Analysis and therapeutic targeting of the IL-1R pathway in anaplastic large cell lymphoma.

Anaplastic large cell lymphoma (ALCL), a subgroup of mature T-cell neoplasms with an aggressive clinical course, is characterized by elevated expression of CD30 and anaplastic cytology. To achieve a comprehensive understanding of the molecular characteristics of ALCL pathology and to identify therapeutic vulnerabilities, we applied genome-wide CRISPR library screenings to both anaplastic lymphoma kinase positive (ALK+) and primary cutaneous (pC) ALK- ALCLs and identified an unexpected role of the interleukin-1R (IL-1R) inflammatory pathway in supporting the viability of pC ALK- ALCL. Importantly, this pathway is activated by IL-1α in an autocrine manner, which is essential for the induction and maintenance of protumorigenic inflammatory responses in pC-ALCL cell lines and primary cases. Hyperactivation of the IL-1R pathway is promoted by the A20 loss-of-function mutation in the pC-ALCL lines we analyze and is regulated by the nonproteolytic protein ubiquitination network. Furthermore, the IL-1R pathway promotes JAK-STAT3 signaling activation in ALCLs lacking STAT3 gain-of-function mutation or ALK translocation and enhances the sensitivity of JAK inhibitors in these tumors in vitro and in vivo. Finally, the JAK2/IRAK1 dual inhibitor, pacritinib, exhibited strong activities against pC ALK- ALCL, where the IL-1R pathway is hyperactivated in the cell line and xenograft mouse model. Thus, our studies revealed critical insights into the essential roles of the IL-1R pathway in pC-ALCL and provided opportunities for developing novel therapeutic strategies.

Multimodal single-cell analysis of cutaneous T-cell lymphoma reveals distinct subclonal tissue-dependent signatures.

Cutaneous T-cell lymphoma (CTCL) is a heterogeneous group of mature T-cell neoplasms characterized by the accumulation of clonal malignant CD4+ T cells in the skin. The most common variant of CTCL, mycosis fungoides (MF ), is confined to the skin in early stages but can be accompanied by extracutaneous dissemination of malignant T cells to the blood and lymph nodes in advanced stages of disease. Sézary syndrome (SS), a leukemic form of disease, is characterized by significant blood involvement. Little is known about the transcriptional and genomic relationship between skin- and blood-residing malignant T cells in CTCL. To identify and interrogate malignant clones in matched skin and blood from patients with leukemic MF and SS, we combine T-cell receptor clonotyping with quantification of gene expression and cell surface markers at the single cell level. Our data reveal clonal evolution at a transcriptional and genetic level within the malignant populations of individual patients. We highlight highly consistent transcriptional signatures delineating skin- and blood-derived malignant T cells. Analysis of these 2 populations suggests that environmental cues, along with genetic aberrations, contribute to transcriptional profiles of malignant T cells. Our findings indicate that the skin microenvironment in CTCL promotes a transcriptional response supporting rapid malignant expansion, as opposed to the quiescent state observed in the blood, potentially influencing efficacy of therapies. These results provide insight into tissue-specific characteristics of cancerous cells and underscore the need to address the patients' individual malignant profiles at the time of therapy to eliminate all subclones.

Diagnosis of breast implant associated anaplastic large cell lymphoma by analysis of cytokines in peri-implant seromas.

More than 1300 women with breast implants have developed an anaplastic large cell lymphoma (ALCL) in fluid (seroma) around their implant. More often, seromas are due to benign causes, for example, capsule contracture, leakage, or trauma. Our report in American Journal of Hematology identified several cytokines (IL-9, IL-10, IL-13) as significantly elevated only in seromas due to ALCL. We further showed that the most robust biomarker, IL-10, could be detected by a lateral flow assay (similar to COVID detection) within minutes allowing physicians to quickly plan management, eliminate or reduce costly testing and patient time away from family. Early detection of ALCL in seromas before infiltration may avoid need for cytotoxic or immunotherapy and is possibly life-saving.

CD30 Regulation of IL-13-STAT6 Pathway in Breast Implant-Associated Anaplastic Large Cell Lymphoma.

BACKGROUND: Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is a rare, usually indolent CD30+ T-cell lymphoma with tumor cells, often surrounded by eosinophils, expressing IL-13 and pSTAT6. OBJECTIVES: The aim of this study was to understand the unique tumor pathology and growth regulation of BIA-ALCL, leading to potential targeted therapies. METHODS: We silenced CD30 and analyzed its effect on IL-13 signaling and tumor cell viability. IL-13 signaling receptors of BIA-ALCL cell lines were evaluated by flow cytometry and pSTAT6 detected by immunohistochemistry. CD30 was deleted by CRISPR/Cas9 editing. Effects of CD30 deletion on transcription of IL-13 and IL-4, and phosphorylation of STAT6 were determined by real-time polymerase chain reaction and western blotting. The effect of CD30 deletion on p38 mitogen-activated protein kinase (MAPK) phosphorylation was determined. Suppression of IL-13 transcription by a p38 MAPK inhibitor was tested. Tumor cell viability following CD30 deletion and treatment with a pSTAT6 inhibitor were measured in cytotoxicity assays. RESULTS: BIA-ALCL lines TLBR1 and TLBR2 displayed signaling receptors IL-4Rα, IL-13Rα1 and downstream pSTAT6. Deletion of CD30 by CRISPR/Cas9 editing significantly decreased transcription of IL-13, less so Th2 cytokine IL-4, and phosphorylation of STAT6. Mechanistically, we found CD30 expression is required for p38 MAPK phosphorylation and activation, and IL-13-STAT6 signaling was reduced by an inhibitor of p38 MAPK in BIA-ALCL tumor cells. Tumor cell viability was decreased by silencing of CD30, and a specific inhibitor of STAT6, indicating STAT6 inhibition is cytotoxic to BIA-ALCL tumor cells. CONCLUSIONS: These findings suggest reagents targeting the IL-13 pathway, pSTAT6 and p38 MAPK, may become useful for treating BIA-ALCL patients.

Nonmalignant CD30+ Cells in Contralateral Peri-Implant Capsule of Patient With BIA-ALCL: A Premalignant Step?

CD30 lymphocyte activation antigen and phosphorylated STAT3 (pSTAT3) are consistent markers of tumor cells in breast implant-associated anaplastic large cell lymphoma (BIA-ALCL). We present a case of BIA-ALCL in a breast implant capsule containing clustered tumor cells expressing CD30, pSTAT3, pSTAT6, interleukin 9, and granzyme B tumor cell biomarkers. Remarkably, the contralateral breast contained many scattered large, atypical CD30+ cells surrounded by inflammatory cells, raising a suspicion of bilateral BIA-ALCL, known to occur in some patients. To clarify the diagnosis, immunohistochemistry and multilabel immunofluorescence were performed. Unlike the tumor cells, the atypical CD30+ cells of the contralateral breast lacked pSTAT3, pSTAT6, interleukin 9, and granzyme B, eliminating a diagnosis of bilateral BIA-ALCL. This case highlights the importance of interpreting CD30 staining in the context of other tumor cell biomarkers and histopathology to avoid an incorrect diagnosis of BIA-ALCL. We believe the findings also suggest the possibility of CD30 expression as an early event in the multistep pathogenesis of BIA-ALCL.

IL-10, IL-13, Eotaxin and IL-10/IL-6 ratio distinguish breast implant-associated anaplastic large-cell lymphoma from all types of benign late seromas.

Breast implant-associated anaplastic large-cell lymphoma (BI-ALCL) is an uncommon peripheral T cell lymphoma usually presenting as a delayed peri-implant effusion. Chronic inflammation elicited by the implant has been implicated in its pathogenesis. Infection or implant rupture may also be responsible for late seromas. Cytomorphological examination coupled with CD30 immunostaining and eventual T-cell clonality assessment are essential for BI-ALCL diagnosis. However, some benign effusions may also contain an oligo/monoclonal expansion of CD30 + cells that can make the diagnosis challenging. Since cytokines are key mediators of inflammation, we applied a multiplexed immuno-based assay to BI-ALCL seromas and to different types of reactive seromas to look for a potential diagnostic BI-ALCL-associated cytokine profile. We found that BI-ALCL is characterized by a Th2-type cytokine milieu associated with significant high levels of IL-10, IL-13 and Eotaxin which discriminate BI-ALCL from all types of reactive seroma. Moreover, we found a cutoff of IL10/IL-6 ratio of 0.104 is associated with specificity of 100% and sensitivity of 83% in recognizing BI-ALCL effusions. This study identifies promising biomarkers for initial screening of late seromas that can facilitate early diagnosis of BI-ALCL.

Cell of Origin and Immunologic Events in the Pathogenesis of Breast Implant-Associated Anaplastic Large-Cell Lymphoma.

Breast implant-associated anaplastic large-cell lymphoma (BIA-ALCL) is a CD30-positive, anaplastic lymphoma kinase-negative T-cell lymphoma. Nearly all cases have been associated with textured implants. Most cases are of effusion-limited, indolent disease, with an excellent prognosis after implant and capsule removal. However, capsular invasion and tumor mass have a more aggressive course and a fatal outcome risk. This review summarizes the current knowledge on BIA-ALCL cell of origin and immunologic factors underlying its pathogenesis. Cytokine expression profiling of BIA-ALCL cell lines and clinical specimens reveals a predominantly type 17 helper T-cell (Th17)/Th1 signature, implicating this as its cell of origin. However, a Th2 allergic inflammatory response is suggested by the presence of IL-13, with infiltration of eosinophils and IgE-coated mast cells in clinical specimens of BIA-ALCL. The microenvironment-induced T-cell plasticity, a factor increasingly appreciated, may partially explain these divergent results. Mutations resulting in constitutive Janus kinase (JAK)-STAT activation have been detected and associated with BIA-ALCL pathogenesis in a small number of cases. One possible scenario is that an inflammatory microenvironment stimulates an immune response, followed by polyclonal expansion of Th17/Th1 cell subsets with release of inflammatory cytokines and chemokines and accumulation of seroma. JAK-STAT3 gain-of-function mutations within this pathway and others may subsequently lead to monoclonal T-cell proliferation and clinical BIA-ALCL. Current research suggests that therapies targeting JAK proteins warrant investigation in BIA-ALCL.

A novel model of controlling PD-L1 expression in ALK+ anaplastic large cell lymphoma revealed by CRISPR screening.

The success of programmed cell death protein 1 (PD-1)/PD-L1-based immunotherapy highlights the critical role played by PD-L1 in cancer progression and reveals an urgent need to develop new approaches to attenuate PD-L1 function by gaining insight into how its expression is controlled. Anaplastic lymphoma kinase (ALK)-positive anaplastic large-cell lymphoma (ALK+ ALCL) expresses a high level of PD-L1 as a result of the constitutive activation of multiple oncogenic signaling pathways downstream of ALK activity, making it an excellent model in which to define the signaling processes responsible for PD-L1 upregulation in tumor cells. Here, using clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 library screening, we sought a comprehensive understanding of the molecular effectors required for PD-L1 regulation in ALK+ ALCL. Indeed, we determined that PD-L1 induction is dependent on the nucleophosmin-ALK oncoprotein activation of STAT3, as well as a signalosome containing GRB2/SOS1, which activates the MEK-ERK and PI3K-AKT signaling pathways. These signaling networks, through STAT3 and the GRB2/SOS1, ultimately induce PD-L1 expression through the action of transcription factors IRF4 and BATF3 on the enhancer region of the PD-L1 gene. IRF4 and BATF3 are essential for PD-L1 upregulation, and IRF4 expression is correlated with PD-L1 levels in primary ALK+ ALCL tissues. Targeting this oncogenic signaling pathway in ALK+ ALCL largely inhibited the ability of PD-L1-mediated tumor immune escape when cocultured with PD-1-positive T cells and natural killer cells. Thus, our identification of this previously unrecognized regulatory hub not only accelerates our understanding of the molecular circuitry that drives tumor immune escape but also provides novel opportunities to improve immunotherapeutic intervention strategies.

Recurrent MSC E116K mutations in ALK-negative anaplastic large cell lymphoma.

Anaplastic large cell lymphomas (ALCLs) represent a relatively common group of T-cell non-Hodgkin lymphomas (T-NHLs) that are unified by similar pathologic features but demonstrate marked genetic heterogeneity. ALCLs are broadly classified as being anaplastic lymphoma kinase (ALK)+ or ALK-, based on the presence or absence of ALK rearrangements. Exome sequencing of 62 T-NHLs identified a previously unreported recurrent mutation in the musculin gene, MSC E116K, exclusively in ALK- ALCLs. Additional sequencing for a total of 238 T-NHLs confirmed the specificity of MSC E116K for ALK- ALCL and further demonstrated that 14 of 15 mutated cases (93%) had coexisting DUSP22 rearrangements. Musculin is a basic helix-loop-helix (bHLH) transcription factor that heterodimerizes with other bHLH proteins to regulate lymphocyte development. The E116K mutation localized to the DNA binding domain of musculin and permitted formation of musculin-bHLH heterodimers but prevented their binding to authentic target sequence. Functional analysis showed MSCE116K acted in a dominant-negative fashion, reversing wild-type musculin-induced repression of MYC and cell cycle inhibition. Chromatin immunoprecipitation-sequencing and transcriptome analysis identified the cell cycle regulatory gene E2F2 as a direct transcriptional target of musculin. MSCE116K reversed E2F2-induced cell cycle arrest and promoted expression of the CD30-IRF4-MYC axis, whereas its expression was reciprocally induced by binding of IRF4 to the MSC promoter. Finally, ALCL cells expressing MSC E116K were preferentially targeted by the BET inhibitor JQ1. These findings identify a novel recurrent MSC mutation as a key driver of the CD30-IRF4-MYC axis and cell cycle progression in a unique subset of ALCLs.

Granzyme B Is a Biomarker for Suspicion of Malignant Seromas Around Breast Implants.

BACKGROUND: Granzyme B (GrB) is a serine protease secreted, along with pore-forming perforin, by cytotoxic lymphocytes to mediate apoptosis in target cells. GrB has been detected in tumor cells associated with systemic and breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) but its potential use for detection of early BIA-ALCL has not been fully investigated. OBJECTIVES: Prompted by the increased incidence of BIA-ALCL, the aim of this study was to assess GrB as a new biomarker to detect early disease in malignant seromas and to better understand the nature of the neoplastic cell. METHODS: A Human XL Cytokine Discovery Magnetic Luminex 45-plex Fixed Panel Performance Assay was used to compare cytokine levels in cell culture supernatants of BIA-ALCL and other T-cell lymphomas, as well as malignant and benign seromas surrounding breast implants. Immunohistochemistry was employed to localize GrB to cells in seromas and capsular infiltrates. RESULTS: Differences in GrB concentrations between malignant and benign seromas were significant (P < 0.001). GrB was found in and around apoptotic tumor cells, suggesting that the protease may be involved in tumor cell death. CONCLUSIONS: GrB is a useful marker for early detection of malignant seromas and to identify tumor cells in seromas and capsular infiltrates. Because there is an overlap between the lowest concentrations of soluble GrB in malignant seromas and the highest concentrations of GrB in benign seromas, it is recommended that GrB be used only as part of a panel of biomarkers for the screening and early detection of BIA-ALCL.

Cytokine receptor signaling is required for the survival of ALK- anaplastic large cell lymphoma, even in the presence of JAK1/STAT3 mutations.

Activating Janus kinase (JAK) and signal transducer and activator of transcription (STAT) mutations have been discovered in many T-cell malignancies, including anaplastic lymphoma kinase (ALK)- anaplastic large cell lymphomas (ALCLs). However, such mutations occur in a minority of patients. To investigate the clinical application of targeting JAK for ALK- ALCL, we treated ALK- cell lines of various histological origins with JAK inhibitors. Interestingly, most exogenous cytokine-independent cell lines responded to JAK inhibition regardless of JAK mutation status. JAK inhibitor sensitivity correlated with the STAT3 phosphorylation status of tumor cells. Using retroviral shRNA knockdown, we have demonstrated that these JAK inhibitor-sensitive cells are dependent on both JAK1 and STAT3 for survival. JAK1 and STAT3 gain-of-function mutations were found in some, but not all, JAK inhibitor-sensitive cells. Moreover, the mutations alone cannot explain the JAK1/STAT3 dependency, given that wild-type JAK1 or STAT3 was sufficient to promote cell survival in the cells that had either JAK1or STAT3 mutations. To investigate whether other mechanisms were involved, we knocked down upstream receptors GP130 or IL-2Rγ. Knockdown of GP130 or IL-2Rγ induced cell death in selected JAK inhibitor-sensitive cells. High expression levels of cytokines, including IL-6, were demonstrated in cell lines as well as in primary ALK- ALCL tumors. Finally, ruxolitinib, a JAK1/2 inhibitor, was effective in vivo in a xenograft ALK- ALCL model. Our data suggest that cytokine receptor signaling is required for tumor cell survival in diverse forms of ALK- ALCL, even in the presence of JAK1/STAT3 mutations. Therefore, JAK inhibitor therapy might benefit patients with ALK- ALCL who are phosphorylated STAT3^.

Comparative Analysis of Cytokines of Tumor Cell Lines, Malignant and Benign Effusions Around Breast Implants.

BACKGROUND: More than 700 women have developed an anaplastic large T cell lymphoma (ALCL) surrounding textured surface breast implants, termed breast implant-associated ALCL (BIA-ALCL). Most patients with BIA-ALCL present with an accumulation of fluid (delayed seroma) around the implant. However, benign seromas without malignant cells complicating scar contracture, implant rupture, trauma, infection, and other causes are more common. For proper patient management and to avoid unnecessary surgery, a simple diagnostic test to identify malignant seromas is desirable. OBJECTIVES: The aim of this study was to develop an ancillary test for the diagnosis of malignant seromas and to gain insight into the nature of the malignant cells and their microenvironment. METHODS: We employed an immunologic assay on only 50 µL of aspirated seroma fluid. The assay measures 13 cytokines simultaneously by flow cytometry. To establish a baseline for clinical studies we measured cytokines secreted by BIA-ALCL and cutaneous ALCL lines. RESULTS: Our study of cell line culture supernatants, and 8 malignant compared with 9 benign seromas indicates that interleukin 9 (IL-9), IL-10, IL-13, IL-22, and/or interferon γ concentrations >1000 pg/mL distinguish malignant seromas from benign seromas. IL-6, known to be a driver of malignant cells, is also elevated in benign seromas and does not distinguish them from malignant seromas. CONCLUSIONS: The cytokine assay introduced in this study can be used together with levels of soluble CD30 to identify malignant seromas. Validation of these findings in a larger prospective patient cohort is warranted. The unique pattern of cytokine expression in malignant effusions surrounding breast implants gives further insight into the pathogenesis and cells of origin of BIA-ALCL.Level of Evidence: 5.

Validation of a CD30 Enzyme-Linked Immunosorbant Assay for the Rapid Detection of Breast Implant-Associated Anaplastic Large Cell Lymphoma.

BACKGROUND: Breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) is an uncommon type of non-Hodgkin lymphoma occurring in the fluid or capsule adjacent to textured breast implants. Diagnosis of BIA-ALCL of symptomatic patients requires demonstration of large anaplastic cells with uniform expression of CD30 protein on immunohistochemistry. OBJECTIVES: The authors investigated a novel, rapid, office-based, and economic in-situ enzyme-linked immunosorbent assay (ELISA) for screening BIA-ALCL patients. METHODS: A commercially available in-situ ELISA was standardized and validated for patients with confirmed BIA-ALCL diagnosis with clinical isolates. A panel of 9 pathologically confirmed BIA-ALCL patients was screened by serum, plasma, and periprosthetic effusion specimens and compared against serum, plasma, and nonneoplastic delayed seromas in 7 control patients. Statistical analysis demonstrated assay consistency and reliability. RESULTS: All BIA-ALCL effusions demonstrated CD30 ELISA detection at full and all serial concentrations. BIA-ALCL serum specimens and all control specimens were negative at full concentration and serial dilutions (1:100, 1:250, 1:500, and 1:1000). BIA-ALCL plasma specimens were weakly positive at full concentration and revealed no activity with serial dilution. CONCLUSIONS: This is the first study to demonstrate a viable alternative to CD30 immunohistochemistry for the screening of BIA-ALCL. Our study demonstrates 100% sensitivity in seroma fluid with no detectable CD30 in benign seroma samples. A CD30 ELISA represents a novel, low-cost screening test, which may be used to screen suspicious aspirations of delayed periprosthetic fluid collections in an office-based setting.

A histo-immunopathologic and prognostic study of erythrodermic cutaneous T-cell lymphoma.

BACKGROUND: Sézary syndrome (SS) and erythrodermic mycosis fungoides (E-MF) represent two expressions of erythrodermic cutaneous T-cell lymphoma (E-CTCL). METHODS: Histopathologic features were compared on skin specimens from 41 patients with SS and 70 patients with E-MF. Immunopathologic findings were compared on 42 SS and 79 E-MF specimens. RESULTS: Specimens of SS usually showed band-like dermal infiltrates with intermediate-sized lymphoid cells and few plasma cells; on the other hand E-MF more often had a perivascular infiltrative pattern, predominance of small/mixed lymphoid cells and eosinophils. SS also had lower numbers of CD8+ cells and higher numbers of CD62L+ cells compared to E-MF. For E-MF patients, the presence of large Pautrier collections, infiltrates with intermediate-sized cells, increased number of mitotic figures and ≥50% CD62L+ cells in the dermal infiltrate correlated with a relatively poor disease-specific survival. However, only the presence of mitotic figures retained prognostic significance with clinical stage as a covariate. CONCLUSIONS: Clinical stage provides the most important prognostic information for patients with E-CTCL. However, mitotic activity for E-MF and CD8+ cells <20% for SS have additional value. We hypothesize that observed differences in plasma cell and eosinophil numbers may reflect the influence of CD62L+ central memory T-cells in the microenvironment.

What Cytokines Can Tell Us About the Pathogenesis of Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL).

Cytokines, their receptors, and downstream signaling partners, especially JAK1/2 and STAT3, are key biomarkers in lymphoproliferative disorders including systemic anaplastic large cell lymphoma (ALCL). Here we review their role in breast implant-associated anaplastic large cell lymphoma (BIA-ALCL). Early results suggest that, in addition to CD30, IL-9, IL-10, and IL-13 can distinguish malignant from benign seromas. IL-6 is increased in both benign and malignant seromas. IFNγ may identify a subset of BIA-ALCL with a different clinical course. Immunohistochemical detection of nuclear transcription factors-which regulate cytokine signaling-and phosphorylated janus kinases/signal transducers and activators of transcription can inform the identification and malignant potential of CD30+ cells. The innate immune response is the first line of defense against microbes suspected to initiate BIA-ALCL. Innate lymphoid cells are grouped according to the cytokines they produce and could potentially be identified as precursors to BIA-ALCL. Cytokines modulate the tumor microenvironment and hence the pathology of BIA-ALCL such as the influx of eosinophils and capsular fibrosis mediated by IL-13. The plasticity of T cells and innate immune cells theoretically can enable therapeutic manipulations toward a less aggressive phenotype. Cytokine receptors targeted in clinical trials of inflammatory and autoimmune disorders could afford opportunities for immunotherapy of BIA-ALCL.

CD30 Induces Heat Shock Protein 90 and Signal Integration in Classic Hodgkin Lymphoma Cells.

Previous studies report deregulation of multiple signaling pathways in classic Hodgkin lymphoma (cHL) cells. However, the mechanisms of how these pathways are integrated are not fully understood. Herein, we show involvement of cHL hallmark antigen CD30 in this process. CD30 facilitates phosphorylation of heat shock factor 1, activates heat shock promoter element, and induces heat shock protein (HSP) 90. CD30 repression and subsequent inhibition of HSP90 suppresses NF-κB, extracellular signal-regulated kinase, AKT, and STAT pathways in cHL cell lines. Thus, CD30-mediated induction of HSP90 appears to serve as a central hub for integration of intracellular signaling in cHL cells. We also show that CD30 induces HSP90 through phosphorylation of heat shock factor 1 via c-Jun N-terminal kinase in cHL cells. Although anaplastic large-cell lymphoma (ALCL) also is associated with CD30 overexpression, our experiments reveal that HSP90 induction in ALCL-bearing nucleophosmin-anaplastic lymphoma kinase (ALK) does not depend on CD30 but instead on ALK via c-Jun N-terminal kinase. Together, these results highlight a novel role for CD30 in mediating integration of signaling pathways of cHL cells while being replaced in this function by ALK in ALCL cells.

Chimeric antigen receptor modified T cells that target chemokine receptor CCR4 as a therapeutic modality for T-cell malignancies.

With the emerging success of treating CD19 expressing B cell malignancies with ex vivo modified, autologous T cells that express CD19-directed chimeric antigen receptors (CAR), there is intense interest in expanding this evolving technology to develop effective modalities to treat other malignancies including solid tumors. Exploiting this approach to develop a therapeutic modality for T cell malignancies for which the available regimens are neither curative, nor confer long term survival we generated a lentivirus-based CAR gene transfer system to target the chemokine receptor CCR4 that is over-expressed in a spectrum of T cell malignancies as well as in CD4+ CD25+ Foxp3+ T regulatory cells that accumulate in the tumor microenvironment constituting a barrier against anti-tumor immunity. Ex vivo modified, donor-derived T cells that expressed CCR4 directed CAR displayed antigen-dependent potent cytotoxicity against patient-derived cell lines representing ATL, CTCL, ALCL and a subset of HDL. Furthermore, these CAR T cells also eradicated leukemia in a mouse xenograft model of ATL illustrating the potential utility of this modality in the treatment of a wide spectrum of T cell malignancies.

Primary cutaneous anaplastic large cell lymphoma with intralymphatic involvement associated with chronic lymphedema.

Chronic lymphedema predisposes to develop malignant cutaneous tumors, including angiosarcoma, Kaposi's sarcoma and B-cell lymphoma. T-cell malignancy has rarely been associated with chronic lymph stasis. Here, we report a case of primary cutaneous anaplastic large cell lymphoma (pcALCL) with lymphatic spread associated with chronic lymphedema. The patient is a 56-year-old man who received orchiectomy and right inguinal lymphadenectomy for malignant seminoma 10 years ago, which led to prominent lymphedema of the right leg. He developed extensive skin nodules on the lymphedematous area for 3 months. Histopathology findings confirmed a diagnosis of pcALCL, which is a subtype of cutaneous T-cell lymphoma characterized by the presence of CD30+ T cells. Intralymphatic infiltration of malignant cells is prominent. The pathogenesis of intralymphatic cutaneous anaplastic large cell lymphoma is largely unknown. Our case suggests that chronic lymphedema resulted in persistent CD4+ T-cell inflammation, which then may contribute to the development of pcALCL.

CD30+ T Cells in Late Seroma May Not Be Diagnostic of Breast Implant-Associated Anaplastic Large Cell Lymphoma.

The objective was to analyze and discuss the implications of a nonmalignant CD30+ late seroma. Methods included collection of seroma fluid and peripheral blood from a patient with a late seroma 22 years after initial breast reconstruction. A panel of 24 monoclonal antibodies was used to detect T-cell receptor Vß regions present on ~70% of normal human peripheral blood T lymphocytes. Flow cytometry gated on CD3+ and CD30+ activated T lymphocytes. Cytospins were used to inspect the morphology of the T lymphocytes. Results from the seroma fluid cytology revealed a spectrum of activated T lymphocytes as seen in the blood of patients with immune disorders such as infectious mononucleosis. Cells were judged to be nonmalignant by routine pathology. Flow cytometry revealed >23% of CD3+ T lymphocytes belonged to an expanded T-cell family expressing TCRVß13.2. Most Vß13.2 cells expressed T-cell activation antigen CD30 indicating that CD30 is not restricted to anaplastic large cell lymphoma (ALCL) in seroma fluids. A smaller expanded population of CD30+ T lymphocytes expressing TCRVß 13.2 was detected in the blood. In conclusion, in this index case, an expanded population of CD30+ activated T lymphocytes was detected in seroma fluid surrounding a textured breast implant as well as in peripheral blood, consistent with a local and systemic immune response. The demonstration of an expanded CD30+ T-cell population in a polyclonal background suggests a possible role for bacterial superantigens as a pathogenic factor. These data further suggest that breast implant-associated anaplastic large cell lymphoma (BIA-ALCL) may be the end stage of a CD30+ T-cell lymphoproliferative disorder. LEVEL OF EVIDENCE: 5.