Lp16-PSP, a Member of YjgF/YER057c/UK114 Protein Family Induces Apoptosis and p21WAF1/CIP1 Mediated G1 Cell Cycle Arrest in Human Acute Promyelocytic Leukemia (APL) HL-60 Cells

RidA Proteins Protect against Metabolic Damage by Reactive Intermediates

The Rid (YjgF/YER057c/UK114) protein superfamily was first defined by sequence homology with available protein sequences from bacteria, archaea, and eukaryotes (L. Parsons, N. Bonander, E. Eisenstein, M. Gilson, et al., Biochemistry 42:80-89, 2003, https://doi.org/10.1021/bi020541w). The archetypal subfamily, RidA (reactive intermediate deaminase A), is found in all domains of life, with the vast majority of free-living organisms carrying at least one RidA homolog. In over 2 decades, close to 100 reports have implicated Rid family members in cellular processes in prokaryotes, yeast, plants, and mammals. Functional roles have been proposed for Rid enzymes in amino acid biosynthesis, plant root development and nutrient acquisition, cellular respiration, and carcinogenesis. Despite the wealth of literature and over a dozen high-resolution structures of different RidA enzymes, their biochemical function remained elusive for decades. The function of the RidA protein was elucidated in a bacterial model system despite (i) a minimal phenotype of ridA mutants, (ii) the enzyme catalyzing a reaction believed to occur spontaneously, and (iii) confusing literature on the pleiotropic effects of RidA homologs in prokaryotes and eukaryotes. Subsequent work provided the physiological framework to support the RidA paradigm in Salmonella enterica by linking the phenotypes of mutants lacking ridA to the accumulation of the reactive metabolite 2-aminoacrylate (2AA), which damaged metabolic enzymes. Conservation of enamine/imine deaminase activity of RidA enzymes from all domains raises the likelihood that, despite the diverse phenotypes, the consequences when RidA is absent are due to accumulated 2AA (or a similar reactive enamine) and the diversity of metabolic phenotypes can be attributed to differences in metabolic network architecture. The discovery of the RidA paradigm in S. enterica laid a foundation for assessing the role of Rid enzymes in diverse organisms and contributed fundamental lessons on metabolic network evolution and diversity in microbes. This review describes the studies that defined the conserved function of RidA, the paradigm of enamine stress in S. enterica, and emerging studies that explore how this paradigm differs in other organisms. We focus primarily on the RidA subfamily, while remarking on our current understanding of the other Rid subfamilies. Finally, we describe the current status of the field and pose questions that will drive future studies on this widely conserved protein family to provide fundamental new metabolic information.

Lemon Balm Extracts Prevent Breast Cancer Progression In Vitro and In Ovo on Chorioallantoic Membrane Assay

Breast cancer is the most frequently diagnosed malignant pathology, representing the primary cause of cancer death in women. Natural products are an appealing strategy to limit the progression of the disease. Targeting angiogenesis in breast cancer may positively impact on poor prognosis of breast cancer. As source of natural compounds, we investigated the leaves of Melissa officinalis L. (MO), known as lemon balm, an aromatic plant that spontaneously grows in the South and Western areas of Romania, being traditionally recommended as anxiolytic, antispasmodic, or as digestive remedy. Our aim was to investigate the phytochemical profiling and the antiangiogenic and chemopreventive bioactivity of MO from Banat region, on breast cancer. Two ethanolic extracts of MO (MOE96 and MOE70) and one methanolic extract (MOM80) were subjected to polyphenol and triterpene profiling by HPLC-MS, and the antioxidant capacity was evaluated. The antiangiogenic potential was investigated using the chorioallantoic membrane assay (CAM). The MTT(3-(4,5-dimethylthiazol-2-yl)-2-5-diphenyltetrazolium bromide) assay was used to investigate the cytotoxic effects on MCF-7 and MDA-MB-231breast cancer cells, as well as on MCF-10A normal breast epithelial cells, while apoptosis was performed by DAPI staining. Rosmarinic acid (RA) and ursolic acid (UA) were revealed as dominant phytocompounds. The highest concentration in phytochemicals were found in MOM80; MOE96 was more concentrated in UA, while MOE70 extracted more RA. MOE96 inhibited cancer progression and angiogenesis in the in ovo CAM model using MDA-MB-231 cells, inhibiting breast cancer progression and angiogenesis for the MDA-MB-231 breast cancer cell line; no secondary tumoral areas were registered, indicative for a preventive effect against breast tumor cell invasiveness. The highest cell inhibitory activity was also exhibited by MOE96, in particular against the estrogen receptor positive MCF7 breast cancer cell line, with no cytotoxic effect on healthy cells. The estrogen receptor positive MCF7 cell line proved to be more sensitive to the extract antiproliferative activity than the triple negative MDA-MB-231 breast cancer cell line. Nevertheless, the chemopreventive potential of MOE96 extract is phenotype-dependent and is rather related to the apoptosis and antiangiogenic effects suggesting a multitargeted mechanism of action due to its multiple compound composition next to a concentration ratio of RA : UA in favor of UA.

LP1 from Lentinula edodes C91-3 Induces Autophagy, Apoptosis and Reduces Metastasis in Human Gastric Cancer Cell Line SGC-7901

Present study aimed to elucidate the anticancer effect and the possible molecular mechanism underlying the action of Latcripin 1 (LP1), from the mushroom Lentinula edodes strain C91-3 against gastric cancer cell lines SGC-7901 and BGC-823. Cell viability was measured by Cell Counting Kit-8 (CCK-8); morphological changes were observed by phase contrast microscope; autophagy was determined by transmission electron microscope and fluorescence microscope. Apoptosis and cell cycle were assessed by flow cytometer; wound-healing, transwell migration and invasion assays were performed to investigate the effect of LP1 on gastric cancer cell's migration and invasion. Herein, we found that LP1 resulted in the induction of autophagy by the formation of autophagosomes and conversion of light chain 3 (LC3I into LC3II. LP1 up-regulated the expression level of autophagy-related gene (Atg7, Atg5, Atg12, Atg14) and Beclin1; increased and decreased the expression level of pro-apoptotic (Bax) and anti-apoptotic (Bcl-2) proteins respectively, along with the activation of Caspase-3. At lower-doses, LP1 have shown to arrest cells in the S phase of the cell cycle and decreased the expression level of matrix metalloproteinase MMP-2 and MMP-9. In addition, it has also been shown to regulate the phosphorylation of one of the most hampered gastric cancer pathway, that is, protein kinase B/mammalian target of rapamycin (Akt/mTOR) channel and resulted in cell death. These findings suggested LP1 as a potential natural anti-cancer agent, for exploring the gastric cancer therapies and as a contender for further in vitro and in vivo investigations.