Suppressed Non-small Cell Lung Cancer Progression Research Articles

CircPTP4A2 knockdown suppresses NSCLC progression via regulating proliferation and activating anti-tumor immunity

BackgroundWith a considerable variety of cancer subtypes, Non-small cell lung cancer (NSCLC) poses a substantial threat to public health, affecting a large number of individuals and resulting in a high mortality rate. Circular RNA (circRNA) has been applied in various diseases, including cancers. This study aims to investigate the clinial significance and functional role of circPTP4A2 in NSCLC.MethodsThe serum and tissue samples were collected for detecting circPTP4A2 expression in NSCLC using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Actinomycin D was used to treat NSCLC cells to detect circPTP4A2 stability. The CCK-8 and Transwell assays were utilized to assess the effects of circPTP4A2 in NSCLC cells. The ELISA assay and cytotoxicity analysis were used to detect the roles of circPTP4A2 in immune escape.ResultsThe serum and tissue circPTP4A2 expression was upregulated in NSCLC. The high circPTP4A2 had a relatively high value in differentiating NSCLC patients from healthy individuals. The proliferation, invasion, and immune escape were repressed by circPTP4A2 knockdown.ConclusionsHigh circPTP4A2 has the potential to be a diagnostic biomarker in NSCLC. Silencing of circPTP4A2 receded the progression of NSCLC and enhanced antitumor immunity, which might provide potential targets and new ideas for improving the diagnosis and effect of immunotherapy in NSCLC patients.

NAT10-mediated upregulation of GAS5 facilitates immune cell infiltration in non-small cell lung cancer via the MYBBP1A-p53/IRF1/type I interferon signaling axis

Interactions of tumor cells with immune cells in the tumor microenvironment play an important role during malignancy progression. We previously identified that GAS5 inhibited tumor development by suppressing proliferation of tumor cells in non-small cell lung cancer (NSCLC). Herein, we discovered a tumor-suppressing role for tumor cell-derived GAS5 in regulating tumor microenvironment. GAS5 positively coordinated with the infiltration of macrophages and T cells in NSCLC clinically, and overexpression of GAS5 promoted macrophages and T cells recruitment both in vitro and in vivo. Mechanistically, GAS5 stabilized p53 by directly binding to MYBBP1A and facilitating MYBBP1A-p53 interaction, and enhanced p53-mediated transcription of IRF1, which activated type I interferon signaling and increased the production of downstream CXCL10 and CCL5. We also found that activation of type I interferon signaling was associated with better immunotherapy efficacy in NSCLC. Furthermore, the stability of GAS5 was regulated by NAT10, the key enzyme responsible for N4-acetylcytidine (ac4C) modification, which bound to GAS5 and mediated its ac4C modification. Collectively, tumor cell-derived GAS5 could activate type I interferon signaling via the MYBBP1A-p53/IRF1 axis, promoting immune cell infiltration and potentially correlating with immunotherapy efficacy, which suppressed NSCLC progression. Our results suggested GAS5 as a promising predictive marker and potential therapeutic target for combination therapy in NSCLC.A schematic diagram demonstrating the regulatory effect of GAS5 on immune cell infiltration by activating type I interferon signaling via MYBBP1A-p53/IRF1 axis in non-small cell lung cancer. IFN, interferon.

ITGA9-AS1 up-regulates ITGA9 by targeting miR-4765 and recruiting HNRNPU to affect the proliferation and apoptosis of non-small cell lung cancer cells.

Long non-coding RNAs (lncRNAs) have been regarded as promising biomarkers in the regulation of various biological and pathological processes of non-small cell lung cancer (NSCLC). LncRNAITGA9-AS1 has been reported to be down-regulated in elderly patients with lung cancer, but how it may influence NSCLC remains to be identified. Therefore, we aim to explore the specific mechanism involving ITGA9-AS1 and ITGA9 in NSCLC. A functional assay was conducted to verify ITGA9-AS1's proliferative effects on NSCLC cells. Mechanism experiments with bioinformatics predictions were performed to explore the interaction of ITGA9-AS1 and ITGA9 in NSCLC cells. ITGA9-AS1 inhibited NSCLC cell proliferation while enhancing cell apoptosis. It up-regulated ITGA9 by competitively sponging miR-4765, and it stabilizedITGA9 mRNA by recruiting a RNA-binding protein (RBP)-HNRNPU (heterogeneous nuclear ribonucleoprotein U) in NSCLC cells. ITGA9-AS1 suppressed NSCLC progression by the up-regulation of ITGA9 via targeting miR-4765 and recruiting HNRNPU.

An antioxidant feedforward cycle coordinated by linker histone variant H1.2 and NRF2 that drives nonsmall cell lung cancer progression

Nonsmall cell lung cancer (NSCLC) is highly malignant with limited treatment options, platinum-based chemotherapy is a standard treatment for NSCLC with resistance commonly seen. NSCLC cells exploit enhanced antioxidant defense system to counteract excessive reactive oxygen species (ROS), which contributes largely to tumor progression and resistance to chemotherapy, yet the mechanisms are not fully understood. Recent studies have suggested the involvement of histones in tumor progression and cellular antioxidant response; however, whether a major histone variant H1.2 (H1C) plays roles in the development of NSCLC remains unclear. Herein, we demonstrated that H1.2 was increasingly expressed in NSCLC tumors, and its expression was correlated with worse survival. When crossing the H1c knockout allele with a mouse NSCLC model (KrasLSL-G12D/+), H1.2 deletion suppressed NSCLC progression and enhanced oxidative stress and significantly decreased the levels of key antioxidant glutathione (GSH) and GCLC, the catalytic subunit of rate-limiting enzyme for GSH synthesis. Moreover, high H1.2 was correlated with the IC50 of multiple chemotherapeutic drugs and with worse prognosis in NSCLC patients receiving chemotherapy; H1.2-deficient NSCLC cells presented reduced survival and increased ROS levels upon cisplatin treatment, while ROS scavenger eliminated the survival inhibition. Mechanistically, H1.2 interacted with NRF2, a master regulator of antioxidative response; H1.2 enhanced the nuclear level and stability of NRF2 and, thus, promoted NRF2 binding to GCLC promoter and the consequent transcription; while NRF2 also transcriptionally up-regulated H1.2. Collectively, these results uncovered a tumor-driving role of H1.2 in NSCLC and indicate an "H1.2-NRF2" antioxidant feedforward cycle that promotes tumor progression and chemoresistance.

Silencing of long non-coding RNA linc01106 suppresses non-small cell lung cancer proliferation, migration and invasion by regulating microRNA-765

Long non-coding RNAs (lncRNAs) are actively involved in various carcinomas. The purpose of this experiment is to explore the function of long intergenic non-protein coding RNA 01106 (LINC01106) in non-small cell lung cancer (NSCLC). LINC01106 expression in NSCLC was determined by RT-qPCR. Next, the distribution of LINC01106 in A549 cells was observed using subcellular fractionation. Subsequently, functional assays were performed to access NSCLC cell biological behaviors, with epithelial–mesenchymal transition detected by the western blot analysis. After that xenograft tumors were established in nude mice to analyze the inhibitory role of LINC01106 knockdown in NSCLC. In addition, gain-of-function and loss-of-function assays were carried out to confirm the interaction between LINC01106 and microRNA (miR)-765 and between miR-765 and collagen type III (COL3A1) in NSCLC cells. LINC01106 was overexpressed in NSCLC cells, and it existed in both cytoplasm and nuclei in A549 cells. Then, it was further discovered that LINC01106 knockdown greatly reduced NSCLC cell expansion and tumor growth in vivo. Furthermore, it was identified that LINC01106 could serve as a sponge of miR-765 to promote COL3A1 expression. miR-765 overexpression inhibited A549 cell activities. This study unmasked that LINC01106 knockdown suppressed NSCLC progression by serving as a sponge of miR-765 to downregulate COL3A1 expression.

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.

CircPUM1 promotes cell growth and glycolysis in NSCLC via up-regulating METTL3 expression through miR-590-5p

ABSTRACT RNA pumilio RNA binding family member 1 (circPUM1) has been reported to play important roles in the tumorigenesis of several cancers. However, the underlying molecular role of circPUM1 in non-small cell lung cancer (NSCLC) progression remains unknown. The qRT-PCR and western blot were used to evaluate the expression of RNAs and proteins. In vitro cell proliferation assays, flow cytometric and glucose metabolism analyses were performed to test the effects of circPUM1 and its target on NSCLC cell growth and glycolysis. The interaction between microRNA (miR)-590-5p and circPUM1 or methyltransferase like 3 (METTL3) was analyzed by using dual-luciferase reporter, pull-down or RNA immunoprecipitation (RIP) assays. Murine xenograft model was established to conduct in vivo experiments. CircPUM1 was highly expressed in NSCLC tissues and cell lines. CircPUM1 knockdown suppressed cell proliferation, cell cycle and glycolysis in vitro. Moreover, circPUM1 directly bound to miR-590-5p, and miR-590-5p inhibitor reversed the inhibitory effects of circPUM1 knockdown on NSCLC carcinogenesis. Additionally, miR-590-5p suppressed NSCLC progression by directly targeting and regulating METTL3. Importantly, circPUM1 could regulate METTL3 in NSCLC cells through miR-590-5p. In addition, it was also proved circPUM1 silencing impeded tumor growth and glycolysis in the murine xenograft model by regulating miR-590-5p/METTL3 axis. CircPUM1 promoted NSCLC tumor growth and glycolysis through sequestering miR-590-5p and up-regulating METTL3, providing an improved understanding of NSCLC tumorigenesis and a potential therapeutic target for NSCLC therapy.

Lenvatinib Induces AKT/NF-κB Inactivation, Apoptosis Signal Transduction and Growth Inhibition of Non-small Cell Lung Cancer In Vivo.

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer with poor prognosis. Lenvatinib is a multi-kinase inhibitor that has the potential to suppress tumor progression. Our previous study suggested that lenvatinib induces cytotoxicity and apoptosis in CL-1-5-F4 cells in vitro. However, whether lenvatinib suppresses NSCLC progression in vivo remains unclear. Tumor growth inhibition and normal tissue toxicity evaluation following lenvatinib treatment were performed on CL-1-5-F4-bearing mice. Tumor growth calculated by caliper and living cell intensity decreased by lenvatinib treatment as analysed by bioluminescence imaging. Phosphorylation of AKT, NF-κB, and NF-κB downstream proteins involved in tumor progression were reduced by lenvatinib in the tumor tissue. No pathological changes were found in the liver, kidney, and spleen after lenvatinib treatment. Induction of apoptosis and suppression of AKT/NF-κB were associated with lenvatinib-induced inhibition of the progression of NSCLC in vivo.

Circular RNA circ_0001421 contributes to colony formation, migration, invasion and glycolysis of non-small cell lung cancer via the miR-409-3p/TMEM14A axis

IntroductionAccumulating evidence testifies to the considerably significant roles of circular RNAs (circRNAs) in non-small cell lung cancer (NSCLC). This report describes the exploration of the molecular mechanism of circRNA_0001421 (circ_0001421) in NSCLC.Material and methodsThe relative levels of circ_0001421, microRNA-409-3p (miR-409-3p) and transmembrane protein 14A (TMEM14A) were assayed through quantitative real-time polymerase chain reaction (qRT-PCR). Cell colony formation ability was detected by colony formation assay. Transwell assay was exploited for assessing cell migration and invasion. Glycolysis was evaluated via ECAR measurement, glucose consumption, lactate production and protein detection. The protein levels were examined using Western blot. The target combination between miR-409-3p and circ_0001421 or TMEM14A was analyzed by dual-luciferase reporter assay. Xenotransplantation assay was applied for estimating the effect of circ_0001421 on NSCLC in 10 mice.ResultsCirc_0001421 was up-regulated in NSCLC tissues and cells. Down-regulation of circ_0001421 suppressed colony formation, migration, invasion and glycolysis of NSCLC cells. Circ_0001421 could sponge microRNA-409-3p (miR-409-3p) and miR-409-3p inhibition relieved the effects of circ_0001421 knockdown on NSCLC cells. MiR-409-3p targeted transmembrane protein 14A (TMEM14A) and circ_0001421 modulated TMEM14A expression via targeting miR-409-3p. Overexpression of miR-409-3p suppressed NSCLC progression by inhibiting TMEM14A. Circ_0001421 depression restrained tumor growth of NSCLC by the miR-409-3p/TMEM14A axis in vivo.ConclusionsCirc_0001421 facilitated the development of NSCLC via the regulation of the miR-409-3p/TMEM14A axis. Circ_0001421 may be a promising therapeutic target in NSCLC.

Glycogen phosphorylase B promotes cell proliferation and migration through PI3K/AKT pathway in non-small cell lung cancer

Objective Glycogen phosphorylase B (PYGB), the rate-determining enzyme in glycogen degradation, plays a critical role in progression of various tumors. The present study focused on the potential molecular mechanism toward PYGB in non-small cell lung cancer (NSCLC) progression. Methods Expression of PYGB in NSCLC tissues and cell lines was evaluated via quantitative real-time PCR (qRT-PCR), western blot and immunohistochemistry. Cell viability, proliferation and apoptosis were investigated using 3-(4,5-Dimethylthiazol)-2,5-diphenyltetrazolium bromide (MTT) assay, 5-bromo-2-deoxyuridine (BrdU) and flow cytometry, respectively. Cell migration and invasion ability were detected by wound healing and transwell invasion assays, respectively. The in vivo effect of PYGB on NSCLC tumor growth was determined via subcutaneous xenotransplanted tumor model. Results PYGB was upregulated in NSCLC tissues and cell lines, suggesting a poor prognosis in NSCLC patients. In vitro functional assays indicated that knockdown of PYGB suppressed cell viability, proliferation, migration and invasion, while promoted cell apoptosis in NSCLC. Mechanistically, we found that overexpression of PYGB could activate phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway, while these effects were effectively reversed by knockdown of PYGB. In vivo tumorigenesis and PI3K/AKT signaling pathway were also inhibited by PYGB knockdown. Conclusions Knockdown of PYGB suppressed NSCLC progression, suggesting PYGB as a novel biomarker and potential molecular therapeutic target for further investigation in NSCLC.

CircLARP4 Suppresses Cell Proliferation, Invasion and Glycolysis and Promotes Apoptosis in Non-Small Cell Lung Cancer by Targeting miR-135b.

BackgroundCircLARP4 is reported to act as a tumor suppressor in some cancers. However, the detailed roles and molecular basis of circLARP4 in non-small cell lung cancer (NSCLC) tumorigenesis are still unclear. The aim of the study is to explore the potential roles and molecular basis of circLARP4 in NSCLC tumorigenesis.Materials and MethodsqRT-PCR was taken to detect circLARP4 and miR-135b expressions. MTT assay, transwell invasion assay and flow cytometry analysis were applied to evaluate cell proliferation, invasion and apoptosis, respectively. Glycolysis was assessed by measuring hexokinase2 (HK2) expression, glucose consumption and lactate production. Association between circLARP4 and miR-135a was examined by luciferase reporter and RIP assays. The changes of the phosphatase and tension homolog (PTEN)/protein kinase B (AKT)/hypoxia-inducible factor-1α (HIF-1α) pathway were evaluated by Western blot. The nude mouse xenograft models were applied to verify the regulation of circLARP4 in vivo.ResultsCircLARP4 was decreased in NSCLC tissues and cells. CircLARP4 overexpression blocked cell proliferation and invasion, and facilitated apoptosis in NSCLC cells. Meanwhile, circLARP4 overexpression suppressed glycolysis in NSCLC cells, as evidenced by the reduced HK2, glucose consumption and lactate production levels. Further analyses proved a downregulation of miR-135b by circLARP4 in a ceRNA-dependent manner in NSCLC cells. CircLARP4-mediated tumor suppression on NSCLC progression was partially overturned by overexpressing miR-135b. Moreover, we confirmed that circLARP4 had antitumor effect on xenograft tumors and downregulated miR-135b. Furthermore, circLARP4 overexpression inhibited the PTEN/AKT/HIF-1α pathway in NSCLC cells and xenograft tumors by downregulating miR-135b.ConclusionOur findings suggested that circLARP4 suppressed NSCLC progression by sponging miR-135b through inactivation of the PTEN/AKT/HIF-1α pathway, which broadens our understanding concerning the roles of circLARP4 in NSCLC tumorigenesis.

LIMD1-AS1 suppressed non-small cell lung cancer progression through stabilizing LIMD1 mRNA via hnRNP U.

BackgroundNon‐small cell lung cancer (NSCLC) occupies the majority of lung cancer cases and is notorious for the awful prognosis. LIM domains‐containing 1 (LIMD1) is suggested as a tumor suppressor in lung cancer, but its mechanism in NSCLC remains elusive. Present study aimed to uncover the mechanism of LIMD1 in NSCLC.MethodsqRT‐PCR was performed to analyze the level of LIMD1. The functions of LIMD1 in NSCLC cells were evaluated by CCK‐8, EdU, and caspase‐3 activity assays. RIP and pull‐down assays were applied to determine the interaction of LIMD1 with heterogeneous nuclear ribonucleoprotein U (hnRNP U) and LIMD1‐AS1.ResultsLIMD1 was downregulated in NSCLC samples and cells. Functionally, LIMD1 hindered proliferation and drove apoptosis in NSCLC cells. Moreover, long noncoding RNA (lncRNA) LIMD1 antisense RNA 1 (LIMD1‐AS1) was downregulated in NSCLC samples and cell lines. LIMD1‐AS1 knockdown abrogated NSCLC cell growth in vitro and in vivo. Mechanistically, LIMD1‐AS1 stabilized LIMD1 mRNA through interacting with hnRNP U. Rescue experiments suggested that LIMD1‐AS1 repressed NSCLC progression through LIMD1.ConclusionsLIMD1‐AS1 suppressed NSCLC progression through stabilizing LIMD1 mRNA via hnRNP U, providing new thoughts for the improvement of molecular‐targeted therapy for NSCLC.

Long non-coding RNA MIR503HG serves as a tumor suppressor in non-small cell lung cancer mediated by wnt1.

The incidence and death rate of lung cancer has been rising year by year. Non-small cell lung cancer (NSCLC) seriously affects people's health and quality of life. This study was designed to explore the functional role of long-chain non-coding RNA (LncRNA) MIR503HG in the development of NSCLC. The quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) assay was conducted to access the expression level of MIR503HG in NSCLC cell lines and tissues. The Cell Counting Kit-8 (CCK-8) assay, colony formation assay, and flow cytometric analysis were performed to assess the ability of MIR503HG in regulating cell proliferation and apoptosis in NSCLC. Subsequently, Western blotting was used to detect the expression level of Wnt1 in NSCLC. Besides, in vivo tumorigenesis assay was performed in nude mice to examine the ability of MIR503HG in tumor formation. MIR503HG was downregulated in NSCLC. CCK-8 assay and colony formation assay revealed that MIR503HG negatively regulated cell proliferation in NSLCL progression. In addition, MIR503HG promoted cell apoptosis and suppressed cell cycle progression in NSCLC in vitro. MIR503HG inhibited tumor formation in nude mice bearing NSCLC in vivo. MIR503HG downregulated Wnt1 expression in NSCLC. Lon non-coding RNA MIR503HG was downregulated in NSCLC. The over-expression of MIR503HG suppressed cell proliferation and promoted cell apoptosis in vitro and repressed tumorigenesis in vivo. MIR503HG suppressed NSCLC progression via negatively regulating Wnt1 expression.

MicroRNA‑718 serves a tumor‑suppressive role innon‑smallcell lung cancer by directly targeting CCNB1.

MicroRNA-718 (miR-718) serves crucial roles in tumorigenesis and in the progression of a number of cancers. However, the expression profile, specific functions and mechanisms of action of miR-718 in non-small cell lung cancer (NSCLC) are still elusive. The aims of the present study were to quantify the expression of miR-718, determine its biological roles and elucidate the molecular mechanisms responsible for its activities in NSCLC cells. Reverse transcription-quantitative PCR was carried out to assess miR-718 expression in NSCLC tissue samples and cell lines. The Cell Counting Kit-8 assay, flow cytometry, cell migration and invasion assays, and a tumor xenograft experiment were performed to evaluate the effects of miR-718 overexpression on the malignant biological behaviors of NSCLC cells. miR-718 expression was demonstrated to be significantly decreased in NSCLC tissue samples and cell lines. This reduced expression was significantly associated with tumor, node, metastasis stage, tumor size, lymph node metastasis and poor overall survival among patients with NSCLC. Exogenous miR-718 expression suppressed NSCLC cell proliferation, migration and invasion, and promoted apoptosis in vitro; whereas it hindered tumor growth in vivo. Experiments to elucidate the mechanisms involved revealed that miR-718 functions by directly targeting cyclin B1 (CCNB1) mRNA. CCNB1 expression was found to be upregulated in NSCLC and inversely correlated with miR-718 levels. CCNB1 depletion had effects similar to those of miR-718 overexpression in NSCLC cells. Furthermore, restoration of CCNB1 expression attenuated the tumor-suppressive effects of miR-718 overexpression in NSCLC cells. These results indicated that miR-718 suppressed NSCLC progression in vitro and in vivo by directly targeting CCNB1 mRNA, which may indicate a potential target for the diagnosis and treatment of this fatal disease.

Upregulated circRNA ARHGAP10 Predicts an Unfavorable Prognosis in NSCLC through Regulation of the miR-150-5p/GLUT-1 Axis

Non-small-cell lung cancer (NSCLC) is one of the deadliest cancers in the world. Circular RNA (circRNA) has been shown to participate in oncogenesis regulation, including lung cancer. Although the involvement of circRNAs in lung cancer has been reported, the regulatory mechanisms of circRNAs in NSCLC remain poorly understood. Thus, the present study aims at investigating the role of circARHGAP10 in NSCLC progression, which has been observed to be significantly upregulated in both NSCLC tissues and cell lines with profile analysis. A higher expression of circARHGAP10 also leads to a poor prognosis in NSCLC patients with fluorescence in situ hybridization (FISH). Both in vitro and in vivo experiments found that the downregulation of circARHGAP10 suppressed glycometabolism by decreasing GLUT1 expression. Silencing circARHGAP10 also suppressed proliferation and metastasis by targeting the miR-150-5p/GLUT1 axis in NSCLC, which was confirmed with a luciferase reporter assay. Overexpression of GLUT1 or downregulation miR-150-5p will recover NSCLC cell proliferation and metastasis after a knockdown of circARHGAP10. Taken together, these findings demonstrate that circARHGAP10 suppresses NSCLC progression by acting as a miR-150-5p sponge to promote GLUT1 expression. Thus, circARHGAP10 may be a potential target for NSCLC treatment.

Overexpression of microRNA-936 suppresses non-small cell lung cancer cell proliferation and invasion via targeting E2F2.

MicroRNA (miR)-936 has been reported to inhibit the cell cycle and glioma cell proliferation. However, the roles of miR-936 in other human tumors remain largely unknown. In the present study, it was indicated that miR-936 was significantly downregulated in non-small cell lung cancer (NSCLC) tissues compared with adjacent normal tissues by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Results also indicated that miR-936 was downregulated in NSCLC cell lines compared with 16HBE cells. Furthermore, it was demonstrated that overexpression of miR-936 significantly inhibited the proliferation, cell cycle progression and invasion of NSCLC cells. Notably, E2F2 was identified as a target gene of miR-936 in NSCLC cells. The results indicated that E2F2 was upregulated in NSCLC tissues and cell lines, and its expression was negatively correlated with that of miR-936 in NSCLC tissues. Overexpression of miR-936 significantly reduced the protein expression levels of E2F2 in NSCLC cells. Furthermore, restoration of E2F2 rescued the proliferation and invasion of NSCLC cells transfected with miR-936 mimics. To the best of our knowledge, the present findings demonstrated for the first time that miR-936 suppressed NSCLC progression by directly targeting E2F2.

AC-93253 iodide, a novel Src inhibitor, suppresses NSCLC progression by modulating multiple Src-related signaling pathways

BackgroundThe tyrosine kinase Src is involved in the progression of many cancers. Moreover, inhibiting Src activity has been shown to obstruct several signaling pathways regulated by the EGFR. Thus, Src is a valuable target molecule in drug development. The purpose of this study was to identify compounds that directly or indirectly modulate Src to suppress lung cancer cell growth and motility and to investigate the molecular mechanisms underlying the effects of these compounds.MethodsHuman non-small cell lung cancer (NSCLC) cell lines (PC9, PC9/gef, A549, and H1975) with different EGFR statuses were tested by cytotoxicity and proliferation assays after AC-93253 iodide treatment. Src and Src-related protein expression in AC-93253 iodide-treated PC9, PC9/gef, and A549 cells were assessed by western blotting. The effects of AC-93253 iodide on cancer cell colony formation, invasion, and migration were assessed in PC9 and PC9/gef cells. The synergistic effects of gefitinib and AC-93253 iodide were evaluated by combination index (CI)-isobologram analysis in gefitinib-resistant cell lines. The efficacy of AC-93253 iodide in vivo was determined using nude mice treated with either the compound or the vehicle.ResultsAmong the compounds, AC-93253 iodide exhibited the most potent dose-independent inhibitory effects on the activity of Src as well as on that of the Src-related proteins EGFR, STAT3, and FAK. Furthermore, AC-93253 iodide significantly suppressed cancer cell proliferation, colony formation, invasion, and migration in vitro and tumor growth in vivo. AC-93253 iodide sensitized tumor cells to gefitinib treatment regardless of whether the cells were gefitinib-sensitive (PC9) or resistant (H1975 and PC9/gef), indicating that it may exert synergistic effects when used in combination with established therapeutic agents. Our findings also suggested that the inhibitory effects of AC-93253 iodide on lung cancer progression may be attributable to its ability to modulate multiple proteins, including Src, PI3K, JNK, Paxillin, p130cas, MEK, ERK, and EGFR.ConclusionsOur data suggest that AC-93253 iodide inhibits NSCLC cell growth and motility by regulating multiple Src-related pathways. Our findings may facilitate the development of therapeutic strategies and anti-tumor drugs that may be useful for treating lung cancer in the future.

GCIP functions as a tumor suppressor in non-small cell lung cancer by suppressing Id1-mediated tumor promotion.

Grap2 and cyclin D1 interacting protein (GCIP) has been recognized as a putative tumor suppressor, but the molecular mechanisms underlying its anti-tumor properties remain undefined. Here, we report that GCIP is frequently downregulated in non-small cell lung cancer (NSCLC) tissues. Binding assays indicated that inhibitor of DNA binding/differentiation 1 (Id1) interacts with GCIP in the nucleus. Ectopic GCIP expression in the highly invasive NSCLC cell line, H1299, inhibited proliferation, colony formation, invasion and migration, and increased susceptibility to anticancer drugs. Conversely, silencing GCIP expression in the minimally invasive NSCLS cell line, A549, increased proliferation, colony formation, invasion, and migration in vitro, and increased survival and resistance to anticancer drugs. GCIP also suppresses tumorigenicity of NSCLC cells in vivo and GCIP suppresses NSCLC progression is mediated in part by interfering with Id1 signaling, which was confirmed in conditionally induced stable cell lines. In addition, GCIP downregulates the expression of Id1, and GCIP and Id1 are inversely expressed in NSCLC cell lines and specimens. Taken together, these results suggest that GCIP is a potential tumor suppressor in NSCLC and that suppression of Id1-mediated oncogenic properties may be a key mechanism by which GCIP can potently suppress NSCLC tumor progression.