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Thrombin, which plays a crucial role in hemostasis, is also implicated in cancer progression. We investigated the effects of the thrombin-targeting recombinant tyrosine-sulfated madanin-1 on cancer cell behavior and signaling pathways compared with wild-type (WT) madanin-1. We generated recombinant madanin-1 2 sulfation (2S) and madanin-1 WT proteins using E. coli. SKOV3 and MDA-MB-231 cells were treated with purified recombinant proteins with or without thrombin stimulation. Migration and invasion of cells were analyzed by a wound healing assay and transwell assay, respectively. Thrombin markedly increased cell migration and invasion in both SKOV3 and MDA-MB-231 cells, which were significantly suppressed by madanin-1 2S (p p p in vivo validation is required.

Chemokine receptors are generally sulfated at tyrosine residues of the N-terminal region. Tyrosine sulfation of the C-C chemokine receptor type 2 (CCR2) enhances its interaction with the chemokine ligand CCL2. Here, we generated a recombinant sulfated CCR2 peptide trap (mCCR2-S2) and investigated its effects on retinal degeneration in mice. Treatment with mCCR2-S2 reduced choroidal neovascularization (CNV) in a laser-induced CNV mouse model. In NaIO3-injected mice, treatment with mCCR2-S2 increased the outer nuclear layer thickness and rhodopsin expression in the retinas compared to that in mice treated with mCCR2-wild-type or glutathione S-transferase controls. Furthermore, glial fibrillary acidic protein (GFAP) expression and macrophage infiltration were decreased in mCCR2-S2-treated retinas. Recombinant mCCR2-S2 suppressed CNV development and retinal degeneration, possibly by regulating macrophage infiltration. Thus, the sulfated form of the CCR2 peptide trap may be a useful tool for treating patients with retinal degeneration, such as those with age-related macular degeneration and intraocular inflammatory disorders.

Ribosomal protein L9 (RPL9), a component of the 60S subunit for protein synthesis, is upregulated in human colorectal cancer. In the present study, we investigated whether RPL9 gained extraribosomal function during tumorigenesis and whether targeting of RPL9 with small interfering (si) RNA could alter the course of colorectal cancer progression. Our results showed that siRNA knockdown of RPL9 suppresses colorectal cancer (CRC) cell growth and long-term colony formation through an increase in sub-G1 cell population and a strong induction of apoptotic cell death. To obtain insights into the molecular changes in response to RPL9 knockdown, global changes in gene expression were examined using RNA sequencing. It revealed that RPL9-specific knockdown led to dysregulation of 918 genes in HCT116 and 3178 genes in HT29 cells. Among these, 296 genes showed same directional regulation (128 upregulated and 168 downregulated genes) and were considered as a common RPL9 knockdown signature. Particularly, we found through a network analysis that Id-1, which is functionally associated with activation of NF-κB and cell survival, was commonly downregulated. Subsequent western blot analysis affirmed that RPL9 silencing induced the decrease in the levels of Id-1 and phosphorylated IκBα in both HCT116 and HT29 cells. Also, the same condition decreased the levels of PARP-1 and pro-caspase-3, accelerating apoptosis. Furthermore, inhibition of RPL9 expression significantly suppressed the growth of human CRC xenografts in nude mice. These findings indicate that the function of RPL9 is correlated with Id-1/NF-κB signaling axis and suggest that targeting RPL9 could be an attractive option for molecular therapy of colorectal cancer.

Salmonella enterica serovar Typhimurium (hereafter referred to as Salmonella), a virulent pathogen, is known to induce host‑cell death. Using reverse transcription‑quantitative polymerase chain reaction, a 28‑fold increase of microRNA (miR)‑155 expression in RAW 264.7 macrophages was observed following infection with Salmonella for 24 h. This miR‑155 upregulation increased macrophage cell death by up to 40% in 48 h following infection. Western blot analysis revealed that receptor interacting protein 1 (RIP1) and 3 (RIP3) were increased at 18 h following miR‑155 transfection to macrophages, similar to Salmonella infection. In addition, inhibition of RIP1 by pre‑incubating macrophages with necrostatin‑1, a RIP1 specific inhibitor, increased the viability of Salmonella‑infected cells and miR‑155‑transfected cells by up to 20%. The cleavage of poly (adenosine diphosphate‑ribose) polymerase‑1 (PARP‑1) was also enhanced by miR‑155 induction upon Salmonella infection. Therefore, it was suggested that RIP1/3‑induced necroptosis and PARP‑1‑mediated necrosis caused by miR‑155 induction may represent distinct routes of programmed necrotic cell death of Salmonella‑infected macrophages.

In this study, we investigated the anti-inflammatory effects of newly synthesized 4-[(butylsulfinyl)methyl]-1,2-benzenediol (SMBD) in lipopolysaccharide (LPS)-stimulated BV2 microglia and the subsequent signaling events. Following stimulation with LPS, elevated production of nitric oxide (NO) and prostaglandin E2 (PGE2) was detected in BV2 cells, however, SMBD pretreatment inhibited the production of NO and PGE2 through suppressing gene expression of inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2), respectively, at non-toxic concentrations. LPS-stimulated gene expression and production of interleukin (IL)-1β and tumor necrosis factor (TNF)-α were also significantly reduced by SMBD. The anti-inflammatory effects of SMBD were associated with suppression of LPS-induced nuclear translocation of nuclear factor-kappa B (NF-κB), and phosphorylation of mitogen-activated protein kinases (MAPKs) and Akt, a phosphatidylinositol 3-kinase (PI3K) downstream effector. Therefore, the present results demonstrate that SMBD down-regulates inflammatory gene expression by inhibiting the activation of NF-κB through interference with the activation of MAPKs and PI3K/Akt signaling. Taken together, our data suggest that SMBD may have potential to be developed into an effective anti-inflammatory agent.

Purpose Radiation-induced autophagy has been shown to play two different roles, in malignant glioma (MG) cells, cytocidal or cytoprotective. However, neither the role of radiation-induced autophagy for cell death nor the existence of autophagy-induced apoptosis, a well-known cell-death pathway after irradiation, has been verified yet. Materials and Methods We observed both temporal and dose-dependent response patterns of autophagy and apoptosis to radiation in MG cell lines. Additionally, we investigated the role of autophagy in apoptosis through knockdown of autophagy-related proteins. Results Autophagic activity measured by staining of acidic vesicle organelles and Western blotting of LC-3 protein increased in proportion to radiation dose from day 1 to 5 after irradiation. Apoptosis measured by annexin-V staining and Western blotting of cleaved poly(ADP-ribose) polymerase demonstrated relatively late appearance 3 days after irradiation that increased for up to 7 days. Blocking of pan-caspase (Z-VAD-FMK) did not affect apoptosis after irradiation, but silencing of Atg5 effectively reduced radiation-induced autophagy, which decreased apoptosis significantly. Inhibition of autophagy in Atg5 knockdown cells was shown to be beneficial for cell survival. Stable transfection of GFP-LC3 cells was observed after irradiation. Annexin-V was localized in cells bearing GFP-LC3 punctuated spots, indicating autophagy in immunofluorescence. Some of these punctuated GFP-LC3 bearing cells formed conglomerated spots and died in final phase. Conclusion These findings suggest that autophagy appears earlier than apoptosis after irradiation and that a portion of the apoptotic population that appears later is autophagy-dependent. Thus, autophagy is a pathway to cell death after irradiation of MG cells.

Sulforaphane, a naturally occurring isothiocyanate found in cruciferous vegetables, has received a great deal of attention because of its ability to inhibit cell proliferation and induce apoptosis in cancer cells. In this study, we investigated the anticancer activity of sulforaphane in the T24 human bladder cancer line, and explored its molecular mechanism of action. Our results showed that treatment with sulforaphane inhibited cell viability and induced apoptosis in T24 cells in a concentration-dependent manner. Sulforaphane-induced apoptosis was associated with mitochondria dysfunction, cytochrome c release and Bcl-2/Bax dysregulation. Furthermore, the increased activity of caspase-9 and -3, but not caspase-8, was accompanied by the cleavage of poly ADP-ribose polymerase, indicating the involvement of the mitochondria-mediated intrinsic apoptotic pathway. Concomitant with these changes, sulforaphane triggered reactive oxygen species (ROS) generation, which, along with the blockage of sulforaphane-induced loss of mitochondrial membrane potential and apoptosis, was strongly attenuated by the ROS scavenger N-acetyl-L-cysteine. Furthermore, sulforaphane was observed to activate endoplasmic reticulum (ER) stress and the nuclear factor-E2-related factor-2 (Nrf2) signaling pathway, as demonstrated by the upregulation of ER stress‑related proteins, including glucose-regulated protein 78 and C/EBP-homologous protein, and the accumulation of phosphorylated Nrf2 proteins in the nucleus and induction of heme oxygenase-1 expression, respectively. Taken together, these results demonstrate that sulforaphane has antitumor effects against bladder cancer cells through an ROS-mediated intrinsic apoptotic pathway, and suggest that ER stress and Nrf2 may represent strategic targets for sulforaphane-induced apoptosis.

We investigated the protective ability of 3-(4'-hydroxyl-3',5'-dimethoxyphenyl)propionic acid (HDMPPA), an active principle in Korean cabbage kimchi, against the production of proinflammatory mediators and cytokines, and the mechanisms involved in lipopolysaccharide (LPS)-stimulated BV2 microglial cells. HDMPPA significantly suppressed the production of nitric oxide (NO) and prostaglandin E2, along with the expression of inducible NO synthase and cyclooxygenase-2 in LPS-stimulated BV2 cells, at concentrations with no cytotoxicity. HDMPPA also attenuated the LPS-induced expression and secretion of proinflammatory cytokines, such as tumor necrosis factor-α and interleukin-1β. Furthermore, HDMPPA inhibited LPS-induced nuclear factor-κB (NF-κB) activation, which was associated with the abrogation of IκB-α degradation and phosphorylation, and subsequent decreases in NF-κB p65 levels. Moreover, the phosphorylation of mitogen-activated protein kinases (MAPKs) and Akt, a downstream molecule of phosphatidylinositol-3-kinase (PI3K), in LPS-stimulated BV2 cells was suppressed markedly by HDMPPA. This effect was associated with a significant reduction in the formation of intracellular reactive oxygen species. The findings in this study suggest that HDMPPA may exert anti-inflammatory responses by suppressing LPS-induced expression of proinflammatory mediators and cytokines through blockage of NF-κB, MAPKs, and PI3K/Akt signaling pathways and oxidative stress in microglia.