In nature plants are often simultaneously challenged by different biotic and abiotic stresses. Although the mechanisms underlying plant responses against single stress have been studied considerably, plant tolerance mechanisms under combined stress is not understood. Also, the mechanism used to combat independently and sequentially occurring many number of biotic and abiotic stresses has also not systematically studied. From this context, in this study, we attempted to explore the shared response of sunflower plants to many independent stresses by using meta-analysis of publically available transcriptome data and transcript profiling by quantitative PCR. Further, we have also analyzed the possible role of the genes so identified in contributing to combined stress tolerance. Meta-analysis of transcriptomic data from many abiotic and biotic stresses indicated the common representation of oxidative stress responsive genes. Further, menadione-mediated oxidative stress in sunflower seedlings showed similar pattern of changes in the oxidative stress related genes. Based on this a large scale screening of 55 sunflower genotypes was performed under menadione stress and those contrasting in oxidative stress tolerance were identified. Further to confirm the role of genes identified in individual and combined stress tolerance the contrasting genotypes were individually and simultaneously challenged with few abiotic and biotic stresses. The tolerant hybrid showed reduced levels of stress damage both under combined stress and few independent stresses. Transcript profiling of the genes identified from meta-analysis in the tolerant hybrid also indicated that the selected genes were up-regulated under individual and combined stresses. Our results indicate that menadione-based screening can identify genotypes not only tolerant to multiple number of individual biotic and abiotic stresses, but also the combined stresses.

Vitis coignetiae Pulliat (Meoru in Korea) has been used in Korean folk medicine for the treatment of inflammatory diseases and cancers. Evidence suggests that NF-κB activation is mainly involved in cancer cell proliferation, invasion, angiogenesis, and metastasis. TNF-α also enhances the inflammatory process in tumor development. Recently, flavonoids from plants have been reported to have inhibitory effects on NF-κB activities. We investigated the effects of anthocyanins extracted from the fruits of Vitis coignetiae Pulliat (AIM, anthocyanins isolated from Meoru (AIM)) on TNF-α-induced NF-κB activities in MCF-7 human breast cancer cells and the molecules involved in AIM-induced anti-cancer effects, especially on cancer metastasis. We performed cell viability assay, gelatin zymography, invasion assay, and western blot analysis to unravel the anti-NF-κB activity of AIMs on MCF-7 cells. AIM suppressed the TNF-α effects on the NF-κB-regulated proteins involved in cancer cell proliferation (COX-2, C-myc), invasion, and angiogenesis (MMP-2, MMP9, ICAM-1, and VEGF). AIM also increased the expression of E-cadherin, which is one of the hallmarks of the epithelial-mesenchymal transition (EMT) process. In conclusion, this study demonstrates that the anthocyanins isolated from the fruits of Vitis coignetiae Pulliat acts as an inhibitor of TNF-α induced NF-κB activation, and subsequent downstream molecules involved in cancer proliferation, invasion, adhesion, angiogenesis, and thus have anti-metastatic activities in MCF-7 breast cancer cells.

Anthocyanins isolated from Vitis coignetiae Pulliat (Meoru in Korea) (AIMs) have various anti-cancer properties by inhibiting Akt and NF-κB which are involved in drug resistance. Cisplatin (CDDP) is one of the popular anti-cancer agents. Studies reported that MCF-7 human breast cancer cells have high resistance to CDDP compared to other breast cancer cell lines. In this study, we confirmed CDDP resistance of MCF-7 cells and tested whether AIMs can overcome CDDP resistance of MCF-7 cells. Cell viability assay revealed that MCF-7 cells were more resistant to CDDP treatment than MDA-MB-231 breast cancer cells exhibiting aggressive and high cancer stem cell phenotype. AIMs significantly augmented the efficacy of CDDP with synergistic effects on MCF-7 cells. Molecularly, Western blot analysis revealed that CDDP strongly increased Akt and moderately reduced p-NF-κB and p-IκB and that AIMs inhibited CDDP-induced Akt activation, and augmented CDDP-induced reduction of p-NF-κB and p-IκB in MCF-7 cells. In addition, AIMs significantly downregulated an anti-apoptotic protein, XIAP, and augmented PARP-1 cleavage in CDDP-treated MCF-7 cells. Moreover, under TNF-α treatment, AIMs augmented CDDP efficacy with inhibition of NF-κB activation on MCF-7 cells. In conclusion, AIMs enhanced CDDP sensitivity by inhibiting Akt and NF-κB activity of MCF-7 cells that show relative intrinsic CDDP resistance.

The Korean Petasites japonicus is a perennial plant used in folk medicine as a remedy for many diseases and popularly consumed as spring greens. Ten polyphenols were characterized from the leaves, stems and roots of this plant via high-performance liquid chromatography-tandem mass spectrometry. Individual polyphenols were quantified for the first time using calibration curves of six structurally related external standards. Validation data indicated that coefficients of determinations (R ) were ≥0.9702 for all standards. Recoveries measured at 50 and 100 mg/L were 80.0-91.9 and 80.3-105.3%, respectively. Precisions at these two concentration levels were 0.7-6.1 and 1.1-5.5%, respectively. The total number of identified components was largest for the leaves and smallest for the stems. The leaf and root polyphenolic extracts showed anti-inflammatory effects by inducing LPS-activated COX-2 and iNOS protein levels in mouse macrophage RAW 264.7 cells. The antioxidant capacity of the polyphenols, when evaluated for DPPH (α,α-diphenyl-β-picrylhydrazyl) , ABTS [2-2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)] and superoxide radical scavenging activities, and in ferric reducing ability of plasma (FRAP) assays, was highest in the leaf and lowest in the stem. This trend suggests that the antioxidant capacities depend primarily on polyphenol concentration in each tissue. The current findings suggest that polyphenols derived from P. japonicas tissues could have potential as functional health foods.

We previously demonstrated that anthocyanins from the fruits of Vitis coignetiae Pulliat (AIMs) induced the apoptosis of hepatocellular carcinoma cells. However, many researchers argued that the concentrations of AIMs were too high for in vivo experiments. Therefore, we performed in vitro at lower concentrations and in vivo experiments for the anti-cancer effects of AIMs. AIMs inhibited the cell proliferation of Hep3B cells in a dose-dependent manner with a maximum concentration of 100 µg/mL. AIMs also inhibited the invasion and migration at 100 µg/mL concentration with or without the presence of TNF-α. To establish the relevance between the in vitro and in vivo results, we validated their effects in a Xenograft model of Hep3B human hepatocellular carcinoma cells. In the in vivo test, AIMs inhibited the tumorigenicity of Hep3B cells in the xenograft mouse model without showing any clinical signs of toxicity or any changes in the body weight of mice. AIMs inhibited the activation NF-κB and suppressed the NF-κB-regulated proteins, intra-tumoral microvessel density (IMVD) and the Ki67 activity of Hep3B xenograft tumors in athymic nude mice. In conclusion, this study indicates that AIMs have anti-cancer effects (inhibition of proliferation, invasion, and angiogenesis) on human hepatocellular carcinoma xenograft through the inhibition of NF-κB and its target protein.

Breast cancer is one of the major causes of deaths due to cancer, especially in women. The crucial barrier for breast cancer treatment is resistance to radiation therapy, one of the important local regional therapies. We previously established and characterized radio-resistant MDA-MB-231 breast cancer cells (RT-R-MDA-MB-231 cells) that harbor a high expression of cancer stem cells (CSCs) and the EMT phenotype. In this study, we performed antibody array analysis to identify the hub signaling mechanism for the radiation resistance of RT-R-MDA-MB-231 cells by comparing parental MDA-MB-231 (p-MDA-MB-231) and RT-R-MDA-MB-231 cells. Antibody array analysis unveiled that the MAPK1 protein was the most upregulated protein in RT-R-MDA-MB-231 cells compared to in p-MDA-MB-231 cells. The pathway enrichment analysis also revealed the presence of MAPK1 in almost all enriched pathways. Thus, we used an MEK/ERK inhibitor, PD98059, to block the MEK/ERK pathway and to identify the role of MAPK1 in the radio-resistance of RT-R-MDA-MB-231 cells. MEK/ERK inhibition induced cell death in both p-MDA-MB-231 and RT-R-MDA-MB-231 cells, but the death mechanism for each cell was different; p-MDA-MB-231 cells underwent apoptosis, showing cell shrinkage and PARP-1 cleavage, while RT-R-MDA-MB-231 cells underwent necroptosis, showing mitochondrial dissipation, nuclear swelling, and an increase in the expressions of CypA and AIF. In addition, MEK/ERK inhibition reversed the radio-resistance of RT-R-MDA-MB-231 cells and suppressed the increased expression of CSC markers (CD44 and OCT3/4) and the EMT phenotype (β-catenin and N-cadherin/E-cadherin). Taken together, this study suggests that activated ERK signaling is one of the major hub signals related to the radio-resistance of MDA-MB-231 breast cancer cells.

Lung cancer is one of the most lethal forms of cancer, with a very high mortality rate. The precise pathophysiology of lung cancer is not well understood, and pertinent information regarding the initiation and progression of lung cancer is currently a crucial area of scientific investigation. Enhanced knowledge about the disease will lead to the development of potent therapeutic interventions. Extracellular vesicles (EVs) are membrane-bound heterogeneous populations of cellular entities that are abundantly produced by all cells in the human body, including the tumor cells. A defined class of EVs called small Extracellular Vesicles (sEVs or exosomes) carries key biomolecules such as RNA, DNA, Proteins and Lipids. Exosomes, therefore, mediate physiological activities and intracellular communication between various cells, including constituent cells of the tumor microenvironment, namely stromal cells, immunological cells, and tumor cells. In recent years, a surge in studying tumor-associated non-coding RNAs (ncRNAs) has been observed. Subsequently, studies have also reported that exosomes abundantly carry different species of ncRNAs and these exosomal ncRNAs are functionally involved in cancer initiation and progression. Here, we discuss the function of exosomal ncRNAs, such as miRNAs and long non-coding RNAs, in the pathophysiology of lung tumors. Further, the future application of exosomal-ncRNAs in clinics as biomarkers and therapeutic targets in lung cancer is also discussed due to the multifaceted influence of exosomes on cellular physiology.

Emerging evidence suggests that breast cancer stem cells (BCSCs), and epithelial–mesenchymal transition (EMT) may be involved in resistance to doxorubicin. However, it is unlear whether the doxorubicin-induced EMT and expansion of BCSCs is related to cancer dormancy, or outgrowing cancer cells with maintaining resistance to doxorubicin, or whether the phenotypes can be transferred to other doxorubicin-sensitive cells. Here, we characterized the phenotype of doxorubicin-resistant TNBC cells while monitoring the EMT process and expansion of CSCs during the establishment of doxorubicin-resistant MDA-MB-231 human breast cancer cells (DRM cells). In addition, we assessed the potential signaling associated with the EMT process and expansion of CSCs in doxorubicin-resistance of DRM cells. DRM cells exhibited morphological changes from spindle-shaped MDA-MB-231 cells into round-shaped giant cells. They exhibited highly proliferative, EMT, adhesive, and invasive phenotypes. Molecularly, they showed up-regulation of Cyclin D1, mesenchymal markers (β-catenin, and N-cadherin), MMP-2, MMP-9, ICAM-1 and down-regulation of E-cadherin. As the molecular mechanisms responsible for the resistance to doxorubicin, up-regulation of EGFR and its downstream signaling, were suggested. AKT and ERK1/2 expression were also increased in DRM cells with the advancement of resistance to doxorubicin. Furthermore, doxorubicin resistance of DRM cells can be transferred by autocrine signaling. In conclusion, DRM cells harbored EMT features with CSC properties possessing increased proliferation, invasion, migration, and adhesion ability. The doxorubicin resistance, and doxorubicin-induced EMT and CSC properties of DRM cells, can be transferred to parental cells through autocrine signaling. Lastly, this feature of DRM cells might be associated with the up-regulation of EGFR.