scholarly journals Liver Kinase B1 Expression Promotes Phosphatase Activity and Abrogation of Receptor Tyrosine Kinase Phosphorylation in Human Cancer Cells

2013 ◽  
Vol 289 (3) ◽  
pp. 1639-1648 ◽  
Author(s):  
Imoh S. Okon ◽  
Kathleen A. Coughlan ◽  
Ming-Hui Zou
Keyword(s):  
Lung Cancer ◽  
Growth Factor ◽  
Tyrosine Kinase ◽  
Cancer Cells ◽  
Cell Lines ◽  
Cancer Cell ◽  
Receptor Tyrosine Kinase ◽  
Egf Receptor ◽  
Liver Kinase B1 ◽  
Kinase Phosphorylation

Aberrant receptor tyrosine kinase phosphorylation (pRTK) has been associated with diverse pathological conditions, including human neoplasms. In lung cancer, frequent liver kinase B1 (LKB1) mutations correlate with tumor progression, but potential links with pRTK remain unknown. Heightened and sustained receptor activation was demonstrated by LKB1-deficient A549 (lung) and HeLaS3 (cervical) cancer cell lines. Depletion (siRNA) of endogenous LKB1 expression in H1792 lung cancer cells also correlated with increased pRTK. However, ectopic LKB1 expression in A549 and HeLaS3 cell lines, as well as H1975 activating-EGF receptor mutant lung cancer cell resulted in dephosphorylation of several tumor-enhancing RTKs, including EGF receptor, ErbB2, hepatocyte growth factor receptor (c-Met), EphA2, rearranged during transfection (RET), and insulin-like growth factor I receptor. Receptor abrogation correlated with attenuation of phospho-Akt and increased apoptosis. Global phosphatase inhibition by orthovanadate or depletion of protein tyrosine phosphatases (PTPs) resulted in the recovery of receptor phosphorylation. Specifically, the activity of SHP-2, PTP-1β, and PTP-PEST was enhanced by LKB1-expressing cells. Our findings provide novel insight on how LKB1 loss of expression or function promotes aberrant RTK signaling and rapid growth of cancer cells.

scholarly journals Splice variants of the extracellular region of RON receptor tyrosine kinase in lung cancer cell lines identified by PCR and sequencing

BMC Cancer ◽  
2017 ◽  
Vol 17 (1) ◽  
Author(s):  
Soundararajan Krishnaswamy ◽  
Abdul Khader Mohammed ◽  
Gyanendra Tripathi ◽  
Majed S. Alokail ◽  
Nasser M. Al-Daghri
Keyword(s):  
Lung Cancer ◽  
Tyrosine Kinase ◽  
Cell Lines ◽  
Cancer Cell ◽  
Receptor Tyrosine Kinase ◽  
Splice Variants ◽  
Cancer Cell Lines ◽  
Lung Cancer Cell ◽  
Extracellular Region ◽  
Ron Receptor

scholarly journals Differential Effects of Combined ATR/WEE1 Inhibition in Cancer Cells

Cancers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 3790
Author(s):  
Gro Elise Rødland ◽  
Sissel Hauge ◽  
Grete Hasvold ◽  
Lilli T. E. Bay ◽  
Tine T. H. Raabe ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Cell Viability ◽  
Cancer Treatment ◽  
Cancer Cells ◽  
Cell Lines ◽  
Cancer Cell ◽  
Combined Treatment ◽  
Cancer Cell Lines ◽  
Variable Extent ◽  
Synergistic Induction

Inhibitors of WEE1 and ATR kinases are considered promising for cancer treatment, either as monotherapy or in combination with chemo- or radiotherapy. Here, we addressed whether simultaneous inhibition of WEE1 and ATR might be advantageous. Effects of the WEE1 inhibitor MK1775 and ATR inhibitor VE822 were investigated in U2OS osteosarcoma cells and in four lung cancer cell lines, H460, A549, H1975, and SW900, with different sensitivities to the WEE1 inhibitor. Despite the differences in cytotoxic effects, the WEE1 inhibitor reduced the inhibitory phosphorylation of CDK, leading to increased CDK activity accompanied by ATR activation in all cell lines. However, combining ATR inhibition with WEE1 inhibition could not fully compensate for cell resistance to the WEE1 inhibitor and reduced cell viability to a variable extent. The decreased cell viability upon the combined treatment correlated with a synergistic induction of DNA damage in S-phase in U2OS cells but not in the lung cancer cells. Moreover, less synergy was found between ATR and WEE1 inhibitors upon co-treatment with radiation, suggesting that single inhibitors may be preferable together with radiotherapy. Altogether, our results support that combining WEE1 and ATR inhibitors may be beneficial for cancer treatment in some cases, but also highlight that the effects vary between cancer cell lines.

scholarly journals Encapsulation of Nedaplatin in Novel PEGylated Liposomes Increases Its Cytotoxicity and Genotoxicity against A549 and U2OS Human Cancer Cells

Pharmaceutics ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 863 ◽  
Author(s):  
Salma El-Shafie ◽  
Sherif Ashraf Fahmy ◽  
Laila Ziko ◽  
Nada Elzahed ◽  
Tamer Shoeib ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Dna Damage ◽  
Small Cell Lung Cancer ◽  
Cancer Cells ◽  
Cell Line ◽  
Cell Lines ◽  
Cancer Cell ◽  
Cell Lung Cancer ◽  
Small Cell ◽  
Small Cell Lung

Following the discovery of cisplatin over 50 years ago, platinum-based drugs have been a widely used and effective form of cancer therapy, primarily causing cell death by inducing DNA damage and triggering apoptosis. However, the dose-limiting toxicity of these drugs has led to the development of second and third generation platinum-based drugs that maintain the cytotoxicity of cisplatin but have a more acceptable side-effect profile. In addition to the creation of new analogs, tumor delivery systems such as liposome encapsulated platinum drugs have been developed and are currently in clinical trials. In this study, we have created the first PEGylated liposomal form of nedaplatin using thin film hydration. Nedaplatin, the main focus of this study, has been exclusively used in Japan for the treatment of non-small cell lung cancer, head and neck, esophageal, bladder, ovarian and cervical cancer. Here, we investigate the cytotoxic and genotoxic effects of free and liposomal nedaplatin on the human non-small cell lung cancer cell line A549 and human osteosarcoma cell line U2OS. We use a variety of assays including ICP MS and the highly sensitive histone H2AX assay to assess drug internalization and to quantify DNA damage induction. Strikingly, we show that by encapsulating nedaplatin in PEGylated liposomes, the platinum uptake cytotoxicity and genotoxicity of nedaplatin was significantly enhanced in both cancer cell lines. Moreover, the enhanced platinum uptake as well as the cytotoxic/antiproliferative effect of liposomal nedaplatin appears to be selective to cancer cells as it was not observed on two noncancer cell lines. This is the first study to develop PEGylated liposomal nedaplatin and to demonstrate the superior cell delivery potential of this product.

Sign in / Sign up

Export Citation Format

Share Document