tretinoin and Lymphoma--T-Cell--Cutaneous

Histone deacetylase inhibitors comprise a variety of natural and synthetic compounds, which have in common that they inhibit enzymes that mediate the removal of acetyl groups from a range of proteins, including nucleosomal histones. Histone deacetylase inhibitors have anti-cancer activities in vitro and in vivo and are used in the clinic for the treatment of advanced cutaneous T cell lymphoma. The molecular pathways targeted by these compounds are discussed with an emphasis on the effects of these compounds on retinoic acid signaling.

Topics: Animals; Antineoplastic Agents; DNA Methylation; Enzyme Inhibitors; Epigenesis, Genetic; Histone Deacetylase Inhibitors; Histone Deacetylases; Histones; Humans; Lymphoma, T-Cell, Cutaneous; Models, Biological; Neoplasms; Tretinoin

Treatment of refractory/relapsed cutaneous T-cell lymphoma (CTCL) remains controversial, most studies included a few patients with a short follow-up. Previously, we performed two small studies employing interferon alpha 2b (IFN) combined with low doses of methotrexate (MTX) or retinoids. Thus, we conducted an open-label clinical trial to assess the benefit and toxicity of the two mentioned regimens in a large number of patients with a longer follow-up of the treatment of refractory/relapsed CTCL.. Three-hundred and seventy-seven patients with refractory/relapsed, pathologically confirmed, CTCL, with advanced stages and at least treated with two previous effective regimens in CTCL, were randomized to receive IFN and low doses of MTX compared with IFN and all trans-retinoid acid during 6 months; if a complete response (CR) was not achieved, treatment was continued until 12 months in both arms. At this time, if patient achieves CR, MTX or retinoid was stopped, and the patient continues to receive IFN until progression disease or toxicity. One-hundred and eight patients received IFN for more than 5 years.. Toxicity was minimal and well tolerated, no patients needed to modify the administration of IFN secondary to toxicity. The overall complete response was achieved 80% in both arms. Actuarial curves at 5 years showed that progression-free survival was 60% in the IFN/MTX group and 62% in the IFN/retinoids group (P = 0.8) that were not statistically different and overall survival (OS) rates were 70 and 67%, respectively (P = 0.03).. Both present schedules showed good tolerance and an excellent OS at 5 years, which is better than the other, more expensive and toxic, regimens. Considering the indolent course of CTCL, we suggested that those regimens, mentioned in this paper, will be regarded as the standard therapy, for patients of this setting.. The use of IFN and retinoids or low dose of cytotoxic drugs will be preferred in patients with refractory/relapse CTCL, because OS is good and toxicity is minimal.

Topics: Adult; Aged; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Drug Therapy, Combination; Female; Follow-Up Studies; Humans; Interferon alpha-2; Interferon-alpha; Lymphoma, T-Cell, Cutaneous; Male; Methotrexate; Middle Aged; Neoplasm Recurrence, Local; Recombinant Proteins; Remission Induction; Skin Neoplasms; Survival Analysis; T-Lymphocytes; Treatment Outcome; Tretinoin

Primary cutaneous T-cell lymphomas are non-Hodgkin's lymphomas with varied clinical presentation and prognosis. The most common subtypes of cutaneous T-cell lymphomas are the epidermotropic variants mycosis fungoides and Sézary syndrome. Treatment of mycosis fungoides has encompassed a variety of modalities including the use of retinoids with several studies evaluating their efficacy. The reported benefits and duration of response have varied in published data. The biological effect of retinoids is mediated by specific receptor families, retinoic acid receptor (RAR) and retinoic X receptor (RXR), with subsequently altered gene expression. There are no data available on cutaneous T-cell lymphomas that compare RAR and RXR retinoids. The objective of our retrospective, nonrandomized, single-center study was to compare the response, survival outcomes, and toxic effects in our phase II trial of the RAR-specific retinoid, all-trans retinoic acid, with clinical use of the RXR-specific retinoid, bexarotene, in patients with mycosis fungoides/Sézary syndrome who have relapsed. There was no statistical difference in response rates (12% vs 21%), response duration (20.5 vs 7.3 months), event-free survival time (4 vs 5 months), or median survival when corrected for length of follow-up. Both have favorable toxicity profiles that can be managed with medications. The toxicity profile caused by bexarotene seems to be more limited to laboratory values and better tolerated, although generally associated with more severe grades of toxicity. In conclusion, both retinoids have modest objective response rates and, therefore, most likely will have limited impact as monotherapeutic agents. However, the immunomodulatory effects of RAR and RXR retinoids provide a rational basis for using retinoids in combination with other biologic immune response modifiers, phototherapy, or cytotoxic chemotherapy.

Topics: Adult; Aged; Aged, 80 and over; Anticarcinogenic Agents; Antineoplastic Agents; Bexarotene; Female; Follow-Up Studies; Humans; Lymphoma, T-Cell, Cutaneous; Male; Middle Aged; Receptors, Retinoic Acid; Retinoid X Receptors; Retrospective Studies; Survival Analysis; Tetrahydronaphthalenes; Treatment Outcome; Tretinoin

Retinoids, natural and synthetic derivatives of vitamin A, induce cellular changes by activating nuclear retinoic acid receptors (RAR) and retinoid X receptors (RXR). Although the ability of retinoids to govern gene expression is exploited clinically for cancer therapeutics, the full benefit of retinoid-based strategies is unrealized due to detrimental side effects. Delineating the receptors that prompt cellular outcomes is critical to advancing retinoid-based approaches. Here, we identify the receptors that evoke multiple responses in cutaneous T-cell lymphoma (CTCL). The data demonstrate that RARα drives integrin β7-dependent adhesion and CCR9-mediated chemotaxis in CTCL cells. Of note, concomitant activation of RARα and RXR nuclear receptors yielded synergistic increases in adhesion and migration at concentrations where single agents were ineffective. As the established paradigm of retinoid action in CTCL is apoptosis and growth arrest, the role of RARα/RXR in these events was studied. As with adhesion and migration, RARα/RXR synergism prompted apoptosis and dampened CTCL cell proliferation. Strikingly, RARα/RXR synergism induced responses from CTCL cell lines previously reported to be unresponsive to retinoids. These data provide a novel framework that may further refine a proven CTCL therapy.

Topics: Anticarcinogenic Agents; Antineoplastic Agents; Apoptosis; Benzoates; Bexarotene; Cell Adhesion; Cell Line; Cell Movement; Cell Proliferation; Gene Expression; Humans; Integrin beta Chains; Lymphoma, T-Cell, Cutaneous; Retinoic Acid Receptor alpha; Retinoid X Receptors; RNA, Messenger; Tetrahydronaphthalenes; Tretinoin

Sulfonic acid analogues of 4-[1-(3,5,5,8,8-pentamethyl-5,6,7,8-tetrahydro-2-naphthyl)ethynyl]benzoic acid (bexarotene, 1) as well as seven novel and two reported analogues of 6-(ethyl(5,5,8,8-tetramethyl-5,6,7,8-tetrahydronaphthalen-2-yl)amino)nicotinic acid (NEt-TMN) were synthesized and assessed for selective retinoid X receptor (RXR) agonism. Compound 1 is FDA-approved for treatment of cutaneous T-cell lymphoma (CTCL); however, 1 can provoke side effects by impacting RXR-dependent receptor pathways. All of the analogues in this study were evaluated for their potential to bind RXR through modeling and then assayed in an RXR-RXR mammalian-2-hybrid (M2H) system and in RXR-responsive element (RXRE)-mediated transcriptional experiments. The EC

Topics: Antineoplastic Agents; Bexarotene; Cell Line, Tumor; Cell Proliferation; Gene Expression Regulation, Neoplastic; HEK293 Cells; Histone Deacetylase 1; Humans; Lymphoma, T-Cell, Cutaneous; Models, Molecular; Niacin; Retinoid X Receptors; Sterol Regulatory Element Binding Proteins; Tetrahydronaphthalenes

Cutaneous T-cell lymphomas (CTCL) are characterized by an infiltration of the skin with malignant T cells. Curative treatments for aggressive entities such as Sézary syndrome have not been identified yet. Arsenic trioxide (AsO3) is used for the treatment of acute promyelocytic leukemia in combination with retinoids. As the latter are established treatment options in CTCL, we sought to evaluate the efficacy of AsO3 for mono- and combination therapy in vitro. Analyses for apoptosis, cell cycle inhibition, cytotoxicity and cell viability were made after incubation of CTCL cells with AsO3 alone or in combination with the retinoids all-trans-retinoic acid or bexarotene. While AsO3 induced apoptosis, retinoids did not at the time point of analysis. However, retinoids strongly reduced cell viability. Due to the efficient apoptosis induction, AsO3 might be a potentially suitable agent for CTCL treatment, although this effect was not increased by retinoids.

Topics: Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Arsenic Trioxide; Arsenicals; Cell Line, Tumor; Cell Survival; Dose-Response Relationship, Drug; Humans; Lymphoma, T-Cell, Cutaneous; Oxides; Tretinoin

Topics: Alitretinoin; Antineoplastic Agents; Gels; Humans; Lymphoma, T-Cell, Cutaneous; Male; Middle Aged; Skin Neoplasms; Tretinoin

Retinoids are a fascinating class of compounds that exert control over cellular function from the time of conception to death. They play a critical role in such vital processes as fetal morphogenesis, cellular differentiation and apoptosis. Over the years synthetic retinoids have provided dermatologists with a spectrum of medications that have profound therapeutic effects on a variety of recalcitrant skin disorders. Moreover, retinoids are an expanding component of the treatment arsenal against hematologic and solid malignancies. Retinoids are poised to offer exciting new therapeutic options in the field of endocrinology for the treatment of diabetes and lipid disorders. Researchers and clinicians are only beginning to unveil the therapeutic potential of this class of medications. The development of new retinoid compounds targeting specific receptors promises a wealth of new therapies for the new millennium.

Topics: Acne Vulgaris; Humans; Keratosis; Leukemia, Promyelocytic, Acute; Lymphoma, T-Cell, Cutaneous; Psoriasis; Skin Neoplasms; Treatment Outcome; Tretinoin; Vitamin A

A 35-year-old man with refractory cutaneous Ki-1 lymphoma was salvaged successfully with oral 13-cis-retinoic acid (1 mg/kg/day). He had a complete remission lasting for 20 months before a single nodule recurred on his skin. Excisional biopsy of the recurrent tumor revealed a distinct morphologic change, suggesting cellular differentiation toward a more benign phenotype. No significant side effects were noted except mild xerostomia, bone pain, and hyperlipidemia. The authors believe that 13-cis-retinoic acid should be considered in the treatment of cutaneous Ki-1 lymphoma.

Topics: Adult; Antigens, Differentiation; Antigens, Neoplasm; Cell Differentiation; Humans; Immunophenotyping; Ki-1 Antigen; Lymphoma, T-Cell, Cutaneous; Male; Remission Induction; Skin Neoplasms; Tretinoin