Gene arrays in lymphoma: Where will they fit in?

Phase 1 trial of carfilzomib in relapsed/refractory peripheral T-cell lymphoma

Peripheral T-cell lymphomas (PTCL) are a unique subset of lymphomas with a poor prognosis due to limited treatment options. We performed a phase 1 study of carfilzomib in patients with relapsed/refractory PTCL to determine the safety profile and the maximum tolerated dose (MTD) of this agent. The study was a classical 3 + 3 phase 1 design with intra-patient dose escalation allowed beginning on day 8 of cycle 1 and subsequently. Dose-limiting toxicity (DLT) was defined as the occurrence of any grade 3/4 adverse event. Carfilzomib was given on days 1, 2, 8, 9, 15, and 16 of a 28-day cycle. Fifteen patients were enrolled from 3 centers. The median age of patients was 62. The median number of prior therapies for subjects on this trial was five. The MTD of carfilzomib was 36 mg/m². Dose-limiting toxicities included anemia and sepsis. Serious adverse events were seen in 45% of patients. Single-agent carfilzomib leads to a complete response in one patient and a partial response in one patient. Overall, the drug was reasonably tolerated for a heavily pretreated population, but the limited response rate and short duration of response demonstrate a lack of promise for carfilzomib as a single agent in this patient population.

Molecular signatures to improve diagnosis in peripheral T-cell lymphoma and prognostication in angioimmunoblastic T-cell lymphoma

Peripheral T-cell lymphoma (PTCL) is often challenging to diagnose and classify. Gene expression profiling was performed on 144 cases of PTCL and natural killer cell lymphoma and robust molecular classifiers were constructed for angioimmunoblastic T-cell lymphoma (AITL), anaplastic lymphoma kinase-positive (ALK(+)) anaplastic large-cell lymphoma (ALCL), and adult T-cell leukemia/lymphoma. PTCL-unclassifiable was molecularly heterogeneous, but we were able to identify a molecular subgroup with features of cytotoxic T lymphocytes and a poor survival compared with the remaining PTCL-not otherwise specified cases. Many of the pathologic features and substantial components of the molecular signature of AITL are contributed by the follicular dendritic cells, B-cell, and other stromal components. The expression of Th17-associated molecules in ALK(+) ALCL was noted and may represent aberrant activation of Th17-cell differentiation by abnormal cytokine secretion. Adult T-cell leukemia/lymphoma has a homogeneous molecular signature demonstrating high expression of human T-lymphotropic virus type 1-induced genes. These classifiers reflect the biology of the tumor cells as well as their microenvironment. We also constructed a molecular prognosticator for AITL that appears to be largely related to the microenvironmental signature, and the high expression of 2 immunosuppressive signatures are associated with poor outcome. Oncogenic pathways and tumor-host interactions also were identified, and these findings may lead to better therapies and outcome in the future.