M2 Macrophages Mediate the Resistance of Gastric Adenocarcinoma Cells to 5-Fluorouracil through the Expression of Integrin ß3, Focal Adhesion Kinase, and Cofilin.

Tumor microenvironment components dictate the growth and progression of various cancers. Tumor-associated macrophages are the most predominant cells in TME and play a major role in cancer invasiveness. Gastric cancer is one of the most common cancers in Asia, and recently, various cases of resistance to fluorouracil treatment have been reported. In this study, we investigated the role of alternatively activated macrophages in the resistance of AGS gastric cancer cells to fluorouracil. THP-1 cells were polarized using recombinant human IL-4, then were cocultured with AGS cells treated with fluorouracil. Cell viability, Western blot, immunofluorescence, and cell invasion were performed for this investigation. Our results demonstrated that polarized macrophages initiated the survival of treated AGS cells and induced the resistance in AGS by upregulating the expression of integrin ß3, focal adhesion protein (FAK), and cofilin proteins. These results reveal that integrin ß3, focal adhesion protein (FAK), and cofilin proteins are potential targets for the improvement of fluorouracil efficacy in gastric cancer treatment.

Engineering and Preclinical Evaluation of Western Reserve Oncolytic Vaccinia Virus Expressing A167Y Mutant Herpes Simplex Virus Thymidine Kinase.

Viral replication of thymidine kinase deleted (tk-) vaccinia virus (VV) is attenuated in resting normal cells, enabling cancer selectivity, however, replication potency of VV-tk- appears to be diminished in cancer cells. Previously, we found that wild-type herpes simplex virus (HSV)-tk (HSV-tk) disappeared in most of the recombinant VV after multiple screenings, and only a few recombinant VV containing naturally mutated HSV-tk remained stable. In this study, VV-tk of western reserve (WR) VV was replaced by A167Y mutated HSV-tk (HSV-tk418m), to alter nucleoside selectivity from broad spectrum to purine exclusive selectivity. WOTS-418 remained stable after numerous passages. WOTS-418 replication was significantly attenuated in normal cells, but cytotoxicity was almost similar to that of wild type WR VV in cancer cells. WOTS-418 showed no lethality following a 5 × 108 PFU intranasal injection, contrasting WR VV, which showed 100% lethality at 1 × 105 PFU. Additionally, ganciclovir (GCV) but not BvdU inhibited WOTS-418 replication, confirming specificity to purine nucleoside analogs. The potency of WOTS-418 replication inhibition by GCV was > 10-fold higher than that of our previous truncated HSV-tk recombinant OTS-412. Overall, WOTS-418 demonstrated robust oncolytic efficacy and pharmacological safety which may delegate it as a candidate for future clinical use in OV therapy.

In vitro induction of endoplasmic reticulum stress in human cervical adenocarcinoma HeLa cells by fucoidan.

Fucoidan is a sulfated hetero-polysaccharide, found in cell-wall composition of brown algae. Recent studies have reported the role of fucoidan in the induction of Endoplasmic Reticulum (ER) stress-related cell death in cancer cells but the mechanism of action of fucoidan in cervical HeLa cells is not well-known. The purpose of this study was to investigate if fucoidan induces HeLa cells death through ER-stress-related cell death and G1 phase arrest. 200-600 µg/ml concentrations of fucoidan inhibited the proliferation of HeLa cells after 48 h of treatment while investigated normal cell lines (HaCaT: Keratinocytes and HEK-293: embryonic kidney) were not affected. The exposure of HeLa cells to these concentrations of fucoidan induced phosphorylation of ER stress sensors followed by upregulation of Bip/GRP78, CHOP expression which triggered a buildup of malfolded proteins in ER, therefore, initiating unfolded protein response (UPR) mechanism. In addition, intracellular calcium levels were elevated following the treatment suggesting that this contributed to the ER stress-induced apoptosis. Fucoidan treatment caused G1phase arrest by inducting CDKIs and inhibiting CDKs and Cyclins as well as apoptosis by activating the mitochondrial-dependent pathway in HeLa cells. We demonstrated that Fucoidan inhibits HeLa cells proliferation by inducing apoptosis, G1 phase arrest, ER stress, and mitochondrial-mediated apoptosis.

Induction of apoptosis and G1 phase cell cycle arrest by Aster incisus in AGS gastric adenocarcinoma cells.

In recent decades, various bioactive compounds from plants have been investigated for their potential use in the treatment of diseases in humans. Aster incisus extract (AIE) is the extract of a common plant that is mostly found in Asia. It has traditionally been used for medicinal purposes in South Korea. In this study, we evaluated the potential anticancer effects of a methanolic extract of Aster incisus in a normal human cell line (HaCaT keratinocytes) and in 4 different types of human cancer cell lines (A549, lung cancer; Hep3B, liver cancer; MDA­MB­231, breast cancer; and AGS, gastric cancer). The HaCaT, A549, Hep3B, MDA­MB­231 and AGS cells were treated with various concentrations of AIE and following treatment, cell survival was evaluated. Additional analyses, such as WST-1 assay, western blot analysis, DAPI staining, flow cytometry, immunofluorescence staining and wound healing assay were performed to elucidate the mechanisms and pathways involved in the cell death induced by AIE. Treatment with AIE induced morphological changes and considerably reduced the viability of the both normal and cancer cell lines. Further analysis of the AGS gastric cancer cells revealed that AIE led to the induction of apoptosis and a high accumulation of cells in the G1 cell phase following treatment with AIE in a dose-dependent manner. The results also revealed that AIE successfully suppressed the migration of the AIE-treated AGS cells. The results of western blot analysis indicated that AIE increased the expression of pro-apoptotic proteins, particularly Bid, Bad, Bak, cytochrome c, apoptosis inducing factor (AIF), cleaved caspase­3, -8 and -9 and cleaved poly(ADP-ribose) polymerase (PARP). Additionally, AIE decreased the expression of the anti-apoptotic proteins, Bcl-2 and Bcl-xL. On the whole, the findings of this study demonstrate that AIE induces apoptosis through the activation of the caspase­dependent pathway mediated by the mitochondrial pathway and by arresting the cell cycle in AGS cells.

Anti-Inflammatory Effects of Aster incisus through the Inhibition of NF-κB, MAPK, and Akt Pathways in LPS-Stimulated RAW 264.7 Macrophages.

Aster incisus is a common flower found in almost all regions of South Korea. In the current study, we investigated the potential antioxidant and anti-inflammatory properties of the Aster incisus methanol extract in LPS-stimulated RAW 264.7 cells. We analyzed the phytochemicals contained in the extract by GC-MS. GC-MS results showed that the Aster incisus extract contains 9 known compounds. Later on, DPPH assay, WST-1 assay, nitric oxide (NO) assay, Western blot, and RT-PCR were conducted to investigate the anti-inflammatory effects of the extract. Our WST-1 assay results revealed that Aster incisus did not affect the viability of all tested cell lines up to a concentration of 200 µg/ml; therefore, lower concentrations (50 µg/ml and 150 µg/ml) were used for further assays. Aster incisus scavenged DPPH and inhibited the production of NO. Aster incisus also reduced significantly the production of inflammation-related enzymes (iNOS, Cox-2) and cytokines (TNFα, IL-1ß, and IL-6) and the gene expression of the proinflammatory cytokines. Additionally, further Western blot results indicated that Aster incisus inhibited the expression of p-PI3K, p-IκBα, p-p65 NF-κB, p-ERK1/2, p-SAPK/JNK, and p-Akt. Our results demonstrated that Aster incisus suppressed the expression of the inflammation mediators through the regulation of NF-κB, MAPK, and Akt pathways.

Anticancer activity of Sasa borealis leaf extract-mediated gold nanoparticles.

Advancements in metal nanoparticle synthesis using plant extracts and their anticancer activity have received significant attention in recent years. The green approach for the synthesis of gold nanoparticles (AuNPs) using leaf extract of Sasa borealis is reported in this study. Synthesis of AuNPs was performed at 50 °C, and nanoparticle formation was observed after 20 min incubation. AuNPs formation was confirmed by the UV-visible spectrum peak at 542 nm. The synthesized AuNPs were oval, spherical with sizes around 10-30 nm observed using the transmission electron microscope. Energy dispersive X-ray analysis was utilized for the detection of elemental compound. The face centered cubic structure was confirmed by X-ray diffraction pattern. The reduction of tetrachloroauric acid into AuNPs by the phytochemical compounds of S. borealis extract was determined by Fourier transform infrared spectroscopy and the presence of biomolecules was studied by GC-MS. The synthesized AuNPs was tested for toxic effect on HEK293 cells and anticancer activity on AGS cells by WST-1® assay. Condensation or fragmentation is a characteristics of apoptosis, which was confirmed by 4,6-diamidino-2-pheynylindole dihydrochoride (DAPI) staining. The S. borealis-mediated AuNPs have good activity as an anticancer agent and it will be beneficial in cancer therapeutics.

Autophagy and Inflammatory Response in the Tumor Microenvironment.

Cell death is the last fate of the life cycle of cells. Different pathways involved in cell death are known to date, and are mostly represented by apoptosis, necrosis, and autophagy. Autophagy is one of the most preserved cell death pathways, characterized by the elimination of large parts of cytoplasmic components after being consumed by a double-membraned vesicle called an autophagosome. The formed autophagosome then fuses with a lysosome containing degrading enzymes and leads to the digestion of the autophagosome content. Autophagy is triggered by stress-related inducers, and is partially dependent on apoptotic proteins. It plays a major role in cancer, particularly in the tumor microenvironment where it has a paradoxical function in acting as a tumor suppressor and also as a tumor promoter. In the tumor microenvironment, autophagy regulates the differentiation of macrophages into tumor-associated macrophages (TAMs) and fibroblasts into cancer-associated fibroblasts (CAFs). TAMs and CAFs are abundantly present in the tumor microenvironment, and participate actively in tumor growth, tumor invasiveness, and tumor resistance to chemotherapy.

Cyperus amuricus induces G1 arrest and apoptosis through endoplasmic reticulum stress and mitochondrial signaling in human hepatocellular carcinoma Hep3B cells.

ETHNOPHARMACOLOGY RELEVANCE: Cyperus amuricus (C. amuricus), belongs to the family Cyperaceae, was used to exert wound healing, diuretic, astringent and other intestinal problems in oriental medicine. However, only a few studies have reported its anticancer activities. AIM OF THE STUDY: In this study, we determined the activity of C. amuricus on ER stress-induced cell death and G1 cell cycle arrest in human hepatocellular carcinoma (HCC) Hep3B cells. MATERIALS AND METHODS: The in vitro cell proliferation assay of C. amuricus was tested on Hep3B and human embryonic kidney HEK293 cells. Subsequently, the cell cycle distribution in the indicated stages using flow cytometric analysis, the expression of cell cycle-related proteins by western blot analysis and immunofluorescence detection of p21CIP1/WAF1 were determined for the comprehensive identification of cell cycle arrest in Hep3B cells. The effect of C. amuricus on the expression of apoptosis-related proteins in Hep3B cells was also performed by western blot analysis. Furthermore, induction of the ER stress mediators in C. amuricus-treated Hep3B cells were observed by western blot analysis, intracellular Ca2+ mobilization assay and immunofluorescence detection of caspase-12. RESULTS: C. amuricus strongly exhibited cytotoxic activity on Hep3B cells, but not on HEK293 cells. C. amuricus affected the phosphorylation levels of endoplasmic reticulum sensors and increased the expression of GRP78/BiP and CHOP, resulting in the accumulation of unfolded proteins in the ER and triggering the unfolded protein response. These changes occurred by the elevation of intracellular Ca2+ concentrations, which contributed to ER stress-induced apoptosis in C. amuricus-treated Hep3B cells. C. amuricus also coordinated the stimulation of ER chaperones, which initiated G1 cell cycle arrest through the induction of CDKIs and the inhibition of cyclins and CDKs. Furthermore, C. amuricus triggered apoptosis through the activation of mitochondrial-dependent pathway in Hep3B cells. CONCLUSIONS: Our results suggest that C. amuricus is an effective apoptosis inducing agent for Hep3B cells via the G1 arrest, ER stress and mitochondrial mediated apoptotic pathways.