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Background:Case reports suggest photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) is an effective treatment for refractory mycosis fungoides (MF). No prospective trials have examined the use of ALA-PDT in MF. Objective:We aimed to assess the efficacy of ALA-PDT in refractory MF. Methods:This was a prospective study at Mayo Clinic in Scottsdale, Arizona in patients ≥ 18 years with plaque-stage treatment-refractory MF. Monthly sessions of ALA with blue light PDT were administered for up to six months. Responses were measured by Composite Assessment of Index Lesion Severity (CAILS) and Physician Global Assessment (PGA). Ad hoc analysis with modified CAILS (mCAILS) was performed, eliminating hyperpigmentation from scoring. Results:Eleven patients (30 total lesions) were treated. Six patients completed the trial per protocol. Objective response rates were 36.4% by PGA (10.9-69.2%), 18.2% by CAILS (2.3-51.8%), and 36.4% by mCAILS (10.9-69.2%). Limitations:Five patients did not complete all six PDT cycles per protocol, possibly accounting for reduced efficacy. Conclusion:ALA-PDT with blue light irradiation was moderately effective and well tolerated in refractory plaque stage MF. Lower response rates compared to similar trials may be partially explained by utilization of strict lesional assessment criteria and other variations in methodology. Disclosures Mangold: MiRagen:Research Funding;Sun Pharma:Research Funding;Elorac:Research Funding;Kirin:Membership on an entity's Board of Directors or advisory committees;Solagenix:Research Funding. OffLabel Disclosure: Photodynamic therapy is a two-step therapy in which a drug that acts as a photosensitizer is administered to target a diseased tissue, followed by illumination with visible light to activate the drug and destroy the target tissue. PDT has been used to treat internal cancers as well as treatment of cancer and precancer of the skin.

The cell of origin and the tumor microenvironment’s role remain elusive for the most common peripheral T-cell lymphomas (PTCLs). As macrophages promote the growth and survival of malignant T cells and are abundant constituents of the tumor microenvironment, their functional polarization was examined in T-cell lymphoproliferative disorders. Cytokines that are abundant within the tumor microenvironment, particularly interleukin (IL)-10, were observed to promote alternative macrophage polarization. Macrophage polarization was signal transducer and activator of transcription 3 dependent and was impaired by the Janus kinase inhibitor ruxolitinib. In conventional T cells, the production of T helper (Th)2-associated cytokines and IL-10, both of which promote alternative macrophage polarization, is regulated by the T-cell transcription factor GATA-binding protein 3 (GATA-3). Therefore, its role in the T-cell lymphomas was examined. GATA-3 expression was observed in 45% of PTCLs, not otherwise specified (PTCL, NOS) and was associated with distinct molecular features, including the production of Th2-associated cytokines. In addition, GATA-3 expression identified a subset of PTCL, NOS with distinct clinical features, including inferior progression-free and overall survival. Collectively, these data suggest that further understanding the cell of origin and lymphocyte ontogeny among the T-cell lymphomas may improve our understanding of the tumor microenvironment’s pathogenic role in these aggressive lymphomas.

A variety of nonmalignant cells present in the tumor microenvironment promotes tumorigenesis by stimulating tumor cell growth and metastasis or suppressing host immunity. The role of such stromal cells in T-cell lymphoproliferative disorders is incompletely understood. Monocyte-derived cells (MDCs), including professional antigen-presenting cells such as dendritic cells (DCs), play a central role in T-cell biology. Here, we provide evidence that monocytes promote the survival of malignant T cells and demonstrate that MDCs are abundant within the tumor microenvironment of T cell–derived lymphomas. Malignant T cells were observed to remain viable during in vitro culture with autologous monocytes, but cell death was significantly increased after monocyte depletion. Furthermore, monocytes prevent the induction of cell death in T-cell lymphoma lines in response to either serum starvation or doxorubicin, and promote the engraftment of these cells in nonobese diabetic/severe combined immunodeficient mice. Monocytes are actively recruited to the tumor microenvironment by CCL5 (RANTES), where their differentiation into mature DCs is impaired by tumor-derived interleukin-10. Collectively, the data presented demonstrate a previously undescribed role for monocytes in T-cell lymphoproliferative disorders.

The ISCL/EORTC recommends revisions to the Mycosis Fungoides Cooperative Group classification and staging system for cutaneous T-cell lymphoma (CTCL). These revisions are made to incorporate advances related to tumor cell biology and diagnostic techniques as pertains to mycosis fungoides (MF) and Sézary syndrome (SS) since the 1979 publication of the original guidelines, to clarify certain variables that currently impede effective interinstitution and interinvestigator communication and/or the development of standardized clinical trials in MF and SS, and to provide a platform for tracking other variables of potential prognostic significance. Moreover, given the difference in prognosis and clinical characteristics of the non-MF/non-SS subtypes of cutaneous lymphoma, this revision pertains specifically to MF and SS. The evidence supporting the revisions is discussed as well as recommendations for evaluation and staging procedures based on these revisions.

Stromal elements present within the tumor microenvironment may suppress host immunity and promote the growth of malignant lymphocytes in B cell–derived non-Hodgkin lymphoma (NHL). In contrast, little is known about the microenvironment's role in T cell–derived NHL. B7-H1 (PD-L1, CD274), a member of the B7 family of costimulatory/coinhibitory ligands expressed by both malignant cells and stromal cells within the tumor microenvironment, has emerged as an important immune modulator capable of suppressing host immunity. Therefore, B7-H1 expression and function were analyzed in cutaneous and peripheral T-cell NHL. B7-H1 was expressed by tumor cells, monocytes, and monocyte-derived cells within the tumor microenvironment in T-cell NHL and was found to inhibit T-cell proliferation and promote the induction of FoxP3+ regulatory T cells. Collectively, the data presented provide the first evidence implicating B7-H1 in the suppression of host immunity in T-cell lymphoproliferative disorders and suggest that the targeting of B7-H1 may represent a novel therapeutic approach.

Background IL-10 polarized macrophages promote tumor growth and survival. The T-cell transcription factor GATA binding protein-3 (GATA3) epigenetically regulates IL10 expression. Therefore, we investigated the extent to which GATA-3 regulates IL-10 production and macrophage polarization in T-cell lymphomas. Methods Monocyte-derived macrophages were generated and polarized with T-cell lymphoma conditioned media ((TCL-CM). Immunophenotypic and functional characteristics associated with IL10-polarized macrophages were examined. GATA3-dependent cytokine production was evaluated in T-cell lymphoma lines by shRNA knockdown. Alternatively polarized macrophages and GATA3 expression were examined in a cohort of patients with peripheral T cell lymphoma, not otherwise specified (PTCL, NOS) (n=76). Comparisons among groups were evaluated using a Student's t test. Progression-free and overall survival (PFS & OS) was estimated using the Kaplan-Meier method and two-tailed log-rank test based on Cox proportional hazards model. Results To investigate the ability of T-cell lymphomas to alternatively polarize macrophages, monocytes from healthy donors were cocultured with TCL-CM. Macrophages were shown to have immunophenotypic characteristics of IL10-polarized macrophages (pSTAT3+/CD16hi/CD163hi/HLA-DR-/lo) by flow cytometry, which was abrogated by IL10, but not IL6, neutralization. TCL-CM polarized macrophages produced abundant IL-10 and were impaired in their ability to stimulate T-cell proliferation. Collectively, these results demonstrate that T-cell lymphomas promote alternative macrophage polarization in an IL-10 dependent manner, and both CD163 and pSTAT3 may aid in their identification in clinical T-cell lymphoma specimens. Therefore, CD163+/pSTAT3+ macrophages were visualized by immunofluorescence in PTCL, NOS specimens. IL-10 polarized macrophages were not identified in normal tissues, but were abundant constituents of the tumor microenvironment in 68% of the PTCL, NOS specimens examined (n=31). STAT3 phosphorylation in response to IL-10 is dependent upon the Janus kinases (JAK) JAK1 and TYK2, both of which are inhibited at nanomolar (and clinically achievable) concentrations by the “JAK2” inhibitor ruxolitinib. Therefore, we sought to determine whether ruxolitinib may prevent IL-10-induced macrophage polarization. As expected, ruxolitinib inhibited IL-10-induced STAT3 phosphorylation. More importantly, macrophages polarized in the presence of ruxolitinib lost the immunophenotype characteristics of IL-10 polarized macrophages, and were CD16-/loCD163-/loHLA-DRhi. Furthermore, IL-10 production was significantly impaired in macrophages polarized in the presence of ruxolitinib, while their ability to stimulate T-cell proliferation was significantly increased. In a separate initiative, we identified GATA3 as the key regulator of IL-10 and Th2 cytokine (IL-4, IL-13 and IL-5) expression in T-cell lymphoma lines by shRNA knockdown assays. Therefore, we examined GATA3 expression by immunohistochemistry in PTCL, NOS specimens. GATA-3 expression was observed in most of the T-cell lymphoma lines and in 47% of PTCL, NOS specimens (n=76). In the cohort of the 76 PTCL, NOS patients, the median PFS and OS observed in GATA3+ PTCL, NOS was 5 months (4-8 months, 95% CI) and 8 months (5-14 months, 95% CI), respectively. In contrast, the median PFS and OS in GATA3- PTCL, NOS was 1.3 years (0.6-1.6, 95% CI) and 1.6 years (0.7-6.9 95% CI), respectively. Conclusions Alternatively polarized macrophages are abundant in T-cell lymphomas and are generated in an IL-10- and STAT3-dependent manner. GATA-3 regulates IL-10 production in these lymphomas, and its expression identified a high-risk subset of PTCL, NOS with distinct clinicopathological features. As IL-10-dependent STAT3 phosphorylation and macrophage polarization were impaired by ruxolitinib, the JAK2 inhibitors may warrant closer scrutiny as immunomodulatory agents. Disclosures: Off Label Use: Ruxolitinib, a JAK2 inhibitor, may warrant closer scrutiny as an immunomodulatory agent in TCL therapeutics.

The tumor microenvironment in B-cell non-Hodgkin’s lymphoma (NHL) plays an important role in supporting the growth and survival of malignant lymphocytes. In contrast, the extent to which this is true in T-cell NHL is less clear. While professional monocytederived antigen-presenting cells (MDC) are required for T-cell activation and survival, a growing body of evidence demonstrates that MDC may promote the survival of malignant T cells. Immunohistochemical staining of skin biopsies from cutaneous T-cell lymphoma (CTCL) patients (n=11) demonstrated a rich infiltrate of CD68+ macrophages and CD1a+ dendritic cells (DC). As these cells are derived from CD14+ monocytes, we examined the role of monocytes in promoting survival in malignant T cells obtained from CTCL patients (n=9). Initially, peripheral blood mononuclear cells (PBMC) were either depleted of CD14+ monocytes (>85% depleted) or mock-depleted prior to being cultured. Viability of malignant CD4+CD7− T cells was determined by Annexin V/7-AAD staining. While 90.9% (S.D. +/− 0.4%) of mock-depleted malignant T cells were viable, only 73.9% (S.D. +/− 1.3%) of monocyte-depleted cells remained viable, suggesting that monocytes may promote the survival of malignant T cells. In a similar fashion, HuT-78 cells (Sézary Syndrome cell line) were cocultured with CD14+ monocytes from normal donors. Compared with HuT-78 cells alone, the presence of CD14+ monocytes resulted in a 2.7 fold increase in thymidine incorporation (n=5; S.D. +/− 0.6). This is largely due to cytokine production, as the same experiment performed with a transwell insert resulted in a 2.1 fold increase in HuT-78 thymidine incorporation (n=5; S.D. +/− 0.4). Similar results were obtained using additional Sézary Syndrome (i.e. SeAx) and Mycosis Fungoides (i.e. MyLa) cell lines. Monocytes obtained from normal donors were subsequently cultured and cell-free conditioned media was obtained 48 hours later. Media supplemented with monocyte-conditioned media (monocyte-CM) prevented the induction of apoptosis in CTCL cell lines as measured by thymidine incorporation, trypan blue exclusion and Annexin V/propidium iodide staining. This affect was monocyte-specific, as neither T-cell nor B-cell conditioned media were observed to promote survival of CTCL cell lines. Furthermore, monocyte-CM had no affect on resting or anti-CD3 activated normal T cells. We next cultured malignant T cells obtained from PBMC (n=6) or skin biopsies (n=3) from CTCL patients in the presence or absence of monocyte-CM and assessed cell viability by Annexin V staining. 32.1% (S.D. +/− 14.7%) and 60.5% (S.D. +/− 21.5%) of malignant T cells isolated from PBMC remained viable in the absence or presence of monocyte-CM, respectively; 13.0% (S.D. +/− 10.8%) of malignant T cells isolated from skin biopsies remained viable, compared with 26.5% (S.D. +/− 8.2%) of cells grown in the presence of monocyte-CM (p=.03). Given the prevalence of MDC within CTCL-involved skin and their potential role in promoting the survival of malignant T cells, one may predict that malignant T cells may recruit monocytes in a chemokinedependent fashion. Therefore, cell-free conditioned media from CTCL cell lines (HuT- 78, SeAx, MyLa) was collected and used to promote monocyte chemotaxis in a standard chemotaxis assay. Only neutralization of CCL5 (RANTES) was capable of abrogating monocyte chemotaxis, demonstrating that the production of CCL5 by malignant T cells promotes monocyte migration. Therefore, we examined serum CCL5 levels by ELISA from both normal donors (n=24) and CTCL patients (n=23) and found an approximately 3-fold elevation in serum CCL5 in CTCL patients (normal donors: mean CCL5 10.0 ng/mL; 95% CI 7.1–13.0; CTCL patients: mean 29.2 ng/mL; 95% CI 20.6–37.8; p