Novel therapies in peripheral T-cell lymphomas

Non-Hodgkin's B-cell lymphoma: advances in molecular strategies targeting drug resistance

Non-Hodgkin's lymphoma (NHL) is a heterogeneous class of cancers displaying a diverse range of biological phenotypes, clinical behaviours and prognoses. Standard treatments for B-cell NHL are anthracycline-based combinatorial chemotherapy regimens composed of cyclophosphamide, doxorubicin, vincristine and prednisolone. Even though complete response rates of 40-50% with chemotherapy can be attained, a substantial proportion of patients relapse, resulting in 3-year overall survival rates of about 30%. Relapsed lymphomas are refractory to subsequent treatments with the initial chemotherapy regimen and can exhibit cross-resistance to a wide variety of anticancer drugs. The emergence of acquired chemoresistance thus poses a challenge in the clinic preventing the successful treatment and cure of disseminated B-cell lymphomas. Gene-expression analyses have increased our understanding of the molecular basis of chemotherapy resistance and identified rational targets for drug interventions to prevent and treat relapsed/refractory diffuse large B-cell lymphoma. Acquisition of drug resistance in lymphoma is in part driven by the inherent genetic heterogeneity and instability of the tumour cells. Due to the genetic heterogeneity of B-cell NHL, many different pathways leading to drug resistance have been identified. Successful treatment of chemoresistant NHL will thus require the rational design of combinatorial drugs targeting multiple pathways specific to different subtypes of B-cell NHL as well as the development of personalized approaches to address patient-to-patient genetic heterogeneity. This review highlights the new insights into the molecular basis of chemorefractory B-cell NHL that are facilitating the rational design of novel strategies to overcome drug resistance.

Circulating levels of TNF receptor II are prognostic for patients with peripheral T-cell non-Hodgkin lymphoma

PURPOSE

Peripheral T-cell non-Hodgkin lymphomas (T-NHL) represent a small but heterogeneous and clinically aggressive subset of NHLs with a poor outcome. Cytokines or their receptors might be associated with the clinical outcome of these lymphomas. Therefore, we tested whether gene variations and serum levels of soluble TNF receptor (TNFR)I (sTNFRI), sTNFRII, interleukin (IL)-10, or sIL-4R are predictive for treatment response in T-NHLs.

EXPERIMENTAL DESIGN

Peripheral blood DNA from 117 patients with T-NHL treated in prospective clinical trials was subjected to genotyping analysis. Whenever possible, pretreatment sera were obtained, and circulating levels of sTNFRI, sTNFRII, IL-10, and sIL-4R were determined with a specific capture enzyme-linked immunoassay.

RESULTS

Patients characterized by TNFRI-609GG (rs4149570) showed a trend toward better event free survival [EFS; univariate: P = 0.041; multivariate: HR, 1.76; confidence interval (CI), 0.99-3.14 with P = 0.056]. A protective role of IL-10-1087A, -824T, and -597A reported in another study was not confirmed in our cohort. Patients with circulating levels of soluble TNFRII ≥2.16 ng/mL had a 2.07-fold increased relative risk for shorter overall survival (OS; univariate: P = 0.0034; multivariate: HR, 2.07; CI, 0.92-4.70 with P = 0.081) and a 2.49-fold higher risk for shorter EFS (univariate: P = 0.00068; multivariate: HR, 2.49; CI, 1.22-5.08 with P = 0.012). Elevations of circulating levels of sTNFRI, IL-10, and sIL-4R are frequent, but the clinical response in these patients is not significantly different.

CONCLUSIONS

Our findings suggest a critical role for TNF-TNFR signaling for the clinical outcome of patients with peripheral T-NHLs.

Novel therapeutics for aggressive non-Hodgkin's lymphoma

Application of advances in genomic and proteomic technologies has provided molecular insights into distinct types of aggressive B- and T-cell non-Hodgkin's lymphomas (NHLs). This has led to the validation of novel biomarkers of classification, risk-stratification, and druggable targets. The promise of novel treatments from genomic research has been slow to materialize because of the lack of a therapeutic signature for the distinct NHL subtypes. Patients with lymphoma with aggressive disease urgently require the development of novel therapies on the basis of investigation of dysregulated intracellular oncogenic processes that arise during lymphomagenesis. Although monoclonal antibodies have made significant contributions to the armamentarium of B-cell NHL therapy (eg, anti-CD20), parallel development of small-molecule inhibitors (SMIs) to intracellular targets has lagged behind. Despite these deficiencies, several promising anti-NHL therapies are in development that target immune kinases of the B-cell receptor signaling pathway, mammalian target of rapamycin complex, proteasome, DNA/histone epigenetic complex, antiapoptosis, neoangiogenesis, and immune modulation. This review focuses on novel SMI therapeutic strategies that target overlapping core oncogenic pathways in the context of the 10 hallmarks of cancer. Furthermore, we have developed the concept of a therapeutic signature using the 10 hallmarks of cancer, which may be incorporated into novel phase I/II drug development programs.