CD8+ cutaneous T-cell lymphoma successfully treated with bexarotene: a case report and review of the literature

Primary cutaneous CD8+ cytotoxic T-cell lymphoma of the face with intraoral involvement, presenting facial nerve palsy after chemotherapy

The primary cutaneous (PC) CD8+ T-cell lymphoproliferative disorders (LPDs) comprise clinically and histologically heterogeneous entities including mycosis fungoides, lymphomatoid papulosis, hydroa-vacciniforme-like LPD, subcutaneous panniculitis-like T-cell lymphoma (TCL), PC acral CD8+ TCL, PC CD8+ aggressive epidermotropic cytotoxic TCL, and PC peripheral T-cell lymphoma, not otherwise specified (PTCL-NOS). We describe a 33-year-old man who presented progressive facial swelling and lower lip involvement one year ago. Microscopy revealed an atypical small to medium-sized lymphoid proliferation exhibiting perivascular accentuation, adnexotropism and apoptotic cell debris, without surface epithelium involvement. The tumor cells were positive for CD3, CD8, granzyme B, perforin, MUM1/IRF4, and TCR-BF1. The Ki-67 labeling index was 48%. EBER1/2 was negative. Additional studies confirmed localized disease. The diagnosis favored PC-PTCL-NOS. Two months after completing chemotherapy, right-sided facial nerve palsy was diagnosed. CD8+ T-cell LPDs should be considered in the differential diagnosis when assessing facial swelling with intraoral involvement. This article is protected by copyright. All rights reserved.

Partial trisomy 21 contributes to T-cell malignancies induced by JAK3-activating mutations in murine models

JAK3-activating mutations are commonly seen in chronic or acute hematologic malignancies affecting the myeloid, megakaryocytic, lymphoid, and natural killer (NK) cell compartment. Overexpression models of mutant JAK3 or pharmacologic inhibition of its kinase activity have highlighted the role that these constitutively activated mutants play in the T-cell, NK cell, and megakaryocytic lineages, but to date, the functional impact of JAK3 mutations at an endogenous level remains unknown. Here, we report a JAK3^A572V knockin mouse model and demonstrate that activated JAK3 leads to a progressive and dose-dependent expansion of CD8⁺ T cells in the periphery before colonization of the bone marrow. This phenotype is dependent on the γc chain of cytokine receptors and presents several features of the human leukemic form of cutaneous T-cell lymphoma (L-CTCL), including skin involvements. We also showed that the JAK3^A572V-positive malignant cells are transplantable and phenotypically heterogeneous in bone marrow transplantation assays. Interestingly, we revealed that activated JAK3 functionally cooperates with partial trisomy 21 in vivo to enhance the L-CTCL phenotype, ultimately leading to a lethal and fully penetrant disorder. Finally, we assessed the efficacy of JAK3 inhibition and showed that CTCL JAK3^A572V-positive T cells are sensitive to tofacitinib, which provides additional preclinical insights into the use of JAK3 inhibitors in these disorders. Altogether, this JAK3^A572V knockin model is a relevant new tool for testing the efficacy of JAK inhibitors in JAK3-related hematopoietic malignancies.

Synthesis and biological evaluation of retinoid-chalcones as inhibitors of colon cancer cell growth

Based on the observed anticancer activity of chalcones and retinoids, a novel class of retinoid-chalcone hybrids was designed and synthesized. As part of our ongoing studies to discover natural product based anticancer compounds, the retinoid-chalcone hybrids were tested against the colon cancer cell line HT-29. Retinoid like moiety was introduced through Friedel-Crafts alkylation of toluene. Among the synthesized compounds, the cyano derivative (E)-3-(3-oxo-3-(3,5,5,8,8-pentamethyl-5,6,7,8-tetrahydronaphthalen-2-yl)prop-1-enyl)benzonitrile 8 showed submicromolar inhibitory activity with an IC(50) of 0.66 μM.