• Asian Pacific Journal of Cancer Prevention
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• v.13 no.2
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• pp.427-436
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• 2012

Targeted therapy has been a very promising strategy of drug development research. Many molecular mechanims of diseases have been known to be regulated by abundance of proteins, such as receptors and hormones. Chemoprevention for treatment and prevention of diseases are continuously developed. Pre-clinical and clinical studies in chemoprevention field yielded many valuable data in preventing the onset of disease and suppressing the progress of their growth, making chemoprevention a challenging and a very rational strategy in future researches. Natural products being rich of flavonoids are those fruits belong to the genus citrus. Ethanolic extract of Citrus reticulata and Citrus aurantiifolia peels showed anticarcinogenic, antiproliferative, co-chemotherapeutic and estrogenic effects. Several examples of citrus flavonoids that are potential as chemotherapeutic agents are tangeretin, nobiletin, hesperetin, hesperidin, naringenin, and naringin. Those flavonoids have been shown to possess inhibition activity on certain cancer cells' growth through various mechanisms. Moreover, citrus flavonoids also perform promising effect in combination with several chemotherapeutic agents against the growth of cancer cells. Some mechanisms involved in those activities are through cell cycle modulation, antiangiogenic effect, and apoptosis induction.Previous studies showed that tangeretin suppressed the growth of T47D breast cancer cells by inhibiting ERK phosphorylation. While in combination with tamoxifen, doxorubicin, and 5-FU, respectively, it was proven to be synergist on several cancer cells. Hesperidin and naringenin increased cytotoxicitity of doxorubicin on MCF-7 cells and HeLa cells. Besides, citrus flavonoids also performed estrogenic effect in vivo. One example is hesperidin having the ability to decrease the concentration of serum and hepatic lipid and reduce osteoporosis of ovariectomized rats. Those studies showed the great potential of citrus fruits as natural product to be developed as not only the source of co-chemotherapeutic agents, but also phyto-estrogens. Therefore, further study needs to be conducted to explore the potential of citrus fruits in overcoming cancer.

• Journal of Digestive Cancer Reports
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• v.8 no.2
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• pp.97-101
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• 2020

Metformin is a widely used first-line anti-diabetic drug worldwide. Epidemiologic studies using the large population-based cohort database have shown the association between metformin uses and reduced risk of various type cancers including gastric cancer. In the gastric cancer prevention, metformin use was associated with the significant reduction of gastric cancer risk, especially for long-term metformin users. However, there is no well-designed randomized controlled clinical trial investigating the effect of metformin as a chemopreventive drug for gastric cancer. Therefore, further well-designed clinical trials will be needed to implement metformin for chemoprevention of gastric cancer.

• Korean Journal of Pharmacognosy
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• v.38 no.1
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• pp.62-66
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• 2007

Ethanol extract from Salvia miltiorrhiza (SME) was tested for breast cancer chemoprevention and metastasis by measuring the activites of cytochrome P45O 1A1, aromatase, ornithine decarboxylase (ODC), and matrix metalloproteinase (MMP)-9. SME significantly inhibited cytochrome P45O 1A1-mediated ethoxyresorufin O-deethylase (EROD) activity in a dose-dependent manner in a concentration range of 100${\sim}$l,200 ${\mu}g/ml$ (p<0.01). Microsomal aromatase (estrogen synthase) activity was suppressed 54.9%${\sim}$77.5% by the SME at concentration of 600${\sim}$l,200 ${\mu}g/ml$. ODC activity induced by 12-O-tet-radecanoylphorbol-13-acetate (TPA) was significantly reduced by the SME 900 and 1,200 ${\mu}g/ml$ (p<0.05) in MCF-7 breast cancer cells. In addition, SME (900 and 1,200 ${\mu}g/ml$) markedly inhibited MMP-9 activity, a key role in cancer metastasis. Therefore, SME is worth further investigation with respect to breast cancer chemoprevention or therapy.

• Journal of Digestive Cancer Research
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• v.11 no.1
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• pp.9-14
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• 2023

The prevalence of Barrett's esophagus is increasing in South Korea. Several strategies have been tried to prevent its progression to esophageal adenocarcinoma. It is questionable whether the strategies being tried in the West can be applied adequately in South Korea. However, despite the incidence of esophageal adenocarcinoma in the West, which is considerably higher than that in South Korea, the incidence of high-grade dysplasia/esophageal adenocarcinoma in population-based studies is as low as 0.23%/person-year. Therefore, in Korea, where the prevalence is lower than that, it is necessary to select high-risk groups more carefully for chemoprevention. The age of onset of gastroesophageal reflux disease-like symptoms at least once a week is related to the high-risk group rather than the presence or absence of chronic gastroesophageal reflux symptoms. The risk factors for esophageal adenocarcinoma include the patient's sex, age, smoking habit, and obesity. Proton pump inhibitors have a better preventive effect against esophageal adenocarcinoma compared to H2-receptor blockers, but their application to patients in Korea is limited due to the high number of individuals in need of treatment. Therefore, while considering the risk factors for the progression of esophageal adenocarcinoma, the administration of proton pump inhibitors should be considered for gastroesophageal reflux disease.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.161-167
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• 2000

Methanol extract and its fractions of Polyozellus multiplex inhibited the growth of several tumor cell lines and its water fraction showed a higher cytotoxicity effect on the human gastric carcinoma cell, SNU668 than on the other cell lines. The glutathione S-transferase (GSH) content was decreased by MNNG treatment but increased by adding Polyozellus multiplex water fractions. Also the activities of GSH and superoxide dismutase were increased by more the treatment of Polyozellus multiplex water fractions than by N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) alone. Polyzellus multiplex water fraction cased significant reduction in the proliferating cell unclear antigen (PCNA) labelling index in the glandular stomach epithelium as compared with the value of MNNG alone.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.11-12
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• 2001

Selenium is known to have both chemopreventive and therapeutic benefits of cancer. Recent studies have implicated that apoptosis is one of the most plausible mechanism of chemopreventive effects of selenium compounds and tumor invasion is a new factor involved in chemotherapy. In the present study, we demonstrate that Se-methylselenocysteine(MSC), one of the most effective selenium compound sat chemoprevention, induces apoptosis in HL-60 cells and that ROS plays a crucial role in MSC-induced apoptosis.(omitted)

• Journal of Digestive Cancer Reports
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• v.8 no.2
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• pp.77-80
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• 2020

Gastric cancer is one of the leading causes of cancer-related deaths worldwide. The increased expression of cyclooxygenase (COX)-2 has been implicated in the development and progression of gastric cancers. A number of recent studies have been published evaluating the chemopreventive effect of aspirin and non steroidal anti inflammatory drungs (NSAIDs) against gastric cancer. Aspirin and NSAIDs use may reduce the risk of gastric cancer incidence and death, whereas other studies have reported contradictory results. Therefore, further study should be needed to clarify the role of aspirin and NSAIDs in the chemoprevention of gastric cancer.

• Food Science and Preservation
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• v.8 no.2
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• pp.213-216
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• 2001

Chemoprevetive effect of Saururus Chinensis (Lour.) Bail water extract on several tumor cells and Chinese hamster V79 cells were investigated. The water extracts of Saururus Chinensis (Lour.) Bail showed a higher cytotoxicity effect on the human histiocytic leukemia cells(U937) and protective effects against the cytotoxicity of H$_2$O$_2$. These results suggest that Saururus Chinensis (Lour.) Bail may useful as potential soures of chemopreventive and antioxidative agents.

• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2001.10b
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• pp.11-12
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• 2001

• Korean Journal of Pharmacognosy
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• v.35 no.4 s.139
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• pp.283-287
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• 2004

The effect of water extract from Cnidii Rhizoma (CRW) on proliferation of human breast cancer cells, nitric oxide production, nitric oxide synthase expression, and ornithine decarboxylase activity was tested. CRW inhibited the growth of both estrogen-dependent MCF-7 and estrogen-independent MDA-MB-23I human breast cancer cells. Lipopolysaccharide-induced nitric oxide (NO) production was significantly reduced by CRW at the concentration of 0.5, 1.0 and 5.0 mg/ml. Expression of inducible nitric oxide synthase (iNOS) was also suppressed with the treatment of CRW in Raw 264.7 cells. CRW inhibited induction of ornithine decarboxylase by 12-0-tetradecanoylphorbol-13-acetate, a key enzyme of polyamine biosynthesis, which is enhanced in tumour promotion. Therefore, CRW is worth further investigation with respect to breast cancer chemoprevention or therapy.