Downregulation of p38 MAPK Activation and Radiation-Sensitive 52 Expression Enhances 5-Fluorouracil and Erlotinib-Induced Cytotoxicity in Human Lung Squamous Cells

Pharmacology ◽  
2021 ◽  
pp. 1-14
Author(s):  
Jen-Chung Ko ◽  
Jyh-Cheng Chen ◽  
Chia-Li Wei ◽  
Li-Ling Liu ◽  
Chin-Cheng Chien ◽  
...  

<b><i>Introduction:</i></b> 5-Fluorouracil (5-FU) is used to treat various cancers, including non-small-cell lung cancer (NSCLC). It inhibits nucleotide synthesis and induces single- and double-strand DNA breaks. In the homologous recombination pathway, radiation-sensitive 52 (Rad52) plays a crucial role in DNA repair by promoting the annealing of complementary single-stranded DNA and stimulating Rad51 recombinase activity. Erlotinib (Tarceva) is a selective epidermal growth factor receptor tyrosine kinase inhibitor with clinical activity against NSCLC cells. However, whether the combination of 5-FU and erlotinib has synergistic activity against NSCLC cells is unknown. <b><i>Methods:</i></b> After the 5-FU and/or erlotinib treatment, the expressions of Rad52 mRNA were determined by quantitative real-time polymerase chain reaction analysis. Protein levels of Rad52 and phospho-p38 MAPK were determined by Western blot analysis. We used specific Rad52 or p38 MAPK small interfering RNA and p38 MAPK inhibitor (SB2023580) to examine the role of p38 MAPK-Rad52 signal in regulating the chemosensitivity of 5-FU and/or erlotinib. Cell viability was assessed by MTS assay and trypan blue exclusion assay. <b><i>Results:</i></b> In 2 squamous cell carcinoma cell lines, namely, H520 and H1703, 5-FU reduced Rad52 expression in a p38 MAPK inactivation-dependent manner. Enhancement of p38 MAPK activity by transfection with MKK6E (a constitutively active form of MKK6) vector increased the Rad52 protein level and cell survival by 5-FU. However, in human lung bronchioloalveolar cell adenocarcinoma A549 cells, 5-FU reduced Rad52 expression and induced cytotoxicity independent of p38 MAPK. Moreover, 5-FU synergistically enhanced the cytotoxicity and cell growth inhibition of erlotinib in NSCLC cells; these effects were associated with Rad52 downregulation and p38 MAPK inactivation in H520 and H1703 cells. <b><i>Conclusion:</i></b> The results provide a rationale for combining 5-FU and erlotinib in lung cancer treatment.

Author(s):  
Elham Hoveizi ◽  
Fatemeh Fakharzadeh Jahromi

Background: The development of effective anticancer drugs is a significant health issue. Previous studies showed that members of the benzimidazole family have anticancer effects on several cancers Objectives: The present study investigated the cytotoxic effect of flubendazole on A549 human lung cancer cells. Methods: The A549 cells were treated with flubendazole at 1, 2, 5, and 10 µM concentrations for three days. Cell viability was measured by the MTT assay and Acridine orange staining. Also, the expressions of P62 and Beclin -1 were analyzed by qRT-PCR analysis. Results: Cell viability of A549 cells, in a concentration-dependent manner, showed significant differences between the treatment and control groups, and the IC50 value was determined to be 2 µM. Also, flubendazole reduced the expression of P62 and increased the expression of Beclin 1 in treated cells. Conclusions: Flubendazole induces cell death in A549 cells in a dose and time-dependent manner and can offer new factors in lung cancer therapeutic strategies.


2020 ◽  
Vol 19 (17) ◽  
pp. 2091-2096 ◽  
Author(s):  
Hui Fang ◽  
Hongmei Ji

Background and Purpose: The fruit of Fructus liquidambaris, which is recently being used for cancer treatment, has a history to be used as a traditional medicine in China for thousands of years. Material and Methods: Ten kg of dried F. liquidambaris was obtained with 70% alcohol-water solution under reflux for three times. The condensed extract was obtained from petroleum ether, ethyl acetate and N-butyl alcohol, respectively. Ethyl acetate extract was subjected to silica gel column, Sephadex LH-20, ODS column chromatography and RP-HPLC column chromatography to yield a new compound (1). The structure was identified through intensive analysis of NMR and MS spectra. The antitumor mechanism of the furanocoumarin A on human lung cancer A549 cells was confirmed by detecting the apoptosis-related proteins. Result: Furanocoumarin A (1), a novel furanocoumarin constituent was isolated and identified from F. Liquidambaris. The IC50 value of furanocoumarin A on A549 cell lines was 65.28±5.36µM obtained by the method of MTT. The compound could induce the apoptosis of A549 cells by inducing 21.5% early apoptosis and 32.4% late apoptosis at the concentration of 60µmol/L. Western blot analysis indicated that protein expressions of p53, caspase 3 and Bax increased in a dose-dependent manner between the concentrations from 40 to 80µM. The protein expression of Bcl-2 decreased the concentration of 60 and 80μM. The ratio of Bcl-2 to Bax was inversely proportional to the dose concentration. Conclusion: Furanocoumarin A could be a novel anticancer agent from herbal medicine.


2013 ◽  
Vol 25 (4) ◽  
pp. 939-954 ◽  
Author(s):  
Matheus Augusto de Bittencourt Pasquali ◽  
Daniel Pens Gelain ◽  
Fares Zeidán-Chuliá ◽  
André Simões Pires ◽  
Juciano Gasparotto ◽  
...  

2020 ◽  
Vol 11 (7) ◽  
Author(s):  
ZhaoMin Lin ◽  
ZhaoYang Wang ◽  
XueWen Zhou ◽  
Ming Zhang ◽  
DongFang Gao ◽  
...  

AbstractA series of fluorescent thiazole–pyrazoline derivatives was synthesized and their structures were characterized by 1H NMR, 13C NMR, and HRMS. Biological evaluation demonstrated that these compounds could effectively inhibit the growth of human non-small cell lung cancer (NSCLC) A549 cells in a dose- and time-dependent manner in vitro and inhibit tumor growth in vivo. The structure–activity relationship (SAR) of the compounds was analyzed. Further mechanism research revealed they could induce autophagy and cell cycle arrest while had no influence on cell necrosis. Compound 5e inhibited the activity of mTOR via FKBP12, which could be reversed by 3BDO, an mTOR activator and autophagy inhibitor. Compound 5e inhibited growth, promoted autophagy of A549 cells in vivo. Moreover, compound 5e showed good selectivity with no influence on normal vascular endothelial cell growth and the normal chick embryo chorioallantoic membrane (CAM) capillary formation. Therefore, our research provides potential lead compounds for the development of new anticancer drugs against human lung cancer.


2021 ◽  
Vol 54 (1) ◽  
Author(s):  
Xiang-Bo Jia ◽  
Quan Zhang ◽  
Lei Xu ◽  
Wen-Jian Yao ◽  
Li Wei

Abstract Background Leaves of the natural plant lotus are used in traditional Chinese medicine and tea production. They are rich in flavonoids. Methods In this study, lotus leaf flavonoids (LLF) were applied to human lung cancer A549 cells and human small cell lung cancer cells H446 in vitro to verify the effect of LLF on apoptosis in these cells through the ROS/p38 MAPK pathway. Results LLF had no toxic effect on normal cells at concentrations up to 500 µg/mL, but could significantly inhibit the proliferation of A549 cells and H446 cells. Flow cytometry showed that LLF could induce growth in A549 cells. We also found that LLF could increase ROS and MDA levels, and decrease SOD activity in A549 cells. Furthermore, qRT-PCR and western blot analyses showed that LLF could upregulate the expression of p38 MAPK (p-p38 MAPK), caspase-3, caspase-9, cleaved caspase-3, cleaved caspase-9 and Bax and downregulate the expression of Cu/Zn SOD, CAT, Nrf2, NQO1, HO-1, and Bcl-2 in A549 cells. Results of HPLC showed that LLF mainly contain five active substances: kaempferitrin, hyperoside, astragalin, phloridzin, and quercetin. The apoptosis-inducing effect of LLF on A549 cells came from these naturally active compounds. Conclusions We have shown in this study that LLF is a bioactive substance that can induce apoptosis in A549 cells in vitro, and merits further research and development.


2021 ◽  
Vol 22 (12) ◽  
pp. 6606
Author(s):  
Tobias Mechelke ◽  
Felix Wittig ◽  
Robert Ramer ◽  
Burkhard Hinz

Tissue factor (TF) plays an important role in the progression and angiogenesis of tumor cells. The present study investigated the mechanism of interleukin-1β (IL-1β)-induced TF expression in A549 lung cancer cells. Based on mRNA and protein analyses, including appropriate inhibitor experiments, IL-1β was shown to induce TF expression in a time-dependent manner, mediated by IL-1 receptor-dependent phosphorylation of the mitogen-activated protein kinases (MAPK) p38, p42/44 and c-jun N-terminal kinase (JNK), as well as the Src kinase and the epidermal growth factor receptor (EGFR). Thereby, inhibition of EGFR transactivation by the Src inhibitor PP1 or direct EGFR inhibition by the EGFR tyrosine kinase inhibitor (TKI) erlotinib led to a reduction of IL-1β-induced TF expression and to a suppression of p42/44 MAPK and EGFR activation, while IL-1β-induced p38 MAPK and JNK activation remained unchanged. A knockdown of EGFR by siRNA was associated with decreased IL-1β-mediated p42/44 MAPK activation, which was no longer inhibitable by erlotinib. Concentration-dependent inhibition of IL-1β-induced TF expression was also observed in the presence of gefitinib and afatinib, two other EGFR TKIs. In summary, our results suggest that IL-1β leads to increased TF formation in lung cancer cells via both Src/EGFR/p42/44 MAPK-dependent and EGFR-independent signaling pathways, with the latter mediated via p38 MAPK and JNK.


2020 ◽  
Author(s):  
Aleksandr Ianevski ◽  
Rouan Yao ◽  
Svetlana Biza ◽  
Eva Zusinaite ◽  
Andres Männik ◽  
...  

AbstractCombination therapies have become a standard for the treatment for HIV and HCV infections. They are advantageous over monotherapies due to better efficacy and reduced toxicity, as well as the ability to prevent the development of resistant viral strains and to treat viral co-infections. Here, we identify several new synergistic combinations against emerging and re-emerging viral infections in vitro. We observed synergistic activity of nelfinavir with investigational drug EIDD-2801 and convalescent serum against SARS-CoV-2 infection in human lung epithelial Calu-3 cells. We also demonstrated synergistic activity of vemurafenib combination with emetine, homoharringtonine, gemcitabine, or obatoclax against echovirus 1 infection in human lung epithelial A549 cells. We also found that combinations of sofosbuvir with brequinar and niclosamide were synergistic against HCV infection in hepatocyte derived Huh-7.5 cells, whereas combinations of monensin with lamivudine and tenofovir were synergistic against HIV-1 infection in human cervical TZM-bl cells. Finally, we present an online resource that summarizes novel and known antiviral drug combinations and their developmental status. Overall, the development of combinational therapies could have a global impact improving the preparedness and protection of the general population from emerging and re-emerging viral threats.


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