Amentoflavone induces caspase-dependent/-independent apoptosis and dysregulates cyclin-dependent kinase-mediated cell cycle in colorectal cancer in vitro and in vivo.

Colorectal cancer (CRC) is recognized as the third most common malignancy and the second most deadly in highly developed countries. Although the treatment of CRC has improved in the past decade, the mortality rate of CRC is still increasing. Amentoflavone, one of the flavonoids detected in medical plants, is reported to possess potential anticancer properties in various cancers. However, its role in CRC has not been studied. This study aimed to investigate the role and underlying mechanism of amentoflavone on CRC in vitro and in vivo. We identified the cytotoxicity, apoptosis effect, cell cycle alteration, DNA damage induction and tumor progression inhibition of amentoflavone in HT-29 model by using MTT assay, flow cytometry, immunofluorescence (IF) staining, Western blotting and animal experiments. Amentoflavone induced cytotoxicity is caused by triggering G1 arrest, DNA damage and apoptosis in HT-29 cells. The expression of cyclin D1, CDK4 and CDK6 was decreased by amentoflavone; in contrast, the phosphorylation of ATM and CHK2 and the expression of p21 and p27 were increased. The apoptosis induction of amentoflavone in CRC is not only caspase-dependent but also increases EndoG and AIF nuclear translocation in a caspase-independent manner. Importantly, the apoptosis induction of amentoflavone is not affected by the activity of p53 in CRC. Amentoflavone suppressed the progression of CRC by initiating G1 arrest and ATM/CHK2-mediated DNA damage-responsive, caspase-dependent/independent apoptotic effects. We uncovered a novel tumor-inhibitory role of amentoflavone in CRC that is not associated with p53 activity, which may serve as a potential treatment for CRC.

The relationship between pulse pressure with plasma PCSK9 and interleukin-6 among patients with acute ischemic stroke and dyslipidemia.

BACKGROUND AND PURPOSE: A high plasma concentration of proprotein convertase subtilisin/kexin type 9 is characteristic of a prothrombotic state in cardiovascular diseases. Elevated inflammatory markers, such as interleukin-6, are associated with worse outcomes after ischemic stroke. We aimed to study the role of plasma PCSK9 and IL-6 in acute ischemic stroke with dyslipidemia. METHODS: We divided 123 enrolled patients with first-ever acute ischemic stroke into normotensive and high blood pressure groups and further into high and low pulse pressure subgroups. Clinical characteristics and inflammatory and metabolic parameters, including plasma PCSK9 and IL-6, were recorded. RESULTS: After the analysis of the normotensive and BP groups, there were positive correlations between PP and carotid stenosis (P = 0.031) and plaque numbers (P = 0.013) and between National Institute of Health Stroke Scale scores (P = 0.019) and carotid stenosis severity (P = 0.021) and resistance index (P = 0.04). There was a significant association between plasma cholesterol and PCSK9 (P = 0.044) in the low PP subgroup and IL-6 (P = 0.042) in the high PP subgroup. CONCLUSIONS: Our findings indicated that plasma PCSK9 levels were associated with the low PP subgroup, while IL-6 was associated with the high PP subgroup. Dyslipidemia control is also necessary for those who had a stroke and who have high PP. Further investigation to assess the role of PCSK9 and IL-6 in patients with stroke is required for early treatment and secondary prevention.

Spine trabecular bone scores and bone mineral density of postmenopausal Taiwanese women.

OBJECTIVES: The aims of the study were to determine the mean trabecular bone score (TBS) of postmenopausal Taiwanese women and to analyze the value of TBS in predicting osteoporosis. METHODS: A total of 1,915 postmenopausal women with lumbar spine and hip bone mineral density (BMD) and spine TBS were enrolled from a single medical center into this study. The women's BMD and TBS were measured using dual x-ray absorptiometry (Discovery Wi; Hologic, Bedford, Mass) and iNsight software (Med-Imaps SASU, Merignac, France), respectively. The women's demographic characteristics; lumbar spine, total hip, and femoral neck BMD; and lumbar spine TBS were recorded, and correlations among the parameters were identified using a 2-tailed Pearson test, in which a P value less than 0.05 was considered statistically significant. We developed simple linear regression models to represent changes related to TBS and performed an analysis of variance on the selected variables. RESULTS: The average age of the women was 62.5 ± 9.1 years (range, 25.7-93.7 years). The mean TBS was 1.300 ± 0.086 (range, 1.015-1.596). The TBS was weakly and negatively correlated with body mass index ( r = -0.078) and moderately and positively correlated with the lumbar spine BMD ( r = 0.619). The patients' lowest BMD values among those measured at multiple sites revealed a higher rate of osteoporosis (32.5%) than those measured at individual sites. Degraded TBS were noted in 21.2% of the participants, and a combination of BMD and TBS results predicted more individuals (7.8%) at a high risk of fracture than did the BMD result only. The rates of both osteoporosis and degraded TBS increased with age. CONCLUSIONS: Bone mineral density and TBS can be used in combination to predict osteoporosis in a greater number of postmenopausal Taiwanese women. Because the incidence of osteoporosis is the highest among older women, clinicians should pay careful attention to TBS degradation among older patients without low BMD.

The inhibitory effect and mechanism of quetiapine on tumor progression in hepatocellular carcinoma in vivo.

Hepatocellular carcinoma (HCC) is the primary tumor of the liver and the fourth leading cause of cancer-related death. Recently, several studies indicated the anti-tumor potential of antipsychotic medicine. Quetiapine, an atypical antipsychotic, is used to treat schizophrenia, bipolar disorder, and major depressive disorder since 1997. However, whether quetiapine may show potential to suppress HCC progression and its underlying mechanism is persisting unclear. Quetiapine has been shown to induce apoptosis and inhibit invasion ability in HCC in vitro. Here, we established two different HCC (Hep3B, SK-Hep1) bearing animals to identify the treatment efficacy of quetiapine. Tumor growth, signaling transduction, and normal tissue pathology after quetiapine treatment were validated by caliper, bioluminescence image, immunohistochemistry (IHC), and hematoxylin and eosin staining, respectively. Quetiapine suppressed HCC progression in a dose-dependent manner. Extracellular signal-regulated kinases (ERKs) and Nuclear factor-κB (NF-κB) mediated downstream proteins, such as myeloid leukemia cell differentiation protein (MCL-1), cellular FLICE-inhibitory protein (C-FLIP), X-linked inhibitor of apoptosis protein (XIAP), Cyclin-D1, matrix metallopeptidase 9 (MMP-9), vascular endothelial growth factor-A (VEGF-A) and indoleamine 2,3-dioxygenase (IDO) which involved in proliferation, survival, angiogenesis, invasion and anti-tumor immunity were all decreased by quetiapine. In addition, extrinsic/intrinsic caspase-dependent and caspase-independent pathways, including cleaved caspase-3, -8, and - 9 were increased by quetiapine. In sum, the tumor inhibition that results from quetiapine may associate with ERK and NF-κB inactivation.

Lenvatinib Induces AKT/NF-κB Inactivation, Apoptosis Signal Transduction and Growth Inhibition of Non-small Cell Lung Cancer In Vivo.

BACKGROUND/AIM: Non-small cell lung cancer (NSCLC) is the most common type of lung cancer with poor prognosis. Lenvatinib is a multi-kinase inhibitor that has the potential to suppress tumor progression. Our previous study suggested that lenvatinib induces cytotoxicity and apoptosis in CL-1-5-F4 cells in vitro. However, whether lenvatinib suppresses NSCLC progression in vivo remains unclear. MATERIALS AND METHODS: Tumor growth inhibition and normal tissue toxicity evaluation following lenvatinib treatment were performed on CL-1-5-F4-bearing mice. RESULTS: Tumor growth calculated by caliper and living cell intensity decreased by lenvatinib treatment as analysed by bioluminescence imaging. Phosphorylation of AKT, NF-κB, and NF-κB downstream proteins involved in tumor progression were reduced by lenvatinib in the tumor tissue. No pathological changes were found in the liver, kidney, and spleen after lenvatinib treatment. CONCLUSION: Induction of apoptosis and suppression of AKT/NF-κB were associated with lenvatinib-induced inhibition of the progression of NSCLC in vivo.

Lenvatinib Inhibits AKT/NF-κB Signaling and Induces Apoptosis Through Extrinsic/Intrinsic Pathways in Non-small Cell Lung Cancer.

BACKGROUND/AIM: Non-small cell lung cancer (NSCLC) is a serious disease and the leading cause of death globally. Overexpression of protein kinase B/nuclear factor-kappa B (NF-κB) signaling transduction of NSCLC cells was recognized as a potential therapeutic target. Lenvatinib is a multiple kinase inhibitor against vascular endothelial growth factor receptor family. However, whether lenvatinib may affect AKT/NF-κB in NSCLC remains unknown. MATERIALS AND METHODS: MTT assay, NF-κB reporter gene assay, flow cytometry, tranwell migration/invasion analysis and western blotting were used to identify the alteration of cell viability, NF-κB activation, apoptosis effect, migration/invasion potential and AKT/NF-κB related protein expression, respectively, in CL-1-5-F4 cells after lenvatinib treatment. RESULTS: The cell viability and NF-κB activity were suppressed by lenvatinib. Extrinsic and intrinsic apoptosis were activated by lenvatinib. Additionally, the metastatic potential of CL-1-5-F4 cells was also suppressed by lenvatinib. CONCLUSION: Altogether, lenvatinib induced extrinsic/intrinsic apoptosis and suppressed migration/invasion ability of NSCLC cells that was associated with AKT/NF-κB signaling inactivation.

Therapeutic Efficacy and Inhibitory Mechanism of Regorafenib Combined With Radiation in Colorectal Cancer.

BACKGROUND: Although both chemotherapy and radiotherapy (RT) can sufficiently maintain tumor suppression of colorectal cancer (CRC), these treatments may trigger the expression of nuclear factor kappa B (NF-κB) and compromise patients' survival. Regorafenib suppresses NF-κB activity in various tumor types. However, whether regorafenib may act as a suitable radiosensitizer to enhance therapeutic efficacy of RT remains unknown. MATERIALS AND METHODS: Here, we established a CRC-bearing animal model to investigate the therapeutic efficacy of regorafenib in combination with RT, through measurement of tumor growth, body weight, whole-body computed tomography (CT) scan and immunohisto-chemistry staining. RESULTS: Smallest tumor size and weight were found in the combination treatment group. In addition, RT-induced up-regulation of NF-κB and downstream proteins were diminished by regorafenib. Moreover, the body weight and liver pathology in the treated group were similar to those of the non-treated control group. CONCLUSION: Regorafenib may enhance the anti-CRC efficacy of RT.

ERK/AKT Inactivation and Apoptosis Induction Associate With Quetiapine-inhibited Cell Survival and Invasion in Hepatocellular Carcinoma Cells.

BACKGROUND/AIM: Quetiapine, an atypical antipsychotic, has been encountered as a potential protective agent to suppress various types of tumor growth. However, the inhibitory mechanism of quetiapine in hepatocellular carcinoma (HCC) still remains unclear. The purpose of present study was to investigate the inhibitory mechanism of quetiapine on cell survival and invasion in HCC. MATERIALS AND METHODS: Changes of apoptotic signaling, migration/invasion ability, and signaling transduction involved in cell survival and invasion were evaluated with flow cytometry, migration/invasion, and western blot assays. RESULTS: Quetiapine inhibited cell proliferation and migration/invasion in SK-Hep1 and Hep3B cells. Quetiapine induced extrinsic and intrinsic apoptotic pathways. Activation of extracellular signal-regulated kinases (ERK), protein kinase B (AKT), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-ĸB), expression of anti-apoptotic, and metastasis-associated proteins were decreased by quetiapine. CONCLUSION: The apoptosis induction, the decreased expression of ERK/AKT-mediated anti-apoptotic and the metastasis-associated proteins were associated with quetiapine-inhibited cell survival and invasion in HCC in vitro.

Association of cyclophilin A level and pulse pressure in predicting recurrence of cerebral infarction.

Cyclophilin A (CypA), secreted from vascular smooth muscle cells and inflammatory cells in response to oxidative stress, promotes vascular atherosclerosis and development of carotid stenosis. Increased concentration of plasma CypA in acute cerebral infarction was demonstrated clinically. The primary aim of this study was to investigate the prognostic impact between CypA level and outcome in patients with acute ischemic stroke. Admission serum CypA concentrations were detected in 66 acute cerebral infarction patients and in 52 healthy individuals. Inflammatory biomarkers, including high-sensitivity C-reactive protein, adhesion molecules, interleukins, and matrix-metalloproteases, were also assessed. We also examined the relationship between plasma biomarkers, blood pressure (BP), pulse pressure, the carotid artery velocity, the prognostic assessment with modified Rankin scale, and stroke recurrence. Plasma CypA concentration was higher on the first day of hospitalization in the high BP stroke group than in normal BP stroke group, which was statistically significant, which was observed even in the third month and sixth month follow-up outpatient periods. For stroke recurrence prediction, there was an important association between the higher (>60) pulse pressure on the seventh day of hospitalization and CypA level on the third month and sixth month follow-up outpatient periods. Our study revealed higher circulating serum levels of CypA in the hypertensive stroke group than in the non-hypertensive stroke group. We expect that elevated plasma CypA level and raised pulse pressure during hospitalization to become valuable biomarkers in predicting stroke recurrence in the sixth month assessment of acute cerebral infarction.

Suppression of ERK/NF-κB Activation Is Associated With Amentoflavone-Inhibited Osteosarcoma Progression In Vivo.

BACKGROUND/AIM: Amentoflavone has been implicated in reducing the metastatic potential of osteosarcoma (OS) cells in vitro. The aim of the present study was to verify the antitumoral efficacy and the potential mechanism of amentoflavone osteosarcoma progression inhibition in vivo. MATERIALS AND METHODS: A U-2 OS osteosarcoma xenograft mouse model was used in this study. Mice were treated with a vehicle control or amentoflavone (100 mg/kg/day) for 15 days. Tumor growth, signal transduction, and expression of tumor progression-associated proteins were evaluated using a digital caliper, bioluminescence imaging (BLI), animal computed tomography (CT), and ex vivo western blotting assay. RESULTS: Amentoflavone significantly inhibits tumor growth and reduces protein levels of phospho-extracellular signal-regulated kinase (P-ERK), nuclear factor-kappaB (NF-κB) p65 (Ser536), vascular endothelial growth factor (VEGF), matrix metallopeptidase 9 (MMP-9), X-linked inhibitor of apoptosis protein (XIAP), and cyclin-D1 in osteosarcoma in vivo. CONCLUSION: The inhibition of ERK/NF-κB activation is associated with amentoflavone-inhibited osteosarcoma progression in vivo.

Fluoxetine Induces Apoptosis through Extrinsic/Intrinsic Pathways and Inhibits ERK/NF-κB-Modulated Anti-Apoptotic and Invasive Potential in Hepatocellular Carcinoma Cells In Vitro.

The aim of the present study was to verify the effects of fluoxetine on dysregulation of apoptosis and invasive potential in human hepatocellular carcinoma (HCC) SK-Hep1 and Hep3B cells. Cells were treated with different concentrations of fluoxetine for different times. MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assays were used for testing the effects of fluoxetine on cell viability. The regulation of apoptosis signaling, and anti-apoptotic, proliferation, and metastasis-associated proteins after fluoxetine treatment were assayed by flow cytometry and Western blotting assay. The detection of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) activation after fluoxetine treatment was performed by NF-κB reporter gene assay. The results demonstrated that fluoxetine significantly reduced cell viability, cell migration/invasion, NF-κB, extracellular signal-regulated kinases (ERK) activation, and expression of anti-apoptotic (Cellular FLICE (FADD-like IL-1ß-converting enzyme)-inhibitory protein (C-FLIP), Myeloid cell leukemia-1 (MCL-1), X-Linked inhibitor of apoptosis protein (XAIP), and Survivin), proliferation (Cyclin-D1), angiogenesis (vascular endothelial growth factor (VEGF)), and metastasis-associated proteins (matrix metalloproteinase-9 (MMP-9)). Fluoxetine also significantly induced apoptosis, unregulated extrinsic (activation of first apoptosis signal protein and ligand (Fas/FasL), and caspase-8) and intrinsic (loss of mitochondrial membrane potential (ΔΨm) pathways and increased Bcl-2 homologous antagonist killer (BAK) apoptosis signaling. Taken together, these results demonstrated that fluoxetine induced apoptosis through extrinsic/intrinsic pathways and diminished ERK/NF-κB-modulated anti-apoptotic and invasive potential in HCC cells in vitro.

Fluoxetine Inhibits DNA Repair and NF-ĸB-modulated Metastatic Potential in Non-small Cell Lung Cancer.

BACKGROUND/AIM: The aim of present study was to verify the effect of fluoxetine on DNA repair and metastatic potential in non-small cell lung cancer (NSCLC) in vitro. MATERIALS AND METHODS: Highly metastatic NSCLC CL1-5-F4 cells were used in this study. Cells were treated with different concentrations of fluoxetine or QNZ (NF-ĸB inhibitor) for 48 h. After treatment, cell viability, apoptotic signaling, NF-ĸB activation, expression of DNA repair and metastasis-associated proteins, and cell migration/invasion were evaluated by (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium assay, flow cytometry, NF-ĸB reporter gene, western blotting, and cell migration/invasion assay, respectively. RESULTS: Fluoxetine induced apoptosis and reduced cell viability, NF-ĸB activation, expression of DNA repair and metastasis-associated proteins, and cell migration/invasion in CL1-5-F4 cells. Also, NF-ĸB activation was the critical factor in fluoxetine-inhibited metastatic potential. CONCLUSION: Fluoxetine induced apoptosis and inhibited DNA repair and metastatic potential in NSCLC CL1-5-F4 cells.

Amentoflavone Inhibits Hepatocellular Carcinoma Progression Through Blockage of ERK/NF-ĸB Activation.

AIM: The aim of the present study was to confirm therapeutic efficacy and find probable mechanism of action of amentoflavone in hepatocellular carcinoma (HCC) in vivo. MATERIALS AND METHODS: Luciferase reporter vector pGL4.50_transfected SK-Hep1 (SK-Hep1/luc2) tumor-bearing mice were treated with vehicle or amentoflavone (100 mg/kg/day by gavage) for 14 days. Tumor growth, amentoflavone toxicity, and extracellular signal-regulated kinase (ERK)/nuclear factor-kappaB (NF-ĸB) signaling in tumor progression were evaluated with digital caliper, bioluminescence imaging, computed tomography, body weight, pathological examination of liver, and immunohistochemistry staining. RESULTS: Amentoflavone significantly inhibited tumor growth, ERK/NF-ĸB activation, and expression of tumor progression-associated proteins as compared to vehicle-treated group. In addition, body weight and liver morphology of mice were not influenced by amentoflavone treatment. CONCLUSION: These results suggest that amentoflavone inhibits HCC progression through suppression of ERK/NF-ĸB signaling.

Cyclophilin A: A Predictive Biomarker of Carotid Stenosis in Cerebral Ischemic Stroke.

BACKGROUND: Cyclophilin A plays a pathogenic role in the development and progression of atherosclerosis, which can be assessed by measuring carotid intima-media thickness. The primary aim of this study was to examine the interaction between plasma Cyclophilin A level and carotid intima-media thickness in patients with acute ischemic stroke. METHOD: Plasma concentration of Cyclophilin A was measured on admission in 66 consecutive patients who had been hospitalized for acute cerebral stroke and in 52 case-control subjects without a history of acute stroke. Subjects in both groups also underwent ultrasound B-mode imaging to measure the mean and maximum intima-media thickness of the carotid artery. Inflammatory biomarkers including high-sensitivity C-reactive protein and fibrinogen were also assessed. RESULTS: We found that the plasma concentration of Cyclophilin A was significantly higher in patients with acute ischemic stroke (p = 0.042). Increased Cyclophilin A was also correlated with carotid intima-media thickness in the patient group (p < 0.001). Among the risk factors for cerebral stroke examined in this study, only hypertension was significantly associated with plasma Cyclophilin A level. CONCLUSION: Increased plasma Cyclophilin A levels might be involved in the pathophysiology of acute ischemic stroke and Cyclophilin A might serve as a biomarker in risk assessment of acute stroke patients.

Amentoflavone Inhibits ERK-modulated Tumor Progression in Hepatocellular Carcinoma In Vitro.

BACKGROUND/AIM: A previous study indicated that amentoflavone inhibits tumor growth of breast cancer. However, the anti-cancer effects and mechanism of amentoflavone in hepatocellular carcinoma (HCC) have not been elucidated. The aim of the present study was to verify the effect of amentoflavone on tumor progression in HCC. MATERIALS AND METHODS: HCC SK-Hep1 cells were treated with different concentrations of amentoflavone or 10 µM PD98059 (extracellular signal-regulated kinases (ERK) inhibitor) for 48 h, respectively, and then cell viability, NF-κB activation, levels of tumor progression-associated proteins, and cell invasion were evaluated with 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), NF-κB reporter gene assay, western blotting, and cell invasion assay. RESULTS: The results demonstrated that both amentoflavone and PD98059 not only significantly reduced cell viability, NF-κB activation, and cell invasion, but also inhibited the expression of tumor progression-associated proteins. In addition, we found that amentoflavone suppresses ERK phosphorylation. CONCLUSION: The results of the present study suggest that amentoflavone down-regulates ERK-modulated tumor progression in HCC.

Hyperforin Suppresses Tumor Growth and NF-κB-mediated Anti-apoptotic and Invasive Potential of Non-small Cell Lung Cancer.

BACKGROUND/AIM: Previous studies have indicated that hyperforin inhibits tumor growth of hepatocellular carcinoma. However, the anticancer effects of hyperforin in non-small cell lung cancer (NSCLC) are ambiguous. The aim of the present study was to investigate the anticancer effect of hyperforin in NSCLC. NSCLC CL1-5-F4 cells were treated with different concentrations of hyperforin or NF-κB inhibitor (QNZ) for different time periods. MATERIALS AND METHODS: Change of cell viability, NF-κB activation, apoptotic signaling pathways, expression of anti-apoptotic proteins, and cell invasion were detected using the 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, NF-κB reporter gene assay, flow cytometry, western blotting, and cell invasion assay. RESULTS: The results demonstrated that hyperforin significantly promotes extrinsic and intrinsic apoptotic pathways, and inhibits cell viability and NF-κB activation. In addition, results also indicated that blockage of NF-κB activation reduces the levels of anti-apoptotic proteins and cell invasion in CL1-5-F4 cells. CONCLUSION: These results suggested hyperforin induces apoptosis and inhibits NF-κB-modulated anti-apoptotic and invasive potential in NSCLC.

Amentoflavone Induces Apoptosis and Inhibits NF-ĸB-modulated Anti-apoptotic Signaling in Glioblastoma Cells.

The goal of the present study was to investigate anticancer effect of amentoflavone on glioblastoma cells in vitro. Our results demonstrated that amentoflavone not only significantly reduced cell viability, nuclear factor-ĸappa B (NF-ĸB) activation, and protein expression of cellular Fas-associated protein with death domain-like interleukin 1 beta-converting enzyme inhibitory protein (C-FLIP) and myeloid cell leukemia 1 (MCL1), but significantly triggered cell accumulation at the sub-G1 phase, loss of mitochondrial membrane potential, and expression of active caspase-3 and -8. In order to verify the effect of NF-ĸB inhibitor on expression of anti-apoptotic proteins, we performed western blotting. We found that the of NF-ĸB inhibitor or amentoflavone markedly diminished protein levels of MCL1 and C-FLIP. Taken all together, our findings show that amentoflavone induces intrinsic and extrinsic apoptosis and inhibits NF-ĸB-modulated anti-apoptotic signaling in U-87 MG cells in vitro.

Protective Effects of Pyridoxamine Against UVC-induced Programmed Cell Death in HaCaT Cells.

BACKGROUND: Exposure to ultraviolet (UV) light is closely related to human diseases, such as skin cancer, due to irreversible injuries to the skin cells. The UV-induced DNA damage and programmed cell death are important determinants for skin carcinogenesis. The aim of the present study was to investigate the anti-ultraviolet-C (UVC) effects of pyridoxamine in human keratinocyte HaCaT cells and its mechanisms of action. RESULTS: UVC-induced programmed cell death in HaCaT cells was abrogated by treated the cells immediately after UVC irradiation with 40, 80 and 160 µM of pyridoxamine. Monitoring the UVC-induced-specific reactive oxygen species, we found that 20, 40, 80 and 160 µM of pyridoxamine was also effective in suppressing the induction of reactive oxygen species by UVC. CONCLUSION: Overall, our results provided evidence showing that pyridoxamine was effective in protecting HaCaT cells from UVC-induced programmed cell death and may be a potential anti-UVC agent in life and clinical practice.

Association of X-ray repair cross-complementing-6 genotypes with childhood leukemia.

BACKGROUND: The Non-homologous end-joining repair gene XRCC6/Ku70 plays an important role in the repair of DNA double-strand breaks (DSBs), and has been found to be involved in the carcinogenesis of many types of cancers including oral, prostate, breast and bladder cancer. However, the contribution of XRCC6 to childhood leukemia has yet to be studied. In the present study, we investigated the association of XRCC6 genotypes with the risk of childhood leukemia. MATERIALS AND METHODS: Two hundred and sixty-six patients with childhood leukemia and an equal number of age-matched healthy controls recruited in Central Taiwan, were genotyped investigating these polymorphisms' association with childhood leukemia. RESULTS: As for XRCC6 promoter T-991C, patients carrying the TC genotype had a significantly increased risk of childhood leukemia compared with the TT wild-type genotype [odds ratio (OR)=2.30, 95% confidence interval (CI)=1.38-3.84, p=0.0047]. Meanwhile, the genotypes of XRCC6 promoter C-57G, A-31G and intron3 were not statistically associated with childhood leukemia risk. CONCLUSION: Our findings suggest that the XRCC6 genotype could serve as a predictor of childhood leukemia risk and XRCC6 could serve as a target for personalized medicine and therapy.