Investigation of mediastinal lymph node dissection in clinical stage IA pure-solid non-small cell lung cancer patients.

OBJECTIVE: To explore the independent predictors of pathological mediastinal lymph node (pN2) metastasis in clinical stage IA (cIA) pure-solid non-small cell lung cancer (NSCLC) patients, and to find an appropriate method of mediastinal lymph node dissection. METHODS: This study retrospectively evaluated 533 cIA pure-solid NSCLC patients who underwent radical resection of lung cancer (lobectomy combined with systematic lymph node dissection) from January 2014 to December 2016. The relationship between clinicopathological characteristics and pN2 metastasis was analyzed, and the independent predictors of pN2 metastasis were determined by univariate and multivariate logistic regression analysis. We defined the new factor Y as composed of preoperative cT, CEA, and NSE. RESULTS: There were 72 cases (13.5%) of pN2 metastasis in cIA pure-solid NSCLC patients. Preoperative clinical tumor diameter (cT), serum CEA level, serum NSE level, and pathological status of station 10 lymph nodes were independent predictors of pN2 metastasis. Patients with cT ≤ 21.5 mm, CEA ≤ 3.85 ng/mL, NSE ≤ 13.40 ng/mL and negative station 10 lymph node group showed lower rates of pN2 metastasis. The new factor Y was an independent predictor of pN2 metastasis. Only 3 (2.1%) of 143 patients in the Y low-risk group showed pN2 metastasis. CONCLUSION: For patients with low risk of pN2 metastasis, it might be feasible to take lobe-specific lymph node sampling or systematic lymph node sampling. As for those with high risk of pN2 metastasis, systematic lymph node dissection would be recommended.

Proliferation, apoptosis and invasion of human lung cancer cells are associated with NFATc1.

The expression of nuclear factor of activated T cells c1 (NFATc1) is closely associated with the progression of numerous types of cancer. When NFATc1 expression becomes dysregulated in some types of cancer, this alteration can promote malignant transformation and thereby progression of cancer. NFATc1 expression has been demonstrated to be upregulated in lung cancer cells. This suggests that knockdown of NFATc1 in lung cancer cells may be a therapeutic marker for the treatment of cancer. In the present study, the effects of NFATc1 on the proliferation, apoptosis, invasion and migration of NCI-H1299 and A549 lung cancer cell lines were explored. Lentivirus infection was used to establish a cell model of NFATc1 knockdown in A549 and NCI-H1299 lung cancer cells. Reverse transcription-quantitative PCR was subsequently performed to detect NFATc1 expression in these human lung cancer cells. MTT, wound healing, colony formation and Transwell invasion assays, and flow cytometry were then performed to measure the proliferation, invasion, apoptosis and cell cycle of the cells. Finally, western blot analysis was performed to investigate the mechanism underlying the involvement of NFATc1 in these processes. NFATc1 knockdown was found to significantly inhibit the proliferation, clone formation, migration and invasion of the cells. Furthermore, the cell cycle was arrested at the G1 phase and the expression levels of the target proteins located downstream in the signaling pathway, namely CDK4, c-Myc, ERK, p38 and N-cadherin, were decreased. Following NFATc1 knockdown, the percentages of apoptotic cells were increased, and the expression levels of Bax, cleaved caspase-3 and E-cadherin were also increased. Taken together, the results of the present study suggested that NFATc1 serves an oncogenic role in lung cancer. In terms of the underlying mechanism, NFATc1 promoted the proliferation of lung cancer cells by inhibiting the MAPK and epithelial-to-mesenchymal transition signaling pathways, suggesting that NFATc1 may be a novel target for therapeutic intervention for the treatment of lung cancer.

PIGF and Flt-1 on the surface of macrophages induces the production of TGF-ß1 by polarized tumor-associated macrophages to promote lung cancer angiogenesis.

BACKGROUND: The interaction between tumor cells and tumor microenvironment is a necessary condition for promoting the metastasis of malignant tumors. METHODS: Two different transwell culture systems were interfered with by recombinant factor placental growth factor (re-PIGF) and the re-PIGF + transforming growth factor-ß1 (TGF-ß1)-neutralizing antibody (anti-TGF-ß1). We performed immunofluorescence, flow cytometry and enzyme linked immunosorbent assay (ELISA) to analyze the expression of PIGF, fms-like tyrosine kinase-1 (Flt-1), macrophage marker F4/80 +, macrophage M2 marker CD163+ and TGF-ß1 in vitro. Meanwhile, cell viability assay and optical microscope assay were conducted to explore the cell viability and vascularization ability of human umbilical vein endothelial cells (HUVECs). RESULTS: Re-PIGF increased the expression of PIGF in A549 cells and the expression of Flt-1 in BM-Mac cells, and significantly enhanced the ability of bone marrow-derived macrophages (BM-Mac) to transform into macrophages. At the same time, re-PIGF increased the expression of cytokine TGF-ß1 in A549 cells/BM-Mac transwell culture system. On the contrary, re-PIGF + anti-TGF-ß1 inhibited the expression of Flt-1 in BM-Mac cells and inhibited the ability of BM-Mac cells to transform into macrophages. Finally, re-PIGF + anti-TGF-ß1 reduced the cell viability and angiogenesis of HUVECs. CONCLUSION: The surface molecule PIGF of lung cancer cells could bind to the receptor Flt-1 on the surface of macrophages, thereby increasing the production of TGF-ß1, and ultimately promoting the formation of angiogenesis in lung cancer.

The Functional Characterization of Epigenetically Related lncRNAs Involved in Dysregulated CeRNA-CeRNA Networks Across Eight Cancer Types.

Numerous studies have demonstrated that lncRNAs could compete with other RNAs to bind miRNAs, as competing endogenous RNAs (ceRNAs), to regulate each other. On the other hand, ceRNAs were found to be recurrently dysregulated in cancer status. However, limited studies considered the upstream epigenetic regulatory factors that disrupted the normal competing mechanism. In the present study, we constructed the lncRNA-associated dysregulated ceRNA networks across eight cancer types. lncRNAs in the individual dysregulated network and pan-cancer core dysregulated ceRNA subnetwork were found to play more important roles than mRNAs. Integrating lncRNA methylation profiles, we identified 49 epigenetically related (ER) lncRNAs involved in the dysregulated ceRNA networks, including 18 epigenetically activated (EA) lncRNAs, 18 epigenetically silenced (ES) lncRNAs, and 13 rewired ER lncRNAs across eight cancer types. Furthermore, we evaluated the epigenetic regulating patterns of these lncRNAs and screened nine pan-cancer ER lncRNAs (six EA and three ES lncRNAs). The nine lncRNAs were found to regulate the cancer hallmarks by competing with mRNAs. Moreover, we found that integrating the expression and methylation profiles of the nine lncRNAs could predict cancer incidence in eight cancer types robustly and the cancer outcome of several cancer types. These results provide an improved understanding of methylation regulation to ceRNA and offer novel potential molecular therapeutic targets for the diagnosis and prognosis across different cancer types.

CircKEAP1 Suppresses the Progression of Lung Adenocarcinoma via the miR-141-3p/KEAP1/NRF2 Axis.

BACKGROUND: Lung cancer is the leading cause of death from cancer, and lung adenocarcinoma (LUAD) is the most common form. Despite the great advances that has been made in the diagnosis and treatment for LUAD, the pathogenesis of LUAD remains unclear. In this study, we aimed to identify the function of circKEAP1 derived from the exon of KEAP1 in LUAD. METHODS: The expression profiles of circRNAs in LUAD tissues and adjacent non-tumor tissues were analyzed by Agilent Arraystar Human CircRNA microarray. The levels and prognostic values of circKEAP1 in tissues and cancer cell lines were determined by quantitative real-time PCR (qRT-PCR). Subsequently, the effects of circKEAP1 on tumor growth were investigated by functional experiments in vitro and in vivo. Mechanistically, the dual luciferase reporter assay, RNA pull-down, and RNA immunoprecipitation experiments were performed to confirm the interaction between circKEAP1 and miR-141-3p in LUAD. RESULTS: We found circKEAP1 was significantly downregulated in LUAD tissues and repressed tumor growth both in vitro and in vivo. Mechanistically, circKEAP1 competitively binds to miR-141-3p and relive miR-141-3p repression for its host gene, which activated the KEAP1/NRF2 signal pathway, and finally suppresses the tumor progress. Our findings suggest that circKEAP1 inhibits LUAD progression through circKEAP1/miR-141-3p/KEAP1 axis and it may serve as a novel method for the treatment of LUAD.

MiR-139-5p Targetedly Regulates YAF2 and Mediates the AKT/P38 MAPK Signaling Pathway to Alleviate the Metastasis of Non-Small Cell Lung Cancer Cells and Their Resistance Against Cisplatin.

OBJECTIVE: To explore relevant mechanisms of miR-139-5p in alleviating the metastasis of non-small cell lung cancer cells (NSCLC) and their resistance against cisplatin. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot (WB) assays were carried out to determine the protein levels of miR-139-5p and YAF2, and cisplatin (DDP)-resistant NSCLC cell strains were established. Subsequently, an MTT assay was employed to evaluate the viability of the cell strains, a Transwell assay to evaluate cell invasion activity, and flow cytometry to analyze cell apoptosis rate. Finally, a Western blot assay was carried out to determine the protein levels of P-PI3K and p-p38. RESULTS: NSCLC tissues showed lower miR-139-5p expression and higher YAF2 expression than paracancerous tissues and human normal lung epithelial cells, and miR-139-5p was related to the prognosis of NSCLC patients. Overexpression of miR-139-5p or knock-down of YAF2 inhibited the proliferation and invasion of NSCLC cells and induced their apoptosis. Additionally, the dual-luciferase reporter assay verified a targeting relationship between miR-139-5p and YAF2. Overexpression of miR-139-5p and knockdown of YAF2 reversed the resistance of A549/DDP cells against DDP, inactivated p38 and Akt proteins, and inhibited the AKT/p38 MAPK signaling pathway. Furthermore, inhibiting the AKT/p38 MAPK signaling pathway with MK2206 resisted the effects of knock-down of miR-139-5p on DDP resistance in NSCLC cells. CONCLUSION: MiR-139-5p targetedly regulates YAF2 and mediates the AKT/p38 MAPK signaling pathway to alleviate the metastasis of NSCLC cells and their resistance against cisplatin, which may be a novel target for improving the therapeutic effect on NSCLC.

A multicenter single-arm trial of sintilimab in combination with chemotherapy for neoadjuvant treatment of resectable esophageal cancer (SIN-ICE study).

BACKGROUND: Preoperative chemotherapy or chemoradiotherapy is the standard treatment for resectable esophageal cancer (EC); however, it is associated with increased postoperative complications and mortality. Recently, Immune Checkpoint inhibitors have been incorporated in the treatment of advanced EC. Its role in the preoperative setting has not been established yet. In this multicenter, single-arm study, we evaluated the efficacy and safety of neoadjuvant therapy with sintilimab in combination with chemotherapy in treating EC. METHODS: Patients received neoadjuvant therapy with 3 cycles of sintilimab 200 mg Q3W in combination with platinum-based chemotherapy. Surgery was performed within 4-6 weeks after neoadjuvant therapy. The primary endpoints of the trial were pathological complete response (pCR) and safety. RESULTS: A total of 23 patients (21 men and 2 women) were enrolled. Surgery was completed in 17 participants, with 16 achieving R0 resection and 1 had R1 resection, 5 participants refused surgery. One patient progressed prior to surgery. Twenty one patients (91%) had significant improvement in their dysphagia following treatment as assessed by Stooler's criteria. The majority of patients who underwent resection have a good pathological response and downstaging rate was 76.5% (13/17). A pCR was achieved in 6 cases (6/17, 35.3%) and major pathological response (MPR) in 9 cases (9/17, 52.9%). The main preoperative adverse events (AEs) were vomiting (13/23, 56.5%), leukopenia (12/23, 52.2%), neutropenia (9/23, 39.1%), and malaise (8/23, 34.8%). Immune-related AEs were mild and included hypothyroidism (2/23, 8.7%) and rash (4/23, 17.4%). The incidence of ≥ grade 3 treatment related AEs was 30.4% (7/23). There were no ≥ grade 4 AEs. CONCLUSIONS: Sintilimab in combination with chemotherapy in the neoadjuvant treatment of EC is safe and lead to a high pCR. Therefore, further testing is warranted.

Effects of wogonoside on invasion and migration of lung cancer A549 cells and angiogenesis in xenograft tumors of nude mice.

BACKGROUND: Lung cancer is the most prevalent and deadly tumors around the world. Here we aimed to investigate the effect of wogonoside (also called baicalin) on the invasion and migration of lung cancer A549 cells and angiogenesis in xenograft tumors in nude mice. METHODS: A549 cells of lung cancer were treated with different doses of wogonoside. After 24 h, CCK8 was used to detect the survival rate of cells. The non-toxic doses of wogonoside (0, 10, 25, and 50 µM) were selected for subsequent experiments. Transwell and scratch assays were used to detect invasion and migration. The number of microtubule nodules was detected by microtubule formation experiment, and the expressions of VEGF, E-cadherin, N-cadherin, and Vimentin were detected by Western blotting. BALB/c nude mice were subcutaneously injected with lung cancer A549 cells to establish the xenograft model, followed by intraperitoneal injection of 80 mg/kg of wogonoside. After 30 days, tumor volume was measured, and the levels of VEGF and vimentin were detected with immunohistochemistry. The level of CD34 was determined by flow sorting. RESULTS: A549 cell survival decreased in a concentration-dependent manner, with the survival rate significantly reduced when the concentration of wogonoside exceeded 100 µM (P<0.05). A549 cell invasion and the number of microtubule nodules were significantly lower in the wogonoside 20 µM and the wogonoside 50 µM groups (P<0.05) compared with the wogonoside 0 µM group, while the rate of scratch closure and the protein levels of VEGF, N-cadherin, and Vimentin were all significantly reduced (P<0.05), and the expression level of E-cadherin was significantly increased (P<0.05). Compared with the control group, the tumor volumes of wogonoside (80 mg/kg) treated mice were significantly reduced after 30 days (P<0.05), and the levels of VEGF and vimentin positive cells were significantly reduced (P<0.05), as was the level of CD34 (P<0.05). CONCLUSIONS: Wogonoside can inhibit the invasion and migration of lung cancer A549 cells and angiogenesis of xenograft tumors in nude mice.

CUTL1 induces epithelial-mesenchymal transition in non-small cell lung cancer.

The homeobox transcription factor CUTL1 has been associated with cellular proliferation and cell cycle progression, and CUTL1 functions as an oncogene. The aim of the present study was to investigate whether CUTL1 participates in epithelial-mesenchymal transition (EMT). The expression levels of CUTL1, E-cadherin, N-cadherin and Snail were determined by immunohistochemistry assay, immunofluorescence assay or real-time quantitative reverse transcription PCR. Their roles in non-small cell lung cancer (NSCLC) were assessed by functional analyses. Protein expression was detected by western blot analysis. The CUTL1 expression levels are higher in non-small cell lung cancer (NSCLC) tissues. High CUTL1 expression in NSCLC is associated with the mesenchymal-like phenotype. Mechanistically, CUTL1 upregulates transforming growth factor ß receptor I (TßR-I) expression, and the TßR-I inhibitor SB431542 abolishes EMT elicited by ectopic CUTL1 expression. Transforming growth factor ß (TGF-ß) signaling is essential for CUTL1-induced EMT in NSCLC cells. CUTL1 is downstream of TGF-ß signaling and CUTL1 is involved in the expression of the TßR-I. This study indicates that CUTL1 may be a potential target for anti-lung cancer therapy.

miR-455-5p promotes cell growth and invasion by targeting SOCO3 in non-small cell lung cancer.

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer. miR-455-5p has increased expression and the ability to promote tumorigenesis in certain cancers. However, the role of miR-455-5p in NSCLC has not been sufficiently investigated. SOCS3 (suppressor of cytokine signaling 3), an important tumor suppressor, is often aberrantly inactivated in various tumors, but it is currently unclear whether SOCO3 is a target of miR-455-5p. In the present study, we investigated the role of miR-455-5p in NSCLC. We found that the expression of miR-455-5p was up-regulated in NSCLC tumor tissues compared to corresponding noncancerous tissues, and its expression was correlated with metastasis and tumor node metastasis in NSCLC tissue. We then showed that miR-455-5p promoted migration, invasion and proliferation in NSCLC cell lines. Additionally, we also found that SOCS3 was the direct target gene of miR-455-5p. Consistently, the expression of SOCS3 was negatively correlated with the expression of miR-455-5p in NSCLC tissues. We further show that aberrant miR-455-5p expression is partially controlled by activated ERK signaling in NSCLC. Therefore, miR-455-5p could enhance the growth and metastasis of NSCLC by inhibiting SOCS3, thus providing a potential molecular therapeutic target for the treatment of NSCLC patients.

Pterostilbene Inhibits the Growth of Human Esophageal Cancer Cells by Regulating Endoplasmic Reticulum Stress.

BACKGROUND/AIMS: Pterostilbene (PTE), a natural dimethylated resveratrol analog from blueberries, is known to have diverse pharmacological activities, including anticancer properties. In this study, we investigated the anticancer activity of PTE against human esophageal cancer cells both in vitro and in vivo and explored the role of endoplasmic reticulum (ER) stress (ERS) signaling in this process. METHODS: Cell viability, the apoptotic index, Caspase 3 activity, adhesion, migration, reactive oxygen species (ROS) levels, and glutathione (GSH) levels were detected to explore the effect of PTE on human EC109 esophageal cancer cells. Furthermore, siRNA transfection and a chemical inhibitor were employed to confirm the role of ERS. RESULTS: PTE treatment dose- and time-dependently decreased the viability of human esophageal cancer EC109 cells. PTE also decreased tumor cell adhesion, migration and intracellular GSH levels while increasing the apoptotic index, Caspase 3 activity and ROS levels, which suggest the strong anticancer activity of PTE. Furthermore, PTE treatment increased the expression of ERS-related molecules (GRP78, ATF6, p-PERK, p-eIF2α and CHOP), upregulated the pro-apoptosis-related protein PUMA and downregulated the anti-apoptosis-related protein Bcl-2 while promoting the translocation of cytochrome c from mitochondria to cytosol and the activation of Caspase 9 and Caspase 12. The downregulation of ERS signaling by CHOP siRNA desensitized esophageal cancer cells to PTE treatment, whereas upregulation of ERS signaling by thapsigargin (THA) had the opposite effect. N-Acetylcysteine (NAC), a ROS scavenger, also desensitized esophageal cancer cells to PTE treatment. CONCLUSIONS: Overall, the results indicate that PTE is a potent anti-cancer pharmaceutical against human esophageal cancer, and the possible mechanism involves the activation of ERS signaling pathways.

FOSL2 positively regulates TGF-ß1 signalling in non-small cell lung cancer.

Fos-related antigen 2 (FRA-2/FOSL2) belongs to the AP-1 transcription factor family. Although FOSL2 has been shown to be involved in diverse physiological and pathological processes, very little is known about the signalling pathways that regulate FOSL2 expression and the mechanisms of FOSL2 function. Here, we show that FOSL2 expression is regulated by TGF-ß1 and that FOSL2 is required for TGF-ß1-induced migration. We demonstrate that FOSL2 interacts with Smad3 in vitro and in vivo and thus up-regulates TGF-ß1-induced signalling responses. Mechanistically, FOSL2 promotes P300 binding to Smad3 and the acetylation of Smad3 by P300. Furthermore, we show that the expression of FOSL2 correlates with activated Smad3 expression in clinical non-small cell lung cancer (NSCLC) samples. In summary, the present study indicates that FOSL2 facilitates TGF-ß1-induced migration by interaction with Smad3 in NSCLC and suggests FOSL2 as a potential therapeutic target for NSCLC.