Cutaneous T-cell lymphoma

CCL27 Signaling in the Tumor Microenvironment

Chemokines are a group of small proteins which play an important role in leukocyte migration and invasion. They are also involved in the cellular proliferation and migration of tumor cells.Chemokine CCL27 (cutaneous T cell-attracting chemokine, CTACK) is mainly expressed by keratinocytes of the normal epidermis. It is well known that this chemokine plays an important role in several inflammatory diseases of the skin, such as atopic dermatitis, contact dermatitis, and psoriasis. Moreover, several studies have shown an association between CCL27 expression and a variety of neoplasms including skin cancer.In this chapter, we address the role of chemokine CCL27 in the tumor microenvironment in the most relevant cancers of the skin and other anatomical locations. We also make a brief comment on future perspectives and the potential relation of CCL27 with different immunotherapeutic modalities.

Non-Classic Signs of Sézary Syndrome: A Review

The majority of patients with Sézary syndrome (SS) present with classic symptoms of erythroderma, lymphadenopathy, and pruritus. However, there have been numerous reports of patients with SS who have non-classic signs. In this review, we report the less common clinical presentations of SS and discuss their relevant treatments. Our search included all literature on SS since 2008, the year the World Health Organization (WHO) incorporated the diagnostic criteria for SS into the WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues. We reviewed 896 articles and identified 505 patients with non-classic presentations of SS. Of these 505 patients, the most common non-classic signs of SS were keratoderma, onychodystrophy, alopecia, leonine facies, and ectropion. Given the aggressive and highly symptomatic nature of SS, it is imperative that clinicians recognize the less common signs of the disease to prevent delays in diagnosis and treatment. To our knowledge, this is the first review of the clinical variations of SS with a focus on non-classic signs and symptoms.

miRNA‑135a regulates Hut78 cell proliferation via the GATA‑3/TOX signaling pathway

The present study investigated the role of microRNA‑135a (miR‑135a) in cutaneous T‑cell lymphoma (CTCL) proliferation. Compared with the normal T lymphocyte control cell line, the mRNA and protein levels of GATA binding protein 3 (GATA‑3) were markedly increased in the Hut78 cell line and miR‑135a was markedly decreased (P<0.05). Based on bioinformatics, the target gene of miR‑135a was identified as GATA‑3. Dual luciferase and pre‑miR‑135a assays showed that miR‑135a regulated the translation of GATA‑3. In addition, the overexpression of miR‑135a mimics decreased the protein levels of GATA‑3 and thymocyte selection‑associated high mobility group box (TOX). The substantially increased mRNA and protein levels of GATA‑3 may be associated with the downregulation of miR‑135a, leading to T‑cell deregulation and proliferation through GATA‑3/TOX regulation and subsequently causing CTCL.

Classification and clinical features in 88 cases of equine cutaneous lymphoma

Equine cutaneous lymphoma is an uncommon disease that can present with variable clinical signs, immunosuppression, and rapid systemic disease progression. Various subtypes of equine lymphoma have been described and classified according to a veterinary adaptation of the World Health Organization classification system, but little data is available regarding the association between lymphoma subtypes and epidemiological criteria and/or clinical outcome. The objective of the current study was to classify previously diagnosed cases of equine cutaneous lymphoma and correlate subtypes with clinical data to investigate epidemiological trends and prognostic implications. Results from the study confirm T-cell–rich, large B-cell lymphoma (TCRLBCL) as the predominant subtype in equine cutaneous lymphoma. Cutaneous T-cell lymphoma (CTCL) was the second most common phenotype in the current study. To the authors’ knowledge, a description of the morphological and immunohistochemical features of CTCL in horses, an epitheliotropic neoplasm similar to the cutaneous epitheliotropic lymphoma variant (mycosis fungoides) observed in human beings and canids, has not been previously described. Less common lymphoma subtypes identified in the study include diffuse large B-cell lymphoma and anaplastic large T-cell lymphoma. Quarter Horses almost exclusively developed TCRLBCL, while the frequency of CTCL was increased significantly in Thoroughbreds compared with other breeds. TCRLBCLs more frequently presented as multiple masses while CTCLs were more often solitary nodules. When multiple regions of the body were affected, 100% of cases were TCRBCL. Finally, there was an observable trend for longer survival in cases of TCRLBCL without local recurrence, suggesting adequate surgical excision may be an effective treatment modality.

STAT3 knockdown by siRNA induces apoptosis in human cutaneous T-cell lymphoma line Hut78 via downregulation of Bcl-xL

Cutaneous T-cell lymphomas (CTCLs) are non-Hodgkin's lymphomas resulting from clonal expansion and localization of malignant T-lymphocytes to the skin. CTCL cells have defective apoptosis. Signal transducers and activators of transcription (STAT) are a family of transcription factors known to play important roles in the development and progression of several human cancers by promoting cell proliferation and protecting against apoptosis. In this study, we investigated the specific role of STAT3, a major component of the STAT family, in growth and survival of human CTCL cell line Hut78. Western immunoblot analysis showed elevated expression of STAT3 and phospho-STAT3(Y705) in human CTCL cells as compared to freshly isolated peripheral blood lymphocytes (PBLs). Specific knockdown of STAT3 expression in Hut78 cells by RNA interference induced morphological and biochemical changes indicating apoptotic cell death. Moreover, STAT3 inhibition downregulated the expression of Bcl2 family of anti-apoptotic gene Bcl-xL. These observations suggest that STAT3 is required for the survival of CTCL cells and strongly indicate that targeting STAT3 using siRNA techniques may serve a novel therapeutic strategy for the treatment of CTCL.

Increased malignancy risk in the cutaneous T-cell lymphoma patient population

BACKGROUND

Cutaneous T-cell lymphoma (CTCL) has been associated with increased risk for second malignancies. However, the degree of risk and types of second cancers detected have been inconsistent in previous studies.

PATIENTS AND METHODS

To further characterize the risk for malignancy associated with CTCL, patients treated for CTCL at M. D. Anderson Cancer Center in Houston, Texas, between November 1979 and November 1999 were assessed for the occurrence of additional cancers by analysis of institutional tumor registry data.

RESULTS

Of 672 patients with CTCL, 112 had > or = 1 additional cancer, 37 occurring after the diagnosis of CTCL. This represents a significant elevation in cancer prevalence and incidence, with a 1.79-fold risk (95% CI, 1.22-2.39) for developing cancer after CTCL. An excess of Hodgkin and non-Hodgkin lymphoma, acute myeloid leukemia, and vulvar cancers was seen.

CONCLUSION

These data provide evidence for an increased overall incidence of second malignancy in CTCL, particularly with respect to other lymphoproliferative malignancies. Appropriate monitoring for the early detection of second cancers might be warranted in patients with CTCL.

Sézary Syndrome in a Cat

Sézary syndrome is an uncommon leukemic variant of cutaneous lymphoma in cats. This cat had recurrent dermatitis with erythematous, pruritic plaques. Multiple skin imprints and biopsy samples were obtained over a 6-month period, and histopathological findings were consistent initially with eosinophilic miliary dermatitis and later with erythema multiforme. One week before death, Sézary cells were identified in the peripheral blood that expressed cluster of differentiation (CD)3 and CD8 antigens. Massive infiltration of CD3+ lymphocytes was noted in the skin and multiple internal tissues by histopathological examination. This case demonstrates the difficulty in diagnosing cutaneous lymphoma early in the disease course.

Mycosis fungoides: a dermatological masquerader

Mycosis fungoides (MF), a low-grade lymphoproliferative disorder, is the most common type of cutaneous T-cell lymphoma. Typically, neoplastic T cells localize to the skin and produce patches, plaques, tumours or erythroderma. Diagnosis of MF can be difficult due to highly variable presentations and the sometimes nonspecific nature of histological findings. Molecular biology has improved the diagnostic accuracy. Nevertheless, clinical experience is of substantial importance as MF can resemble a wide variety of skin diseases. We performed a literature review and found that MF can mimic >50 different clinical entities. We present a structured framework of clinical variations of classical, unusual and distinct forms of MF. Distinct subforms such as ichthyotic MF, adnexotropic (including syringotropic and folliculotropic) MF, MF with follicular mucinosis, granulomatous MF with granulomatous slack skin and papuloerythroderma of Ofuji are delineated in more detail.

CCR10 is expressed in cutaneous T-cell lymphoma

Cutaneous T-cell lymphoma (CTCL) is characterized by recruitment of malignant T-cell clones into the skin. The mechanisms involved in tumor homing are still not fully elucidated, though chemokines and chemokine receptors have been suggested to play a role in the pathogenesis. Here, we demonstrate extensive expression of CCR10 in skin biopsies of patients with Sezary syndrome (SS, n = 3), mycosis fungoides (MF, n = 2) and unspecified CTCL (n = 3). In addition, we expand prior findings of CXCR3 expression in MF to other entities of CTCL. Expression of CCR5 was detected in 2 of the examined skin biopsies. The functionality of CCR10 and CXCR3 in SS was demonstrated using the SS T-cell line HUT78. Our data support a potential role of CXCR3 in CTCL and strongly suggest that CCR10 and its ligand CCL27 may contribute to the skin infiltration of malignant T-cells in this group of lymphoproliferative disorders.

In vivo activation of STAT3 in cutaneous T-cell lymphoma. Evidence for an antiapoptotic function of STAT3

A characteristic feature of neoplastic transformation is a perpetual activation of oncogenic proteins. Here, we studied signal transducers and activators of transcription (STAT) in patients with mycosis fungoides (MF)/cutaneous T-cell lymphoma (CTCL). Malignant lymphocytes in dermal infiltrates of CTCL tumors showed frequent and intense nuclear staining with anti-PY-STAT3 antibody, indicating a constitutive activation of STAT3 in vivo in tumor stages. In contrast, only sporadic and faint staining was observed in indolent lesions of patch and plaque stages of MF. Moreover, neoplastic lymphocytes in the epidermal Pautrier abscesses associated with early stages of MF did not express activated STAT3. To address the role of STAT3 in survival/apoptosis, CTCL tumor cells from an advanced skin tumor were transfected with either wild-type STAT3 (STAT3wt) or dominant-negative STAT3 (STAT3D). Forced inducible expression of STAT3D triggered a significant increase in tumor cells undergoing apoptosis, whereas forced expression of STAT3wt or empty vector had no effect. In conclusion, a profound in vivo activation of STAT3 is observed in MF tumors but not in the early stages of MF. Moreover, STAT3 protects tumor cells from apoptosis in vitro. Taken together, these findings suggest that STAT3 is a malignancy factor in CTCL.