Effect of neoadjuvant chemotherapy on tumor immune infiltration in breast cancer patients: Systematic review and meta-analysis.

The tumor immune infiltrate has an impact on cancer control and progression, additionally a growing body of evidence has proposed the role of neoadjuvant chemotherapy in modulating the contexture of the tumor immune infiltrate. Here, we performed a systematic review to evaluate the effect of chemotherapy in the immune infiltration of breast cancer tumors. We systematically searched Pubmed/MEDLINE, EMBASE, CENTRAL, and BVS databases with a cutoff date of 11/06/2022. Studies in patients with pathological diagnosis of BC, whose first line of treatment was only NAC, were included. Only published experimental studies that measured tumor immune infiltrate before and after NAC by hematoxylin and eosin (H&E) staining, immunohistochemistry (IHQ), or transcriptome were included. Reviews, studies with animal models and in-vitro models were excluded. Studies in which BC was not the primary tumor or studies with patients who received other types of neoadjuvant therapy were also excluded. The NIH quality assessment tool for before and after studies without control was used. We included 32 articles that evaluated the proximal tumor microenvironment before and after neoadjuvant chemotherapy in 2072 patients who received NAC as first line of treatment and who were evaluated for immune infiltrate in the pre- and post-chemotherapy tumor sample. Results were divided into two major categories immune cells and in-situ expression of immune checkpoints and cytokines. Qualitative synthesis was performed with the 32 articles included, and in nine of them a quantitative analysis was achieved, resulting in six meta-analyses. Despite high heterogeneity among the articles regarding treatment received, type of tumor reported, and techniques used to evaluate immune infiltrate, we found a significant decrease of TILs and FoxP3 expression after neoadjuvant chemotherapy. The study protocol was registered in PROSPERO 2021 (Protocol ID: CRD42021243784) on 6/29/2021.

Personalized neoantigen-based cancer immunotherapy. A literature review / Inmunoterapia personalizada contra el cáncer basada en neoantígenos. Revisión de la literatura

Abstract Introduction: The progress made in cancer immunotherapy and the clinical response of patients who have undergone this type of therapy have made it the fourth pillar of cancer treatment. Objective: To briefly describe the biological rationale of personalized neoantigen-based cancer immunotherapy, the current perspectives regarding its development, and some of the clinical outcomes achieved with this therapy. Materials and methods: A literature search was performed in PubMed, Scopus and EBSCO using the following search strategy: type of articles: original experimental studies, clinical trials, and narrative and systematic reviews addressing methods to identify mutations found in tumors and cancer immunotherapy strategies based on neoantigen-based vaccines; study population: humans and animal models; publication period: January 1989 - December 2019; language: English and Spanish; search terms: "Immunotherapy", "Neoplasms", "Mutation" and "Cancer Vaccines". Results: The initial search started with 1 344 records. Once duplicates were removed (n=176), 780 studies were excluded after reading their abstract and title. The full text of 338 articles was read to confirm which met the inclusion criteria, finally including 73 studies for full analysis. All articles retrieved were published in English and were mainly conducted in the USA (43.83%) and Germany (23.65%). In the case of original studies (n=43), 20 were performed in humans only, 9 in animals only, 2 in both models, and 12 used in silico methodology. Conclusion: Personalized cancer immunotherapy with tumor neoantigen-based vaccines is strongly emerging as a new alternative to treat cancer. However, to achieve its appropriate implementation, it is necessary to use it in combination with conventional treatments, produce more knowledge that helps clarify cancer immunobiology, and reduce the costs associated with its production.

Resumen Introducción. Los avances que se han hecho en inmunoterapia contra el cáncer y la respuesta clínica de los pacientes que han recibido este tipo de terapia la han convertido en el cuarto pilar para el tratamiento del cáncer. Objetivo. Describir brevemente el fundamento biológico de la inmunoterapia personalizada contra el cáncer basada en neoantígenos, las perspectivas actuales de su desarrollo y algunos resultados clínicos de esta terapia. Materiales y métodos. Se realizó una búsqueda de la literatura en PubMed, Scopus y EBSCO utilizando la siguiente estrategia de búsqueda: tipo de artículos: estudios experimentales originales, ensayos clínicos y revisiones narrativas y sistemáticas sobre métodos de identificación de mutaciones generadas en los tumores y estrategias de inmunoterapia del cáncer con vacunas basadas en neoantígenos; población de estudio: humanos y modelos animales; periodo de publicación: enero de 1989 a julio de 2019; idioma: inglés y español; términos de búsqueda: "Immunotherapy", "Neoplasms", "Mutation" y "Cancer Vaccines". Resultados. La búsqueda inicial arrojó 1 344 registros; luego de remover duplicados (n = 176), 780 fueron excluidos después de leer su resumen y título, y se evaluó el texto completo de 338 para verificar cuáles cumplían con los criterios de inclusión, seleccionándose finalmente 73 estudios para análisis completo. Todos los artículos recuperados se publicaron en inglés, y fueron realizados principalmente en EE. A (43.83%) y Alemania (23.65%). En el caso de los estudios originales (n=43), 20 se realizaron únicamente en humanos, 9 solo en animales, 2 en ambos modelos, y 12 usaron metodología in silico. Conclusión. La inmunoterapia personalizada contra el cáncer con vacunas basadas en neoantígenos tumorales se está convirtiendo de forma contundente en una nueva alternativa para tratar el cáncer. Sin embargo, para lograr su implementación adecuada, es necesario usarla en combinación con tratamientos convencionales, generar más conocimiento que contribuya a aclarar la inmunobiología del cáncer y reducir los costos asociados con su producción.

Human immune response to SARS-CoV-2: What is known? A scoping review / Respuesta inmune humana al SARS-CoV-2: ¿Qué se conoce? Una scoping review

Monitoring literature on the broad spectrum of the human immune response to SARS-CoV-2 is important to understand the mechanisms and progression of COVID-19. The present study undertakes a scoping review of the literature on human immune response to SARS-CoV-2 to determine the characteristics of innate and adaptive responses, as well as biomarkers and cells that play a role in the development of the infection. We searched papers in MEDLINE/PUBMED and EMBASE databases published since December 1st 2019 to to April 9th 2020 from which we selected 56 for this study. We found that the immune response is characterized by high levels of acute phase reactants, neutrophilia, low levels of NKs and eosinophils, lymphopenia, cytokine storm syndrome, exhausted T cells, impaired cytotoxic response, inadequate helper response and production of specific antibodies; concluding that immune dysregulation correlates with disease severity and high mortality.

El seguimiento de la literatura sobre la respuesta inmune humana al SARS-CoV-2 es importante para comprender los mecanismos y la progresión de COVID-19. En el presente estudio se realizó un Scoping Review de la literatura sobre la respuesta inmune humana al SARS-CoV-2 para determinar las características de la respuesta inmune innata y adaptativa, así como biomarcadores y células que juegan un papel en el desarrollo de la infección. Buscamos artículos en las bases de datos MEDLINE / PUBMED y EMBASE publicados desde el 1 de diciembre de 2019 hasta el 9 de abril de 2020, de los cuales seleccionamos 56 publicaciones para este estudio. Encontramos que la respuesta inmune se caracteriza por altos niveles de reactantes de fase aguda, neutrofilia, bajos niveles de NKs y eosinófilos, linfopenia, síndrome de tormenta de citoquinas, linfocitos T agotados, respuesta citotóxica alterada, respuesta T helper inadecuada y producción de anticuerpos específicos. En conclusión, el desequilibrio inmune se correlaciona con la severidad y la mortalidad de la enfermedad.

Immunosenescence Study of T Cells: A Systematic Review.

Background: Aging is accompanied by alterations in immune response which leads to increased susceptibility to infectious diseases, cancer, autoimmunity, and inflammatory disorders. This decline in immune function is termed as immunosenescence; however, the mechanisms are not fully elucidated. Experimental approaches of adaptive immunity, particularly for T cells, have been the main focus of immunosenescence research. This systematic review evaluates and discusses T cell markers implicated in immunosenescence. Objective: To determine the best flow cytometry markers of circulating T cells associated with immunosenescence. Methods: We systematically queried PubMed, MEDLINE, EBSCO, and BVS databases for original articles focused on two age groups of healthy humans: 18-44 (young adults) and >60 (older adults) years. In accordance with the Cochrane methodology, we synthesized data through qualitative descriptions and quantitative random effects meta-analysis due to extensive heterogeneity. Results: A total of 36 studies conducted in the last 20 years were included for the qualitative analysis and four out of these studies were used to perform the meta-analysis. A significant decrease in naïve T cell subset was observed in older adults compared to young adults. Primary markers used to identify senescent cells were loss of CD28 and increased expression of CD57 and KLRG1 in terminally-differentiated memory T cell subset in older adults. Moreover, we observed an increase in proinflammatory cytokines and decrease in telomere length in old adult T cells. It was not possible to perform quantitative synthesis on cell markers, cytokines, and telomere length because of the significant variations between the groups, which is attributed to differences in protocols and unreported measurements, thus generating a high risk of bias. Conclusions: Heterogeneity among studies in terms of data report, measurement techniques and high risk of bias were major impediments for performing a robust statistical analysis that could aid the identification of eligible flow cytometry markers of immunosenescence phenotype in T cells.