[Progress of Liquid Biopsy in Early Diagnosis of Lung Cancer]

Role of exosomes in non-small cell lung cancer and EGFR-mutated lung cancer

As an important mediator of information transfer between cells, exosomes play a unique role in regulating tumor growth, supporting vascular proliferation, tumor invasion, and metastasis. Exosomes are widely present in various body fluids, and therefore they can be used as a potential tool for non-invasive liquid biopsy. The present study reviews the role of exosomes in liquid biopsy, tumor microenvironment formation, and epithelial-mesenchymal transition in non-small cell lung cancer (NSCLC). By targeting epidermal growth factor receptor (EGFR) therapy as a first-line treatment for patients with NSCLC, this study also briefly describes the occurrence of EGRF+ exosomes and the role of exosomes and their contents in non-invasive detection and potential therapeutic targets in EGFR-mutated lung cancer.

Enhanced CT-Based Radiomics to Predict Micropapillary Pattern Within Lung Invasive Adenocarcinoma

Objective

We aimed to investigate whether enhanced CT-based radiomics can predict micropapillary pattern (MPP) of lung invasive adenocarcinoma (IAC) in the pre-op phase and to develop an individual diagnostic predictive model for MPP in IAC.

Methods

170 patients who underwent complete resection for pathologically confirmed lung IAC were included in our study. Of these 121 were used as a training cohort and the other 49 as a test cohort. Clinical features and enhanced CT images were collected and assessed. Quantitative CT analysis was performed based on feature types including first order, shape, gray-level co-occurrence matrix-based, gray-level size zone matrix-based, gray-level run length matrix-based, gray-level dependence matrix-based, neighboring gray tone difference matrix-based features and transform types including Log, wavelet and local binary pattern. Receiver operating characteristic (ROC) and area under the curve (AUC) were used to value the ability to identify the lung IAC with MPP using these characteristics.

Results

Using quantitative CT analysis, one thousand three hundred and seventeen radiomics features were deciphered from R (https://www.r-project.org/). Then these radiomic features were decreased to 14 features after dimension reduction using the least absolute shrinkage and selection operator (LASSO) method in R. After correlation analysis, 5 key features were obtained and used as signatures for predicting MPP within IAC. The individualized prediction model which included age, smoking, family tumor history and radiomics signature had better identification (AUC=0.739) in comparison with the model consisting only of radiomics features (AUC=0.722). DeLong test showed that the difference in AUC between the two models was statistically significant (P<0.01). Compared with the simple radiomics model, the more comprehensive individual prediction model has better prediction performance.

Conclusion

The use of radiomics approach is of great value in the diagnosis of tumors by non-invasive means. The individualized prediction model in the study, when incorporated with age, smoking and radiomics signature, had effective predictive performance of lung IAC with MPP lesions. The combination of imaging features and clinical features can provide additional diagnostic value to identify the micropapillary pattern in IAC and can affect clinical diagnosis and treatment.

Association of Exosomal miR-210 with Signaling Pathways Implicated in Lung Cancer

MicroRNA is a class of non-coding RNA involved in post-transcriptional gene regulation. Aberrant expression of miRNAs is well-documented in molecular cancer biology. Extensive research has shown that miR-210 is implicated in the progression of multiple cancers including that of the lung, bladder, colon, and renal cell carcinoma. In recent years, exosomes have been evidenced to facilitate cell–cell communication and signaling through packaging and transporting active biomolecules such as miRNAs and thereby modify the cellular microenvironment favorable for lung cancers. MiRNAs encapsulated inside the lipid bilayer of exosomes are stabilized and transmitted to target cells to exert alterations in the epigenetic landscape. The currently available literature indicates that exosomal miR-210 is involved in the regulation of various lung cancer-related signaling molecules and pathways, including STAT3, TIMP-1, KRAS/BACH2/GATA-3/RIP3, and PI3K/AKT. Here, we highlight major findings and progress on the roles of exosomal miR-210 in lung cancer.

[Advances of Exosomes Extraction and Its Mechanism in Early Diagnosis of Lung Cancer]

肺癌是世界范围内发病率和死亡率较高的恶性肿瘤之一，严重威胁着国民的生命安全与健康。肺癌的早期诊断是肺癌预防和治疗过程中的关键环节，对肺癌进行早期诊断有利于提高患者的生存率。外泌体(exosomes)与肿瘤的侵袭与转移过程密切相关，在肺癌的发生发展过程中，外泌体发挥着重要的调控作用。近年来，以外泌体为载体的生物标记物成为肺癌强有力的诊断工具。外泌体是一种由细胞分泌的由膜包裹的大小均一、直径约为30 nm-200 nm的脂质双分子层结构小囊泡。外泌体的内容物包含不同类型的核酸和蛋白质，这些核酸和蛋白质来源于其亲本细胞(包括亲本癌细胞)，具有广泛的生理功能，包括参与免疫调节、细胞间联络等。外泌体中的生物大分子物质，如单链RNA、长非编码RNA、微小RNA(microRNA, miRNA)、蛋白质以及脂类，可以为肺癌的早期临床诊断提供有价值的信息。因此，本文就外泌体的来源、结构特点、提取方法、生物学特性和在肺癌早期诊断中的作用研究进展做简要阐述。

[Clinical Application of Plasma miR-34b-3p and miR-302a-5p in the Diagnosis of Non-small Cell Lung Cancer]

BACKGROUND

MicroRNA is a kind of single-stranded non-coding RNA whose length is about 22 nucleotides and its abnormal expression is related to disease closely. This study is aiming to explore the relative expression of miR-34b-3p and miR-302a-5p in the plasma of non-small cell lung cancer (NSCLC) patients and its clinical value.

METHODS

The levels of miR-34b-3p and miR-302a-5p in plasma were detected by real-time polymerase chain reaction (RT-PCR) in 86 patients with NSCLC, 64 patients with pulmonary tuberculosis (PTB) and 39 healthy subjects. Analyze their value in diagnosing NSCLC by contrasting and combining carcino-embryonic antigen (CEA), neuron-specific enolase (NSE), and cytokeratin 19 fragments 21-1 (CYFRA21-1).

RESULTS

The levels of plasma miR-34b-3p and miR-302a-5p in NSCLC group were significantly higher than those in the PTB group and the healthy group (P<0.05). In patients with NSCLC, the levels of plasma miR-34b-3p was correlated with the diameter of tumor (P<0.01). When using one plasma marker to diagnose NSCLC, miR-302a-5p had the highest sensitivity (82.6%) and CEA had the highest specificity (81.6%). While combined two plasma markers, miR-34b-3p+miR-302a-5p had the highest sensitivity (80.2%) and miR-34b-3p+CEA had the highest specificity (81.4%). As detected multiple markers, miR-302a-5p+NSE+CYFRA21-1 had the highest sensitivity (81.4%) and miR-34b-3p+CEA+NSE had the highest specificity (90.3%). The combination of miR-34b-3p, miR-302a-5p and CEA obtained the highest area under the curve (AUC), which was 0.832. Logistic regression model indicated that miR-34b-3p was independent risk factor for NSCLC compared to control groups.

CONCLUSIONS

Plasma miR-34b-3p and miR-302a-5p could be used as biological markers for the diagnosis of NSCLC.