Tumor suppressor microRNAs in lung cancer: An insight to signaling pathways and drug resistance

Oleuropein induces apoptosis in gastric cancer cell lines by regulating mir-34a, mir-21, and related genes: An experimental and bioinformatic study

Gastric Cancer (GC) is one of the most prevalent malignancies worldwide. Oleuropein, as a natural phenolic compound with anti-cancer characteristics, is a good option with low side effects to overcome the adverse impact of conventional treatments in cancer. This research evaluated Oleuropein's anti-cancer and apoptotic activities and the anti-migratory effects by modulating potential target genes in epithelial-mesenchymal transition (EMT). Bioinformatic analysis was performed to predict possible Oleuropein's target genes. Then the importance of these genes was shown by UALCAN, Gene Expression Omnibus (GEO), and The Cancer Genome Atlas (TCGA) datasets in gastric cancer. Finally, the association between the selected genes was shown by Cytoscape network analysis. The MTT assay, DAPI staining, flow cytometry, and real-time PCR were applied in the current study. The results showed that the viability of cells was decreased, and the apoptosis rate increased in the Oleuropein-treated group. These findings revealed that Oleuropein regulated the expression of the apoptotic and metastatic genes and microRNAs in GC cells.

Recent advances on high-efficiency of microRNAs in different types of lung cancer: a comprehensive review

Carcinoma of the lung is among the most common types of cancer globally. Concerning its histology, it is categorized as a non-small cell carcinoma (NSCLC) and a small cell cancer (SCLC) subtype. MicroRNAs (miRNAs) are a member of non-coding RNA whose nucleotides range from 19 to 25. They are known to be critical regulators of cancer via epigenetic control of oncogenes expression and by regulating tumor suppressor genes. miRNAs have an essential function in a tumorous microenvironment via modulating cancer cell growth, metastasis, angiogenesis, metabolism, and apoptosis. Moreover, a wide range of information produced via several investigations indicates their tumor-suppressing, oncogenic, diagnostic assessment, and predictive marker functions in different types of lung malignancy. miRNA mimics or anti-miRNAs can be transferred into a lung cancer cell, with possible curative implications. As a result, miRNAs hold promise as targets for lung cancer treatment and detection. In this study, we investigate the different functions of various miRNAs in different types of lung malignancy, which have been achieved in recent years that show the lung cancer-associated regulation of miRNAs expression, concerning their function in lung cancer beginning, development, and resistance to chemotherapy, also the probability to utilize miRNAs as predictive biomarkers for therapy reaction.

MicroRNA-143 as a potential tumor suppressor in cancer: An insight into molecular targets and signaling pathways

MicroRNAs (MiRNAs), which are highly conserved and small noncoding RNAs, negatively regulate gene expression and influence signaling pathways involved in essential biological activities, including cell proliferation, differentiation, apoptosis, and cell invasion. MiRNAs have received much attention in the past decade due to their significant roles in cancer development. In particular, microRNA-143 (miR-143) is recognized as a tumor suppressor and is downregulated in most cancers. However, it seems that miR-143 is upregulated in rare cases, such as prostate cancer stem cells, and acts as an oncogene. The present review will outline the current studies illustrating the impact of miR-143 expression levels on cancer progression and discuss its target genes and their relevant signaling pathways to discover a potential therapeutic way for cancer.

MicroRNA based combinatorial therapy against TKIs resistant CML by inactivating the PI3K/Akt/mTOR pathway: a review

Chronic myeloid leukemia (CML) is characterized by presence of Philadelphia chromosome, which harbors BCR-ABL oncogene responsible for encoding BCR-ABL oncoprotein. This oncoprotein interferes with cellular signaling pathways, resulting in tumor progression. Among these pathways, PI3K/Akt/mTOR pathway is significantly upregulated in CML. Tyrosine kinase inhibitors (TKIs) are current standard therapy for CML, and they have shown remarkable efficacy. However, emergence of TKIs drug resistance has necessitated investigation of novel therapeutic approaches. Components of PI3K/Akt/mTOR pathway have emerged as attractive targets in this context, as this pathway is known to be activated in TKIs-resistant CML cells/patients. Inhibiting this pathway may provide a complementary approach to improving TKIs' efficacy and treatment outcomes. Given previous research indicating that miRNAs play an inhibitory role in cancer, current study used computational tools to identify miRNAs that specifically target pathway's core components. A comprehensive analysis was performed, resulting in identification of 111 miRNAs that potentially target PI3K/Akt/mTOR pathway. From this extensive list, 7 miRNAs was selected for further investigation based on their consistent downregulation across leukemia subtypes. Except for hsa-miR-199a-3p, remaining six miRNAs have been extensively studied in acute myeloid leukemia (AML). Given high similarity between AML and CML, it is believed that six miRNAs which are not studied in context of CML may also be advantageous for curing chemoresistance in CML. Building upon this knowledge, it is reasonable to speculate that a combination therapy approach involving use of miRNAs alongside TKIs may offer improved therapy for TKIs-resistant CML compared to TKIs monotherapy alone.

Non-coding RNAs in lung cancer: molecular mechanisms and clinical applications

Lung cancer (LC) is a heterogeneous disease with high malignant degree, rapid growth, and early metastasis. The clinical outcomes of LC patients are generally poor due to the insufficient elucidation of pathological mechanisms, low efficiency of detection and assessment methods, and lack of individualized therapeutic strategies. Non-coding RNAs (ncRNAs), including microRNA (miRNA), long non-coding RNA (lncRNA), and circular RNA (circRNA), are endogenous regulators that are widely involved in the modulation of almost all aspects of life activities, from organogenesis and aging to immunity and cancer. They commonly play vital roles in various biological processes by regulating gene expression via their interactions with DNA, RNA, or protein. An increasing amount of studies have demonstrated that ncRNAs are closely correlated with the initiation and development of LC. Their dysregulation promotes the progression of LC via distinct mechanisms, such as influencing protein activity, activating oncogenic signaling pathways, or altering specific gene expression. Furthermore, some ncRNAs present certain clinical values as biomarker candidates and therapeutic targets for LC patients. A complete understanding of their mechanisms in LC progression may be highly beneficial to developing ncRNA-based therapeutics for LC patients. This review mainly focuses on the intricate mechanisms of miRNA, lncRNA, and circRNA involved in LC progression and discuss their underlying applications in LC treatment.

Multi-Drug Resistance against Second-Line Medication and MicroRNA Plasma Level in Metastatic Breast Cancer Patients

Background

Circulating microRNAs (miRNAs) can help to predict the chemotherapy response in breast cancer with promising results. The aim of the present study was to investigate the relationships between the miR-199a, miR-663a, and miR-663b expression and chemotherapy response in metastatic breast cancer patients.

Methods

This study is a case-control study performed at Yasuj University of Medical Sciences (2018-2021). The expression levels of miR-663a, miR-663b, and miR-199a in the serum of 25 patients with metastatic breast cancer versus 15 healthy individuals were determined by the real-time polymerase chain reaction method. The response to treatment was followed up in a 24-month period. All patients were treated with second-line medications. Two or more combinations of these drugs were used: gemcitabine, Navelbine^®, Diphereline^®, Xeloda^®, letrozole, Aromasin^®, and Zolena^®. Statistical analyses were performed in SPSS 21.0 and GraphPad Prism 6 software. The expression levels were presented as mean±SD and analyzed by Student's t test.

Results

The results and clinicopathological features of patients were analyzed by t test. The statistical analysis showed that miR-663a expression was related to human epidermal growth factor receptor 2 (HER2) status and was significantly lower in the HER2⁺ than HER2^- group (P=0.027). Moreover, the expression of miR-199a and miR-663b was significantly correlated with the response to treatment, in which the expression of miR-199a was higher in the poor-response group (P=0.049), while the higher expression of miR-663b was seen in the good-response group (P=0.009).

Conclusion

These findings state that the high plasma level of miR-199a and the low plasma level of miR-663b may be related to chemoresistance in patients with metastatic breast cancer.

A Quality by Design Approach in Pharmaceutical Development of Non-Viral Vectors with a Focus on miRNA

Cancer is the leading cause of death worldwide. Tumors consist of heterogeneous cell populations that have different biological properties. While conventional cancer therapy such as chemotherapy, radiotherapy, and surgery does not target cancer cells specifically, gene therapy is attracting increasing attention as an alternative capable of overcoming these limitations. With the advent of gene therapy, there is increasing interest in developing non-viral vectors for genetic material delivery in cancer therapy. Nanosystems, both organic and inorganic, are the most common non-viral vectors used in gene therapy. The most used organic vectors are polymeric and lipid-based delivery systems. These nanostructures are designed to bind and protect the genetic material, leading to high efficiency, prolonged gene expression, and low toxicity. Quality by Design (QbD) is a step-by-step approach that investigates all the factors that may affect the quality of the final product, leading to efficient pharmaceutical development. This paper aims to provide a new perspective regarding the use of the QbD approach for improving the quality of non-viral vectors for genetic material delivery and their application in cancer therapy.

MicroRNA-143 act as a tumor suppressor microRNA in human lung cancer cells by inhibiting cell proliferation, invasion, and migration

BACKGROUND/AIM

MicroRNAs play crucial roles in controlling cellular biological processes. miR-143 expression is usually downregulated in different cancers. In this study, we focused on exploring the role of miR143 in NSCLC development.

METHODS

Bioinformatics analyses were used to detect the expression level of miR-143 in lung tumors. The cells were transfected by pCMV-miR-143 vectors. The efficacy of transfection was verified by Flow cytometry. The influence of miR-143 replacement on NSCLC cells migration, proliferation, and apoptosis was detected using wound-healing assay, MTT assay, and DAPI staining, respectively.

RESULTS

MTT assay revealed that overexpression of miR143 inhibited cell growth and proliferation. Scratch assay results demonstrated that restoration of miR143 suppressed cell migration. The qRT-PCR assay was further used to detect the assumed relationship between miR143 and apoptotic and metastatic-related genes.

CONCLUSION

The findings showed that miR-143 could reduce cell proliferation, invasion, and migration by reducing CXCR4, Vimentin, MMP-1, Snail-1, C-myc expression level, and increasing E-cadherin expression levels in lung cancer cells and might be a potential target in NSCLC's targeted therapy.

Novel Effects of Statins on Cancer via Autophagy

Cancer is one of the main causes of death globally. Most of the molecular mechanisms underlying cancer are marked by complex aberrations that activate the critical cell-signaling pathways that play a pivotal role in cell metabolism, tumor development, cytoskeletal reorganization, and metastasis. The phosphatidylinositol 3-kinase/protein kinase-B/mammalian target of the rapamycin (PI3K/AKT/mTOR) pathway is one of the main signaling pathways involved in carcinogenesis and metastasis. Autophagy, a cellular pathway that delivers cytoplasmic components to lysosomes for degradation, plays a dual role in cancer, as either a tumor promoter or a tumor suppressor, depending on the stage of the carcinogenesis. Statins are the group of drugs of choice to lower the level of low-density lipoprotein (LDL) cholesterol in the blood. Experimental and clinical data suggest the potential of statins in the treatment of cancer. In vitro and in vivo studies have demonstrated the molecular mechanisms through which statins inhibit the proliferation and metastasis of cancer cells in different types of cancer. The anticancer properties of statins have been shown to result in the suppression of tumor growth, the induction of apoptosis, and autophagy. This literature review shows the dual role of the autophagic process in cancer and the latest scientific evidence related to the inducing effect exerted by statins on autophagy, which could explain their anticancer potential.

miR-520a-5p regulates Frizzled 9 expression and mediates effects of cigarette smoke and iloprost chemoprevention

Expression of Frizzled 9 (FZD9) is critical to the activity of the lung cancer chemoprevention agent and prostacyclin analogue, iloprost. FZD9 is required in lung epithelial cells for iloprost to activate peroxisome proliferator activated receptor gamma (PPARG) and related anti-tumor signaling. We aimed to investigate which miRNA regulate FZD9 in the context of cigarette smoke exposure and iloprost treatment. We found that miR-520a-5p binds the FZD9 3’UTR in lung cell lines and alters activity and expression of FZD9 downstream targets. Cigarette smoke condensate (CSC) increases expression of miR-520a-5p, while iloprost decreases expression. Cancer promoting effects of a miR-520a-5p mimic were rescued with iloprost treatment, and effects of cigarette smoke were partially rescued with a miR-520a-5p inhibitor. Here we confirm miR-520a-5p as a regulator of FZD9 activity and a mediator of CSC and iloprost effects in the lung. Targeting miR-520a-5p could be an approach to restoring FZD9 expression and improving response to iloprost lung cancer chemoprevention.

Inhibition of miR-185-3p Confers Erlotinib Resistance Through Upregulation of PFKL/MET in Lung Cancers

Erlotinib (ER), as an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), has a significant therapeutic effect in lung cancers. However, EGFR TKI resistance inevitably occurs after treatment for approximately 12 months, which weakens its antitumor effect. Here, we identified miR-185-3p as a significantly downregulated microRNA responsible for acquired EGFR TKI resistance in cells and patients with lung cancer. qRT-PCR and Western Blot were performed to determine the relative expression of miR-185-3p in ER-resistant tumor tissues and cells. The viability and apoptosis of lung cancer cells were evaluated by Cell Counting Kit-8 (CCK8) assay and flow cytometry, respectively. The binding between miR-185-3p and liver-type phosphofructokinase (PFKL) was verified by dual luciferase assay. It was found that overexpression of miR-185-3p conferred ER sensitivity in lung cancer cell lines. MiR-185-3p was downregulated in ER-resistant lung cancer cells (H1299/ER and A549/ER). MiR-185-3p inhibited proliferation and induced cell apoptosis in ER-resistant cells. Mechanistically, miR-185-3p downregulation contributed to ER resistance through upregulating the PFKL. Moreover, Mesenchymal to epithelial transition (MET) oncoprotein promoted EGFR-TKI resistance by regulating miR-185-3p and PFKL. These findings revealed a novel mechanism in which downregulation of miR-185-3p may induce overexpression of PFKL and MET and confer ER resistance in lung cells. Combination of PFKL/MET inhibitors and EGFR TKIs could be a rational therapeutic approach for lung cancer patients with EGFR mutation.

In vivo miRNA knockout screening identifies miR-190b as a novel tumor suppressor

MicroRNAs (miRNAs) play important roles in the development of various cancers including lung cancer which is one of the devastating diseases worldwide. How miRNAs function in de novo lung tumorigenesis remains largely unknown. We here developed a CRISPR/Cas9-mediated dual guide RNA (dgRNA) system to knockout miRNAs in genetically engineered mouse model (GEMM). Through bioinformatic analyses of human lung cancer miRNA database, we identified 16 downregulated miRNAs associated with malignant progression and performed individual knockout with dgRNA system in KrasG12D/Trp53L/L (KP) mouse model. Using this in vivo knockout screening, we identified miR-30b and miR-146a, which has been previously reported as tumor suppressors and miR-190b, a new tumor-suppressive miRNA in lung cancer development. Over-expression of miR-190b in KP model as well as human lung cancer cell lines significantly suppressed malignant progression. We further found that miR-190b targeted the Hus1 gene and knockout of Hus1 in KP model dramatically suppressed lung tumorigenesis. Collectively, our study developed an in vivo miRNA knockout platform for functionally screening in GEMM and identified miR-190b as a new tumor suppressor in lung cancer.

Restoration of miR-330 expression suppresses lung cancer cell viability, proliferation, and migration

Lung cancer is one of the most common cancers and its incidence is rising around the world. Various studies suggest that miR-330 acts as a tumor-suppressor microRNA (miRNA) in different types of cancers, but precisely how has remained unclear. In this study, we investigate miR-330 expression in lung cancer patient samples, as well as in vitro, by studying how normalization of miR-330 expression affects lung cancer cellular phenotypes such as viability, apoptosis, proliferation, and migration. We establish that low miR-330 expression predicts poor lung cancer prognosis. Stable restoration of reduced miR-330 expression in lung cancer cells reduces cell viability, increases the fraction of apoptotic cells, causes G2/M cell cycle arrest, and inhibits cell migration. These findings are substantiated by increased mRNA and protein expression of markers for apoptosis via the intrinsic pathway, such as caspase 9, and decreased mRNA and protein expression of markers for cell migration, such as vimentin, C-X-C chemokine receptor type 4, and matrix metalloproteinase 9. We showed that reduced miR-330 expression predicts poor lung cancer survival and that stable restoration of miR-330 expression in lung cancer cells has a broad range of tumor-suppressive effects. This indicates that miR-330 is a promising candidate for miRNA replacement therapy for lung cancer patients.

[MiR-665 Promotes the Biological Behavior of Small Cell Lung Cancer by Targeting LLGL1]

背景与目的

MicroRNAs（miRNAs）是一种广泛存在于真核生物体中的非编码小分子RNA，尽管一些miRNA在肿瘤中作用已被发现，但是miR-665对小细胞肺癌的中的表达及影响还尚不清楚。本研究旨在分析miR-665对肺癌细胞增殖、周期、侵袭和迁移的影响，探讨miR-665在小细胞肺癌中发挥的作用及其工作机制。

方法

qRT-PCR检测miR-665在肺癌组织和癌旁正常组织中的表达水平；TargetScan预测miR-665的潜在靶基因并用双荧光素酶报告基因实验、qRT-PCR和Western blot进行验证；免疫组化、qRT-PCR和Western blot检测LLGL1在肺癌组织和癌旁正常组织中的表达水平；CCK8法、流式细胞法、Transwell和细胞划痕实验检测miR-665和LLGL1对肺癌细胞NCI-H446、NCI-H1688增殖、侵袭、迁移以及S期细胞比值的影响；构建肺癌裸鼠移植瘤模型并观察miR-665对小鼠肿瘤生长的影响。

结果

miR-665在肺癌组织中的表达水平明显高于癌旁正常组织；miR-665能靶向作用于LLGL1的3’-UTR并抑制其表达；相比于癌旁正常组织，LLGL1在肺癌组织中的表达水平明显降低；抑制miR-665的表达可以抑制肺癌NCI-H446细胞的增殖、S期细胞比值、侵袭和迁移能力，而干扰LLGL1能逆转这种抑制效果；上调miR-665则促进肺癌NCI-H1688的增殖、S期细胞比值、侵袭和迁移能力，但这种促进效果同样被LLGL1的过表达逆转；在肺癌裸鼠移植瘤模型中，抑制miR-665能上调LLGL1蛋白的表达并抑制肿瘤的生长，而上调miR-665的表达则可以产生相反的结果。

结论

miR-665表达水平的变化与肺癌密切相关，miR-665可以通过抑制其靶基因LLGL1的表达促进肺癌细胞的生物学行为，在小细胞肺癌中发挥促癌基因的作用。

Identifying critical state of complex diseases by single-sample Kullback-Leibler divergence

Background

Developing effective strategies for signaling the pre-disease state of complex diseases, a state with high susceptibility before the disease onset or deterioration, is urgently needed because such state usually followed by a catastrophic transition into a worse stage of disease. However, it is a challenging task to identify such pre-disease state or tipping point in clinics, where only one single sample is available and thus results in the failure of most statistic approaches.

Methods

In this study, we presented a single-sample-based computational method to detect the early-warning signal of critical transition during the progression of complex diseases. Specifically, given a set of reference samples which were regarded as background, a novel index called single-sample Kullback–Leibler divergence (sKLD), was proposed to explore and quantify the disturbance on the background caused by a case sample. The pre-disease state is then signaled by the significant change of sKLD.

Results

The novel algorithm was developed and applied to both numerical simulation and real datasets, including lung squamous cell carcinoma, lung adenocarcinoma, stomach adenocarcinoma, thyroid carcinoma, colon adenocarcinoma, and acute lung injury. The successful identification of pre-disease states and the corresponding dynamical network biomarkers for all six datasets validated the effectiveness and accuracy of our method.

Conclusions

The proposed method effectively explores and quantifies the disturbance on the background caused by a case sample, and thus characterizes the criticality of a biological system. Our method not only identifies the critical state or tipping point at a single sample level, but also provides the sKLD-signaling markers for further practical application. It is therefore of great potential in personalized pre-disease diagnosis.