Non-small Cell Lung Cancer Epigenomes Exhibit Altered DNA Methylation in Smokers and Never-smokers

Use of DNA methylation patterns for early detection and management of lung cancer: Are we there yet?

Detecting lung cancer early is crucial for improving survival rates, yet it remains a significant challenge due to many cases being diagnosed at advanced stages. This review aims to provide advances in epigenetics which have highlighted DNA methylation patterns as promising biomarkers for early detection, prognosis, and treatment response in lung cancer. Techniques like bisulfite conversion followed by PCR, digital droplet polymerase chain reaction, and next-generation sequencing are commonly used for detecting these methylation patterns, which occur early in the cancer development process and can be detected in non-invasive samples like blood and sputum. Key genes such as SHOX2 and RASSF1A have demonstrated high sensitivity and specificity in clinical studies, making them crucial for diagnostic purposes. However, several challenges remain to be overcome before these biomarkers can be widely adopted for use in clinical practice. Standardizing the assays and validating their effectiveness are critical steps. Additionally, integrating methylation biomarkers with existing diagnostic tools could significantly enhance the accuracy of lung cancer detection, providing a more comprehensive diagnostic approach. Although progress has been made in understanding and utilizing DNA methylation patterns for lung cancer detection, more research and extensive clinical trials are necessary to fully harness their potential. These efforts will help establish the robustness of methylation patterns as biomarkers and therapeutic targets, ultimately leading to better prevention, diagnosis, and treatment strategies for lung cancer. In conclusion, DNA methylation states represent a promising avenue for advancing early detection, accurate diagnosis, and management of lung cancer.

Epigenetic modifications in early stage lung cancer: pathogenesis, biomarkers, and early diagnosis

The integration of liquid biopsy with epigenetic markers offers significant potential for early lung cancer detection and personalized treatment. Epigenetic alterations, including DNA methylation, histone modifications, and noncoding RNA changes, often precede genetic mutations and are critical in cancer progression. In this study, we explore how liquid biopsy, combined with epigenetic markers, can provide early detection of lung cancer, potentially predicting onset up to 4 years before clinical diagnosis. We discuss the challenges of targeting epigenetic regulators, which could disrupt cellular balance if overexploited, and the need for maintaining key gene expressions in therapeutic applications. This review highlights the promise and challenges of using liquid biopsy and epigenetic markers for early-stage lung cancer diagnosis, with a focus on optimizing treatment strategies for personalized and precision medicine.

Molecular mechanism of genetic, epigenetic, and metabolic alteration in lung cancer

Lung cancer, a leading cause of cancer-related deaths worldwide, is primarily linked to smoking, tobacco use, air pollution, and exposure to hazardous chemicals. Genetic alterations, particularly in oncogenes like RAS, EGFR, MYC, BRAF, HER, and P13K, can lead to metabolic changes in cancer cells. These cells often rely on glycolysis for energy production, even in the presence of oxygen, a phenomenon known as aerobic glycolysis. This metabolic shift, along with other alterations, contributes to cancer cell growth and survival. To develop effective therapies, it's crucial to understand the genetic and metabolic changes that drive lung cancer. This review aims to identify specific genes associated with these metabolic alterations and screen phytochemicals for their potential to target these genes. By targeting both genetic and metabolic pathways, we hope to develop innovative therapeutic approaches to combat lung cancer.

Identification of potential core genes in lung cancer and therapeutic traditional Chinese medicine compounds using bioinformatics analysis

Lung cancer (LC) remains the leading cause of cancer-related death. We identified potential therapeutic targets and traditional Chinese medicine (TCM) compounds for LC treatment. GSE43346 and GSE18842 were derived from the Gene Expression Omnibus (GEO) database and used to identify differentially expressed genes (DEGs). Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses were performed using The Database for Annotation, Visualization and Integrated Discovery (DAVID). Protein-protein interactions were analyzed using STRING and Cytoscape software. Hub gene expression was validated using Gene Expression Profiling Interactive Analysis and the Human Protein Atlas. Kaplan-Meier survival analysis was conducted to evaluate the prognostic value of hub genes in patients with LC. Therapeutic TCM compounds were screened using the Comparative Toxicogenomics Database, and DEGs were largely enriched in biological processes, including cell division and mitotic nuclear division, such as the cell cycle and p53 signaling pathways. Elevated expression of hub genes was observed in LC samples. Overexpression of CDC20, CCNB2, and TOP2A is an unfavorable prognostic factor for postprogressive survival in patients with LC. Paclitaxel, quercetin, and rotenone have been identified as active substances in TCM. CDC20, CCNB2, and TOP2A are novel hub genes associated with LC. Paclitaxel, quercetin, and rotenone can be used as therapeutic agents in TCM.

Sense and anti-sense: Role of FAM83A and FAM83A-AS1 in Wnt, EGFR, PI3K, EMT pathways and tumor progression

An increasing number of studies have shown that FAM83A, a member of the family with sequence similarity 83 (FAM83), which consists of eight members, is a key tumor therapeutic target involved in multiple signaling pathways. It has been reported that FAM83A plays essential roles in the regulation of Wnt/β-catenin, EGFR, MAPK, EMT, and other signaling pathways and physiological processes in models of pancreatic cancer, lung cancer, breast cancer, and other malignant tumors. Moreover, the expression of FAM83A could be significantly affected by multiple noncoding RNAs that are dysregulated in malignant tumors, the dysregulation of which is essential for the malignant process. Among these noncoding RNAs, the most noteworthy is the antisense long noncoding (Lnc) RNA of FAM83A itself (FAM83A-AS1), indicating an outstanding synergistic carcinogenic effect between FAM83A and FAM83A-AS1. In the present study, the specific mechanisms by which FAM83A and FAM83A-AS1 cofunction in the Wnt/β-catenin and EGFR signaling pathways were reviewed in detail, which will guide subsequent research. We also described the applications of FAM83A and FAM83A-AS1 in tumor therapy and provided a certain theoretical basis for subsequent drug target development and combination therapy strategies.

Ginsenoside Rg5 induces NSCLC cell apoptosis and autophagy through PI3K/Akt/mTOR signaling pathway

OBJECTIVE

Ginsenoside Rg5 (Rg5) is a minor ginsenoside of ginseng and has a strong anti-tumor potential. This study focused on deciphering the function of Rg5 in non-small cell lung cancer (NSCLC) and investigating its related mechanism.

METHODS

After treating human NSCLC cell lines (H1650 and A549) and bronchial epithelial cells (BEAS-2B) with increasing concentration of Rg5, cell viability was examined using methyl thiazolyl tetrazolium (MTT) assay. NSCLC cell proliferation and apoptosis were evaluated by colony formation assay and flow cytometry, respectively. The levels of proteins associated with cell cycle progression, cell apoptosis, and autophagy as well as the key markers in the PI3K/Akt/mTOR pathway were measured using western blot. A xenograft nude mouse model was established to explore the function of Rg5 in vivo.

RESULTS

NSCLC cell viability was dose- and time-dependently suppressed after Rg5 treatment. Rg5 restrained NSCLC cell proliferation by inducing G2/M phase arrest via regulation of cell cycle-related genes including p21, cyclin B1, and Cdc2. Additionally, Rg5 promoted caspase-dependent apoptosis in NSCLC cells by regulating the intrinsic mitochondrial signaling pathway. Rg5 induced autophagy via the regulation of autophagy-related proteins. The in vivo experiments revealed the inhibitory impact of Rg5 on xenograft growth. Rg5 also inactivated the PI3K/Akt/mTOR signaling pathway in NSCLC cells and mouse tumors.

CONCLUSION

Rg5 induced autophagy and caspase-dependent apoptosis in NSCLC cells by inhibiting the PI3K/Akt/mTOR signaling pathway, suggesting that Rg5 might become a promising and novel anti-tumor agent for the clinical treatment of NSCLC patients.