Dicumarol inhibits PDK1 and targets multiple malignant behaviors of ovarian cancer cells

Lactic acid metabolism: gynecological cancer's Achilles' heel

Lactic acid is significantly expressed in many cancers, including gynecological cancer, and has become a key regulator of the proliferation, development, metastasis and invasion of these cancers. In clinical and experimental studies, the level of lactic acid in gynecological cancer is closely related to metastasis and invasion, tumor recurrence and poor prognosis. Lactic acid can regulate the internal metabolic pathway of gynecological cancer cells and drive the autonomous role of non-cancer cells in gynecological cancer. In addition to being used as a source of energy metabolism by gynecological cancer cells, lactic acid can also be transported from cancer cells to neighboring cancer cells, stroma and vascular endothelial cells (ECs) to further guide metabolic reprogramming. Lactic acid is also involved in promoting inflammation and angiogenesis in gynecologic tumors. Therefore, we reviewed the mechanisms and recent advances in the production and transport of lactic acid in gynecological cancer. These advances and evidence suggest that targeted lactic acid metabolism is a promising cancer treatment.

In silico docking, ADMET profiling, and bio-accessibility experimentation on Breynia retusa phytocompounds and in vitro validation for anti-proliferative potencies against ovarian carcinoma

This study aimed to assess the medicinal properties of Breynia retusa, a plant rich in phytocompounds predominantly used as an ethnomedicinal agent in Western Ghats, which appeared to be promising for therapeutic use, especially in the treatment of ovarian cancer. Herein, its cytotoxic potential on ovarian cancer cell lines SKOV-3, neurotoxicity, antioxidant activity, and molecular docking was determined to aid in explaining the mechanisms of interactions with proteins related to ovarian cancer. B . retusa methanolic extract demonstrated exuberant antioxidant activity, with 81.91% scavenging ability of DPPH radicals and efficient reduction of phosphomolybdenum (22.98 mg ascorbic acid equivalents antioxidant capacity/g extract). The extract proved to be an important anti-inflammatory agent through membrane stabilization inhibition of 83%. The cytotoxicity study against the SKOV-3 cell line indicated an IC50 value of 34.01 µg/mL and a very negligible neurotoxicity in SH-SY5Y cell lines. The GC-MS and HPLC profiling indicated many anticancer compounds in the extract such as secalciferol, methyl gallate, ricinoleic acid, gallic acid, and naringenin. The docking study showed significant interactions of secalciferol molecules with the key ovarian cancer proteins, which include IGF1 (-6.758 kcal/mol) and c-ERBB2 (-4.281 kcal/mol). Fatty acid derivatives and methyl gallate showed efficient dock scores (< -5.0 kcal/mol) with antioxidant (catalase and superoxide dismutase) enzymes and inflammatory cytokines (IL-6 and COX-1), respectively, as evidences of antioxidant and anti-inflammatory potentials. The bio-accessibility of phenolics and their antioxidant activity ranged above 90%, indicating the promising bioavailability of phytochemicals expected in vivo. Hence the current study emphasizes the anticancer potential of B. retusa phytocompounds that appeared to interact very strongly with ovarian cancer targets and confirms the dose-dependent cytotoxic and antioxidant activities of B. retusa methanolic extract.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-025-04276-8.

Chloroquine sensitises hypoxic colorectal cancer cells to ROS-mediated cell death via structural disruption of pyruvate dehydrogenase kinase 1

Chloroquine (CQ), an autophagy antagonist, has been recently explored as a repurposable medicine for cancer; however the exact mechanism of its action is still not known. The present study investigated the effect of CQ on colorectal cancer cells to elucidate the underlying molecular mechanisms. We report for the first time that CQ suppresses hypoxia-induced growth and survival of HCT-116 cells by reducing glycolytic capacity and NAD+ production through inhibition of PDK1. Furthermore, in silico and in vitro studies revealed that CQ induces structural alteration in the PDK1 protein, leading to its destabilization and promotes its enhanced degradation by proteases. This degradation is in turn inhibited by the MG-132 protease inhibitor. Moreover, CQ-induced suppression of PDK1 results in mitochondrial damage through excessive production of ROS, as reflected by the reduction in mitochondrial membrane potential, which in turn triggers apoptosis through PARP cleavage and Caspase activation. These findings advocate CQ as a promising repurposable chemotherapeutic for colorectal cancer and a novel inhibitor of PDK1.

Incredible use of plant-derived bioactives as anticancer agents

Cancer is a major global concern. Despite considerable advancements in cancer therapy and control, there are still large gaps and requirements for development. In recent years, various naturally occurring anticancer drugs have been derived from natural resources, such as alkaloids, glycosides, terpenes, terpenoids, flavones, and polyphenols. Plant-derived substances exhibit their anticancer potential through antiproliferative activity, cytotoxicity, apoptosis, angiogenesis and cell cycle arrest. Natural compounds can affect the molecular activity of cells through various signaling pathways, like the cell cycle pathway, STAT-3 pathway, PI3K/Akt, and Ras/MAP-kinase pathways. Capsaicin, ouabain, and lycopene show their anticancer potential through the STAT-3 pathway in breast, colorectal, pancreatic, lung, cervical, ovarian and colon cancers. Epigallocatechin gallate and emodin target the JNK protein in skin, breast, and lung cancers, while berberine, evodiamine, lycorine, and astragalin exhibit anticancer activity against breast, liver, prostate, pancreatic and skin cancers and leukemia through the PI3K/Akt and Ras/MAP-kinase pathways. In vitro/in vivo investigations revealed that secondary metabolites suppress cancer cells by causing DNA damage and activating apoptosis-inducing enzymes. After a meticulous literature review, the anti-cancer potential, mode of action, and clinical trials of 144 bioactive compounds and their synthetic analogues are included in the present work, which could pave the way for using plant-derived bioactives as anticancer agents.

Glycolysis, the sweet appetite of the tumor microenvironment

Cancer cells display an altered metabolic phenotype, characterised by increased glycolysis and lactate production, even in the presence of sufficient oxygen - a phenomenon known as the Warburg effect. This metabolic reprogramming is a crucial adaptation that enables cancer cells to meet their elevated energy and biosynthetic demands. Importantly, the tumor microenvironment plays a pivotal role in shaping and sustaining this metabolic shift in cancer cells. This review explores the intricate relationship between the tumor microenvironment and the Warburg effect, highlighting how communication within this niche regulates cancer cell metabolism and impacts tumor progression and therapeutic resistance. We discuss the potential of targeting the Warburg effect as a promising therapeutic strategy, with the aim of disrupting the metabolic advantage of cancer cells and enhancing our understanding of this complex interplay within the tumor microenvironment.

A comprehensive review on the potential of coumarin and related derivatives as multi-target therapeutic agents in the management of gynecological cancers

Current treatments for gynecological cancers include surgery, radiotherapy, and chemotherapy. However, these treatments often have significant side effects. Phytochemicals, natural compounds derived from plants, offer promising anticancer properties. Coumarins, a class of benzopyrone compounds found in various plants like tonka beans, exhibit notable antitumor effects. These compounds induce cell apoptosis, target PI3K/Akt/mTOR signaling pathways, inhibit carbonic anhydrase, and disrupt microtubules. Additionally, they inhibit tumor multidrug resistance and angiogenesis and regulate reactive oxygen species. Specific coumarin derivatives, such as auraptene, praeruptorin, osthole, and scopoletin, show anti-invasive, anti-migratory, and antiproliferative activities by arresting the cell cycle and inducing apoptosis. They also inhibit metalloproteinases-2 and -9, reducing tumor cell migration, invasion, and metastasis. These compounds can sensitize tumor cells to radiotherapy and chemotherapy. Synthetic coumarin derivatives also demonstrate potent antitumor and anticancer activities with minimal side effects. Given their diverse mechanisms of action and minimal side effects, coumarin-class phytochemicals hold significant potential as therapeutic agents in gynecological cancers, potentially improving treatment outcomes and reducing side effects. This review will aid in the synthesis and development of novel coumarin-based drugs for these cancers.

Notch Signaling Suppression by Golden Phytochemicals: Potential for Cancer Therapy

Cancer is one of the main causes of mortality worldwide. Cancer cells are characterized by unregulated cellular processes, including proliferation, progression, and angiogenesis. The occurrence of these processes is due to the dysregulation of various signaling pathways such as NF-κB (nuclear factor-κB), Wnt/beta-catenin, Notch signaling and MAPK (mitogen-activated protein kinases). Notch signaling pathways cause the progression of various types of malignant tumors. Among the phytochemicals for cancer therapy, several have attracted great interest, including curcumin, genistein, quercetin, silibinin, resveratrol, cucurbitacin and glycyrrhizin. Given the great cellular and molecular heterogeneity within tumors and the high toxicity and side effects of synthetic chemotherapeutics, natural products with pleiotropic effects that simultaneously target numerous signaling pathways appear to be ideal substitutes for cancer therapy. With this in mind, we take a look at the current status, impact and potential of known compounds as golden phytochemicals on key signaling pathways in tumors, focusing on the Notch pathway. This review may be useful for discovering new molecular targets for safe and efficient cancer therapy with natural chemotherapeutics.

Transcription Factor E2F8 Activates PDK1-Mediated DNA Damage Repair to Enhance Cisplatin Resistance in Lung Adenocarcinoma

INTRODUCTION

Cisplatin (DDP) is the commonest chemo drug in lung adenocarcinoma (LUAD) treatment, and DDP resistance is a significant barrier to therapeutic therapy. This study attempted to elucidate the impact of PDK1 on DDP resistance in LUAD and its mechanism.

METHODS

Bioinformatics analysis was used to determine the expression and enriched pathways of PDK1 in LUAD tissue. Subsequently, E2F8, the upstream transcription factor of PDK1, was predicted, and the binding relationship between the two was analyzed using dual-luciferase and ChIP experiments. PDK1 and E2F8 levels in LUAD tissues and cells were detected via qRT-PCR. Cell viability, proliferation, and apoptosis levels were assayed by CCK-8, EdU, and flow cytometry experiments, respectively. Comet assay was used to assess DNA damage, and immunofluorescence was used to assess the expression of γ-H2AX. NHEJ reporter assay was to assess DNA repair efficiency. Western blot tested levels of DNA damage repair (DDR)-related proteins. Immunohistochemistry assessed the expression of relevant genes. Finally, an animal model was constructed to investigate the influence of PDK1 expression on LUAD growth.

RESULTS

PDK1 was found to be upregulated in LUAD and enhanced DDP resistance by mediating DDR. E2F8 was identified as an upstream transcription factor of PDK1 and was highly expressed in LUAD. Rescue experiments presented that knocking down E2F8 could weaken the promotion of PDK1 overexpression on DDR-mediated DDP resistance in LUAD. In vivo experiments showed that knocking down PDK1 plus DDP significantly reduced the growth of xenograft tumors.

CONCLUSION

Our results indicated that the E2F8/PDK1 axis mediated DDR to promote DDP resistance in LUAD. Our findings lead to an improved treatment strategy after drug resistance.

EIF4A3 targeted therapeutic intervention in glioblastoma multiforme using phytochemicals from Indian medicinal plants - an integration of phytotherapy into precision onco-medicine

Glioblastoma Multiforme (GBM), an aggressive brain tumor (grade-IV astrocytoma), poses treatment challenges. Poor prognosis results from the rapid growth, highlighting the role of EIF4A3 in regulating non-coding RNAs. EIF4A3 promotes the expression of several non-coding RNAs, viz, Circ matrix metallopeptidase 9 (MMP9), a prominent oncogene, by interacting with the upstream region of the circMMP9 mRNA transcript and acts on cell proliferation, migration, and invasion of GBM. However, research shows that EIF4A3 knockdown inhibits glioblastoma progression and increases apoptosis. In this study, we explored the efficiency of the phytochemicals from plants like Withania somnifera and Castanea sativa with potential anti-glioblastoma effects as obtained from the Indian Medicinal Plants, Phytochemistry and Therapeutics (IMPPAT) database. Consequently, we have performed a virtual screening of the compounds against the protein EIF4A3. We further investigated the efficiency of the shortlisted compounds based on docking scores evaluated using GOLD, AutoDock4.2, LeDock, and binding free energy analyses using Molecular Mechanics Poisson-Boltzmann Surface Area (MMPBSA). Among the phytochemicals studied so far, several Withania-specific compounds from Withania somnifera and a single dietary compound, viz., Thiamine from Castanea sativa, have exhibited comparatively good blood-brain barrier permeability, significant binding affinity towards the EIF4A3, and good ADMET properties. Furthermore, we have verified the interaction stability of the lead molecules with EIF4A3 using MD simulations. Thus, the present study offers an opportunity to develop drug candidates targeting glioblastoma caused by EIF4A3 over-expression, integrating phytotherapy into precision oncology to create tailored and precise natural treatment strategies for cancer.

Phytotherapeutics in Cancer: From Potential Drug Candidates to Clinical Translation

Annually, a significant number of individuals succumb to cancer, an anomalous cellular condition characterized by uncontrolled cellular proliferation and the emergence of highly perilous tumors. Identifying underlying molecular mechanism(s) driving disease progression has led to various inventive therapeutic approaches, many of which are presently under pre-clinical and/or clinical trials. Over the recent years, numerous alternative strategies for addressing cancer have also been proposed and put into practice. This article delineates the modern therapeutic drugs employed in cancer treatment and their associated toxicity. Due to inherent drug toxicity associated with most modern treatments, demand rises for alternative therapies and phytochemicals with minimal side effects and proven efficacy against cancer. Analogs of taxol, Vinca alkaloids like vincristine and vinblastine, and podophyllotoxin represent a few illustrative examples in this context. The phytochemicals often work by modifying the activity of molecular pathways that are thought to be involved in the onset and progression of cancer. The principal objective of this study is to provide an overview of our current understanding regarding the pharmacologic effects and molecular targets of the active compounds found in natural products for cancer treatment and collate information about the recent advancements in this realm. The authors' interest in advancing the field of phytochemical research stems from both the potential of these compounds for use as drugs as well as their scientific validity. Accordingly, the significance of herbal formulations is underscored, shedding light on anticancer phytochemicals that are sought after at both pre-clinical and clinical levels, with discussion on the opportunities and challenges in pre-clinical and clinical cancer studies.

Research progress on the mechanism of glycolysis in ovarian cancer

Glycolysis is the preferred energy metabolism pathway in cancer cells even when the oxygen content is sufficient. Through glycolysis, cancer cells convert glucose into pyruvic acid and then lactate to rapidly produce energy and promote cancer progression. Changes in glycolysis activity play a crucial role in the biosynthesis and energy requirements of cancer cells needed to maintain growth and metastasis. This review focuses on ovarian cancer and the significance of key rate-limiting enzymes (hexokinase, phosphofructokinase, and pyruvate kinase, related signaling pathways (PI3K-AKT, Wnt, MAPK, AMPK), transcription regulators (HIF-1a), and non-coding RNA in the glycolytic pathway. Understanding the relationship between glycolysis and these different mechanisms may provide new opportunities for the future treatment of ovarian cancer.

Design, synthesis and biological evaluation of novel modified dual-target shikonin derivatives for colorectal cancer treatment

Warburg effect provides energy and material essential for tumor proliferation, the reverse of Warburg effect provides insights into the development of a novel anti-cancer strategy. Pyruvate kinase 2 (PKM2) and pyruvate dehydrogenase kinase 1 (PDK1) are two key enzymes in tumor glucose metabolism pathway that not only contribute to the Warburg effect through accelerating aerobic glycolysis, but also serve as druggable target for colorectal cancer (CRC). Considering that targeting PKM2 or PDK1 alone does not seem to be sufficient to remodel abnormal glucose metabolism and achieve significant antitumor activity, a series of novel benzenesulfonyl shikonin derivatives were designed to regulate PKM2 and PDK1 simultaneously. By means of molecular docking and antiproliferative screen, we found that compound Z10 could act as the combination of PKM2 activator and PDK1 inhibitor, thereby significantly inhibited glycolysis that reshaping tumor metabolism. Moreover, Z10 could inhibit proliferation, migration and induce apoptosis in CRC cell HCT-8. Finally, the in vivo anti-tumor activity of Z10 was evaluated in a colorectal cancer cell xenograft model in nude mice and the results demonstrated that Z10 induced tumor cell apoptosis and inhibited tumor cell proliferation with lower toxicity than shikonin. Our findings indicated that it is feasible to alter tumor energy metabolism through multi-target synergies, and the dual-target benzenesulfonyl shikonin derivative Z10 could be a potential anti-CRC agent.

Growth hormone remodels the 3D-structure of the mitochondria of inflammatory macrophages and promotes metabolic reprogramming

INTRODUCTION

Macrophages are a heterogeneous population of innate immune cells that support tissue homeostasis through their involvement in tissue development and repair, and pathogen defense. Emerging data reveal that metabolism may control macrophage polarization and function and, conversely, phenotypic polarization may drive metabolic reprogramming.

METHODS

Here we use biochemical analysis, correlative cryogenic fluorescence microscopy and cryo-focused ion-beam scanning electron microscopy.

RESULTS

We demonstrate that growth hormone (GH) reprograms inflammatory GM-CSF-primed monocyte-derived macrophages (GM-MØ) by functioning as a metabolic modulator. We found that exogenous treatment of GM-MØ with recombinant human GH reduced glycolysis and lactate production to levels similar to those found in anti-inflammatory M-MØ. Moreover, GH treatment of GM-MØ augmented mitochondrial volume and altered mitochondrial dynamics, including the remodeling of the inner membrane to increase the density of cristae.

CONCLUSIONS

Our data demonstrate that GH likely serves a modulatory role in the metabolism of inflammatory macrophages and suggest that metabolic reprogramming of macrophages should be considered as a new target to intervene in inflammatory diseases.

Phenolic Acids-Mediated Regulation of Molecular Targets in Ovarian Cancer: Current Understanding and Future Perspectives

Cancer is a global health concern with a dynamic rise in occurrence and one of the leading causes of mortality worldwide. Among different types of cancer, ovarian cancer (OC) is the seventh most diagnosed malignant tumor, while among the gynecological malignancies, it ranks third after cervical and uterine cancer and sadly bears the highest mortality and worst prognosis. First-line treatments have included a variety of cytotoxic and synthetic chemotherapeutic medicines, but they have not been particularly effective in extending OC patients' lives and are associated with side effects, recurrence risk, and drug resistance. Hence, a shift from synthetic to phytochemical-based agents is gaining popularity, and researchers are looking into alternative, cost-effective, and safer chemotherapeutic strategies. Lately, studies on the effectiveness of phenolic acids in ovarian cancer have sparked the scientific community's interest because of their high bioavailability, safety profile, lesser side effects, and cost-effectiveness. Yet this is a road less explored and critically analyzed and lacks the credibility of the novel findings. Phenolic acids are a significant class of phytochemicals usually considered in the nonflavonoid category. The current review focused on the anticancer potential of phenolic acids with a special emphasis on chemoprevention and treatment of OC. We tried to summarize results from experimental, epidemiological, and clinical studies unraveling the benefits of various phenolic acids (hydroxybenzoic acid and hydroxycinnamic acid) in chemoprevention and as anticancer agents of clinical significance.

Dicoumarol: from chemistry to antitumor benefits

Dicoumarol, a coumarin-like compound, is known for its anticoagulant properties associated with the ability to inhibit vitamin K, being prescribed as a drug for several decades. The pharmaceutical value of dicoumarol turned it into a focus of chemists' attention, aiming its synthesis and of dicoumarol derivatives, bringing to light new methodologies. In recent years, several other bioactive effects have been claimed for dicoumarol and its derivatives, including anti-inflammatory, antimicrobial, antifungal, and anticancer, although the mechanisms of action underlying them are mostly not disclosed and additional research is needed to unravel them. This review presents a state of the art on the chemistry of dicoumarols, and their potential anticancer characteristics, highlighting the mechanisms of action elucidated so far. In parallel, we draw attention to the lack of in vivo studies and clinical trials to assess the safety and efficacy as drugs for later application.

Recent advances in understanding the metabolic plasticity of ovarian cancer: A systematic review

Epithelial ovarian cancer (EOC) is a gynecologic malignancy with a poor prognosis due to resistance to first-line chemotherapeutic agents. Some cancer cells are primarily dependent on glycolysis, but others favor mitochondrial oxidative phosphorylation (OXPHOS) over glycolysis. Changes in metabolic reprogramming have been reported to be involved in cancer cell survival. In this review, we summarize the metabolic profiles (e.g., metabolic heterogeneity, plasticity, and reprogramming) and adaptation to the dynamic tumor microenvironment and discuss potential novel therapeutic strategies. A literature search was performed between January 2000 and March 2022 in the PubMed and Google Scholar databases using a combination of specific terms. Ovarian cancer cells, including cancer stem cells, depend on glycolysis, OXPHOS, or both for survival. Several environmental stresses, such as nutrient starvation or glucose deprivation, hypoxic stress, acidification, and excessive reactive oxygen species (ROS) generation, reprogram the metabolic pathways to adapt. The interaction between tumors and adjacent stromal cells allows cancer cells to enhance mitochondrial energy metabolism. The metabolic reprogramming varies depending on genomic and epigenetic alterations of metabolism-related genes and the metabolic environment. Developing accurate and non-invasive methods for early identification of metabolic alterations could facilitate optimal cancer diagnosis and treatment. Cancer metabolism research has entered an exciting era where novel strategies targeting metabolic profiling will become more innovative.

Metabolic reprogramming of the tumor immune microenvironment in ovarian cancer: A novel orientation for immunotherapy

Ovarian cancer is the most lethal gynecologic tumor, with the highest mortality rate. Numerous studies have been conducted on the treatment of ovarian cancer in the hopes of improving therapeutic outcomes. Immune cells have been revealed to play a dual function in the development of ovarian cancer, acting as both tumor promoters and tumor suppressors. Increasingly, the tumor immune microenvironment (TIME) has been proposed and confirmed to play a unique role in tumor development and treatment by altering immunosuppressive and cytotoxic responses in the vicinity of tumor cells through metabolic reprogramming. Furthermore, studies of immunometabolism have provided new insights into the understanding of the TIME. Targeting or activating metabolic processes of the TIME has the potential to be an antitumor therapy modality. In this review, we summarize the composition of the TIME of ovarian cancer and its metabolic reprogramming, its relationship with drug resistance in ovarian cancer, and recent research advances in immunotherapy.

Involvement of Phytochemical-Encapsulated Nanoparticles' Interaction with Cellular Signalling in the Amelioration of Benign and Malignant Brain Tumours

Brain tumours have unresolved challenges that include delay prognosis and lower patient survival rate. The increased understanding of the molecular pathways underlying cancer progression has aided in developing various anticancer medications. Brain cancer is the most malignant and invasive type of cancer, with several subtypes. According to the WHO, they are classified as ependymal tumours, chordomas, gangliocytomas, medulloblastomas, oligodendroglial tumours, diffuse astrocytomas, and other astrocytic tumours on the basis of their heterogeneity and molecular mechanisms. The present study is based on the most recent research trends, emphasising glioblastoma cells classified as astrocytoma. Brain cancer treatment is hindered by the failure of drugs to cross the blood–brain barrier (BBB), which is highly impregnableto foreign molecule entry. Moreover, currently available medications frequently fail to cross the BBB, whereas chemotherapy and radiotherapy are too expensive to be afforded by an average incomeperson and have many associated side effects. When compared to our current understanding of molecularly targeted chemotherapeutic agents, it appears that investigating the efficacy of specific phytochemicals in cancer treatment may be beneficial. Plants and their derivatives are game changers because they are efficacious, affordable, environmentally friendly, faster, and less toxic for the treatment of benign and malignant tumours. Over the past few years, nanotechnology has made a steady progress in diagnosing and treating cancers, particularly brain tumours. This article discusses the effects of phytochemicals encapsulated in nanoparticles on molecular targets in brain tumours, along with their limitations and potential challenges.

Bax/Bcl-2 Cascade Is Regulated by the EGFR Pathway: Therapeutic Targeting of Non-Small Cell Lung Cancer

Non-small cell lung carcinoma (NSCLC) comprises 80%-85% of lung cancer cases. EGFR is involved in several cancer developments, including NSCLC. The EGFR pathway regulates the Bax/Bcl-2 cascade in NSCLC. Increasing understanding of the molecular mechanisms of fundamental tumor progression has guided the development of numerous antitumor drugs. The development and improvement of rationally planned inhibitors and agents targeting particular cellular and biological pathways in cancer have been signified as a most important paradigm shift in the strategy to treat and manage lung cancer. Newer approaches and novel chemotherapeutic agents are required to accompany present cancer therapies for improving efficiency. Using natural products as a drug with an effective delivery system may benefit therapeutics. Naturally originated compounds such as phytochemicals provide crucial sources for novel agents/drugs and resources for tumor therapy. Applying the small-molecule inhibitors (SMIs)/phytochemicals has led to potent preclinical discoveries in various human tumor preclinical models, including lung cancer. In this review, we summarize recent information on the molecular mechanisms of the Bax/Bcl-2 cascade and EGFR pathway in NSCLC and target them for therapeutic implications. We further described the therapeutic potential of Bax/Bcl-2/EGFR SMIs, mainly those with more potent and selectivity, including gefitinib, EGCG, ABT-737, thymoquinone, quercetin, and venetoclax. In addition, we explained the targeting EGFR pathway and ongoing in vitro and in vivo and clinical investigations in NSCLC. Exploration of such inhibitors facilitates the future treatment and management of NSCLC.

Ten-gene signature reveals the significance of clinical prognosis and immuno-correlation of osteosarcoma and study on novel skeleton inhibitors regarding MMP9

OBJECTIVES

This study aimed to identify novel targets in the carcinogenesis, therapy and prognosis of osteosarcoma from genomic level, together with screening ideal lead compounds with potential inhibition regarding MMP-9.

METHODS

Gene expression profiles from GSE12865, GSE14359, GSE33382, GSE36001 and GSE99671 were obtained respectively from GEO database. Differentially expressed genes were identified, and functional enrichment analysis, such as GO, KEGG, GSEA, PPI were performed to make a comprehensive understanding of the hub genes. Next, a series of high-precision computational techniques were conducted to screen potential lead compounds targeting MMP9, including virtual screening, ADME, toxicity prediction, and accurate docking analysis.

RESULTS

10 genes, MMP9, CD74, SPP1, CXCL12, TYROBP, FCER1G, HCLS1, ARHGDIB, LAPTM5 and IGF1R were identified as hub genes in the initiation of osteosarcoma. Machine learning, multivariate Cox analysis, ssGSEA and survival analysis demonstrated that these genes had values in prognosis, immune-correlation and targeted treatment. Tow novel compounds, ZINC000072131515 and ZINC000004228235, were screened as potential inhibitor regarding MMP9, and they could bind to MMP9 with favorable interaction energy and high binding affinity. Meanwhile, they were precited to be efficient and safe drugs with low-ames mutagenicity, none weight evidence of carcinogenicity, as well as non-toxic with liver.

CONCLUSIONS

This study revealed the significance of 10-gene signature in the development of osteosarcoma. Besides, drug candidates identified in this study provided a solid basis on MMP9 inhibitors' development.

α-Lipoic Acid Targeting PDK1/NRF2 Axis Contributes to the Apoptosis Effect of Lung Cancer Cells

As an antioxidant, α-lipoic acid (LA) has attracted much attention to cancer research. However, the exact mechanism of LA in cancer progression control and prevention remains to be unclear. In this study, we demonstrated that α-lipoic acid has inhibitory effects on the proliferation, migration, and proapoptotic effects of non-small-cell lung cancer (NSCLC) cell lines A549 and PC9. LA-induced NSCLC cell apoptosis was mediated by elevated mitochondrial reactive oxygen species (ROS). Further study confirmed that it is by downregulating the expression of PDK1 (the PDH kinase), resulted in less phospho-PDH phenotype which could interact with Keap1, the negative controller of NRF2, directly leading to NRF2 decrease. Thus, by downregulating the NRF2 antioxidant system, LA plays a role in promoting apoptosis through the ROS signaling pathway. Moreover, LA could enhance other PDK inhibitors with the proapoptosis effect. In summary, our study shows that LA promotes apoptosis and exerts its antitumor activity against lung cancer by regulating mitochondrial energy metabolism enzyme-related antioxidative stress system. Administration of LA to the tumor-bearing animal model further supported the antitumor effect of LA. These findings provided new ideas for the clinical application of LA in the field of cancer therapy.

Targeting pyruvate dehydrogenase kinase signaling in the development of effective cancer therapy

Pyruvate is irreversibly decarboxylated to acetyl coenzyme A by mitochondrial pyruvate dehydrogenase complex (PDC). Decarboxylation of pyruvate is considered a crucial step in cell metabolism and energetics. The cancer cells prefer aerobic glycolysis rather than mitochondrial oxidation of pyruvate. This attribute of cancer cells allows them to sustain under indefinite proliferation and growth. Pyruvate dehydrogenase kinases (PDKs) play critical roles in many diseases because they regulate PDC activity. Recent findings suggest an altered metabolism of cancer cells is associated with impaired mitochondrial function due to PDC inhibition. PDKs inhibit the PDC activity via phosphorylation of the E1a subunit and subsequently cause a glycolytic shift. Thus, inhibition of PDK is an attractive strategy in anticancer therapy. This review highlights that PDC/PDK axis could be implicated in cancer's therapeutic management by developing potential small-molecule PDK inhibitors. In recent years, a dramatic increase in the targeting of the PDC/PDK axis for cancer treatment gained an attention from the scientific community. We further discuss breakthrough findings in the PDC-PDK axis. In addition, structural features, functional significance, mechanism of activation, involvement in various human pathologies, and expression of different forms of PDKs (PDK1-4) in different types of cancers are discussed in detail. We further emphasized the gene expression profiling of PDKs in cancer patients to prognosis and therapeutic manifestations. Additionally, inhibition of the PDK/PDC axis by small molecule inhibitors and natural compounds at different clinical evaluation stages has also been discussed comprehensively.

Pyruvate dehydrogenase kinases (PDKs): an overview toward clinical applications

Pyruvate dehydrogenase kinase (PDK) can regulate the catalytic activity of pyruvate decarboxylation oxidation via the mitochondrial pyruvate dehydrogenase complex, and it further links glycolysis with the tricarboxylic acid cycle and ATP generation. This review seeks to elucidate the regulation of PDK activity in different species, mainly mammals, and the role of PDK inhibitors in preventing increased blood glucose, reducing injury caused by myocardial ischemia, and inducing apoptosis of tumor cells. Regulations of PDKs expression or activity represent a very promising approach for treatment of metabolic diseases including diabetes, heart failure, and cancer. The future research and development could be more focused on the biochemical understanding of the diseases, which would help understand the cellular energy metabolism and its regulation by pharmacological effectors of PDKs.

The IL-33/ST2 axis affects tumor growth by regulating mitophagy in macrophages and reprogramming their polarization

Objective:

Macrophages are a major component of the tumor microenvironment. M1 macrophages secrete pro-inflammatory factors that inhibit tumor growth and development, whereas tumor-associated macrophages (TAMs) mainly exhibit an M2 phenotype. Our previous studies have shown that the interleukin-33/ST2 (IL-33/ST2) axis is essential for activation of the M1 phenotype. This study investigates the role of the IL-33/ST2 axis in TAMs, its effects on tumor growth, and whether it participates in the mutual conversion between the M1 and M2 phenotypes.

Methods:

Bone marrow-derived macrophages were extracted from wildtype, ST2 knockout (ST2^−/−), and Il33-overexpressing mice and differentiated with IL-4. The mitochondrial and lysosomal number and location, and the expression of related proteins were used to analyze mitophagy. Oxygen consumption rates and glucose and lactate levels were measured to reveal metabolic changes.

Results:

The IL-33/ST2 axis was demonstrated to play an important role in the metabolic conversion of macrophages from OXPHOS to glycolysis by altering mitophagy levels. The IL-33/ST2 axis promoted enhanced cell oxidative phosphorylation, thereby further increasing M2 polarization gene expression and ultimately promoting tumor growth (P < 0.05) (Figure 4). This metabolic shift was not due to mitochondrial damage, because the mitochondrial membrane potential was not significantly altered by IL-4 stimulation or ST2 knockout; however, it might be associated with the mTOR activity.

Conclusions:

These results clarify the interaction between the IL-33/ST2 pathway and macrophage polarization, and may pave the way to the development of new cancer immunotherapies targeting the IL-33/ST2 axis.

The oncogenic and prognostic role of PDK1 in the progression and metastasis of ovarian cancer

Ovarian cancer (OC) is the most lethal of gynecological tumors in women. Tumor metabolism has become a new opportunity in the treatment of tumors. Pyruvate dehydrogenase kinase 1 (PDK1), as a key regulatory enzyme implicated in metabolic reprogramming of tumors, abnormally high expressed in various tumors and involved in the regulation of tumor cell biological behavior. However, the role of PDK1 in the occurrence and development of ovarian cancer remains unclear. Our team identified the expression of PDK1 in ovarian cancer cell lines and tissues through RT-PCR and immunohistochemical staining and evaluated the correlation of PDK1 expression with clinicopathologic features of patients and survival analyses. We used a variety of in vitro experiments to explore the influence of PDK1 on proliferation, invasion, migration, colony formation, apoptosis and the cell cycle of ovarian cancer cell lines CAOV3 and SKOV3. PDK1 was highly expressed in ovarian cancer cell lines and OC tissues. High expression of PDK1 was closely correlated to tumor size, FIGO stage, extraovarian metastases status and distribution. Univariate and multivariate Cox regression analysis identified that PDK1 was an independent prognostic factor for overall survival. Moreover, PDK1 was a superior predictor in prognosis of ovarian cancer and the incorporation of CA125 into PDK1 generated a predictive combination that displayed better predictive accuracy for overall survival. Downregulation of PDK1 suppressed the biological behavior of ovarian cancer cells due to S phase arrest and cellular apoptosis. PDK1 may serve as a novel prognostic biomarker, even a promising antineoplastic target of ovarian cancer.

Identifying Potential Biomarkers in Colorectal Cancer and Developing Non-invasive Diagnostic Models Using Bioinformatics Approaches

Background: Colorectal cancer (CRC) is one of the most frequent causes of gastrointestinal tumors. Due to the invasiveness of the current diagnostic methods, there is an urgent need to develop non-invasive diagnostic approaches for CRC. The exact mechanisms and the most important genes associated with the development of CRC are not fully demonstrated. Objectives: This study aimed to identify differentially expressed miRNAs (DEMs), key genes, and their regulators associated with the pathogenesis of CRC. The signaling pathways and biological processes (BPs) that were significantly affected in CRC were also indicated. Moreover, two non-invasive models were constructed for CRC diagnosis. Methods: The miRNA dataset GSE59856 was downloaded from the Gene Expression Omnibus (GEO) database and analyzed to identify DEMs in CRC patients compared with healthy controls (HCs). A protein-protein interaction (PPI) network was built and analyzed. Significant clusters in the PPI networks were identified, and the BPs and pathways associated with these clusters were studied. The hub genes in the PPI network, as well as their regulators were identified. Results: A total of 569 DEMs were demonstrated with the criteria of P value <0.001. A total of 110 essential genes and 30 modules were identified in the PPI network. Functional analysis revealed that 1005 BPs, 9 molecular functions (MFs), 14 cellular components (CCs), and 887 pathways were significantly affected in CRC. A total of 22 transcription factors (TFs) were demonstrated as the regulators of the hubs. Conclusion: Our results may provide new insight into the pathogenesis of CRC and advance the diagnostic and therapeutic methods of the disease. However, confirmation is required in the future.

Potential Treatment of Breast and Lung Cancer Using Dicoma anomala, an African Medicinal Plant

Globally, cancer has been identified as one of the leading causes of death in public health. Its etiology is based on consistent exposure to carcinogenic. Plant-derived anticancer compounds are known to be less toxic to the normal cells and are classified into acetylenic compounds, phenolics, terpenes, and phytosterols. Dicoma anomala is a perennial herb belonging to the family Asteraceae and is widely distributed in Sub-Saharan Africa and used in the treatment of cancer, malaria, fever, diabetes, ulcers, cold, and cough. This review aimed at highlighting the benefits of D. anomala in various therapeutic applications with special reference to the treatment of cancers and the mechanisms through which the plant-derived agents induce cell death.

Inhibition of pyruvate dehydrogenase kinase‑1 by dicoumarol enhances the sensitivity of hepatocellular carcinoma cells to oxaliplatin via metabolic reprogramming

The Warburg effect is a unique metabolic feature of the majority of tumor cells and is closely related to chemotherapeutic resistance. Pyruvate dehydrogenase kinase 1 (PDK1) is considered a 'switch' that controls the fate of pyruvate in glucose metabolism. However, to date, to the best of our knowledge, there are only a few studies to available which had studied the reduction of chemotherapeutic resistance via the metabolic reprogramming of tumor cells with PDK1 as a target. In the present study, it was found dicoumarol (DIC) reduced the phosphorylation of pyruvate dehydrogenase (PDH) by inhibiting the activity of PDK1, which converted the metabolism of human hepatocellular carcinoma (HCC) cells to oxidative phosphorylation, leading to an increase in mitochondrial reactive oxygen species ROS (mtROS) and a decrease in mitochondrial membrane potential (MMP), thereby increasing the apoptosis induced by oxaliplatin (OXA). Furthermore, the present study elucidated that the targeting of PDK1 may be a potential strategy for targeting metabolism in the chemotherapy of HCC. In addition, DIC as an 'old drug' exhibits novel efficacy, bringing new hope for antitumor therapy.

Association of the Epithelial-Mesenchymal Transition (EMT) with Cisplatin Resistance

Therapy resistance is a characteristic of cancer cells that significantly reduces the effectiveness of drugs. Despite the popularity of cisplatin (CP) as a chemotherapeutic agent, which is widely used in the treatment of various types of cancer, resistance of cancer cells to CP chemotherapy has been extensively observed. Among various reported mechanism(s), the epithelial-mesenchymal transition (EMT) process can significantly contribute to chemoresistance by converting the motionless epithelial cells into mobile mesenchymal cells and altering cell-cell adhesion as well as the cellular extracellular matrix, leading to invasion of tumor cells. By analyzing the impact of the different molecular pathways such as microRNAs, long non-coding RNAs, nuclear factor-κB (NF-ĸB), phosphoinositide 3-kinase-related protein kinase (PI3K)/Akt, mammalian target rapamycin (mTOR), and Wnt, which play an important role in resistance exhibited to CP therapy, we first give an introduction about the EMT mechanism and its role in drug resistance. We then focus specifically on the molecular pathways involved in drug resistance and the pharmacological strategies that can be used to mitigate this resistance. Overall, we highlight the various targeted signaling pathways that could be considered in future studies to pave the way for the inhibition of EMT-mediated resistance displayed by tumor cells in response to CP exposure.

Toxicokinetics of Brominated Azo Dyes in the Early Life Stages of Zebrafish (Danio rerio) Is Prone to Aromatic Substituent Changes

Brominated azo dyes (BADs) have been identified as predominant indoor brominated pollutants in daycare dust; thus, their potential health risk to children is of concern. However, the toxicities of BADs remain elusive. In this study, the toxicokinetics of two predominant BADs, Disperse Blue 373 (DB373) and Disperse Violet 93 (DV93), and their suspect metabolite 2-bromo-4,6-dinitroaniline (BDNA) was investigated in embryos of zebrafish (Danio rerio). The bioconcentration factor of DV93 at 120 hpf is 6.2-fold lower than that of DB373. The nontarget analysis revealed distinct metabolism routes between DB373 and DV93 by reducing nitro groups to nitroso (DB373) or amine (DV93), despite their similar structures. NAD(P)H quinone oxidoreductase 1 (NQO1) and pyruvate dehydrogenase were predicted as the enzymes responsible for the reduction of DB373 and DV93 by correlating time courses of the metabolites and enzyme development. Further in vitro recombinant enzyme and in vivo inhibition results validated NQO1 as the enzyme specifically reducing DB373, but not DV93. Global proteome profiling revealed that the expression levels of proteins from the "apoptosis-induced DNA fragmentation" pathway were significantly upregulated by all three BADs, supporting the bioactivation of BADs to mutagenic aromatic amines. This study discovered the bioactivation of BADs via distinct eukaryotic enzymes, implying their potential health risks.

PDK1 promotes ovarian cancer metastasis by modulating tumor-mesothelial adhesion, invasion, and angiogenesis via α5β1 integrin and JNK/IL-8 signaling

Ovarian cancer is the most lethal gynecological malignancies owing to the lack of definitive symptoms until development of widespread metastases. Identification of novel prognostic and therapeutic targets is therefore an urgent need to improve survival. Here, we demonstrated high expression of the mitochondrial gatekeeping enzyme, pyruvate dehydrogenase kinase 1 (PDK1), in both clinical samples and cell lines of ovarian cancer. PDK1 expression was significantly associated with metastasis, reduced chemosensitivity, and poor overall and disease-free survival, and further highlighted as an independent prognostic factor. Silencing of PDK1 retarded lactate production, ovarian cancer cell adhesion, migration, invasion, and angiogenesis, and consequently metastasis, concomitant with decreased α5β1 integrin expression. Phospho-kinase array profiling and RNA sequencing analyses further revealed reduction of JNK activation and IL-8 expression in PDK1-depleted cells. Conversely, PDK1 overexpression promoted cell adhesion via modulation of α5β1 integrins, along with cell migration, invasion, and angiogenesis through activation of JNK/IL-8 signaling. PDK1 depletion additionally hindered tumor growth and dissemination in nude mice in vivo. Importantly, PDK1 levels were upregulated upon treatment with conditioned medium from omental tissues, which in turn promoted metastasis. Our findings suggest that PDK1, which is regulated by the tumor microenvironment, controls lactate production and promotes ovarian cancer cell metastasis via modulation of α5β1 integrin and JNK/IL-8 signaling. To our knowledge, this is the first report to demonstrate an association between PDK1 and survival in patients with ovarian cancer, supporting its efficacy as a valuable prognostic marker and therapeutic molecular target for the disease.

Phytochemicals in Cancer Treatment: From Preclinical Studies to Clinical Practice

Cancer is a severe health problem that continues to be a leading cause of death worldwide. Increasing knowledge of the molecular mechanisms underlying cancer progression has led to the development of a vast number of anticancer drugs. However, the use of chemically synthesized drugs has not significantly improved the overall survival rate over the past few decades. As a result, new strategies and novel chemoprevention agents are needed to complement current cancer therapies to improve efficiency. Naturally occurring compounds from plants known as phytochemicals, serve as vital resources for novel drugs and are also sources for cancer therapy. Some typical examples include taxol analogs, vinca alkaloids such as vincristine, vinblastine, and podophyllotoxin analogs. These phytochemicals often act via regulating molecular pathways which are implicated in growth and progression of cancer. The specific mechanisms include increasing antioxidant status, carcinogen inactivation, inhibiting proliferation, induction of cell cycle arrest and apoptosis; and regulation of the immune system. The primary objective of this review is to describe what we know to date of the active compounds in the natural products, along with their pharmacologic action and molecular or specific targets. Recent trends and gaps in phytochemical based anticancer drug discovery are also explored. The authors wish to expand the phytochemical research area not only for their scientific soundness but also for their potential druggability. Hence, the emphasis is given to information about anticancer phytochemicals which are evaluated at preclinical and clinical level.

Pyrrole derivatives as potential anti-cancer therapeutics: synthesis, mechanisms of action, safety

Pyrrole derivatives (PDs) chloro-1-(4-chlorobenzyl)-4-((3-(trifluoromethyl)phenyl)amino)-1H-pyrrole-2,5-dione (MI-1) and 5-amino-4-(1,3-benzothyazol-2-yn)-1-(3-methoxyphenyl)-1,2-dihydro-3H-pyrrole-3-one (D1) were synthesised as inhibitors of several protein kinases including EGFR and VEGFR. The aim of the study was to reveal the exact mechanisms of PDs' action EGFR and VEGFR are involved in. We observed, that both PDs could bind with EGFR and VEGFR and form stable complexes. PDs entered into electrostatic interactions with polar groups of phospholipid heads in cell membrane, and the power of interaction depended on the nature of PD radical substituents (greater for MI-1 and smaller for D1). Partial intercalation of MI-1 into the membrane hydrophobic zone also occurred. PDs concentrations induced apoptosis in malignant cells but normal ones had different sensitivity to those. MI-1 and D1 acted like antioxidants in inflamed colonic tissue, as evidenced by reduce of lipid and protein peroxidation products (by 43-67%) and increase of superoxide dismutase activity (by 40 and 58%) with restoring these values to control ones. MI-1 restored reduced haemoglobin and normalised elevated platelets and monocytes in settings of colorectal cancer, whereas D1 normalised only platelets. Thus, MI-1 and D1 could be used as competitive inhibitors of EGFR and VEGFR and antioxidants, which might contribute to realisation of their anti-inflammatory, proapoptotic and antitumor activity.

Understanding and Targeting Apoptotic Pathways in Ovarian Cancer

Ovarian cancer cells evade the immune system as well as chemotherapeutic and/or biologic treatments through inherent or acquired mechanisms of survival and drug resistance. Depending on the cell type and the stimuli, this threshold can range from external forces such as blunt trauma to programmed processes such as apoptosis, autophagy, or necroptosis. This review focuses on apoptosis, which is one form of programmed cell death. It highlights the multiple signaling pathways that promote or inhibit apoptosis and reviews current clinical therapies that target apoptotic pathways in ovarian cancer.

Anticancer SAR establishment and novel accruing signal transduction model of drug action using biscoumarin scaffold

In this paper, we have established methylenebis (4-hydroxy-2H-chromen-2-one) as a promising anticancer scaffold with kinesin spindle protein (KSP) inhibitory activity under malignant condition. A series of biscoumarin derivatives (MN1 to MN30) with different substituent were synthesized, and their anticancer activity was explored. Six biscoumarin derivatives that were found active were further selected to formulate organic nanoparticles (ONPs). Anticancer activity of both the forms (viz conventional and ONPs) was compared. MN30 was found most potent whereby MN10 showed good anticancer activity in both, i.e., conventional and ONP form; the structural activity relationship (SAR) study has been established. Computational investigation revealed biscoumarin scaffold as a suitable pharmacophore to bind against KSP protein. Molecular dynamics simulation studies revealed protein-ligand stability and dynamic behavior of biscoumarin-KSP complex. Finally, accruing signal transduction model was formulated to explain the observed MTT trend of conventional and ONP form. The model seems useful towards solving population specific varied results of chemotherapeutic agents. According to the model, MN10 and MN30 derivatives have good pharmacodynamics inertia and therefore, both the molecules were able to provide dose-dependent cytotoxic results.

The double inhibition of PDK1 and STAT3-Y705 prevents liver metastasis in colorectal cancer

As a key glycolysis enzyme, the significance of pyruvate dehydrogenase kinase 1 (PDK1) in the development of colorectal cancer (CRC) remains unknown. This study revealed that the prognosis of CRC patients with high levels of PDK1 was poor, and PDK1 knockdown significantly reduced liver metastasis of CRC in both nude mice and immune competent BALB/C mice. When combined with cryptotanshinone (CPT), an inhibitor of STAT3-p-Y705, the liver metastasis was further inhibited. PDK1 knockdown obviously increased reactive oxygen species level in anoikis conditions and subsequently resulted in an elevated anoikis, but the combination of PDK1 knockdown and CPT showed a reduced effect on anoikis. Based on this discrepancy, the adherence ability of CRC cells to matrix protein fibronectin was further detected. It showed that PDK1 knockdown significantly decreased the adherence of CRC cells to fibronectin when combined with CPT. These results suggest that inhibition of PDK1 can decrease the surviving CRC cells in blood circulation via up-regulation of anoikis, and inhibition of STAT3-p-Y705 can prevent it to settle down on the liver premetastatic niche, which ultimately reduces liver metastasis.

Polyphyllin I induces autophagy and cell cycle arrest via inhibiting PDK1/Akt/mTOR signal and downregulating cyclin B1 in human gastric carcinoma HGC-27 cells

Paris polyphylla. is a traditional medicinal herb that has long been used to prevent cancer in many Asian countries. Polyphyllin I (PPI), an important bioactive constituent of Paris polyphylla, has been found to exhibit a wide variety of anticancer activities in many types of cancer cells. However, the effects of PPI on human gastric carcinoma cells and its mechanism of action remain unclear. In this study, we examined the effective anti-gastric carcinoma activity of PPI and its underlying mechanism of action in HGC-27 cells. In vitro, sub-micromolar concentrations of PPI inhibited HGC-27 cell proliferation with an IC₅₀ of 0.34 ± 0.06 μM after a 72-h treatment. In vivo, 3 mg/kg PPI significantly inhibited proliferation of HGC-27 tumor cells, with a 78.8% inhibition rate compared to paclitaxel, and demonstrated higher safety. Analysis of MDC and mGFP-LC3 fluorescence, Western blotting and flow cytometry indicated that PPI induced cell cycle arrest in HGC-27 cells by promoting the conversion of LC3-I to LC3-II and by downregulating cyclin B1. Furthermore, Western blotting showed that PPI inhibited the autophagy-regulating PDK1/Akt/mTOR signaling pathway in vitro and in vivo. In addition, immunohistochemistry and TUNEL staining revealed that PPI decreased Ki67 expression and increased the percentage of apoptotic cells in HGC-27 xenograft tumors. These data indicate that PPI is an PDK1/Akt/mTOR signaling inhibitor and of therapeutic relevance for gastric cancer treatment and that the rhizome of Paris polyphylla deserves further clinical investigation as an alternative therapy for gastric cancer.

Deficiency in IL-33/ST2 Axis Reshapes Mitochondrial Metabolism in Lipopolysaccharide-Stimulated Macrophages

The polarization and function of macrophages play essential roles in controlling immune responses. Interleukin (IL)-33 is a member of the IL-1 family that has been shown to influence macrophage activation and polarization, but the underlying mechanisms are not fully understood. Mitochondrial metabolism has been reported to be a central player in shaping macrophage polarization; previous studies have shown that both aerobic glycolysis and oxidative phosphorylation uniquely regulate the functions of M1 and M2 macrophages. Whether IL-33 polarizes macrophages by reshaping mitochondrial metabolism requires further investigation. In this work, we examined the mitochondrial metabolism of bone marrow-derived macrophages (BMDMs) from either wild type (WT), Il33-overexpressing, or IL-33 receptor knockout (St2^−/−) mice challenged with lipopolysaccharide (LPS). We found that after LPS stimulation, compared with WT BMDMs, St2^−/− BMDMs had reduced cytokine production and increased numbers and activity of mitochondria via the metabolism regulator peroxisome proliferator-activated receptor-C coactivator-1 α (PGC1α). This was demonstrated by increased mitochondrial DNA copy number, mitochondria counts, mitochondria fission- and fusion-related gene expression, oxygen consumption rates, and ATP production, and decreased glucose uptake, lactate production, and extracellular acidification rates. For Il33-overexpressing BMDMs, the metabolic reprogramming upon LPS stimulation was similar to WT BMDMs, and was accompanied by increased M1 macrophage activity. Our findings suggested that the pleiotropic IL-33/ST2 pathway may influence the polarization and function of macrophages by regulating mitochondrial metabolism.

Chemoresistance in ovarian cancer: exploiting cancer stem cell metabolism

Ovarian cancer is most deadly gynecologic malignancies worldwide. Chemotherapy is the mainstay treatment for ovarian cancer. Despite the initial response is promising, frequent recurrence in patients with advanced diseases remains a therapeutic challenge. Thus, understanding the biology of chemoresistance is of great importance to overcome this challenge and will conceivably benefit the survival of ovarian cancer patients. Although mechanisms underlying the development of chemoresistance are still ambiguous, accumulating evidence has supported an integral role of cancer stem cells (CSCs) in recurrence following chemotherapy. Recently, tumor metabolism has gained interest as a reason of chemoresistance in tumors and chemotherapeutic drugs in combination with metabolism targeting approaches has been found promising in overcoming therapeutic resistance. In this review, we will summarize recent studies on CSCs and metabolism in ovarian cancer and discuss possible role of CSCs metabolism in chemoresistance.

Warburg effect in Gynecologic cancers

Mammalian cells produce energy by oxidative phosphorylation under aerobic conditions. However, in the 1920s, Otto Warburg reported the so-called "Warburg effect" in which cancer cells produce ATP that is biased toward glycolysis rather than mitochondrial oxidative phosphorylation not only in anaerobic environment but also in aerobic environment. Glucose is converted into lactate without going into mitochondria after being metabolized in glycolysis. Compared with oxidative phosphorylation, the glycolysis has a faster ATP production rate but it is very inefficient, resulting in cancer cells consuming a large amount of glucose. Increased glucose metabolism has become a biomarker for cancer cells and has led to the development of positron emission tomography with fluorodeoxyglucose. Till date, the Warburg effect has been an inefficient system for cancer cells with regard to efficient energy production, but since the consumption of oxygen can be suppressed as the tumor grows in mass, it is thought that the Warburg effect is advantageous in this situation wherein the tumor can increase despite the lack of vessels. In addition, an increased lactate by the glycolysis causes acidosis in the microenvironment of tissues, which is thought to damage the surrounding normal tissues and favor the invasion and metastasis of cancer. Thus, Warburg effect is one of the key mechanisms for cancer development and will be the next promising target. In this review, we introduce key players that can be targeted in the Warburg effect and outline the prospects of treatment, targeting the Warburg effect in gynecological cancer.

SPARCL1 suppresses the proliferation and migration of human ovarian cancer cells via the MEK/ERK signaling

Ovarian cancer is the most lethal gynecological malignancy worldwide and is one of the five leading causes of cancer-associated mortality in women. There is an urgent requirement to obtain a greater understanding of the molecular mechanism underlying ovarian cancer progression in order to identify novel drug targets and biomarkers. Secreted protein acidic and rich in cysteine-like protein 1 (SPARCL1) has been suggested as a candidate tumor suppressor in various types of human cancers. However, the potential role of SPARCL1 for ovarian cancer has not yet been clearly established. In the present study, lower protein expression levels of SPARCL1 were detected in ovarian cancer tissues when compared with adjacent normal tissues. Overexpression of SPARCL1 significantly suppressed the proliferation and migration of cells from the ovarian cancer cell line SKOV-3, whereas knockdown of SPARCL1 significantly increased cell growth and migration. Furthermore, the results revealed that SPARCL1 overexpression significantly suppressed the activation of the mitogen-activated protein kinase kinase (MEK)/extracellular signal-related kinase (ERK) signaling pathway. Collectively, these results indicated that SPARCL1 may suppress the proliferation and migration of ovarian cancer cells by downregulating signaling via the MEK/ERK pathway.

A small compound spindlactone A sensitizes human endometrial cancer cells to TRAIL-induced apoptosis via the inhibition of NAD(P)H dehydrogenase quinone 1

Introduction

Spindlactone A (SPL-A) is a novel small molecule inhibitor of TACC3 that selectively inhibits the nucleation of centrosome microtubules and induces mitotic arrest in ovarian cancer cells. SPL-A is derived from dicoumarol which inhibits the activity of NAD(P)H dehydrogenase quinone oxidoreductase 1 (NQO1). This study aimed to investigate the mechanism by which SPL-A enhances TRAIL-induced apoptosis in endometrial carcinoma cells.

Materials and methods

Endometrial carcinoma cells were treated with SPL-A and/or TRAIL, and the apoptosis and protein expression in the treated cells were examined.

Results

Combined treatment with SPL-A and TRAIL significantly induced apoptosis in various human endometrial carcinoma cells, but not in normal human endometrial stromal cells and endometrial epithelial cells. Notably, both NQO1 inhibitor ES936 and NQO1 siRNA enhanced TRAIL-induced apoptosis of endometrial carcinoma cells. Furthermore, SPL-A downregulated the expression of c-FLIP, Bcl-2, Bcl-xl, and Mcl-1, while increasing p53 expression.

Conclusion

In particular, luciferase assay showed that SPL-A inhibited Bcl-2 promoter activity, and p53 inhibitor PFT-α could reverse the effect of SPL-A on Bcl-2 expression. Moreover, Bcl-2 overexpression inhibited the apoptosis induced by SPL-A and TRAIL. Taken together, our results suggest that SPL-A sensitizes endometrial cancer cells to TRAIL-induced apoptosis via the regulation of apoptosis-related proteins and the inhibition of NQO1 activity.