Expression of EGFR Is Closely Related to Reduced 3-Year Survival Rate in Chinese Female NSCLC

Machine learning-driven prediction of brain metastasis in lung adenocarcinoma using miRNA profile and target gene pathway analysis of an mRNA dataset

BACKGROUND

Brain metastasis (BM) is common in lung adenocarcinoma (LUAD) and has a poor prognosis, necessitating predictive biomarkers. MicroRNAs (MiRNAs) promote cancer cell growth, infiltration, and metastasis. However, the relationship between the miRNA expression profiles and BM occurrence in patients with LUAD remains unclear.

METHODS

We conducted an analysis to identify miRNAs in tissue samples that exhibited different expression levels between patients with and without BM. Using a machine learning approach, we confirmed whether the miRNA profile could be a predictive tool for BM. We performed pathway analysis of miRNA target genes using a matched mRNA dataset.

RESULTS

We selected 25 miRNAs that consistently exhibited differential expression between the two groups of 32 samples. The 25-miRNA profile demonstrated a strong predictive potential for BM in both Group 1 and Group 2 and the entire dataset (area under the curve [AUC] = 0.918, accuracy = 0.875 in Group 1; AUC = 0.867, accuracy = 0.781 in Group 2; and AUC = 0.908, accuracy = 0.875 in the entire group). Patients predicted to have BM, based on the 25-miRNA profile, had lower survival rates. Target gene analysis of miRNAs suggested that BM could be induced through the ErbB signaling pathway, proteoglycans in cancer, and the focal adhesion pathway. Furthermore, patients predicted to have BM based on the 25-miRNA profile exhibited higher expression of the epithelial-mesenchymal transition signature, TWIST, and vimentin than those not predicted to have BM. Specifically, there was a correlation between EGFR mRNA levels and BM.

CONCLUSIONS

This 25-miRNA profile may serve as a biomarker for predicting BM in patients with LUAD.

Nanoparticles for local delivery of siRNA in lung therapy

An overview of the application of natural and synthetic, non-viral vectors for oligonucleotide delivery into the lung is presented in this review, with a special focus on lung cancer. Due to the specificity of the respiratory tract, its structure and natural barriers, the administration of drugs (especially those based on nucleic acids) is a particular challenge. Among widely tested non-viral drug and oligonucleotides carriers, synthetic polymers seem to be most promising. Unique properties of these nanoparticles allow for essentially unlimited possibilities regarding their design and modification. This gives hope that optimal nanoparticles with ideal nucleic acid carrier properties for lung cancer therapy will eventually emanate.

Extracellular vesicle-associated microRNA-221-3p secreted by drug-resistant lung cancer cells targets HMBOX1 to promote the progression of lung cancer

Extracellular vesicles (EVs) have received increasing attention for their role as possible regulators of cancer. miR-221-3p is a microRNA (miR) up-regulated in EVs secreted by drug-resistant A549-GR lung cancer cells. However, the underlying mechanism through which miR-221-3p-containing EVs regulate the progression of lung cancer remains elusive. Here, we attempted to reveal the mechanism by which miR-221-3p-containing EVs secreted by drug-resistant lung cancer cells regulate the functions of surrounding cells during the progression of lung cancer. A gemcitabine-sensitive lung cancer cell line was treated with isolated drug-resistant lung cancer EVs followed by an evaluation of the proliferation and migration of sensitive lung cancer cell lines and their resistance to gemcitabine treatment. Moreover, the miR-221-3p target gene HMBOX1 was identified by the Targetscan database while the progression of lung cancer was detected by knocking down miR-221-3p or overexpressing HMBOX1, or by treating sensitive cell lines with Akt/mTOR activator and inhibitor, respectively. Furthermore, an in vivo study was performed to validate the relationship between miR-221-3p and HMBOX1 and their roles in the progression of lung cancer. The proliferation and migration of sensitive lung cancer cell lines and their resistance to drugs were significantly enhanced after the treatment with drug-resistant EVs. Knockdown of miR-221-3p (in the EV of drug-resistant lung cancer or overexpression of HMBOX1 in sensitive lung cancer cell lines) reduced the transformation of sensitive lung cell lines, whereas, the treatment of sensitive lung cell lines with Akt/mTOR activator or inhibitor significantly affected the progression of lung cancer. In vivo experiments further confirmed that miR-221-3p released by drug-resistant lung cancer cells targeted the HMBOX1 to regulate the Akt/mTOR signaling pathway and affected the progression of lung cancer. We conclude that miR-221-3p-containing EVs secreted by drug-resistant lung cancer cells can potentially activate the Akt/mTOR signaling pathway by inhibiting HMBOX1, promoting the progression of lung cancer. The regulation of miR-221-3p represents a novel therapeutic target for the treatment of lung cancer.

Measurement of Serum EGFR mRNA Expression is a Reliable Predictor of Treatment Response and Survival Outcomes in Non- Small Cell Lung Cancer

Background:

EGFR over-expression plays a key role in the development and progression of lung cancer. However, its status as a prognostic biomarker for survival outcomes is unclear.

Objectives:

To evaluate the prognostic utility of serum EGFR mRNA expression in Non-Small cell lung cancer (NSCLC) for treatment response and survival.

Methods:

EGFR mRNA levels were determined in serum using quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Based on ROC curve, a cut off value of 16.0-fold increase was selected to categorize patients into low EGFR (≤ 16.0) and high EGFR (> 16.0) groups.

Results:

A total of 350 subjects were included (78.3% males), with mean (± SD) age of 57.1 (± 11.2) years, and including 247 (70.6%) adenocarcinoma (ADC). Majority (73.1%) had metastatic (stage IV) disease. Patients had higher pre-treatment serum EGFR mRNA levels than controls [median fold-increase (min, max), 16.2 (1.9, 66.7). Serum EGFR mRNA levels significantly reduced in those who achieved objective response and disease control. Significantly longer OS and PFS was observed in subjects having baseline EGFR mRNA expression ≤ 16.0 fold- increase compared to those with > 16.0 fold- increase [median (95% CI) OS: 25.0 (14.9, NR) versus 7.7 (6.3, 8.9) months; HR (95% CI) 2.9 (2.3, 4.0), p< 0.001; and PFS: 9.9 (7.1, 11.5) versus 6.0 (4.1, 7.5) months; HR (95% CI) 1.8 (1.3, 2.4), p< 0.001].

Conclusion:

Serum EGFR mRNA expression is a useful parameter for predicting treatment response and survival outcomes in NSCLC.

Targeting human epidermal growth factor receptor 2 enhances radiosensitivity and reduces the metastatic potential of Lewis lung carcinoma cells

BACKGROUND

Sublethal radiation induces matrix metalloproteinase 9 (MMP-9)-mediated radioresistance in Lewis lung carcinoma (LLC) cells and their metastatic dissemination. We aim to determine if EGFR/HER2 activation associates with MMP-9-mediated radioresistance and invasiveness in irradiated LLC cells.

METHODS

LLC cells were treated with erlotinib or afatinib followed by sublethal radiation. After irradiation, we examined the phosphorylation of EGFR/HER2 and MMP-9 expression. Colony formation assay determined if the kinase inhibitors sensitize LLC cells to radiation. Matrigel-coated Boyden chamber assay assessed cellular invasiveness. Resulting tumors of wild-type LLC cells or HER2 knock-down mutant cells were irradiated to induce pulmonary metastases.

RESULTS

Afatinib more effectively sensitized LLC cells to radiation and decreased invasiveness by inhibiting phosphorylation of EGFR, HER2, Akt, ERK, and p38, and down-regulating MMP-9 when compared to erlotinib. Afatinib abolished radiation-induced lung metastases in vivo. Furthermore, LLC HER2 knock-down cells treated with radiation had growth inhibition.

CONCLUSION

Dual inhibition of radiation-activated EGFR and HER2 signaling by afatinib suppressed the proliferation and invasion of irradiated LLC cells. Increased radiosensitivity and decreased metastatic dissemination were observed by pharmacological or genetic HER2 inhibition in vivo. These findings indicate that HER2 plays a pivotal role in enhancing radioresistance and reducing metastatic potential of LLC cells.

Total flavonoids suppress lung cancer growth via the COX-2-mediated Wnt/β-catenin signaling pathway

The aim of the present study was to explore the anti-cancer effects of total flavonoids (TF) on lung cancer and to investigate the underlying mechanism. The inhibitory effect of TF on the proliferation of A549 cells in vitro was measured using an MTT assay. The apoptotic rate of TF-treated A549 cells was analyzed using flow cytometry and terminal deoxynucleotidyl transferase-mediated biotinylated UTP nick end labeling. Migration and invasion assays were performed to investigate the anti-migration effect of TF on A549 cells. Reverse-transcription quantitative PCR was used to analyze BCL2-like 2, BCL2, Bax, Bad, cyclooxygenase 2 (COX-2), Wnt and β-catenin mRNA expression levels in A549 cells. The in vivo anti-cancer effect of TF was investigated in a subcutaneous xenograft model of lung cancer in BALB/c nude mice. The results obtained in the present study revealed that TF exerted a significant inhibitory effect on the proliferation of A549 cells in a dose-dependent manner (P<0.01). TF induced apoptosis of A549 cells, which exhibited increased and decreased expression of pro- and anti- apoptotic genes, respectively. Furthermore, TF had a significant inhibitory effect on the migration and invasion of A549 cells (P<0.01). The mRNA expression levels of COX-2, Wnt and β-catenin were significantly downregulated in TF-treated A549 cells compared with controls. Additionally, treatment with TF inhibited tumor growth in mice, with a tumor inhibition rate of 64.07% compared with the controls. TF exhibited significant tumor inhibitory effects in vivo by promoting the apoptosis of tumor cells. In conclusion, the results suggested that TF may regulate lung cancer growth via the COX-2-Wnt/β-catenin signaling pathway. TF may serve as a novel anti-cancer agent for the treatment of lung cancer.

LncRNA DLX6-AS1 promotes the proliferation, invasion, and migration of non-small cell lung cancer cells by targeting the miR-27b-3p/GSPT1 axis

Background: Non-small cell lung cancer (NSCLC) has a significant impact on human health. The aim of this study was to explore the role of long non-coding RNA DLX6-AS1 in the proliferation, migration, and invasion of NSCLC cells. Methods: The expression of DLX6-AS1 in NSCLC tumor tissues and cell lines was examined by qRT-PCR. The effects of DLX6-AS1 knockdown on cell proliferation, migration, and invasion were assessed by Cell Counting Kit-8, wound healing, and transwell assays, respectively. Bioinformatics analyses, luciferase reporter assays, and RNA pull-down assays were employed to examine the mechanism by which DLX6-AS1 exerted its oncogenesis effects in NSCLC. The anti-tumor effect of silencing DLX6-AS1 in vivo was also evaluated. Results: DLX6-AS1 was over-expressed in NSCLC tumor tissues and cell lines and its level of expression was found to be associated with tumor size and advanced clinical stage in patients with NSCLC. Downregulation of DLX6-AS1 inhibited cell proliferation, cell clone formation, migration, and invasion of NSCLC cells. DLX6-AS1 was found to interact with miR-27b-3p/GSPT1. DLX6-AS1 expression was negatively correlated with miR-27b-3p expression, but positively correlated with GSPT1 expression in NSCLC samples. DLX6-AS1 knockdown also effectively suppressed tumor growth in an in vivo xenograft model. Conclusion: DLX6-AS1 regulated NSCLC progression by targeting the miR-27b-3p/GSPT1 axis, which may provide novel insights for NSCLC prognosis and therapy.

Role of cytokines in combinatorial immunotherapeutics of non-small cell lung cancer through systems perspective

Lung cancer is the leading cause of deaths related to cancer and accounts for more than a million deaths per year. Various new strategies have been developed and adapted for treatment; still the survival for 5 years is just 16% in patients with non‐small cell lung cancer (NSCLC). Most of these strategies to combat NSCLC whether it is a drug molecule or immunotherapy/vaccine candidate require a big cost and time. Integration of computational modeling with systems biology has opened new avenues for understanding complex cancer biology. Resolving the complex interactions of various pathways and their crosstalk leading to oncogenic changes could identify new therapeutic targets with lesser cost and time. Herein, this review provides an overview of various aspects of NSCLC along with available strategies for its cure concluding with our insight into how systems approach could serve as a therapeutic intervention dissecting the immunologic parameters and cross talk between various pathways involved.

Polymeric Nanoparticle-Mediated Gene Delivery for Lung Cancer Treatment

In recent years, researchers have focused on targeted gene therapy for lung cancer, using nanoparticle carriers to overcome the limitations of conventional treatment methods. The main goal of targeted gene therapy is to develop more efficient therapeutic strategies by improving the bioavailability, stability, and target specificity of gene therapeutics and to reduce off-target effects. Polymer-based nanoparticles, an alternative to lipid and inorganic nanoparticles, efficiently carry nucleic acid therapeutics and are stable in vivo. Receptor-targeted delivery is a promising approach that can limit non-specific gene delivery and can be achieved by modifying the polymer nanoparticle surface with specific receptor ligands or antibodies. This review highlights the recent developments in gene delivery using synthetic and natural polymer-based nucleic acid carriers for lung cancer treatment. Various nanoparticle systems based on polymers and polymer combinations are discussed. Further, examples of targeting ligands or moieties used in targeted, polymer-based gene delivery to lung cancer are reviewed.

Reproducibility of the EGFR immunohistochemistry scores for tumor samples from patients with advanced non-small cell lung cancer

Epidermal growth factor receptor (EGFR) is overexpressed in >60% of non-small cell lung cancer (NSCLC) cases. In combination with radiotherapy or chemotherapy, first-line treatments with antibodies against EGFR, including cetuximab and necitumumab, have demonstrated benefits by increasing overall survival (OS), particularly in patients who overexpress EGFR. The present study evaluated the interobserver agreement among three senior pathologists, who were blinded to the clinical outcomes and assessed tumor samples from 85 patients with NSCLC using the H-score method. EGFR immunohistochemistry was performed using a qualitative immunohistochemical kit. The reported (mean ± standard deviation) H-scores from each pathologist were 111±102, 127±103 and 128.53±104.03. The patients with average H-scores ≥1, ≥100, ≥200 and between 250-300 were 85.9, 54.1, 28.2 and 12.9, respectively. Patients who had an average H-score >100 had a shorter OS time compared with those with lower scores. Furthermore, patients with EGFR mutations who were treated with EGFR-tyrosine kinase inhibitors (TKIs) and had an average H-score >100 had a longer OS time compared with those with an average H-score <100. The interobserver concordance for the total H-scores were 0.982, 0.980 and 0.988, and for a positive H-score ≥200, the interobserver concordance was 0.773, 0.710 and 0.675, respectively. The determination of EGFR expression by the H-score method is highly reproducible among pathologists and is a prognostic factor associated with a poor OS in all patients. Additionally, the results of the present study suggest that patients with EGFR mutations that are treated with EGFR-TKIs and present with a high H-score have a longer OS time.