Chimeric antigen receptor T-cell therapy for adult B-cell acute lymphoblastic leukemia: state-of-the-(C)ART and the road ahead.

Autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy has recently been added to the armamentarium in the battle against B-cell acute lymphoblastic leukemia (B-ALL). In this review, we discuss the trials that led to US Food and Drug Administration approval of CAR T-cell therapies in patients with B-ALL. We evaluate the evolving role of allogeneic hematopoietic stem cell transplant in the CAR T-cell era and discuss lessons learned from the first steps with CAR T-cell therapy in ALL. Upcoming innovations in CAR technology, including combined and alternative targets and off-the-shelf allogeneic CAR T-cell strategies are presented. Finally, we envision the role that CAR T cells could take in the management of adult patients with B-ALL in the near future.

CAR-T cells, from principle to clinical applications.

Chimeric antigen receptors (CAR)-T cells are genetically engineered T-lymphocytes redirected with a predefined specificity to any target antigen, in a non-HLA restricted manner, therefore combining antibody-type specificity with effector T-cell function. This strategy was developed some thirty years ago, after extensive work established the key role of the immune system against cancer. The first-engineered T-cell with chimeric molecule was designed in 1993 by Israeli immunologist Zelig Eshhar. Since then, several modifications took place, including the addition of co-stimulatory domain, to further improve CAR-T cell anti-tumor potency. The first clinical application of CAR-T cell was done in Rotterdam in 2005 for metastatic renal cell carcinoma and simultaneously at the National Cancer Institute (NCI) for metastatic ovarian cancer. These pioneered studies failed to demonstrate a therapeutic benefit, but warning emerged concerning their safety of use. The real clinical success came with anti-CD19 CAR-T cells, used since 2009 by Steven Rosenberg at the NCI in a patient with refractory follicular lymphoma and in 2011 by Carl June and David Porter from the University of Pennsylvania in patients with chronic lymphocytic leukemia and B-cell acute lymphoblastic leukemia. From that time, large centers in North America have embarked in several early phase and pivotal trials that have demonstrated unprecedent response rate in heavily pretreated chemo refractory patient with B-cell malignancies. Theses clinical success have led to the approval of three anti-CD19 CAR-T cells products for the management of B-cell malignancies in the United States and in Europe as of December 2020.

Antigen-independent killer cells prepared for adoptive immunotherapy: One source, divergent protocols, diverse nomenclature.

Adoptive cell therapy (ACT) using tumor antigen-independent killer cells has been widely used in clinical trials of cancer treatment. Circumventing the need for identification of a particular tumor-associated antigen on tumor cells, the approach has opened possibilities for the extension of ACT immunotherapy to patients with a wide variety of cancer types. Namely, Natural Killer (NK), Lymphokine-activated Killer (LAK) cells and Cytokine-induced killer (CIK) cells are the most commonly used cell types in antigen-independent adoptive immunotherapy of cancer. They all originate from peripheral blood mononuclear cells and share several common features in their killing mechanisms. However, despite broad application in clinical settings, the boundaries between these cell types are not very clearly defined. The current study aims to review different aspects of these cell populations in terms of phenotypical characteristic and preparation media, to clarify how the boundaries are set.

Frontline therapy of ovarian cancer: trials and tribulations.

PURPOSE OF REVIEW: The current article reviews the advances and challenges in the fight with cancer and the hope for cure, with a focus on clinical trials, at the one time with the best outcomes; first-line therapy. RECENT FINDINGS: To date there have been four great stories that bridge inception to development of new drugs in ovarian cancer: Serendipitous insight into the role of platinum, discovery of taxanes, understanding the microenvironment and angiogenesis, and following the science in the development of Poly (ADP-Ribose) Polymerase (PARP) inhibitors. There is a fundamental difference between overall survival (OS), simply living longer; and eradicating disease, cure. The scientific underpinning of both our understanding and the recent developments encourages an optimistic view of the remaining hurdles. SUMMARY: There has been an unprecedented explosion in the number of new drugs approved for the treatment of ovarian cancer with three new classes of agent, and five new drugs receiving food and drug administration approval in the last 3 years (Fig. 2). Getting the right drug truly transforms patients' experience with the seminal event being the development of imatinib in CML. In 1980, an average patient would have lived only 3 years, and now they only live 3 years less than a full lifespan [Bower et al. (2016). J Clin Oncol 34:2851].

Adoptive immunotherapy for hematological malignancies: Current status and new insights in chimeric antigen receptor T cells.

Hematological malignancies frequently express cancer-associated antigens that are shared with normal cells. Such tumor cells elude the host immune system because several T cells targeted against self-antigens are removed during thymic development, and those that persist are eliminated by a regulatory population of T cells. Chimeric antigen receptor-modified T cells (CAR-Ts) have emerged as a novel modality for tumor immunotherapy due to their powerful efficacy against tumor cells. These cells are created by transducing genes-coding fusion proteins of tumor antigen-recognition single-chain Fv connected to the intracellular signaling domains of T cell receptors, and are classed as first-, second- and third-generation, differing on the intracellular signaling domain number of T cell receptors. CAR-T treatment has emerged as a promising approach for patients with hematological malignancies, and there are several works reporting clinical trials of the use of CAR-modified T-cells in acute lymphoblastic leukemia, chronic lymphoblastic leukemia, multiple myeloma, lymphoma, and in acute myeloid leukemia by targeting different antigens. This review reports the history of adoptive immunotherapy using CAR-Ts, the CAR-T manufacturing process, and T cell therapies in development for hematological malignancies.

Adoptive immunotherapy for cancer.

Recent clinical success has underscored the potential for immunotherapy based on the adoptive cell transfer (ACT) of engineered T lymphocytes to mediate dramatic, potent, and durable clinical responses. This success has led to the broader evaluation of engineered T-lymphocyte-based adoptive cell therapy to treat a broad range of malignancies. In this review, we summarize concepts, successes, and challenges for the broader development of this promising field, focusing principally on lessons gleaned from immunological principles and clinical thought. We present ACT in the context of integrating T-cell and tumor biology and the broader systemic immune response.

Unique human tumor antigens: immunobiology and use in clinical trials.

The individual, unique tumor Ags, which characterize each single tumor, were described 50 years ago in rodents but their molecular characterization was limited to few of them and obtained during the last 20 years. Here we summarize the evidence for the existence and the biological role of such Ags in human tumors, although such evidence was provided only during the last 10 years and by a limited number of studies, a fact leading to a misrepresentation of unique Ags in human tumor immunology. This was also due to the increasing knowledge on the shared, self-human tumor Ags, which have been extensively used as cancer vaccines. In this review, we highlight the biological and clinical importance of unique Ags and suggest how they could be used in clinical studies aimed at assessing their immunogenic and clinical potential both in active and adoptive immunotherapy of human tumors.

Bone marrow transplantation: a historical review

Bone marrow transplantation has evolved over a period of 50 years. Laboratory observations and animal studies defined the essentials of transplantation biology. The first attempts to transfer these studies to patients met with little success. The definition of the complexities of the human leukocyte antigen (HLA) system made it possible to select compatible sibling donors and more recently unrelated donors. Transplantation of stem cells form marrow, blood, or cord blood is now the treatment of choice for a variety or hematological and genetic diseases. Transplantation using less toxic preparative regimens to induced mixed chimerism makes possible and application to autoimmune diseases. Laboratory and clinical research directed toward induction of tolerance and elimination of malignant cell point the way to a wider application of hematopoietic cell transplantation in the next decade.

Bone marrow transplantation: a review.

Bone marrow transplantation has evolved over a period of 50 years. Laboratory observations and animal studies defined the essentials of transplantation biology. The first attempts to transfer these studies to patients met with little success. The definition of the complexities of the human leukocyte antigen (HLA) system made it possible to select compatible sibling donors and more recently unrelated donors. Transplantation of stem cells from marrow, blood, or cord blood is now the treatment of choice for a variety of hematological and genetic diseases. Transplantation using less toxic preparative regimens to induce mixed chimerism makes possible an application to autoimmune diseases. Laboratory and clinical research directed toward induction of tolerance and elimination of malignant cells point the way to a wider application of hematopoietic cell transplantation in the next decade.

Cytotoxic human lymphocytes: from in vitro testing (1970s) to immunotherapy (1990s).

The senior author was the recipient of a contract (1-CP3-3292) from the National Cancer Institute, USA (NCI) in the early 1970s. The aim of NCI's targeted research program was the establishment of a tumour-specific human lymphocyte-mediated cytotoxicity assay. Neither lymphocyte growth factors nor monoclonal antibodies for lymphocyte typing were available. Tumour-specific populations of lymphocytes could not be maintained but their presence in ficoll-hypaque preparations of blood buffy coats or in primary cultures of tumours was clearly recognized. Another indiscriminately cytotoxic population of lymphocytes had usually overridden the tumour-specific population. In contradistinction to the ruling doctrine of the era, indiscriminately cytotoxic lymphocytes were readily found in the blood of tumour-bearing patients and healthy individuals (the senior author's lymphocytes were shown to practice indiscriminate cytotoxicity in 1971, an observation first interpreted as "immune surveillance at work" in an individual daily exposed to patients with metastatic cancers). Instead of converting the subject matter of the contract from a tumour-specific to a non-specific cytotoxicity assay, the NCI prematurely "phased it out" (but continued the project as intramural research). Nevertheless, many functions of cytotoxic lymphocytes that had become by now well established were foreshadowed during the early 1970s with the limited support of that NCI contract and funds from other sources. Here we recount those early observations; present the outlines of adoptive immunotherapy with various autologous lymphocyte populations and in a separate report in this volume give a technical description how these lymphocyte populations are prepared in the laboratory for therapeutic reinfusions into the patient.