Immunological-based approaches for cancer therapy

The ambiguous role of obesity in oncology by promoting cancer but boosting antitumor immunotherapy

Obesity is nowadays considered a pandemic which prevalence's has been steadily increasingly in western countries. It is a dynamic, complex, and multifactorial disease which propitiates the development of several metabolic and cardiovascular diseases, as well as cancer. Excessive adipose tissue has been causally related to cancer progression and is a preventable risk factor for overall and cancer-specific survival, associated with poor prognosis in cancer patients. The onset of obesity features a state of chronic low-grade inflammation and secretion of a diversity of adipocyte-derived molecules (adipokines, cytokines, hormones), responsible for altering the metabolic, inflammatory, and immune landscape. The crosstalk between adipocytes and tumor cells fuels the tumor microenvironment with pro-inflammatory factors, promoting tissue injury, mutagenesis, invasion, and metastasis. Although classically established as a risk factor for cancer and treatment toxicity, recent evidence suggests mild obesity is related to better outcomes, with obese cancer patients showing better responses to treatment when compared to lean cancer patients. This phenomenon is termed obesity paradox and has been reported in different types and stages of cancer. The mechanisms underlying this paradoxical relationship between obesity and cancer are still not fully described but point to systemic alterations in metabolic fitness and modulation of the tumor microenvironment by obesity-associated molecules. Obesity impacts the response to cancer treatments, such as chemotherapy and immunotherapy, and has been reported as having a positive association with immune checkpoint therapy. In this review, we discuss obesity's association to inflammation and cancer, also highlighting potential physiological and biological mechanisms underlying this association, hoping to clarify the existence and impact of obesity paradox in cancer development and treatment.

Identification of a novel immune signature for optimizing prognosis and treatment prediction in colorectal cancer

BACKGROUND

Globally, colorectal cancer (CRC) is one of the most lethal malignant diseases. However, the currently approved therapeutic options for CRC failed to acquire satisfactory treatment efficacy. Tailoring therapeutic strategies for CRC individuals can provide new insights into personalized prediction approaches and thus maximize clinical benefits.

METHODS

In this study, a multi-step process was used to construct an immune-related genes (IRGs) based signature leveraging the expression profiles and clinical characteristics of CRC from the Gene Expression Omnibus (GEO) database and the Cancer Genome Atlas (TCGA) database. An integrated immunogenomic analysis was performed to determine the association between IRGs with prognostic significance and cancer genotypes in the tumor immune microenvironment (TIME). Moreover, we performed a comprehensive in silico therapeutics screening to identify agents with subclass-specific efficacy.

RESULTS

The established signature was shown to be a promising biomarker for evaluating clinical outcomes in CRC. The immune risk score as calculated by this classifier was significantly correlated with over-riding malignant phenotypes and immunophenotypes. Further analyses demonstrated that CRCs with low immune risk scores achieved better therapeutic benefits from immunotherapy, while AZD4547, Cytochalasin B and S-crizotinib might have potential therapeutic implications in the immune risk score-high CRCs.

CONCLUSIONS

Overall, this IRGs-based signature not only afforded a useful tool for determining the prognosis and evaluating the TIME features of CRCs, but also shed new light on tailoring CRCs with precise treatment.

Efficient Colorectal Cancer Gene Therapy with IL-15 mRNA Nanoformulation

Immunogene therapy is a novel method for the treatment of colorectal cancer. Cytokine IL-15 has exhibited therapeutic anticancer potential due to its immune-stimulation property. However, conventional IL-15-based cancer gene therapy studies have been performed using the plasmid DNA form, which has potential shortcomings including weak delivery efficiency and backbone effect. In this study, an IL-15 immunogene therapy study for colon cancer using in vitro transcript mRNA is described. A protamine/liposome system (CLPP) is developed to provide efficient condensation and delivery capacity for in vivo mRNA transportation. They demonstrated that the prepared CLPP system could deliver the IL-15-encoding mRNA into C26 cells with high efficacy. The secretory expressed IL-15 cytokine by the C26 cells successfully produced lymphocyte stimulation and triggered anticancer cytotoxicity upon cancer cells in vitro. Local or systemic administration of the CLPP/mIL-15 complex exhibited obvious inhibition effects on multiple C26 murine colon cancer models with inhibition rates of up to 70% in the C26 abdominal cavity metastasis tumor model, 55% in the subcutaneous model, and 69% in the pulmonary metastasis model, demonstrating high efficacy and safety. These results successfully demonstrated the high therapeutic potential of the CLPP/mIL-15 complex for colorectal cancer immunogene therapy.

Genetic switches designed for eukaryotic cells and controlled by serine integrases

Recently, new serine integrases have been identified, increasing the possibility of scaling up genomic modulation tools. Here, we describe the use of unidirectional genetic switches to evaluate the functionality of six serine integrases in different eukaryotic systems: the HEK 293T cell lineage, bovine fibroblasts and plant protoplasts. Moreover, integrase activity was also tested in human cell types of therapeutic interest: peripheral blood mononuclear cells (PBMCs), neural stem cells (NSCs) and undifferentiated embryonic stem (ES) cells. The switches were composed of plasmids designed to flip two different genetic parts driven by serine integrases. Cell-based assays were evaluated by measurement of EGFP fluorescence and by molecular analysis of attL/attR sites formation after integrase functionality. Our results demonstrate that all the integrases were capable of inverting the targeted DNA sequences, exhibiting distinct performances based on the cell type or the switchable genetic sequence. These results should support the development of tunable genetic circuits to regulate eukaryotic gene expression.

Immune signature of T follicular helper cells predicts clinical prognostic and therapeutic impact in lung squamous cell carcinoma

Lung cancer is the leading reason of cancer-related death from cancer globally for both men and women. Recently, tumor immune heterogeneity has been implicated in cancer clinical outcome. However, this prognostic significance of immune cell types in lung squamous cell carcinoma (LUSC) is unclear and should be systematically investigated. Two microarray datasets (GSE67061 and GSE2088) from the Gene Expression Omnibus (GEO) database were downloaded and then integrated to estimate the fraction of 22 immune cell types by CIBERSORT algorithm. To validate the estimation for LUSC, the data of LUSC TCGA were also assessed in order to determine specific infiltrating immune cell type closely correlated with LUSC patients' survival determined by Cox regression analyses. Immunotherapeutic and chemotherapeutic response between the LUSC patients were also evaluated. T follicular helper cells were obtained by Cox regression analysis to develop the prognostic signature. According to this immune prognostic risk score, immune signature of T follicular helper cells is an independent and specific prognostic signature for predictions of LUSC patient overall survival. Moreover, high-risk group exhibited less expression of N6-methyladenosine (m⁶A) RNA methylation regulator including ALKBH5, METTL3, HNRNPC and KIAA1429 and was much more sensitive to immunotherapy and chemotherapy. This study suggests that this immune signature is important determinants of prognosis in LUSC and may provide potential prognostic biomarker or therapeutic target for immunotherapeutic and chemotherapeutic development.

Prognostic value of immune-related genes in the tumor microenvironment of lung adenocarcinoma and lung squamous cell carcinoma

Non-small cell lung cancer (NSCLC), which consists mainly of lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC), are the leading cause of cancer deaths worldwide. In this study, we performed a comprehensive analysis of the tumor microenvironmental and genetic factors to identify prognostic biomarkers for NSCLC. We evaluated the immune and stromal scores of patients with LUAD and LUSC using data from The Cancer Genome Atlas database with the ESTIMATE algorithm. Based on these scores, the differentially expressed genes were obtained and immune-related prognostic genes were identified. Functional analysis and protein-protein interaction network further revealed the immune-related biological processes in which these genes participated. Additionally, 22 subsets of tumor-infiltrating immune cells (TIICs) in the tumor microenvironment were analyzed with the CIBERSORT algorithm. Finally, we validated these valuable genes using an independent cohort from the Gene Expression Omnibus database. The associations of the immune and stromal scores with patients’ clinical characteristics and prognosis were positive in LUAD but negative in LUSC and the correlations of TIICs with clinical characteristics were clarified. Several differentially expressed genes were identified to be potential immune-related prognostic genes. This study comprehensively analyzed the tumor microenvironment and presented immune-related prognostic biomarkers for NSCLC.

FTIR spectra signatures reveal different cellular effects of EGFR inhibitors on nonsmall cell lung cancer cells

ATP-analogue inhibitors, Gefitinib (Iressa) and Erlotinib (Tarceva) had been approved for advanced and metastatic nonsmall cell lung cancer (NSCLC) cells against tyrosine kinase domain of epidermal growth factor receptor (EGFR). Many techniques have been developed to better understand the drug mechanism which is multistep, time-consuming and expensive. Herein, we performed Fourier-transform infrared (FTIR) microscopy for evaluating the biochemical change on NSCLC (A549) cells after treatment. At levels that produced equivalent effects, Gefitinib dramatically induced cell apoptosis via impaired mitochondrial transmembrane potential. Whereas, Erlotinib had a slight effect on A549. Principal component analysis was performed to distinguish the effect of EGFR inhibitors on A549. FTIR spectra regions were divided into three regions: lipids (3000-2800 cm^-1 ), proteins (1700-1500 cm^-1 ) and carbohydrates and nuclei acids (1200-1000 cm^-1 ). Biochemical changes can be evaluated by these spectral regions. This work may be a novel concept for utilizing FTIR spectroscopy for high-throughput discriminative effects of a drug or compound and its derivatives on cells.