Timosaponin AIII Suppresses Hepatocyte Growth Factor-Induced Invasive Activity through Sustained ERK Activation in Breast Cancer MDA-MB-231 Cells

Background. The aim of this study was to investigate the mechanisms by which Timosaponin AIII (TAIII) is able to inhibit HGF-induced invasion activity in the triple negative breast cancer cell line MDA-MB-231. Methods. After pretreatment with different concentrations (10−6~10−8 M) of TAIII, the cells were treated with hepatocyte growth factor (HGF, 15 ng/mL). At different time intervals after coincubation, various parameters, including the expression of c-Met, ERK, COX2, and MMP-9, which were assessed by Western blotting or by real-time PCR, were analyzed. In addition, invasive activity was also monitored. Results. HGF was found to induce c-MET activation and ERK activation, together with increased COX2 protein expression; these changes were followed by a subsequent increase in invasive activity. TAIII was found to suppress HGF-induced invasive activity and COX2 gene expression in a concentration-dependent manner (10−6~10−8 M) in parallel with increases in the phosphoforms of c-Met and ERK after TAIII treatment. The mechanisms by which TAIII suppresses HGF-induced invasive activity were demonstrated to include sustained cytoplasmic and nuclear ERK activation; these led to a suppression of nuclear ATF2 activation, which was followed by downregulation of COX2 and MMP-9 transcription. Conclusion. TAIII suppresses HGF-induced invasive activity in MDA-MB-231 cells via sustained ERK activation

Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).

Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)

Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

Colon Cancer Cells with High Invasive Potential Are Susceptible to Induction of Apoptosis by a Selective Cox-2 Inhibitor

Cyclooxygenase-2 (COX-2) expression has been shown to correlate with the invasiveness of colon cancer cells. To further investigate this positive correlation and its possible therapeutic implications, a selective COX-2 inhibitor, etodolac, was tested on three variants of HT-29 colon cancer cell lines, HT-29/Inv1, HT-29/Inv2 and HT-29/ Inv3, with graded increases of in vitro Matrigel invasive potential and COX-2 expression levels. HT-29 variants with higher invasive potential were found to be more sensitive to etodolac by in vitro growth inhibition assays, the estimated LD50 being 0.5 mM for highly invasive HT-29/Inv2 and HT-29/Inv3 cells, 0.6 mM for slightly less invasive HT- 29/Inv1, and 1.8 mM for the parental HT-29. Treatment of the highly invasive HT-29/Inv2 and Inv3 variants with as little as 0.1 mM etodolac in the growth medium produced signs of apoptosis , as detected by DNA fragmentation and TUNEL ( terminal deoxynucleotidyl transferase dUTP-biotin nick end labeling) assay. In vivo experiments in SCID mice showed that etolodac inhibited the growth of subcutaneous tumors induced by HT-29/Inv3 cells significantly more than those by the parental HT-29 cells. These results suggest that COX-2 inhibitors have a potential role in prevention of tumor invasion in colon cancer patients

Secretory RAB GTPase 3C modulates IL6-STAT3 pathway to promote colon cancer metastasis and is associated with poor prognosis

Abstract Background RAB GTPases are important in the regulation of membrane trafficking and cell movement. Recently, exocytic RABs have received increasing attention in cancer research. However, the functional roles of exocytic RABs in colorectal carcinogenesis remain to be elucidated. Methods Immunohistochemistry analysis of a microarray containing 215 colorectal adenocarcinoma tissues was used to identify the association between exocytic RABs and patient prognosis. Complementary functional RAB3C overexpression and knockdown experiments were performed. The molecular mechanism of RAB3C in inducing colon cancer cell metastasis was determined. Results High RAB3C expression in patients was found to be significantly associated with advanced pathological stage, distant metastasis and poor prognosis. Multivariate analyses showed that high RAB3C expression was an independent prognostic marker in overall (P = 0.001) and disease-free survival (P < 0.001). Furthermore, our experimental results showed an increase in the migration and invasion ability of RAB3C-overexpressing colon cancer cells and increased metastatic nodules in a mouse metastasis model. The effect of RAB3C-overexpressing cell-conditioned medium was found to significantly promote the migration ability of parental colon cancer cells, thus suggesting that the promotion of migration is exocytosis dependent. Upregulation of other exocytic RABs was also seen in RAB3C-overexpressing cells. Through microarray and proteomics analyses, increased production of multiple cytokines was observed in RAB3C-overexpressing cell lines, and the IL-6 pathway was the top pathway whose members exhibited gene expression changes after RAB3C overexpression, according to Ingenuity Pathway Analysis. Blocking IL-6 with IL-6 antibody treatment or IL-6 knockdown significantly inhibited the migration potential of RAB3C-overexpressing colon cancer cells. In addition, IL-6 was found to induce STAT3 phosphorylation in RAB3C-overexpressing colon cancer cells, thus promoting migration. Ruxolitinib, a JAK2 inhibitor, was found to significantly inhibit RAB3C-induced colon cancer cell migration. Conclusions Our study revealed that RAB3C overexpression promotes tumor metastasis and is associated with poor prognosis in colorectal cancer, through modulating the ability of cancer cells to release IL-6 through exocytosis and activate the JAK2-STAT3 signaling pathway. These results further suggest that inhibition of STAT3 phosphorylation in the RAB3C-IL-6-STAT3 axis by using Ruxolitinib may be a new therapeutic strategy to combat metastatic colon cancers