Angioimmunoblastic T-cell lymphoma and correlated neoplasms with T-cell follicular helper phenotype: from molecular mechanisms to therapeutic advances

Complete hematologic response in a patient with multiple pretreated angioimmunoblastic T-cell lymphoma after belinostat therapy followed by allogeneic stem cell transplantation: A case report

Key Clinical Message

Belinostat therapy followed by hematopoietic stem cell transplantation is a promising salvage strategy for heavily pretreated patients with peripheral T-cell lymphoma.

Abstract

Effective treatments for peripheral T-cell lymphoma in the relapsed and refractory (r/r) setting are limited. However, with the development and approval of innovative therapies, effective therapeutic options are becoming available for this patient population. This case report describes the treatment course of a patient with multiple r/r nodal follicular T-helper cell lymphoma of angioimmunoblastic type. Treatment with the histone deacetylase inhibitor belinostat as bridging, enabled allogeneic stem cell transplantation and resulted in a durable complete hematologic response for at least 21 months post-transplantation.

Romidepsin Plus Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone Versus Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone in Patients With Previously Untreated Peripheral T-Cell Lymphoma: Final Analysis of the Ro-CHOP Trial

Clinical trials frequently include multiple end points that mature at different times. The initial report, typically based on the primary end point, may be published when key planned co-primary or secondary analyses are not yet available. Clinical Trial Updates provide an opportunity to disseminate additional results from studies, published in JCO or elsewhere, for which the primary end point has already been reported.The primary analysis of the Ro-CHOP phase III randomized controlled trial (ClinicalTrials.gov identifier: NCT01796002) established that romidepsin (Ro) plus cyclophosphamide, doxorubicin, vincristine, prednisone (CHOP) did not yield an increased efficacy compared with CHOP alone as first-line treatment of peripheral T-cell lymphoma. We report the planned final analysis 5 years after the last patient enrolled. With a median follow-up of 6 years, median progression-free survival (PFS) was 12.0 months compared with 10.2 months (hazard ratio [HR], 0.79 [95% CI, 0.62 to 1.005]; P = .054), while median overall survival was 62.2 months (35.7-86.6 months) and 43.8 months (30.1-70.2 months; HR, 0.88 [95% CI, 0.68 to 1.14]; P = .324) in the Ro-CHOP and CHOP arms, respectively. In an exploratory analysis, the median PFS in the centrally reviewed follicular helper T-cell lymphoma subgroup was significantly longer in the Ro-CHOP arm (19.5 v 10.6 months, HR, 0.703 [95% CI, 0.502 to 0.985]; P = .039). Second-line treatments were given to 251 patients with a median PFS2 and OS2 after relapse or progression of 3.3 months and 11.5 months, respectively. Within the limits of highly heterogeneous second-line treatments, no specific regimen seemed to provide superior disease control. However, a potential benefit was observed with brentuximab vedotin in association with chemotherapy even after excluding anaplastic large-cell lymphoma subtype or after adjusting for histology and international prognostic index in a multivariate model (HR for PFS, 0.431 [95% CI, 0.238 to 0.779]; P = .005).

Enteric associated T-cell lymphoma in a mule

A 25-year-old female mule weighing 336 kg was referred with a history of lethargy, abdominal discomfort, anorexia, and constipation in the previous 24 hours. On admission, decreased intestinal borborygmi and distended small intestinal loops were detected by auscultation and rectal palpation, respectively. On rectal examination a firm, irregular surface, and pedunculated mass were detected in the middle-caudal region of the abdomen. Transrectal ultrasonography revealed the mass was highly vascularized with heterogeneous tissue density. On exploratory celiotomy two neoplastic masses were observed, one in the jejunoileal junction obstructing the intestinal flow and the second in the dorsal part of the jejunal mesentery, unable to be exposed and resected. An enterectomy was conducted, and the intestinal mass was removed. The mass was pale with hemorrhagic areas and 12 cm in diameter. Histopathology and immunohistochemistry confirmed a diagnosis of enteric associated T cell lymphoma subtype 2. The mule died suddenly 43 days later.

Inhibition of choline metabolism in an angioimmunoblastic T-cell lymphoma preclinical model reveals a new metabolic vulnerability as possible target for treatment

BACKGROUND

Angioimmunoblastic T-cell lymphoma (AITL) is a malignancy with very poor survival outcome, in urgent need of more specific therapeutic strategies. The drivers of malignancy in this disease are CD4+ follicular helper T cells (Tfh). The metabolism of these malignant Tfh cells was not yet elucidated. Therefore, we decided to identify their metabolic requirements with the objective to propose a novel therapeutic option.

METHODS

To reveal the prominent metabolic pathways used by the AITL lymphoma cells, we relied on metabolomic and proteomic analysis of murine AITL (mAITL) T cells isolated from our established mAITL model. We confirmed these results using AITL patient and healthy T cell expression data.

RESULTS

Strikingly, the mAITL Tfh cells were highly dependent on the second branch of the Kennedy pathway, the choline lipid pathway, responsible for the production of the major membrane constituent phosphatidylcholine. Moreover, gene expression data from Tfh cells isolated from AITL patient tumors, confirmed the upregulation of the choline lipid pathway. Several enzymes involved in this pathway such as choline kinase, catalyzing the first step in the phosphatidylcholine pathway, are upregulated in multiple tumors other than AITL. Here we showed that treatment of our mAITL preclinical mouse model with a fatty acid oxydation inhibitor, significantly increased their survival and even reverted the exhausted CD8 T cells in the tumor into potent cytotoxic anti-tumor cells. Specific inhibition of Chokα confirmed the importance of the phosphatidylcholine production pathway in neoplastic CD4 + T cells, nearly eradicating mAITL Tfh cells from the tumors. Finally, the same inhibitor induced in human AITL lymphoma biopsies cell death of the majority of the hAITL PD-1high neoplastic cells.

CONCLUSION

Our results suggest that interfering with choline metabolism in AITL reveals a specific metabolic vulnerability and might represent a new therapeutic strategy for these patients.