Citations

Key points Loss of function of the melanocortin 4 receptor (MC4R) results in hyperphagia, obesity and increased growth. Despite knowing that MC4Rs control food intake, we are yet to understand why defects in the function of the MC4R receptor contribute to rapid linear growth. We show that hyperphagia following germline loss of MC4R in male mice promotes growth while suppressing the growth hormone–insulin‐like growth factor‐1 (GH–IGF‐1) axis. We propose that hyperinsulinaemia promotes growth while suppressing the GH–IGF‐1 axis. It is argued that physiological responses essential to maintain energy flux override conventional mechanisms of pubertal growth to promote the storage of excess energy while ensuring growth. AbstractDefects in melanocortin‐4‐receptor (MC4R) signalling result in hyperphagia, obesity and increased growth. Clinical observations suggest that loss of MC4R function may enhance growth hormone (GH)‐mediated growth, although this remains untested. Using male mice with germline loss of the MC4R, we assessed pulsatile GH release and insulin‐like growth factor‐1 (IGF‐1) production and/or release relative to pubertal growth. We demonstrate early‐onset suppression of GH release in rapidly growing MC4R deficient (MC4RKO) mice, confirming that increased linear growth in MC4RKO mice does not occur in response to enhanced activation of the GH–IGF‐1 axis. The progressive suppression of GH release in MC4RKO mice occurred alongside increased adiposity and the progressive worsening of hyperphagia‐associated hyperinsulinaemia. We next prevented hyperphagia in MC4RKO mice through restricting calorie intake in these mice to match that of wild‐type (WT) littermates. Pair feeding of MC4RKO mice did not prevent increased adiposity, but attenuated hyperinsulinaemia, recovered GH release, and normalized linear growth rate to that seen in pair‐fed WT littermate controls. We conclude that the suppression of GH release in MC4RKO mice occurs independently of increased adipose mass, and is a consequence of hyperphagia‐associated hyperinsulinaemia. It is proposed that physiological responses essential to maintain energy flux (hyperinsulinaemia and the suppression of GH release) override conventional mechanisms of pubertal growth to promote the storage of excess energy while ensuring growth. Implications of these findings are likely to extend beyond individuals with defects in MC4R signalling, encompassing physiological changes central to mechanisms of growth and energy homeostasis universal to hyperphagia‐associated childhood‐onset obesity.

Abstract Despite the rapid progress in personalized cancer therapy (PCT) for breast cancer, no previous studies have used genomic predictors to choose among multiple chemotherapy regimens. It is unclear that given the current regimens how much PCT can improve the response rate for patients who will receive chemotherapy. In this study, we reanalyzed data from published studies of 1111 breast cancer patients who were treated with neoadjuvant chemotherapies. Those patients were divided into three regimen groups: an anthracycline alone, anthracycline plus paclitaxel, and anthracycline plus docetaxel. We developed a new strategy called PRES (Personalized REgimen Selection) to reassign the optimal regimen to each of the patients. First, a variable selection scheme was developed to identify significant genetic predictors for chemotherapy response. The selected genetic variables were then combined with clinical variables to build random forest models to predict the response of a patient to each regimen using pCR (pathological complete response) as the measure of response. The models were used to assign an optimal regimen to each patient to maximize the chance of pCR. We found that the expected rate of pCR was improved from 21.2% to 39.6% (95% CI: 34.6% - 43.0%). We also found that 31.1% of the patients may have been overtreated and 8.2% patients undertreated. A validation study on 21 cell lines showed that our prediction agrees with their paclitaxel-sensitivity profiles. We performed additional analysis on the Cancer Genome Atlas (TCGA) data and found that 18 of the 19 genes identified are significantly differentially expressed between normal and tumor tissues, and 2 of them, TAF6L and METRN (meteorin), are associated with overall survival. In conclusion, PRES could substantially increase response rates for breast cancer patients who will receive one of the widely-accepted chemotherapy regimens at present. Citation Format: Jinfeng Zhang, Kaixian Yu, Qingxiang Amy Sang, Winston Tan, Mayassa B. Dargham, Jun S. Liu, Ty Lively, Cedric Sheffield. Personalized chemotherapy regimen selection for breast cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2034.

Catheter Ablation for Atrial Arrhythmias in Patients With CABackgroundCardiac amyloidosis (CA) is associated with increased atrial arrhythmias risk. The efficacy/safety of catheter‐based ablation therapy in patients with CA has not been adequately assessed.Methods and ResultsAll diagnosed CA patients who underwent atrial arrhythmia ablation therapy from 1995 to 2015 were reviewed. Arrhythmia recurrence, NYHA symptoms, and mortality were recorded. A total of 26 patients with CA and atrial arrhythmias were included; there were 7 light‐chain (AL), 17 wild‐type transthyretin (ATTRwt), and 2 mutated transthyretin (ATTRm) amyloidosis patients in total. Of which 13 underwent atrial arrhythmia ablation (CA‐A) and 13 underwent AV nodal ablation (CA‐AVN). In the CA‐A group, there were: 3 with atrial fibrillation (AF); 6 with atrial flutter (AFL); 2 with AF/AFL; and 2 with atrial tachycardia (AT). One‐year and 3‐year recurrence‐free survival were 75% and 60%, respectively. NYHA symptom improvement 6 months postablation was observed in both CA‐A and CA‐AVN groups: 7/10 (70%) and 4/8 (50%), respectively. Eleven patients with CA died (8 in CA‐AVN group vs. 3 in CA‐A group).ConclusionsCatheter‐based ablation for patients with CA appears to provide important symptomatic relief. However, mortality from the underlying disease remains a significant issue for the amyloid light‐chain subtype.

OBJECTIVE An increasing number of patients with poor-grade aneurysmal subarachnoid hemorrhage (aSAH) have received endovascular treatment. Endovascular treatment of poor-grade aSAH, however, is based on single-center retrospective studies, and predictors of long-term outcome have not been well defined. Using results from a multicenter prospective registry, the authors aimed to develop preoperative and postoperative prognostic models to predict poor outcome after endovascular treatment of poor-grade aSAH. METHODS A Multicenter Poor-grade Aneurysm Study (AMPAS) was a prospective and observational registry of consecutive patients with poor-grade aSAH. From October 2010 to March 2012, 366 patients were enrolled in the registry, and 136 patients receiving endovascular treatment were included in this study. Outcome was assessed by modified Rankin Scale (mRS) score at 12 months, and poor outcome was defined as an mRS score of 4, 5, or 6. Prognostic models were developed in multivariate logistic regression models. The area under receiver operating characteristic curves (AUC) was used to assess the model's discriminatory ability, and Hosmer-Lemeshow goodness-of-fit tests were used to assess the calibration. RESULTS At 12 months, 64 patients (47.0%) had a poor outcome: 9 (6.6%) had an mRS score of 4, 6 (4.4%) had an mRS score of 5, and 49 (36.0%) had died. Univariate analyses showed that older age (p = 0.001), female sex (p = 0.044), lower Glasgow Coma Scale score (p < 0.001), a World Federation of Neurosurgical Societies (WFNS) grade of V (p < 0.001), higher Fisher grade (p < 0.001), modified Fisher grade (p < 0.001), and wider neck aneurysm (p = 0.026) were associated with a poor outcome. There was a trend toward a worse outcome in patients with anterior communicating artery aneurysms (p = 0.080) and in those with incompletely occluded aneurysms (p = 0.063). After endovascular treatment, the presence of cerebral infarction (p = 0.039), symptomatic vasospasm (p = 0.039), and pneumonia (p = 0.006) were associated with a poor outcome. Multivariate analyses showed that the preoperative prognostic model including age, a WFNS grade of V, modified Fisher grade, and aneurysm neck size had excellent discrimination with an AUC of 0.86 (95% CI 0.80–0.92, p < 0.001), and a postoperative model that included these predictors as well as postoperative pneumonia had excellent discrimination (AUC = 0.87, 95% CI 0.81–0.93, p < 0.001). Both models had good calibration (p = 0.941 and p = 0.653, respectively). CONCLUSIONS Older age, WFNS Grade V, higher modified Fisher grade, wider neck aneurysm, and postoperative pneumonia were independent predictors of poor outcome after endovascular treatment of poor-grade aSAH. The preoperative model had almost the same discrimination as the postoperative model. Endovascular treatment should be carefully considered in patients with poor-grade aSAH with ruptured wide-neck aneurysms. ▪ CLASSIFICATION OF EVIDENCE Type of question: prognostic; study design: retrospective cohort trial; evidence: Class I.

Abstract Ten case reports of disseminated Mycobacterium chimaera infections associated with cardiovascular surgery were published from Europe. We report 3 cases of disseminated M chimaera infections with histories of aortic graft and/or valvular surgery within the United States. Two of 3 patients demonstrated ocular involvement, a potentially important clinical finding.

Abstract The addition of trastuzumab to chemotherapy extends survival among patients with HER2+ breast cancer. Prior work showed that trastuzumab and chemotherapy augments HER2 extracellular domain (ECD)-specific antibodies. The current study investigated whether combination therapy induced immune responses beyond HER2-ECD and, importantly, whether those immune responses were associated with survival. Pretreatment and posttreatment sera were obtained from 48 women with metastatic HER2+ breast cancer on NCCTG (now Alliance for Clinical Trials in Oncology) studies, N0337 and N983252. IgG to HER2 intracellular domain (ICD), HER2-ECD, p53, IGFBP2, CEA, and tetanus toxoid were examined. Sera from 25 age-matched controls and 26 surgically resected HER2+ patients were also examined. Prior to therapy, some patients with metastatic disease had elevated antibodies to IGFBP2, p53, HER2-ICD, HER2-ECD, and CEA, but not to tetanus toxin, relative to controls and surgically resected patients. Treatment augmented antibody responses to HER2-ICD in 69% of metastatic patients, which was highly associated with improved progression-free survival (PFS; HR = 0.5, P = 0.0042) and overall survival (OS; HR = 0.7, P = 0.038). Augmented antibody responses to HER2-ICD also correlated (P = 0.03) with increased antibody responses to CEA, IGFBP2, and p53, indicating that treatment induces epitope spreading. Paradoxically, patients who already had high preexisting immunity to HER2-ICD did not respond to therapy with increased antibodies to HER2-ICD and demonstrated poorer PFS (HR = 1.6, P &lt; 0.0001) and OS (HR = 1.4, P = 0.0006). Overall, the findings further demonstrate the importance of the adaptive immune system in the efficacy of trastuzumab-containing regimens. Cancer Res; 76(13); 3702–10. ©2016 AACR.

A 39-year-old male, who recently underwent a composite valve graft of the aortic root and ascending aorta for bicuspid aortic valve and aortic root aneurysm, was hospitalized for severe sepsis, rhabdomyolysis (creatine kinase 29000 U/L), and severe liver dysfunction (AST > 7000 U/L, ALT 4228 U/L, and INR > 10). Cardiac magnetic resonance imaging (MRI) findings were consistent with sternal osteomyelitis with a 1.5 cm abscess at the inferior sternotomy margin, which was contiguous with pericardial thickening. Aspiration and culture of this abscess did not yield any organisms, so he was treated with vancomycin and cefepime empirically for 4 weeks. Because this patient was improving clinically on antibiotics and did not show external signs of wound infection, there was no compelling indication for sternectomy. This patient’s unusual presentation with osteomyelitis and rhabdomyolysis has never been reported and is crucial for clinicians to recognize in order to prevent delays in diagnosis.