The International Consortium on Primary Graft Dysfunction: Redefining Clinical Risk Factors in the Contemporary Era of Heart Transplantation.

BACKGROUND: Primary graft dysfunction (PGD) is the leading cause of morbidity and mortality early after heart transplantation (HT). The International Consortium on PGD is a multicenter collaboration dedicated to identifying the clinical risk factors for PGD in the contemporary era of HT. The objectives of the current report were (1) to assess the incidence of severe PGD in an international cohort; (2) to evaluate the performance of the most strongly validated PGD risk tool, the RADIAL score, in a contemporary cohort; and (3) to redefine clinical risk factors for severe PGD in the current era of HT. METHODS: This is a retrospective, observational study of consecutive adult HT recipients between 2010 and 2020 in 10 centers in the United States, Canada and Europe. Patients with severe PGD were compared to those without severe PGD (comprising those with no, mild and moderate PGD). The RADIAL score was calculated for each transplant recipient. The discriminatory power of the RADIAL score was evaluated using receiver operating characteristic (ROC) analysis, and its calibration was assessed by plotting the percentage of PGD predicted vs that which was observed. To identify clinical risk factors associated with severe PGD, we performed multivariable mixed-effects logistic regression modeling to account for among-center variability. RESULTS: A total of 2746 patients have been enrolled in the registry to date, including 2015 (73.4%) from North America, and 731 (26.6%) from Europe; 215 participants (7.8%) met the criteria for severe PGD. There was an increase in the incidence of severe PGD over the study period (P value for trend by difference sign test = 0.004). The Kaplan-Meier estimate for 1-year survival was 75.7% (95% CI 69.4-80.9%) in patients with severe PGD as compared to 94.4% (95% CI 93.5-95.2%) in those without severe PGD (log-rank P value < 0.001). The RADIAL score performed poorly in our contemporary cohort and was not associated with severe PGD; it had an AUC of 0.53 (95% CI 0.48-0.58). In the multivariable regression model, acute preoperative dialysis (OR 2.41, 95% CI 1.31-4.43), durable left ventricular assist device support (OR 1.77, 95% CI 1.13-2.77), and total ischemic time (OR 1.20 for each additional hour, 95% CI 1.02-1.41) were associated with an increased risk of severe PGD. CONCLUSIONS: Our consortium has identified an increasing incidence of PGD in the modern transplant era. We identified contemporary risk factors for this early post-transplant complication, which confers a high mortality risk. These results may enable the identification of patients at high risk for developing severe PGD in order to inform peri-transplant donor and recipient management practices.

Identification of risk epitope mismatches associated with de novo donor-specific HLA antibody development in cardiothoracic transplantation.

The development of de novo donor-specific HLA antibodies (dnDSA) after transplantation is associated with graft failure, mortality, and cost. There is no effective therapeutic intervention to prevent dnDSA or ameliorate associated injury. The aims of this study were to identify specific HLA factors associated with dnDSA development and to propose primary prevention strategies that could reduce the incidence of dnDSA without prohibitively limiting access to transplant. The investigation cohort included heart transplant recipients from 2008 to 2015 (n = 265). HLA typing was performed and HLA antibody testing was undertaken before and after transplantation. HLAMatchmaker analysis was performed for persistent dnDSA to identify potentially more immunogenic eplet differences. Validation was performed in recipients of lung transplants from 2008 to 2013 (n = 433). The majority of recipients with dnDSA had antibodies to identical eplet positions on DQ2 and DQ7. A high-risk epitope mismatch (found in DQA1*05 +  DQB1*02/DQB1*03:01(7)) was associated with a 4.2- and 4.9-fold increased risk of dnDSA in heart and lung recipients respectively. HLA electrostatic potential modeling provided a plausible explanation for this observed immunogenicity. A theoretical allocation algorithm avoiding high-risk epitope mismatches was generated and predicted to reduce dnDSA by up to 72% without additional testing, eplet analysis, or cost.

Incidence of brain metastasis from esophageal cancer.

We investigated whether the incidence of brain metastasis (BM) from primary esophageal and esophagogastric cancer is increasing. A single-institution retrospective review identified 583 patients treated from January 1997 to January 2016 for stages I through IV cancer of the esophagus and esophagogastric junction (follow-up, ≥3 months). Collected data included demographic information, date and staging at primary diagnosis, histologic subtype, treatment regimen for primary lesion, date of BM diagnosis, presence or absence of central nervous system symptoms, presence or absence of extracranial disease, treatment regimen for intracranial lesions, and date of death. The overall cohort included 495 patients (85%) with adenocarcinoma and 82 (14%) with squamous cell carcinoma (492 [84%] were male; median age at diagnosis, 68 years [range: 26-90 years]). BM was identified in 22 patients (3.8%) (median latency after primary diagnosis, 11 months). Among patients with BM, the primary histology was adenocarcinoma in 21 and squamous cell carcinoma in 1 (P = 0.30). BM developed in 12 who were initially treated for locally advanced disease and in 10 stage IV patients who presented with distant metastases. Overall survival (OS) after BM diagnosis was 18% at 1 year (median, 4 months). No difference in OS after BM diagnosis was observed in patients initially treated for localized disease compared to patients who presented with stage IV disease; however, OS was superior for patients who initially had surgical resection compared to patients treated with whole brain radiotherapy or stereotactic radiosurgery alone (1-year OS, 67% vs. 0%; median OS, 13.5 vs. 3 months; P = 0.003). The incidence of BM is low in patients with esophageal cancer. Outcomes were poor overall for patients with BM, but patients who underwent neurosurgical resection had improved survival.

Perfusion Cardiac Magnetic Resonance Imaging as a Rule-Out Test for Cardiac Allograft Vasculopathy.

Cardiac allograft vasculopathy (CAV) is a leading cause of mortality after heart transplantation. Noninvasive imaging techniques used in CAV evaluation have important limitations. In a cross-sectional study, we investigated perfusion cardiac magnetic resonance (CMR) imaging to determine an optimal myocardial perfusion reserve index (MPR) cutoff for detecting CAV using receiver operating characteristic curve analysis. We evaluated CMR performance using sensitivity, specificity and likelihood ratio analysis. We included 29 patients (mean 5 ± 4 years after transplant) scheduled for coronary angiography with intravascular ultrasound (IVUS) who completed CMR. CAV was defined as maximal intimal thickness (MIT) >0.5 mm by IVUS of the left anterior descending artery. CAV was evident in 19 patients (70%) on IVUS (mean MIT 0.82 ± 0.42 mm). MPR was significantly lower in patients with MIT ≥0.50 mm (1.35 ± 0.23 vs. 1.71 ± 0.45, p = 0.013). There was moderate inverse correlation between MPR and MIT (r = -0.36, p = 0.075). The optimal MPR cutoff ≤1.68 for predicting CAV showed sensitivity of 100%, specificity of 63%, a negative predictive value of 100%, a positive predictive value of 86% and a positive likelihood ratio of 2.7. An MPR ≤1.68 has high negative predictive value, suggesting its potential as a test to rule out CAV.

Retransplant and Medical Therapy for Cardiac Allograft Vasculopathy: International Society for Heart and Lung Transplantation Registry Analysis.

Cardiac retransplantation for heart transplant recipients with advanced cardiac allograft vasculopathy (CAV) remains controversial. The International Society for Heart and Lung Transplantation Registry was used to examine survival in adult heart recipients with CAV who were retransplanted (ReTx) or managed medically (MM). Recipients transplanted between 1995 and 2010 who developed CAV and were either retransplanted within 2 years of CAV diagnosis (ReTx) or alive at ≥2 years after CAV diagnosis, managed medically (MM), without retransplant, constituted the study groups. Donor, recipient, transplant characteristics and long-term survival were compared. The population included 65 patients in ReTx and 4530 in MM. During a median follow-up of 4 years, there were 24 deaths in ReTx, and 1466 in MM. Survival was comparable at 9 years (55% in ReTx and 51% in MM; p = 0.88). Subgroup comparison suggested survival benefit for retransplant versus MM in patients who developed systolic graft dysfunction. Adjusted predictors for 2-year mortality were diagnosis of CAV in the early era and longer time since CAV diagnosis following primary transplant. Retransplant was not an independent predictor in the model. Challenges associated with retransplantation as well as improved CAV treatment options support the current consensus recommendation limiting retransplant to highly selected patients with CAV.

Incidence and impact of postoperative atrial fibrillation after minimally invasive esophagectomy.

Atrial fibrillation (AF) following open esophagectomy has been associated with increased rates of pulmonary and anastomotic complications, and mortality. This study seeks to evaluate effects of AF after minimally invasive esophagectomy (MIE). A retrospective review of patients consecutively treated with MIE for esophageal carcinoma, dysplasia. and benign disease from November 2006 to November 2011 was performed. One hundred twenty-one patients underwent MIE. Median age was 65 years (range 26-88) with 85% being male. Thirty-eight (31.4%) patients developed AF postoperatively. Of these 38 patients, 7 (18.4%) had known AF preoperatively. Patients with postoperative AF were significantly older than those without postoperative AF (68.7 vs. 62.8 years, P = 0.008) and more likely to be male (94.7% vs. 80.7%, P = 0.04). Neoadjuvant chemoradiation showed a trend toward increased risk of AF (73.7% vs 56.6%, P = 0.07). Sixty-day mortality was 2 of 38 (5.3%) in patients with AF and 4 of 83 (6.0%) in the no AF cohort (P = 1.00). The group with AF had increased length of hospitalization (13.4 days vs. 10.6 days P = 0.02). No significant differences in rates of pneumonia (31.6% vs. 21.7% P = 0.24), stricture (13.2% vs. 26.5% P = 0.10), or leak requiring return to operating room (13.2% vs. 8.4% P = 0.51) were noted between groups. We did not find an increased rate of AF in our MIE cohort compared with prior reported rates in open esophagectomy populations. AF did result in an increased length of stay but was not a predictor of other short-term morbidities including anastomotic leak, pulmonary complications, stenosis, or 60-day mortality.

Randomized phase II trial of pemetrexed/cisplatin with or without CBP501 in patients with advanced malignant pleural mesothelioma.

BACKGROUND: CBP501, a synthetic duodecapeptide, increases cisplatin influx into tumor cells through an interaction with calmodulin enhancing cisplatin cytotoxicity, and effects cell cycle progression by abrogating DNA repair at the G2 checkpoint. In phase I clinical trials of CBP501 alone or in combination with cisplatin, the most common toxicity was infusion-related urticaria. Activity of CBP501 plus cisplatin was observed in patients with ovarian cancer and mesothelioma, including some patients previously treated with cisplatin. METHODS: Chemotherapy naïve patients with unresectable MPM were stratified by histology and performance status, and randomized 2:1 to pemetrexed/cisplatin plus CBP501 25mg/m(2) IV (Arm A) or pemetrexed/cisplatin alone (Arm B). The primary endpoint was progression free survival (PFS) at 4 months. RESULTS: 65 patients were randomized, and 63 were treated. Patient characteristics in the two arms were balanced. Based on independent radiology review of the treated population, 25/40 patients (63%) in Arm A and 9/23 (39%) in Arm B had PFS≥4mo; the median PFS was 5.1mo (95% CI, 3.9, 6.5) vs 3.4mo (2.5, 6.7). Median OS was 13.3mo (9.2, 16.3) in Arm A and 12.8 (6.5, 16.1) in Arm B. Adverse events were not different than expected from standard chemotherapy, and comparable in the two arms, aside from infusion reactions which occurred in 70% of patients treated with CBP501. CONCLUSIONS: While this randomized phase II trial met its primary endpoint of PFS at 4 months, other parameters such as response rate and overall survival suggest that the addition of CBP501 does not improve the efficacy of standard chemotherapy for MPM.

A survey of current practice for antibody-mediated rejection in heart transplantation.

No evidence based management guidelines exist for antibody mediated rejection (AMR) in heart transplantation. The International Society for Heart and Lung Transplantation (ISHLT) recently introduced standardized pathologic based diagnostic criteria for AMR (pAMR 0-3). We evaluated international practice for the management of AMR focusing on pAMR grade, donor specific antibody (DSA) and allograft function. On-line survey data were analyzed from 184 ISHLT members (physicians-78%, surgeons-20%). The majority were from adult-transplant (84%), medium-large volume centres (transplants/year: 10-25, 61%; 25-50, 19%) across North America (60%) and Europe (26%). Irrespective of pAMR grade and DSA, 83-90% treated a drop in ejection fraction (EF≤45% or >25% decrease). In the presence of stable EF, an increasing number elected treatment for progressively severe pAMR grade (p<0.001) and for accompanying DSA (p<0.05, pAMR 1-3). Intravenous steroid was the most commonly used therapy followed by intravenous immunoglobulin (IVIG) or plasmapheresis, rituximab and thymoglobulin. Plasmapheresis and rituximab were favored for positive versus negative DSA (p<0.05). Using a threshold of ≥70% consensus among respondents, treatment for AMR may be considered for a drop in EF, asymptomatic pAMR 3 or asymptomatic pAMR 2 with DSA. Combination steroid, IVIG and plasmapheresis are suggested as initial therapies.

Prophylactic cranial irradiation in small-cell lung cancer: findings from a North Central Cancer Treatment Group Pooled Analysis.

BACKGROUND: This pooled analysis evaluated the outcomes of prophylactic cranial irradiation (PCI) in 739 small-cell lung cancer (SCLC patients with stable disease (SD) or better following chemotherapy ± thoracic radiation therapy (TRT) to examine the potential advantage of PCI in a wider spectrum of patients than generally participate in PCI trials. PATIENTS AND METHODS: Three hundred eighteen patients with extensive SCLC (ESCLC) and 421 patients with limited SCLC (LSCLC) participated in four phase II or III trials. Four hundred fifty-nine patients received PCI (30 Gy/15 or 25 Gy/10) and 280 did not. Survival and adverse events (AEs) were compared. RESULTS: PCI patients survived significantly longer than non-PCI patients {hazard ratio [HR] = 0.61 [95% confidence interval (CI): 0.52-0.72]; P < 0.0001}. The 1- and 3-year survival rates were 56% and 18% for PCI patients versus 32% and 5% for non-PCI patients. PCI was still significant after adjusting for age, performance status, gender, stage, complete response, and number of metastatic sites (HR = 0.82, P = 0.04). PCI patients had significantly more grade 3+ AEs (64%) compared with non-PCI patients (50%) (P = 0.0004). AEs associated with PCI included alopecia and lethargy. Dose fractionation could be compared only for LSCLC patients and 25 Gy/10 was associated with significantly better survival compared with 30 Gy/15 (HR = 0.67, P = 0.018). CONCLUSIONS: PCI was associated with a significant survival benefit for both ESCLC and LSCLC patients who had SD or a better response to chemotherapy ± TRT. Dose fractionation appears important. PCI was associated with an increase in overall and specific grade 3+ AE rates.

Atrial masses post cardiac transplantation: diagnostic and treatment dilemmas.

Atrial masses postcardiac transplant are not well reported and their diagnosis and treatment can be challenging. In the asymptomatic patient, differentiating thrombus from cardiac tumor can sometimes be difficult and the use of multiple imaging modalities is recommended. Accurate diagnosis is imperative to inform a treatment plan that balances the benefits and risks of a medical versus surgical approach. We present three cases of atrial masses postcardiac transplant to illustrate this clinical dilemma.

A phase I trial of pan-Bcl-2 antagonist obatoclax administered as a 3-h or a 24-h infusion in combination with carboplatin and etoposide in patients with extensive-stage small cell lung cancer.

BACKGROUND: Bcl-2 family genes are frequently amplified in small cell lung cancer (SCLC). A phase I trial was conducted to evaluate the safety of obatoclax, a Bcl-2 family inhibitor, given in combination with standard chemotherapy. METHODS: Eligible patients (3-6 per cohort) had extensive-stage SCLC, measurable disease, ≤ 1 before therapy, Eastern Cooperative Oncology Group performance status 0 or 1, and adequate organ function. Patients were treated with escalating doses of obatoclax, either as a 3- or 24-h infusion, on days 1-3 of a 21-day cycle, in combination with carboplatin (area under the curve 5, day 1 only) and etoposide (100 mg m(-2), days 1-3). The primary endpoint was to determine the maximum tolerated dose of obatoclax. RESULTS: Twenty-five patients (56% male; median age 66 years) were enrolled in three dose cohorts for each schedule. Maximum tolerated dose was established with the 3-h infusion at 30 mg per day and was not reached with the 24-h infusion. Compared with the 24-h cohorts, the 3-h cohorts had higher incidence of central nervous system (CNS) adverse events (AEs); dose-limiting toxicities were somnolence, euphoria, and disorientation. These CNS AEs were transient, resolving shortly after the end of infusion, and without sequelae. The response rate was 81% in the 3-h and 44% in the 24-h infusion cohorts. CONCLUSION: Although associated with a higher incidence of transient CNS AEs than the 24-h infusion, 3-h obatoclax infusion combined with carboplatin-etoposide was generally well tolerated at doses of 30 mg per day. Though patient numbers were small, there was a suggestion of improved efficacy in the 3-h infusion group. Obatoclax 30 mg infused intravenously over 3 h on 3 consecutive days will be utilised in future SCLC studies.

Factors associated with the development of cardiac allograft vasculopathy--a systematic review of observational studies.

Cardiac allograft vasculopathy (CAV) is a significant factor impacting outcomes after heart transplant. We performed a systematic review of risk factors for the development of CAV. A search of electronic databases was performed. The eligibility criteria included cohort and case-control studies with more than 50 adult patients submitted to a heart transplant. The outcome should be CAV diagnosed by angiography and/or intravascular ultrasound (IVUS). Two reviewers performed study selection, data abstraction, and quality assessment. Of 2514 citations, 66 articles were included--46 had 200 participants or less; 61 were single-center; and 44 were retrospective cohorts. The most used definition of CAV using angiography was the detection of any degree of abnormality (21 studies of 58). In studies using IVUS, an intimal thickness ≥0.5 mm was the most used definition (five of eight studies). Quality assessment revealed an inadequate description of patient selection, attrition, and accounting of potential confounders. Donor age, recipient age, recipient gender, etiology of heart failure, ischemic time, human leukocyte antigen matching, cytomegalovirus, lipid profile, and rejection episodes were the most studied factors. Our review indicates that the current evidence is not consistent across different studies. The definite contribution of risk factors for the development of CAV is still to be determined.

Impact of adjuvanted H1N1 vaccine on cell-mediated rejection in heart transplant recipients.

During the H1N1 influenza virus pandemic, vaccination of high risk groups including solid-organ transplant recipients was advised. A retrospective case control study of 60 heart transplant patients, 15 having received the H1N1 virus antigen and ASO3 adjuvant vaccine (GlaxoSmithKline, Mississauga, ON, Canada) within 21 days and 45 having not been vaccinated, all undergoing routine surveillance endmyocardial biopsies, was performed. The overall rate of cellular rejection (all grades) was not statistically different between groups; however, acute cellular rejection, ≥grade 2 (1990 ISHLT criteria), was more frequent among those having recently vaccinated (control: 1/45 vs. 6/15, p = 0.001). On multivariate analysis, the only risk factor found to be associated with acute cellular rejection was recent H1N1 viral antigen and adjuvant vaccination (OR 26.5: 95% CI 02.59-270.5). Vaccine adjuvants increase host response to vaccine antigens by immune upregulation potentially increasing risk of rejection in solid-organ transplant recipients. The potential hazard of vaccination this study raises must be weighed with the clear benefit vaccination has proven to be.

The obligation to say 'Thank you': heart transplant recipients' experience of writing to the donor family.

Transplant recipients are encouraged to write anonymous thank-you letters to the donor family. We prospectively explored heart transplant recipients' embodied responses to the 'obligation' to write a thank-you letter using audio/video-taped open-ended interviews (N = 27). Fifteen of the 19 participants, who wrote letters to the donor family, expressed or visually revealed significant distress about issues such as the obligation to write anonymously and the inadequacy of the 'thank-you'. Writing the thank-you letter is not a neutral experience for heart transplant recipients. Rethinking the obligatory practice regarding the thank-you letter and developing the necessary support for the recipient through this process is necessary.

Sirolimus is associated with impaired hematopoiesis in heart transplant patients? A retrospective analysis.

BACKGROUND: Proliferation signal inhibitors may adversely impact bone marrow function. We sought to describe the impact of sirolimus on hemoglobin and erythropoiesis in heart transplant recipients. METHODS: We have conducted a single-center, retrospective analysis of all heart transplant patients treated with sirolimus. We measured serum hemoglobin (Hb) at baseline and at 3 months to determine the prevalence of anemia and change in Hb after sirolimus initiation. We also characterized hematologic profile of patients to gain insights into the effects of sirolimus on erythropoiesis. RESULTS: There were 84 patients included in the study. The prevalence of anemia increased from 71% to 75% after sirolimus initiation. Anemic patients were more likely to be male (P = .026) and have worse renal function (glomerular filtration rate 49 ± 27 vs 70 ± 42 mL/min; P = .012). A ≥20 g/L drop in Hb was observed in 25% of the overall cohort. Patients investigated for anemia (n = 67) had a low Hb (111 ± 24 g/L), normal mean corpuscular volume (87 ± 47 FL), and low serum iron levels (10 ± 5 µmol/L) and transferrin saturation (0.22 ± 0.12). Serum ferritin was variable (263 ± 370 µg/L). Bone marrow evaluation in 19 patients revealed adequate marrow iron stores in all cases. CONCLUSION: Anemia is prevalent in heart transplant patients treated with sirolimus and increases over time. Patients have a characteristic hematologic profile suggestive of anemia of chronic disease and functional iron deficiency.

Community support of patients with a left ventricular assist device: The Toronto General Hospital experience.

BACKGROUND: Implantation of a left ventricular assist device (LVAD) is an acceptable therapy for patients with advanced heart failure. LVADs may be used as a bridge to recovery, a bridge to transplantation or as destination therapy. Although the morbidity rate of individuals on device support remains high, experience suggests that patients who are discharged home have satisfactory outcomes during support and following heart transplantation. METHODS: A retrospective review of 24 patients implanted with an LVAD between October 2001 and December 2006 was performed. Nineteen patients received a device as a bridge to transplantation and five received a device as destination therapy. Postoperative follow-up was performed routinely in the heart function/LVAD clinic at the Toronto General Hospital (Toronto, Ontario) and all adverse events were recorded. RESULTS: The majority of patients were men, with a mean age of 44 years and a diagnosis of dilated cardiomyopathy (62%). Seventeen patients (71%) were discharged home on support; one died, 14 were transplanted, one was explanted and one patient remains on support in the community. Post-transplant survival was 93% in patients discharged home compared with 40% transplanted during their hospital stay. Outpatients spent 56% of their overall support time at home, with only 12 readmissions totalling 120 patient days. CONCLUSIONS: LVAD patients can be safely managed in the community. Patients who are discharged home experience better outcomes in both pre- and post-transplant survival. Successful outpatient management provides a strong foundation for the establishment of destination therapy within mechanical circulatory support programs in Canada.

Mitral valve-sparing procedures and prosthetic heart valve failure: a case report.

Prosthetic heart valve dysfunction due to thrombus or pannus formation can be a life-threatening complication. The present report describes a 47-year-old woman who developed valvular cardiomyopathy after chorda-sparing mitral valve replacement, and subsequently underwent heart transplantation for progressive heart failure. The explanted mitral valve prosthesis showed significant thrombus and pannus leading to reduced leaflet mobility and valvular stenosis. The present report illustrates the role of the subvalvular apparatus and pannus in prosthesis dysfunction.

Selective dose escalation of chemoradiotherapy for locally advanced esophageal cancer.

This phase II study assessed the use of concurrent continuous infusion of 5-fluorouracil and weekly carboplatin plus paclitaxel with selective radiation dose escalation for patients with localized esophageal cancer. Patients with esophageal carcinoma were staged by thoracic and abdominal computed tomography, endoscopic ultrasound, and positron emission tomography scans. Patients received a continuous infusion of 5-fluorouracil 225 mg/m(2) on days 1 to 38 and intravenous paclitaxel 45 mg/m(2) and carboplatin AUC 2 on days 1, 8, 15, 22, 29, and 36. Radiotherapy was delivered in 1.8-Gy fractions, 5 d/wk for 5.5 weeks. Six to 8 weeks after initial therapy, patients without metastatic progression but with a positive biopsy, or less than partial response received a 9-Gy boost with the same concurrent chemotherapy. Twenty-four patients were enrolled: 18 patients were enrolled initially; 6 additional patients were enrolled following a protocol amendment designed to reduce the esophagitis by adding the radioprotectant amifostine. Median follow-up was 30 months. Twenty (83%) patients had adenocarcinomas of the lower esophagus/gastroesophageal junction. Seventeen patients (81%) attained at least a partial response. Six patients received boost treatment. At 4 years, overall survival was 28%, cause-specific survival was 38%, locoregional control was 61%, and distant metastasis-free survival was 52%. Radiation delays ranged from 0 to 62 days (median, 8 d), primarily owing to esophagitis. In total, 28% of patients developed esophageal strictures requiring dilatations. There were no differences in esophageal strictures, local control, or survival with the addition of amifostine.

mTOR inhibition induces endothelial progenitor cell death.

Immunosuppressants are necessary to prevent graft rejection after solid organ transplantation. However, they are also known to have significant side effects, including endothelial toxicity. Endothelial progenitor cells originate in the bone marrow and are recognized by their angiogenic and endothelial reparative properties. The effects of the immunosuppressants cyclosporine A (CyA), tacrolimus and rapamycin were analyzed on endothelial progenitor-like cells. Rapamycin induced rapid cell death, even at concentrations much lower than those used clinically, in peripheral blood mononuclear cells (PBMC) cultured to favor outgrowth of endothelial progenitors. Cyclosporine A and tacrolimus had no significant effects at clinical concentrations. The effect of rapamycin was specific to endothelial progenitor cells, in particular to the early stages of differentiation, as a lesser effect was observed in late outgrowth endothelial progenitors, mature aortic endothelial cells, and macrophages derived from the same PBMCs. The mechanism of cell death appeared to be apoptosis; however, its induction was probably multifactorial and did not depend on caspase or cathepsin activation. In conclusion, rapamycin induces endothelial progenitor cell death, possibly because it blocks survival signals given by growth factors critically required by these cells.

Neuroendocrine-like differentiation of non-small cell lung carcinoma cells: regulation by cAMP and the interaction of mac25/IGFBP-rP1 and 25.1.

The need to develop more effective therapies for lung cancer has led to investigations in understanding the molecular mechanisms of the differentiation process, in particular neuroendocrine (NE) differentiation. Recent studies have demonstrated that NE differentiation in non-small cell lung carcinoma (NSCLC) is not uncommon. Those NSCLCs with NE differentiation are considered a form of in transition NE carcinoma and show a more aggressive clinical course compared with NSCLC without NE differentiation. 25.1, a novel protein interacting with mac25/insulin-like growth factor-binding protein-related protein 1 (mac25/IGFBP-rP1), induced NE-like differentiation when collectively overexpressed in M12 prostate cancer cells. We have examined mac25/IGFBP-rP1 and 25.1 as potential molecular regulators in vitro of the NE-differentiation process in lung cancer. In a panel of SCLC and NSCLC cell lines, mac25/IGFBP-rP1 and 25.1 were expressed at higher levels in SCLC. An increase and sustained activation of adenosine 3',5'-cyclic monophosphate (cAMP) levels induced NE-like differentiation in NSCLC cell lines, and a concomitant increase in the expression of mac25/IGFBP-rP1 and 25.1 was observed during the cAMP-regulated differentiation of NCI-H157 cells, suggesting the involvement of these proteins. Furthermore, the collective overexpression of mac25/IGFBP-rP1 and 25.1 in NSCLC cells induced NE-like differentiation as early as 6 h postinfection. The present data suggest that mac25/IGFBP-rP1 and 25.1 may play a functional role in the NE differentiation of NSCLC cell lines and may provide a novel therapeutic target for treating lung cancers, in particular NSCLC with NE differentiation.