesis including the failure of cell fate-specific genes to keep the cells differentiated in their specific cell types such as p300, BMP, HOPX, and NRSF/REST. There are genes and signaling pathways that are involved in differentiation and also contribute to GBM such as FGFR3, JAK-STAT, and hey1. The genes that contribute to differentiation processes but also contribute to stemness in GBM include notch, Sox9, Sox4, c-myc gene overrides p300, and then GFAP, leading to upregulation of nestin, SHH, NF-κB, and others. GBM mutations pathologically impact the cell circuitry such as the interaction between Sox2 and JAK-STAT pathway, resulting in GBM development and progression.

Conclusion

Glioblastoma originates when the gene expression of key gliogenic genes and signaling pathways become dysregulated. This study identifies key gliogenic genes having the ability to control oncogenesis in glioblastoma cells, including p300, BMP, PAX6, HOPX, NRSF/REST, LIF, and TGF beta. It also identifies key neurogenic genes having the ability to control oncogenesis including PAX6, neurogenins including Ngn1, NeuroD1, NeuroD4, Numb, NKX6-1 Ebf, Myt1, and ASCL1. This study also postulates how aging contributes to the onset of glioblastoma by dysregulating the gene expression of NF-κB, REST/NRSF, ERK, AKT, EGFR, and others.

Phosphorylation of small kinetochore-associated protein induced by GSK3β promotes cell migration and invasion in esophageal cancer

Glycogen synthesis kinase-3β (GSK-3β) is a kinase shown to regulate esophageal cancer (EC) progression. However, the significance of GSK-3β in phosphorylation of small kinetochore-associated protein (SKAP) has not been fully characterized. GSK-3β/SKAP expression was analyzed in EC tissues by RT-qPCR. The association between GSK-3β expression and the overall survival was analyzed using the Kaplan-Meier method. Transwell and wound healing assays were performed to assess the effects of GSK-3β/SKAP knockdown on EC cell migration and invasion. By in vitro kinase assay, the SKAP T294 site was identified as a phosphorylated target of GSK-3β. Moreover, we established two cell lines expressing either T294D (phosphor-mimic) or T294A (phosphor-deficiency) SKAP to analyze the effect of SKAP phosphorylation on EC cell invasion, migration, and epithelial-mesenchymal transition (EMT) process. GSK-3β was overexpressed and positively correlated with SKAP levels in EC tissues. Increased GSK-3β expression was associated with EC poor prognosis. Both of GSK-3β knockdown and silencing SKAP decreased EC cell migration and invasion. GSK-3β phosphorylated SKAP protein at Thr294 site. Additionally, a T294D mutant SKAP enhanced cell migration, invasion, and EMT process. Conversely, a T294A mutant SKAP inhibited EC cell malignancy. Meanwhile, cell invasion and migration abilities were inhibited after silencing GSK-3β in EC109-WT, EC109-T294A and EC109-T294D cells. Phosphorylation of SKAP induced by GSK-3β promoted EC cell migration and invasion.

Development of inhibitors targeting glycogen synthase kinase-3β for human diseases: Strategies to improve selectivity

Glycogen synthase kinase-3β (GSK-3β) is a conserved serine/threonine kinase that participates in the transmission of multiple signaling pathways and plays an important role in the occurrence and development of human diseases, such as metabolic diseases, neurological diseases and cancer, making it to be a potential and promising drug target. To date, copious GSK-3β inhibitors have been synthesized, but only few have entered clinical trials. Most of them exerts poor selectivity, concomitant off-target effects and side effects. This review summarizes the structural characteristics, biological functions and relationship with diseases of GSK-3β, as well as the selectivity profile and therapeutic potential of different categories of GSK-3β inhibitors. Strategies for increasing selectivity and reducing adverse effects are proposed for the future design of GSK-3β inhibitors.

Nobiletin Induces Ferroptosis in Human Skin Melanoma Cells Through the GSK3β-Mediated Keap1/Nrf2/HO-1 Signalling Pathway

Melanoma is an aggressive malignant skin tumour with an increasing global incidence. However, current treatments have limitations owing to the acquired tumour drug resistance. Ferroptosis is a recently discovered form of programmed cell death characterised by iron accumulation and lipid peroxidation and plays a critical role in tumour growth inhibition. Recently, ferroptosis inducers have been regarded as a promising therapeutic strategy to overcome apoptosis resistance in tumour cells. In this study, we reported that nobiletin, a natural product isolated from citrus peel, and exhibited antitumour activity by inducing ferroptosis in melanoma cells. Subsequently, we further explored the potential mechanism of nobiletin-induced ferroptosis, and found that the expression level of glycogen synthase kinase 3β (GSK3β) in the skin tissue of patients with melanoma was significantly reduced compared to that in the skin of normal tissue. Additionally, nobiletin increased GSK3β expression in melanoma cells. Moreover, the level of Kelch-like Ech-associated protein-1 (Keap1) was increased, while the level of nuclear factor erythroid 2-related factor 2 (Nrf2), and haem oxygenase-1 (HO-1) was decreased in nobiletin-treated melanoma cells, suggesting that the antioxidant defence system was downregulated. Furthermore, knockdown of GSK3β significantly reduced nobiletin-induced ferroptosis and upregulated the Keap1/Nrf2/HO-1 signalling pathway, while the opposite was observed in cells overexpressing GSK3β. In addition, molecular docking assay results indicated that nobiletin showed strong binding affinities for GSK3β, Keap1, Nrf2, and HO-1. Taken together, our results demonstrated that nobiletin could induce ferroptosis by regulating the GSK3β-mediated Keap1/Nrf2/HO-1 signalling pathway in human melanoma cells. Hence, nobiletin stands as a promising drug candidate for melanoma treatment with development prospects.

iTRAQ-Based Proteome Profiling of Differentially Expressed Proteins in Insulin-Resistant Human Hepatocellular Carcinoma

Recently, the incidences of insulin resistance (IR) and IR-related complications have increased throughout the world, which also associate with poor prognosis in hepatocellular carcinoma (HCC). Numerous studies had been focused on the role of IR in tumorigenesis and prognosis of HCC. The proteomic analysis of IR related hepatocellular carcinoma had not been reported by now. In the present study, 196 differentially expressed proteins (DEPs) were identified between insulin resistant HepG2 cells and their parental cells, of which 109 proteins were downregulated and 87 proteins were upregulated. Bioinformatics analysis indicated that these DEPs were highly enriched in process of tumorigenesis and tumor progression. PPI network analysis showed that SOX9, YAP1 and GSK3β as the key nodes, were involved in Wnt and Hippo signaling pathways. Survival analysis revealed that high expression of SOX9 and PRKD3 were strongly associated with reduced patient survival rate. parallel reaction monitoring (PRM) and Western blot analysis were applied to verify the protein level of these four key nodes mentioned above, which showed the same trend as quantified by isobaric tags for relative and absolute quantitation (iTRAQ) and confirmed the reliability of our Proteome Profiling analysis. Our results indicated that IR related dysregulation of protein expression might participated in tumorigenesis and malignant phenotype of hepatocarcinoma cells.