Shikonin, vitamin K3 and vitamin K5 inhibit multiple glycolytic enzymes in MCF-7 cells

Siah2 inhibitor and the metabolic antagonist Oxamate retard colon cancer progression and downregulate PD1 expression

BACKGROUND

Solid tumors such as colon cancer are characterized by rapid and sustained cell proliferation, which ultimately results in hypoxia, induction of hypoxia-inducible factor-1α (HIF-1α), and activation of glycolysis to promote tumor survival and immune evasion. We hypothesized that a combinatorial approach of menadione (MEN) as an indirect HIF-1α inhibitor and sodium oxamate (OX) as a glycolysis inhibitor may be a promising treatment strategy for colon cancer.

OBJECTIVES

We investigated the potential efficacy of this combination for promoting an antitumor immune response and suppressing tumor growth in a rat model of colon cancer.

METHODS

Colon cancer was induced by once-weekly subcutaneous injection of 20 mg/kg dimethylhydrazine (DMH) for 16 weeks. Control rats received the vehicle and then no further treatment (negative control) or MEN plus OX for 4 weeks (drug control). Dimethylhydrazine-treated rats were then randomly allocated to four groups: DMH alone group and other groups treated with MEN, OX, and a combination of (MEN and OX) for 4 weeks. Serum samples were assayed for the tumor marker carbohydrate antigen (CA19.9), while expression levels of HIF-1α, caspase-3, PHD3, LDH, and PD1 were evaluated in colon tissue samples by immunoassay and qRT-PCR. Additionally, Ki-67 and Siah2 expression levels were examined by immunohistochemistry.

RESULTS

The combination of MEN plus OX demonstrated a greater inhibitory effect on the expression levels of HIF-1α, Siah2, LDH, Ki-67, and PD1, and greater enhancement of caspase-3 and PHD3 expression in colon cancer tissues than either drug alone.

CONCLUSION

Simultaneous targeting of hypoxia and glycolysis pathways by a combination of MEN and OX could be a promising therapy for inhibiting colon cancer cell growth and promoting antitumor immunity [1].

Anti-cancer Research on Arnebiae Radix-derived Naphthoquinone in Recent Five Years

BACKGROUND

In recent years, many naphthoquinone compounds with anticancer activity have been identified in Arnebiae Radix, and some of them have the potential to be developed into anticancer drugs.

OBJECTIVE

This article aimed to provide a comprehensive overview of the anticancer effects of naphthoquinone compounds through a detailed review of literature and Chinese patents, and discuss their potential to be developed as anticancer drugs for clinical application.

METHODS

Research papers were collected through the databases of PubMed, Cnki and SciDirect using keyword searches "naphthoquinone compounds" and "anticancer". The keywords of "shikonin" and "shikonin derivatives" were also used in PubMed, Cnki and SciDirect databases to collect research articles. The Chinese patents were collected using the Cnki patent database.

RESULTS

Naphthoquinone compounds have been found to possess anti-cancer activity, and their modes of action are associated with inducing apoptosis, inhibiting cancer cell proliferation, promoting autophagy in cancer cells, anti-cancer angiogenesis and inhibition of cell adhesion, invasion and metastasis, inhibiting glycolysis and inhibiting DNA topoisomerase activity.

CONCLUSION

Most of the naphthoquinone compounds show effective anti-cancer activity in vitro. The structure modification of naphthoquinone aims to develop anti-cancer drugs with high efficacy and low toxicity.

Identification of potential core genes and pathways predicting pathogenesis in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is the most common subtype of head and neck cancer; however, its pathogenesis and potential therapeutic targets remain largely unknown. In the present study, we analyzed three gene expression profiles and screened differentially expressed genes (DEGs) between HNSCC and normal tissues. The DEGs were subjected to gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), protein–protein interaction (PPI), and survival analyses, while the connectivity map (CMap) database was used to predict candidate small molecules that may reverse the biological state of HNSCC. Finally, we measured the expression of the most relevant core gene in vitro and examined the effect of the top predicted potential drug against the proliferation of HNSCC cell lines. Among the 208 DEGs and ten hub genes identified, CDK1 and CDC45 were associated with unfavorable HNSCC prognosis, and three potential small molecule drugs for treating HNSCC were identified. Increased CDK1 expression was confirmed in HNSCC cells, and menadione, the top predicted potential drug, exerted significant inhibitory effects against HNSCC cell proliferation and markedly reversed CDK1 expression. Together, the findings of the present study suggest that the ten hub genes and pathways identified may be closely related to HNSCC pathogenesis. In particular, CDK1 and CDC45 overexpression could be reliable biomarkers for predicting unfavorable prognosis in patients with HNSCC, while the new candidate small molecules identified by CMap analysis provide new avenues for the development of potential drugs to treat HNSCC.

Targeting Glucose Metabolism to Overcome Resistance to Anticancer Chemotherapy in Breast Cancer

Breast cancer (BC) is the most prevalent cancer in women. BC is heterogeneous, with distinct phenotypical and morphological characteristics. These are based on their gene expression profiles, which divide BC into different subtypes, among which the triple-negative breast cancer (TNBC) subtype is the most aggressive one. The growing interest in tumor metabolism emphasizes the role of altered glucose metabolism in driving cancer progression, response to cancer treatment, and its distinct role in therapy resistance. Alterations in glucose metabolism are characterized by increased uptake of glucose, hyperactivated glycolysis, decreased oxidative phosphorylation (OXPHOS) component, and the accumulation of lactate. These deviations are attributed to the upregulation of key glycolytic enzymes and transporters of the glucose metabolic pathway. Key glycolytic enzymes such as hexokinase, lactate dehydrogenase, and enolase are upregulated, thereby conferring resistance towards drugs such as cisplatin, paclitaxel, tamoxifen, and doxorubicin. Besides, drug efflux and detoxification are two energy-dependent mechanisms contributing to resistance. The emergence of resistance to chemotherapy can occur at an early or later stage of the treatment, thus limiting the success and outcome of the therapy. Therefore, understanding the aberrant glucose metabolism in tumors and its link in conferring therapy resistance is essential. Using combinatory treatment with metabolic inhibitors, for example, 2-deoxy-D-glucose (2-DG) and metformin, showed promising results in countering therapy resistance. Newer drug designs such as drugs conjugated to sugars or peptides that utilize the enhanced expression of tumor cell glucose transporters offer selective and efficient drug delivery to cancer cells with less toxicity to healthy cells. Last but not least, naturally occurring compounds of plants defined as phytochemicals manifest a promising approach for the eradication of cancer cells via suppression of essential enzymes or other compartments associated with glycolysis. Their benefits for human health open new opportunities in therapeutic intervention, either alone or in combination with chemotherapeutic drugs. Importantly, phytochemicals as efficacious instruments of anticancer therapy can suppress events leading to chemoresistance of cancer cells. Here, we review the current knowledge of altered glucose metabolism in contributing to resistance to classical anticancer drugs in BC treatment and various ways to target the aberrant metabolism that will serve as a promising strategy for chemosensitizing tumors and overcoming resistance in BC.

Vitamin K3 thio-derivative: a novel specific apoptotic inducer in the doxorubicin-sensitive and -resistant cancer cells

Vitamin K₃, also known as menadione, is a synthetic lipid-soluble 2-methyl-1,4- naphthoquinone analogs of vitamin K. The vitamin K derivatives exhibit potent cytotoxicity against several cancer cell lines through ROS induction and mitochondrial dysfunction. We investigated vitamin K₃-inspired derivatives as potential apoptotic inducers and analyzed their mechanisms beyond apoptosis. The cytotoxicity of a panel of vitamin K₃ analogs was screened against 10 doxorubicin-sensitive and -resistant cancer cell lines overexpressing ATP-binding cassette transporters (P-glycoprotein, ABCB5, BCRP) or oncogenes (ΔEGFR) or with knockout of tumor suppressors (p53), Cell cycle arrest, apoptosis, cell migration, and microtubule formation were further investigated. The online tool SwissTargetPrediction was utilized for target prediction. Among the screened compounds, one vitamin K₃ thio-derivative (No. 45, VKT-1) exhibited the most potent cytotoxicity specifically against both drug-sensitive and -resistant cancer cell lines. In addition, VKT-1 arrested the cells at the G2/M phase and induced apoptosis as detected by flow cytometry. As predicted by SwissTargetPrediction, VKT-1 targeted microtubule-associated tau protein. Indeed, VKT-1 dramatically inhibited cell migration and microtubule formation in vitro. In conclusion, the synthetic vitamin K₃ thio-derivative (VKT-1) inhibited doxorubicin-sensitive and -resistant tumor cells by cell arrest, apoptosis induction, as well as, migration inhibition, and microtubule deterioration of U2OS-GFP-α-tubulin cells.