Integrative gene expression profiling reveals that dysregulated triple microRNAs confer paclitaxel resistance in non-small cell lung cancer via co-targeting MAPT

Decoding the key compounds and mechanism of Shashen Maidong decoction in the treatment of lung cancer

BACKGROUND

Lung cancer is a malignant tumour with the fastest increase in morbidity and mortality around the world. The clinical treatments available have significant side effects, thus it is desirable to identify alternative modalities to treat lung cancer. Shashen Maidong decoction (SMD) is a commonly used traditional Chinese medicine (TCM) formula for treating lung cancer in the clinic. While the key functional components (KFC) and the underlying mechanisms of SMD treating lung cancer are still unclear.

METHODS

We propose a new integrated pharmacology model, which combines a novel node-importance calculation method and the contribution decision rate (CDR) model, to identify the KFC of SMD and to deduce their mechanisms in the treatment of lung cancer.

RESULTS

The enriched effective Gene Ontology (GO) terms selected from our proposed node importance detection method could cover 97.66% of enriched GO terms of reference targets. After calculating CDR of active components in key functional network, the first 82 components covered 90.25% of the network information, which were defined as KFC. 82 KFC were subjected to functional analysis and experimental validation. 5-40 μM protocatechuic acid, 100-400 μM paeonol or caffeic acid exerted significant inhibitory activity on the proliferation of A549 cells. The results show that KFC play an important therapeutic role in the treatment of lung cancer by targeting Ras, AKT, IKK, Raf1, MEK, and NF-κB in the PI3K-Akt, MAPK, SCLC, and NSCLC signaling pathways active in lung cancer.

CONCLUSIONS

This study provides a methodological reference for the optimization and secondary development of TCM formulas. The strategy proposed in this study can be used to identify key compounds in the complex network and provides an operable test range for subsequent experimental verification, which greatly reduces the experimental workload.

LINC02126 is a potential diagnostic, prognostic and immunotherapeutic target for lung adenocarcinoma

Background

Adenocarcinoma has long been an independent histological class of lung cancer, which leads to high morbidity and mortality. We aimed to investigate the contribution of LINC02126 in lung adenocarcinoma.

Methods

RNA sequencing data and clinical information were downloaded. Diagnostic efficiency and survival analysis of LINC02126 were performed, followed by functional analysis of genes co-expressed with LINC02126 and differentially expressed genes (DEGs) in different LINC02126 expression groups. Tumor immune microenvironment (TIME) cell infiltration and correlation analysis of tumor mutation burden were performed in different LINC02126 expression groups.

Results

In lung adenocarcinoma, the expression level of LINC02126 was significantly decreased. Significant expression differences of LINC02126 were found in some clinical variables, including T staging, M staging, sex, stage, and EGFR mutation. LINC02126 had potential diagnostic and prognostic value for patients. In the low LINC02126 expression group, the infiltration degree of most immune cells was significantly lower than that in the high LINC02126 expression group. Tumor mutation burden level and frequency of somatic mutation in patients with low LINC02126 expression group were significantly higher than in patients with high LINC02126 expression group.

Conclusions

LINC02126 could be considered as a diagnostic, prognostic and immunotherapeutic target for lung adenocarcinoma.

A functional methylation signature to predict the prognosis of Chinese lung adenocarcinoma based on TCGA

Background

Lung cancer is the leading cause of cancer morbidity and mortality worldwide, however, the individualized treatment is still unsatisfactory. DNA methylation can affect gene regulation and may be one of the most valuable biomarkers in predicting the prognosis of lung adenocarcinoma. This study was aimed to identify methylation CpG sites that may be used to predict lung adenocarcinoma prognosis.

Methods

The Cancer Genome Atlas (TCGA) database was used to detect methylation CpG sites associated with lung adenocarcinoma prognosis and construct a methylation signature model. Then, a Chinese cohort was carried out to estimate the association between methylation and lung adenocarcinoma prognosis. Biological function studies, including demethylation treatment, cell proliferative capacity, and gene expression changes in lung adenocarcinoma cell lines, were further performed.

Results

In the TCGA set, three methylation CpG sites were selected that were associated with lung adenocarcinoma prognosis (cg14517217, cg15386964, and cg18878992). The risk of mortality was increased in lung adenocarcinoma patients with the gradual increase level of methylation signature based on three methylation sites levels (HR = 45.30, 95% CI = 26.69–66.83; p < 0.001). The C‐statistic value increased to 0.77 when age, gender, and other clinical variables were added to the signature to prediction model. A similar situation was confirmed in Chinese lung adenocarcinoma cohort. In the biological function studies, the proliferative capacity of cell lines was inhibited when the cells were demethylated with 5‐aza‐2'‐deoxycytidine (5‐aza‐2dC). The mRNA and protein expression levels of SEPT9 and HIST1H2BH (cg14517217 and cg15386964) were downregulated with different concentrations of 5‐aza‐2dC treatment, while cg18878992 showed the opposite result.

Conclusion

This study is the first to develop a three‐CpG‐based model for lung adenocarcinoma, which is a practical and useful tool for prognostic prediction that has been validated in a Chinese population.

Network-based approach to identify prognosis-related genes in tamoxifen-treated patients with estrogen receptor-positive breast cancer

Tamoxifen is an estrogen receptor (ER) antagonist that is most commonly used for the treatment of ER-positive breast cancer. However, tamoxifen resistance remains a major cause of cancer recurrence and progression. Here, we aimed to identify hub genes implicated in the progression and prognosis of ER-positive breast cancer following tamoxifen treatment. Microarray data (GSE9893) for 155 tamoxifen-treated primary ER-positive breast cancer samples were obtained from the Gene Expression Omnibus database. In total, 1706 differentially expressed genes (DEGs), including 859 up-regulated and 847 down-regulated genes, were identified between relapse and relapse-free samples. Weighted correlation network analysis clustered genes into 13 modules, among which the tan and blue modules were the most significantly related to prognosis. From these two modules, we further identified and validated two prognosis-related hub genes (G-rich RNA sequence binding factor 1 (GRSF1) and microtubule-associated protein τ (MAPT)) via survival analysis based on several publicly available datasets. High expression of GRSF1 predicted poor prognosis, whereas MAPT indicated favorable outcomes in ER-positive breast cancer. Using breast cancer cell lines and tissue samples, we confirmed that GRSF1 was significantly up-regulated and MAPT was down-regulated in the tamoxifen-resistant group compared with the tamoxifen-sensitive group. The prognostic value of GRSF1 and MAPT was also verified in 48 tamoxifen-treated ER-positive breast cancer patients in our hospital. Gene set enrichment analysis (GSEA) suggested that GRSF1 was potentially involved in RNA degradation and cell cycle pathways, while MAPT was strongly linked to immune-related signaling pathways. Taken together, our findings established novel prognostic biomarkers to predict tamoxifen sensitivity, which may facilitate individualized management of breast cancer.

Integrative analyses identified ion channel genes GJB2 and SCNN1B as prognostic biomarkers and therapeutic targets for lung adenocarcinoma

OBJECTIVES

Abnormal expressions of ion channel genes are associated with the occurrence and progression of tumors. At present, their roles in the carcinogenesis of lung adenocarcinoma (LUAD) are not clear.

MATERIALS AND METHODS

Differentially expressed (DE) genes in the tumorigenesis were identified from 328 ion channel genes in 102 LUAD and paired adjacent normal samples. Similar analyses were performed between 177 metastatic and 286 non-metastatic LUAD samples to identify DE ion channel genes in the progression of LUAD. Independent prognostic factors selected from DE ion channel genes were used to construct a prognostic model. Correlation analysis and drugs-drug targets interaction network were used to screen the potential drugs for LUAD patients stratified by GJB2 or SCNN1B.

RESULTS

Six ion channel genes (GJB2, CACNA1D, KCNQ1, SCNN1B, SCNN1G and TRPV6) were continuous differentially expressed in the tumorigenesis and progression of LUAD. The survival analysis in four datasets with 522 LUAD samples showed that GJB2 and SCNN1B were independent prognostic biomarkers. Patients with overexpression of GJB2 or underexpression of SCNN1B had shorter overall survival. Moreover, multi-omics analysis showed that hypomethylation of GJB2 and hypermethylation of SCNN1B in the promoter region may contribute to their aberrant expressions. KEGG enrichment analysis showed that the overexpressed genes in the group with high GJB2 or low SCNN1B were enriched in cancer-related pathways, while the underexpressed genes were enriched in metabolism-related pathways. The prognostic model with GJB2 and SCNN1B can stratify all LUAD patients into two groups with significantly different survival. Correlation analysis and drugs-drug targets interaction network suggested that GJB2 and SCNN1B expression might have indicative therapeutic values for LUAD patients. Finally, pan-cancer analysis in other eight cancer types showed that GJB2 and SCNN1B might be also potential prognostic factors for KIRC.

CONCLUSIONS

GJB2 and SCNN1B were identified as prognostic biomarkers and therapeutic targets for LUAD.

Advances and Challenges in Understanding MicroRNA Function in Tauopathies: A Case Study of miR-132/212

In the past decade, several groups have reported that microRNAs (miRNAs) can participate in the regulation of tau protein at different levels, including its expression, alternative splicing, phosphorylation, and aggregation. These observations are significant, since the abnormal regulation and deposition of tau is associated with nearly 30 neurodegenerative disorders. Interestingly, miRNA profiles go awry in tauopathies such as Alzheimer's disease, progressive supranuclear palsy, and frontotemporal dementia. Understanding the role and impact of miRNAs on tau biology could therefore provide important insights into disease risk, diagnostics, and perhaps therapeutics. In this Perspective article, we discuss recent advances in miRNA research related to tau. While proof-of-principle studies hold promise, physiological validation remains limited. To help fill this gap, we describe herein a pure tauopathy mouse model deficient for the miR-132/212 cluster. This miRNA family is strongly downregulated in human tauopathies and shown to regulate tau in vitro and in vivo. No significant differences in survival, motor deficits or body weight were observed in PS19 mice lacking miR-132/212. Age-specific effects were seen on tau expression and phosphorylation but not aggregation. Moreover, various miR-132/212 targets previously implicated in tau modulation were unaffected (GSK-3β, Foxo3a, Mapk1, p300) or, unexpectedly, reduced (Mapk3, Foxo1, p300, Calpain 2) in miR-132/212-deficient PS19 mice. These observations highlight the challenges of miRNA research in living models, and current limitations of transgenic tau mouse models lacking functional miRNA binding sites. Based on these findings, we finally recommend different strategies to better understand the role of miRNAs in tau physiology and pathology.

Circ_0074027 contributes to the progression of non-small cell lung cancer via microRNA-362-3p/clathrin heavy chain axis

Circular RNAs are involved in the occurrence and development of different types of cancers. We aimed to illustrate the expression profile and mechanism of circ_0074027 in non-small cell lung cancer (NSCLC). Quantitative real-time PCR was employed to detect the expression of circ_0074027, paired like homeodomain 1 (PITX1) mRNA (mPITX1) and microRNA-362-3p (miR-362-3p). Western blot assay was utilized to measure the levels of clathrin heavy chain (CLTC), cyclin D1, BCL2-associated X, apoptosis regulator Bax (Bax), vimentin and matrix metallopeptidase 9. The clonogenicity, apoptosis and metastasis of NSCLC cells were examined by colony formation assay, flow cytometry and transwell migration and invasion assays. The target relationship between miR-362-3p and circ_0074027 or CLTC was predicted by starBase website and was validated by dual-luciferase reporter assay. Murine xenograft assay was applied to explore the function of circ_0074027 in vivo. We found that The enrichment of circ_0074027 and CLTC protein was elevated, and a significant reduction in the expression of miR-362-3p was observed in NSCLC tissues and cells relative to adjacent normal tissues and human bronchial epithelial cells 16HBE. Circ_0074027 possessed a stable circular structure. Circ_0074027 and CLTC could accelerate the colony formation and metastasis and suppress the apoptosis of NSCLC cells. Circ_0074027/miR-362-3p/CLTC axis was first found to regulate the malignance of NSCLC cells. The biological influence caused by circ_0074027 depletion on NSCLC cells was alleviated by the accumulation of CLTC. Circ_0074027 acted as an oncogene to promote the growth of NSCLC tumors in vivo. In conclusion, Circ_0074027 contributed to the progression of NSCLC through promoting the proliferation and motility while hampering the apoptosis of NSCLC cells via miR-362-3p/CLTC axis.

Targeting micro-RNAs by natural products: a novel future therapeutic strategy to combat cancer

MicroRNAs are a class of short, non-coding RNAs that play a crucial role in normal physiology by attenuating translation or targeting messenger RNAs for degradation. Deregulation of miRNAs disturbs key molecular events in interconnected processes such as cell proliferation, tumor angiogenesis, self-renewal, apoptosis, metastasis and epithelial to mesenchymal transition. This process initiates, promotes and develops the pathophysiology of cancer. The modulation of miRNAs results in epigenetic changes in the genome, which eventually leads to cancer. Targeting deregulated miRNAs by natural products derived from plants is an ideal strategy to combat tumorigenesis. Owing to their fewer side effects, natural products have been used as chemotherapeutic agents against various cancers. These natural products modulate the dysregulated signaling pathways by downregulating the oncogenic miRNAs which play a crucial role in the development of tumorigenesis and maintain a fine balance of tumor suppressor miRNAs. This review article aims to highlight the key modifications of miRNAs which lead to tumorigenesis and the chemotherapeutic potential of natural products by targeting miRNAs and their possible mechanism of inhibition for developing an effective anti-cancer agent(s). They will have less damaging effects on normal cells for future chemotherapeutics.