Abstract ALK (Anaplastic Lymphoma Kinase)-positive Anaplastic Large Cell Lymphoma (ALCL) occurs predominantly in children and young adults. Their chemotherapeutic treatment leads to a 5-year overall survival amounted to 70-80%. The tumor relapses are often very aggressive and lethal and their underlying mechanisms are unknown. Therefore, there is still a need to improve current therapy. Crizotinib is the most advanced ALK tyrosine kinase inhibitor already used in clinics for ALK-associated lung cancers. However, mechanisms of escape to crizotinib have been reported in cell lines and patients submitted to continuous crizotinib treatment. Thus, its use in frontline treatment for ALCL is hampered by the emergence of resistance. As autophagy has been proposed as a cell survival mechanism potentially involved in the acquisition of resistance to tyrosine kinase inhibitor, we investigated here whether autophagy was activated during ALCL treatment. We demonstrated in ALCL that autophagy is induced upon ALK inactivation, as a pro-survival response. We found that different ALK inhibition approaches (crizotinib or ALK-targeting siRNA) combined with autophagy inhibition (chloroquine, 3-methyladenine or ATG7-targeting siRNA) compromised cell survival and cell growth. Altogether, our results suggest that crizotinib and chloroquine (two drugs already used in clinics) co-treatment could be beneficial for ALK-positive ALCL patients. Citation Format: Géraldine MITOU, Julie FRENTZEL, Laurence LAMANT, Fabienne MEGGETTO, Estelle ESPINOS, Patrice CODOGNO, Pierre BROUSSET, Sylvie GIURIATO. Targeting autophagy potentiates the anti-tumoral action of crizotinib in ALK-positive anaplastic large cell lymphoma. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 663. doi:10.1158/1538-7445.AM2015-663
Topic: 3. Acute myeloid leukemia - Biology & Translational Research Background: The assessment of bone marrow (BM) cells is a central component for the diagnosis of AML. However, the manual assessment of BMS and counting of differentiated cells is a time-consuming method that depends on the experience and abilities of cytomorphologists and is not fully reproducible. Aims: In this study, we develop a pipeline for the automatic segmentation and classification of cells from BMS of patients with AML using Machine Learning (ML) and Computer Vision techniques. Methods: Whole BMS slides from 647 patients diagnosed with AML between 1/2017 and 12/2020 in Toulouse University Hospital were numerized using Panoramic 250 Flash II (3DHISTECH) scanner to obtain high-definition pictures in a.MRXS format, providing multiple magnification levels whose highest corresponds to 823 X (121nm/pixel). To analyze BMS images, we designed a pipeline separated into 3 steps as described below: first, we pre-selected tiles at the deepest zoom level most likely to contain exploitable cells to define areas of interest (AOI). For this purpose, we proposed a two-tier approach to filter fixed-size tiles on two zoom levels consecutively, using a combination of a pixel-wise k-means method and decision trees using textural features. Second, we extracted BM cells from the AOI. In this step, we considered two approaches: segmentation with an in-house segmentation software, which implements a genetic algorithm to find the cells, and a deep-learning-based model called Faster-RCNN, used for cell detection in the state-of-the-art. The former method only requires a low number of annotated images to train, but the training of the second one is much faster. In the third and final step, we combined the computation of radiomics features with ML methods to classify the extracted single cell images in a semi-supervised and unsupervised manner. Results: We were able to design a pipeline allowing automatic BM cell segmentation and classification, to identify between 1k and 1.5k cells from each BMS. At a lower magnification, we were also able to design a pipeline to identify megakaryocytes. We will show the entire multi-step pipeline and examples of automatically extracted and classified cells. Summary/Conclusion: Running our AI-based pipeline shows encouraging results in terms of extraction and classification of cells from BMS of AML. Our work will lead to the development of an AI tool to support cytomorphologists in the assessment of BMS from patients with AML. It will also permit the constitution of an AML bone marrow cells library Keywords: AML, Acute myeloid leukemia, Artificial intelligence
Two black African immigrants, with no history of recent travel outside France, received a diagnosis of a malignant lymphoproliferative disorder and splenomegaly, and they subsequently underwent splenectomy. A few weeks after surgery, both patients experienced an acute episode of Plasmodium falciparum malaria, so the initial diagnosis was corrected retrospectively and changed to hyperreactive malarial splenomegaly. These cases illustrate the difficulty in distinguishing hyperreactive malarial splenomegaly from malignant lymphoproliferative disorders and therefore underline the role of the spleen in the immune system's defense against malaria.
// Pauline Gravelle 1,2,3,4,5,6,10 , Barbara Burroni 7 , Sarah Péricart 1,2,3,4,5,6,10 , Cédric Rossi 2,3,4,5,6,8,10 , Christine Bezombes 2,3,4,5,6,10 , Marie Tosolini 2,3,4,5,6,10 , Diane Damotte 7,9 , Pierre Brousset 1,2,3,4,5,6,10 , Jean-Jacques Fournié 3,4,5,6,10 and Camille Laurent 1,2,3,4,5,6,10 1 Département de Pathologie, CHU Toulouse, Institut Universitaire du Cancer de Toulouse, Centre Hospitalo-Universitaire de Toulouse, Toulouse, France 2 Institut Universitaire du Cancer de Toulouse, Toulouse, France 3 Centre de Recherches en Cancérologie de Toulouse, UMR1037 INSERM-Université Toulouse III, Toulouse, France 4 Laboratoire d’Excellence TOUCAN, Toulouse, France 5 Programme Hospitalo-Universitaire en Cancérologie CAPTOR, Toulouse, France 6 Institut Carnot CALYM, Toulouse, France 7 Service de Pathologie Hôpitaux Universitaires Paris Centre, Hopital Cochin, Paris, France 8 CHU le Bocage, Hématologie Clinique, Dijon, France 9 Centre de Recherche des Cordeliers, INSERM U1138, Paris, France 10 Paul-Sabatier, ERL 5294 CNRS, Université de Toulouse, Toulouse, France Correspondence to: Camille Laurent, email: // Keywords : PD-1/PD-L1 expression; non-Hodgkin lymphoma; prognostic value Received : November 14, 2016 Accepted : March 16, 2017 Published : March 29, 2017 Abstract Immune checkpoint blockade therapeutics, notably antibodies targeting the programmed death 1 (PD-1) receptor and its PD-L1 and PD-L2 ligands, are currently revolutionizing the treatment of cancer. For a sizeable fraction of patients with melanoma, lung, kidney and several other solid cancers, monoclonal antibodies that neutralize the interactions of the PD-1/PD-L1 complex allow the reconstitution of long-lasting antitumor immunity. In hematological malignancies this novel therapeutic strategy is far less documented, although promising clinical responses have been seen in refractory and relapsed Hodgkin lymphoma patients. This review describes our current knowledge of PD-1 and PD-L1 expression, as reported by immunohistochemical staining in both non-Hodgkin lymphoma cells and their surrounding immune cells. Here, we discuss the multiple intrinsic and extrinsic mechanisms by which both T and B cell lymphomas up-regulate the PD-1/PD-L1 axis, and review current knowledge about the prognostic significance of its immunohistochemical detection. This body of literature establishes the cell surface expression of PD-1/PD-L1 as a critical determinant for the identification of non-Hodgkin lymphoma patients eligible for immune checkpoint blockade therapies.
Anaplastic large cell lymphoma (ALCL) is a mature T cell neoplasm that often expresses the CD4+ T cell surface marker. It usually harbors the t(2;5) (p23;q35) translocation, leading to the ectopic expression of NPM-ALK, a chimeric tyrosine kinase. We demonstrated that in vitro transduction of normal human CD4+ T lymphocytes with NPM-ALK results in their immortalization and malignant transformation. The tumor cells displayed morphological and immunophenotypical characteristics of primary patient–derived anaplastic large cell lymphomas. Cell growth, proliferation, and survival were strictly dependent on NPM-ALK activity and include activation of the key factors STAT3 and DNMT1 and expression of CD30 (the hallmark of anaplastic large-cell lymphoma). Implantation of NPM-ALK–transformed CD4+ T lymphocytes into immunodeficient mice resulted in the formation of tumors indistinguishable from patients' anaplastic large cell lymphomas. Integration of "Omic" data revealed that NPM-ALK–transformed CD4+ T lymphocytes and primary NPM-ALK+ ALCL biopsies share similarities with early T cell precursors. Of note, these NPM-ALK+ lymphoma cells overexpress stem cell regulators (OCT4, SOX2, and NANOG) and HIF2A, which is known to affect hematopoietic precursor differentiation and NPM-ALK+ cell growth. Altogether, for the first time our findings suggest that NPM-ALK could restore progenitor-like features in mature CD30+ peripheral CD4+ T cells, in keeping with a thymic progenitor-like pattern.
Over the last 10 years, 240 cases of hyperplasic lymphadenitis have been systematically tested in our institution for the presence of the human immunodeficiency virus (HIV). This series comprised patients between 15 and 90 years (median of age: 38.51) without a past history of HIV infection. The technical approach consisted in an immunohistochemical procedure with a monoclonal antibody against the p24-gag protein of HIV. Among the 240 cases, 105 had a true follicular hyperplasia. Overall, this survey found that 4 cases (3 males and 1 female) were positive for p24-gag without previous knowledge of HIV infection (4/240=1.66%). HIV infection was further confirmed by serologic and molecular investigations in all cases. These results were seen exclusively in those cases with prominent follicular hyperplasia (4/105=3.80%). Staining with the anti-p24 antibody was intense and restricted to the follicular dendritic cell networks. In one case, beside hyperplasic germinal centers, one could see a regressed onion bulblike structure. One important conclusion can be drawn from this study. A systematic research of HIV proteins should be performed in all lymph node biopsies with marked follicular hyperplasia, in a context of polyadenopathy, fever, and general status alteration. Besides giving an accurate diagnosis, this approach may be helpful in cases of recent infection in which anti-p24 antibodies are not yet detectable in the serum.
