bims-meluca 2021-04-18 papers

Nat Commun. 2021 04 15. 12(1): 2259

SOD1 regulates ribosome biogenesis in KRAS mutant non-small cell lung cancer.

Xiaowen Wang, Hong Zhang, Russell Sapio, Jun Yang, Justin Wong, Xin Zhang, Jessie Y Guo, Sharon Pine, Holly Van Remmen, Hong Li, Eileen White, Chen Liu, Megerditch Kiledjian, Dimitri G Pestov, X F Steven Zheng.

SOD1 is known as the major cytoplasmic superoxide dismutase and an anticancer target. However, the role of SOD1 in cancer is not fully understood. Herein we describe the generation of an inducible Sod1 knockout in KRAS-driven NSCLC mouse model. Sod1 knockout markedly reduces tumor burden in vivo and blocks growth of KRAS mutant NSCLC cells in vitro. Intriguingly, SOD1 is enriched in the nucleus and notably in the nucleolus of NSCLC cells. The nuclear and nucleolar, not cytoplasmic, form of SOD1 is essential for lung cancer cell proliferation. Moreover, SOD1 interacts with PeBoW complex and controls its assembly necessary for pre-60S ribosomal subunit maturation. Mechanistically, SOD1 regulates co-localization of PeBoW with and processing of pre-rRNA, and maturation of cytoplasmic 60S ribosomal subunits in KRAS mutant lung cancer cells. Collectively, our study unravels a nuclear SOD1 function essential for ribosome biogenesis and proliferation in KRAS-driven lung cancer.

DOI: https://doi.org/10.1038/s41467-021-22480-x

J Thorac Dis. 2021 Mar;13(3): 1769-1784

Enhanced expression of FGF19 predicts poor prognosis in patients with non-small cell lung cancer.

Jia Chen, Jingjing Shao, Aiguo Shen, Xinghua Zhu, Xunlei Zhang, Hui Sun, Sheng Wei, Yang Ling.

Background: Lung cancer is one of the most common cancers and a leading cause of cancer-related death worldwide. Although many treatment options exist for lung cancer, some patients still suffer postoperative recurrence, and a consequent reduction of overall survival (OS). Our study aimed to investigate the correlation of FGF19 expression with the clinicopathological features and survival outcomes of non-small cell lung cancer (NSCLC) patients.
Methods: Bioinformatics analysis was conducted using the data from The Cancer Genome Atlas (TCGA) database to distinguish between the FGF19 levels of tumor and normal tissue and to determine their correlation with the OS. A total of 187 NSCLC patients who underwent radical resection of lung cancer were enrolled, and tissues were collected to determine FGF19 expression by immunohistochemistry (IHC) assay. Clinicopathological features including the survival date were collected for detailed research.
Results: According to the analysis based on the TCGA database, we found that the NSCLC tissues exhibited enhanced FGF19 messenger RNA (mRNA) expression and that the FGF19 mRNA levels correlated with shorter OS in NSCLC patients. IHC staining indicated that 88 (47.1%) patients had high FGF19 expression and 99 (52.9%) patients had low FGF19 expression. Meanwhile, survival data showed that high FGF19 expression was correlated with reduced OS (P<0.001). Moreover, both the univariate analysis and the forward stepwise multivariate Cox regression revealed that high FGF19 expression was an independent prognostic factor for decreased OS (P=0.001).
Conclusions: The expression of FGF19 is significantly upregulated in NSCLC, and the overexpression of FGF19 is correlated with poor OS, especially in lung adenocarcinoma (LUAD) cases. FGF19 might serve as a potential biomarker for predicting poor OS in NSCLC patients.

Keywords: FGF19; immunohistochemistry (IHC); non-small cell lung cancer (NSCLC); prognosis

DOI: https://doi.org/10.21037/jtd-21-126

Exp Ther Med. 2021 Jun;21(6): 581

Metformin prevents PFKFB3-related aerobic glycolysis from enhancing collagen synthesis in lung fibroblasts by regulating AMPK/mTOR pathway.

Ci-Jun Tang, Ji Xu, Hai-Yan Ye, Xue-Bin Wang.

Aerobic glycolysis has been shown to contribute to the abnormal activation of lung fibroblasts with excessive collagen deposition in lipopolysaccharide (LPS)-induced pulmonary fibrosis. Targeting aerobic glycolysis in lung fibroblasts might therefore be considered as a promising therapeutic approach for LPS-induced pulmonary fibrosis. In the present study, the aim was to investigate whether metformin, a widely used agent for treating type 2 diabetes, could alleviate LPS-induced lung fibroblast collagen synthesis and its potential underlying mechanisms. Different concentrations of metformin were used to treat the human lung fibroblast MRC-5 cells after LPS challenge. Indicators of aerobic glycolysis in MRC-5 cells were detected by measuring glucose consumption and lactate levels in culture medium in addition to lactate dehydrogenase activity in cellular lysates. The glucose consumption, lactate levels and the lactate dehydrogenase activity were measured respectively using colorimetric/fluorometric and ELISA kits. The effects of metformin in AMP-activated protein kinase (AMPK) activation was assessed by mitochondrial complex I activity kits. Collagen I, α-smooth muscle actin (α-SMA) and collagen III were used as markers of collagen synthesis, which was measured using western blotting, whereas phosphorylated (p-) AMPK, AMPK, 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3) and mTOR were detected by western blotting. Metformin significantly decreased mitochondrial complex I activity and upregulated the expression of p-AMPK/AMPK protein in a concentration-dependent manner. Furthermore, the aerobic glycolysis mediated by PFKFB3 and collagen synthesis in LPS-treated MRC-5 cells was gradually inhibited with increasing concentrations of metformin. However, this inhibitory role of metformin on PFKFB3-meditaed aerobic glycolysis and collagen synthesis was prevented by treatments with 3BDO and compound C, which are specific mTOR activator and AMPK inhibitor, respectively. Taken together, the findings from this study suggested that metformin may prevent PFKFB3-associated aerobic glycolysis from enhancing collagen synthesis in lung fibroblasts via regulating the AMPK/mTOR pathway.

Keywords: lipopolysaccharide; lung fibroblast; metformin; pulmonary fibrosis

DOI: https://doi.org/10.3892/etm.2021.10013

Int J Oncol. 2021 Jun;pii: 28. [Epub ahead of print]58(6):

Metformin impairs cisplatin resistance effects in A549 lung cancer cells through mTOR signaling and other metabolic pathways.

Ana Paula Morelli, Tharcísio Citrângulo Tortelli, Isadora Carolina Betim Pavan, Fernando Riback Silva, Daniela Campos Granato, Guilherme Francisco Peruca, Bianca Alves Pauletti, Romênia Ramos Domingues, Rosangela Maria Neves Bezerra, Leandro Pereira De Moura, Adriana Franco Paes Leme, Roger Chammas, Fernando Moreira Simabuco.

Lung cancer is the leading cause of cancer‑associated death worldwide and exhibits intrinsic and acquired therapeutic resistance to cisplatin (CIS). The present study investigated the role of mTOR signaling and other signaling pathways after metformin (MET) treatment in control and cisplatin‑resistant A549 cells, mapping pathways and possible targets involved in CIS sensitivity. MTT, flow cytometry, clonogenic assay, western blotting, proteomic analysis using the Stable Isotope Labeling by Amino acids in Cell culture (SILAC) approach and reverse transcription‑quantitative PCR were performed. The results revealed that CIS treatment induced mTOR signaling pathway overactivation, and the mTOR status was restored by MET. MET and the mTOR inhibitor rapamycin (RAPA) decreased the viability in control and resistant cells, and decreased the cell size increase induced by CIS. In control cells, MET and RAPA decreased colony formation after 72 h and decreased IC50 values, potentiating the effects of CIS. Proteomics analysis revealed important pathways regulated by MET, including transcription, RNA processing and IL‑12‑mediated signaling. In CIS‑resistant cells, MET regulated the apoptotic process, oxidative stress and G2/M transition. Annexin 4 (ANXA4) and superoxide dismutase 2 (SOD2), involved in apoptosis and oxidative stress, respectively, were chosen to validate the SILAC analysis and may represent potential therapeutic targets for lung cancer treatment. In conclusion, the chemosensitizing and antiproliferative effects of MET were associated with mTOR signaling and with potential novel targets, such as ANXA4 and SOD2, in human lung cancer cells.

DOI: https://doi.org/10.3892/ijo.2021.5208

Front Oncol. 2021 ;11 561247

Prognostic Impact of PCK1 Protein Kinase Activity-Dependent Nuclear SREBP1 Activation in Non-Small-Cell Lung Carcinoma.

Fei Shao, Xueli Bian, Juhong Wang, Daqian Xu, Wei Guo, Hongfei Jiang, Gaoxiang Zhao, Lei Zhu, Shuai Wang, Dongming Xing, Yibo Gao, Jie He, Zhimin Lu.

Metabolic enzymes can perform non-metabolic functions and play critical roles in the regulation of a variety of important cellular activities. Phosphoenolpyruvate carboxykinase 1 (PCK1), a gluconeogenesis enzyme, was recently identified as an AKT-regulated protein kinase that phosphorylates INSIG1/2 to promote nuclear SREBP1-dependent lipogenesis. However, the relationship of this regulation with the progression of non-small-cell lung carcinoma (NSCLC) is unclear. Here, we demonstrate that epidermal growth factor receptor (EGFR) activation induces AKT-dependent PCK1 pS90, PCK1-mediated INSIG1 pS207/INSIG2 pS151, and nuclear SREBP1 accumulation in NSCLC cells. In addition, the expression levels of AKT pS473, PCK1 pS90, INSIG1 pS207/INSIG2 pS151, and nuclear SREBP1 are higher in 451 analyzed human NSCLC specimens than in their adjacent normal tissues and positively correlated with each other in the tumor specimens. Furthermore, the expression levels of PCK1 pS90, INSIG1 pS207/INSIG2 pS151, and nuclear SREBP1 are associated with TNM stage and progression in NSCLC. Importantly, levels of PCK1 pS90 or INSIG1 pS207/INSIG2 pS151 are positively correlated with poor prognosis in NSCLC patients, and the combined expression value of the PCK1 and INSIG1/2 phosphorylation has a better prognostic value than that of each individual protein phosphorylation value and is an independent prognostic marker for NSCLC. These findings reveal the role of PCK1-mediated nuclear SREBP1 activation in NSCLC progression and highlight the potential to target the protein kinase activity of PCK1 for the diagnosis and treatment of human NSCLC.

Keywords: INSIG1/2; PCK1; SREBP1; immunohistochemistry; lipogenesis; non-small-cell lung carcinoma; phosphorylation; prognosis

DOI: https://doi.org/10.3389/fonc.2021.561247

Cancer Cell Int. 2021 Apr 15. 21(1): 219

Establishment and validation of a prognostic signature for lung adenocarcinoma based on metabolism-related genes.

Zhihao Wang, Kidane Siele Embaye, Qing Yang, Lingzhi Qin, Chao Zhang, Liwei Liu, Xiaoqian Zhan, Fengdi Zhang, Xi Wang, Shenghui Qin.

BACKGROUND: Given that dysregulated metabolism has been recently identified as a hallmark of cancer biology, this study aims to establish and validate a prognostic signature of lung adenocarcinoma (LUAD) based on metabolism-related genes (MRGs).
METHODS: The gene sequencing data of LUAD samples with clinical information and the metabolism-related gene set were obtained from The Cancer Genome Atlas (TCGA) and Molecular Signatures Database (MSigDB), respectively. The differentially expressed MRGs were identified by Wilcoxon rank sum test. Then, univariate cox regression analysis was performed to identify MRGs that related to overall survival (OS). A prognostic signature was developed by multivariate Cox regression analysis. Furthermore, the signature was validated in the GSE31210 dataset. In addition, a nomogram that combined the prognostic signature was created for predicting the 1-, 3- and 5-year OS of LUAD. The accuracy of the nomogram prediction was evaluated using a calibration plot. Finally, cox regression analysis was applied to identify the prognostic value and clinical relationship of the signature in LUAD.
RESULTS: A total of 116 differentially expressed MRGs were detected in the TCGA dataset. We found that 12 MRGs were most significantly associated with OS by using the univariate regression analysis in LUAD. Then, multivariate Cox regression analyses were applied to construct the prognostic signature, which consisted of six MRGs-aldolase A (ALDOA), catalase (CAT), ectonucleoside triphosphate diphosphohydrolase-2 (ENTPD2), glucosamine-phosphate N-acetyltransferase 1 (GNPNAT1), lactate dehydrogenase A (LDHA), and thymidylate synthetase (TYMS). The prognostic value of this signature was further successfully validated in the GSE31210 dataset. Furthermore, the calibration curve of the prognostic nomogram demonstrated good agreement between the predicted and observed survival rates for each of OS. Further analysis indicated that this signature could be an independent prognostic indicator after adjusting to other clinical factors. The high-risk group patients have higher levels of immune checkpoint molecules and are therefore more sensitive to immunotherapy. Finally, we confirmed six MRGs protein and mRNA expression in six lung cancer cell lines and firstly found that ENTPD2 might played an important role on LUAD cells colon formation and migration.
CONCLUSIONS: We established a prognostic signature based on MRGs for LUAD and validated the performance of the model, which may provide a promising tool for the diagnosis, individualized immuno-/chemotherapeutic strategies and prognosis in patients with LUAD.

Keywords: Lung adenocarcinoma; Metabolism‐related genes; Prognostic; The Cancer Genome Atlas

DOI: https://doi.org/10.1186/s12935-021-01915-x