Inhibitory effect of phytoglycoprotein (38 kDa) on expression of matrix metalloproteinase-9 in 12-O-tetradecanoylphorbol-13-acetate-treated HepG2cells

Chemical Constituents and Their Biological Activities from Genus Styrax

Plants from the genus Styrax have been extensively used in folk medicines to treat diseases such as skin diseases and peptic ulcers and as an antiseptic and analgesic. Most Styrax species, especially Styrax tonkinensis, which is used as an expectorant, antiseptic, and analgesic in Chinese traditional medicine, could screen resin after external injury. Styrax is also used in folk medicines in Korea to treat sore throat, bronchitis, cough, expectoration, paralysis, laryngitis, and inflammation. Different parts of various Styrax species can be widely employed for ethnopharmacological applications. Moreover, for ethnopharmacological use, these parts of Styrax species can be applied in combination with other folk medicines. Styrax species consist of versatile natural compounds, with some of them exhibiting particularly excellent pharmacological activities, such as cytotoxic, acetylcholinesterase inhibitory, antioxidant, and antifungal activities. Altogether, these exciting results indicate that a comprehensive review of plants belonging to this genus is essential for helping researchers to continuously conduct an in-depth investigation. In this review, the traditional uses, phytochemistry, corresponding pharmacological activities, and structure-activity relationships of different Styrax species are clarified and critically discussed. More insights into potential opportunities for future research are carefully assessed.

PM2.5, Fine Particulate Matter: A Novel Player in the Epithelial-Mesenchymal Transition?

Epithelial-mesenchymal transition (EMT) refers to the conversion of epithelial cells to mesenchymal phenotype, which endows the epithelial cells with enhanced migration, invasion, and extracellular matrix production abilities. These characteristics link EMT with the pathogenesis of organ fibrosis and cancer progression. Recent studies have preliminarily established that fine particulate matter with an aerodynamic diameter of less than 2.5 μm (PM_2.5) is correlated with EMT initiation. In this pathological process, PM_2.5 particles, excessive reactive oxygen species (ROS) derived from PM_2.5, and certain components in PM_2.5, such as ions and polyaromatic hydrocarbons (PAHs), have been implicated as potential EMT mediators that are linked to the activation of transforming growth factor β (TGF-β)/SMADs, NF-κB, growth factor (GF)/extracellular signal-regulated protein kinase (ERK), GF/phosphatidylinositol 3-kinase (PI3K)/Akt, wingless/integrated (Wnt)/β-catenin, Notch, Hedgehog, high mobility group box B1 (HMGB1)-receptor for advanced glycation end-products (RAGE), and aryl hydrocarbon receptor (AHR) signaling cascades and to cytoskeleton rearrangement. These pathways directly and indirectly transduce pro-EMT signals that regulate EMT-related gene expression in epithelial cells, finally inducing the characteristic alterations in morphology and functions of epithelia. In addition, novel associations between autophagy, ATP citrate lyase (ACLY), and exosomes with PM_2.5-induced EMT have also been summarized. However, some debates and paradoxes remain to be consolidated. This review discusses the potential molecular mechanisms underlying PM_2.5-induced EMT, which might account for the latent role of PM_2.5 in cancer progression and fibrogenesis.

Anti-invasion and anti-metastasis effects of Valjatrate E via reduction of matrix metalloproteinases expression and suppression of MAPK/ERK signaling pathway

Valjatrate E is an iridoid compound extracted from Valeriana jatamansi Jones herb and is the active ingredient in antitumor activity. Here, we reported its action on tumor invasion and metastasis in the human hepatocellular carcinoma HepG2, aiming at a better understanding of the potential mechanism of action of Valjatrate E. HepG2 cells were treated with Valjatrate E at different concentrations. Wound healing assay and transwell chamber assay were used to determine the effects of Valjatrate E on the migration and invasiveness of HepG2 cells, respectively. Moreover, homogeneity and heterotypic adhesion experiments evaluated the adhesion property of HepG2 cells. The molecular mechanisms by which Valjatrate E inhibited the invasion and migration of HepG2 cells were investigated by gelatin zymography experiment and western blot. Treatment with Valjatrate E inhibited the migration and invasion of HepG2 cells. It achieved this by reducing the expression of matrix metalloprotease 2 (MMP-2) and matrix metalloprotease 9 (MMP-9), by inhibition of heterogeneous adhesion ability, by blocking mitogen-activated protein kinase (MAPK) signaling via inhibiting the phosphorylation of extracellular signal-regulated kinases (p-ERK). Taken together, these findings provide new evidence that mitogen-activated protein kinase/extracellular signal regulated kinase (MAPK/ERK) signaling pathway plays an important role in promoting invasion and metastasis in HepG2 cells through p-ERK, and MAPK/ERK signaling pathway may be a therapeutic target for tumor.

Inductive effect of phytoglycoprotein (38 kDa) on G₀/G₁ arrest and apoptosis in diethylnitrosamine-treated ICR mice

Promotion in the carcinogenic stage is closely related to the growth and proliferation of liver cancer cells. The purpose of this study was whether Styrax japonicum Siebold & Zuccarini (SJSZ) glycoprotein has preventive effect on the growth of hepatocarcinoma cells in diethylnitrosamine (DEN)-induced ICR mice. The study evaluated cell cycle and the activities of cell cycle-related factors [cyclin D1/cyclin dependent kinase (CDK) 4], cell cycle inhibitors (CKIs; p53, p21, and p27), proliferating cell nuclear antigen (PCNA), cytochrome c, Bid, caspase-3, and caspase-9 in DEN-induced ICR mice by flow cytometry, immunoblot analysis and qRT-PCR. The results showed that SJSZ glycoprotein (10 mg/kg, BW) arrested G(0)/G(1) phase and the activity of cyclin D1/CDK4, PCNA, and Bid. However, it induced activities of CKIs, cytochrome c, caspase-3, and caspase-9. Taken together, this present study suggested that SJSZ glycoprotein might be a potent inhibition of hepatic tumor promotion.

Normalizing effect of SJSZ glycoprotein (38 kDa) on proliferating cell nuclear antigen and interferon-γ in diethylnitrosamine-induced mice splenocytes

One of the immunosuppressive responses when hepatocellular carcinoma (HCC) develops in mammals is defective proliferation in the spleen. The objective of this study was to investigate the protective effect of the Styrax japonica Siebold et al. Zuccarini (SJSZ) glycoprotein on the proliferation of splenocytes induced by diethlynitrosamine (DEN). To assess whether the SJSZ glycoprotein modulates splenocyte proliferation, Balb/c mice were injected intraperitoneally with DEN (50 mg/kg, BW) for 7 weeks. After 7 weeks, the mice were sacrificed, and spleens were isolated. We evaluated [(3) H]-thymidine incorporation, extracellular signal-regulated kinase (ERK), cell cycle-related factors [p53, p21, p27, cyclin D1/cyclin dependent kinase (CDK) 4], proliferating cell nuclear antigen and interferon (IFN)-γ using radiation activity, immunoblot analysis, and the reverse transcription-polymerase chain reaction. The results revealed that the SJSZ glycoprotein (10 mg/kg, BW) increased [(3) H]-thymidine incorporation, ERK phosphorylation, expression levels of cyclin D1/cyclin dependent kinase 4, and IFN-γ. However, the SJSZ glycoprotein decreased levels of p53, p21, and p27. Taken together, these results suggest that the SJSZ glycoprotein inhibited defective splenocyte proliferation induced by DEN.

SJSZ glycoprotein (38 kDa) modulates macrophage type 1/2-related factors at hepatocarcinogenic stage in N-nitrosodiethylamine-treated Balb/c

Macrophage plays critical role for tumor progression: Type 1 (M1) for tumor prevention and type 2 (M2) for promotion in hepatocellular carcinoma. In order to study the chemopreventive effects of the SJSZ glycoprotein (38 kDa) on M1- or M2-related factors, Balb/c was injected intraperitoneally with N-nitrosodiethylamine (DEN; 50 mg/kg, BW) for 7 weeks. After 7 weeks, the mice were sacrificed. After that, peritoneal macrophages were isolated. We evaluated the production of reactive oxygen species (ROS) and nitric oxide (NO), hepatocarcinogenic signals [activities of mitogen-activated associated kinase (MAPKs), inducible nitric oxide synthase (iNOS), nuclear factor (NF)-κB, and signal transducer and activator of transcription (STAT) 6,], cytokines [interleukin (IL)-10, IL-4, IL-12, and interferon (IFN)-γ], and CD163-positive macrophages (M2 polarization) using biochemical methods, immunoblot analysis, qRT-PCR, ELISA, and flow cytometry. The results revealed that the SJSZ glycoprotein (10 mg/kg, BW) inhibits the phosphorylation of MAPKs and expression of NF-κB, pSTAT6, IL-10, and IL-4; and normalizes production of ROS and NO, and expression of iNOS, IL-12, and IFN-γ. Especially, it inhibited CD163-positive macrophages. In conclusion, these results indicated that SJSZ glycoprotein modulates polarization of macrophage type 1 and type 2 at hepatocarcinogenic initial stage in DEN-treated Balb/c. Thus, SJSZ glycoprotein may be useful as one of immunomodulating agents which have to regulate M1- and M2-related factors to prevent tumor progression.

Upsides and downsides of reactive oxygen species for cancer: the roles of reactive oxygen species in tumorigenesis, prevention, and therapy

SIGNIFICANCE

Extensive research during the last quarter century has revealed that reactive oxygen species (ROS) produced in the body, primarily by the mitochondria, play a major role in various cell-signaling pathways. Most risk factors associated with chronic diseases (e.g., cancer), such as stress, tobacco, environmental pollutants, radiation, viral infection, diet, and bacterial infection, interact with cells through the generation of ROS.

RECENT ADVANCES

ROS, in turn, activate various transcription factors (e.g., nuclear factor kappa-light-chain-enhancer of activated B cells [NF-κB], activator protein-1, hypoxia-inducible factor-1α, and signal transducer and activator of transcription 3), resulting in the expression of proteins that control inflammation, cellular transformation, tumor cell survival, tumor cell proliferation and invasion, angiogenesis, and metastasis. Paradoxically, ROS also control the expression of various tumor suppressor genes (p53, Rb, and PTEN). Similarly, γ-radiation and various chemotherapeutic agents used to treat cancer mediate their effects through the production of ROS. Interestingly, ROS have also been implicated in the chemopreventive and anti-tumor action of nutraceuticals derived from fruits, vegetables, spices, and other natural products used in traditional medicine.

CRITICAL ISSUES

These statements suggest both "upside" (cancer-suppressing) and "downside" (cancer-promoting) actions of the ROS. Thus, similar to tumor necrosis factor-α, inflammation, and NF-κB, ROS act as a double-edged sword. This paradox provides a great challenge for researchers whose aim is to exploit ROS stress for the development of cancer therapies.

FUTURE DIRECTIONS

the various mechanisms by which ROS mediate paradoxical effects are discussed in this article. The outstanding questions and future directions raised by our current understanding are discussed.

SJSZ glycoprotein (38kDa) prevents thymus atrophy and enhances expression of IL-2 and IL-12 in diethylnitrosamine-induced hepatocarcinogenesis

Hepatocellular carcinoma (HCC) is a typical inflammation-associated cancer, but has also been shown to provoke antitumor immune responses. Polarized T helper type 2 (Th2) responses down-regulate antitumor immunity to link with HCC. The objective of this study was to investigate the protective effect of the Styrax japonica Siebold et al. Zuccarini (SJSZ) glycoprotein on thymus atrophy and differential response of Th1/Th2 cells induced by diethlynitrosamine (DEN). To evaluate the modulatory effect of the SJSZ glycoprotein on thymic atrophy and imbalanced Th1/Th2 cells, we examined the weight of the thymus, [(3)H]-thymidine incorporation and expression of proliferating cell nuclear antigen (PCNA), and activities of protein kinase C (PKC)/intracellular Ca(2+), extracellular signal-regulated kinase (ERK)1/2, p38 MAPK, T-box transcription factor (T-bet), GATA-binding protein-3 (GATA-3), cytokines [interleukin (IL)-4, -10, -2, -12 and interferon (IFN)-γ] using radioactivity, immunoblot analysis, and qRT-PCR. The SJSZ glycoprotein (10mg/kg, BW) was shown to increase the weight of the thymus, [(3)H]-thymidine incorporation and PCNA in thymocytes induced by DEN. Also, it increased expression levels of T-bet and Th1 cytokines (IFN-γ, IL-2 and IL-12). However, the activity of PKC/intracellular Ca(2+), phosphorylation of ERK and p38 MAPK, expression levels of GATA-3 and Th2 cytokines (IL-4 and IL-10) were decreased. Taken together, these results suggest that the SJSZ glycoprotein can prevent thymic atrophy and Th2 cytokines induced by DEN.

Inhibitory effect of Styrax Japonica Siebold et al. Zuccarini glycoprotein (38 kDa) on interleukin-1β and induction proteins in chromium(VI)-treated BNL CL.2 cells

Chromium(VI) [Cr(VI)] induces chronic inflammation in hepatocytes. Inflammation has been shown to play an important role in tumorigenesis, tumor progression, and metastasis. To examine the effects of the Styrax Japonica Siebold et al. Zuccarini (SJSZ) glycoprotein on inflammation in BNL CL.2 cells, we evaluated the activities of c-Jun NH(2)-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), nuclear factor (NF)-κB (p50 and p65), and inflammation-related factors [cyclooxygenase (COX)-2, inducible nitric oxide syntheses (iNOS) and interleukin (IL)-1β] in Cr-induced BNL CL.2 cells using immunoblot analysis and RT-PCR. We also used two-dimensional gel electrophoresis (2-DE) to compare between treatments. To determine which proteins are induced by Cr(VI), we evaluated total protein lysates using 2-DE. After Cr(VI) treatment, total protein lysates were prepared and resolved by 2-DE. The results obtained from this study demonstrated that the SJSZ glycoprotein (50 μg/ml) inhibits expression of JNK, ERK, NF-κB, and the expression of COX-2, iNOS, and IL-1β. Moreover, the results obtained from 2DE showed that four proteins out of nine proteins were relatively expressed strongly, while the rest of them were relatively appeared weakly on the gel. Taken together, these data indicate that the SJSZ glycoprotein prevents expression of COX-2, iNOS, and IL-1β by blocking NF-κB and MAPKs in Cr(VI)-induced BNL CL.2 cells.

Activity of tumor necrosis factor-α blocked by phytoglycoprotein (38 kDa) at initiation stage in N-nitrosodiethylamine-induced ICR mice

Hepatocellular carcinoma is becoming one of the most prominent types of cancer in the world. Recently, from Styrax japonica Siebold et al. Zuccarini (SJSZ), we isolated a glycoprotein which consists of carbohydrate moiety (52.64%) and protein moiety (42.35%). We evaluated whether SJSZ glycoprotein prevents hepatocarcinogenesis induced by N-nitrosodiethylamine (DEN). The purpose of this study was to evaluate the effect of SJSZ glycoprotein in DEN-induced hepatocarcinogenesis in ICR mice. To know chemopreventive effect of SJSZ glycoprotein on hepatocarcinogenesis, ICR mice were intraperitoneally injected with N-nitrosodiethylamine (DEN, 10 mg/kg) for 7 weeks. After sacrifice, we evaluated indicators of liver tissue damage [the activities of lactate dehydrogenase (LDH) and alanine aminotransferase (ALT), and thiobarbituric acid reactive substances (TBARS)], antioxidative enzymes [activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)], and initiating hepatocarcinogenic indicator [heat shock protein (HSP) 27 and 70] and hepatocarcinogenic signals [protein kinase C (PKC), extracellular signal-regulating kinase (ERK) 1/2, nuclear factor (NF)-κB (p50 and p65) and tumor necrosis factor-α (TNF-α)] using biochemical methods, immunoblot analysis, and RT-PCR. The results obtained from this study revealed that SJSZ glycoprotein (10 mg/kg, BW) decreased the levels of LDH, ALT, and TBARS, whereas the activities of SOD, GPx, and CAT increased in the DEN-induced ICR mice. With respect to the hepatocarcinogenic indicator and hepatocarcinogenic signals, HSP27, HSP70, PKC, ERK1/2, NF-κB (p50 and p65), and TNF-α, activity decreased. Hence, SJSZ glycoprotein might prevent expression of HSP27 and HSP70 by DEN.