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

A number of naturally-occurring or synthetic chemicals have been reported to exhibit prostate chemopreventive effects. Synthetic 5alpha-reductase (5-AR) inhibitors, e.g. finasteride and durasteride, gained special interests as possible prostate chemopreventive agents. Indeed, two large-scale epidemiological studies have demonstrated that finasteride or durasteride significantly reduced the incidence of prostate cancer formation in men. However, these studies have raised an unexpected concern; finasteride and durasteride increased the occurrence of aggressive prostate tumor formation. In the present study, we have observed that treatment of finasteride did not affect the growth of androgen-refractory PC-3 prostate cancer cells. Finasteride also failed to induce apoptosis or affect the expression of proto-oncogenes in PC-3 cells. Interestingly, we found that treatment of finasteride induced the expression of Nrf2 and HO-1 proteins in PC-3 cells. In particular, basal level of Nrf2 protein was higher in androgen-refractory prostate cancer cells, e.g. DU-145 and PC-3 cells, compared with androgen-responsive prostate cancer cells, e.g. LNCaP cells. Also, treatment of finasteride resulted in a selective induction of Nrf2 protein in DU-145 and PC-3 cells, but not in LNCaP cells. In view of the fact that upregulation of Nrf2-mediated phase II cytoprotective enzymes contribute to attenuating tumor promotion in normal cells, but, on the other hand, confers a selective advantage for cancer cells to proliferate and survive against chemical carcinogenesis and other forms of toxicity, we propose that finasteride-mediated induction of Nrf2 protein might be responsible, at least in part, for an increased risk of high-grade prostate tumor formation in men.
Apoptosis ; Carcinogenesis ; Chemoprevention ; Finasteride* ; Hand ; Humans ; Incidence ; Male ; Prostate* ; Prostatic Neoplasms ; Proto-Oncogenes ; Up-Regulation

Genipin, an aglycone derived from geniposide found in Gardenia jasminoides, is known to be an excellent natural cross-linker, strong apoptosis inducer, and antiviral agent. Although evidence suggests antiviral activity of genipin in several in vitro viral infection systems, there have been few literatures which review antitumor effects of genipin in a variety of in vitro/in vivo models of cancers yet. In this review, we present some of the latest findings in the studies of genipin focusing on antitumor effects and its mechanisms. In brief, genipin inhibits mitochondrial uncoupling protein 2 to increase accumulation of reactive oxygen species, leading to ROS/c-Jun N-terminal kinase-dependent apoptosis of cancer cells. Genipin also increase tissue inhibitors of metalloproteases (MMP), resulting to decrease activities of MMP-2 which plays a key role in metastasis of cancers. Genipin has shown a biphasic effects on cell death and survival in cancer cells as many other plant-derived phytochemicals do. Finally we discuss the potential of genipin as a promosing novel antitumor agent which could be applicable to chemotherapy and/or chemoprevention for cancers.
Apoptosis ; Cell Death ; Chemoprevention ; Drug Therapy ; Gardenia ; In Vitro Techniques ; Metalloproteases ; Neoplasm Metastasis ; Phytochemicals ; Reactive Oxygen Species

Despite advance in detection and management of prostate cancer, this disease remains a major cause of morbidity and mortality in men. Increasing attention has focused on the role of chemoprevention for prostate cancer, ie the administration of agents that inhibit one or more steps in the natural history of prostate carcinogenesis. Chemoprevention of prostate cancer is currently being tested in a wide range of clinical trials, and have focused on the role of dietary factors, vitamins and trace elements in prostate cancer. These studies have the potential to fundamentally alter the current approach to prostate cancer management. The current status of clinical trials investigating the use of interventions designed to reduce the risk of prostate cancer is reviewed.
Carcinogenesis ; Chemoprevention* ; Humans ; Male ; Mortality ; Natural History ; Prostate ; Prostatic Neoplasms ; Trace Elements ; Vitamins

Imaging mass spectrometry (IMS) is currently receiving large attention from the mass spectrometric community, although its use is not yet well known in the clinic. As matrix-assisted laser desorption/ionization time-of-flight (MALDI)-IMS can show the biomolecular changes in cells as well as tissues, it can be an ideal tool for biomedical diagnostics as well as the molecular diagnosis of clinical specimens, especially aimed at the prompt detection of premalignant lesions much earlier before overt mass formation, or for obtaining histologic clues from endoscopic biopsy. Besides its use for pathologic diagnosis, MALDI-IMS is also a powerful tool for the detection and localization of drugs, proteins, and lipids in tissue. Measurement of parameters that define and control the implications, challenges, and opportunities associated with the application of IMS to biomedical tissue studies might be feasible through a deep understanding of mass spectrometry. In this focused review series, new insights into the molecular processes relevant to IMS as well as other field applications are introduced.
Biopsy ; Chemoprevention ; Diagnosis ; Mass Spectrometry* ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; Biomarkers