PTEN and PI3K/AKT in non-small-cell lung cancer

ACY1 regulating PTEN/PI3K/AKT signaling in the promotion of non-small cell lung cancer progression

Background

Non-small cell lung cancer (NSCLC) has a poor prognosis and is the most common cause of cancer-related deaths worldwide. Aminoacylase 1 (ACY1) plays a promoting role in some cancers, but its role in NSCLC is still unclear.

Methods

Immunohistochemistry, Reverse transcription-polymerase chain reaction (RT-PCR) and western blotting assays were used to determine ACY1 expression patterns in NSCLC tissues and cell lines. The clinical significance of ACY1 in NSCLC was evaluated by χ² test and Kaplan-Meier analysis. MTT, flow cytometry, wound healing, and Transwell assays were performed to assess cell growth, apoptosis, migration, invasion, and tumorigenesis under different treatments. Male athymic BALB/C nude mice were used for xenotransplantation experiments.

Results

The results showed that ACY1 expression was elevated in NSCLC tissue samples and cells, and high ACY1 expression predicted an advanced clinical process and shorter overall survival in patients with NSCLC. Overexpression of ACY1 significantly increased cell growth, migration, invasion, and tumorigenesis, and reduced cell apoptosis, indicating that ACY1 functions as an oncogene in NSCLC. Moreover, ACY1 decreased phosphatase and tensin homolog (PTEN) expression, increased its ubiquitination, and activated PI3K/AKT signaling. Overexpression of PTEN diminished the effects of ACY1 upregulation on cell tumorigenesis promotion.

Conclusions

This study reveals that ACY1 may promote the progression of NSCLC via activating PI3K/AKT signaling in a PTEN-dependent manner. Our study may provide a better understanding of the pathogenesis and development of NSCLC.

Non-small cell lung cancer cell-derived exosomal miR-17-5p promotes osteoclast differentiation by targeting PTEN

Aberrant activity of bone resorbing osteoclasts plays a key role in the development of osteoporosis and cancer bone metastasis. The identification of novel and specific targets will be helpful for the development of new therapeutic strategies for bone metastasis in lung cancer. Herein, we examined microRNAs in tumor cell-derived exosomes to investigate the communication between the bone environment and tumor cells. TCGA database analysis showed that the level of miR-17-5p increased in non-small cell lung cancer tissues compared with non-tumor tissues. To investigate the function of exosomes in inducing osteoclastogenesis, osteoclast precursors were incubated with exosomes isolated from non-small cell lung cancer cell line, as well as receptor activator of NF-KB ligand and M-CSF to induce osteoclastogenesis. We found that exosomal miR-17-5p is upregulated in a non-small cell lung cancer cell line with bone metastasis compared with the original cell line. Overexpression of miR-17-5p enhanced the osteoclastogenesis of RAW264.7 cells. PTEN was identified as a direct target of miR-17-5p and showed negative effects on osteoclastogenesis. Importantly, treatment of LY294002 (an inhibitor of the PI3K/Akt pathway) attenuated miR-17-5p-mediated osteoclastogenesis effects. Taken together, our findings demonstrated that miR-17-5p promotes osteoclastogenesis through the PI3K/Akt pathway via targeting PTEN in lung cancer.

Low sodium and tolvaptan have opposite effects in human small cell lung cancer cells

PURPOSE

Hyponatraemia is frequently observed in cancer patients and can be due to the syndrome of inappropriate anti-diuresis (SIAD), related to ectopic vasopressin secretion, particularly in small cell lung cancer (SCLC). Hyponatraemia is associated with a worse outcome in cancer patients. The vasopressin receptor antagonist tolvaptan effectively corrects hyponatraemia secondary to SIAD and there is in vitro evidence that it has also an antiproliferative effect in cancer cells. The purpose of this study was i) to analyse the effect of low serum sodium concentrations ([Na⁺]) in SCLC cells and ii) to determine whether tolvaptan counteracts tumor progression.

METHODS

We evaluated cell proliferation, cell cycle, apoptosis, oxidative stress, invasivity in low [Na⁺] as well as after exposure to tolvaptan. We also analysed the intracellular signalling pathways involved.

RESULTS

In reduced [Na⁺] cell proliferation was significantly increased compared to normal [Na⁺] and cells were mostly distributed in the G2/M phase. Apoptosis appeared reduced. In addition, the ability to cross matrigel-coated membranes markedly increased. As observed in other cancer cell models, the expression of the heme-oxigenase-1 gene was increased. Finally, we found that in cells cultured in low [Na⁺] the RhoA/ROCK1/2 pathway, which is involved in the regulation of actin cytoskeleton, was activated. On the other hand, we found that tolvaptan effectively inhibited cell proliferation, anchorage-independent growth, invasivity and promoted apoptosis. Accordingly, the RhoA/ROCK-1/2 pathway was inhibited.

CONCLUSIONS

These findings demonstrate for the first time that low [Na⁺] favours tumor progression in SCLC cells, whereas tolvaptan effectively inhibits cell proliferation, survival and invasivity.

USP52 inhibits cell proliferation by stabilizing PTEN protein in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the most common subtype of lung cancer. Ubiquitination is closely related to the development of lung cancer. However, the biological importance of newly discovered ubiquitin-specific peptidase (USP) 52 (USP52) in NSCLC remained unclear. Here, our findings identify USP52 as a novel tumor suppressor of NSCLC, the low expression of USP52 predicts a poor prognosis for NSCLC patients. The present study demonstrates that USP52 inhibits cancer cell proliferation through down-regulation of cyclin D1 (CCND1) as well as AKT/mTOR signaling pathway inhibition. Meanwhile, USP25 also suppresses NSCLC progression via enhancing phosphatase and tensin homolog (PTEN) stability in cancer cells, which further indicates the significance/importance of USP52 in NSCLC suppression.

Identification of Significant Genes in Lung Cancer of Nonsmoking Women via Bioinformatics Analysis

Background

The aim of this study was to identify potential key genes, proteins, and associated interaction networks for the development of lung cancer in nonsmoking women through a bioinformatics approach.

Methods

We used the GSE19804 dataset, which includes 60 lung cancer and corresponding paracancerous tissue samples from nonsmoking women, to perform the work. The GSE19804 microarray was downloaded from the GEO database and differentially expressed genes were identified using the limma package analysis in R software, with the screening criteria of p value < 0.01 and ∣log₂ fold change (FC) | >2.

Results

A total of 169 DEGs including 130 upregulated genes and 39 downregulated were selected. Gene Ontology and KEGG pathway analysis were performed using the DAVID website, and protein-protein interaction (PPI) networks were constructed and the hub gene module was screened through STING and Cytoscape.

Conclusions

We obtained five key genes such as GREM1, MMP11, SPP1, FOSB, and IL33 which were strongly associated with lung cancer in nonsmoking women, which improved understanding and could serve as new therapeutic targets, but their functionality needs further experimental verification.

Etomidate inhibits cell proliferation and induces apoptosis in A549 non-small cell lung cancer cells via downregulating WWP2

Etomidate (ETO) is a commonly used intravenous anesthetic that has been reported to exert a tumor suppressive effect in several types of cancer. The present study aimed to investigate the effect of ETO on cell proliferation and apoptosis in non-small cell lung cancer (NSCLC) cells and elucidate its potential mechanism of action. Therefore, Cell Counting Kit-8 assay was performed to evaluate the effect of different concentrations of ETO (0, 1, 2 or 3 µg/ml) on A549 cell viability. In addition, the possible interaction between ETO and WW domain containing E3 ubiquitin protein ligase 2 (WWP2) was predicted using the STITCH database. Additionally, a stable WWP2-overexpressing A549 cell line was constructed by transfecting A549 cells with the pcDNA3.1-WWP2 plasmid. Cell proliferation and apoptosis were assessed using colony formation and TUNEL assays, respectively. The mRNA and protein expression levels of the apoptosis-related proteins Bcl-2, Bax, caspase 3 and cleaved-caspase 3 were determined by reverse transcription-quantitative PCR and western blotting. In addition, the expression and phosphorylation levels of proliferation-associated genes (PCNA and Ki-67) and proteins in the PI3K/Akt pathway were analyzed by western blotting. The results showed that treatment with ETO attenuated the cell viability and proliferation of A549 cells. ETO also promoted cell apoptosis and decreased the expression of the anti-apoptotic protein Bcl-2, whilst increasing that of pro-apoptotic proteins Bax and cleaved caspase 3 in a dose-dependent manner. Furthermore, ETO was found to negatively regulate the expression of WWP2, such that WWP2 overexpression reversed the potentiating effects of ETO on cell apoptosis. In addition, ETO promoted the expression of PTEN and reduced the phosphorylation levels of the PI3K/AKT pathway-related proteins. These effects aforementioned could also be reversed by WWP2 overexpression. Therefore, data from the present study suggest that ETO can attenuate the progression of NSCLC through by the PI3K/AKT pathway, specifically by targeting WWP2. These findings may provide a novel target for the treatment of NSCLC.

ALKBH5 promotes cadmium-induced transformation of human bronchial epithelial cells by regulating PTEN expression in an m6A-dependent manner

Cadmium is a carcinogenic heavy metal that poses a severe threat to human beings. The underlying mechanism, however, remains elusive. N6-methyladenosine (m6A) is the most abundant post-transcriptional modification in mRNA that regulates RNA metabolism. Emerging evidence shows that m6A is involved in the pathogenesis of various cancers. In this study, human bronchial epithelial BEAS-2B cells were transformed by exposing to 2 μM of cadmium for 20 weeks to investigate the role of m6A in cadmium carcinogenesis. We found the level of m6A in mRNA was significantly decreased in cadmium-transformed BEAS-2B cells, and this change was regulated by m6A demethylase ALKBH5. ALKBH5 was significantly upregulated in the middle and late stages of cell transformation at week 8, 12, 16 and 20. Knockdown of ALKBH5 in cadmium-transformed cells alleviated cell proliferation, migration, invasion, and anchorage-independent growth, but co-transfection with ALKBH5 siRNA and PTEN siRNA restored the inhibitory effects of ALKBH5 knockdown on those transformation properties. ALKBH5 decreased the m6A level of PTEN mRNA, resulting in its instability and reduction of PTEN protein expression. These results indicate that ALKBH5-mediated demethylation m6A at PTEN mRNA is involved in cadmium-induced cell transformation. Our study provides a new perspective for the involvement of m6A modification in cadmium carcinogenesis.

PTEN loss promotes oncogenic function of STMN1 via PI3K/AKT pathway in lung cancer

Among all cancer types, lung cancer has already become the leading cause of cancer-related death around the world. The molecular mechanism understanding this development is still needed to be improved to treat lung cancer. Stathmin (STMN1) was initially identified as a cytoplasmic protein phosphorylated responding to cell signal and controlled cell physiological processes. The dysregulation of STMN1 is found in various kinds of tumors. However, the molecular mechanism of STMN1 regulating lung cancer is still unclear. Here, we found that STMN1 was overexpressed in lung cancer tissues and associated with worse survival rates of lung cancer patients. Inhibition of STMN1 suppressed lung cancer cell growth, migration and invasion, and promoted drug sensitivity. Moreover, PTEN loss promoted STMN1 expression via PI3K/AKT pathway. PTEN loss ameliorated the inhibition of cell growth, migration and invasion, and drug sensitivity induced by STMN1 knockdown in lung cancer. The high expression of STMN1 was negatively correlated with the low expression of PTEN in lung cancer specimens. Overall, our work demonstrated that PTEN regulated the oncogenic function of STMN1 in lung cancer.

Identification of MX2 as a Novel Prognostic Biomarker for Sunitinib Resistance in Clear Cell Renal Cell Carcinoma

Background

Antiangiogenic agents that specifically target vascular endothelial growth factor receptor (VEGFR), such as sunitinib, have been utilized as the standard therapy for metastatic clear cell renal cell carcinoma (ccRCC) patients. However, most patients eventually show no responses to the targeted drugs, and the mechanisms for the resistance remain unclear. This study is aimed to identify pivotal molecules and to uncover their potential functions involved in this adverse event in ccRCC treatment.

Methods

Two datasets, GSE64052 and GSE76068, were obtained from the Gene Expression Omnibus (GEO) database. The differentially expressed genes (DEGs) were identified using the limma package in R software. The gene set enrichment analysis (GSEA) was conducted using clusterProfiler package. A protein-protein interaction (PPI) network was built using the STRING database and Cytoscape software. Kaplan-Meier survival curves were plotted using R software. qRT-PCR and Western blotting were used to detect the MX2 and pathway expression in RCC cell lines. Sunitinib-resistant cell lines were constructed, and loss-of-function experiments were conducted by knocking down MX2. All statistical analyses were performed using R version 3.6.1 and SPSS 23.0.

Results

A total of 760 DEGs were derived from two datasets in GEO database, and five hub genes were identified, among which high-level MX2 exhibited a pronounced correlation with poor overall survival (OS) in sunitinib-resistant ccRCC patients. Clinical correlation analysis and Gene Set Variation Analysis (GSVA) on MX2 showed that the upregulation of MX2 was significantly related to the malignant phenotype of ccRCC, and it was involved in several pathways and biological processes associated with anticancer drug resistance. qRT-PCR and Western blotting revealed that MX2 was distinctly upregulated in sunitinib-resistant RCC cell lines. Colony formation assay and Cell Counting Kit-8 (CCK8) assay showed that MX2 strongly promoted resistant capability to sunitinib of ccRCC cells.

Conclusion

MX2 is a potent indicator for sunitinib resistance and a therapeutic target in ccRCC patients.

MicroRNA-103a-3p Promotes Cell Proliferation and Invasion in Non-Small-Cell Lung Cancer Cells through Akt Pathway by Targeting PTEN

Background

Increasing evidence has suggested that microRNA- (miR-) 103a-3p is crucial for cancer progression. However, the specific mechanism of miR-103a-3p in non-small-cell lung cancer (NSCLC) remains unclear until now. So, it is particularly urgent to clarify the mechanism between them.

Methods

qRT-PCR and western blot were used to measure the expression of miR-103a-3p, PTEN, Akt, and p-Akt. Cell biology experiment was applied to detect the biological function of miR-103a-3p in NSCLC cell lines. Moreover, bioinformatics analysis, luciferase reporter assay, and functional complementation analysis were carried out to investigate the target gene.

Results

miR-103a-3p was highly expressed in primary NSCLC samples and cell lines. miR-103a-3p mimics promoted the proliferation and invasion of NSCLC cells; miR-103a-3p inhibitor had the opposite effect. A double luciferase reporter gene experiment revealed that miR-103a-3p directly targets the PTEN mRNA 3'UTR region. siPTEN inhibited the proliferation and invasion of NSCLC cells. Further mechanistic studies showed that both overexpression of miR-103a-3p and PTEN knockdown reduced the expression of the p-Akt protein. Overexpression of PTEN partially reversed the cancer-promoting effect of miR-103a-3p.

Conclusion

miR-103a-3p promotes the progression of NSCLC via Akt signaling by targeting PTEN, highlighting the role of miR-103a-3p/PTEN/Akt signaling and suggesting miR-103a-3p as a novel therapeutic target for NSCLC.

Targeting therapy-resistant lung cancer stem cells via disruption of the AKT/TSPYL5/PTEN positive-feedback loop

Cancer stem cells (CSCs) are regarded as essential targets to overcome tumor progression and therapeutic resistance; however, practical targeting approaches are limited. Here, we identify testis-specific Y-like protein 5 (TSPYL5) as an upstream regulator of CSC-associated genes in non-small cell lung cancer cells, and suggest as a therapeutic target for CSC elimination. TSPYL5 elevation is driven by AKT-dependent TSPYL5 phosphorylation at threonine-120 and stabilization via inhibiting its ubiquitination. TSPYL5-pT120 also induces nuclear translocation and functions as a transcriptional activator of CSC-associated genes, ALDH1 and CD44. Also, nuclear TSPYL5 suppresses the transcription of PTEN, a negative regulator of PI3K signaling. TSPYL5-pT120 maintains persistent CSC-like characteristics via transcriptional activation of CSC-associated genes and a positive feedback loop consisting of AKT/TSPYL5/PTEN signaling pathway. Accordingly, elimination of TSPYL5 by inhibiting TSPYL5-pT120 can block aberrant AKT/TSPYL5/PTEN cyclic signaling and TSPYL5-mediated cancer stemness regulation. Our study suggests TSPYL5 be an effective target for therapy-resistant cancer.

In order to assist the development of cancer stem cell (CSC) therapy, Kim et al identified testis-specific Y-like protein 5 (TSPYL5) as an upstream regulator of CSC-associated genes in non-small cell lung cancer cells. They demonstrated in cancer cell lines and in vivo that TSPYL5 activity is dependent on AKT signalling and that disruption of TSPYL5 signalling could serve as a potential strategy to tackle therapy-resistant cancers.

LINC01559 promotes colorectal cancer via sponging miR-1343-3p to modulate PARP1/PTEN/AKT pathway

BACKGROUND

Colorectal cancer (CRC) is considered as one of the commonest tumors and is the major reason of cancer-related deaths around the world. Plentiful evidences have validated that long non-coding RNAs (lncRNAs) play a significant part in various cancers, including CRC. LINC01559 is implicated in the development of various cancers. However, the detailed function of LINC01559 in CRC has not been illustrated.

METHODS

LINC01559 expression was examined via RT-qPCR, and a series of functional experiments were conducted to explore the role of LINC01559 in CRC progression. Mechanism experiments were carried out to examine the underlying mechanism of LINC01559.

RESULTS

LINC01559 expression was increased in CRC cells and tissues, and LINC01559 depletion restrained the biological behaviors of CRC cells. Also, LINC01559 sponged miR-1343-3p in CRC, and PARP1 was the target of miR-1343-3p. Besides, miR-1343-3p overexpression or PARP1 down-regulation affected the biological behaviors of CRC cells. In addition, up-regulation of PARP1 or adding SC79 (AKT pathway activator) could remedy the repressive effects of LINC01559 silencing on CRC cell biological behaviors.

CONCLUSIONS

LINC01559 promotes CRC through sponging miR-1343-3p to modulate PARP1/PTEN/AKT pathway, which may be conducive to offering a new idea for CRC therapeutic treatment.

A novel evodiamine amino derivative as a PI3K/AKT signaling pathway modulator that induces apoptosis in small cell lung cancer cells

Evodiamine (EVO) was derivatized to a C10-amino derivative (EVA) using a two-step method suitable for industrializing production. This method has advantages such as a short reaction time, high yield, few byproducts and simple purification. The AUC and C_max values of EVA were 7.02- and 4.62-fold, while the T_max and Cl values were one-half and one-eighth that of EVO, respectively. EVA markedly improved the bioavailability, which might be ascribed to the serum albumin deposit effect. EVA was bound to albumin in the same hydrophobic pocket as EVO, but one more hydrogen bond was formed between Asp323 and the amino group at the C10 position. The amino derivative of natural alkaloids showed a substantial increase in antitumor activity on small cell lung cancer (SCLC) cells. The role of the PI3K/AKT signaling pathway in alkaloid/derivative-induced apoptosis in tumor cells was thoroughly described. p-AKT, its downstream effectors Bcl-2, Bax, caspase-3 and its upstream regulator PTEN were regulated by EVA. The interaction between EVO/EVA and the upstream protein PI3K p110 was first investigated with molecular docking. The apoptosis induced by EVA was abrogated after the PI3K/AKT signaling pathway was reactivated by IGF-1. The interaction between EVO/EVA and P-gp was also first studied using docking method. Their binding forces were weak. But EVA might reduce much expression of P-gp than EVO, and ultimately led to reduction of EVA efflux. Our study provides novel insights into a feasible and productive amino derivative of natural alkaloids for SCLC therapy.

Irreversible epidermal growth factor receptor inhibitor Z25h exhibits pronounced inhibition on non-small cell lung adenocarcinoma cell line Hcc827

The epidermal growth factor receptor (EGFR) signaling is frequently activated in lung cancer. In our previous study, a new class of compounds containing pyrido[3,4-d]pyrimidine scaffold with an acrylamide moiety was designed as irreversible EGFR-tyrosine kinase inhibitors to overcome acquired EGFR-T790M resistance. In this study, we selected the most promising compound Z25h to further investigate its effects and the underlying mechanism against non-small cell lung adenocarcinoma cells in vitro. Four different non-small cell lung adenocarcinoma cell lines were selected to test the antiviability profile of Z25h, and Hcc827 was the most sensitive to the drug treatment. Z25h caused cell cycle arrest at G0-G1 phase, and triggered strong early apoptosis in Hcc827 cells at 0.1 μM and late apoptosis in A549, H1975 and H1299 cells at 10 μM by 48 h treatment. Z25h inhibited the activation of EGFR and its downstream PI3K/AKT/mTOR pathway in the four tested cell lines, leading to the inhibition of cellular biosynthetic and metabolic processes and the promotion of apoptotic process. However, the effect of Z25h on mitogen-activated protein kinase pathway varies from cell lines. In addition, Z25h sensitized H1975 cells to X-ray radiation, and it also enhanced the radiation effect on A549 cells, while no obvious effect of Z25h was observed on the cell viability inhibition of H1299 cells induced by radiation. Hereby, Z25h might be considered as a potential therapeutic drug candidate for non-small cell lung adenocarcinoma treatment.

Inhibitory Effect of Immunologically Activated Mesenchymal Stem Cells on Lung Cancer Cell Growth and Metastasis

Background: Mesenchymal stem cells (MSCs) could inhibit the proliferation of lung cancer cells. The authors' study aimed to investigate the effects of immunologically activated human umbilical cord (HUC)-MSCs on A549 lung cancer cells. Materials and Methods: HUC-MSCs were separated from the umbilical cord using the adherence method. Surface markers of HUC-MSCs were detected by flow cytometry for MSC identification. Imiquimod (TLR7 agonist) was incubated with HUC-MSCs for immune activation, and the expression of MSC-specific markers and immune inflammatory molecules was measured by quantitative real-time polymerase chain reaction. HUC A549 cells were cocultured with HUC-MSCs treated with imiquimod, siTLR7 (small interfering RNA for TLR7) or TLR7 overexpression, and then cell viability, proliferation, migration, and invasion, and the expression of phosphatidylinositol-3-kinase (PI3K)/Akt and NF-κB was investigated using MTT assay, clone formation assay, transwell assay, and western blot, respectively. Results: HUC-MSCs were identified as positive for CD73, CD105, CD44, CD29, and CD90. Expression of MSC markers was inhibited, while those of immune inflammatory molecules expression except IL-6 (interleukin-6) was enhanced after MSCs were immunologically activated by imiquimod. After being cocultured with HUC-MSCs treated with imiquimod or overexpressed TLR7, cell viability, proliferation, and metastasis, and the phosphorylation of P65 and AKT in A549 cells were decreased, but apoptosis was increased, while siTLR7 showed the opposite effect HUC. Conclusions: Immunologically activated HUC-MSCs inhibited the growth and metastasis, yet, promoted the apoptosis of A549 lung cancer cells via regulating the PI3K/Akt and NF-κB pathways.

Metformin attenuates synergic effect of diabetes mellitus and Helicobacter pylori infection on gastric cancer cells proliferation by suppressing PTEN expression

It has been reported that CagA of Helicobacter pylori reduced PTEN expression by enhancing its promoter methylation. Furthermore, diabetes mellitus (DM) may also promote the methylation status of PTEN, a tumour suppressor gene in gastric cancer (GC). It is intriguing to explore whether DM may strengthen the tumorigenic effect of H pylori (HP) by promoting the methylation of PTEN promoter and whether the administration of metformin may reduce the risk of GC by suppressing the methylation of PTEN promoter. In this study, we enrolled 107 GC patients and grouped them as HP(-)DM(-) group, HP(+)DM(-) group and HP(+)DM(+) group. Bisulphite sequencing PCR evaluated methylation of PTEN promoter. Quantitative real-time PCR, immunohistochemistry and Western blot, immunofluorescence, flow cytometry and MTT assay were performed accordingly. DNA methylation of PTEN promoter was synergistically enhanced in HP(+)DM(+) patients, and the expression of PTEN was suppressed in HP(+)DM(+) patients. Cell apoptosis was decreased in HP(+)DM(+) group. Metformin showed an apparent effect on restoring CagA-induced elevation of PTEN promoter methylation, thus attenuating the PTEN expression. The reduced PTEN level led to increased proliferation and inhibited apoptosis of HGC-27 cells. In this study, we collected GC tumour tissues from GC patients with or without DM/HP to compare their PTEN methylation and expression while testing the effect of metformin on the methylation of PTEN promoter. In summary, our study suggested that DM could strengthen the tumorigenic effect of HP by promoting the PTEN promoter methylation, while metformin reduces GC risk by suppressing PTEN promoter methylation.

The Association of microRNA-34a With High Incidence and Metastasis of Lung Cancer in Gejiu and Xuanwei Yunnan

The incidence and associated mortality of lung cancer in tin miners in Gejiu County and farmers in Xuanwei Country, Yunnan Province have been very high in the world. Current published literatures on the molecular mechanisms of lung cancer initiation and progression in Gejiu and Xuanwei County are still controversial. Studies confirmed that microRNA-34a (miR-34a) functioned as a vital tumor suppressor in tumorigenesis and progression. However, the role and precise mechanisms of miR-34a and its regulatory gene network in initiation and progression of lung cancer in Gejiu and Xuanwei County, Yunnan Province, have not been elucidated. In the current study, we first found that miR-34a was downregulated in Gejiu lung squamous carcinoma YTMLC-90, Xuanwei lung adenocarcinoma XWLC-05, and other non-small cell lung carcinoma (NSCLC) cell lines, and miR-34a overexpression inhibited cell proliferation, migration and invasion, as well as induced cell apoptosis in YTMLC-90 and XWLC-05 cells. Our findings revealed that miR-34a is critical and cannot be considered as the area-specific non-coding RNA in initiation and progression of lung cancer in Gejiu and Xuanwei County. Next we revealed that miR-34a overexpression suppressed lung cancer growth and metastasis partially via increasing PTEN but reducing CDK6 expression that might lead to subsequent inactivation of PI3K/AKT pathway. Furthermore, our findings demonstrated that YY1 functioned as a tumor suppressor gene in initiation and progression of lung cancer in Gejiu and Xuanwei County. In conclusion, our findings in the study confirmed that miR-34a overexpression could simultaneously suppress tumor growth and metastasis and play a vital role in tumorigenesis and progression of NSCLC via increasing PTEN and YY1 expression, but decreasing CDK6. Most interestingly, our findings also raised doubts about the current ideas about these area-specific diseases.

Glycogen Synthase Kinase-3 Beta Expression Correlates With Worse Overall Survival in Non-Small Cell Lung Cancer-A Clinicopathological Series

Background

Glycogen Synthase Kinase-3 beta (GSK-3β) regulates diverse cell functions including metabolic activity, signaling and structural proteins. GSK-3β phosphorylates target pro-oncogenes and regulates programmed cell death-ligand 1 (PD-L1). This study investigated the correlation between GSK-3β expression and clinically relevant molecular features of lung adenocarcinoma (PDL1 score, PTEN expression and driver mutations).

Methods

We evaluated 95 lung cancer specimens from biopsies and surgical resections. Immunohistochemistry was performed to analyze the expression of GSK-3β, PTEN, and PDL1. Epidemiological data, molecular characteristics and staging were evaluated from medical records. The histologic classification was performed by an experienced pulmonary pathologist.

Results

Most patients were female (52.6%) and the majority had a positive smoking history. The median age was 68.3 years, with individuals over 60 years accounting for 82.1%. The predominant histological subtype was adenocarcinoma (69.5%), followed by squamous cell carcinoma (20.0%). GSK-3β expression in tumors was cytoplasmic with a dotted pattern and perinuclear concentration, with associated membranous staining. Seven (7.3%) tumors had associated nuclear expression localization. Seventy-seven patients (81.1%) had advanced clinical-stage tumors. GSK-3β was positive in 75 tumors (78%) and GSK3-positive tumors tended to be diagnosed at advanced stages. Among stage III/IV tumors, 84% showed GSK3 positivity (p= 0.007). We identified a statistically significant association between GSK-3β and PTEN in the qualitative analysis (p 0.021); and when comparing PTEN to GSK-3β intensity 2+ (p 0.001) or 3+ expression (> 50%) – p 0.013. GSK-3β positive tumors with a high histological score had a worse overall survival.

Conclusion

We identified the histological patterns of GSK-3β expression and evaluated its potential as marker for overall survival, establishing a simple histological score to measure the evaluated status in resected tissues. The use of GSK-3β expression as an immune response biomarker remains a challenge. Future studies will seek to explain the role of its interaction with PTEN.

The double-edged roles of ROS in cancer prevention and therapy

Reactive oxygen species (ROS) serve as cell signaling molecules generated in oxidative metabolism and are associated with a number of human diseases. The reprogramming of redox metabolism induces abnormal accumulation of ROS in cancer cells. It has been widely accepted that ROS play opposite roles in tumor growth, metastasis and apoptosis according to their different distributions, concentrations and durations in specific subcellular structures. These double-edged roles in cancer progression include the ROS-dependent malignant transformation and the oxidative stress-induced cell death. In this review, we summarize the notable literatures on ROS generation and scavenging, and discuss the related signal transduction networks and corresponding anticancer therapies. There is no doubt that an improved understanding of the sophisticated mechanism of redox biology is imperative to conquer cancer.

Epigallocatechin Gallate Protects against MNNG-Induced Precancerous Lesions of Gastric Carcinoma in Rats via PI3K/Akt/mTOR Pathway

Objective

To evaluate the therapeutic effect of epigallocatechin gallate (EGCG) on precancerous lesions of gastric carcinoma (PLGC) and to determine whether EGCG protects against PLGC by regulating PI3K/Akt/mTOR pathway.

Methods

Twenty-four male Wistar rats were randomly divided into 3 groups: normal control group (NC), PLGC model group (MC), and group of PLGC rats treated with EGCG (MC + EGCG). 1-Methyl-3-nitro-1-nitrosoguanidine (MNNG) and sodium salicylate were combined and used to establish the PLGC rat animal model. The therapeutic effect of EGCG on PLGC was evaluated by body weight and pathological lesions of gastric mucosa in PLGC rats. Quantitative polymerase chain reaction (qPCR) was applied to measure the mRNA expressions of PI3K, Akt, and mTOR. The protein expressions of cleaved caspase-3, PTEN, PI3K, p-PI3K, Akt, p-Akt, p-mTOR, and mTOR were determined by automated western immunoblotting.

Results

The body weight decreased in PLGC rats while EGCG significantly increased body weight. The gastric mucosa of PLGC rats exhibited the pathological lesions of atrophy, intestinal metaplasia, and atypical hyperplasia while EGCG could ameliorate the pathological lesions. EGCG could upregulate the expressions of cleaved caspase-3 and PTEN and reduce the expressions of PI3K, Akt, and mTOR.

Conclusions

EGCG ameliorated pathological lesions of PLGC and exerted the effect of apoptosis promotion in PLGC rats. The apoptotic pathway triggered by EGCG may be related to inhibition of PI3K/Akt/mTOR pathway. It provided a theoretical basis for the PLGC treatment and gastric cancer prevention.

Computational Analysis of Drug Resistance Network in Lung Adenocarcinoma

BACKGROUND

Lung cancer is a significant health problem and accounts for one-third of the deaths worldwide. A great majority of these deaths are caused by non-small cell lung cancer (NSCLC). Chemotherapy is the leading treatment method for NSCLC, but resistance to chemotherapeutics is an important limiting factor that reduces the treatment success of patients with NSCLC.

OBJECTIVE

In this study, the relationship between differentially expressed genes affecting the survival of the patients, according to the bioinformatics analyses, and the mechanism of drug resistance is investigated for non-small cell lung adenocarcinoma patients.

METHODS

Five hundred thirteen patient samples were compared with fifty-nine control samples. The employed dataset was downloaded from The Cancer Genome Atlas (TCGA) database. The information on how the drug activity altered against the expressional diversification of the genes was extracted from the NCI-60 database. Four hundred thirty-three drugs with known mechanism of action (MoA) were analyzed. Diversifications of the activity of these drugs related to genes were considered based on nine lung cancer cell lines virtually. The analyses were performed using R programming language, GDCRNATools, rcellminer, and Cytoscape.

RESULTS

This work analyzed the common signaling pathways and expressional alterations of the proteins in these pathways associated with survival and drug resistance in lung adenocarcinoma. Deduced computational data demonstrated that proteins of EGFR, JNK/MAPK, NF-κB, PI3K /AKT/mTOR, JAK/STAT, and Wnt signaling pathways were associated with molecular mechanism of resistance to anticancer drugs in NSCLC cells.

CONCLUSION

To understand the relationships between resistance to anticancer drugs and EGFR, JNK/MAPK, NF-κB, PI3K /AKT/mTOR, JAK/STAT, and Wnt signaling pathways is an important approach to design effective therapeutics for individuals with NSCLC adenocarcinoma.

PTEN Loss as a Predictor of Tumor Heterogeneity and Poor Prognosis in Patients With EGFR-mutant Advanced Non-small-cell Lung Cancer Receiving Tyrosine Kinase Inhibitors

BACKGROUND

Rapid disease progression of patients with advanced epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer (NSCLC) has been recently associated with tumor heterogeneity, which may be mirrored by coexisting concomitant alterations. The aim of this analysis was to investigate the correlation between loss of function of PTEN and the efficacy of tyrosine kinase inhibitors in this population.

MATERIALS AND METHODS

Archival tumor blocks from patients with EGFR-mutant NSCLC who were administered upfront tyrosine kinase inhibitors were retrospectively collected. The status of 4 genes (PTEN, TP53, c-MET, IGFR) was evaluated by immunohistochemistry, and it was correlated with overall response rate, overall survival (OS), and progression-free survival (PFS).

RESULTS

Fifty-one patients were included. In multivariate analysis, PTEN loss (hazard ratio [HR], 3.46; 95% confidence interval [CI], 1.56-7.66; P = .002), IGFR overexpression (HR, 2.22; 95% CI, 1.03-4.77; P = .04), liver metastases (HR, 3.55; 95% CI, 1.46-8.65; P = .005), and Eastern Cooperative Oncology Group performance status (ECOG PS) ≥ 1 (HR, 2.57; 95% CI, 1.04-6.34; P = .04) were significantly associated with shorter PFS. Patients with PTEN loss had a median PFS of 6 months (2-year PFS, 11.6%), whereas patients without PTEN loss had a median PFS of 18 months (2-year PFS, 43.6%) (log-rank P < .005). In the multivariate analysis, PTEN loss (HR, 5.92; 95% CI, 2.37-14.81; P < .005), liver metastases (HR, 2.63; 95% CI, 1.06-6.51; P = .037), and ECOG PS ≥ 1 (HR, 2.80; 95% CI, 1.15-6.81; P = .024) were significantly associated with shorter OS. Patients with PTEN loss had a median OS of 6 months (2-year OS, 12.2%), whereas in patients without PTEN loss, OS was not reached (2-year OS, 63.9%) (log-rank P < .0005).

CONCLUSIONS

A low-cost and reproducible immunohistochemistry assay for PTEN loss analysis represents a potential tool for identifying tumor heterogeneity in patients with advanced EGFR-mutant NSCLC.

Long non‑coding RNA MEG3 inhibits cell migration and invasion of non‑small cell lung cancer cells by regulating the miR‑21‑5p/PTEN axis

Long non-coding RNAs (lncRNAs) are involved in the occurrence and progression of numerous types of cancer. The aim of the present study was to evaluate the effect of the lncRNA maternally expressed gene 3 (MEG3) on the migration and invasion of non-small cell lung cancer (NSCLC) H1299 and PC9 cells. Reverse transcription-quantitative (RT-q)PCR analysis showed that MEG3 was downregulated in NSCLC PC9 and H1299 cells. Additionally, bioinformatics analysis indicated that MEG3 sponges microRNA (miR)-21-5p; miR-21-5p was predicted to target the phosphatase and tensin homolog (PTEN) 3′-untranslated region sequence. MEG3 overexpression led to miR-21-5p suppression and PTEN upregulation in PC9 and H1299 cells, as detected by RT-qPCR. Subsequently, western blot analysis confirmed that MEG3 overexpression enhanced PTEN expression levels and inhibited the PI3K/AKT signaling pathway in NSCLC cells. These effects were attenuated by miR-21-5p. Dual luciferase assay supported the sponging effect of MEG3 on miR-21-5p and validated the direct interaction between miR-21-5p and PTEN. Furthermore, Transwell assay demonstrated that MEG3 overexpression had an inhibitory effect on cell migration and invasion. MEG3 overexpression also mediated epithelial-to-mesenchymal transition by significantly enhancing E-cadherin and decreasing N-cadherin, Vimentin and matrix metalloprotein 9 expression levels in NSCLC cells, as indicated by western blot analysis. These changes were partially reversed by an miR-21-5p mimic. These results indicated that MEG3 acted as a tumor suppressor that inhibited NSCLC cell migration and invasion via sponging miR-21-5p, which, in turn, enhanced the expression levels of PTEN, in part via the PI3K/AKT signaling pathway. The results of the present study have suggested the potential of MEG3 as a novel therapeutic target for NSCLC treatment.

PCGF3 promotes the proliferation and migration of non-small cell lung cancer cells via the PI3K/AKT signaling pathway

The Polycomb Group Ring Finger 3 (PCGF3) protein has been reported to be significantly upregulated in pancreatic islet tumors and related to signal transduction; however, its detailed mechanisms and biological roles in other tumors, including non-small cell lung cancer (NSCLC), remain unclear. This study investigated the function of PCGF3 in NSCLC and further elucidated its mechanism of action. The immunohistochemical analysis of 86 selected lung cancer tissues revealed that PCGF3 was highly expressed in NSCLC tissues and positively correlated with lymph node metastasis and p-TNM staging. Additionally, PCGF3 promoted cell proliferation in lung cancer by regulating CyclinB1, CyclinD1, and CDK4 expression, and also promoting their migration by regulating RhoA, RhoC, and CDC42. Furthermore, PCGF3 affected both the proliferation and migration of lung cancer cells by regulating the PI3K/AKT pathway, as verified by inhibiting this pathway using LY294002. The findings of this study suggested that PCGF3 is associated with poor prognosis in patients with NSCLC and could therefore be an important biomarker for treating and preventing NSCLC.

RNA splicing and aggregate gene expression differences in lung squamous cell carcinoma between patients of West African and European ancestry

OBJECTIVES

Despite disparities in lung cancer incidence and mortality, the molecular landscape of lung cancer in patients of African ancestry remains underexplored, and race-related differences in RNA splicing remain unexplored.

MATERIALS AND METHODS

We identified differentially spliced genes (DSGs) and differentially expressed genes (DEGs) in biobanked lung squamous cell carcinoma (LUSC) between patients of West African and European ancestry, using ancestral genotyping and Affymetrix Clariom D array. DSGs and DEGs were validated independently using the National Cancer Institute Genomic Data Commons. Associated biological processes, overlapping canonical pathways, enriched gene sets, and cancer relevance were identified using Gene Ontology Consortium, Ingenuity Pathway Analysis, Gene Set Enrichment Analysis, and CancerMine, respectively. Association with LUSC survival was conducted using The Cancer Genome Atlas.

RESULTS

4,829 DSGs and 267 DEGs were identified, including novel targets in NSCLC as well as genes identified previously to have relevance to NSCLC. RNA splicing events within 3 DSGs as well as 1 DEG were validated in the independent cohort. 853 DSGs and 29 DEGs have been implicated as potential drivers, oncogenes and/or tumor suppressor genes. Biological processes enriched among DSGs and DEGs included metabolic process, biological regulation, and multicellular organismal process and, among DSGs, ion transport. Overlapping canonical pathways among DSGs included neuronal signaling pathways and, among DEGs, cell metabolism involving biosynthesis. Gene sets enriched among DSGs included KRAS Signaling, UV Response, E2 F Targets, Glycolysis, and Coagulation. 355 RNA splicing events within DSGs and 18 DEGs show potential association with LUSC patient survival.

CONCLUSION

These DSGs and DEGs, which show potential biological and clinical relevance, could have the ability to drive novel biomarker and therapeutic development to mitigate LUSC disparities.

Lnc-GAN1 expression is associated with good survival and suppresses tumor progression by sponging mir-26a-5p to activate PTEN signaling in non-small cell lung cancer

BACKGROUND

Long non-coding RNAs (lncRNAs) play vital roles in the development and progression of non-small-cell lung cancer (NSCLC); however, the role of most lncRNAs in NSCLC remains unknown. This study explored the clinical significance, biological function and underlying mechanism of lnc-GAN1 in NSCLC.

METHODS

With a custom lncRNA microarray we found that lnc-GAN1 is markedly downregulated in NSCLC tissues. Then lnc-GAN1 expression level was measured using qRT-PCR in NSCLC tissues and cell lines. Survival was assessed using the Kaplan-Meier method. The biological functions of lnc-GAN1 in lung cancer cells were evaluated in vitro and in vivo. RNA fluorescence in situ hybridization and subcellular localization assays revealed the subcellular distribution of lnc-GAN1 in cells. Bioinformatic analysis was adopted to predict miRNAs and signaling pathways regulated by lnc-GAN1. RNA immunoprecipitation and Dual-luciferase reporter assays were used to assess the interaction between lnc-GAN1 and miR-26a-5p in lung cancer cells.

RESULTS

lnc-GAN1 is downregulated in HCC tissues and associated with larger tumor size and poor overall survival and disease-free survival; its ectopic expression suppresses cell proliferation, colony formation, and cell cycle progression and induces apoptosis in NSCLC cells; it also inhibits tumor growth in the NSCLC xenograft model. We further proved that lnc-GAN1 is localized in cytoplasm and transcribed independently from its parental gene GAN. Mechanistically, lnc-GAN1 acts as a sponge for miR-26a-5p by two seed sequences, and the two non-coding RNAs have a negative relationship in NSCLC tissues; we further prove that PTEN is a direct target of miR-26a-5p and lnc-GAN1 inhibits cell cycle signaling pathway by activating PTEN, whose expression level correlated negatively with miR-26a-5p level but positively with lnc-GAN1 level in NSCLC samples.

CONCLUSIONS

Lnc-GAN1 is downregulated and associated with poor survival of NSCLC patients, and mechanistically acts as a tumor suppressor via sponging and inhibiting miR-26a-5p to upregulate PTEN. This study provides a potential prognostic biomarker and treatment target for NSCLC.

MiR-508-3p promotes proliferation and inhibits apoptosis of middle ear cholesteatoma cells by targeting PTEN/PI3K/AKT pathway

Cholesteatoma of the middle ear is a common disease in otolaryngology, which can lead to serious intracranial and extracranial complications. Recent studies showed that the dysregulation of microRNA may be involved in the formation of middle ear cholesteatoma. This study aimed to explore the regulatory effect of micro ribonucleic acid 508-3p (miR-508-3p) on proliferation and apoptosis of middle ear cholesteatoma cells and excavate its underlying regulatory mechanism. We found miR-508-3p expression was upregulated in tissues and cells of cholesteatoma which was inversely related to the expression of hsa_circ_0000007. Overexpression of miR-508-3p could notably facilitate cholesteatoma cell proliferation. Luciferase reporter assay showed that miR-508-3p bound the 3'-untranslated region of its downstream mRNA PTEN. Gain and loss of functions of miR-508-3p were performed to identify their roles in the biological behaviors of cholesteatoma cells, including proliferation and apoptosis. Rescue assays confirmed that PTEN could reverse the effect of miR-508-3p overexpression on cell proliferation. In a word, this study validated that the development of cholesteatoma may regulated by hsa_circ_0000007/miR-508-3p/ PTEN/ PI3K/Akt axis.

Huaier shows anti-cancer activities by inhibition of cell growth, migration and energy metabolism in lung cancer through PI3K/AKT/HIF-1α pathway

Huaier has been verified to have anti-cancer effects on many tumours. However, little information is available about the effects of Huaier on non-small cell lung cancer (NSCLC). We sought to probe the anti-cancer effects and related mechanisms of Huaier on lung cancer. A549 cells were pre-treated with 2, 4 and 8 mg/mL Huaier at different time points. Thereafter, cell viability was analysed by CCK-8 and the migration and invasion were detected by Scratch test and Transwell chamber migration assay. Moreover, ELISA, Western blot, shRNA transfection and RT-PCR were conducted to discover the related gene and protein expressions of energy metabolism and phosphatidylinositol 3-kinase (PI3K)/AKT/hypoxia-inducible factor 1α (HIF-1α) pathway. Furthermore, tumour xenografts were accomplished to inspect the anti-cancer effects of Huaier. Our consequences suggested that Huaier considerably repressed cell viability and migration in a dose-dependent way. In addition, Huaier statistically suppressed glycolysis, glucose transport and lactic acid (LA) accumulation. Besides, we detected that Huaier could inactivate the PI3K/AKT/HIF-1α pathway. The in vivo data confirmed that Huaier obviously decreased tumour volume and tumour growth, reduced the glycolysis, glucose transport and HIF-1α expression in the tumour-bearing tissues. Our results suggested Huaier revealed anti-tumour effects in both in vivo and in vitro possibly through PI3K/AKT/HIF-1α pathway.

Concurrent Genetic Alterations and Other Biomarkers Predict Treatment Efficacy of EGFR-TKIs in EGFR-Mutant Non-Small Cell Lung Cancer: A Review

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) greatly improve the survival and quality of life of non-small cell lung cancer (NSCLC) patients with EGFR mutations. However, many patients exhibit de novo or primary/early resistance. In addition, patients who initially respond to EGFR-TKIs exhibit marked diversity in clinical outcomes. With the development of comprehensive genomic profiling, various mutations and concurrent (i.e., coexisting) genetic alterations have been discovered. Many studies have revealed that concurrent genetic alterations play an important role in the response and resistance of EGFR-mutant NSCLC to EGFR-TKIs. To optimize clinical outcomes, a better understanding of specific concurrent gene alterations and their impact on EGFR-TKI treatment efficacy is necessary. Further exploration of other biomarkers that can predict EGFR-TKI efficacy will help clinicians identify patients who may not respond to TKIs and allow them to choose appropriate treatment strategies. Here, we review the literature on specific gene alterations that coexist with EGFR mutations, including common alterations (intra-EGFR [on target] co-mutation, TP53, PIK3CA, and PTEN) and driver gene alterations (ALK, KRAS, ROS1, and MET). We also summarize data for other biomarkers (e.g., PD-L1 expression and BIM polymorphisms) associated with EGFR-TKI efficacy.

Germline variation networks in the PI3K/AKT pathway corresponding to familial high-incidence lung cancer pedigrees

Background

There were scarcely germline variants of familial lung cancer (LC) identified. We conducted an study with whole-exome sequencing of pedigrees with familial lung cancer to analyze the potential genetic susceptibility.

Methods

Probands with the highest hereditary background were identified by our large-scale epidemiological study and five ones were enrolled as a learning set. The germline SNPs (single-nucleotide polymorphisms) of other five similar probands, four healthy individuals in the formerly pedigrees and three patients with sporadic LC were used as a validation set, controlled by three healthy individuals without family history of any cancer. The network of mutated genes was generated using STRING-DB and visualized using Cytoscape.

Results

Specific and shared somatic mutations and germline SNPs were not the shared cause of familial lung cancer. However, individual germline SNPs showed distinct protein-protein interaction network patterns in probands versus healthy individuals and patients with sporadic lung cancer. SNP-containing genes were enriched in the PI3K/AKT pathway. These results were validated in the validation set. Furthermore, patients with familial lung cancer were distinguished by many germline variations in the PI3K/AKT pathway by a simple SVM classification method. It is worth emphasizing that one person with many germline variations in the PI3K/AKT pathway developed lung cancer during follow-up.

Conclusions

The phenomenon that the enrichments of germline SNPs in the PI3K/AKT pathway might be a major predictor of familial susceptibility to lung cancer.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-020-07528-3.

miRNA-26-5p inhibits cyclosporine A-induced overgrowth of gingival fibroblasts by regulating PTEN/PI3K/AKT pathway

We evaluated the effect of cyclosporine A (CsA) administration on the level of miR-26-5p in rat gingival tissues and human gingival fibroblasts (HGFs) by qRT-PCR assay. Further, we conducted Western blotting and immunohistochemical analysis to assess the expressions of PTEN, PI3K, and p-AKT, and evaluated cell proliferation of HGFs by MTT assay. CsA treatment significantly downregulated the expressions of miR-26-5p and PTEN and upregulated the expressions of PI3K and p-AKT in both rat gingival tissues and HGFs. Overexpression of miR-26-5p inhibited CsA-induced overgrowth of HGFs, whereas knockdown of miR-26-5p promoted the overgrowth. PTEN knockdown not only promoted CsA-induced overgrowth of human HGFs but also reversed the repressive effects of miR-26-5p on CsA-induced overgrowth of HGFs. Our results revealed that miRNA-26-5p could repress CsA-induced overgrowth of human HGFs by regulating PTEN/PI3K/AKT pathway.

GDC-0349 inhibits non-small cell lung cancer cell growth

Non-small cell lung cancer (NSCLC) is a leading cause of cancer-related human mortality with a clear need for new therapeutic intervention. GDC-0349 is a potent and selective ATP-competitive mTOR inhibitor. In A549 cells and primary human NSCLC cells, GDC-0349 inhibited cell growth, proliferation, cell cycle progression, migration and invasion, while inducing significant apoptosis activation. Although GDC-0349 blocked Akt-mTORC1/2 activation in NSCLC cells, it also exerted cytotoxicity in Akt1-knockout A549 cells. Furthermore, restoring Akt-mTOR activation by a constitutively-active Akt1 only partially attenuated GDC-0349-induced A549 cell apoptosis, indicating the existence of Akt-mTOR-independent mechanisms. In NSCLC cells GDC-0349 induced sphingosine kinase 1 (SphK1) inhibition, ceramide accumulation, JNK activation and oxidative injury. Conversely, N-acetylcysteine, the JNK inhibitor and sphingosine 1-phosphate alleviated GDC-0349-induced NSCLC cell apoptosis. In vivo, daily oral administration of GDC-0349 potently inhibited NSCLC xenograft growth in mice. Akt-mTOR in-activation, SphK1 inhibition, JNK activation and oxidative stress were detected in NSCLC xenograft tissues with GDC-0349 administration. In summary, GDC-0349 inhibits NSCLC cell growth via Akt-mTOR-dependent and Akt-mTOR-independent mechanisms.

SDF1/CXCR4 axis facilitates the angiogenesis via activating the PI3K/AKT pathway in degenerated discs

Symptomatic degenerative disc disease (DDD) is considered the leading cause of chronic lower back pain (LBP). As one of the main features of intervertebral disc degeneration (IDD), vascular ingrowth plays a crucial role in the progression of LBP. Stromal cell‑derived factor 1 (SDF1) and its receptor C‑X‑C receptor 4 (CXCR4) were reported to be overexpressed in the degenerated intervertebral discs, suggesting that they may be involved in the pathogenesis of IDD. Moreover, SDF1 has been identified to induce neovascularization in rheumatoid arthritis disease. However, the roles of the SDF1/CXCR4 axis in the neovascularization of IDD remain unclear. Therefore, the objective of the present study was to elucidate whether the SDF1/CXCR4 axis takes part in neovascularization in degenerated intervertebral discs and its underlying mechanisms. Adenovirus infection was used to upregulate SDF1 expression in primary nucleus pulposus cells (NPCs). The effects of SDF1 on the proliferation and angiogenesis of vascular endothelial cells (VECs) were assessed by Cell Counting Kit‑8 and tube formation assays after VECs were treated with the supernatants derived from SDF1 overexpressed or not treated NPCs. Transwell chambers using the supernatants from NPCs as chemokines were applied to assess VEC migration and invasion. AMD3100, MK‑2206 and SF1670 were used to antagonize CXCR4, AKT serine/threonine kinase 1 (AKT) and phosphatase and tensin homolog (PTEN) in VECs. The results revealed that SDF1 overexpression significantly increased the ratio of phosphorylated AKT to AKT and decreased PTEN expression in NPCs, as well as enhanced the proliferation, migration, invasion and angiogenesis abilities of VECs. However, these effects induced by SDF1 overexpression in NPCs were all reversed when VECs were pretreated with AMD3100 or MK‑2206, whereas enhanced by SF1670 treatment. Collectively, the present study indicated that enhancement of the SDF1/CXCR4 axis in NPCs can significantly accelerate angiogenesis by regulating the PTEN/phosphatidylinositol‑3‑kinase/AKT pathway.

miR-144-3p Contributes to the Development of Thyroid Tumors Through the PTEN/PI3K/AKT Pathway

Purpose

To explore the expression and related mechanism of miR-144-3p and PTEN in thyroid cancer (TC).

Patients and Methods

From February 2018 to November 2019, 62 patients with TC who received treatment in Chengwu Hospital Affiliated to Shandong First Medical University were collected. TC cells and human normal thyroid HTori-3 cells were purchased. The miR-144-3p-inhibitor, miR-144-3p-mimics, empty vector plasmid (miRNA-NC), si-PTEN and sh-PTEN were transfected into B-CPAP and HTh-7 cells. The expressions of miR-144-3p and PTEN in the specimens were tested by qRT-PCR (qP). WB was used to detect the expression of Bcl-2, APR3, N-cadherin, Slug and Bax proteins in the cells. The cell proliferation was detected by MTT, and the cell invasion was tested by Transwell. The apoptosis was detected by flow cytometry (FC).

Results

miR-144-3p was highly expressed and PTEN was weakly expressed in the patients’ tissues. The AUC of miR-144-3p and PTEN was >0.8. miR-144-3p and PTEN were related to TNM stage, lymph node metastasis and differentiation degree of TC patients. The B-CPAP and HTh-7 with the greatest expression differences were selected for transfection. The expression of miR-144-3p in miR-144-3p-inhibitor group was significantly lower than that in NC group (P<0.01), and that in miR-144-3p-mimics group was significantly higher than that in NC group (p < 0.01). The expression of PTEN in si-PTEN group was significantly lower than that in NC group (P<0.01), while that in sh-PTEN group was significantly higher than that in NC group (P<0.01). Silencing miR-144-3p and overexpressing PTEN could inhibit cell proliferation, invasion and promote apoptosis. WB detection uncovered that silencing the miR-144-3p expression and overexpressing PTEN could inhibit the PI3K, Akt, p-AKT, Bcl-2, APR3 and cyclinD1 proteins and promote the up-regulation of Bax expression. Rescue experiments revealed that the cell proliferation, invasion and apoptosis were not different from NC after co-transfection of miR-144-3p-mimics+sh-PTEN and miR-144-3p-inhibitor+si-PTEN into B-CPAP and HTh-7.

Conclusion

Inhibition of miR-144-3p expression can up-regulate PTEN and affect cell proliferation, invasion and apoptosis, which may be a potential therapeutic target for TC.

Mechanisms of tRNA-derived fragments and tRNA halves in cancer treatment resistance

The tRNA-derived fragments (tRFs) and tRNA halves (tiRNAs) are newly discovered noncoding RNAs in recent years. They are derived from specific cleavage of mature and pre-tRNAs and expressed in various cancers. They enhance cell proliferation and metastasis or inhibit cancer progression. Many studies have investigated their roles in the diagnosis, progression, metastasis, and prognosis of various cancers, but the mechanisms through which they are involved in resistance to cancer treatment are unclear. This review outlines the classification of tRFs and tiRNAs and their mechanisms in cancer drug resistance, thus providing new ideas for cancer treatment.

The Clinical Utility of miR-21 and let-7 in Non-small Cell Lung Cancer (NSCLC). A Systematic Review and Meta-Analysis

Non-small cell lung cancer (NSCLC) remains a problem worldwide due to its rapid progression and low rate of response to treatment. The heterogeneity of these tumors observed in histopathology exam but also in the mutational status and gene expression pattern makes this malignancy difficult to treat in clinic. The present study investigated the effect of miR-21 and let-7 family members as prognostic biomarkers in NSCLC patients based on the results published in different studies regarding this subject until March 2019. The analysis revealed that these two transcripts are steady biomarkers for prediction of patient outcome or survival. Upregulated expression of miR-21 is associated with poor outcome of patients with NSCLC [HR = 1.87, 95% CI = (1.41, 2.47), p < 0.001]. The analysis regarding let-7 family, specifically let-7a/b/e/f, revealed that downregulated expression of these transcripts predicts poor outcome for NSCLC patients [HR = 2.61, 95% CI = (1.58, 4.30), p < 0.001]. Besides, the reliability of these microRNAs is reflected in the fact that their prognostic significance is constant given the different sample types (tissue, FFPE tissue, serum, serum/plasma or exosomes) used in the selected studies.

Knockdown of circPRKCA Restrained Cell Growth, Migration, and Invasion of NSCLC Cells Both in vitro and in vivo via Regulating miR-330-5p/PDK1/AKT Pathway

Background

Protein kinase Cα (PRKCA) is an oncogene in multiple cancers including non-small-cell lung cancer (NSCLC) and can be transcribed into a number of circular PRKCAs (circPRKCAs). Here, we aimed to elaborate the role and mechanism of circPRKCA_024 (circPRKCA) in malignant progression of NSCLC.

Methods

Expression of circPRKCA, miRNA (miR)-330-5p and 3-phosphoinositide-dependent protein kinase-1 (PDK1) was measured by real-time quantitative PCR and Western blotting, and their relationship was testified by dual-luciferase reporter assay, RNA immunoprecipitation, and RNA pull-down assay. Cell behaviors were evaluated by cell counting kit (CCK)-8, flow cytometry, and transwell assays. AKT activity was confirmed by Western blotting. Xenograft experiment assessed tumor growth.

Results

Expression of circPRKCA and PDK1 was upregulated, and miR-330-5p was downregulated in NSCLC tissues and cell lines. High circPRKCA was correlated with TNM stage and lymph node metastasis of NSCLC patients. Silencing circPRKCA could suppress cell viability, migration, and invasion in A549 and H1299 cells, accompanied with apoptosis rate promotion. Moreover, circPRKCA knockdown retarded tumor growth of A549 cells in vivo. Molecularly, miR-330-5p was sponged by circPRKCA, and PDK1 was a target of miR-330-5p. Inhibiting miR-330-5p could attenuate the suppression of circPRKCA knockdown on cell growth, migration, and invasion; contrarily, promoting miR-330-5p caused inhibition on those cell behaviors by downregulating PDK1. Analogously, AKT activity was suppressed by circPRKCA downregulation and miR-330-5p upregulation in NSCLC cells both in vitro and in vivo.

Conclusion

Depleting circPRKCA inhibited PDK1 to suppress NSCLC cell malignant behaviors through miR-330-5p/PDK1/AKT pathway.

A novel small-molecule PI3K/Akt signaling inhibitor, W934, exhibits potent antitumor efficacy in A549 non-small-cell lung cancer

Small-molecule targeted antitumor drugs are considered to be a promising treatment that can improve the efficacy and reduce side effects. PI3K/Akt signaling pathway is constantly activated in various cancers. We recently synthesized a series of novel compounds of PI3K/Akt pathway inhibitors and found the most effective analog to be W934. In this study, we explored the in-vitro and in-vivo antitumor effects of W934 on A549 non-small-cell lung cancer cells and HCT116 colorectal cancer cells. In-vitro assays showed that W934 caused an inhibition of PI3Kα kinase. W934 can significantly suppress the viability of A549 and HCT116 cells with IC50 values of 0.25 and 0.23 μmol/l, respectively. Besides, the inhibitory effects on cell migration, invasion and apoptosis were also observed after treatment of W934 for the indicated hours. According to the cell cycle analysis, W934 caused an inhibition of G0-G1 phase progression and correspondingly decreased the percentage of cells in S and G2-M phases. Results of western blotting indicated that W934 concentration dependently suppressed the activation of the PI3K/Akt pathway. Meanwhile, the in-vivo effect was studied in an A549 xenograft mouse model. Oral administration of W934 inhibited the tumor growth in a dose-dependent manner. Hereby, W934 might be considered as a potential therapeutic drug candidate for non-small-cell lung cancer treatment.

Multimodal Imaging Mass Spectrometry to Identify Markers of Pulmonary Arterial Hypertension in Human Lung Tissue Using MALDI-ToF, ToF-SIMS, and Hybrid SIMS

Pulmonary arterial hypertension (PAH) is a rare and deadly disease affecting roughly 15-60 people per million in Europe with a poorly understood pathology. There are currently no diagnostic tools for early detection nor does a curative treatment exist. The lipid composition of arteries in lung tissue samples from human PAH and control patients were investigated using matrix-assisted laser desorption ionization (MALDI) imaging mass spectrometry (IMS) combined with time-of-flight secondary ion mass spectrometry (TOF-SIMS) imaging. Using random forests as an IMS data analysis technique, it was possible to identify the ion at m/z 885.6 as a marker of PAH in human lung tissue. The m/z 885.6 ion intensity was shown to be significantly higher around diseased arteries and was confirmed to be a diacylglycerophosphoinositol PI(C18:0/C20:4) via MS/MS using a novel hybrid SIMS instrument. The discovery of a potential biomarker opens up new research avenues which may finally lead to a better understanding of the PAH pathology and highlights the vital role IMS can play in modern biomedical research.

MICAL2 is a novel nucleocytoplasmic shuttling protein promoting cancer invasion and growth of lung adenocarcinoma

MICAL2 is a tumor-promoting factor involved in cell migration, invasion, deformation, and proliferation not yet fully explored in lung adenocarcinoma (LUAD). This study demonstrated that MICAL2 was overexpressed and cytoplasm-enriched in LUAD tissues. Moreover, high cytoplasmic MICAL2 and/or total MICAL2 expression levels were positively correlated with lymphatic metastasis and shorter overall survival in LUAD patients. MICAL2 promoted LUAD cell proliferation, migration, invasion, and epithelial to mesenchymal transition-all of which involved the AKT and myosin-9 pathways. Furthermore, MICAL2 was identified as a nucleoplasm shuttling protein dependent on myosin-9 and its C-terminal fragment. MICAL2-ΔC-enriched in the nucleus-had less impact on tumor malignancy in LUAD cells in vitro and in vivo. Tumor promotion by MICAL2 was reduced by nuclear-export inhibitor, myosin-9 inhibitor, or si-myosin-9-all of which effectively inhibited MICAL2's nuclear export. Finally, the expression and subcellular location as well as clinical significance of MICAL2 and myosin-9 were analyzed across TCGA data and LUAD tissue arrays. Our data revealed that MICAL2 overexpression and nuclear export were associated with cancer progression; inhibiting its expression and/or nuclear export may provide a new target for LUAD therapy.

Downregulation of hsa_circ_0007580 inhibits non-small cell lung cancer tumorigenesis by reducing miR-545-3p sponging

Non-small cell lung cancer (NSCLC) is a highly malignant tumor. Many circular RNAs (circRNAs) are reportedly in regulating the progression of NSCLC. To identify potential therapeutic targets for NSCLC, we conducted a bioinformatics analysis of circRNAs differentially expressed between NSCLC tissues and adjacent normal tissues. Hsa_circ_0007580 was upregulated in NSCLC tumor tissues, and the expression of its host gene (protein kinase Ca) correlated negatively with overall survival. Short-hairpin RNAs were used to knock down hsa_circ_0007580 in NSCLC cells, and gene and protein levels were measured with qRT-PCR and Western blotting, respectively. NSCLC cell proliferation, migration and apoptosis were evaluated with CCK-8 assays, Ki-67 staining, Transwell assays and flow cytometry, respectively. Knocking down hsa_circ_0007580 inhibited proliferation and invasion by NSCLC cells and induced their apoptosis. Dual luciferase reporter assays indicated that miR-545-3p can bind to hsa_circ_0007580 (suggesting that hsa_circ_0007580 sponges miR-545-3p) and to protein kinase Ca (suggesting that miR-545-3p directly inhibits this gene). In a xenograft tumor model, downregulating hsa_circ_0007580 inhibited NSCLC tumorigenesis by inactivating p38/mitogen-activated protein kinase signaling. Thus, silencing hsa_circ_0007580 notably inhibited NSCLC progression in vitro and in vivo, suggesting this circRNA could be a novel treatment target for NSCLC.

Deoxyshikonin inhibits cisplatin resistance of non-small-cell lung cancer cells by repressing Akt-mediated ABCB1 expression and function

Drug resistance is a large challenge for the treatment of non-small-cell lung cancer (NSCLC). Deoxyshikonin is the naphthoquinol compound with anticancer activity. However, the role and mechanism of deoxyshikonin in cisplatin resistance of NSCLC remain poorly understood. Cell viability was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide assay. Cell apoptosis was evaluated by flow cytometry and caspase-3 activity. We found that cisplatin-resistant A549/cis and H1299/cis cells had higher cisplatin resistance than A549 and H1299 cells, respectively. Deoxyshikonin contributed to cisplatin-induced viability inhibition and apoptosis in A549/cis and H1299/cis cells. Moreover, deoxyshikonin inhibited phosphorylation of Akt and the expression and function of ATP-binding cassette subfamily B member 1 (ABCB1). Activation of protein kinase B (Akt) pathway attenuated the effect of deoxyshikonin on cisplatin resistance and ABCB1 expression and function in A549/cis and H1299/cis cells. In conclusion, deoxyshikonin suppressed cisplatin resistance in cisplatin-resistant NSCLC cells by repressing Akt signaling-mediated ABCB1 expression.

[Effect of benzo(a)pyrene on the expression of AhR-regulated microRNA in female and male rat lungs]

Smoking is the main risk factor for lung cancer, mainly due to presence of nitrosamines and polycyclic aromatic hydrocarbons, including benzo[a]pyrene (BP) in tobacco smoke composition. The genotoxic effect of BP is based on the high DNA-binding ability of its metabolites, while the epigenetic effects are mediated by a change in the expression of cancer related genes or regulatory RNAs. It has been shown that women have a higher risk to develop lung cancer upon smoking rather than men. We hypothesized that crosstalk between signaling pathways activated by BP and estrogens could underlie the sex-dependent differences in miRNAs expression. To test this hypothesis, male and female rats were subjected to short-term or long-term BP exposure. Using in silico analysis, miRNAs containing the ER- and AhR-binding sites in the promoters of the genes (or host genes) were selected. During chronic exposure of BP the expression of miR-22-3p, -29a-3p, -126a-3p, -193b-5p in the lungs of male rats were significantly increased, while the level of miRNA-483-3p were decreased. Expression of miRNA-483-3p was up-regulated during chronic BP exposure in the lungs of female rats and the levels of other studied miRNAs were unchanged. In turn, changes in the expression of miRNAs were followed by changes in the expression of their target genes, including PTEN, EMP2, IGF1, ITGA6, SLC34A2, and the observed changes in female and male rat lungs were varied. Thus, our results suggest that sex-dependent epigenetic effects of BP may be based on different expression of AhR- and ER- regulated miRNAs.

miR-410 induces both epithelial-mesenchymal transition and radioresistance through activation of the PI3K/mTOR pathway in non-small cell lung cancer

Radiotherapy remains one of the major treatments for non-small cell lung cancer (NSCLC) patients; whereas intrinsic or acquired radioresistance limits its efficacy. Nevertheless, most studies so far have only focused on acquired resistance. The exact mechanisms of intrinsic radioresistance in NSCLC are still unclear. A few studies have suggested that epithelial–mesenchymal transition (EMT) is associated with radioresistance in NSCLC. However, little is known about whether the abnormal expression of specific microRNAs induces both EMT and radioresistance. We previously found that miR-410 has multiple roles as an oncomiRNA in NSCLC. In this study, we revealed that miR-410 overexpression promoted EMT and radioresistance, accompanied by enhanced DNA damage repair both in vitro and in vivo. Conversely, knockdown of miR-410 showed the opposite effects. We further demonstrated that PTEN was a direct target of miR-410 by using bioinformatic tools and dual-luciferase reporter assays, and the miR-410-induced EMT and radioresistance were reversed by PI3K, Akt, and mTOR inhibitors or by restoring the expression of PTEN in NSCLC cells. In addition, we preliminarily found that the expression of miR-410 was positively correlated with EMT and negatively associated with the expression of PTEN in NSCLC specimens. In summary, these results demonstrated that miR-410 is an important regulator on enhancing both NSCLC EMT and radioresistance by targeting the PTEN/PI3K/mTOR axis. The findings suggest that miR-410-induced EMT might significantly contribute to the enhanced radioresistance. Therefore, miR-410 may serve as a potential biomarker or therapeutic target for NSCLC radiotherapy.

Role of PI3K/AKT pathway in cancer: the framework of malignant behavior

Given that the PI3K/AKT pathway has manifested its compelling influence on multiple cellular process, we further review the roles of hyperactivation of PI3K/AKT pathway in various human cancers. We state the abnormalities of PI3K/AKT pathway in different cancers, which are closely related with tumorigenesis, proliferation, growth, apoptosis, invasion, metastasis, epithelial-mesenchymal transition, stem-like phenotype, immune microenvironment and drug resistance of cancer cells. In addition, we investigated the current clinical trials of inhibitors against PI3K/AKT pathway in cancers and found that the clinical efficacy of these inhibitors as monotherapy has so far been limited despite of the promising preclinical activity, which means combinations of targeted therapy may achieve better efficacies in cancers. In short, we hope to feature PI3K/AKT pathway in cancers to the clinic and bring the new promising to patients for targeted therapies.

The interaction of interleukin-8 and PTEN inactivation promotes the malignant progression of head and neck squamous cell carcinoma via the STAT3 pathway

Interleukin-8 (IL-8) expression correlates with poor prognosis in many cancers, including head and neck squamous cell carcinoma (HNSCC), but the underlying mechanism is poorly understood. In this study, we found that overexpression of IL-8 correlated with poor outcome in HNSCC patients. IL-8 significantly increased cellular proliferation, migration, and invasion ability both in vitro and in vivo, which could be blocked by a CXCR1/2 inhibitor. IL-8 promoted the expression of MMP2, MMP9, snail, and vimentin in HNSCC cells. Furthermore, IL-8 could inactivate PTEN via phosphorylation, and then inactivated PTEN affected the phosphorylation of STAT3. Recombinant PTEN that internalized in cytoplasm decreased the expression of phosphorylated STAT3, while knockdown of PTEN led to the increased expression of phosphorylated STAT3. A STAT3 inhibitor could reverse the upregulation of invasion-associated proteins mediated by IL-8 stimulation. Furthermore, overexpression of snail and inactivated PTEN jointly promoted the autocrine effect of IL-8 on tumor cells. Last, there were positive correlations between IL-8 and snail, vimentin expression in HNSCC tissues. In summary, our study demonstrates that PTEN acts as a novel "molecular switch" to regulate IL-8/STAT3 signaling, promoting the progression of HNSCC, and indicating that this pathway may be a potential therapeutic target for HNSCC.

Long non-coding RNA DDX11-AS1 promotes non-small cell lung cancer development via regulating PI3K/AKT signalling

Non-small cell lung cancer (NSCLC) has been considered to be the most common category of lung cancer, comprising approximately 80% of lung cancers. Long non-coding RNAs (lncRNAs) were diffusely documented to modulate carcinogenesis or progression of tumours. However, the role of DDX11-AS1 was still unclear in NSCLC. Bioinformatics analysis and experimental assays including hematoxylin and eosin (H&E) staining, RT-qPCR, colony formation, CCK-8, flow cytometry, western blot and xenograft assays were applied to investigate the biological role and molecular mechanism of DDX11-AS1 in NSCLC. The level of lncRNA DDX11-AS1 was up-regulated in NSCLC tumour tissues and cells. In function aspect, knockdown of DDX11-AS1 caused an apparent inhibitive effect on cell proliferation in vitro and in vivo. DDX11-AS1 inhibition promoted cell apoptosis in vitro. In mechanism, the protein level of phosphorylated AKT was reduced by DDX11-AS1 inhibition but increased by DDX11-AS1 overexpression. These results indicated that DDX11-AS1 exacerbated NSCLC progression via activating PI3K/AKT signalling pathway. All in all, DDX11-AS1 promotes NSCLC development via regulating PI3K/AKT signalling.

CircRNA: a rising star in gastric cancer

In recent years, a large number of circRNAs have been identified in mammalian cells with high-throughput sequencing technologies and bioinformatics. The aberrant expression of circRNAs has been reported in many human diseases including gastric cancer (GC). The number of GC-related circRNAs with validated biological functions and mechanisms of action is growing. CircRNAs are critically involved in GC cell proliferation, apoptosis, migration, and invasion. CircRNAs have been shown to function as regulators of parental gene transcription and alternative splicing and miRNA sponges. Moreover, circRNAs have been suggested to interact with proteins to regulate their expression level and activities. Several circRNAs have been identified to encode functional proteins. Due to their great abundance, high stability, tissue- and developmental-stage-specific expression patterns, and wide distribution in various body fluids and exosomes, circRNAs exhibit a great potential to be utilized as biomarkers for GC. Herein, we briefly summarize their biogenesis, properties and biological functions and discuss about the current research progress of circRNAs in GC with a focus on the potential application for GC diagnosis and therapy.

Lamin B1 Overexpresses in Lung Adenocarcinoma and Promotes Proliferation in Lung Cancer Cells via AKT Pathway

PURPOSE

This study aims to investigate the biological effect and molecular mechanism of Lamin B1(LMNB1) in lung cancer cells and its significance for the prognosis of lung adenocarcinoma(LUAD) patients.

METHODS

In this study, Bioinformatics was performed to analyze the expression at mRNA level and prognosis effect of LMNB1 in LUAD from TCGA dataset. The immunohistochemistry(IHC) assay was conducted to analyzed the expression of LMNB1 at the protein level in LUAD tissues. The correlation between the expression of LMNB1 and the clinical factors in patients with LUAD was analyzed. Next, LMNB1 transfected into LUAD cell lines (A549 and PC-9) which was proved by Western blot. CCK8 assay, cloning formation assay, and xenograft assay were conducted to explore the effect and mechanism of LMNB1 on the proliferation of LUAD cell lines in vitro and in vivo.

RESULTS

The results of the present study demonstrated that LMNB1 was highly expressed in LUAD tissues and related to tumor stage. High LMNB1 expression was related with more advanced clinicopathological factors such as low degree of differentiation (P=0.02), large tumor size (P<0.01), lymph node metastasis (P<0.01) and higher tumor stage (P<0.01). After knocking down LMNB1, the cell growth rate (P<0.01) and the number of colonies (P<0.01) were significantly reduced, and the level of the proliferating marker Ki67 (P<0.01) was significantly decreased. At the same time, in vivo experiments showed that the tumor volume and tumor of the mice were significantly reduced (P<0.01). Moreover, we found that knockdown LMNB1 can inhibit the proliferation of lung cancer cells by inhibiting AKT phosphorylation by Western blot.

CONCLUSION

In summary, LMNB1 play an of vital roles in the growth of LUAD cells, highlighting its potential as a therapeutic target for the treatment of LUAD patients.

An Inventive Report of Inducing Apoptosis in Non-Small Cell Lung Cancer (NSCLC) Cell Lines by Transfection of MiR-4301

BACKGROUND

Based on recent studies, new therapeutic strategies have been developed for cancer treatment using microRNAs (miRNAs). With this view, miRNAs manipulating techniques can be considered as novel therapeutic prospects for cancer treatment. In this study, we evaluated the expression of miR-4301 in human lung cancer cell lines and investigated its potential role in cell proliferation and tumor suppression on Non-Small Cell Lung Cancer (NSCLC) cells.

METHODS

We used quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) to examine the level of miR- 4301 expression in human lung cancer cell lines (A549, QU-DB) and non-malignant lung epithelial cells (HFLF-PI5). Then, we investigated the effect of miR-4301 by transfecting it into these cell lines and probing for cancer cell viability and apoptosis using the MTT assay, flow cytometry and immunofluorescence staining.

RESULTS

Our results showed that the expression level of miR-4301 was significantly reduced in human lung cancer cell lines (P<0.001). When miR-4301 was transfected in lung cancer cells, their cell proliferation was suppressed and apoptosis induced. This decline in cell survival was confirmed by the MTT assay. Transfection of miR-4301 caused an increase in early and late apoptotic cells in all lung cancer cell lines tested.

CONCLUSIONS

Our findings show that miR-4301 may act as a lung cancer suppressor through targeting of proteins involved in cell proliferation and survival. For this reason, targeting miR-4301 may provide a new strategy for the diagnosis and treatment of patients with this deadly disease. This article is protected by copyright. All rights reserved.