Relación entre la expresión de proteínas inhibidoras de complemento y la eficacia terapéutica de anticuerpos en cáncer de mama / Relationship between the expression of complement inhibitory proteins and therapeutic efficacy of antibodies in breast cancer

Resumen Se ha propuesto a las proteínas reguladoras de complemento (mCRP) CD55, CD46 y CD59 como piezas clave en la resistencia terapéutica contra el cáncer. Las células tumorales que expresan las mCRP, además de obstaculizar la actividad terapéutica de trastuzumab, pertuzumab y sacituzumab-govitecan en cáncer de mama, pueden regular procesos biológicos que promueven la progresión tumoral. Esta revisión describe la estructura de las mCRP y analiza su expresión a partir de bases de datos transcriptómicos de pacientes con cáncer de mama; también recopila información de interacciones y señalización de las mCRP en células tumorales. Dado que estas mCRP son dianas relevantes, se describen diversas estrategias para su inhibición y regulación para incrementar la eficacia terapéutica y evitar la resistencia y progresión del cáncer.

Abstract Complement regulatory proteins (mCRPs) CD55, CD46 and CD59 have been proposed as key elements in therapeutic resistance against cancer. mCRP-expressing tumor cells, in addition to hindering trastuzumab, pertuzumab and sacituzumab-govitecan therapeutic activity in breast cancer, can regulate biological processes that promote tumor progression. This review describes the structure of mCRPs and analyzes their expression using transcriptomic databases from breast cancer patients, in addition to collecting information on mCRPs interactions and signaling in tumor cells. Given that mCRPs are relevant targets, several strategies that have been explored for their inhibition and regulation in order to increase therapeutic efficacy and prevent cancer resistance and progression are described.

Anti-PD-1 and anti-PD-l1 antibodies as immunotherapy against cancer: a structural perspective

ABSTRACT Programmed cell death protein 1 (PD-1) and its ligand, programmed death-ligand-1 (PD-L1), play key roles in the suppression of the cytotoxic activity of T cells. PD-L1 is overexpressed on various types of cancer cells, leading to immune evasion. In the past decade, therapeutic antibodies that target the PD-1/PD-L1 axis have been developed to inhibit the immune suppression triggered by these two proteins. At present, five antibodies (two anti-PD-1 and three anti-PD-L1) have received approval by regulatory agencies in the US and Europe. In this work, we aimed to review their clinical applications and adverse effects. Furthermore, using their reported crystal structures, we discuss the similarities and differences between the PD-1/PD-L1 interface and the epitopes that are recognized by the antibodies. Detailed analyses of the contact residues involved in the ligand-receptor and target-antibody interactions have shown partial overlap. Altogether, the data presented here demonstrate that: (1) in contrast to other therapeutic antibodies, anti-PD-1/PD-L1 has a wide range of clinical applications; (2) these targeted therapies are not exempt from adverse effects; and (3) the characterization of the structural domains that are recognized by the antibodies can guide the development of new PD-1- and PD-L1-blocking agents. (REV INVEST CLIN. 2021;73(1):8-16)

A reporter gene assay for determining the biological activity of therapeutic antibodies targeting TIGIT

T cell immunoglobulin and ITIM domain (TIGIT) is a novel immune checkpoint that has been considered as a target in cancer immunotherapy. Current available bioassays for measuring the biological activity of therapeutic antibodies targeting TIGIT are restricted to mechanistic investigations because donor primary T cells are highly variable. Here, we designed a reporter gene assay comprising two cell lines, namely, CHO-CD112-CD3 scFv, which stably expresses CD112 (PVRL2, nectin-2) and a membrane-bound anti-CD3 single-chain fragment variable (scFv) as the target cell, and Jurkat-NFAT-TIGIT, which stably expresses TIGIT as well as the nuclear factor of activated T-cells (NFAT) response element-controlled luciferase gene, as the effector cell. The anti-CD3 scFv situated on the target cells activates Jurkat-NFAT-TIGIT cells through binding and crosslinking CD3 molecules of the effector cell, whereas interactions between CD112 and TIGIT prevent activation. The presence of anti-TIGIT mAbs disrupts their interaction, which in turn reverses the inactivation and luciferase expression. Optimization and validation studies have demonstrated that this assay is superior in terms of specificity, accuracy, linearity, and precision. In summary, this reliable and effective reporter gene assay may potentially be utilized in lot release control, stability assays, screening, and development of novel TIGIT-targeted therapeutic antibodies.

IL-23/IL-17 axis in the pathogenesis and treatment of systemic lupus erythematosus and rheumatoid arthritis

@#Interleukin-23 (IL-23) and IL-17 are the gatekeepers of CD4+ T helper 17 (Th17) cells where IL-23 is required for the development and expansion of Th17 cells that subsequently produce IL-17 to promote inflammation. Owing to such pro-inflammatory properties, the IL-23/IL-17 axis has emerged as an important mechanism in the pathogenesis of autoimmune diseases including systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). In recent years, therapeutic antibodies targeting IL-23 (e.g. ustekinumab, tildrakizumab, guselkumab) or IL-17 (e.g. brodalumab, secukinumab, ixekizumab) have been approved for the treatment of various autoimmune diseases. In this review, we describe the pathogenic mechanisms of IL-23/IL-17 axis in SLE and RA, as well as summarising the findings from phase II and III clinical trials of anti-IL-23/IL-17 therapeutic antibodies in SLE and RA patients. In particular, phase II study has demonstrated that the anti-IL-23 antibody (ustekinumab) confers enhanced treatment outcomes in SLE patients, while anti-IL-17 antibodies (secukinumab and ixekizumab) have shown improved clinical benefits for RA patients in phase II/III studies. Our review highlights the emerging importance of targeting the IL-23/IL-17 axis in SLE and RA patients

The use of biosimilar medicines in oncology - position statement of the Brazilian Society of Clinical Oncology (SBOC)

A biosimilar is a biologic product that is similar to a reference biopharmaceutical product, the manufacturing process of which hinders the ability to identically replicate the structure of the original product, and therefore, it cannot be described as an absolute equivalent of the original medication. The currently available technology does not allow for an accurate copy of complex molecules, but it does allow the replication of similar molecules with the same activity. As biosimilars are about to be introduced in oncology practice, these must be evaluated through evidence-based medicine. This manuscript is a position paper, where the Brazilian Society of Clinical Oncology (SBOC) aims to describe pertinent issues regarding the approval and use of biosimilars in oncology. As a working group on behalf of SBOC, we discuss aspects related to definition, labeling/nomenclature, extrapolation, interchangeability, switching, automatic substitution, clinical standards on safety and efficacy, and the potential impact on financial burden in healthcare. We take a stand in favor of the introduction of biosimilars, as they offer a viable, safe, and cost-effective alternative to the biopharmaceutical products currently used in cancer. We hope this document can provide valuable information to support therapeutic decisions that maximize the clinical benefit for the thousands of cancer patients in Brazil and can contribute to expedite the introduction of this new drug class in clinical practice. We expect the conveyed information to serve as a basis for further discussion in Latin America, this being the first position paper issued by a Latin American Oncology Society.

Presente y futuro de los anticuerpos recombinantes terapéuticos / Present and future of therapeutic recombinant antibodies

Los anticuerpos constituyen un componente fundamental del sistema inmune, permitiendo el reconocimiento con alta especificidad y posterior destrucción de moléculas extrañas. Los anticuerpos monoclonales, producidos por la tecnología del hibridoma, presentan desventajas para su uso en terapia humana debido a su origen en una especie diferente. La ingeniería genética posibilitó la utilización de los anticuerpos monoclonales para terapias humanas, generando los anticuerpos recombinantes terapéuticos. Así, los anticuerpos recombinantes se han transformado en un importante grupo de fármacos; con decenas de ellos aprobados para terapia humana y cientos en desarrollo. Se utilizan con éxito como tratamiento para un amplio rango de patologías, tales como cáncer, autoinmunidad e infecciones, siendo desde hace años el biofármaco con mayores ventas. Inicialmente todos los anticuerpos recombinantes terapéuticos presentaban la estructura convencional de los anticuerpos. Sin embargo, más recientemente, se han generado nuevos diseños que no poseen las características estructurales naturales, como los anticuerpos de simple cadena y bi-específicos. Debido al desarrollo y éxito de la tecnología de anticuerpos recombinantes, se espera un aumento constante en el número de anticuerpos terapéuticos contra nuevos blancos, además de la generación de nuevas estructuras, usos y estrategias terapéuticas. En esta revisión, nos centraremos en las características estructurales y los nuevos formatos de anticuerpos, así como su aplicación clínica en el tratamiento de diversas patologías. Además analizaremos los nuevos formatos de anticuerpos que se encuentran en el mercado y la aparición de los anticuerpos biosimilares.

Antibodies are a key component of the immune system, acting in the highly specific recognition and subsequent destruction of foreign molecules. Monoclonal antibodies produced by hybridoma technology have disadvantages for use in human therapy becauseof its origin in a different species. Genetic engineering enabled the use of monoclonalantibodies for human therapies, generating recombinant therapeutic antibodies. Thus, the recombinant antibodies have become an important group of drugs; dozens of them are approved for human therapy and there are hundreds in development. They are successfully used as a treatment for a wide range of pathologies, such as cancer, autoimmunity and infections, being the biopharmaceutical with higher sales. Initially therapeutic recombinant antibodies showed the conventional structure of the antibodies. However, more recently, new designs that do not have natural structural features havebeen generated such as single chain formats and bi-specific antibodies. Due to development and success of recombinant antibody technology, a steady increase in the number of newtherapeutic drugs against new targets is expected in addition to the generation of new structures, uses and therapeutic strategies. In this review, we will focus on their structural features and clinical application in the treatment of various pathologies. We will also discuss new formats of antibodies and the emergence of biosimilar antibodies.