Anticolon Cancer Effect of Korean Red Ginseng via Autophagy- and Apoptosis-Mediated Cell Death

Ginseng (Panax ginseng Meyer) has been used in East Asian traditional medicine for a long time. Korean red ginseng (KRG) is effective against several disorders, including cancer. The cytotoxic effects of KRG extract in terms of autophagy- and apoptosis-mediated cell death and its mechanisms were investigated using human colorectal cancer lines. KRG induced autophagy-mediated cell death with enhanced expression of Atg5, Beclin-1, and LC3, and formed characteristic vacuoles in HCT-116 and SNU-1033 cells. An autophagy inhibitor prevented cell death induced by KRG. KRG generated mitochondrial reactive oxygen species (ROS); antioxidant countered this effect and decreased autophagy. KRG caused apoptotic cell death by increasing apoptotic cells and sub-G₁ cells, and by activating caspases. A caspase inhibitor suppressed cell death induced by KRG. KRG increased phospho-Bcl-2 expression, but decreased Bcl-2 expression. Moreover, interaction of Bcl-2 with Beclin-1 was attenuated by KRG. Ginsenoside Rg2 was the most effective ginsenoside responsible for KRG-induced autophagy- and apoptosis-mediated cell death. KRG induced autophagy- and apoptosis-mediated cell death via mitochondrial ROS generation, and thus its administration may inhibit colon carcinogenesis.

Comparative Study of Autophagy in Oxaliplatin-Sensitive and Resistant SNU-C5 Colon Cancer Cells

Few studies have evaluated the role of autophagy in the development of oxaliplatin (OXT) resistance in colon cancer cells. In this study, we compared the role of autophagy between SNU-C5 colon cancer cells and OXT-resistant SNU-C5 (SNU-C5/OXTR) cells. At the same concentration of OXT, the cytotoxicity of OXT or apoptosis was significantly reduced in SNU-C5/OXTR cells compared with that in SNU-C5 cells. Compared with SNU-C5 cells, SNU-C5/OXTR cells exhibited low levels of autophagy. The expression level of important autophagy proteins, such as autophagy-related protein 5 (Atg5), beclin-1, Atg7, microtubule-associated proteins 1A/1B light chain 3B I (LC3-I), and LC3-II, was significantly lower in SNU-C5/OXTR cells than that in SNU-C5 cells. The expression level of the autophagy-essential protein p62 was also lower in SNU-C5/OXTR cells than in SNU-C5 cells. In SNU-C5/OXTR cells, the production of intracellular reactive oxygen species (ROS) was significantly higher than that in SNU-C5 cells, and treatment with the ROS scavenger N-acetylcysteine restored the reduced autophagy levels. Furthermore, the expression of antioxidant-related nuclear factor erythroid 2-related factor 2 transcription factor, heme oxygenase-1, and Cu/Zn superoxide dismutase were also significantly increased in SNU-C5/OXTR cells. These findings suggest that autophagy is significantly reduced in SNU-C5/OXTR cells compared with SNU-C5 cells, which may be related to the production of ROS in OXT-resistant cells.

Depression is a major determinant of both disease-specific and generic health-related quality of life in people with severe COPD

The quality of life of patients with chronic obstructive pulmonary disease (COPD) decreases significantly as the disease progresses; those with severe COPD are affected most. This article investigates predictors of the disease-specific and generic health-related quality of life (HRQL) in patients with severe COPD. This multicentre prospective cross-sectional study enrolled 80 patients with severe COPD. At enrolment, all patients completed a disease-specific instrument, the St George’s Respiratory Questionnaire (SGRQ), and a generic instrument, the Short Form 36 Health Survey Questionnaire (SF-36). The data were analyzed by Pearson’s correlation and multiple linear regression. The mean age of the patients was 66 ± 8 years; 93% were males. The SGRQ and SF-36 scores were not influenced by age or sex. Depression, dyspnea, the number of exacerbations, and exercise capacity significantly predicted the total SGRQ score (p < 0.05). Depression was the strongest determinant of the total SGRQ score. The SF-36 physical component summary scores were related to depression, dyspnea, and the number of exacerbations (p < 0.05). In comparison, the SF-36 mental component summary scores were related to depression and anxiety (p < 0.05). Depression is a significant determinant of both the disease-specific and generic HRQL in patients with severe COPD. Screening and early intervention for depression in patients with severe COPD could improve the HRQL.

Epac2a-null mice exhibit obesity-prone nature more susceptible to leptin resistance

BACKGROUND

The exchange protein directly activated by cAMP (Epac), which is primarily involved in cAMP signaling, has been known to be essential for controlling body energy metabolism. Epac has two isoforms: Epac1 and Epac2. The function of Epac1 on obesity was unveiled using Epac1 knockout (KO) mice. However, the role of Epac2 in obesity remains unclear.

METHODS

To evaluate the role of Epac2 in obesity, we used Epac2a KO mice, which is dominantly expressed in neurons and endocrine tissues. Physiological factors related to obesity were analyzed: body weight, fat mass, food intake, plasma leptin and adiponectin levels, energy expenditure, glucose tolerance, and insulin and leptin resistance. To determine the mechanism of Epac2a, mice received exogenous leptin and then hypothalamic leptin signaling was analyzed.

RESULTS

Epac2a KO mice appeared to have normal glucose tolerance and insulin sensitivity until 12 weeks of age, but an early onset increase of plasma leptin levels and decrease of plasma adiponectin levels compared with wild-type mice. Acute leptin injection revealed impaired hypothalamic leptin signaling in KO mice. Consistently, KO mice fed a high-fat diet (HFD) were significantly obese, presenting greater food intake and lower energy expenditure. HFD-fed KO mice were also characterized by greater impairment of hypothalamic leptin signaling and by weaker leptin-induced decrease in food consumption compared with HFD-fed wild-type mice. In wild-type mice, acute exogenous leptin injection or chronic HFD feeding tended to induce hypothalamic Epac2a expression.

CONCLUSIONS

Considering that HFD is an inducer of hypothalamic leptin resistance and that Epac2a functions in pancreatic beta cells during demands of greater work load, hypothalamic Epac2a may have a role in facilitating leptin signaling, at least in response to higher metabolic demands. Thus, our data indicate that Epac2a is critical for preventing obesity and thus Epac2a activators may be used to manage obesity and obesity-mediated metabolic disorders.

Assessment of Adrenal Function and Health-Related Quality of Life in Advanced Gastric Cancer Patients Who Received First-Line Chemotherapy

OBJECTIVE

We performed this prospective study to identify both the incidence of adrenal insufficiency (AI) and health-related quality of life (HRQOL) in advanced gastric cancer (AGC) patients who were treated with the S-1 plus cisplatin (SP) regimen as a first-line palliative chemotherapy.

METHODS

We assessed adverse events (AEs) observed in 52 patients who received the SP regimen for AGC between January 2009 and June 2010 using the Common Toxicity Criteria Adverse Events (CTCAE) version 3.0. Adrenal function was assessed at baseline and 12 weeks after chemotherapy using the low-dose adrenocorticotropic hormone stimulation test. HRQOL was assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire version 3.0 (EORTC-QLQ C30).

RESULTS

The incidence of AI was 30.8% (n = 16) and of AE observed 55% (n = 29) among 52 patients after 12 weeks of chemotherapy. Of 29 patients with AE, 34.4% (n = 10) were diagnosed with AI, and of 23 patients without AE, 26.1% (n = 6) were diagnosed with AI.

CONCLUSION

The incidence of secondary AI in AGC patients was not rare and was not correlated with the presence of nonspecific AEs. Although patients diagnosed with AI did not show any related symptoms, they are at risk of potentially life-threatening consequences. Thus, the evaluation of AI could be suggested for patients who received chemotherapy.

Delphinidin prevents high glucose-induced cell proliferation and collagen synthesis by inhibition of NOX-1 and mitochondrial superoxide in mesangial cells

This study examined the effect of delphinidin on high glucose-induced cell proliferation and collagen synthesis in mesangial cells. Glucose dose-dependently (5.6-25 mM) increased cell proliferation and collagen I and IV mRNA levels, whereas pretreatment with delphinidin (50 μM) prevented cell proliferation and the increased collagen mRNA levels induced by high glucose (25 mM). High glucose increased reactive oxygen species (ROS) generation, and this was suppressed by pretreating delphinidin or the antioxidant N-acetyl cysteine. NADPH oxidase (NOX) 1 was upregulated by high glucose, but pretreatment with delphinidin abrogated this upregulation. Increased mitochondrial superoxide by 25 mM glucose was also suppressed by delphinidin. The NOX inhibitor apocynin and mitochondria-targeted antioxidant Mito TEMPO inhibited ROS generation and cell proliferation induced by high glucose. Phosphorylation of extracellular signal regulated kinase (ERK)1/2 was increased by high glucose, which was suppressed by delphinidin, apocynin or Mito TEMPO. Furthermore, PD98059 (an ERK1/2 inhibitor) prevented the high glucose-induced cell proliferation and increased collagen mRNA levels. Transforming growth factor (TGF)-β protein levels were elevated by high glucose, and pretreatment with delphinidin or PD98059 prevented this augmentation. These results suggest that delphinidin prevents high glucose-induced cell proliferation and collagen synthesis by inhibition of NOX-1 and mitochondrial superoxide in mesangial cells.

Abstract P4-01-06: Microcalcifications as imaging biomarker in breast cancer: High-throughput radiogenomic analysis using microarrya data

Purpose: To investigate relationships between microcalcifications and gene expression pattern using microarray analysis in breast cancer.

Materials and methods: The institutional review board approved this retrospective study and waived the informed consent. Clinicopathologic finding, mammographic features, and gene expression data were evaluated in 133 women (mean age, 50.1 years; range, 21-79 years) with stage I-III breast cancer. Women with microcalcifications (n=33) and without microcalcifications (n=100) were compared. Immunohistochemical analysis of estrogen receptor, progesterone receptor, HER-2, and Ki-67 expression was performed. Differentially expressed genes (DEGs) using Affymetrix GeneChip® Human Gene 2.0 ST arrays (53,427 probes) were identified in tissue with microcalcifications versus without microcalcifications. In addition, genes included in the prediction analysis of PAM50, MammaPrint® and OncotypeDX® were also compared between two groups (microcalcifications versus no calcification). To further investigate the functions and underlying biology of DEGs, we performed enrichment analysis using the Gene Ontology database and pathway anlyais using the Kyoto Encyclopedia of Genes and Genomes database and Ingenuity Pathway Analysis.

Results: Among clinicopathologic varibales, HER2 positivity (p&lt;0.001) and presence of comedo necrosis (p=0.024) are significantly higher in the calcification group. About 128 genes had differential expression (&gt; 1.5 fold difference, adjusted p value&lt;0.05). Among known gene signatures, GRB7 (fold change=2.26, p=0.006) and ERBB2 (fold change=2.13, p=0.001) which are known as associated with recurrence, cell invasion and poor survival were highly expressed. In contrast, ZNF385B which is associated with p53-mediated apoptosis and good prognosis was underexpressed (fold change=0.39, p=0.001) in calcification group. Significant gene ontology terms included response to wounding, coagulation, wound healing, and response to hypoxia. Network and canonical pathway analysis indicated that increased cellular movement, cellular growth and proliferation, cellular develoment, coagulation and atherosclerosis signaling in breast cancer with microcalcifications, suggesting biological aggressiveness.

Conclusion: Gene expression patterns are different according to microcalcifications status in breast cancer. Breast cancers with mammographic microcalcifications are associated with metabolic aggressiveness and poor prognosis.

Citation Format: Shin SU, Kim W, Song SE, Chu A, Han W, Moon WK. Microcalcifications as imaging biomarker in breast cancer: High-throughput radiogenomic analysis using microarrya data. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P4-01-06.

Prevalence of Farm and Slaughterhouse Workers Carrying Shiga Toxin-Producing Escherichia coli in Korea

OBJECTIVES

The aim of this study was to investigate the distribution of Shiga toxin (Stx) gene-positive stool samples from dairy farmer and slaughterhouse workers in Gyeonggi-Do province.

METHODS

A total of 621 samples from healthy farmers and 198 samples from slaughterhouse workers were screened by polymerase chain reaction (PCR) for Shiga toxigenic Escherichia coli (STEC) infection on stool samples.

RESULTS

The PCR product of Stx-encoding genes was detected in 21 (3.4%) of 621 farmers and 15 (7.6%) of 198 slaughterhouse workers' stool samples. Distribution of the Stx PCR positive workers by age increment revealed an increase in STEC infection with age increment in both workers. Distribution of the Stx PCR positive workers by working years revealed an increase in STEC infection with working years in farmers.

CONCLUSION

These results of the study show that slaughterhouse workers are at higher risk of STEC infection than farmers. In addition, slaughterhouse workers have a more potential source of food contamination of STEC and transmission.

IGFBP5 mediates high glucose-induced cardiac fibroblast activation

This study examined whether IGF-binding protein 5 (IGFBP5) is involved in the high glucose-induced deteriorating effects in cardiac cells. Cardiac fibroblasts and cardiomyocytes were isolated from the hearts of 1- to 3-day-old Sprague Dawley rats. Treatment of fibroblasts with 25 mM glucose increased the number of cells and the mRNA levels of collagen III, matrix metalloproteinase 2 (MMP2), and MMP9. High glucose increased ERK1/2 activity, and the ERK1/2 inhibitor PD98059 suppressed high glucose-mediated fibroblast proliferation and increased collagen III mRNA levels. Whereas high glucose increased both mRNA and protein levels of IGFBP5 in fibroblasts, high glucose did not affect IGFBP5 protein levels in cardiomyocytes. The high glucose-induced increase in IGFBP5 protein levels was inhibited by PD98059 in fibroblasts. While recombinant IGFBP5 increased ERK phosphorylation, cell proliferation, and the mRNA levels of collagen III, MMP2, and MMP9 in fibroblasts, IGFBP5 increased c-Jun N-terminal kinase phosphorylation and induced apoptosis in cardiomyocytes. The knockdown of IGFBP5 inhibited high glucose-induced cell proliferation and collagen III mRNA levels in fibroblasts. Although high glucose increased IGF1 levels, IGF1 did not increase IGFBP5 levels in fibroblasts. The hearts of Otsuka Long-Evans Tokushima Fatty rats and the cardiac fibroblasts of streptozotocin-induced diabetic rats showed increased IGFBP5 expression. These results suggest that IGFBP5 mediates high glucose-induced profibrotic effects in cardiac fibroblasts.

Lack of inducible nitric oxide synthase prevents lipid-induced skeletal muscle insulin resistance without attenuating cytokine level

We examined whether deletion of inducible nitric oxide synthase (iNOS) could prevent lipid infusion-induced insulin resistance in iNOS-knockout and wild-type mice with the in vivo euglycemic-hyperinsulinemic clamp technique. Plasma NO metabolites were increased in lipid-infused wild-type mice, while they were not increased in iNOS-knockout mice. Plasma tumor necrosis factor-α levels were increased in both wild-type and iNOS-knockout by lipid-infusion. Lipid infusion reduced glucose infusion rate (GIR) and whole body glucose uptake in wild-type mice, whereas iNOS-knockout mice displayed comparable GIR and whole body glucose uptake compared with the control. In the gastrocnemius, lipid infusion decreased glucose uptake and glycolysis that were accompanied with increased phosphorylation of c-Jun N-terminal kinase and reduced phosphorylation of phosphoinositide 3-kinases and serine/threonine kinase Akt. However, lipid infusion did not affect glucose uptake or phosphorylation of these proteins in iNOS-knockout mice. The mRNA levels of inflammatory cytokines were also increased in the gastrocnemis of wild-type and iNOS-knockout mice by lipid infusion. Nitrotyrosine level in the gastrocnemius was increased in lipid-infused wild-type mice but it was not increased in iNOS-knockout mice. These results suggest that lack of iNOS prevents lipid infusion-induced skeletal muscle insulin resistance without attenuating cytokine levels.

Adiponectin inhibits palmitate-induced apoptosis through suppression of reactive oxygen species in endothelial cells: involvement of cAMP/protein kinase A and AMP-activated protein kinase

The present study examined whether adiponectin can inhibit palmitate-induced apoptosis, and also the associated mechanisms and signal transduction pathways in human umbilical vein endothelial cells. Cells treated with 500 μM palmitate for 48 h increased reactive oxygen species (ROS) generation and induced apoptosis. Treatment with antioxidant N-acetyl-L-cysteine (1 mM) and globular adiponectin (5 μg/ml) inhibited palmitate-induced ROS generation and apoptosis. The AMP-activated protein kinase (AMPK) activator 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR; 1 mM), and cAMP activators forskolin (10 μM) and cholera toxin (200 ng/ml) also displayed the same effects. The inhibitory effects of adiponectin on ROS generation and apoptosis were reversed by the AMPK inhibitor compound C (40 μM), cAMP inhibitor SQ22536 (50 μM), and protein kinase A (PKA) inhibitor H-89 (10 μM). The inhibitory effect of forskolin on palmitate-induced apoptosis was reversed by compound C, whereas the inhibitory effect of AICAR was not reversed by SQ22536 and H-89. AICAR and forskolin could not inhibit palmitate-induced apoptosis in cells treated with dominant-negative AMPK. Forskolin increased phosphorylated AMPK at both Thr-172 and Ser-485/491. These results suggest that adiponectin inhibits palmitate-induced apoptosis by suppression of ROS generation via both the cAMP/PKA and AMPK pathways. Interaction between cAMP/PKA and AMPK pathways may be involved.

Antepartum risk factors associated with peripartum cesarean hysterectomy in women with placenta previa

The objective of this study was to identify antepartum risk factors for peripartum hysterectomy in women with placenta previa. The medical records of women with placenta previa who underwent cesarean section (C/S) were reviewed retrospectively. Data regarding the reproductive history and peripartum outcomes were analyzed. Multivariable analysis was used to identify factors independently associated with hysterectomy. During an 8.5-year period, 346 cases of placenta previa were identified in 24,987 deliveries (1.4%). An emergent hysterectomy was performed in 31 patients (9.0%). Multiparity, total previa, history of abortion, C/S, and placenta previa was more common in the hysterectomy group. An increasing number of abortions and C/S were associated with a higher frequency of hysterectomy. By the multivariable analysis, previous abortion, previous C/S, and total previa were significant risk factors for hysterectomy. We concluded that in women with placenta previa, history of abortion as well as prior C/S, and a total previa are strong antepartum risk factors for peripartum hysterectomy.