Extracellular Vesicles as Biomarkers and Therapeutic Targets in Cancers

Extracellular vesicles refer to exosomes, apoptotic bodies, microvesicles and large oncosomes, which are membrane bound structures secreted by cells including cancer cells. The pathological role and translational potential of extracellular vesicles (EVs) in cancers are receiving research attention recently. The cargoes of cancer-derived EVs retain the molecular properties of their sources and cancer cells actively release EVs into body fluids that are easy to access. EVs released from cancer cells not only promote cancer progression through the delivery of cancer-associated molecules but also reflect alterations in the state of cancers during therapy. They are considered promising biomarkers for therapeutic response evaluation, especially resistance to therapy and diagnostics. This chapter discusses the various roles of extracellular vesicles in cancers and their potential as therapeutic targets

Obesity May Provide Pro-ILC3 Development Inflammatory Environment in Asthmatic Children

The prevalence of obesity in children has dramatically increased in the last few decades, and obesity has also emerged as an important risk factor for asthma. Innate mechanisms have been shown to be involved in both diseases, particularly through the recently described innate lymphoid cells (ILCs), in which ILC3s have been linked to obesity both in human and in murine models. The aim of this study was to explore whether being overweight in asthmatic children was associated with elevated circulating ILC3 or elevated messenger RNA (mRNA) levels of RORC, IL-17A, and IL-22. Our results showed significantly elevated ILC3 frequencies in overweight asthmatic children compared with nonoverweight controls based on the detection of Lin+CD127+IL-23R+ cells by flow cytometry. Moreover, elevated ILC3 frequencies positively correlated with the mRNA expression of RORC which has been identified as a transcription factor of ILC3s. The relative mRNA expression level of IL-17A was also upregulated in overweight compared to nonoverweight children, as was the relative mRNA level of IL-22. However, there were no correlations between ILC3 frequencies or the expressions of RORC, IL-17A, and IL-22 and asthma severity. These results suggested that childhood obesity is an independent factor that is associated with an elevated frequency of circulating ILC3s and higher expressions of RORC, IL-22, and IL-17A

The frequency of circulating MDSCs (HLA-DR⁻/CD14⁻/CD11b⁺/CD33⁺ cells) increased in ECA patients.

<p>The frequency of MDSCs in PBMC was analyzed by flow cytometry, the patients and healthy controls used in this experiment had been matched with sex, age and number. a: Representative diagram of flow cytometry analysis for circulating MDSCs from healthy controls. b: Representative diagram of flow cytometry analysis for circulating MDSCs from ECA patients. MDSCs, myeloid-derived suppressor cells; ECA, esophageal cancer; FSC, forward scatter; FITC, fluorescein isothiocyanate; PerCP-Cy5.5, peridinin chlorophyll protein-cyanin 5.5; PE, phycoerythrin; APC, allophycocyanin.</p

Expression of CD68/CD163 in esophageal cancer tissues and adjacent tissue.

<p>*Ten high magnification views were selected to count all cells, the cell color depth and the percentage of stained cells as the judgment result basis. According to the staining color (A): 0 = no color in cytoplasm; 1 = light yellow; 2 = pale brown; 3 = brown color. According to the percentage of stained cells (B): “0” indicates the percentage of positive cells <5%; “1″ indicates the percentage of positive cells 5%–25%; “2″ indicates the percentage of positive cells 26%–50%; “3” represents the percentage of positive cells >50%. The two scores of A plus B as a final judgment result: 0∼1: “−”; 2∼3: “+”; 4∼6: “++”.</p

Plasma concentrations of cytokines in ECA patients and healthy controls.

<p>The patients and healthy controls used in this experiment had been matched with sex, age and number. Plasma concentrations of IFN-γ (a), IL-4 (b), IL-6 (c), Arg1 (d) and IL-13 (e) were determined by ELISA. Data were analyzed by the Student’s t-test. *<i>P</i><0.05, ***<i>P</i><0.001 vs. control group. NS: no significant difference, ECA: esophageal cancer, ELISA: enzyme linked immunosorbent assay, IFN: interferon, IL: interleukin, Arg1: arginase 1.</p

Correlation between cytokines and MDSCs as well as M2 macrophages in ECA patients.

<p>A: Correlation between the plasma concentration of Arg1 and the percentages of circulating MDSCs in ECA patients. Positive correlation was found between Arg1 and MDSCs (r = 0.493, <i>P</i> = 0.006). b: Correlation between the plasma concentration of Arg1 and the mRNA level of IL-4 from ECA patients. Positive correlation was found between Arg1 and IL-4 mRNA (r = 0.510, <i>P</i> = 0.009). c: Correlation between the plasma concentrations of Arg1 and IL-13 from ECA patients. Positive correlation was found between Arg1 and IL-13 (r = 0.455, <i>P</i> = 0.017). d: Correlation between the mRNA level of IL-4 and plasma level of IL-13 from ECA patients. Positive correlation was found between IL-4 and IL-13 (r = 0.484, <i>P</i> = 0.016). e: Correlation between the mRNA level of IFN-γ and plasma level of Arg1 from ECA patients. Negative correlation was found between IFN-γ and Arg1 in ECA patients (r = −0.381, <i>P</i> = 0.038). f: Correlation between the number of CD163⁺ macrophages in cancer tissues and the percentages of circulating MDSCs in PBMC from ECA patients (r = 0.410, <i>P</i> = 0.003). g: Correlation between the number of CD163⁺ macrophages in cancer tissues and the plasma concentration of IL-13 from ECA patients (r = 0.405, <i>P</i> = 0.036).</p

The mRNA level of each gene in PBMC from ECA patients and healthy controls.

<p>The mRNA levels of IFN-γ (a), T-bet (b), IL-4 (c), GATA3 (d) and IL-12 (e) were determined by real-time PCR. Data were analyzed by the Student’s t-test. *<i>P</i><0.05, ***<i>P</i><0.001 vs. control group. NS, no significant difference. ECA, esophageal cancer; PCR, polymerase chain reaction; IFN, interferon; IL, interleukin. The patients and healthy controls used in this experiment had been matched with sex, age and number.</p

Primers used in real-time PCR.

<p>IFN, Interferon; IL, Interleukin; U, Upper; L, Lower.</p

Immunohistochemical analysis of CD68 and CD163 expression in esophageal cancer and adjacent tissues.

<p>Representative immunohistochemical pictures showed the expression of CD68 in a cancer-adjacent tissue (a). and a cancer tissue (b). Representative immunohistochemical pictures showed the expression of CD163 in a cancer-adjacent tissue (c). and a cancer tissue (d). Normal esophageal squamous epithelium (haematoxylin-eosin/HE staining) (e). Squamous cell esophageal carcinoma (HE staining) (f). Analysis of the number of CD68⁺ macrophages (g). and CD163+ macrophages (h). in cancer and cancer-adjacent tissues, the results showed that most cancer tissues had larger number of CD68+ and CD163+ macrophages infiltration than that in the cancer-adjacent tissues.</p

Relation between CD163 expression in cancer tissues and MDSC% in PBMC from ECA patients.

<p>Relation between CD163 expression in cancer tissues and MDSC% in PBMC from ECA patients.</p