beta-Ionone-induced apoptosis in human osteosarcoma (U2os) cells occurs via a p53-dependent signaling pathway

New perspective: Symbiotic pattern and assembly mechanism of Cantharellus cibarius-associated bacteria

Cantharellus cibarius, an ectomycorrhizal fungus belonging to the Basidiomycetes, has significant medicinal and edible value, economic importance, and ecological benefits. However, C. cibarius remains incapable of artificial cultivation, which is thought to be due to the presence of bacteria. Therefore, much research has focused on the relationship between C. cibarius and bacteria, but rare bacteria are frequently overlooked, and symbiotic pattern and assembly mechanism of the bacterial community associated with C. cibarius remain unknown. In this study, the assembly mechanism and driving factors of both abundant and rare bacterial communities of C. cibarius were revealed by the null model. The symbiotic pattern of the bacterial community was examined using a co-occurrence network. Metabolic functions and phenotypes of the abundant and rare bacteria were compared using METAGENassist2, and the impacts of abiotic variables on the diversity of abundant and rare bacteria were examined using partial least squares path modeling. In the fruiting body and mycosphere of C. cibarius, there was a higher proportion of specialist bacteria compared with generalist bacteria. Dispersal limitation dominated the assembly of abundant and rare bacterial communities in the fruiting body and mycosphere. However, pH, 1-octen-3-ol, and total phosphorus of the fruiting body were the main driving factors of bacterial community assembly in the fruiting body, while available nitrogen and total phosphorus of the soil affected the assembly process of the bacterial community in the mycosphere. Furthermore, bacterial co-occurrence patterns in the mycosphere may be more complex compared with those in the fruiting body. Unlike the specific potential functions of abundant bacteria, rare bacteria may provide supplementary or unique metabolic pathways (such as sulfite oxidizer and sulfur reducer) to enhance the ecological function of C. cibarius. Notably, while volatile organic compounds can reduce mycosphere bacterial diversity, they can increase fruiting body bacterial diversity. Findings from this study further, our understanding of C. cibarius-associated microbial ecology.

Alternative mechanisms of action for the apoptotic activity of terpenoid-like chalcone derivatives

The structural basis of the cytotoxicity of terpenoid-like chalcone derivatives.

The potential chemotherapeutic effect of β-ionone and/or sorafenib against hepatocellular carcinoma via its antioxidant effect, PPAR-γ, FOXO-1, Ki-67, Bax, and Bcl-2 signaling pathways

Proliferation and apoptosis are two primary driving forces behind the pathogenesis of hepatocellular carcinoma (HCC). HCC is associated with Ki-67 and Bcl-2 overexpression, reduced Bax expression inducing disturbance of equilibrium between cellular proliferation and apoptosis, and exacerbated by reduced expression of PPAR-γ and FOXO-1. Our objective was to examine the mechanism by which the cyclic isoprenoid, β-ionone (βI), attenuated hepatocarcinogenesis and compare its possible anticancer activity with sorafenib (SF) as standard HCC treatment. HCC induction was achieved by supplying Wistar rats with 0.01% diethylnitrosamine (DENA) for 8 consecutive weeks by free access of drinking water. The effects of βI (160 mg/kg/day) administered orally were evaluated by biochemical, oxidative stress, macroscopical, and histopathological analysis. In addition, immunohistochemical assay for localization and expression of Bax and Bcl-2 and RT-PCR for expression levels of PPAR-γ, FOXO-1, and Ki-67 mRNA were performed. βI treatment significantly reduced the incidence, total number, and multiplicity of visible hepatocyte nodules, attenuated LPO, near-normal restoration of all cancer biomarkers, and antioxidant activities, indicating the chemotherapeutic impact of βI. Histopathological analysis of the liver confirmed that further. βI also induced pro-apoptotic protein Bax expression and reduced anti-apoptotic expression of Bcl-2 protein. Moreover, βI induced mRNA expression of tumor suppressor genes (PPAR-γ and FOXO-1) and decreased proliferative marker Ki-67 mRNA expression. For the first time, the present study provides evidence that βI exerts a major anticancer effect on DENA-induced HCC, at least in part, through inhibition of cell proliferation, oxidative stress, and apoptogenic signal induction mediated by downregulation of Bcl-2 and upregulation of Bax, PPAR-γ, and FOXO-1 expressions.

β-Ionone and its analogs as promising anticancer agents

β-Ionone is an end-ring analog of β-carotenoids which widely distributed in fruit and vegetables. Recent studies have demonstrated anti-proliferative, anti-metastatic and apoptosis induction properties of β-ionone in vitro and in vivo. Also, the studies have focused on investigating the β-ionone action on different types of malignant cells and the possible mechanisms of action. Moreover, the quest of new synthetic β-ionone-based compounds possessing anti-proliferative, anti-metastatic and apoptosis induction activities may enable the discovery of compounds which can be used in combination regimes thus overcoming tumor resistance to conventional anticancer agents. These new agents will also be useful for targeting distinct signaling pathways, to activate selectively mechanisms for apoptosis in cancer cells but devoid of undesirable side effects. In this paper, we reviewed the potentialities of β-ionone and related compounds in cancer prevention and chemotherapy.

β-Ionone derived chalcones as potent antiproliferative agents

A series of β-ionone derived chalcones were evaluated for cytotoxic activity against various human cancer cell lines using SRB dye assay. All the compounds displayed moderate to high cytotoxic effect against almost all the cancer cell lines. The results also revealed the effect of substituents of the aromatic ring on their inhibitory potential. In general, compounds bearing electron withdrawing groups such as nitro, fluoro, chloro and bromo showed more inhibitory potential than those bearing electron donating groups. The nitro substituted compound (7h) showed comparatively more inhibitory potential than other derivatives, therefore, it was further investigated for observing its effect on cell morphology in Chinese hamster ovary (CHO) cells by using phase contrast imaging, cell cycle analysis and annexin-FITC apoptosis assay. The treated cells exhibited the characteristics of apoptosis i.e. cell shrinkage, chromatin condensation and nuclear fragmentation, and induced the inhibition of cell proliferation by arresting the cells at G0 phase.

Synthesis of β-ionone derived chalcones as potent antimicrobial agents

A series of chalcones (3a-v) have been synthesized by condensation of β-ionone (1) with a variety of aldehydes (2a-v). The synthesized compounds have been screened for their in vitro antimicrobial activity against five bacterial and five fungal strains, using disc diffusion assay. The evaluated compounds display a wide range of activities, from completely inactive to the highly active compounds. Some of the compounds are also active against methicillin resistant staphylococcus aureus (MRSA).

The anti-metastatic efficacy of β-ionone and the possible mechanisms of action in human hepatocarcinoma SK-Hep-1 cells

β-Ionone (BI), a precursor for carotenoids, is widely distributed in fruit and vegetables. Recent in vitro studies have demonstrated the potential anti-metastatic effects of BI, but the mechanisms underlying such actions are not clear. Because liver cancer is the most endemic cancer in Taiwan and in a large region of the world, we hereby investigate the anti-metastatic effects of BI and its mechanisms of actions in a highly metastatic human hepatocarcinoma SK-Hep-1 cells. We show that incubation of cells with BI (1-50 μm) for 24 and 48 h significantly inhibited cell invasion, migration and adhesion. Mechanistically, incubation of cells with BI (1-50 μm) for 24 h resulted in the following: (1) significant inhibition of matrix metalloproteinase (MMP)-2, MMP-9 and urokinase-type plasminogen activator activities, (2) up-regulation of protein expression of the tissue inhibitor of matrix metalloproteinase (TIMP)-1, TIMP-2 and plasminogen activator inhibitor-1, (3) down-regulation of the expression of migration-related proteins, including focal adhesion kinase (FAK), phosphorylated form of FAK, Rho, Rac1 and Cdc42 and (4) up-regulation of the expression of nm23-H1 protein (P < 0·05). Overall, the results show that BI effectively inhibits the metastasis of SK-Hep-1 cells, and this effect involves the regulation of gene expression and signal pathways related to invasion and migration.

PNAS-4 expression and its relationship to p53 in colorectal cancer

PNAS-4 is a novel pro-apoptotic protein activated during the early response to DNA damage; however, the molecular mechanisms and pathways regulating PNAS-4 expression in tumors are not well understood. We hypothesized that PNAS-4 is a p53 down-stream target gene and designed this study. We searched online for putative p53-binding sites in the entire PNAS-4 gene and did not find any corresponding information. In HCT116 colon cancer cells, after being transfected with small interfering RNA to silence p53, the expressions of PNAS-4 and other known p53 target gene (Apaf1, Bax, Fas and Dr5) were determined by real-time PCR. We found that PNAS-4 was up-regulated while Apaf1, Bax, Fas and Dr5 were down-regulated. We then examined the expression of PNAS-4 and p53 mutation in colorectal cancer patients. PNAS-4 expressed both in colorectal cancers and normal tissues, but compared with paired control, PNAS-4 was up-regulated in cancers (P=0.018). PNAS-4 overexpression ratios were correlated to the p53 mutant status (P=0.001). The mean PNAS-4 expression levels of p53 mutant homozygote group and heterozygote group were higher than that of p53 wild type group (P=0.013). The expression ratios of PNAS-4 (every sample in relative to its paired normal mucosa) were different between negative lymph node metastasis (66% up-regulated, 34% down-regulated) and positive metastasis (42% up-regulated, 58% down-regulated). Taken together, these findings suggested that PNAS-4 was not a p53 target, but overexpression of PNAS-4 was correlated to p53 inactivity in colorectal cancer.

DLC-1 as a modulator of proliferation, apoptosis and migration in Burkitt's lymphoma cells

Deleted in liver cancer-1(DLC-1) gene expression is frequently down-regulated or deleted in many types of human cancer. To evaluate whether DLC-1 could be a therapeutic target for non-Hodgkin lymphoma (NHL), we examined the expressions of DLC-1 in Burkitt's lymphoma (BL) cell lines and tested the effects of DLC-1 on cellular growth and migration in BL cells. DLC-1 expression was not detectable in two human BL cell lines, Raji and Daudi, by reverse transcription-PCR. The transfer of DLC-1 into Raji and Daudi cell lines caused a significant inhibition in cell proliferation. This inhibitory effect on cell proliferation in BL cell lines was accompanied by induction of apoptosis. Furthermore, restoration of DLC-1 expression in BL cells had a significant inhibitory effect on migration. Our findings suggest that DLC-1 may play an important role in lymphoma by acting as a bona fide new tumor suppressor gene.

SDF-1α inhibits hypoxia and serum deprivation-induced apoptosis in mesenchymal stem cells through PI3K/Akt and ERK1/2 signaling pathways

Bone marrow-derived mesenchymal stem cells (BMSCs) have been demonstrated to be a promising cell sources for cardiac regeneration. Poor survival rate of transplanted BMSCs in infarcted myocardium attenuated its clinical application. It's reported that stromal-derived factor-1 (SDF-1) could protect progenitor cells including endothelial progenitor cells and embryonic stem cells from apoptosis. But little is known whether SDF-1α protein has the same protective effects on BMSCs under conditions of hypoxia and serum deprivation (hypoxia/SD). In present study, we verified that SDF-1α (0.50-2.0 μg/ml) inhibited hypoxia/SD induced apoptosis of BMSCs through mitochondrial pathway. After administration of SDF-1α, the loss of mitochondrial membrane potential and cytochrome c released from mitochondria to cytosol were significantly inhibited, and caspase 3 activity also declined. Furthermore, the effect of SDF-1α on mitochondrial pathway was neutralized by using PI3K inhibitor (Wortmannin) and ERK1/2 inhibitor (U0126). Our observations suggested that SDF-1α inhibits hypoxia/SD induced BMSCs apoptosis through PI3K/Akt and ERK1/2 signaling pathways. These data also imply that the anti-apoptotic effect mediated by SDF-1α may enhance cell survival after cell transplantation.