No abstract available.
Chemoprevention ; Tuberculosis

No abstract available.
Chemoprevention* ; Head and Neck Neoplasms* ; Head*

Metformin is a first-line anti-diabetic drug that has been widely used in patients with type 2 diabetes. Many population-based epidemiologic studies have shown that metformin treatment is associated with decreased risk for various cancers. Recent epidemiologic studies showed that the use of metformin was associated with a reduction in gastric cancer risk, especially in patients with type 2 diabetes who used metformin for long periods of time (>2~3 years). Currently, there are no registered clinical trials investigating the anti-cancer effect of metformin in gastric cancer; hence, further well-designed clinical trials are required. Herein, we review the literature regarding the use of metformin for the prevention of gastric cancer.
Chemoprevention* ; Epidemiologic Studies ; Humans ; Metformin* ; Stomach Neoplasms*

No abstract available.
*Chemoprevention ; Colorectal Neoplasms/*prevention & control ; *Diet ; Humans

One of the best approaches against cancer is prevention. Inactivation of the p53 or p16INK4a genes has been extensively reported in most human cancer cells. Both p53 and p16INK4a function as tumor suppressors. Therefore, functional restoration of these molecules is considered to be one of the most useful methods for cancer prevention and therapy. We have proposed a concept termed ‘gene-regulating chemoprevention and chemotherapy’ regarding the above pathway. This concept assumes that transcriptional regulation by drugs on tumor-suppressor genes, downstream target genes or functionally similar genes (for example, family genes) of the tumor-suppressor genes would contribute to the prevention of human malignancies. Histone deacetylase (HDAC) inhibitors have been shown to be potent inducers of growth arrest, differentiation and apoptotic cell death. Previously, we demonstrated that HDAC inhibitors, such as sodium butyrate and trichostatin A (TSA), transcriptionally induce the cyclin-dependent kinase inhibitor p21WAF1/Cip1, a downstream target gene of p53, in a p53-independent manner. Furthermore, we have recently shown that HDAC inhibitors activate Gadd45, another downstream target gene of p53, and p19INK4d, a gene functionally similar to p16INK4a. Our results, taken together with previous findings, suggest that HDAC inhibitors may be one of the most attractive and promising agents for ‘gene-regulating chemoprevention’ and ‘molecular-targeting prevention’ of cancer.
Prevention ; Malignant Neoplasms ; Chemoprevention ; inhibitors ; Genes

Background: Administration of chemotherapy to prevent postmolar gestational trophoblastic neoplasia was first implemented in the 1960’s. However, its use has remained controversial. Objectives: This study aimed to describe the effect of chemoprophylaxis in preventing progression of hydatidiform mole to gestational trophoblastic neoplasia among patients managed in a tertiary hospital in Davao City from 2011 to 2015. Materials & Method: This retrospective cross-sectional study evaluated 123 cases of hydatidiform mole who were managed at a tertiary hospital in Davao City from the years 2011 to 2015. The patients’ charts were retrieved to get the clinicodemographic profile, progression to gestational trophoblastic neoplasia, and occurrence of adverse effects secondary to chemoprophylaxis. Patients with rising or plateauing beta human chorionic gonadotropin titer were identified within the 3-year period from molar evacuation. Collected data were analyzed using frequency and percentage distribution. Results: The mean age of the patients was 30.5 years, 24% of whom were noted in women more than 40 years of age. The average age of gestation on admission was 14.89 weeks. All patients had a histopathologic diagnosis of complete mole and at least one risk factor for developing postmolar gestational trophoblastic neoplasia. Patients did not experience any significant side effect to chemoprophylaxis. None of the patients developed gestational trophoblastic neoplasia within the 3-year period of monitoring. Conclusion The administration of chemoprophylaxis to patients diagnosed with hydatidiform mole may be effective against the development of postmolar gestational trophoblastic neoplasia.
Pregnancy ; Female ; Gestational Trophoblastic Disease ; Hydatidiform Mole ; Neoplasms ; Chemoprevention

Neoplasms of the upper gastrointestinal tract are related by location and have distinct clinical and molecular characteristics. Malignancies of the upper gastrointestinal tract are often diagnosed at an advanced stage and are generally associated with a poor patient prognosis. Improved understanding of the molecular biology of these tumors should provide new targets for diagnosis, chemoprevention, and therapy. This review focuses on the molecular biology of esophageal adenocarcinoma, esophageal squamous cell carcinoma and gastric adenocarcinoma. Fundamental principles of carcinogenesis are discussed first, followed by the key similarities and differences of each cancer.
Adenocarcinoma ; Carcinoma, Squamous Cell ; Chemoprevention ; Esophageal Neoplasms ; Gastrointestinal Neoplasms ; Humans ; Molecular Biology ; Prognosis ; Upper Gastrointestinal Tract

PURPOSE: It has been reported that retinoic acid, one of the most popular agents for chemoprevention could inhibit the proliferation of many cancer cells including neuroblastoma and glioblastoma. However, there is increasing demand reaccessing its in vitro inhibitory effect on the tumor proliferation because of the poor results from recent clinical trials of retinoic acid in the malignant brain tumor. Retinoicacid ptomoted the diffferentiation and apoptosis of tumor cell so that its effect might be obvious in the pediatric brain tumor. Therefore we are going to confirm the effectiveness of retinoic acid to inhibit the proliferation of the tumor cells; glioblastoma and medulloblastoma in childhood. METHODS: Medulloblastoma cells were derived from the primary culture of the patient's specimen, and glioblastoma cells were cell lines of 373-MG and 87-MG. We estimated growth inhibition rate of each tumor cells using MTT assay in the concentration from 10 M to 10((-5))M of all-trans and 13-cis retinoic acid. RESULTS: 13-cis retinoic acid in the concentration of 10 6M inhibited cell growth rate 10-22% on the 4th day of incubation, 10% on the 7th day, and 0-12% on the 14th day in the concentration from 10((-6))M to 10((-5))M. All-trans retinoic acid inhibited cell growth rate less than 5% in the concentration less than 10((-5))M though the whole incubation period, but 42% on the 4th day, 37% on the 7th day, and 0% on the 14th day in the concentration of 10((-5))M. 13-cis retinoic acid inhibited cell growth rate 30% on the 4th day, 20% on the 7th and 14th day in the concentration between 10((-6))M and 10((-5))M. Alltrans retinoic acid inhibited cell growth rate less than 5% on the 4th and 7th day. Medulloblastoma cells showed growth inhibition more than 25% by all-trans and 13-cis retinoic acid in the concentration less than 10((-6))M. 13-cis retinoic acid showed 25% growth inhibition in the concentration above 10((-6))M, but all-trans retinoic acid showed 40% growht inhibition in the same concentration. CONCLUSION: We could not find the effect of retinoic acid in the glioblastoma cells due to variable responses of the tumor cell growth inhibition in the concentration of maximum tolerable dose. However, there ia a significant inhibitory effect of medulloblastoma cell proliferation both in the 13-cis and all-trans retinoic acid.
Apoptosis ; Brain Neoplasms ; Cell Culture Techniques* ; Cell Line ; Cell Proliferation ; Chemoprevention ; Glioblastoma* ; Isotretinoin* ; Medulloblastoma* ; Neuroblastoma ; Tretinoin

Elevatio of serum transaminase were observed in 17.1% of patients administered isoniazid, and in 30.8% of patients administered isoniazid and rifampicin, from 2 weeks to 10 months after the administration of these drugs. Two cases of symptomatic hepatitis were observed in patients administered isoniazid and rifampicin during the same period. Patients in whom isoniazid was interrupted or rifampicin was replaced to ethambutol showed a return of the serum transaminase level to normal over a variable period of time(from 4 to 8 weeks). Isoniazid was not interrupted in 4 subjects receiving isoniazid only for chemoprophylaxis. In three of these, this reactin was self-limited with spontaneous return of serum transaminase level to normal In this study, sex and age incidence of hepatic dysfunction were not significant. Further study with more large subject group is required to evaluate exact incidence and time of onset of hepatic dysfunction due to isoniazid or rifampicin or both. It was recommended that patient given anti-tuberculous drug therapy should be contacted monthly interval to monitor for possible hepatotoxicity.
Chemoprevention ; Child* ; Drug Therapy ; Ethambutol ; Hepatitis ; Humans ; Incidence ; Isoniazid ; Liver* ; Rifampin

PURPOSE: Allium sativum (AS) has been known to have widespread benefits in reducing some human cancer risk by immune stimualtion and anticarcinogenic activity. In the present study, we evaluated the preventive and antitumor properties of AS as an effective anticancer modifier for human prostate cancer in vivo. MATERIALS AND METHODS: Subcutaneous prostate cancers were established in athymic nude mice with 5x10(5) PC-3 human androgen-indenpendent prostate cancer cells. AS was injected at the site of tumor transplantation on day 1 and one week intervals up to 5 weeks (Experiment I), and into the established tumors sized by 50-60mm(3) weekly for 5 weeks (Experiment II). Therapeutic responses and efficacies of AS for prostate cancers in vivo were determined in separate controlled experiments, and definite histopathological studies were also performed. RESULTS: In vivo studies indicated statistically significant reduction in the incidence of tumor formation with programmed and continuous AS intralesional treatment. For established prostate cancer, AS treatment also demonstrated an inhibitory effect of tumor growth compared with control. Histomorphological and immunohistochemical studies demonstrated marked apoptosis after 5 weeks-AS continuous treatment in Experiment II. CONCLUSIONS: AS had a definite antitumor activity to inhibit tumorigenesis and may modulate tumor growth of prostate cancer in vivo. It is non-toxic, readily avaliable and inexpensive. AS, in the future, may be developed as a novel and effective treatment in chemoprevention for human prostate cancer.
Allium* ; Animals ; Apoptosis ; Carcinogenesis ; Chemoprevention ; Garlic ; Growth and Development* ; Humans ; Incidence ; Mice ; Mice, Nude ; Prostate* ; Prostatic Neoplasms*