1H-NMR metabolomics analysis identifies hypoxanthine as a novel metastasis-associated metabolite in breast cancer.

Breast cancer is one of the leading causes of death in females, mainly because of metastasis. Oncometabolites, produced via metabolic reprogramming, can influence metastatic signaling cascades. Accordingly, and based on our previous results, we propose that metabolites from highly metastatic breast cancer cells behave differently from less-metastatic cells and may play a significant role in metastasis. For instance, we aim to identify these metabolites and their role in breast cancer metastasis. Less metastatic cells (MCF-7) were treated with metabolites secreted from highly metastatic cells (MDA-MB-231) and the gene expression of three epithelial-to-mesenchymal transition (EMT) markers including E-cadherin, N-cadherin and vimentin were examined. Some metabolites secreted from MDA-MB-231 cells significantly induced EMT activity. Specifically, hypoxanthine demonstrated a significant EMT effect and increased the migration and invasion effects of MCF-7 cells through a hypoxia-associated mechanism. Hypoxanthine exhibited pro-angiogenic effects via increasing the VEGF and PDGF gene expression and affected lipid metabolism by increasing the gene expression of PCSK-9. Notably, knockdown of purine nucleoside phosphorylase, a gene encoding for an important enzyme in the biosynthesis of hypoxanthine, and inhibition of hypoxanthine uptake caused a significant decrease in hypoxanthine-associated EMT effects. Collectively for the first time, hypoxanthine was identified as a novel metastasis-associated metabolite in breast cancer cells and represents a promising target for diagnosis and therapy.

Optimum inhibition of MCF-7 breast cancer cells by efficient targeting of the macropinocytosis using optimized paclitaxel-loaded nanoparticles.

AIMS: Breast cancer (BC) is the third leading cause of death among other cancer types. Worldwide, it is the most common harmful disease in women, representing 1/4 of all cancers. Treatment of BC remains an ongoing challenge to most researchers. Understanding how cancer cells differ from normal cells can enhance drug targeting and overall disease progression. Endocytosis is a major physiological process modified in cancer cells and affects the cellular uptake of chemotherapeutic agents. MCF-7 breast cancer cells exhibit constitutive macropinocytic activity in comparison to normal non-macropinocytic MCF-10A breast cells. Therefore, we hypothesized that blocking the macropinocytosis mechanism in MCF-7 cells may inhibit the cancer progression while maintaining the safety of normal cells. MAIN METHODS: Using nano-precipitation technique, paclitaxel-PLGA-NPs were successfully prepared in the size range and charge required to opt for macropinocytosis in MCF-7 cells. KEY FINDINGS: Uptake and endocytosis inhibitor assays indicated that the developed NPs acquired size and surface charges that efficiently target macropinocytosis of MCF-7 cells. Paclitaxel-loaded PLGA-NPs showed higher efficacy against MCF-7 cells, while providing no toxicity on normal MCF-10A cells. Metabolomics analysis indicated the nutrients deprivation because of occupying the macropinocytosis. However, treatment of fresh MCF-7 cancer cells by metabolites secreted from PLGA-NPs-treated MCF-7 cells showed a potential metastatic activity. Thus, co- administration with an anti-metastatic drug is advised. SIGNIFICANCE: Collectively, adjusting the size and surface characteristics of a drug can critically control its cellular uptake, affecting the efficacy of drugs and the microenvironment of cancer cells.

New Bioactive Fused Triazolothiadiazoles as Bcl-2-Targeted Anticancer Agents.

A series of 3-(6-substituted phenyl-[1,2,4]-triazolo[3,4-b]-[1,3,4]-thiadiazol-3-yl)-1H-indoles (5a-l) were designed, synthesized and evaluated for anti-apoptotic Bcl-2-inhibitory activity. Synthesis of the target compounds was readily accomplished through a reaction of acyl hydrazide (1) with carbon disulfide in the presence of alcoholic potassium hydroxide to afford the corresponding intermediate potassium thiocarbamate salt (2), which underwent cyclization reaction in the presence of excess hydrazine hydrate to the corresponding triazole thiol (3). Further cyclisation reaction with substituted benzoyl chloride derivatives in the presence of phosphorous oxychloride afforded the final 6-phenyl-indol-3-yl [1,2,4]-triazolo[3,4-b]-[1,3,4]-thiadiazole compounds (5a-l). The novel series showed selective sub-micromolar IC50 growth-inhibitory activity against Bcl-2-expressing human cancer cell lines. The most potent 6-(2,4-dimethoxyphenyl) substituted analogue (5k) showed selective IC50 values of 0.31-0.7 µM against Bcl-2-expressing cell lines without inhibiting the Bcl-2-negative cell line (Jurkat). ELISA binding affinity assay (interruption of Bcl-2-Bim interaction) showed potent binding affinity for (5k) with an IC50 value of 0.32 µM. Moreover, it fulfils drug likeness criteria as a promising drug candidate.

Dyslipidemia in breast cancer patients increases the risk of SAR-CoV-2 infection.

Breast cancer (BC) is the most diagnosed and second leading cause of death among women worldwide. Elevated levels of lipids have been reported in BC patients. On the other hand, lipids play an important role in coronavirus infections including the newly emerged disease caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and designated COVID-19 by WHO. Cancer patients including BC have been reported to be at higher risk of SARS-CoV-2 infection, which is mostly attributed to the chronic immunosuppressive status of cancer patients along with the use of cytotoxic drugs. Here in this review, we highlighted the role of dyslipidemia associated with BC patients in the incidence and severity of SARS-CoV-2 infection. Elevated levels of lipids namely phospholipids, cholesterol, sphingolipids, and eicosanoids in the serum of BC patients and their re-localization to the alveolar spaces can increase susceptibility and/or severity due to SARA-CoV-2 infection. Therefore, manipulation of dyslipidemia in BC patients should be recommended as prophylactic and therapy against SARS-CoV-2 infection.