Autophagy is Involved in Cardiac Remodeling in Response to Environmental Temperature Change

Objectives: To study the reversibility of cold-induced cardiac hypertrophy and the role of autophagy in this process. Background: Chronic exposure to cold is known to cause cardiac hypertrophy independent of blood pressure elevation. The reversibility of this process and the molecular mechanisms involved are unknown. Methods: Studies were performed in two-month-old mice exposed to cold (4°C) for 24 h or 10 days. After exposure, the animals were returned to room temperature (21°C) for 24 h or 1 week. Results: We found that chronic cold exposure significantly increased the heart weight/tibia length (HW/TL) ratio, the mean area of cardiomyocytes, and the expression of hypertrophy markers, but significantly decreased the expression of genes involved in fatty acid oxidation. Echocardiographic measurements confirmed hypertrophy development after chronic cold exposure. One week of deacclimation for cold-exposed mice fully reverted the morphological, functional, and gene expression indicators of cardiac hypertrophy. Experiments involving injection of leupeptin at 1 h before sacrifice (to block autophagic flux) indicated that cardiac autophagy was repressed under cold exposure and re-activated during the first 24 h after mice were returned to room temperature. Pharmacological blockage of autophagy for 1 week using chloroquine in mice subjected to deacclimation from cold significantly inhibited the reversion of cardiac hypertrophy. Conclusion: Our data indicate that mice exposed to cold develop a marked cardiac hypertrophy that is reversed after 1 week of deacclimation. We propose that autophagy is a major mechanism underlying the heart remodeling seen in response to cold exposure and its posterior reversion after deacclimation.

Allogeneic Transplantation to Treat Therapy-Related Myelodysplastic Syndrome and Acute Myelogenous Leukemia in Adults

Patients who develop therapy-related myeloid neoplasm, either myelodysplastic syndrome (t-MDS) or acute myelogenous leukemia (t-AML), have a poor prognosis. An earlier Center for International Blood and Marrow Transplant Research (CIBMTR) analysis of 868 allogeneic hematopoietic cell transplantations (allo-HCTs) performed between 1990 and 2004 showed a 5-year overall survival (OS) and disease-free survival (DFS) of 22% and 21%, respectively. Modern supportive care, graft-versus-host disease prophylaxis, and reduced-intensity conditioning (RIC) regimens have led to improved outcomes. Therefore, the CIBMTR analyzed 1531 allo-HCTs performed in adults with t-MDS (n = 759) or t-AML (n = 772) between and 2000 and 2014. The median age was 59 years (range, 18 to 74 years) for the patients with t-MDS and 52 years (range, 18 to 77 years) for those with t-AML. Twenty-four percent of patients with t-MDS and 11% of those with t-AML had undergone a previous autologous (auto-) HCT. A myeloablative conditioning (MAC) regimen was used in 49% of patients with t-MDS and 61% of patients with t-AML. Nonrelapse mortality at 5 years was 34% (95% confidence interval [CI], 30% to 37%) for patients with t-MDS and 34% (95% CI, 30% to 37%) for those with t-AML. Relapse rates at 5 years in the 2 groups were 46% (95% CI, 43% to 50%) and 43% (95% CI, 40% to 47%). Five-year OS and DFS were 27% (95% CI, 23% to 31%) and 19% (95% CI, 16% to 23%), respectively, for patients with t-MDS and 25% (95% CI, 22% to 28%) and 23% (95% CI, 20% to 26%), respectively, for those with t-AML. In multivariate analysis, OS and DFS were significantly better in young patients with low-risk t-MDS and those with t-AML undergoing HCT with MAC while in first complete remission, but worse for those with previous auto-HCT, higher-risk cytogenetics or Revised International Prognostic Scoring System score, and a partially matched unrelated donor. Relapse remains the major cause of treatment failure, with little improvement seen over the past 2 decades. These data mandate caution when recommending allo-HCT in these conditions and indicate the need for more effective antineoplastic approaches before and after allo-HCT.

Measuring interoception: The phase adjustment task

Interoception, perception of one's bodily state, has been associated with mental health and socio-emotional processes. However, several interoception tasks are of questionable validity, meaning associations between interoception and other variables require confirmation with new measures. Here we describe the novel, smartphone-based Phase Adjustment Task (PAT). Tones are presented at the participant's heart rate, but out of phase with heartbeats. Participants adjust the phase relationship between tones and heartbeats until they are synchronous. Data from 124 participants indicates variance in performance across participants which is not affected by physiological or strategic confounds. Associations between interoception and anxiety, depression and stress were not significant. Weak associations between interoception and mental health variables may be a consequence of testing a non-clinical sample. A second study revealed PAT performance to be moderately stable over one week, consistent with state effects on interoception.

Risk Factors for Graft-versus-Host Disease in Haploidentical Hematopoietic Cell Transplantation Using Post-Transplant Cyclophosphamide

Post-transplant cyclophosphamide (PTCy) has significantly increased the successful use of haploidentical donors with a relatively low incidence of graft-versus-host disease (GVHD). Given its increasing use, we sought to determine risk factors for GVHD after haploidentical hematopoietic cell transplantation (haplo-HCT) using PTCy. Data from the Center for International Blood and Marrow Transplant Research on adult patients with acute myeloid leukemia, acute lymphoblastic leukemia, myelodysplastic syndrome, or chronic myeloid leukemia who underwent PTCy-based haplo-HCT (2013 to 2016) were analyzed and categorized into 4 groups based on myeloablative (MA) or reduced-intensity conditioning (RIC) and bone marrow (BM) or peripheral blood (PB) graft source. In total, 646 patients were identified (MA-BM = 79, MA-PB = 183, RIC-BM = 192, RIC-PB = 192). The incidence of grade 2 to 4 acute GVHD at 6 months was highest in MA-PB (44%), followed by RIC-PB (36%), MA-BM (36%), and RIC-BM (30%) (P = .002). The incidence of chronic GVHD at 1 year was 40%, 34%, 24%, and 20%, respectively (P < .001). In multivariable analysis, there was no impact of stem cell source or conditioning regimen on grade 2 to 4 acute GVHD; however, older donor age (30 to 49 versus <29 years) was significantly associated with higher rates of grade 2 to 4 acute GVHD (hazard ratio [HR], 1.53; 95% confidence interval [CI], 1.11 to 2.12; P = .01). In contrast, PB compared to BM as a stem cell source was a significant risk factor for the development of chronic GVHD (HR, 1.70; 95% CI, 1.11 to 2.62; P = .01) in the RIC setting. There were no differences in relapse or overall survival between groups. Donor age and graft source are risk factors for acute and chronic GVHD, respectively, after PTCy-based haplo-HCT. Our results indicate that in RIC haplo-HCT, the risk of chronic GVHD is higher with PB stem cells, without any difference in relapse or overall survival.

Impact of type of reduced-intensity conditioning regimen on the outcomes of allogeneic haematopoietic cell transplantation in classical Hodgkin lymphoma

Reduced-intensity conditioning (RIC) allogeneic haematopoietic cell transplantation (allo-HCT) is a curative option for select relapsed/refractory Hodgkin lymphoma (HL) patients; however, there are sparse data to support superiority of any particular conditioning regimen. We analyzed 492 adult patients undergoing human leucocyte antigen (HLA)-matched sibling or unrelated donor allo-HCT for HL between 2008 and 2016, utilizing RIC with either fludarabine/busulfan (Flu/Bu), fludarabine/melphalan (Flu/Mel140) or fludarabine/cyclophosphamide (Flu/Cy). Multivariable regression analysis was performed using a significance level of <0·01. There were no significant differences between regimens in risk for non-relapse mortality (NRM) (P = 0·54), relapse/progression (P = 0·02) or progression-free survival (PFS) (P = 0·14). Flu/Cy conditioning was associated with decreased risk of mortality in the first 11 months after allo-HCT (HR = 0·28; 95% CI = 0·10-0·73; P = 0·009), but beyond 11 months post allo-HCT it was associated with a significantly higher risk of mortality, (HR = 2·46; 95% CI = 0·1.32-4·61; P = 0·005). Four-year adjusted overall survival (OS) was similar across regimens at 62% for Flu/Bu, 59% for Flu/Mel140 and 55% for Flu/Cy (P = 0·64), respectively. These data confirm the choice of RIC for allo-HCT in HL does not influence risk of relapse, NRM or PFS. Although no OS benefit was seen between Flu/Bu and Flu/Mel 140; Flu/Cy was associated with a significantly higher risk of mortality beyond 11 months from allo-HCT (possibly due to late NRM events).

Outcomes of rituximab-BEAM versus BEAM conditioning regimen in patients with diffuse large B cell lymphoma undergoing autologous transplantation

BACKGROUND

Although rituximab-based high-dose therapy is frequently used in diffuse large B cell lymphoma (DLBCL) patients undergoing autologous hematopoietic cell transplantation (auto-HCT), data supporting the benefits are not available. Herein, we report the impact of rituximab-based conditioning on auto-HCT outcomes in patients who have DLBCL.

METHODS

Using the Center for International Blood and Marrow Transplant Research (CIBMTR) registry, 862 adult DLBCL patients undergoing auto-HCT between 2003 and 2017 using BEAM (BCNU, etoposide, cytarabine, melphalan) conditioning regimen were included. All patients received frontline rituximab-containing chemoimmunotherapy and had chemosensitive disease pre-HCT. Early chemoimmunotherapy failure was defined as not achieving complete remission (CR) after frontline chemoimmunotherapy or relapse within 1 year of initial diagnosis. The primary outcome was overall survival (OS).

RESULTS

The study cohort was divided into 2 groups: BEAM (n = 667) and R-BEAM (n = 195). On multivariate analysis, no significant difference was seen in OS (P = .83) or progression-free survival (PFS) (P = .61) across the 2 cohorts. No significant association between the use of rituximab and risk of relapse (P = .15) or nonrelapse mortality (P = .12) was observed. Variables independently associated with lower OS included older age at auto-HCT (P < .001), absence of CR at auto-HCT (P < .001) and early chemoimmunotherapy failure (P < .001). Older age (P < .0002) and non-CR pre-HCT (P < .0001) were also associated with inferior PFS. There was no significant difference in early infectious complications between the 2 cohorts.

CONCLUSION

In this large registry analysis of DLBCL patients undergoing auto-HCT, the addition of rituximab to the BEAM conditioning regimen had no impact on transplantation outcomes. Older age, absence of CR pre auto-HCT, and early chemoimmunotherapy failure were associated with inferior survival.

Impact of T Cell Dose on Outcome of T Cell-Replete HLA-Matched Allogeneic Peripheral Blood Stem Cell Transplantation

Data on whether the T cell dose of allogeneic peripheral blood stem cell (PBSC) products influences transplantation outcomes are conflicting. Using the Center for International Blood and Marrow Transplant Research database, we identified 2736 adult patients who underwent first allogeneic PBSC transplantation for acute leukemia or myelodysplastic syndrome between 2008 and 2014 using an HLA-matched sibling donor (MSD) or an 8/8-matched unrelated donor (MUD). We excluded ex vivo and in vivo T cell-depleted transplantations. Correlative analysis was performed between CD3+ T cell dose and the risk of graft-versus-host-disease (GVHD), relapse, nonrelapse mortality (NRM), disease-free survival (DFS), and overall survival (OS). Using maximum likelihood estimation, we identified CD3+ T cell dose cutoff that separated the risk of acute GVHD (aGVHD) grade II-IV in both the MSD and MUD groups. A CD3+ T cell dose cutoff of 14 × 107 cells/kg identified MSD/low CD3+ (n = 223) and MSD/high CD3+ (n = 1214), and a dose of 15 × 107 cells/kg identified MUD/low CD3+ (n = 197) and MUD/high CD3+ (n = 1102). On univariate analysis, the MSD/high CD3+ group had a higher cumulative incidence of day +100 aGVHD grade II-IV compared with the MSD/low CD3+ group (33% versus 25%; P = .009). There were no differences between the 2 groups in engraftment rate, risk of aGVHD grade III-IV or chronic GVHD (cGVHD), NRM, relapse, DFS, or OS. The MUD/high CD3+ group had a higher cumulative incidence of day +100 aGVHD grade II-IV compared with the MUD/low CD3+ group (49% versus 41%; P = .04). There were no differences between the 2 groups in engraftment rate, risk of severe aGVHD or cGVHD, NRM, relapse, DFS, or OS. Multivariate analysis of the MSD and MUD groups failed to show an association between CD3+ T cell dose and the risk of either aGVHD grade II-IV (P = .10 and .07, respectively) or cGVHD (P = .80 and .30, respectively). Subanalysis of CD4+ T cells, CD8+ T cells, and CD4+/CD8+ ratio failed to identify cutoff values predictive of transplantation outcomes; however, using the log-rank test, the sample size was suboptimal for identifying a difference at this cutoff cell dose. In this registry study, the CD3+ T cell dose of PBSC products did not influence the risk of aGVHD or cGVHD or other transplantation outcomes when using an MSD or an 8/8-matched MUD. Subset analyses of CD4+ and CD8+ T cell doses were not possible given our small sample size.

Overall survival of children and adolescents with mature B cell non-Hodgkin lymphoma who had refractory or relapsed disease during or after treatment with FAB/LMB 96: A report from the FAB/LMB 96 study group

We determined the risk factors associated with poor survival in children and adolescents with de novo mature B cell non-Hodgkin lymphoma (B-NHL) who had refractory or relapsed disease during or after the French-American-British mature lymphoma B (FAB/LMB) 96 multi-agent chemotherapy. Among the 1 111 registered on study, 104 patients (9·4%) had refractory disease or disease relapse after first complete remission. Among these 104 patients, 28 (27%) patients had refractory disease and 76 (73%) had relapsed disease. The estimated 1- and 2-year overall survival (OS) (95% confidence interval) was 31·5% (23·3-41·0%) and 22·3% (15·3-31·4%), respectively. Prognostic analysis of OS using a Cox multivariate model showed that factors independently associated with OS included lactate dehydrogenase ≥2 upper normal limit [hazard ratio (HR) = 2·86 (1·57-5·2), P = 0·0006]; time to failure (>6 months) [HR = 0·59 (0·36-0·97), P = 0·038]; and failure in bone marrow [HR = 2·78 (1·65-4·68), P = 0·0001]. New therapeutic strategies are required to significantly reduce refractory disease and disease relapse in patients with newly diagnosed mature B-NHL and, more importantly, there is a critical need to develop novel retrieval approaches in patients with chemotherapy-resistant disease.

Autologous transplantation versus allogeneic transplantation in patients with follicular lymphoma experiencing early treatment failure

BACKGROUND

Early treatment failure (ETF) in follicular lymphoma (FL), defined as relapse or progression within 2 years of frontline chemoimmunotherapy, is a newly recognized marker of poor survival and identifies a high-risk group of patients with an expected 5-year overall survival (OS) rate of approximately 50%. Transplantation is an established option for relapsed FL, but its efficacy in this specific ETF FL population has not been previously evaluated.

METHODS

This study compared autologous hematopoietic stem cell transplantation (auto-HCT) with either matched sibling donor (MSD) or matched unrelated donor (MUD) allogeneic hematopoietic cell transplantation (allo-HCT) as the first transplantation approach for patients with ETF FL (age ≥ 18 years) undergoing auto-HCT or allo-HCT between 2002 and 2014. The primary endpoint was OS. The secondary endpoints were progression-free survival, relapse, and nonrelapse mortality (NRM).

RESULTS

Four hundred forty FL patients had ETF (auto-HCT, 240; MSD hematopoietic stem cell transplantation [HCT], 105; and MUD HCT, 95). With a median follow-up of 69 to 73 months, the adjusted probability of 5-year OS was significantly higher after auto-HCT (70%) or MSD HCT (73%) versus MUD HCT (49%; P = .0008). The 5-year adjusted probability of NRM was significantly lower for auto-HCT (5%) versus MSD (17%) or MUD HCT (33%; P < .0001). The 5-year adjusted probability of disease relapse was lower with MSD (31%) or MUD HCT (23%) versus auto-HCT (58%; P < .0001).

CONCLUSIONS

Patients with high-risk FL, as defined by ETF, undergoing auto-HCT for FL have low NRM and a promising 5-year OS rate (70%). MSD HCT has lower relapse rates than auto-HCT but similar OS. Cancer 2018;124:2541-51. © 2018 American Cancer Society.

Influence of Age on Acute and Chronic GVHD in Children Undergoing HLA-Identical Sibling Bone Marrow Transplantation for Acute Leukemia: Implications for Prophylaxis

Relapse remains the major cause of mortality after hematopoietic cell transplantation (HCT) for pediatric acute leukemia. Previous research has suggested that reducing the intensity of calcineurin inhibitor-based graft-versus-host disease (GVHD) prophylaxis may be an effective strategy for abrogating the risk of relapse in pediatric patients undergoing matched sibling donor (MSD) HCT. We reasoned that the benefits of this strategy could be maximized by selectively applying it to those patients least likely to develop GVHD. We conducted a study of risk factors for GVHD, to risk-stratify patients based on age. Patients age <18 years with leukemia who received myeloablative, T cell-replete MSD bone marrow transplantation and calcineurin inhibitor-based GVHD prophylaxis between 2000 and 2013 and were entered into the Center for International Blood and Marrow Transplant Research registry were included. The cumulative incidence of grade II-IV acute GVHD (aGVHD) was 19%, that of grade II-IV aGVHD 7%, and that of chronic GVHD (cGVHD) was 16%. Compared with age 13 to 18 years, age 2 to 12 years was associated with a lower risk of grade II-IV aGVHD (hazard ratio [HR], .42; 95% confidence interval [CI], .26 to .70; P = .0008), grade II-IV aGVHD (HR, .24; 95% CI, .10 to .56; P = .001), and cGVHD (HR, .32; 95% CI, .19 to .54; P < .001). Compared with 2000-2004, the risk of grade II-IV aGVHD was lower in children undergoing transplantation in 2005-2008 (HR, .36; 95% CI, .20 to .65; P = .0007) and in 2009-2013 (HR, .24; 95% CI. .11 to .53; P = .0004). Similarly, the risk of grade III-IV aGVHD was lower in children undergoing transplantation in 2005-2008 (HR, .23; 95% CI, .08 to .65; P = .0056) and 2009-2013 (HR, .16; 95% CI, .04 to .67; P = .0126) compared with those doing so in 2000-2004. We conclude that aGVHD rates have decreased significantly over time, and that children age 2 to 12 years are at very low risk for aGVHD and cGVHD. These results should be validated in an independent analysis, because these patients with high-risk malignancies may be good candidates for trials of reduced GVHD prophylaxis.

Abstract 2657: PD-L1 blockade enhances T cell cytotoxicity against primary mediastinal B cell lymphoma

Background:

Primary Mediastinal B cell Lymphoma (PMBL) represents 2-4% of Non-Hodgkin Lymphomas (NHL) in adolescents and young adults (AYA) (Gerrard/Cairo et al., Blood, 2013). Disease progression, relapse and long-term toxicity remain a concern for patients treated on current chemo-immunotherapy and mediastinal radiotherapy. Alternative therapeutic regimens are urgently needed, especially in patients without an early response to therapy. Programmed Death 1 (PD-1) is a negative co-stimulatory receptor critical for suppression of T-cell activation, with binding of PD-1 and Programmed Death Ligand 1 (PD-L1) resulting in T cell exhaustion (Postow/Wolchok et al., J Clin Oncol, 2015). Gain in 9p associated with amplification of PD-L1 has been reported in up to 60% of PMBL specimens, leading to overexpression of PD-L1 and potential immune cell evasion of PMBL (Rosenwald/Staudt et al., J Exp Med, 2003; Twa/Steidl et al., Blood, 2014). Blockade of PD-1/PD-L1 interaction, therefore, constitute a potentially promising alternative for treatment of resistant PMBL.

Objective:

In the current study, we sought to investigate whether PD-L1 blockade enhances T cell responses in PD-L1 expressing PMBL.

Methods:

PD-L1 expression on Karpas 1106p PMBL treated with or without IFN γ was investigated by western blotting and flow cytometry analyses. T cells were isolated from human PBMC followed by activation and expansion using anti-CD2, anti-CD3 and anti-CD28 Biotinylated MACSiBead particles. T cell activation was confirmed by CD25 and CD69 expression using flow cytometry. Activated T cells were incubated with or without anti-PD-L1 (Clone 6E11, Genentech) at a dose of 10 ug/ml together with Karpas 1106p cells treated with or without IFN γ. Cell proliferation was assessed with MTS assays after incubation for 24 hours.

Results:

We demonstrated that Karpas 1106p cells express a low level of PD-L1. However, following IFN γ treatment (48 hours) there was a significant increase in PD-L1 expression. Anti-PD-L1 had no significant effect on T cell mediated inhibition of cell proliferation in Karpas 1106p cells with low PD-L1 expression. However, anti-PD-L1 and T cell treatment significantly inhibited cell proliferation in IFN γ treated Karpas 1106p cells when compared to T cell treatment alone (32±18% vs. 3±3% at E:T=5:1, p=0.048).

Conclusion:

PD-L1 blockade enhances T cell cytotoxicity against PMBL, which is dependent on PD-L1 expression level on PMBL cells. Future in-vivo NSG xenograft studies are ongoing.

Citation Format: Tishi Shah, Wen Luo, Aradhana Awasthi, Janet Ayello, Jessica Hochberg, Mitchell Cairo. PD-L1 blockade enhances T cell cytotoxicity against primary mediastinal B cell lymphoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2657. doi:10.1158/1538-7445.AM2017-2657

Improved survival after acute graft-versus-host disease diagnosis in the modern era

A cute graft-versus-host disease remains a major threat to a successful outcome after allogeneic hematopoietic cell transplantation. While improvements in treatment and supportive care have occurred, it is unknown whether these advances have resulted in improved outcome specifically among those diagnosed with acute graft-versus-host disease. We examined outcome following diagnosis of grade II-IV acute graft-versus-host disease according to time period, and explored effects according to original graft-versus-host disease prophylaxis regimen and maximum overall grade of acute graft-versus-host disease. Between 1999 and 2012, 2,905 patients with acute myeloid leukemia (56%), acute lymphoblastic leukemia (30%) or myelodysplastic syndromes (14%) received a sibling (24%) or unrelated donor (76%) blood (66%) or marrow (34%) transplant and developed grade II-IV acute graft-versus-host disease (n=497 for 1999–2001, n=962 for 2002–2005, n=1,446 for 2006–2010). The median (range) follow-up was 144 (4–174), 97 (4–147) and 60 (8–99) months for 1999–2001, 2002–2005, and 2006–2010, respectively. Among the cohort with grade II-IV acute graft-versus-host disease, there was a decrease in the proportion of grade III-IV disease over time with 56%, 47%, and 37% for 1999–2001, 2002–2005, and 2006–2012, respectively (P<0.001). Considering the total study population, univariate analysis demonstrated significant improvements in overall survival and treatment-related mortality over time, and deaths from organ failure and infection declined. On multivariate analysis, significant improvements in overall survival (P=0.003) and treatment-related mortality (P=0.008) were only noted among those originally treated with tacrolimus-based graft-versus-host disease prophylaxis, and these effects were most apparent among those with overall grade II acute graft-versus-host disease. In conclusion, survival has improved over time for tacrolimus-treated transplant recipients with acute graft-versus-host disease.

The Society for Immunotherapy of Cancer consensus statement on immunotherapy for the treatment of hematologic malignancies: multiple myeloma, lymphoma, and acute leukemia

Increasing knowledge concerning the biology of hematologic malignancies as well as the role of the immune system in the control of these diseases has led to the development and approval of immunotherapies that are resulting in impressive clinical responses. Therefore, the Society for Immunotherapy of Cancer (SITC) convened a hematologic malignancy Cancer Immunotherapy Guidelines panel consisting of physicians, nurses, patient advocates, and patients to develop consensus recommendations for the clinical application of immunotherapy for patients with multiple myeloma, lymphoma, and acute leukemia. These recommendations were developed following the previously established process based on the Institute of Medicine's clinical practice guidelines. In doing so, a systematic literature search was performed for high-impact studies from 2004 to 2014 and was supplemented with further literature as identified by the panel. The consensus panel met in December of 2014 with the goal to generate consensus recommendations for the clinical use of immunotherapy in patients with hematologic malignancies. During this meeting, consensus panel voting along with discussion were used to rate and review the strength of the supporting evidence from the literature search. These consensus recommendations focus on issues related to patient selection, toxicity management, clinical endpoints, and the sequencing or combination of therapies. Overall, immunotherapy is rapidly emerging as an effective therapeutic strategy for the management of hematologic malignances. Evidence-based consensus recommendations for its clinical application are provided and will be updated as the field evolves.

Allogeneic transplantation provides durable remission in a subset of DLBCL patients relapsing after autologous transplantation

For diffuse large B-cell lymphoma (DLBCL) patients progressing after autologous haematopoietic cell transplantation (autoHCT), allogeneic HCT (alloHCT) is often considered, although limited information is available to guide patient selection. Using the Center for International Blood and Marrow Transplant Research (CIBMTR) database, we identified 503 patients who underwent alloHCT after disease progression/relapse following a prior autoHCT. The 3-year probabilities of non-relapse mortality, progression/relapse, progression-free survival (PFS) and overall survival (OS) were 30, 38, 31 and 37% respectively. Factors associated with inferior PFS on multivariate analysis included Karnofsky performance status (KPS) <80, chemoresistance, autoHCT to alloHCT interval <1-year and myeloablative conditioning. Factors associated with worse OS on multivariate analysis included KPS<80, chemoresistance and myeloablative conditioning. Three adverse prognostic factors were used to construct a prognostic model for PFS, including KPS<80 (4 points), autoHCT to alloHCT interval <1-year (2 points) and chemoresistant disease at alloHCT (5 points). This CIBMTR prognostic model classified patients into four groups: low-risk (0 points), intermediate-risk (2-5 points), high-risk (6-9 points) or very high-risk (11 points), predicting 3-year PFS of 40, 32, 11 and 6%, respectively, with 3-year OS probabilities of 43, 39, 19 and 11% respectively. In conclusion, the CIBMTR prognostic model identifies a subgroup of DLBCL patients experiencing long-term survival with alloHCT after a failed prior autoHCT.

Abstract 3096: Obinutuzumab (GA101) significantly induces antiproliferative effects and programmed cell death, and significantly downregulates cell signaling pathways in primary mediastinal B-cell lymphoma (PMBL): Obinutuzumab may be a future potential targeted agent for treatment of PMBL

BACKGROUND: Primary Mediastinal large B-cell lymphoma (PMBL) is a rare form of non-Hodgkin Lymphoma (NHL) representing 2% of mature B-cell NHL in patients ≤ 18 years of age (Lones/Cairo et al., JCO, 2000). PMBL is classified as a distinct mature B-Cell lymphoma and is considered midway in the biologic spectrum between Diffuse Large B-Cell Lymphoma (DLBCL) and classical HL (Abramson et al., Blood, 2005). We have recently reported a significant decrease in EFS among children and adolescent PMBL patients compared with other stage III non-PMBL pediatric DLBCL patients following FAB/LMB 96 therapy, suggesting that children and adolescent PMBL may be an inherently different B-NHL (Gerrard/Cairo et al., Blood, 2013). Since 98% of PMBL express CD20, targeting the CD20 receptor with a CD20 antibody is of high clinical interest. Obinutuzumab (GA101) is a novel, anti-CD20 targeted monoclonal antibody recognizing a unique CD20 type II epitope and has been demonstrated to have efficacy in reducing tumor size and improving survival in other B-NHL xenograft models (Mössner et al., Blood, 2010).

OBJECTIVES: We hypothesize that obinutuzumab may be a future potential targeted agent for the treatment of PMBL, and therefore, we investigated the effect of obinutuzumab on cell proliferation, programmed cell death, and cell signaling pathways in PMBL.

METHODS: CD20+ PMBL, Karpas-1106P cells (Karpas) were obtained from the DSMZ, Germany and obinutuzumab was generously provided by C. Klein, Roche. Cell proliferation and apoptotic rate were assessed using MTS and FACS analysis, respectively. Statistical significance was determined by one-tailed Student's t-test.

RESULTS: There was a significant decrease of cell proliferation in obinutuzumab-treated Karpas vs PBS-treated Karpas (1.000 ± 0.000) at 48 hours with 1ug/ml (0.723 ± 0.005, p=0.0007), 10ug/ml (0.688 ± 0.025, p=0.0033), and 20ug/ml (0.627 ± 0.042, p=0.0092) obinutuzumab treatment. There was a significant increase in cell death in Karpas following 10ug/ml obinutuzumab treatment (37.790 ± 10.096, p=0.018) as compared to IgG isotope (1.040 ± 0.834, p=0.340) and PBS control (1.190 ± 0.762) at 48 hours by FACS analysis. We also observed significant decreases in the phosphorylation of Stat6 (0.730 ± 0.005, p=0.0001), Akt (0.691 ± 0.002, p&lt;0.0001), IkBa (0.706 ± 0.006, p=0.0002) and Erk (0.578 ± 0.001, p&lt;0.0001) in 10ug/ml obinutuzumab-treated Karpas as compared to control (1.000 ± 0.000).

CONCLUSIONS: Obinutuzumab significantly induced antiproliferative effects and cell death in PMBL and may be a future potential targeted agent for the treatment of PMBL. The effect(s) of obinutuzumab will be evaluated in vivo in a NOD/SCID PMBL xenograft mouse model.

Citation Format: Changhong Yin, Timmy O'Connell, Janet Ayello, Carmella van de Ven, Sanghoon Lee, Mitchell Cairo. Obinutuzumab (GA101) significantly induces antiproliferative effects and programmed cell death, and significantly downregulates cell signaling pathways in primary mediastinal B-cell lymphoma (PMBL): Obinutuzumab may be a future potential targeted agent for treatment of PMBL. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3096. doi:10.1158/1538-7445.AM2014-3096

Outcome of transplantation for acute lymphoblastic leukemia in children with Down syndrome

We report on 27 patients with Down syndrome (DS) and acute lymphoblastic leukemia (ALL) who received allogeneic hematopoietic cell transplantation (HCT) between 2000 and 2009. Seventy-eight percent of patients received myeloablative conditioning and 52% underwent transplantation in second remission. Disease-free survival (DFS) was 24% at a median of 3 years. Post-transplant leukemic relapse was more frequent than expected for children with DS-ALL (54%) than for non-DS ALL. These data suggest leukemic relapse rather than transplant toxicity is the most important cause of treatment failure. Advancements in leukemia control are especially needed for improvement in HCT outcomes for DS-ALL.

Outcome of transplantation for acute myelogenous leukemia in children with Down syndrome

Data on outcomes of allogeneic transplantation in children with Down syndrome and acute myelogenous leukemia (DS-AML) are scarce and conflicting. Early reports stress treatment-related mortality as the main barrier; a recent case series points to posttransplantation relapse. We reviewed outcome data for 28 patients with DS-AML reported to the Center for International Blood and Marrow Transplant Research between 2000 and 2009 and performed a first matched-pair analysis of 21 patients with DS-AML and 80 non-DS AML controls. The median age at transplantation for DS-AML was 3 years, and almost half of the cohort was in second remission. The 3-year probability of overall survival was only 19%. In multivariate analysis, adjusting for interval from diagnosis to transplantation, risks of relapse (hazard ratio [HR], 2.84; P < .001; 62% versus 37%) and transplant-related mortality (HR, 2.52; P = .04; 24% versus 15%) were significantly higher for DS-AML compared to non-DS AML. Overall mortality risk (HR, 2.86; P < .001; 21% versus 52%) was significantly higher for DS-AML. Both transplant-related mortality and relapse contribute to higher mortality. Excess mortality in DS-AML patients can only effectively be addressed through an international multicenter effort to pilot strategies aimed at lowering both transplant-related mortality and relapse risks.

Blood pressure control in Italian essential hypertensives treated by general practitioners

BACKGROUND

Adequate control of blood pressure (BP) is limited worldwide. This has serious consequences for public health because in hypertensive patients, uncontrolled BP is associated with a higher incidence of cardiovascular events, particularly stroke. The aim of this study was to investigate BP control in a cohort of treated patients with diagnosed hypertension, who were under general practitioner care in Italy.

METHODS

Data were collected by 2,643 physicians on 8,572 individual Italian patients. Office BP was measured 5 min after seating each patient and then 3-5 min later. For each patient, data such as medical history of patients, physical examination data, antihypertensive drug usage, and self-BP measurement frequency were obtained.

RESULTS

Male prevalence was 48.4%, and mean age was 64.3 ± 10.5 years. Based on the second measurement, BP control (<140/90 mm Hg) was observed in 33.5% of all patients (34.2% in men and 33.4% in women). BP control was much lower for systolic BP than for diastolic BP (35.9 vs. 61.3%, P < 0.0001); moreover, BP control was much more common in patients who were engaged in self-BP measurement (61.2 vs. 38.8%, P < 0.0001). A stricter BP control recommended by the guidelines of the European Society of Hypertension (ESH) and European Society of Cardiology (ESC) (<130/80 mm Hg) was observed in only 5.5% of diabetic patients.

CONCLUSIONS

In treated Italian hypertensives effective BP control remains uncommon largely due to the failure to appropriately reduce the systolic BP. The stricter values recommended by the ESH/ESC guidelines for diabetic patients are achieved only by a small fraction of hypertensive diabetic population.

Transplantation for autoimmune diseases in north and South America: a report of the Center for International Blood and Marrow Transplant Research

Hematopoietic cell transplantation (HCT) is an emerging therapy for patients with severe autoimmune diseases (AID). We report data on 368 patients with AID who underwent HCT in 64 North and South American transplantation centers reported to the Center for International Blood and Marrow Transplant Research between 1996 and 2009. Most of the HCTs involved autologous grafts (n = 339); allogeneic HCT (n = 29) was done mostly in children. The most common indications for HCT were multiple sclerosis, systemic sclerosis, and systemic lupus erythematosus. The median age at transplantation was 38 years for autologous HCT and 25 years for allogeneic HCT. The corresponding times from diagnosis to HCT were 35 months and 24 months. Three-year overall survival after autologous HCT was 86% (95% confidence interval [CI], 81%-91%). Median follow-up of survivors was 31 months (range, 1-144 months). The most common causes of death were AID progression, infections, and organ failure. On multivariate analysis, the risk of death was higher in patients at centers that performed fewer than 5 autologous HCTs (relative risk, 3.5; 95% CI, 1.1-11.1; P = .03) and those that performed 5 to 15 autologous HCTs for AID during the study period (relative risk, 4.2; 95% CI, 1.5-11.7; P = .006) compared with patients at centers that performed more than 15 autologous HCTs for AID during the study period. AID is an emerging indication for HCT in the region. Collaboration of hematologists and other disease specialists with an outcomes database is important to promote optimal patient selection, analysis of the impact of prognostic variables and long-term outcomes, and development of clinical trials.

Comparison of reduced-intensity hematopoietic cell transplantation with chemotherapy in patients age 60-70 years with acute myelogenous leukemia in first remission

We compared the outcomes of patients age 60-70 years with acute myelogenous leukemia receiving reduced-intensity allogeneic hematopoietic cell transplantation (HCT) in first remission (CR1) reported to the Center for International Blood and Marrow Research (n = 94) with the outcomes in patients treated with induction and postremission chemotherapy on Cancer and Leukemia Group B protocols (n = 96). All patients included had been in CR1 for at least 4 months. The HCT recipients were slightly younger than the chemotherapy patients (median age, 63 years vs 65 years; P < .001), but there were no significant between-group differences in the proportion with therapy-related leukemia or in different cytogenetic risk groups. Time from diagnosis to CR1 was longer for the HCT recipients (median, 44 days vs 38 days; P = .031). Allogeneic HCT was associated with significantly lower risk of relapse (32% vs 81% at 3 years; P < .001), higher nonrelapse mortality (36% vs 4% at 3 years; P < .001), and longer leukemia-free survival (32% vs 15% at 3 years; P = .001). Although overall survival was longer for HCT recipients, the difference was not statistically significant (37% vs 25% at 3 years; P = .08). Our findings suggest that reduced-intensity conditioning allogeneic HCT in patients age 60-70 with acute myelogenous leukemia in CR1 reduces relapse and improves leukemia-free survival. Strategies that reduce nonrelapse mortality may yield significant improvements in overall survival.

Hematopoietic stem-cell transplantation for acute leukemia in relapse or primary induction failure

PURPOSE

Patients with acute leukemia refractory to induction or reinduction chemotherapy have poor prognoses if they do not undergo hematopoietic stem-cell transplantation (HSCT). However, HSCT when a patient is not in complete remission (CR) is of uncertain benefit. We hypothesized that pretransplantation variables may define subgroups that have a better prognosis.

PATIENTS AND METHODS

Overall, 2,255 patients who underwent transplantation for acute leukemia in relapse or with primary induction failure after myeloablative conditioning regimen between 1995 and 2004 were reported to the Center for International Blood and Marrow Transplant Research. The median follow-up of survivors was 61 months. We performed multivariate analysis of pretransplantation variables and developed a predictive scoring system for survival.

RESULTS

The 3-year overall survival (OS) rates were 19% for acute myeloid leukemia (AML) and 16% for acute lymphoblastic leukemia (ALL). For AML, five adverse pretransplantation variables significantly influenced survival: first CR duration less than 6 months, circulating blasts, donor other than HLA-identical sibling, Karnofsky or Lansky score less than 90, and poor-risk cytogenetics. For ALL, survival was worse with the following: first refractory or second or greater relapse, > or = 25% marrow blasts, cytomegalovirus-seropositive donor, and age of 10 years or older. Patients with AML who had a predictive score of 0 had 42% OS at 3 years, whereas OS was 6% for a score > or = 3. Patients with ALL who had a score of 0 or 1 had 46% 3-year OS but only 10% OS rate for a score > or = 3.

CONCLUSION

Pretransplantation variables delineate subgroups with different outcomes. HSCT during relapse can achieve long-term survival in selected patients with acute leukemia.

Advancement of pediatric blood and marrow transplantation research in North America: priorities of the Pediatric Blood and Marrow Transplant Consortium

Advances in pediatric bone marrow transplantation (BMT) are slowed by the small number of patients with a given disease who undergo transplantation, a lack of sufficient infrastructure to run early-phase oncology protocols and studies of rare nonmalignant disorders, and challenges associated with funding multi-institutional trials. Leadership of the Pediatric Blood and Marrow Transplant Consortium (PBMTC), a large pediatric BMT clinical trials network representing 77 active and 45 affiliated centers worldwide, met in April 2009 to develop strategic plans to address these issues. Key barriers, including infrastructure development and funding, along with scientific initiatives in malignant and nonmalignant disorders, cellular therapeutics, graft-versus-host disease, and supportive care were discussed. The PBMTC's agenda for approaching these issues will result in infrastructure and trials specific to pediatrics that will run through the PBMTC or its partners, the Blood and Marrow Transplant Clinical Trials Network and the Children's Oncology Group.

A BRCA1-Like, 25-Gene Assay Predicts for Anthracycline-Chemosensitivity in Sporadic Triple-Negative Breast Cancer

Background Studies have shown higher chemosensitivity to anthracyclines in BRCA1-associated breast cancer (BABC) when compared to sporadic triple-negative breast cancers (TNBC), possibly due to differences in DNA repair function. We hypothesized that a subset of TNBC with acquired BRCA1 deficiency and defective DNA repair function will benefit most from DNA-damaging agents, such as anthracyclines. Methods We applied a previously published BRCA1 gene expression signature that differentiates BABC from sporadic TNBC to three datasets of sporadic TNBC from Baylor College of Medicine (BCM, n=68), GSE2034 (n=49), and the Netherlands Cancer Institute (NKI2, n=40). The signature separated the sporadic TNBC samples into those with a gene expression profile similar to BABC, or BRCA1-like, versus those with an expression pattern similar to sporadic TNBC, nonBRCA1-like. A list of 92 genes was obtained from the overlap of the most differentially expressed genes between the BRCA1-like samples and nonBRCA1-like samples in each of the three datasets. We then confirmed a subset of the 25 most differentially expressed genes by quantitative RTPCR. We validated the predictive value of this BRCA1-based, 25-gene assay in anthracycline response in three neoadjuvant studies of fluorouracil, epirubicin, and cyclophosphamide (FEC 6 cycles, n=53), doxorubicin and cyclophosphamide (AC 4 cycles, n=12), and T-FAC (paclitaxel-FAC, n=16). Results We determined gene expression of the 92 candidate genes by RT-PCR on 30 available samples of the BCM database. 25 genes were found to have the highest correlation between the microarray and RTQPCR gene expression. Gene expression profile using these 25-gene assay was obtained for three databases which included neoadjuvant anthracycline response data. The 25-gene assay predicted for anthracycline response in sporadic triple-negative breast cancers. In a neoadjuvant FEC study, this assay predicted for pathologic complete response (pCR) in 14/25 patients with BRCA1-like pattern, vs. 7/25 with sporadic-like pattern, p&lt;0.05. In the AC study, 6/9 patients in the BRCA1-like group achieved pCR, vs. 0/3 in nonBRCA1-like group, p&lt;0.05. Finally, in the T-FAC study, 5/7 patients in the BRCA1-like group achieved pCR vs. 3/9 patients in the nonBRCA1-like group, p=0.15. Analysis of the microarray data of triple negative breast cancer revealed higher PARP1 expression levels in the BRCA1-like group when compared to nonBRCA1-like group. Conclusion We present a promising BRCA1-based 25-gene assay that can be used on formalin-fixed paraffin-embedded tissue that may guide therapy in triple- negative breast cancer. The assay differentiates TNBC that are very sensitive to anthracyclines, and it should now be tested and validated prospectively in clinical trials with anthracyclines, other DNA-damaging agents, and PARP1 inhibitors.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 110.

Phase I and pharmacokinetic (PK) study of lenalidomide (LEN) in pediatric patients with relapsed/refractory solid tumors or myelodysplastic syndrome (MDS): A Children's Oncology Group Phase I Consortium study

10023

Background: LEN, which has immunomodulatory, antiangiogenic, and antiproliferative effects, is indicated for the treatment of adults with MDS and multiple myeloma. We report the final results of a phase 1 and PK study of LEN in children with recurrent or refractory solid tumors (ST) or MDS. Methods: LEN was administered by mouth once daily for 21 of 28 days. Cohorts of 3 to 12 children with ST were enrolled at 15, 25, 40, 55 and 70 mg/m2/d dose levels. Children with MDS received a fixed dose of 5 mg/m2/d. PK and correlative biology studies were performed in cycle 1. Results: 49 patients (23 female), median age 16 years (range, 1–21) were enrolled and received a median of 1 cycle (range 1–11). 39/46 ST patients and 3/3 MDS patients were fully evaluable for toxicity. 0/3 patients with MDS had DLT. At 15 mg/m2/d, 1/6 ST patients developed DLT (Gr 3 hypercalcemia). At 25 mg/m2/d 1 patient had a cerebrovascular ischemic event of uncertain relationship to LEN; future subjects were screened for thromboembolic risk factors prior to enrollment. At 40 mg/m2/d 3/12 patients developed DLTs (Gr 3 hypophosphatemia/hypokalemia; Gr 4 neutropenia delaying the start of the next cycle for > 7 days; Gr 3 somnolence); at 55 mg/m2/d 1/6 patients developed DLT (Gr 3 urticaria). At 70 mg/m2/d 0/6 patients had DLT. No further dose escalation was attempted. No objective responses were observed. LEN enhanced IL-2 and IL-15 concentrations; NK expansion and activation; and NK and LAK cytotoxicity (Ayello, ASH, 2008). The median apparent LEN clearance and half-life were 135 ± 45 ml/min/m2 and 2.3 ± 1.1 hr. Conclusions: LEN is well tolerated at doses up to 70 mg/m2/d x 21d of 28 days in children with recurrent or refractory ST. Enhancement of immune function is significant. PK parameters in children are similar to those in adults.

No significant financial relationships to disclose.

Prior rituximab correlates with less acute graft-versus-host disease and better survival in B-cell lymphoma patients who received allogeneic peripheral blood stem cell transplantation

Prior therapy with rituximab might attenuate disparate histocompatibility antigen presentation by B cells, thus decreased the risk of acute graft-versus-host disease (GVHD) and improved survival. We tested this hypothesis by comparing the outcomes of 435 B-cell lymphoma patients who received allogeneic transplantation from 1999 to 2004 in the Center for International Blood and Marrow Transplant Research database: 179 subjects who received rituximab within 6 months prior to transplantation (RTX cohort) and 256 subjects who did not receive RTX within 6 months prior to transplantation (No-RTX cohort). The RTX cohort had a significantly lower incidence of treatment-related mortality (TRM) [relative risk (RR) = 0.68; 95% confidence interval (CI), 0.47-1.0; P = 0.05], lower acute grade II-IV (RR = 0.72; 95% CI, 0.53-0.97; P = 0.03) and III-IV GVHD (RR = 0.55; 95% CI, 0.34-0.91; P = 0.02). There was no difference in the risk of chronic GVHD, disease progression or relapse. Progression-free survival (PFS) (RR = 0.68; 95% CI 0.50-0.92; P = 0.01) and overall survival (OS) (RR = 0.63; 95% CI, 0.46-0.86; P = 0.004) were significantly better in the RTX cohort. Prior RTX therapy correlated with less acute GVHD, similar chronic GVHD, less TRM, better PFS and OS.

A study of rituximab and ifosfamide, carboplatin, and etoposide chemotherapy in children with recurrent/refractory B-cell (CD20+) non-Hodgkin lymphoma and mature B-cell acute lymphoblastic leukemia: a report from the Children's Oncology Group

BACKGROUND

To estimate the response rate and therapy related toxicities of the anti-CD20 monoclonal antibody rituximab when combined with chemotherapy including ifosfamide, carboplatin, and etoposide (ICE) in patients with relapsed and refractory B-cell non-Hodgkin lymphoma and mature B-cell acute lymphoblastic leukemia (B-ALL).

METHODS

Patients received rituximab and ICE for 1-3 cycles, depending upon response. Rituximab (375 mg/m(2)) was given on day 1 and 3 of each cycle (day 1 only for cycle 3), with ifosfamide (3,000 mg/m(2)) and etoposide (100 mg/m(2)) given on days 3, 4, and 5 and carboplatin (635 mg/m(2)) given on day 3 only.

RESULTS

Twenty-one patients were enrolled, of whom 20 were eligible and evaluable. Although hematologic toxicities were common, only one patient was removed from study due to prolonged myelosuppression. Toxicities related to infusions of rituximab were frequent but manageable. Of the six eligible patients with diffuse large B-cell lymphoma, three achieved complete remission (CR), one had stable disease (SD), and two had progressive disease (PD). Of the 14 eligible patients with Burkitt lymphoma and B-ALL, there were four complete responses (CR), five partial responses (PR), one SD, and four with PD. Thus, the CR/PR rate for the entire group was 12/20 (60%). Following completion of protocol therapy six patients were able to proceed to consolidation with high-dose therapy and stem cell rescue.

CONCLUSIONS

The combination of rituximab and ICE chemotherapy was associated with an encouraging objective response (OR) rate and an acceptable toxicity profile.

Decreased TGFβ signaling and increased COX2 expression in high risk women with increased mammographic breast density

Abstract #1107

Background&#x2028; High mammographic density is associated with up to a 6-fold increased risk of breast cancer. Pathways responsible for this increased density are unknown. We hypothesize that specific molecular pathways exist that are associated with increased mammographic density and breast cancer risk, and may therefore be used to identify potential targets for chemoprevention.&#x2028; Methods&#x2028; Histologically confirmed normal breast tissue was collected from women undergoing breast surgery who had available demographic data and mammograms for review. Breast parenchymal density was classified according to the American College of Radiology's Breast Imaging – Reporting and Data System reporting system. Quantitative classification of mammographic parenchyma was performed using thresholding method and percent density. Women with low (less than 50%) versus high (greater than 50%) breast density were compared. Double-stranded cDNA was synthesized from the normal breast tissue using an oligo-dT primer containing a T7 RNA polymerase promoter, followed by in vitro transcription with biotinylated ribonucleotides. The labeled cRNA was hybridized to Affymetrix HG U133Plus2 chips which comprise ∼28,600 genes to determine gene expression patterns. Immunohistochemical analysis (IHC) of estrogen receptor, progesterone receptor, proliferation (Ki67) and COX2 expression was performed.&#x2028; Results&#x2028; Sixty-two women were identified, 26 (42%) had high, and 36 (58%) had low mammographic density. Neither age, menopausal nor hormone receptor status influenced the gene expression pattern. Seventy-three genes had differential expression between normal breast tissue with high and low mammographic density (p&lt;0.001, fold change&gt;1.5) and had a low false discovery rate (&lt;10%). Of these 73 differentially expressed genes, network and canonical pathway analysis demonstrate decreased TGFβ signaling (TGFBR2, SOS, SMAD3 and CD44 expression) in dense breast relative to non-dense breast. By IHC, Ki67 (stroma) and COX2 expression were significantly higher in dense breasts (p&lt;0.05) on univariate analysis, and only COX2 expression in the stroma was statistically significant at (p&lt;0.01) on multivariate analysis.&#x2028; Conclusion&#x2028; TGFβ ligands are currently the only growth factors known to prevent mammary epithelial cell proliferation. TGFβ has been reported to influence COX-2 expression, and these molecules are highly differentially expressed in individuals at high risk of developing breast cancer. These results suggest that COX2 inhibition should be further investigated for breast cancer prevention despite possible increase in cardiovascular risk.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1107.

Nontuberculous mycobacterial infections in pediatric hematopoietic stem cell transplant recipients: case report and review of the literature

Nontuberculous mycobacterial (NTM) infections are rarely diagnosed in hematopoietic stem cell transplant (HSCT) recipients. We describe a case of disseminated Mycobacterium avium complex with gastrointestinal tract involvement in a HSCT recipient. We reviewed NTM infections among pediatric HSCT patients at our institution from 2000-2004 and identified 2 additional cases. Fourteen published case reports of NTM disease in children are reviewed.