Knockdown of IGF2BP2 inhibits colorectal cancer cell proliferation, migration and promotes tumor immunity by down-regulating MYC expression / 细胞与分子免疫学杂志

Objective To investigate the effect of insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) on the proliferation, migration and tumor immune microenvironment of colorectal cancer cells and its possible molecular mechanism. Methods The Cancer Genome Atlas (TCGA) database was used to analyze the expression levels of IGF2BP2 and MYC in colorectal cancer and adjacent tissues. The expression of IGF2BP2 in HCT-116 and SW480 human colorectal cancer cells was silenced by RNA interference (RNAi), and the silencing effect was detected by quantitative real-time PCR. After knocking down IGF2BP2, colony formation assay, CCK-8 assay and 5-ethynyl-2'-deoxyuridine (EdU) assay were employed to detect cell colony formation and proliferation ability. TranswellTM assay was used to detect cell migration ability. Quantitative real-time PCR was used to detect the mRNA expression of IGF2BP2, MYC, tumor necrosis factor-α (TNF-α), transforming growth factor-β (TGF-β) and interleukin-10 (IL-10). The protein expression of IGF2BP2 and MYC was detected by western blot. The binding ability of IGF2BP2 and MYC in HCT-116 cells was detected by quantitative real-time PCR after RNA immunoprecipitation. Results The results of TCGA database showed that the expression of IGF2BP2 and MYC in colorectal cancer tissues was significantly higher than that in adjacent tissues, and the survival time of colorectal cancer patients with high expression of IGF2BP2 was shorter. After silencing IGF2BP2, the viability, proliferation and migration of HCT-116 and SW480 cells were decreased. The mRNA expression of MYC, TGF-β and IL-10 in IGF2BP2 knockdown group was significantly decreased, while the expression of TNF-α mRNA was increased. The expression of MYC protein and the stability of MYC mRNA were significantly decreased. RIP-qPCR results showed that IGF2BP2 could bind to MYC mRNA. Conclusion Knockdown of IGF2BP2 inhibits colorectal cancer cell proliferation, migration and promotes tumor immunity by down-regulating MYC expression.

Increased Expression of Type-I Collagen in Malignant Colorectal Lesion and Positive Correlations with Clinical Factors / Expressão aumentada do colágeno tipo I na lesão colorretal maligna e correlações positivas com fatores clínicos

Abstract Objective Type-I collagen (Col-I) is one of the main macromolecules of the extracellular matrix, and it is involved in the desmoplastic stromal reaction, an indicator of worse prognosis in cases of colorectal cancer (CRC). The purpose of the present study was to investigate Col-I expression in cases of CRC and adenoma and to correlate with the clinical data and the data regarding the lifestyle of the patients. Methods A retrospective study including 22 patients with adenoma and 15 with CRC treated at a coloproctology service. The clinical and lifestyle data were obtained through medical records, and Col-I expression was investigated by immunohistochemistry. Results Women represented most cases of adenoma (63.64%), whereas CRC was found mainly in men (73.33%) (p=0.0448). Immunoexpression of Col-I showed a basement membrane thickening in areas of lining of epithelium and around the glands in both lesions. The cases of CRC had a quite evident fibrosis process in the stroma. The quantitative analysis demonstrated a higher protein expression in CRCs compared to adenomas (p=0.0109), as well as in female patients (p=0.0214), patients aged ≥ 50 years (p=0.0400), and in those with a positive family history of colorectal disease (p=0.0292). These results suggested a remodeling of the microenvironment of the Worked developed at the Department of Morphology, Centro de Ciências da Saúde, Universidade Federal do Espírito Santo, ES, Brazil. Conclusion The immunohistochemical analysis encourages the performance of more comprehensive studies to ascertain if our results could be a tool for the diagnosis and monitoring of the patients.

Resumo Objetivo O colágeno tipo I (Col-I) é uma das principais macromoléculas da matriz extracelular, e está envolvido na reação desmoplástica estromal, um indicador de pior prognóstico em casos de câncer colorretal (CCR). O objetivo foi investigar a expressão do Col-I emcasos de CCR e adenoma, e correlacioná-la comdados clínicos e de estilo de vida dos pacientes. Metodologia Foi realizado umestudoretrospectivo com22pacientes comadenoma e 15 comCCR tratadosemumserviço de coloproctologia.Os dados dos pacientes foramobtidos dos prontuários médicos, e a expressão do Col-I foi investigada por imunohistoquímica. Resultados As mulheres representaram a maioria dos casos de adenomas (63,64%), enquanto o CCR (73,33%) (p=0,0448) foi mais comum entre os homens. A imunoexpressão de Col-I mostrou espessamento da membrana basal em áreas de revestimento do epitélio e em volta de glândulas em ambas as lesões. O CCR apresentou fibrose no estroma. As análises quantitativas demonstraram maior expressão proteica no CCR (p=0,0109), assim como em mulheres (p=0,0214), pacientes com idade ≥ 50 anos (p=0,0400), e em pacientes com histórico positivo de doença colorretal na família (p=0,0292). Estes resultados sugerem a remodelação do microambiente tumoral na carcinogênese do CCR. As correlações clínico-patológicas positivas mostram uma ligação plausível entre o perfil do paciente e os achados imunohistoquímcos, o que indica uma possível forma de estratificação dos pacientes. Conclusão As análises imunohistoquímicas estimulam a execução de estudos mais abrangentes para confirmar se nossos resultados poderão ser uma ferramenta para o diagnóstico e o monitoramento dos pacientes.

Inmunoterapia en cáncer: Perspectivas actuales, desafíos y nuevos horizontes / Immunotherapy in cancer. Current prospects, challenges and new horizons

La activación del sistema inmunológico en pacientes con cáncer ha sido un objetivo histórico en el campo de la oncología. En las últimas décadas, nuestro entendimiento de la respuesta inmunológica antitumoral ha promovido el desarrollo de novedosas estrategias terapéuticas dando como resultado un cambio de paradigma en el tratamiento del cáncer. La utilización de agentes bloqueantes de puntos de chequeo del sistema inmunológico como PD-1/PD-L1 y CTLA-4, de agonistas de moléculas co-estimuladoras como CD137 y OX-40 y la transferencia adoptiva de células T antitumorales modificadas genéticamente han generado importantes beneficios clínicos, reflejados en respuestas objetivas y durader as, en enfermos sin tratamientos convencionales disponibles. Sin embargo, un gran número de pacientes no responde a dichas terapias generando resistencia o sufriendo recaídas de la enfermedad debido a la aparición de circuitos inhibitorios o compensatorios. La combinación racional de estrategias terapéuticas permite eliminar mecanismos de resistencia, mientras que la identificación de biomarcadores predictivos facilita la selección de pacientes respondedores a dichos tratamientos. Recientes ensayos clínicos y estudios pre-clínicos permiten vislumbrar un escenario optimista con importantes desafíos en la implementación de estrategias de inmunoterapia en cáncer.

Recent under-standing of the mechanisms that control immune system homeostasis and orchestrate antitumor responses has prompted the development of novel immunotherapeutic modalities. These include antibodies that target immune checkpoints such as PD-1/PD-L1 and CTLA-4, agonistic antibodies of costimulatory molecules such as CD137 and OX-40 and the adoptive transfer of genetically-modified antitumor T cells. However, a large number of patients do not respond to these therapies and develop resistance as a result of activation of compensatory circuits. Rational combination of immunotherapeutic modalities will help overcome resistance and will increase the number of patients who will benefit from these treatments. Moreover, identification of predictive biomarkers will allow selection of patients responding to these treatments. Emerging clinical trials and pre-clinical studies have shown exciting results anticipating new horizons in the design and implementation of cancer immunotherapeutic modalities.

Immunological-based approaches for cancer therapy

The immunologic landscape of tumors has been continuously unveiled, providing a new look at the interactions between cancer cells and the immune system. Emerging tumor cells are constantly eliminated by the immune system, but some cells establish a long-term equilibrium phase leading to tumor immunoediting and, eventually, evasion. During this process, tumor cells tend to acquire more mutations. Bearing a high mutation burden leads to a greater number of neoantigens with the potential to initiate an immune response. Although many tumors evoke an immune response, tumor clearance by the immune system does not occur due to a suppressive tumor microenvironment. The mechanisms by which tumors achieve the ability to evade immunologic control vary. Understanding these differences is crucial for the improvement and application of new immune-based therapies. Much effort has been placed in developing in silico algorithms to predict tumor immunogenicity and to characterize the microenvironment via high-throughput sequencing and gene expression techniques. Each sequencing source, transcriptomics, and genomics yields a distinct level of data, helping to elucidate the tumor-based immune responses and guiding the fine-tuning of current and upcoming immune-based therapies. In this review, we explore some of the immunological concepts behind the new immunotherapies and the bioinformatic tools to study the immunological aspects of tumors, focusing on neoantigen determination and microenvironment deconvolution. We further discuss the immune-based therapies already in clinical use, those underway for future clinical application, the next steps in immunotherapy, and how the characterization of the tumor immune contexture can impact therapies aiming to promote or unleash immune-based tumor elimination.

Protagonismo del sistema inmune en el microambiente de los tumores malignos de la mama / Role of the immune system in the microenvironment of malignant tumors of breast

Los avances recientes en la comprensión de los mecanismos génicos y moleculares del cáncer de mama han revelado que el sistema inmune protagoniza los eventos responsables del desarrollo y la progresión del tumor. Las células de la respuesta inmune innata y adaptativa, así como diversos mediadores solubles liberados por ellas, pueden establecer una respuesta antitumoral protectora o, por el contrario, inducir eventos de inflamación crónica que favorezcan la promoción y progresión de esta enfermedad. Esta dualidad, se protagoniza en el microambiente del tumor, el cual puede regular la carcinogénesis en dependencia del infiltrado de células inmunes que predominen. Esta revisión, pretende resumir los conocimientos actuales de la relación sistema inmune-cáncer de mama, enfatizando en las células inmunes del microambiente del tumor y su importancia como biomarcadores de evolución clínica de la enfermedad(AU)

The recent advances in the understanding of the genetic and molecular mechanisms of breast cancer have demonstrated that immune system plays important events responsible for the development and progression of the tumor. The cells of the innate and adaptive immune system, as well as diverse soluble mediators, may establish a protective anti-tumor response or, on the contrary, to induce events of chronic inflammation that favor promotion and progression of disease. This duality occurs in the tumor microenvironment, which can regulate the carcinogenesis depending on the predominant immune cells. This revision summarizes the current knowledge of the relationship between immune system - breast cancer, emphasizing in the immune cells of the tumor microenvironment and its importance as biological markers of the clinical evolution of the disease(AU)

Immune Response and the Tumor Microenvironment: How They Communicate to Regulate Gastric Cancer

Gastric cancer is the second most common cause of cancer-related death in the world. A growing body of evidence indicates that inflammation is closely associated with the initiation, progression, and metastasis of many tumors, including those of gastric cancer. In addition, approximately 60% of the world's population is colonized by Helicobacter pylori, which accounts for more than 50% of gastric cancers. While the role of inflammation in intestinal and colonic cancers is relatively well defined, its role in stomach neoplasia is still unclear because of the limited access of pathogens to the acidic environment and the technical difficulties isolating and characterizing immune cells in the stomach, especially in animal models. In this review, we will provide recent updates addressing how inflammation is involved in gastric malignancies, and what immune characteristics regulate the pathogenesis of stomach cancer. Also, we will discuss potential therapeutics that target the immune system for the efficient treatment of gastric cancer.

Câncer e o microambiente tumoral / Cancer and the tumor microenvironment

Antes tido como um conjunto de células alteradas em proliferação, hoje o cânceré mais bem entendido como um microambiente, em que as interações entre os elementos celulares e moleculares que o compõem são determinantes na progressão tumoral. Como resultado, a compreensão do evento neoplásico ganha complexidade crescente. A dinâmica das células tumorais passa a ser avaliada como parte de um verdadeiro tecido tumoral, sujeita a condições de vascularização, de oxigenação, de pressão intersticial e de necrose tecidual, que influenciam na cinética tumoral. Estão sendo identificados novos componentes deste nicho tumoral e as suas respectivas atuações. Entre esses integrantes, encontram-se os elementos da imunidade, cuja modulação tem sido demonstrada por uma série de pesquisas aqui revisadas, tanto no sentido da vigilância imunológica, como pressão seletiva negativa, quanto nofavorecimento da progressão tumoral. Esta revisão analisará a neoplasia do ponto de vista de um microambiente tumoral, focando na participação imunológica e na cinética tumoral, expondo as principais idéias e descobertas que criaram e estão aperfeiçoando o conceito de câncer.

Formerly referred to as a group of altered cells in proliferation, today cancer is better understood as a microenvironment, in which the interactions between the cellular andmolecular elements are determinative in tumor progression. As a result, the comprehension of a neoplasic event gains increasing complexity. The dynamics of the tumor cells are nowanalyzed as part of a true tumoral tissue, subject to conditions of vascularization, oxygenation, interstitial pressure and tissue necrosis, which influence tumor kinetics. New components of this tumoral niche and their respective actions are being identified. Among these constituentsare the elements of the immune system which, as a series of experiments have shown, are involved in the aspect of immunosurveillance, as negative selective pressure, as well as inmechanisms of tumor progression. This review will analyze neoplasia as a tumor microenvironment, focusing on immunological participation and on tumor kinetics, and exposing the mainideas and discoveries that created and are improving the concept of cancer.