• Biomolecules & Therapeutics
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• v.15 no.3
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• pp.145-149
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• 2007

We have previously shown that 2,4,3',5'-tetramethoxystilbene (TMS), a synthetic trans-stilbene analogue acting as a potent inhibitor of human cytochrome P450 1B1, induces apoptotic cell death in human cancer cells. In the present studies, we report the mechanisms of apoptotic cell death by TMS in human promyelocytic leukemic HL-60 cells. We found that treatment of HL-60 cells with TMS suppressed the cell growth in a concentration-dependent manner with $IC_{50}$ value of about 0.8 ${\mu}M$. Immunoblot experiments revealed that DMHS-induced apoptosis was associated with cleavage of poly (ADP-ribose) polymerase. The release of cytochrome c from mitochondria into the cytosol was significantly increased in response to TMS. TMS caused activation of caspase-3 in a concentration-dependent manner and TMS-mediated caspase-3 activation was partially prevented by the caspase inhibitor, zVAD-fmk. Interestingly, we found that the cytotoxic effect of anticancer drugs such as paclitaxel, docetaxel, or etoposide was enhanced in the presence of TMS. Simultaneous treatment with TCDD also significantly increased cytotoxic effects of TMS alone or TMS and anti-cancer agents. Taken together, our present results indicated that TMS leads to apoptotic cell death in HL-60 cells through activation of caspase-3 activity and release of cytochrome c into cytosol. The ability of TMS to increase cytotoxic effect of anticancer drugs may contribute to its usefulness for cancer chemotherapy.

• Journal of Ginseng Research
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• v.40 no.4
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• pp.431-436
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• 2016

Background: Although numerous studies of the anticancer activities of Korean Red Ginseng (KRG) have been performed, the therapeutic effect of KRG on leukemia has not been fully elucidated. In this study, we investigated the antileukemia activities of KRG and its cellular and molecular mechanisms. Methods: An established leukemia tumor model induced by xenografted T cell lymphoma (RMA cells) was used to test the therapeutic activity of KRG water extract (KRG-WE). Direct cytotoxic activity of KRG-WE was confirmed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The immunomodulatory activities of KRG-WE were verified by immunohistochemistry, nitric oxide production assay. The inhibitory effect of KRG-WE on cell survival signaling was also examined. Results: Orally administered KRG-WE reduced the sizes of tumor masses. Levels of apoptosis regulatory enzymes and cleaved forms of caspases-3 and -8 were increased by this extract. In addition, expression of matrix metalloproteinase-9, a metastasis regulatory enzyme, was decreased by KRG-WE treatment. The proportion of CD11c+ cells was remarkably increased in the KRG-treated group compared to the control group. However, KRG-WE did not show significant direct cytotoxicity against RMA cells. Conclusion: Our results strongly suggest that the KRG might have antileukemia activity through CD11c+ cell-mediated antitumor immunity.

• YAKHAK HOEJI
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• v.47 no.2
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• pp.57-68
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• 2003

Under the active search for biologically active novel agents for cancer prevention and treatment, some agents have been found from plants which are easily available. Our previous research on them revealed that C. annuum L. var. angulosum Mill have high antiproliferating effect on cancer cells. However, it has not been known whether the anticancer efficacy is different according to each part of C. annuum L. var. angulosum Mill or whether it can be changed by timing of harvest or solvent for extraction. Thus we compared the efficacy of each part of C. annuum L. var. angulosum Mill and assessed how much difference in the efficacy can be made according to the time of harvest or solvents for extraction. We observed the morphologic change and apoptosis 48 hr after treatment with the extract of each part of C. annuum L. var. angulosum Mill in MCF-7 mammary gland adenocarcinoma cells and human hepatoma cells. We also counted cancer cells by trypan blue method and MTT method to check the cytotoxicity. The leaf extract showed the highest anticancer effect among all the parts of C. annuum L. var. angulosum Mill; 50％ and 70％ reduction in the number of cancer cells was observed at 25 $\mu\textrm{g}$/mι and 50 $\mu\textrm{g}$/mι, respectively. It was more than 2 times as potent as 5-fluorouracil (5-FU). We found chromosomal fragmentation, clumping, and destuction by PI staining, and DNA fragmentation by electrophoresis. In conclusion, this study suggests that leaf extraction using water as solvent has the highest antiproliferative and apoptotic activity in cancer cells compared with other parts of extraction.

• Journal of Pharmacopuncture
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• v.19 no.3
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• pp.213-224
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• 2016

Objectives: Ginseng Rh2+ is enzyme-treated ginseng extract containing high amounts of converted ginsenosides, such as compound k, Rh2, Rg3, which have potent anticancer activity. We conducted general and genetic toxicity tests to evaluate the safety of ginseng Rh2+. Methods: An acute oral toxicity test was performed at a high-level dose of 4,000 mg/kg/day in Sprague-Dawley (SD) rats. A 14-day range-finding study was also conducted to set dose levels for the 90-day study. A subchronic 90-day toxicity study was performed at dose levels of 1,000 and 2,000 mg/kg/day to investigate the no-observed-adverse-effect level (NOAEL) of ginseng Rh2+ and target organs. To identify the mutagenic potential of ginseng Rh2+, we conducted a bacterial reverse mutation test (Ames test) using amino-acid-requiring strains of Salmonella typhimurium and Escherichia coli (E. coli), a chromosome aberration test with Chinese hamster lung (CHL) cells, and an in vivo micronucleus test using ICR mice bone marrow as recommended by the Korean Ministry of Food and Drug Safety. Results: According to the results of the acute oral toxicity study, the approximate lethal dose (ALD) of ginseng Rh2+ was estimated to be higher than 4,000 mg/kg. For the 90-day study, no toxicological effect of ginseng Rh2+ was observed in body-weight changes, food consumption, clinical signs, organ weights, histopathology, ophthalmology, and clinical pathology. The NOAEL of ginseng Rh2+ was established to be 2,000 mg/kg/day, and no target organ was found in this test. In addition, no evidence of mutagenicity was found either on the in vitro genotoxicity tests, including the Ames test and the chromosome aberration test, or on the in vivo in mice bone marrow micronucleus test. Conclusion: On the basis of our findings, ginseng Rh2+ is a non-toxic material with no genotoxicity. We expect that ginseng Rh2+ may be used as a novel adjuvant anticancer agent that is safe for long-term administration.

• The Korean Journal of Physiology and Pharmacology
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• v.25 no.5
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• pp.479-488
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• 2021

This study aimed to develop docetaxel (DTX) loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (DTX-NPs) and to evaluate the different pharmacological sensitivity of NPs to MCF-7 and MDA-MB-231 breast cancer cells. NPs containing DTX or coumarin-6 were prepared by the nanoprecipitation method using PLGA as a polymer and d-α-tocopherol polyethylene glycol 1000 succinate (TPGS) as a surfactant. The physicochemical properties of NPs were characterized. In vitro anticancer effect and cellular uptake were evaluated in breast cancer cells. The particle size and zeta potential of the DTX-NPs were 160.5 ± 3.0 nm and -26.7 ± 0.46 mV, respectively. The encapsulation efficiency and drug loading were 81.3 ± 1.85% and 10.6 ± 0.24%, respectively. The in vitro release of DTX from the DTX-NPs was sustained at pH 7.4 containing 0.5% Tween 80. The viability of MDA-MB-231 and MCF-7 cells with DTX-NPs was 37.5 ± 0.5% and 30.3 ± 1.13%, respectively. The IC₅₀ values of DTX-NPs were 3.92- and 6.75-fold lower than that of DTX for MDA-MB-231 cells and MCF-7 cells, respectively. The cellular uptake of coumarin-6-loaded PLGA-NPs in MCF-7 cells was significantly higher than that in MDA-MB-231 cells. The pharmacological sensitivity in breast cancer cells was higher on MCF-7 cells than on MDA-MB-231 cells. In conclusion, we successfully developed DTX-NPs that showed a great potential for the controlled release of DTX. DTX-NPs are an effective formulation for improving anticancer effect in breast cancer cells.

• Journal of Nutrition and Health
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• v.55 no.1
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• pp.47-58
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• 2022

Purpose: Obesity and a high-fat diet (HFD) are risk factors for colorectal cancer. We have previously shown that luteolin (LUT) supplementation in HFD-fed mice markedly inhibits tumor development in chemically induced colon carcinogenesis. In this study, we evaluated the anticancer effect of LUT in the inhibition of cell proliferation in HFD-fed obese mice and HT-29 human colorectal adenocarcinoma cells grown in an adipocyte-derived medium. Methods: C57BL/6 mice were fed a normal diet (ND, 11.69% fat out of total calories consumed, n = 10), HFD (40% fat out of total calories consumed, n = 10), HFD with 0.0025% LUT (n = 10), and HFD with 0.005% LUT (n = 10) and were subjected to azoxymethane-dextran sulfate sodium chemical colon carcinogenesis. All mice were fed the experimental diet for 11 weeks. 3T3-L1 preadipocytes and HT-29 cells were treated with various doses of LUT in an adipocyte-conditioned medium (Ad-CM). Results: The weekly body weight changes in the LUT groups were similar to those in the HFD group; however, the survival rates of the LUT group were higher than those of the HFD group. Impaired crypt integrity of the colonic mucosa in the HFD group was observed to be restored in the LUT group. The colonic expression of proliferating cell nuclear antigen and insulin-like growth factor 1 (IGF-1) receptors were suppressed by the LUT supplementation in the HFD-fed mice. The LUT treatment (10, 20, and 40 µM) inhibited the proliferation and migration of HT-29 cells cultured in Ad-CM in a dose-dependent manner, as well as the differentiation of 3T3-L1 preadipocytes. Conclusion: These results suggest that the anticancer effect of LUT is probably due to the inhibition of IGF-1 signaling and adipogenesis-related cell proliferation in colon cancer cells.

• International Journal of Oral Biology
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• v.47 no.3
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• pp.41-48
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• 2022

Ulva compressa Linnaeus (UCL) is a green algae seaweed that performs photosynthesis and is used as a food material in some Asian regions including Korea. It is known to be the dominant species in copper ion-contaminated seas, and many studies on copper ion resistant mechanisms have been reported. UCL is known to have an excellent antioxidant effect, but limited information is available regarding its other physiological activities. In this study, we investigated the anticancer activity of 30% prethanol extracts of Ulva compressa Linnaeus (30% PeUCL) and the underlying mechanisms of its activity on human FaDu hypopharyngeal squamous carcinoma cells. The 30% PeUCL extracts suppressed FaDu cell viability without affecting normal cells (L929), as determined by MTT and viability assays. Furthermore, the 30% PeUCL extracts induced apoptosis, as determined by DAPI staining. The 30% PeUCL extracts inhibited colony formation effectively as well as wound-healing of FaDu cells, even at noncytotoxic concentrations. In addition, 30% PeUCL extracts induced apoptosis significantly through proteolytic cleavage of caspase-3, -7, and -9, and poly (ADP-ribose) polymerase, and by downregulation of Bcl-2 and upregulation of Bax in FaDu cells, as determined by Western blot analysis. Collectively, these results suggest that the inhibitory effect of 30% PeUCL extracts on the growth of oral cancer cells, colony formation and wound-healing may be mediated by caspase- and mitochondrial-dependent apoptotic pathways in human FaDu hypopharyngeal squamous carcinoma cells. Therefore, 30% PeUCL extracts can be administered as a natural chemotherapeutic drug for the treatment of human oral cancers.

• Journal of Physiology & Pathology in Korean Medicine
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• v.36 no.5
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• pp.175-180
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• 2022

The seeds of Trichosanthes kirilowii (STK) used in traditional Oriental medicine for the treatment of dry cough and constipation have diverse pharmacological activities, including hypolipidemic, antioxidant, immunosuppressive, and anticancer effects. However, the effect of STK on angiogenesis has not been studied yet. In this study, we investigated whether the ethanolic extract of STK (ESTK) can regulate the migration and tube formation of human umbilical vein endothelial cells (HUVECs) and explored the underlying mechanism. Results of transwell assay showed that ESTK treatment dose-dependently suppressed the migration of HUVECs. The conditioned medium collected from H1299 human lung cancer cells was used as a chemoattractant. Our observation suggests that ESTK would inhibit the recruitment of endothelial cells into tumors. In addition, ESTK treatment significantly reduced the tube formation of HUVECs. As a molecular mechanism, we found that vascular endothelial growth factor (VEGF)-induced phosphorylation of VEGF receptor 2 (VEGFR2) was completely blocked by ESTK treatment. The expression of angiogenic factors, including VEGFA, fibroblast growth factor 2 (FGF2), angiopoietin, placental growth factor (PGF), platelet derived growth factor (PDGF), angiogenin, and tumor necrosis factor (TNF)-α, was commonly decreased by ESTK treatment in H1299 cells, indicating that ESTK would reduce the production of angiogenic factors from cancer cells. Taken together, our results clearly demonstrated that ESTK exhibited anti-angiogenic effects in HUVECs, which provides another possible mechanism underlying the anticancer activities of STK.

• IMMUNE NETWORK
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• v.22 no.1
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• pp.3.1-3.21
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• 2022

Cancer is one of the leading causes of death worldwide and the number of cancer patients is expected to continuously increase in the future. Traditional cancer therapies focus on inhibiting cancer growth while largely ignoring the contribution of the immune system in eliminating cancer cells. Recently, better understanding of immunological mechanisms pertaining to cancer progress has led to development of several immunotherapies, which revolutionized cancer treatment. Nonetheless, only a small proportion of cancer patients respond to immunotherapy and maintain a durable response. Among multiple factors contributing to the variability of immunotherapy response rates, commensal microbiota inhabiting patients have been identified as one of the most critical factors determining the success of immunotherapy. The functional diversity of microbiota differentially affects the host immune system and controls the efficacy of immunotherapy in individual cancer patients. Moreover, clinical studies have demonstrated that changing the gut microbiota composition by fecal microbiota transplantation in patients who failed a previous immunotherapy converts them to responders of the same therapy. Consequently, both academic and industrial researchers are putting extensive efforts to identify and develop specific bacteria or bacteria mixtures for cancer immunotherapy. In this review, we will summarize the immunological roles of commensal microbiota in cancer treatment and give specific examples of bacteria that show anticancer effect when administered as a monotherapy or as an adjuvant agent for immunotherapy. We will also list ongoing clinical trials testing the anticancer effect of commensal bacteria.

• Journal of Life Science
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• v.30 no.6
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• pp.501-512
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• 2020

Sasa quelpaertensis Nakai leaf has been used as a folk medicine for the treatment of gastric ulcer, dipsosis, and hematemesis based on its anti-inflammatory, antipyretic, and diuretic characteristics. We have previously reported the procedure for deriving a phytochemical-rich extract (PRE) from S. quelpaertensis and how PRE and its ethyl acetate fraction (EPRE) exhibits an anticancer effect by inducing apoptosis in various gastric cancer cells. To explore the molecular targets involved in this apoptosis, we investigated the mRNA and microRNA profiles of EPRE-treated SNU-16 human gastric cancer cells. In total, 2,875 differentially expressed genes were identified by RNA sequencing, and gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicated that the EPRE-modulated genes are associated with apoptosis, mitogen-activated protein kinase, inflammatory response, tumor necrosis factor signaling, and cancer pathways. Subsequently, protein-protein interaction network analysis confirmed interactions among genes associated with cell death and apoptosis, and 27 differentially expressed microRNAs were identified by further sequencing. Here, GO and KEGG pathway analysis revealed that EPRE modified the expression of microRNAs associated with the cell cycle and cell death, as well as signaling of tropomyosin-receptor-kinase receptor, transforming growth factor-b, nuclear factor kB, and cancer pathways. Taken together, these results provide insight into the mechanisms underlying the anticancer effect of EPRE.