Multifaceted adult T-cell leukemia/lymphoma in India: a case series

Melatonin: a modulator in metabolic rewiring in T-cell malignancies

Melatonin, (N-acetyl-5-methoxytryptamine) an indoleamine exerts multifaced effects and regulates numerous cellular pathways and molecular targets associated with circadian rhythm, immune modulation, and seasonal reproduction including metabolic rewiring during T cell malignancy. T-cell malignancies encompass a group of hematological cancers characterized by the uncontrolled growth and proliferation of malignant T-cells. These cancer cells exhibit a distinct metabolic adaptation, a hallmark of cancer in general, as they rewire their metabolic pathways to meet the heightened energy requirements and biosynthesis necessary for malignancies is the Warburg effect, characterized by a shift towards glycolysis, even when oxygen is available. In addition, T-cell malignancies cause metabolic shift by inhibiting the enzyme pyruvate Dehydrogenase Kinase (PDK) which in turn results in increased acetyl CoA enzyme production and cellular glycolytic activity. Further, melatonin plays a modulatory role in the expression of essential transporters (Glut1, Glut2) responsible for nutrient uptake and metabolic rewiring, such as glucose and amino acid transporters in T-cells. This modulation significantly impacts the metabolic profile of T-cells, consequently affecting their differentiation. Furthermore, melatonin has been found to regulate the expression of critical signaling molecules involved in T-cell activations, such as CD38, and CD69. These molecules are integral to T-cell adhesion, signaling, and activation. This review aims to provide insights into the mechanism of melatonin's anticancer properties concerning metabolic rewiring during T-cell malignancy. The present review encompasses the involvement of oncogenic factors, the tumor microenvironment and metabolic alteration, hallmarks, metabolic reprogramming, and the anti-oncogenic/oncostatic impact of melatonin on various cancer cells.

Bowenoid papulosis unveiling a rare cause of immunosuppression

Bowenoid papulosis (BP) is a premalignant condition usually caused by oncogenic types of human papillomavirus (HPV) presenting clinically as warty genital papules. Adult T-cell leukaemia-lymphoma (ATLL) is a peripheral T-cell leukaemia-lymphoma caused by the retrovirus, human T-cell lymphotropic virus 1 (HTLV-1). We report a case of BP initially mistaken as genital warts; on detailed evaluation the patient had features of chronic immunosuppression. The presence of leukaemic cells in the peripheral blood, bone marrow and skin along with a positive HTLV-1 serology confirmed the diagnosis of ATLL.

A Clinicopathological Analysis of Primary Cutaneous Lymphomas: A 6-year Observational Study at a Tertiary Care Center of South India

BACKGROUND

Little data are available concerning clinical and pathological patterns of cutaneous lymphomas in India.

AIM

To analyze the clinical and histopathological characteristics of cutaneous lymphomas in Indian patients.

MATERIALS AND METHODS

This is a single-center, prospective, observational study carried out from January 1, 2010, to December 31, 2015. The patients underwent clinical examination, human T-cell lymphotropic virus-1 (HTLV-1) screening, skin biopsy with hematoxylin and eosin and immunohistochemistry staining.

RESULTS

Among 35 cases, 33 (94.3%) were T-cell, and 2 (5.7%) were B-cell lymphomas. The mean age was 52.66, and the male to female ratio was 2.5:1. The most common types of T-cell lymphomas included mycosis fungoides (MF) (57.1%) followed by adult T-cell lymphoma/leukemia (ATL) (17.1%). Primary cutaneous peripheral T-cell lymphoma not otherwise specified was diagnosed in 17.1% and anaplastic large cell lymphoma in 2.9%. The morphological types of MF included polymorphic, poikilodermatous, folliculotropic, hypopigmented, hyperpigmented, mixed, and purpuric. Skin manifestations of ATL included ulcerated plaques and erythroderma. Epidermotropism was very marked in ATL (83.3%) than in MF (70%). Larger Pautrier's microabscess was noted in ATL compared to smaller ones in MF. Markedly dense, diffuse infiltrate of atypical cells was noted in ATL in contrast to mild to moderate nodular or perivascular infiltrate in MF. ATL had an extremely poor prognosis.

LIMITATIONS

Identification of DNA integration of HTLV-1 by Southern blot could not be analyzed, and the number of cases studied is limited.

CONCLUSIONS

The study showed unique patterns of subtypes of cutaneous lymphomas in our country. Variations in the clinical pattern and histopathological analysis will help to differentiate T-cell lymphoma types which have prognostic implications.