Postdiagnostic use of ß-blockers and other antihypertensive drugs and the risk of recurrence and mortality in head and neck cancer patients: an observational study of 10,414 person-years of follow-up.

INTRODUCTION: Growing evidence indicates that norepinephrine promotes cancer growth and metastasis whereas ß-blockers decrease these risks. This study aimed to examine the clinical impact of ß-blockers and other hypertensive drugs on disease recurrence and survival in patients with head and neck squamous cell carcinoma (HNSCC). MATERIALS AND METHODS: This study analyzed a cohort of 1274 consecutive patients who received definitive treatments for previously untreated HNSCC at our tertiary referral center between January 2001 and December 2012. Antihypertensive use was considered positive if patients were on medication from HNSCC diagnosis to at least 1 year after treatment initiation. Cox proportional hazard models were utilized to determine associations between antihypertensive drugs and recurrence, survival, and second primary cancer (SPC) occurrence. RESULTS: Hypertension itself was not a significant variable of recurrence and survival and no antihypertensive drug use affected SPC occurrence (all P > 0.1). After controlling for clinical factors, calcium-channel blocker use remained an independent variable for index cancer recurrence, and ß-blocker use was significantly associated with poor cancer-specific mortality, competing mortality, and all-cause mortality (all P < 0.05). ß-blocker use significantly affected competing and all-cause mortalities in normotensive patients, and calcium-channel blocker use affected index cancer recurrence in normotensive patients (all P < 0.05). CONCLUSIONS: Our data show that ß-blocker use is associated with decreased survival and calcium-channel blockers is associated with increased cancer recurrence in patients of HNSCC.

PPARγ induces growth inhibition and apoptosis through upregulation of insulin-like growth factor-binding protein-3 in gastric cancer cells

Peroxisome proliferator activator receptor-gamma (PPARγ) is a ligand-activated transcriptional factor involved in the carcinogenesis of various cancers. Insulin-like growth factor-binding protein-3 (IGFBP-3) is a tumor suppressor gene that has anti-apoptotic activity. The purpose of this study was to investigate the anticancer mechanism of PPARγ with respect to IGFBP-3. PPARγ was overexpressed in SNU-668 gastric cancer cells using an adenovirus gene transfer system. The cells in which PPARγ was overexpressed exhibited growth inhibition, induction of apoptosis, and a significant increase in IGFBP-3 expression. We investigated the underlying molecular mechanisms of PPARγ in SNU-668 cells using an IGFBP-3 promoter/luciferase reporter system. Luciferase activity was increased up to 15-fold in PPARγ transfected cells, suggesting that PPARγ may directly interact with IGFBP-3 promoter to induce its expression. Deletion analysis of the IGFBP-3 promoter showed that luciferase activity was markedly reduced in cells without putative p53-binding sites (-Δ1755, -Δ1795). This suggests that the critical PPARγ-response region is located within the p53-binding region of the IGFBP-3 promoter. We further demonstrated an increase in PPARγ-induced luciferase activity even in cells treated with siRNA to silence p53 expression. Taken together, these data suggest that PPARγ exhibits its anticancer effect by increasing IGFBP-3 expression, and that IGFBP-3 is a significant tumor suppressor.

PPARγ induces growth inhibition and apoptosis through upregulation of insulin-like growth factor-binding protein-3 in gastric cancer cells.

Peroxisome proliferator activator receptor-gamma (PPARγ) is a ligand-activated transcriptional factor involved in the carcinogenesis of various cancers. Insulin-like growth factor-binding protein-3 (IGFBP-3) is a tumor suppressor gene that has anti-apoptotic activity. The purpose of this study was to investigate the anticancer mechanism of PPARγ with respect to IGFBP-3. PPARγ was overexpressed in SNU-668 gastric cancer cells using an adenovirus gene transfer system. The cells in which PPARγ was overexpressed exhibited growth inhibition, induction of apoptosis, and a significant increase in IGFBP-3 expression. We investigated the underlying molecular mechanisms of PPARγ in SNU-668 cells using an IGFBP-3 promoter/luciferase reporter system. Luciferase activity was increased up to 15-fold in PPARγ transfected cells, suggesting that PPARγ may directly interact with IGFBP-3 promoter to induce its expression. Deletion analysis of the IGFBP-3 promoter showed that luciferase activity was markedly reduced in cells without putative p53-binding sites (-Δ1755, -Δ1795). This suggests that the critical PPARγ-response region is located within the p53-binding region of the IGFBP-3 promoter. We further demonstrated an increase in PPARγ-induced luciferase activity even in cells treated with siRNA to silence p53 expression. Taken together, these data suggest that PPARγ exhibits its anticancer effect by increasing IGFBP-3 expression, and that IGFBP-3 is a significant tumor suppressor.