bims-meluca 2019-02-17 papers

Exp Lung Res. 2019 Feb 10. 1-7

Hyperbaric oxygen rescues lung cancer cells from chemical hypoxia-induced low differentiation and apoptosis resistance.

Wang Y, Qi Y, Wei X, Chen S, Jia N, Zhou Q, Zhang S, Gui S, Wang Y.

Hypoxia induces vigorous growth and a higher malignant phenotype in solid tumors. Hyperoxic treatment using hyperbaric oxygen (HBO) has previously been shown as a highly effective method to attenuate hypoxia. We aimed to investigate the effect of HBO on hypoxia-induced malignancy of lung cancer cells. Cobalt chloride (CoCl2) was used to induce chemical hypoxia in lung cancer cell line A549. Hypoxic inducible factor-1α (HIF-1α) expression, lactate dehydrogenase (LDH) activity, migration and invasion capacity, expression profiles of epithelial-mesenchymal transition (EMT) markers and apoptotic markers were assessed in CoCl2-treated A549 cells, with or without HBO treatment. Chemical hypoxia caused by CoCl2 resulted in high LDH activity, increased migration and invasion, decreased E-cadherin/N-cadherin ratio, enhanced EMT phenotype, higher Bcl-2/Bax ratio and elevated GRP78 expression. HBO treatment could significantly attenuate hypoxia-induced LDH activity, migration and invasion, restore hypoxia-reduced E-cadherin/N-cadherin ratio and EMT phenotype, as well as hypoxia-induced Bcl-2/Bax ratio, and repress GRP78 expression. HBO could serve as a reliable adjuvant treatment targeting the hypoxia microenvironment in solid tumors.

Keywords: Hyperbaric oxygen; apoptosis; differentiation; lung cancer

DOI: https://doi.org/10.1080/01902148.2019.1571124

J Exp Clin Cancer Res. 2019 Feb 12. 38(1): 71

Autophagy inhibition potentiates the anti-angiogenic property of multikinase inhibitor anlotinib through JAK2/STAT3/VEGFA signaling in non-small cell lung cancer cells.

Liang L, Hui K, Hu C, Wen Y, Yang S, Zhu P, Wang L, Xia Y, Qiao Y, Sun W, Fei J, Chen T, Zhao F, Yang B, Jiang X.

BACKGROUND: The efficacy and safety of multikinase inhibitor anlotinib have been confirmed in the treatment of advanced non-small cell lung cancer (NSCLC). However, the direct functional mechanisms of tumor lethality mediated by anlotinib were not fully elucidated, and the underlying mechanisms related to resistance remain largely elusive.METHODS: Cell viability, colony formation, apoptosis and tumor growth assays were performed to examine the effect of anlotinib on lung cancer cells in vitro and in vivo. The punctate patterns of LC3-I/II were detected by confocal microscopy. HUVECs motility was detected using Transwell and scratch wound-healing assay. To visualize the microvessels, tubular formation assay was performed. The expression of LC3-I/II and beclin-1 and the changes of JAK2/STAT3/VEGFA pathway were detected by western blotting. The VEGFA levels in tumor supernatant were measured by ELISA.
RESULTS: Anlotinib treatment decreased cell viability and induced apoptosis in Calu-1 and A549 cells. Moreover, anlotinib induced human lung cancer cell autophagy in a dose- and time-dependent manner. Blocking autophagy enhanced the cytotoxicity and anti-angiogenic ability of anlotinib as evidenced by HUVECs migration, invasion, and tubular formation assay. Co-administration of anlotinib and chloroquine (CQ) further reduced VEGFA level in the tumor supernatant, compared with that of anlotinib or CQ treatment alone. When autophagy was induced by rapamycin, the JAK2/STAT3 pathway was activated and VEGFA was elevated, which was attenuated after deactivating STAT3 by S3I-201. Further in vivo studies showed that anlotinib inhibited tumor growth, induced autophagy and suppressed JAK2/STAT3/VEGFA pathway, and CQ enhanced this effect.
CONCLUSION: Anlotinib induced apoptosis and protective autophagy in human lung cancer cell lines. Autophagy inhibition further enhanced the cytotoxic effects of anlotinib, and potentiated the anti-angiogenic property of anlotinib through JAK2/STAT3/VEGFA signaling.

Keywords: Anlotinib; Anti-angiogenesis; Apoptosis; Autophagy; NSCLC; VEGFA

DOI: https://doi.org/10.1186/s13046-019-1093-3

EBioMedicine. 2019 Feb 09. pii: S2352-3964(19)30087-8. [Epub ahead of print]

Inhibition of oncogenic Src induces FABP4-mediated lipolysis via PPARγ activation exerting cancer growth suppression.

Hua TNM, Kim MK, Vo VTA, Choi JW, Choi JH, Kim HW, Cha SK, Park KS, Jeong Y.

BACKGROUND: c-Src is a driver oncogene well-known for tumorigenic signaling, but little for metabolic function. Previous reports about c-Src regulation of glucose metabolism prompted us to investigate its function in other nutrient modulation, particularly in lipid metabolism.METHODS: Oil-red O staining, cell growth assay, and tumor volume measurement were performed to determine lipid amount and growth inhibitory effect of treatments in lung cancer cells and xenograft model. Gene expression was evaluated by immunoblotting and relative RT-PCR. Transcriptional activity of peroxisome proliferator-activated receptor gamma (PPARγ) was assessed by luciferase assay. Reactive oxygen species (ROS) was measured using ROS sensing dye. Oxygen consumption rate was evaluated by Seahorse XF Mito Stress Test. Clinical relevance of candidate proteins was examined using patient samples and public database analysis.
FINDINGS: Inhibition of Src induced lipolysis and increased intracellular ROS. Src inhibition derepressed PPARγ transcriptional activity leading to induced expression of lipolytic gene fatty acid binding protein (FABP) 4 which accompanies reduced lipid droplets and decreased tumor growth. The reverse correlation of Src and FABP4 was confirmed in pair-matched lung cancer patient samples, and further analysis using public datasets revealed upregulation of lipolytic genes is associated with better prognosis of cancer patients.
INTERPRETATION: This study provides an insight of how oncogenic factor Src concurrently regulates both cellular signaling pathways and metabolic plasticity to drive cancer progression. FUND: National Research Foundation of Korea and Korea Health Industry Development Institute.

Keywords: FABP4; Lipid; Lung cancer; PPARγ; Src

DOI: https://doi.org/10.1016/j.ebiom.2019.02.015

Mol Cell Biochem. 2019 Feb 11.

LCAL1 enhances lung cancer survival via inhibiting AMPK-related antitumor functions.

Li JY, Luo ZQ.

Lung cancer is one of the most common cancers and has been the most common cause of cancer deaths for several decades. Recently, lung cancer-associated lncRNA 1 (LCAL1) has been identified to be overexpressed in lung cancer tissues, while inhibiting LCAL1 expression has shown potential to inhibiting lung cancer growth. However, the molecular mechanism between LCAL1 and lung cancer cell survival remains poorly understood. In the present study, we provided the first evidence that LCAL1 may support lung cancer survival via inhibiting the activity of AMP-activated protein kinase (AMPK). According to our results, LCAL1 may physically interact with the catalytic subunit of tumor suppressor AMPK, prevent AMPK activation by upstream kinase (liver kinase B1), and thus inhibit the downstream AMPK signaling network. Our study revealed that overexpressed LCAL1 may induce aerobic glycolysis in lung cancer cells through AMPK/HIF1α axis, enhance protein synthesis through AMPK/mTOR/S6K axis, and suppress autophagic cell death through AMPK/ULK1 pathway. All these alterations supported rapid proliferation of lung cancer cells, while knockdown of LCAL1 expression demonstrated the potential of inhibiting lung cancer growth by reversing the tumorigenic phenotypes triggered by the loss of AMPK activity, and could become a promising therapeutic strategy for lung cancer treatment.

Keywords: AMPK; LCAL1; LncRNA; Lung cancer

DOI: https://doi.org/10.1007/s11010-019-03507-w

Apoptosis. 2019 Feb 14.

Autophagy inhibition with chloroquine reverts paclitaxel resistance and attenuates metastatic potential in human nonsmall lung adenocarcinoma A549 cells via ROS mediated modulation of β-catenin pathway.

Datta S, Choudhury D, Das A, Mukherjee DD, Dasgupta M, Bandopadhyay S, Chakrabarti G.

Paclitaxel is one of the most commonly used drugs for the treatment of nonsmall cell lung cancer (NSCLC). However acquired resistance to paclitaxel, epithelial to mesenchymal transition and cancer stem cell formation are the major obstacles for successful chemotherapy with this drug. Some of the major reasons behind chemoresistance development include increased ability of the cancer cells to survive under stress conditions by autophagy, increased expression of drug efflux pumps, tubulin mutations etc. In this study we found that inhibition of autophagy with chloroquine prevented development of paclitaxel resistance in A549 cells with time and potentiated the effect of paclitaxel by increased accumulation of superoxide-producing damaged mitochondria, with elevated ROS generation, it also increased the apoptotic rate and sub G0/ G1 phase arrest with time in A549 cells treated with paclitaxel and attenuated the metastatic potential and cancer stem cell population of the paclitaxel-resistant cells by ROS mediated modulation of the Wnt/β-catenin signaling pathway, thereby increasing paclitaxel sensitivity. ROS here played a crucial role in modulating Akt activity when autophagy process was hindered by chloroquine, excessive ROS accumulation in the cell inhibited Akt activity. In addition, chloroquine pre-treatment followed by taxol (10 nM) treatment did not show significant toxicity towards non-carcinomas WI38 cells (lung fibroblast cells). Thus autophagy inhibition by CQ pre-treatment can be used as a fruitful strategy to combat the phenomenon of paclitaxel resistance development as well as metastasis in lung cancer.

Keywords: Autophagy; Chloroquine; EMT; Paclitaxel-resistance; ROS; β-Catenin

DOI: https://doi.org/10.1007/s10495-019-01526-y