Development of human lactate dehydrogenase a inhibitors: high-throughput screening, molecular dynamics simulation and enzyme activity assay.

Lactate dehydrogenase A (LDHA) is highly expressed in many tumor cells and promotes the conversion of pyruvate to lactic acid in the glucose pathway, providing energy and synthetic precursors for rapid proliferation of tumor cells. Therefore, inhibition of LDHA has become a widely concerned tumor treatment strategy. However, the research and development of highly efficient and low toxic LDHA small molecule inhibitors still faces challenges. To discover potential inhibitors against LDHA, virtual screening based on molecular docking techniques was performed from Specs database of more than 260,000 compounds and Chemdiv-smart database of more than 1,000 compounds. Through molecular dynamics (MD) simulation studies, we identified 12 potential LDHA inhibitors, all of which can stably bind to human LDHA protein and form multiple interactions with its active central residues. In order to verify the inhibitory activities of these compounds, we established an enzyme activity assay system and measured their inhibitory effects on recombinant human LDHA. The results showed that Compound 6 could inhibit the catalytic effect of LDHA on pyruvate in a dose-dependent manner with an EC50 value of 14.54 ± 0.83 µM. Further in vitro experiments showed that Compound 6 could significantly inhibit the proliferation of various tumor cell lines such as pancreatic cancer cells and lung cancer cells, reduce intracellular lactic acid content and increase intracellular reactive oxygen species (ROS) level. In summary, through virtual screening and in vitro validation, we found that Compound 6 is a small molecule inhibitor for LDHA, providing a good lead compound for the research and development of LDHA related targeted anti-tumor drugs.

Transcriptomic landscape of sodium butyrate-induced growth inhibition of human colorectal cancer organoids.

Butyrate, a short-chain fatty acid, is predominantly produced by the decomposition of dietary fiber in the colon. Recent studies have shown that sodium butyrate (NaB) can inhibit cell proliferation and stimulate cell apoptosis in colorectal cancer (CRC) cells. However, the molecular mechanism behind NaB is still elusive. In this study, we aimed to explore the deeper mechanism of NaB in CRC by establishing a novel model - organoid. Organoids were generated from healthy and cancerous sites of CRC patients. RNA-seq experiments were undertaken using RNA isolated from the CRC organoids treated with NaB. Gene ontology analyses suggested that cell adhesion, cell-cell signaling, and extracellular matrix (ECM) organization were significantly enriched, with the manifested ECM related to the cell morphology variation in NaB-induced CRC organoids. The KEGG pathway and PPI analysis mainly focused on ECM-receptor interactions, as well as the PI3K-Akt signaling pathway. Interestingly, further analysis suggested that the upregulation of the expression of ITGB7 and ITGA2B was significantly associated with death by NaB-induced CRC organoids. In addition, NaB might further induce cell cycle arrest via the PI3K-Akt pathway, and thus cause cell death. Cumulatively, these results provide evidence that the ECM-integrin/PI3K axis may mediate phenotypic changes in the NaB-treated CRC organoid, which provides a broader perspective of the treatment and prognosis monitoring of CRC.

Antioxidant potential of Pediococcus pentosaceus strains from the sow milk bacterial collection in weaned piglets.

BACKGROUND: In modern animal husbandry, breeders pay increasing attention to improving sow nutrition during pregnancy and lactation to favor the health of neonates. Sow milk is a main food source for piglets during their first three weeks of life, which is not only a rich repository of essential nutrients and a broad range of bioactive compounds, but also an indispensable source of commensal bacteria. Maternal milk microorganisms are important sources of commensal bacteria for the neonatal gut. Bacteria from maternal milk may confer a health benefit on the host. METHODS: Sow milk bacteria were isolated using culturomics followed by identification using 16S rRNA gene sequencing. To screen isolates for potential probiotic activity, the functional evaluation was conducted to assess their antagonistic activity against pathogens in vitro and evaluate their resistance against oxidative stress in damaged Drosophila induced by paraquat. In a piglet feeding trial, a total of 54 newborn suckling piglets were chosen from nine sows and randomly assigned to three treatments with different concentrations of a candidate strain. Multiple approaches were carried out to verify its antioxidant function including western blotting, enzyme activity analysis, metabolomics and 16S rRNA gene amplicon sequencing. RESULTS: The 1240 isolates were screened out from the sow milk microbiota and grouped into 271 bacterial taxa based on a nonredundant set of 16S rRNA gene sequencing. Among 80 Pediococcus isolates, a new Pediococcus pentosaceus strain (SMM914) showed the best performance in inhibition ability against swine pathogens and in a Drosophila model challenged by paraquat. Pretreatment of piglets with SMM914 induced the Nrf2-Keap1 antioxidant signaling pathway and greatly affected the pathways of amino acid metabolism and lipid metabolism in plasma. In the colon, the relative abundance of Lactobacillus was significantly increased in the high dose SMM914 group compared with the control group. CONCLUSION: P. pentosaceus SMM914 is a promising probiotic conferring antioxidant capacity by activating the Nrf2-Keap1 antioxidant signaling pathway in piglets. Our study provided useful resources for better understanding the relationships between the maternal microbiota and offspring. Video Abstract.

An Anti-Cancer Peptide LVTX-8 Inhibits the Proliferation and Migration of Lung Tumor Cells by Regulating Causal Genes' Expression in p53-Related Pathways.

Spider venom has been found to show its anticancer activity in a variety of human malignancies, including lung cancer. In this study, we investigated the anti-cancer peptide toxin LVTX-8, with linear amphipathic alpha-helical conformation, designed and synthesized from the cDNA library of spider Lycosa vittata. Multiple cellular methods, such as CCK-8 assay, flow cytometry, colony formation assay, Transwell invasion and migration assay, were performed to detect peptide-induced cell growth inhibition and anti-metastasis in lung cancer cells. Our results demonstrated that LVTX-8 displayed strong cytotoxicity and anti-metastasis towards lung cancer in vitro. Furthermore, LVTX-8 could suppress the growth and metastasis of lung cancer cells (A549 and H460) in nude mouse models. Transcriptomics, integrated with multiple bioinformatics analysis, suggested that the molecular basis of the LVTX-8-mediated inhibition of cancer cell growth and metastasis manifested in two aspects: Firstly, it could restrain the activity of cancer cell division and migration through the functional pathways, including "p53 hypoxia pathway" and "integrin signaling". Secondly, it could regulate the expression level of apoptotic-related proteins, which may account for programmed apoptosis of cancer cells. Taken together, as an anticancer peptide with high efficiency and acceptable specificity, LVTX-8 may become a potential precursor of a therapeutic agent for lung cancer in the future.

FOXA1 defines cancer cell specificity.

A transcription factor functions differentially and/or identically in multiple cell types. However, the mechanism for cell-specific regulation of a transcription factor remains to be elucidated. We address how a single transcription factor, forkhead box protein A1 (FOXA1), forms cell-specific genomic signatures and differentially regulates gene expression in four human cancer cell lines (HepG2, LNCaP, MCF7, and T47D). FOXA1 is a pioneer transcription factor in organogenesis and cancer progression. Genomewide mapping of FOXA1 by chromatin immunoprecipitation sequencing annotates that target genes associated with FOXA1 binding are mostly common to these cancer cells. However, most of the functional FOXA1 target genes are specific to each cancer cell type. Further investigations using CRISPR-Cas9 genome editing technology indicate that cell-specific FOXA1 regulation is attributable to unique FOXA1 binding, genetic variations, and/or potential epigenetic regulation. Thus, FOXA1 controls the specificity of cancer cell types. We raise a "flower-blooming" hypothesis for cell-specific transcriptional regulation based on these observations.

Synthesis and discovery of autophagy inducers for A549 and H460 lung cancer cells, novel 1-(2'-hydroxy-3'-aroxypropyl)-3-aryl-1H-pyrazole-5-carbohydrazide derivatives.

A series of novel 1-(2'-hydroxy-3'-aroxypropyl)-3-aryl-1H-pyrazole-5-carbohydrazide derivatives were synthesized, and the effects of the compounds on A549 cell growth were investigated. The results showed that all of the 1-(2'-hydroxy-3'-aroxypropyl)-3-aryl-1H-pyrazole-5-carbohydrazide derivatives 2 could inhibit the growth of A549 cells in dosage- and time-dependent manners. Typically, compound 2a and 2d induced A549 cells to autophagy but did not cause apoptosis and necrosis in the cells, and 2d had the most autophagy inducing effect in H460 cells. More importantly, 2a and 2d did not inhibit the growth of HUVEC cells.