HIV Status Does Not Affect the Outcome of Autologous Stem Cell Transplantation (ASCT) for Non-Hodgkin Lymphoma (NHL)

Randomized trials comparing autologous stem cell transplant (ASCT) to conventional chemotherapy have demonstrated superior survival among HIV-negative ASCT patients with relapsed non-Hodgkin lymphoma (NHL). Recent trials explored the feasibility of ASCT in the HIV setting. Although these studies have shown that ASCT in HIV-positive NHL patients (HIVpos-NHL) is well tolerated, the impact of HIV infection on long-term transplant outcome is not well characterized. Ongoing comparison of long-term survival following ASCT in HIVpos-NHL patients and HIVneg-NHL patients will allow investigators to explore whether there should be inclusion of HIVpos-NHL patients in ASCT trials. To study long-term outcome we conducted a single-institution matched case-controlled study in HIVpos-NHL patients (cases) and HIVneg-NHL patients (controls). Twenty-nine patients with HIVpos-NHL were matched with HIVneg-NHL controls on sex, time to ASCT, year of transplant, histology, age, disease status, number prior regimens, and conditioning regimen. Nonrelapse mortality (NRM) was similar: 11% (95% confidence interval [CI]: 4%-28%) in HIVpos-NHL patients and 4% (95% CI: 1%-25%) in HIVneg-NHL controls (P = .18). Two-year disease-free survival (DFS) for the HIVpos-NHL patients was 76% (95% CI: 62%-85%) and 56% (95% CI: 45%-66%) for the HIVneg-NHL controls (P = .33). Overall survival was also similar; the 2-year point estimates were 75% (95% CI: 61%-85%) and 75% (95% CI: 60%-85%), respectively (P = .93), despite inclusion of more poor risk HIVpos-NHL patients. These results provide further evidence that HIV status does not affect the long-term outcome of ASCT for NHL, and therefore HIV status alone should no longer exclude these patients from transplant clinical trials

Matched-Cohort Analysis of Autologous Hematopoietic Cell Transplantation with Radioimmunotherapy versus Total Body Irradiation–Based Conditioning for Poor-Risk Diffuse Large Cell Lymphoma

We conducted a matched-cohort analysis of autologous transplant conditioning regimens for diffuse large cell lymphoma in 92 patients treated with either radioimmunotherapy (RIT) or total body irradiation (TBI)–based conditioning regimens. The RIT regimen consisted of 0.4 mCi/kg of 90Y-ibritumomab tiuxetan plus BEAM (BCNU, etoposide, cytarabine, melphalan). The TBI-based regimen combined fractionated TBI at 1200 cGy, with etoposide and cyclophosphamide. Five factors were matched between 46 patient pairs: age at transplant ±5 years, disease status at salvage, number of prior regimens, year of diagnosis ±5 years, and year of transplantation ±5 years. Patients in the TBI group had higher rates of cardiac toxicity and mucositis, whereas Z-BEAM patients had a higher incidence of pulmonary toxicity. Overall survival at 4 years was 81.0% for the Z-BEAM and 52.7% for the TBI group (P = .01). The 4-year cumulative incidence of relapse/progression was 40.4% and 42.1% for Z-BEAM and TBI, respectively (P = .63). Nonrelapse mortality was superior in the Z-BEAM group: 0% compared with 15.8% for TBI at 4 years (P < .01). Our data demonstrate that RIT-based conditioning had a similar relapse incidence to TBI, with lower toxicity, resulting in improved overall survival, particularly in patients with ≥2 prior regimens

High-Dose Therapy and Autologous Hematopoietic Cell Transplantation in Peripheral T Cell Lymphoma (PTCL): Analysis of Prognostic Factors

Patients with peripheral T cell lymphoma (PTCL) have a poor prognosis with current treatment approaches. We examined the outcomes of high-dose therapy (HDT) and autologous hematopoietic cell transplant (AHCT) on the treatment of PTCL and the impact of patient/disease features on long-term outcome. Sixty-seven patients with PTCL–not otherwise specified (n = 30), anaplastic large cell lymphoma (n = 30), and angioimmunoblastic T cell lymphoma (n = 7) underwent HDT/AHCT at the City of Hope. The median age was 48 years (range: 5-78). Twelve were transplanted in first complete remission (1CR)/partial remission (PR) and 55 with relapsed or induction failure disease (RL/IF). With a median follow-up for surviving patients of 65.8 months (range: 24.5-216.0) the 5-year overall survival (OS) and progression-free survival (PFS) were 54% and 40%, respectively. The 5-year PFS was 75% for 1CR/PR compared to 32% for RL/IF patients (P = .01). When the Prognostic Index for PTCL unspecified (PIT) was applied at the time of transplant, patients in the PIT 3-4 group had 5-year PFS of only 8%. These results show that HDT/AHCT can improve long-term disease control in relapsed/refractory PTCL and that HDT/AHCT should ideally be applied either during 1CR/PR, or as part of upfront treatment. More effective and novel therapies are needed for patients with high-risk disease (PIT 3-4 factors) and allogeneic HCT should be explored in these patients

Increased Programmed Death-1 Molecule Expression in Cytomegalovirus Disease and Acute Graft-versus-Host Disease after Allogeneic Hematopoietic Cell Transplantation

To study the role of the programmed death-1 molecule (PD-1) in cytomegalovirus (CMV) infection and disease after allogeneic hematopoietic cell transplantation (HCT), 206 subjects were followed prospectively for immune response to CMV and assigned to 3 groups based on CMV outcome. The subjects were analyzed retrospectively for PD-1 expression in cryopreserved CD4+ and CD8+T cells collected at days 40, 90, 120, 150, 180, and 360 posttransplantation. HCT recipients with CMV disease (n=14) were compared with recipients with prolonged CMV infection, but no CMV disease (median duration of infection, 3 months; n=14) and with controls with no CMV infection who received similar transplants (n=22). The CMV disease group had a significantly higher mean fluorescein intensity of PD-1 in CD4+ (P < .05) and CD8+ (P < .05) lymphocytes at all time points studied. PD-1 expression also was significantly elevated in those with severe acute graft-versus-host disease (aGVHD), including the no-viremia group. The data suggest that PD-1 is induced by aGVHD even in the absence of CMV infection. This enhanced PD-1 expression during severe aGVHD and with CMV reactivation could explain the known role of aGVHD as a risk factor for CMV disease

Therapeutic targeting of the E3 ubiquitin ligase SKP2 in T-ALL

Timed degradation of the cyclin-dependent kinase inhibitor p27^(Kip1) by the E3 ubiquitin ligase F-box protein SKP2 is critical for T-cell progression into cell cycle, coordinating proliferation and differentiation processes. SKP2 expression is regulated by mitogenic stimuli and by Notch signaling, a key pathway in T-cell development and in T-cell acute lymphoblastic leukemia (T-ALL); however, it is not known whether SKP2 plays a role in the development of T-ALL. Here, we determined that SKP2 function is relevant for T-ALL leukemogenesis, whereas is dispensable for T-cell development. Targeted inhibition of SKP2 by genetic deletion or pharmacological blockade markedly inhibited proliferation of human T-ALL cells in vitro and antagonized disease in vivo in murine and xenograft leukemia models, with little effect on normal tissues. We also demonstrate a novel feed forward feedback loop by which Notch and IL-7 signaling cooperatively converge on SKP2 induction and cell cycle activation. These studies show that the Notch/SKP2/p27^(Kip1) pathway plays a unique role in T-ALL development and provide a proof-of-concept for the use of SKP2 as a new therapeutic target in T-cell acute lymphoblastic leukemia (T-ALL)

8-chloro-adenosine activity in FLT3-ITD acute myeloid leukemia

Nucleoside analogs represent the backbone of several distinct chemotherapy regimens for acute myeloid leukemia (AML) and combination with tyrosine kinase inhibitors has improved survival of AML patients, including those harboring the poor-risk FLT3-ITD mutation. Although these compounds are effective in killing proliferating blasts, they lack activity against quiescent leukemia stem cells (LSCs), which contributes to initial treatment refractoriness or subsequent disease relapse. The reagent 8-chloro-adenosine (8-Cl-Ado) is a ribose-containing, RNA-directed nucleoside analog that is incorporated into newly transcribed RNA rather than in DNA, causing inhibition of RNA transcription. In this report, we demonstrate antileukemic activities of 8-Cl-Ado in vitro and in vivo and provide mechanistic insight into the mode of action of 8-Cl-Ado in AML. 8-Cl-Ado markedly induced apoptosis in LSC, with negligible effects on normal stem cells. 8-Cl-Ado was particularly effective against AML cell lines and primary AML blast cells harboring the FLT3-ITD mutation. FLT3-ITD is associated with high expression of miR-155. Furthermore, we demonstrate that 8-Cl-Ado inhibits miR-155 expression levels accompanied by induction of DNA-damage and suppression of cell proliferation, through regulation of miR-155/ErbB3 binding protein 1(Ebp1)/p53/PCNA signaling. Finally, we determined that combined treatment of NSG mice engrafted with FLT3-ITD (+) MV4-11 AML cells with 8-Cl-Ado and the FLT3 inhibitor AC220 (quizartinib) synergistically enhanced survival, compared with that of mice treated with the individual drugs, suggesting a potentially effective approach for FLT3-ITD AML patients.Peer reviewe