Keratinocytes Present Staphylococcus aureus Enterotoxins and Promote Malignant and Nonmalignant T Cell Proliferation in Cutaneous T-Cell Lymphoma.

Cutaneous T-cell lymphoma is characterized by malignant T cells proliferating in a unique tumor microenvironment dominated by keratinocytes (KCs). Skin colonization and infection by Staphylococcus aureus are a common cause of morbidity and are suspected of fueling disease activity. In this study, we show that expression of HLA-DRs, high-affinity receptors for staphylococcal enterotoxins (SEs), by KCs correlates with IFN-γ expression in the tumor microenvironment.

Staphylococcus aureus induces drug resistance in cancer T cells in Sézary syndrome.

Patients with Sézary syndrome (SS), a leukemic variant of cutaneous T-cell lymphoma (CTCL), are prone to Staphylococcus aureus infections and have a poor prognosis due to treatment resistance. Here, we report that S aureus and staphylococcal enterotoxins (SE) induce drug resistance in malignant T cells against therapeutics commonly used in CTCL. Supernatant from patient-derived, SE-producing S aureus and recombinant SE significantly inhibit cell death induced by histone deacetylase (HDAC) inhibitor romidepsin in primary malignant T cells from patients with SS.

Endolysin Inhibits Skin Colonization by Patient-Derived Staphylococcus Aureus and Malignant T-Cell Activation in Cutaneous T-Cell Lymphoma.

Staphylococcus aureus is suspected to fuel disease activity in cutaneous T-cell lymphomas. In this study, we investigate the effect of a recombinant, antibacterial protein, endolysin (XZ.700), on S.

Malignant T cells induce skin barrier defects through cytokine-mediated JAK/STAT signaling in cutaneous T-cell lymphoma.

Cutaneous T-cell lymphoma (CTCL) is a devastating lymphoid malignancy characterized by the accumulation of malignant T cells in the dermis and epidermis. Skin lesions cause serious symptoms that hamper quality of life and are entry sites for bacterial infection, a major cause of morbidity and mortality in advanced diseases. The mechanism driving the pathological processes that compromise the skin barrier remains unknown.

Mild to moderate atopic dermatitis severity can be reliably assessed using smartphone-photographs taken by the patient at home: A validation study.

Background: The use of photographs to diagnose and monitor skin diseases is gaining ground.

Objectives: To investigate the validity and reliability of photographic assessments of atopic dermatitis (AD) severity.

Methods: AD severity was evaluated in the clinic by two assessors using the Eczema Area and Severity Index (EASI), SCOring Atopic Dermatitis (SCORAD), and Investigator's Global Assessment (IGA).

Staphylococcus aureus Induces Signal Transducer and Activator of Transcription 5‒Dependent miR-155 Expression in Cutaneous T-Cell Lymphoma.

Staphylococcal enterotoxins are believed to fuel disease activity in cutaneous T-cell lymphoma. Recent data support this by showing that antibiotics inhibit malignant T cells in skin lesions in mycosis fungoides and Sézary syndrome, the most common forms of cutaneous T-cell lymphoma. Yet, it remains incompletely characterized how staphylococcal enterotoxins fuel disease activity.

Photochemotherapy Induces Interferon Type III Expression via STING Pathway.

DNA-damaging cancer therapies induce interferon expression and stimulate the immune system, promoting therapy responses. The immune-activating STING (Stimulator of Interferon Genes) pathway is induced when DNA or double-stranded RNA (dsRNA) is detected in the cell cytoplasm, which can be caused by viral infection or by DNA damage following chemo- or radiotherapy. Here, we investigated the responses of cutaneous T-cell lymphoma (CTCL) cells to the clinically applied DNA crosslinking photochemotherapy (combination of 8-methoxypsoralen and UVA light; 8-MOP + UVA).

Chemotherapeutic treatment is associated with Notch1 induction in cutaneous T-cell lymphoma.

The Notch pathway is important for survival of cutaneous T-cell lymphoma (CTCL) cells. We investigated the effect of chemotherapy (doxorubicin, etoposide, and gemcitabine) and radiation modalities on Notch signaling in CTCL cell lines. Chemotherapy induced Notch1 expression at the mRNA and protein level in MyLa2000 and Hut78.

Low-dose (10-Gy) total skin electron beam therapy for cutaneous T-cell lymphoma: an open clinical study and pooled data analysis.

Purpose: Cutaneous T-cell lymphomas (CTCLs) are dominated by mycosis fungoides (MF) and Sézary syndrome (SS), and durable disease control is a therapeutic challenge. Standard total skin electron beam therapy (TSEBT) is an effective skin-directed therapy, but the possibility of retreatments is limited to 2 to 3 courses in a lifetime due to skin toxicity. This study aimed to determine the clinical effect of low-dose TSEBT in patients with MF and SS.

The importance of Notch signaling in peripheral T-cell lymphomas.

Peripheral T-cell lymphomas (PTLs) represent an area of high medical need. Previously, we demonstrated high expression of Notch, a known oncogene, in primary cutaneous anaplastic large cell lymphoma (ALCL). In this study, we performed immunohistochemical staining for Notch1 in lymph nodes from PTL not otherwise specified (PTL-NOS) and systemic ALCL (ALK+ and ALK-) and report a similar distribution among the three subgroups: Negative, moderate and strong expression was, respectively, 18%, 27% and 55% for PTL-NOS (33 cases), 20%, 0% and 80% for ALCL ALK+ (10 cases) and 45%, 22% and 33% for ALCL ALK- (nine cases) (p > 0.

MDM2 inhibitor nutlin-3a induces apoptosis and senescence in cutaneous T-cell lymphoma: role of p53.

P53 is rarely mutated in cutaneous T-cell lymphoma (CTCL) and is therefore a promising target for innovative therapeutic approaches. Nutlin-3a is an inhibitor of MDM2 (human homolog of murine double minute 2), which disrupts its interaction with p53, leading to the stabilization and activation of p53. To investigate the potential therapeutic use of nutlin-3a in CTCL, we screened CTCL lines Hut-78, SeAx, MyLa2000, Mac1, and Mac2a by measuring p53 levels after nutlin-3a treatment.

Total skin electron beam therapy for cutaneous T-cell lymphoma: a nationwide cohort study from Denmark.

Background: Total skin electron beam therapy (TSEBT) is an effective palliative treatment for cutaneous T-cell lymphoma (CTCL). In the present study we reviewed the clinical response to TSEBT in Danish patients with CTCL.

Material And Methods: This retrospective study included 35 patients with CTCL treated with TSEBT in Denmark from 2001 to 2008 and followed for a median time of 7.

Notch1 as a potential therapeutic target in cutaneous T-cell lymphoma.

Deregulation of Notch signaling has been linked to the development of T-cell leukemias and several solid malignancies. Yet, it is unknown whether Notch signaling is involved in the pathogenesis of mycosis fungoides and Sézary syndrome, the most common subtypes of cutaneous T-cell lymphoma. By immunohistochemistry of 40 biopsies taken from skin lesions of mycosis fungoides and Sézary syndrome, we demonstrated prominent expression of Notch1 on tumor cells, especially in the more advanced stages.

Growth dynamics and cyclin expression in cutaneous T-cell lymphoma cell lines.

We have investigated cell growth dynamics and cyclins B1 and E expression in cell lines derived from mycosis fungoides (MyLa), Sézary syndrome (SeAx), and CD30(+) lympho-proliferative diseases (Mac1, Mac2a, JK). Mac1 and Mac2a had the highest growth rate (doubling time 18-28 h, >90% cycling cells) whereas SeAx was proliferating slowly (doubling time 55 h, approximately 35% cycling cells). Expression of cyclin B1 correlated positively with doubling time whereas expression of cyclin E was unscheduled and constant across the investigated cell lines.

A prospective, open-label study of low-dose total skin electron beam therapy in mycosis fungoides.

Purpose: To determine the effect of low-dose (4 Gy) total skin electron beam therapy as a second-line treatment of Stage IB-II mycosis fungoides in a prospective, open-label study.

Methods And Materials: Ten patients (6 men, 4 women, average age 68.7 years [range, 55-82 years]) with histopathologically confirmed mycosis fungoides T2-T4 N0-N1 M0 who did not achieve complete remission or relapsed within 4 months after treatment with psoralen plus ultraviolet-A were included.

Putative cancer stem cells in cutaneous malignancies.

Recent experimental data offer convincing evidence for the existence of cancer stem cells in leukaemia, brain tumors and breast cancer. These cells are responsible for the maintenance of tumor growth and relapses after cytoreductive treatments. This paper provides a brief overview of current data supporting the idea of cancer stem cells in the pathogenesis of cutaneous malignancies, including skin carcinoma, malignant melanoma and cutaneous T-cell lymphoma.