Lung Cancer Cell Cycle Research Articles

Prognostic and immunological potential of PPM1G in lung adenocarcinoma.

Lung cancer is one of the most common types of cancer worldwide, with the highest incidence and mortality rates. Protein phosphatase, Mg2+/Mn2+ dependent 1G (PPM1G) is a serine/threonine phosphatase, which is involved in the proliferation, invasion and metastasis of tumor cells. However, there are few reports on the role of PPM1G in lung adenocarcinoma (LUAD). The present study used publicly available data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus databases to evaluate the expression of PPM1G in LUAD, and to assess the relationship between PPM1G expression and the prognosis of patients with LUAD. Protein expression data of PPM1G obtained by immunohistochemical staining were collected from the Human Protein Atlas database. The correlation between PPM1G and immune cell infiltration and immune checkpoints was analyzed by single‑sample gene set enrichment analysis of TCGA data. The Kaplan‑Meier method was used for survival analysis, and univariate and multivariate Cox regression were used to analyze the effect of PPM1G on prognosis with data from TCGA database. The results showed that PPM1G was highly expressed in LUAD cancer tissues. The high expression of PPM1G was associated with poor clinical stage, T stage, N stage and overall survival in LUAD. The present study screened 29 genes related to PPM1G and closely related to the cell cycle in patients with LUAD. The expression of PPM1G was positively correlated with γδ‑Τ cells, T helper 2 cells and natural killer CD56dim cells, and was negatively correlated with B cells, mast cells, plasmacytoid dendritic cells, T helper cells, macrophages, T cells, CD8 T cells, central memory T cells, effector memory T cells, neutrophils and T follicular helper cells. In addition, PPM1G was positively correlated with immune detection points. In conclusion, PPM1G may be involved in the control of the lung cancer cell cycle, and could be associated with prognosis and immune infiltration in patients with LUAD.

Engineered Bacteriorhodopsin May Induce Lung Cancer Cell Cycle Arrest and Suppress Their Proliferation and Migration.

Highly expressible bacteriorhodopsin (HEBR) is a light-triggered protein (optogenetic protein) that has seven transmembrane regions with retinal bound as their chromophore to sense light. HEBR has controllable photochemical properties and regulates activity on proton pumping. In this study, we generated HEBR protein and incubated with lung cancer cell lines (A549 and H1299) to evaluate if there was a growth-inhibitory effect with or without light illumination. The data revealed that the HEBR protein suppressed cell proliferation and induced the G0/G1 cell cycle arrest without light illumination. Moreover, the migration abilities of A549 and H1299 cells were reduced by ~17% and ~31% after incubation with HEBR (40 μg/mL) for 4 h. The Snail-1 gene expression level of the A549 cells was significantly downregulated by ~50% after the treatment of HEBR. In addition, HEBR significantly inhibited the gene expression of Sox-2 and Oct-4 in H1299 cells. These results suggested that the HEBR protein may inhibit cell proliferation and cell cycle progression of lung cancer cells, reduce their migration activity, and suppress some stemness-related genes. These findings also suggested the potential of HEBR protein to regulate the growth and migration of tumor cells, which may offer the possibility for an anticancer drug.

Study the antioxidant effects of blue-green algae Spirulina extract on ROS and MDA production in human lung cancer cells

In order to study the effects of Spirulina, Arthrospira platensis, two cell lines of A549 and HFF were treated with the concentration of IC50 for 24 h. MTT analysis showed that the highest decrease in viability of cells happened at the concentration of 500 μg/ml. The necrosis, releases of LDH, produced DCFH, and Lipid peroxidation were higher in the cancer cell lines in comparison to normal cells. Results showed that the extract affected the cell cycle of the A549 cell line. Also, the algal extract had concentration-dependent antioxidant activity. Also, the production of malonyl dialdehyde was significantly higher in treated cells and there was a significant relationship between produced MDA and ROS. Results showed that A. platensis extract had a remarkable effect on the lung cancer cell cycle and arrest the cell cycle in phase G2; so the cells didn't enter phase M and the proliferation of cancer cells prevented. Furthermore, according to the higher production of ROS and MDA in treated A549 cancer cell lines, it could be concluded that this algal extract could be considered as a natural product with anticancer activity against lung cancer cells.

Effects of water-soluble components of atmospheric particulates from rare earth mining areas in China on lung cancer cell cycle

BackgroundThis study aims to investigate the effects of water soluble particulate matter (WSPM) on the viability and protein expression profile of human lung adenocarcinoma cell A549 in the Bayou Obo rare earth mining area, and explore the influence of WSPM on the A549 cell cycle.ResultsIt was found that WSPM can inhibit the viability of A549 cells and induce cell arrest in the G2/M phase. Compared with controls, exposure to WSPM10 and WSPM2.5 induced 134 and 116 proteins to be differentially expressed in A549 cells, respectively. In addition, 33 and 31 differentially expressed proteins were further confirmed, and was consistent with the proteomic analysis. The most prominent enrichment in ribosome-associated proteins were presented. When RPL6, RPL13, or RPL18A gene expression was inhibited, A549 cells were arrested in the G1 phase, affecting the expression of Cyclin D1, p21, RB1, Cyclin A2, Cyclin B1, CDC25A, CDK2, CHEK2 and E2F1. Furthermore, the La3+, Ce3+, Nd3+ and F- in WSPM also inhibited the viability of A549 cells. After 24 h of exposure to 2 mM of NaF, A549 cells were also arrested in the G2/M phase, while the other three compounds did not have this effect. These four compounds affected the cell cycle regulatory factors in A549 cells, mainly focusing on effecting the expression of CDK2, CDK4, RB1, ATM, TP53 and MDM2 genes. These results are consistent with the those from WSPM exposure.ConclusionsThese results revealed that WSPM from rare earth mines decreased the viability of A549 cells, and induced cell cycle G2/M phase arrest, and even apoptosis, which may be independent of the NF-κB/MYD88 pathway, and be perceived by the TLR4 receptor. The dysfunction of the cell cycle is correlated to the down-expression of ribosomal proteins (RPs). However, it is not the direct reason for the A549 cell arrest in the G2/M phase. La3+, Ce3+, and F- are probably the main toxic substances in WSPM, and may be regulate the A549 cell cycle by affecting the expression of genes, such as MDM2, RB1, ATM, TP53, E2F1, CDK2 and CDK4. These results indicate the importance for further research into the relationship between APM and lung cancer.

LncRNA HOXB-AS3 exacerbates proliferation, migration, and invasion of lung cancer via activating the PI3K-AKT pathway.

Lung cancer remains the leading cause of cancer-related death all over the world. In spite of the great advances made in surgery and chemotherapy, the prognosis of lung cancer patients is poor. A substantial fraction of long noncoding RNAs (lncRNAs) can regulate various cancers. A recent study has reported that lncRNA HOXB-AS3 plays a critical role in cancers. However, its biological function remains unclear in lung cancer progression. In the current research, we found HOXB-AS3 was obviously elevated in NSCLC tissues and cells. Functional assays showed that inhibition of HOXB-AS3 was able to repress A549 and H1975 cell proliferation, cell colony formation ability and meanwhile, triggered cell apoptosis. Furthermore, the lung cancer cell cycle was mostly blocked in the G1 phase whereas the cell ratio in the S phase was reduced. Also, A549 and H1975 cell migration and invasion capacity were significantly repressed by the loss of HOXB-AS3. The PI3K/AKT pathway has been implicated in the carcinogenesis of multiple cancers. Here, we displayed that inhibition of HOXB-AS3 suppressed lung cancer cell progression via inactivating the PI3K/AKT pathway. Subsequently, in vivo experiments were utilized in our study and it was demonstrated that HOXB-AS3 contributed to lung cancer tumor growth via modulating the PI3K/AKT pathway. Overall, we implied that HOXB-AS3 might provide a new perspective for lung cancer treatment via targeting PI3K/AKT.

Abstract 4429: Delivery of miR-143 and miR-506 with novel nano carrier to arrest cell cycle in lung cancer

Abstract Lung cancer is the leading cause of cancer related deaths worldwide. Although targeting the cell cycle of cancer cells has been a promising approach, no such therapy has translated for the treatment of lung cancer. In our previous work, we identified that the combinatorial treatment of two miRNAs, miR-143 and miR-506, inhibited the cell cycle of lung cancer cells in vitro. These miRs downregulated the CDK1 and CDK4/6 genes, which are involved in the G1/S and G2/M transitions, respectively. Nucleic acid delivery has met formidable challenges, such as short in vivo half-life and rapid degradation in the circulation, as well as limited cell penetration or endosomal escape. We developed a novel nanocarrier, composed of tocopherol (vitamin E), polyethylenenimine, and polyethylene glycol (TPP) in 1:1:1 molar ratio for the delivery of miRNAs. Proper characterization with NMR and FTIR confirmed the synthesis of this molecule. We found it can form nanomicelles, and the positively charged of polyethyleneimine allowed for the complexation of miRNAs, as was detected by a gel retardation assay. Fluorescently tagged TPP micelles were uptaken by cancer cells, and the carrier successfully transfected cancer cells with the combinatorial miRNA treatment inducing gene downregulation. In vivo pharmacokinetics study using a subcutaneous mouse model of lung cancer indicated prolonged accumulation of the TPP-miRNA micelles in the tumor area. In vivo administration of the miR-143/506 in TPP micelles, along with cisplatin co-treatment, inhibited tumor growth in a subcutaneous mouse model of lung cancer. Overall, the promising role of miR-143 and 506 for the regulation of LC growth may be achieved by this novel TPP-based nanocarrier, which merits further evaluation. Citation Format: A K M Nawshad Hossian, Chandra Mohan Reddy Muthumula, George Mattheolabakis. Delivery of miR-143 and miR-506 with novel nano carrier to arrest cell cycle in lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4429.

P069 HOTAIR, A Long Non-Coding RNA, Is a Marker of Abnormal Cell Cycle Regulation in Lung Cancer

The dis-regulation of cell cycle is an obvious marker of tumors including lung cancer. Recently, the study of cell cycle inhibitor has made great progress in lung cancer. While a question, what kinds of patients could use cell cycle inhibitor, has plagued us. So seeking an accurate and convenient marker for the abnormal cell cycle in lung cancer is very important. MTT, EdU, Transwell, ChIRP, Western-blot, luciferase reporter assay, Orthotopic nude mouse model, Immunohistochemistry. In the present research we had showed lnc-RNA HOTAIR is an optimal indicator of cell cycle dis-regulation in lung cancer. HOTAIR specific expression in lung primary tumor sample by the analysis of TCGA public database and 67 pairs of patients’ tissues from our department. And through the TCGA public database KEGG analysis, HOTAIR is correlated with cell cycle pathway. Then we identified that HOTAIR and its 2 segments, HOTAIR3’ and HOTAIR5’, promote the cell cycle passing through the restriction point during G1-S phase by regulating Rb-E2Fs pathway and influence NSCLC cell proliferation, migration, and invasion through epithelial-mesenchymal transition (EMT) and β-catenin pathway in vitro and vivo. Last we had also showed the high expression of HOTAIR associated with fast resistance to gefitinb through dis-regulated cell cycle. In conclusion, HOTAIR could be an ideal indicator of cell cycle dysregulation and guide the use of cell cycle inhibitor.

HOTAIR, a long noncoding RNA, is a marker of abnormal cell cycle regulation in lung cancer.

Dysregulation of the cell cycle is a key indicator of tumors, including lung cancer. Recently, the study of cell cycle inhibitors has made great progress in relation to lung cancer. However, the question of what kinds of patients can use cell cycle inhibitors has plagued us. Therefore, seeking an accurate and convenient marker for the abnormal cell cycle in lung cancer is very important. In the present research, we showed that lncRNA HOTAIR is an optimal indicator of cell cycle dysregulation in lung cancer. In the present study, we investigated HOTAIR‐specific expression in lung primary tumor samples by analyzing the TCGA public database and 67 pairs of patients’ tissues collected from our department. Through the TCGA public database KEGG analysis, HOTAIR correlates with the cell cycle pathway. We identified that HOTAIR and its 2 segments, HOTAIR3′ and HOTAIR5′, promote the cell cycle passing through the restriction point during G1‐S phase by regulating the Rb‐E2F pathway and influence non–small‐cell lung cancer cell proliferation, migration and invasion through epithelial‐mesenchymal transition (EMT) and the β‐catenin pathway in vitro and vivo. Finally, we showed that the high expression of HOTAIR was associated with resistance to gefitinib through the dysregulated cell cycle. In conclusion, HOTAIR could be an ideal indicator of cell cycle dysregulation and guide the use of cell cycle inhibitors.

Overexpression of KIF20A confers malignant phenotype of lung adenocarcinoma by promoting cell proliferation and inhibiting apoptosis

Increasing studies showed that kinesin family member 20A (KIF20A) was overexpessed in several types of cancer, and its overexpression correlated with the oncogenesis and prognosis of cancers. However, little is known about the role of KIF20A in lung adenocarcinoma (LUAD). In this study, we employed the bioinformatics analysis to identify the upregulation of KIF20A in LUAD, then verified the results in human tumor specimens and LUAD cell lines. Compared with normal lung tissues, a ubiquitous upregulation of KIF20A was observed in LUAD tissues by immunohistochemistry (IHC) as well as TCGA analysis. Higher expression of KIF20A was significantly associated with more advanced clinicopathological features and shorter overall survival (OS). Moreover, multivariate Cox regression analysis revealed that KIF20A was an independent prognostic factor for OS. The expression of KIF20A was significantly elevated in LUAD cell lines. After silencing KIF20A, lung cancer cell cycle arrested in G1 phase and apoptosis increased. The same results were observed in vivo. Thus, our study demonstrated that KIF20A might confer malignant phenotype to LUAD by regulating cell proliferation and apoptosis, providing a new potential biomarker for clinical treatment of LUAD.

Multipronged activity of combinatorial miR-143 and miR-506 inhibits Lung Cancer cell cycle progression and angiogenesis in vitro

Lung cancer (LC) is the leading cause of cancer-related deaths. Downregulation of CDK1, 4 and 6, key regulators of cell cycle progression, correlates with decreased LC cell proliferation. Enforced expression of miRNAs (miRs) is a promising approach to regulate genes. Here, we study the combinatorial treatment of miR-143 and miR-506 to target the CDK1, 4/6 genes, respectively. We analyzed the differential expression of CDK genes by qPCR, and western blot, and evaluated changes in the cell cycle distribution upon combinatorial treatment. We used an antibody microarray analysis to evaluate protein expression, focusing on the cell cycle pathway, and performed RNA-sequencing for pathway analysis. The combinatorial miR treatment significantly downregulated CDK1, 4 and 6 expression, and induced a shift of the cell cycle populations, indicating a G1 and G2 cell cycle block. The two miRs induces strong cytotoxic activity, with potential synergism, and a significant Caspase 3/7 activation. We identified a strong inhibition of tube formation in the presence or absence VEGF in an in vitro angiogenesis model. Together with the pathways analysis of the RNA-sequencing data, our findings establish the combinatorial miR transfection as a viable strategy for lung cancer treatment that merits further investigation.

MiR-21 induces cell cycle at S phase and modulates cell proliferation by down-regulating hMSH2 in lung cancer

MicroRNAs regulate critical genes associated with lung cancer. Human mutS homolog 2 (hMSH2), one of the core mismatch repair genes, is affected in lung cancer development. The aim of this study is to investigate the role of miR-21 in hMSH2 gene expression and the effect of miR-21 on cell proliferation and cell cycle in lung cancer. The targets of miR-21 were predicted by a bioinformatics tool, and hMSH2 was validated as a direct target of miR-21 by luciferase activity assay. MiRNA mimics or inhibitors were used to stimulate or attenuate the effect of endogenous miR-21 on hMSH2 expression. MiR-21 and hMSH2 expressions were assessed with real-time RT-PCR and Western blotting. Cell cycle was determined by flow cytometry, and cell growth was analyzed by MTT assay and real-time cell analysis system. MiR-21 expression was inversely correlated with hMSH2 expression in human lung cancer cell lines. Further validation showed hMSH2 was directly regulated by miR-21. The up-regulation of miR-21 significantly promoted cell proliferation and revealed a higher proportion of cells at S phase. However, knockdown of miR-21 expression resulted in cell cycle arrest at G2/M phase and inhibited cell proliferation. These data suggest miR-21 is a key regulator of hMSH2 and modulates cell cycle and proliferation by targeting hMSH2 in human lung cancer.

Molecular imaging of p53 signal pathway in lung cancer cell cycle arrest induced by cisplatin

Cisplatin is a commonly employed chemotherapy drug for lung malignancy. However its efficacy is limited by acquired drug resistance and lacking of an in vivo real-time monitoring approach. The aim of this study is to investigate the effect of cisplatin on lung adenocarcinoma cell line p53-RE-Fluc/A549 in vivo via non-invasive reporter gene by molecular imaging. For this study, we employed p53-RE-Fluc/A549 cells that overexpressed a vector with three tandem repeats of p53 response element followed by the luciferase reporter gene. P53 activity was evaluated by optical imaging and verified by Western blot after cells were exposed to 10 µM cisplatin for 72 h. The cell cycle was mainly blocked at the S- and G2/M-phases after cisplatin treatment, whereas no significant change was observed in cell apoptotic index. Increased expression of p21 and Bcl-2 as well as decreased expression of Bax were observed after cisplatin treatment by Western blotting. Longitudinal in vivo bioluminescent imaging (BLI) revealed that the p53 activity was increased from 24 to 48 h after transient cisplatin treatment in p53-RE-Fluc/A549-bearing nude mice. RNA sequencing further revealed that cell cycle and p53 signaling pathway genes, such as E2F1, CCNA2, CDK1, and CCNE2 were significantly downregulated after long-term cisplatin treatment. Thus, our study showed that cisplatin exerts its cytotoxic effect through blockage of the cell cycle and may be partly regulated by the p53 signaling pathway. Furthermore, molecular imaging is a useful tool to investigate the mechanism and evaluate the effect of chemotherapy drugs both in vivo and in vitro.

Synthesis of 6-substituted 9-methoxy-11H-indeno[1,2-c]quinoline-11-one derivatives as potential anticancer agents

We have synthesized certain 6-substituted 9-methoxy-11H-indeno[1,2-c]quinolin-11-ones for antiproliferative evaluation. Results indicated that 6-alkylamine derivatives, 6-[2-(dimethylamino)ethylamino]-9-methoxy-11H-indeno[1,2-c]quinolin-11-one (5a) and its 6-[3-(dimethylamino)propylamino] derivative, 5b, were able to inhibit cells growth completely at a concentration of 100μM while most of the 6-arylamine derivatives 6b–6h were inactive at the same concentration. Comparable mean GI50 (drug molar concentration causing 50% cell growth inhibition) values for 5a (3.47μM) and 5b (3.39μM) indicated the cytotoxicity may not be affected by the length of alkyl substituents at C-6 position. Compound 5b, with a mean GI50 value of 3.39μM, was the most active and therefore was selected for further evaluation on its effects of H460 lung cancer cell cycle distribution. Results indicated that 5b induced cell cycle arrest in G2/M phase after 24h treatment, while the hypodiploid (sub-G0/G1 phase) cells increased. We found that H460 cell became shrinked after the treatment of 5b, indicating that apoptosis may be a mechanism by which 5b kills the cancer cells. DNA unwinding assay indicated that 5b may bind to DNA through intercalation. Our results have also demonstrated that PARP was cleaved while caspase-3 and caspase-8 activities were induced after the treatment of 5b at 10μM for 24h. Thus, compound 5b intercalates DNA, induces cell cycle arrest at G2/M phase via cleavage of PARP, induces caspase-3 and caspase-8 activities, and consequently causes the cell death.

Differential Effects of selenium on the proliferation of human pulmonary adenocarcinoma cells and human embryonic lung diploid cells in vitro

The effect of different concentrations of Na2SeO3 on human pulmonary adenocarcinoma cells and human embryonic lung diploid cells in vitro was investigated. For human pulmonary adenocarcinoma cells, mitotic index and cell count decreased with increasing selenium concentrations. At 1 μg/mL sodium selenite, mitotic activity and growth of human lung cancer cells were partially inhibited, and the progression of human lung cancer cell cycle was partially arrested. When human embryonic lung diploid cells were treated with 1 μg/mL sodium selenite for five continuous days, cell counts of the treated group were closely parallel to those of the control group. After treating human embryonic lung diploid cells with 1-5μg/mL sodium selenite for 1-3 d, the mitotic index (MI), labeled index (LI), and average silver grain (SG) number per 20 labeled nuclei were the same as those of the control. In mixed cultures of human embryonic lung diploid cells and human pulmonary adenocarcinoma cells, treated with 3 and 5 μg/mL sodium selenite for 24 h, the lung diploid cells showed a normal fusiform morphology, whereas the lung cancer cells showed heavily vacuolated cytoplasms and distorted nuclei.