77 research outputs found
Inhibition of IGF-1 Signalling Enhances the Apoptotic Effect of AS602868, an IKK2 Inhibitor, in Multiple Myeloma Cell Lines
Multiple myeloma (MM) is a B cell neoplasm characterized by bone marrow infiltration with malignant plasma cells. IGF-1 signalling has been explored as a therapeutic target in this disease. We analyzed the effect of the IKK2 inhibitor AS602868, in combination with a monoclonal antibody targeting IGF-1 receptor (anti-IGF-1R) in human MM cell lines. We found that anti-IGF-1R potentiated the apoptotic effect of AS602868 in LP1 and RPMI8226 MM cell lines which express high levels of IGF-1R. Anti-IGF-1R enhanced the inhibitory effect of AS602868 on NF-κB pathway signalling and potentiated the disruption of mitochondrial membrane potential caused by AS602868. These results support the role of IGF-1 signalling in MM and suggest that inhibition of this pathway could sensitize MM cells to NF-κB inhibitors
Bypassing cellular EGF receptor dependence through epithelial-to-mesenchymal-like transitions
Over 90% of all cancers are carcinomas, malignancies derived from cells of epithelial origin. As carcinomas progress, these tumors may lose epithelial morphology and acquire mesenchymal characteristics which contribute to metastatic potential. An epithelial-to-mesenchymal transition (EMT) similar to the process critical for embryonic development is thought to be an important mechanism for promoting cancer invasion and metastasis. Epithelial-to-mesenchymal transitions have been induced in vitro by transient or unregulated activation of receptor tyrosine kinase signaling pathways, oncogene signaling and disruption of homotypic cell adhesion. These cellular models attempt to mimic the complexity of human carcinomas which respond to autocrine and paracrine signals from both the tumor and its microenvironment. Activation of the epidermal growth factor receptor (EGFR) has been implicated in the neoplastic transformation of solid tumors and overexpression of EGFR has been shown to correlate with poor survival. Notably, epithelial tumor cells have been shown to be significantly more sensitive to EGFR inhibitors than tumor cells which have undergone an EMT-like transition and acquired mesenchymal characteristics, including non-small cell lung (NSCLC), head and neck (HN), bladder, colorectal, pancreas and breast carcinomas. EGFR blockade has also been shown to inhibit cellular migration, suggesting a role for EGFR inhibitors in the control of metastasis. The interaction between EGFR and the multiple signaling nodes which regulate EMT suggest that the combination of an EGFR inhibitor and other molecular targeted agents may offer a novel approach to controlling metastasis
Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease
Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.
Effects of Anacetrapib in Patients with Atherosclerotic Vascular Disease
BACKGROUND:
Patients with atherosclerotic vascular disease remain at high risk for cardiovascular events despite effective statin-based treatment of low-density lipoprotein (LDL) cholesterol levels. The inhibition of cholesteryl ester transfer protein (CETP) by anacetrapib reduces LDL cholesterol levels and increases high-density lipoprotein (HDL) cholesterol levels. However, trials of other CETP inhibitors have shown neutral or adverse effects on cardiovascular outcomes.
METHODS:
We conducted a randomized, double-blind, placebo-controlled trial involving 30,449 adults with atherosclerotic vascular disease who were receiving intensive atorvastatin therapy and who had a mean LDL cholesterol level of 61 mg per deciliter (1.58 mmol per liter), a mean non-HDL cholesterol level of 92 mg per deciliter (2.38 mmol per liter), and a mean HDL cholesterol level of 40 mg per deciliter (1.03 mmol per liter). The patients were assigned to receive either 100 mg of anacetrapib once daily (15,225 patients) or matching placebo (15,224 patients). The primary outcome was the first major coronary event, a composite of coronary death, myocardial infarction, or coronary revascularization.
RESULTS:
During the median follow-up period of 4.1 years, the primary outcome occurred in significantly fewer patients in the anacetrapib group than in the placebo group (1640 of 15,225 patients [10.8%] vs. 1803 of 15,224 patients [11.8%]; rate ratio, 0.91; 95% confidence interval, 0.85 to 0.97; P=0.004). The relative difference in risk was similar across multiple prespecified subgroups. At the trial midpoint, the mean level of HDL cholesterol was higher by 43 mg per deciliter (1.12 mmol per liter) in the anacetrapib group than in the placebo group (a relative difference of 104%), and the mean level of non-HDL cholesterol was lower by 17 mg per deciliter (0.44 mmol per liter), a relative difference of -18%. There were no significant between-group differences in the risk of death, cancer, or other serious adverse events.
CONCLUSIONS:
Among patients with atherosclerotic vascular disease who were receiving intensive statin therapy, the use of anacetrapib resulted in a lower incidence of major coronary events than the use of placebo. (Funded by Merck and others; Current Controlled Trials number, ISRCTN48678192 ; ClinicalTrials.gov number, NCT01252953 ; and EudraCT number, 2010-023467-18 .)
Downregulation of the type 1 insulin-like growth factor receptor in mouse melanoma cells is associated with enhanced radiosensitivity and impaired activation of Atm kinase.
The type 1 insulin-like growth factor receptor (IGF1R) is required for growth, tumorigenicity and protection from apoptosis. IGF1R overexpression is associated with radioresistance in breast cancer. We used antisense (AS) RNA to downregulate IGF1R expression in mouse melanoma cells. Cells expressing AS-IGF1R transcripts were more radiosensitive in vitro and in vivo than controls. Also they showed reduced radiation-induced p53 accumulation and p53 serine 18 phosphorylation, and radioresistant DNA synthesis. These changes were reminiscent of the cellular phenotype of the human genetic disorder ataxia-telangiectasia (A-T), caused by mutations in the ATM gene. Cellular Atm protein levels were lower in AS-IGF1R-transfected cells than in control cells, although there was no difference in Atm expression at the transcriptional level. AS-IGF1R cells had detectable basal Atm kinase activity, but failed to induce kinase activity after irradiation. This suggests that IGF1R signalling can modulate the function of Atm, and supports the concept of targeted IGF1R downregulation as a potential treatment for malignant melanoma and other radioresistant tumours
Left ventricle unloading strategies in ECMO: A single‐center experience
ECMO is a life-saving technology capable of restoring perfusion but is not without significant complications that limit its realizable therapeutic benefit. ECMO-induced hemodynamics increase cardiac afterload risking left ventricular distention and impaired cardiac recovery. To mitigate potentially harmful effects, multiple strategies to unload the left ventricle (LV) are used in clinical practice but data supporting the optimal approach is presently lacking. We reviewed outcomes of our ECMO population from September 2015 through January 2019 to determine if our LV unloading strategies were associated with patient outcomes. We compared reactive (Group 1, n=30) versus immediate (Group 2, n=33) LV unloading and then compared patients unloaded with an Impella CP (n=19) versus an intra-aortic balloon pump (IABP, n=16), analyzing survival and ECMO-related complications. Survival was similar between Groups 1 and 2 (33 vs 42%, p=0.426) with Group 2 experiencing more clinically-significant hemorrhage (40 vs. 67%, p=0.034). Survival and ECMO-related complications were similar between patients unloaded with an Impella versus an IABP. However, the Impella group exhibited a higher rate of survival (37%) than predicted by their median SAVE score (18%). Our findings correlate with recent large cohort studies and motivate further work to design clinical guidelines and future trial design
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