MicroRNA-103a-3p potentiates chemoresistance to cisplatin in non-small cell lung carcinoma by targeting neurofibromatosis 1

Circulating miR-16-5p, miR-92a-3p and miR-451a are biomarkers of lung cancer in Tunisian patients

Lung cancer is one of the most common type of cancer and, despite significant advances in screening and diagnosis approaches, a large proportion of patients at diagnosis still present advanced stages of the disease with distant metastasis and bad prognosis. Finding and validating biomarkers of lung cancer is therefore essential. Such studies are often conducted on European, American and Asian populations and the relevance of these biomarkers in other populations remains less clear. In that prospect, we investigated the expression level of seven microRNAs, chosen from the medical literature (miR-16-5p, miR-92a-3p, miR-103a-3p, miR-375-3p, miR-451a, miR-520-3p and miR-let-7e-5p), in the blood of Tunisian lung cancer patients, treated or not by chemotherapy, and healthy control individuals. We found that high expression levels of circulating miR-16-5p, miR-92a-3p and miR-451a in the plasma of untreated patients discriminate them from healthy control individuals. In addition, miR-16-5p and miR-451a expression levels are significantly reduced in the plasma of chemotherapy-treated patients compared to untreated patients. Our results confirmed previous work in other populations worldwide and provide further evidence that circulating miR-16-5p, miR-92a-3p and miR-451a potentially regulate key pathways involved in the initiation and progression of cancer.

MicroRNAs and Drug Resistance in Non-Small Cell Lung Cancer: Where Are We Now and Where Are We Going

Lung cancer is the leading cause of cancer-related mortality in the world. The development of drug resistance represents a major challenge for the clinical management of patients. In the last years, microRNAs have emerged as critical modulators of anticancer therapy response. Here, we make a critical appraisal of the literature available on the role of miRNAs in the regulation of drug resistance in non-small cell lung cancer (NSCLC). We performed a comprehensive annotation of miRNAs expression profiles in chemoresistant versus sensitive NSCLC, of the drug resistance mechanisms tuned up by miRNAs, and of the relative experimental evidence in support of these. Furthermore, we described the pros and cons of experimental approaches used to investigate miRNAs in the context of therapeutic resistance, to highlight potential limitations which should be overcome to translate experimental evidence into practice ultimately improving NSCLC therapy.

MicroRNAs as Predictors of Lung-Cancer Resistance and Sensitivity to Cisplatin

BACKGROUND

Platinum-based chemotherapy, cisplatin (DDP) specifically, is the main strategy for treating lung cancer (LC). However, currently, there is a lack of predictive drug-resistance markers, and there is increased interest in the development of a reliable and sensitive panels of markers for DDP chemotherapy-effectiveness prediction. MicroRNAs represent a perspective pool of markers for chemotherapy effectiveness.

OBJECTIVES

Data on miRNAs associated with LC DDP chemotherapy response are summarized and analyzed.

MATERIALS AND METHODS

A comprehensive review of the data in the literature and an analysis of bioinformatics resources were performed. The gene targets of miRNAs, as well as their reciprocal relationships with miRNAs, were studied using several databases.

RESULTS AND DISCUSSION

The complex analysis of bioinformatics resources and the literature indicated that the expressions of 12 miRNAs have a high predictive potential for LC DDP chemotherapy responses. The obtained information was discussed from the point of view of the main mechanisms of LC chemoresistance.

CONCLUSIONS

An overview of the published data and bioinformatics resources, with respect to the predictive microRNA markers of chemotherapy response, is presented in this review. The selected microRNAs and gene panel have a high potential for predicting LC DDP sensitiveness or DDP resistance as well as for the development of a DDP co-therapy.

Contribution of MicroRNAs in Chemoresistance to Cisplatin in the Top Five Deadliest Cancer: An Updated Review

Cisplatin (DDP) is a well-known anticancer drug used for the treatment of numerous human cancers in solid organs, including bladder, breast, cervical, head and neck squamous cell, ovarian, among others. Its most important mode of action is the DNA-platinum adducts formation, inducing DNA damage response, silencing or activating several genes to induce apoptosis; these mechanisms result in genetics and epigenetics modifications. The ability of DDP to induce tumor cell death is often challenged by the presence of anti-apoptotic regulators, leading to chemoresistance, wherein many patients who have or will develop DDP-resistance. Cancer cells resist the apoptotic effect of chemotherapy, being a problem that severely restricts the successful results of treatment for many human cancers. In the last 30 years, researchers have discovered there are several types of RNAs, and among the most important are non-coding RNAs (ncRNAs), a class of RNAs that are not involved in protein production, but they are implicated in gene expression regulation, and representing the 98% of the human genome non-translated. Some ncRNAs of great interest are long ncRNAs, circular RNAs, and microRNAs (miRs). Accumulating studies reveal that aberrant miRs expression can affect the development of chemotherapy drug resistance, by modulating the expression of relevant target proteins. Thus, identifying molecular mechanisms underlying chemoresistance development is fundamental for setting strategies to improve the prognosis of patients with different types of cancer. Therefore, this review aimed to identify and summarize miRs that modulate chemoresistance in DDP-resistant in the top five deadliest cancer, both in vitro and in vivo human models.

LncRNA LINC01116 Contributes to Cisplatin Resistance in Lung Adenocarcinoma

Background

Long non-coding RNAs (lncRNAs) have been found to contribute to cisplatin resistance in several cancers; however, the role of lncRNA LINC01116 in cisplatin resistance remains unknown in non-small-cell lung cancer. This study aimed to examine the contribution of LINC01116 to cisplatin resistance in lung adenocarcinoma (LAD).

Materials and Methods

Cisplatin-resistant A549/DDP cells were generated by treatment with cisplatin by dose escalation. LINC01116 expression was compared between A549 and A549/DDP cells, and between cisplatin-resistant and non-resistant LAD specimens. The cell viability, colony formation, proliferation, migration and invasion were measured using MTT and Transwell assays, and cell apoptosis and cell cycle were detected using flow cytometry. The expression of E-cadherin and Vimentin was quantified. LAD xenografts were modeled in nude mice to investigate the role of LINC01116 on the resistance of LAD to cisplatin.

Results

MTT assay measured the IC₅₀ values of 13.49 ± 1.62 and 3.52 ± 1.33 μg/mL for A549/DDP and A549 cells, respectively. LINC01116 was overexpressed in cisplatin-resistant LAD specimens and A549/DDP cells (P < 0.05). Knockdown of LINC01116 inhibited cell viability, proliferation, migration and invasion, promoted apoptosis and enhanced the sensitivity to cisplatin in A549/DDP cells, while LINC01116 overexpression promoted cell viability, proliferation, migration and invasion, inhibited apoptosis and reduced the sensitivity to cisplatin in A549 cells. LINC01116 knockdown resulted in a 2.1-fold increase in E-cadherin expression and a 56% reduction in Vimentin expression in A549/DDP cells, and LINC01116 overexpression resulted in a 45% reduction in E-cadherin expression and a 1.82-fold increase in Vimentin expression in A549 cells.

Conclusion

Dysregulation of lncRNA LINC01116 expression results in resistance of LAD to cisplatin via the EMT process. Our findings support the oncogenic role of LINC01116 to promote the development of cisplatin resistance in LAD, and LINC01116 may be a novel predictor of poor response to cisplatin.

Knockdown of miR-183 Enhances the Cisplatin-Induced Apoptosis in Esophageal Cancer Through Increase of FOXO1 Expression

Background

As an important member of platinum-based chemotherapeutic drugs, cisplatin is effective and is commonly used in the treatment of esophageal cancer. However, repeated use of cisplatin usually causes severe side-effects on patients. Novel approaches should be explored to increase the sensitivity of cancer cells to cisplatin.

Methods

The expression level of miR-183 in esophageal cancer tissues and cell lines was measured by quantitative reverse transcriptase real-time PCR (qRT-PCR). The sensitivity of EC cell lines to cisplatin was evaluated by CCK-8 assay and flow cytometry. Luciferase reporter assay was used to confirm the association between miR-183 and FOXO1. The apoptosis pathway of EC cells was tested by Western blot assay.

Results

The expression level of miR-183 was increased in esophageal cancer patients' tumor tissues and esophageal cancer cell lines. However, knockdown of miR-183 was found to enhance the effect of cisplatin on inducing the apoptotic cell death of esophageal cancer cells. In the mechanism research, we proved that FOXO1 was the target of miR-183 in esophageal cancer cells. Inhibition of miR-183 increased the expression of FOXO1 to promote the expression of Bim and Noxa. As Bim and Noxa acted as key pro-apoptotic proteins in mitochondrial apoptosis, inhibition of miR-183 enhanced the cisplatin-induced apoptosis pathway in esophageal cancer.

Conclusion

Knockdown of miR-183 enhanced the cisplatin-induced apoptosis in esophageal cancer through an increase of FOXO1 expression.

MiR-140 Resensitizes Cisplatin-Resistant NSCLC Cells to Cisplatin Treatment Through the SIRT1/ROS/JNK Pathway

Background

Although cisplatin is an effective chemotherapeutic drug that is commonly used for non-small-cell lung cancer (NSCLC) treatment, the drug resistance usually occurs during the long-term use of it. It is urgent to develop strategies to reduce the resistance of NSCLC cells to cisplatin.

Methods

Cisplatin-resistant NSCLC cell lines (PC9/R and A549/R) were acquired through long-term exposure of PC9 and A549 cells to cisplatin. QRT-PCR analysis was performed to compare the expression of miR-140 between routine NSCLC cells and cisplatin-resistant NSCLC cells. CCK-8 assay was used to evaluate the effect of miR-140 on the sensitivity of PC9/R and A549/R to cisplatin. Western blot assay and luciferase reporter assay were used to confirm the regulation of miR-140 on SIRT1. Western blot and flow cytometry analysis were performed to evaluate the effect of miR-140 on the apoptosis pathway induced by cisplatin.

Results

PC9/R and A549/R exhibited obviously lower sensitivity compared to their parental PC9 and A549 cells, respectively. Furthermore, PC9/R and A549/R cells expressed significantly lower levels of miR-140 compared to their parental PC9 and A549 cells, respectively. However, transfection with miR-140 mimics significantly resensitized the PC9/R and A549/R to cisplatin-induced cytotoxicity. In the mechanism research, we confirmed that SIRT1 was overexpressed and was targeted by miR-140 in PC9/R and A549/R. Furthermore, overexpression of SIRT1 was responsible for the resistance to cisplatin in PC9/R and A549/R cells. Transfection with miR-140 was able to inhibit the expression of SIRT1 and thus inhibited the SIRT1/ROS/JNK pathway. As a result, the PC9/R and A549/R cells restored the sensitivity to cisplatin-induced apoptosis.

Conclusion

MiR-140 resensitizes cisplatin-resistant NSCLC cells to cisplatin treatment through the SIRT1/ROS/JNK pathway.