scholarly journals Dynamic analysis of pulsed cisplatin identifies effectors of resistance in lung adenocarcinoma

2019 ◽  
Author(s):  
Jordan F. Hastings ◽  
Alvaro Gonzalez-Rajal ◽  
Jeremy Z.R. Han ◽  
Rachael A. McCloy ◽  
Yolande E.I. O’Donnell ◽  
...  

AbstractIdentification of clinically viable strategies for overcoming resistance to platinum chemotherapy in lung adenocarcinoma has been hampered by inappropriately tailored in vitro assays of drug response. Therefore, using a pulse model that closely recapitulates the in vivo pharmacokinetics of platinum therapy, we profiled cisplatin-induced signalling, DNA damage and apoptotic responses across a panel of lung adenocarcinoma cell lines. By coupling this data with real-time, single cell imaging of cell cycle and apoptosis, we show that TP53 mutation status influenced the mode of cisplatin induced cell cycle arrest, but could not predict cisplatin sensitivity. In contrast, P70S6K-mediated signalling promoted resistance by increasing p53/p63 and p21 expression, reducing double-stranded DNA breaks and apoptosis. Targeting P70S6K sensitised both TP53 wildtype and null lines to cisplatin, but not TP53 mutant lines. In summary, using in vitro assays that mimic in vivo pharmacokinetics identified P70S6K as a robust mediator of cisplatin resistance and highlighted the importance of considering somatic mutation status when designing patient-specific combination therapies.

2020 ◽  
Author(s):  
Alvaro Gonzalez-Rajal ◽  
Rachael McCloy ◽  
Max Nobis ◽  
Kamila A Marzec ◽  
Venessa Chin ◽  
...  

AbstractInnate resistance to platinum-based chemotherapies has significantly reduced their impact in lung adenocarcinoma. We previously used a pulse-based in vitro assay to unveil targetable signalling pathways associated with this resistant phenotype (Hastings et al., 2020). Here we advanced this model system and identify a non-genetic mechanism of resistance that drives recovery and regrowth in a subset of cells. Using RNAseq and a suite of biosensors to track single cell fates both in vitro and in vivo, we identified that early S phase cells have a greater capacity to repair damage over multiple generations. In contrast, cells in G1, late S or those treated with PARP inhibitors, were unable to sufficiently repair the damage and underwent prolonged S/G2 phase arrest and senescence. These data indicate that there is a fundamental non-genetic mechanism of resistance in lung adenocarcinoma that is dependent on the cell cycle stage at the time of cisplatin exposure.


2018 ◽  
Vol 2018 ◽  
pp. 1-8
Author(s):  
Quanxiang Liu ◽  
Yang Song ◽  
Xianliang Duan ◽  
Yuan Chang ◽  
Jianping Guo

Background. MicroRNAs (miRs) have been implicated in the development and progression of osteosarcoma. Here, we aimed to illustrate the important role of miR-92a on the regulation of OS development which may help to establish a novel strategy for OS diagnosis and treatment. Materials and Methods. Cell viability was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell cycle and apoptosis were assessed by flow cytometry with PI and PI/Annexin-V stain, respectively. The expression of proteins was examined by western blot. qPCR was used to detect the expression of RNA. Cell migration was assayed with transwell assay. Results. MiR-92a inhibited the proliferation and the migration of OS in vitro and reduced the volume of the tumour in vivo. Further, miR-92a enhanced cisplatin sensitivity of OS. MiR-92a directly targeted Notch1. Conclusion. Together, our results indicate that miR-92a inhibited cell growth, migration, and enhanced cisplatin sensitivity of OS cell by targeting Notch1.


2020 ◽  
Author(s):  
Ru-nan Zhang ◽  
Dong-mei Wu ◽  
Li-ping Wu ◽  
Guo-wei Gao

Abstract Background: Emerging studies have attested that long noncoding RNAs (lncRNAs) predominantly functioned in carcinogenesis of multiple developing human tumors. The current research aimed at probing the underlying participation and mechanisms of LINC00337 in lung adenocarcinoma.Methods: Here we analyzed TCGA and GTEx datasets and chose LINC00337 as research object. Cell proliferation, cell apoptosis, cell cycle, and invasion were detected in gain and loss experiment of LINC00337 both in vitro and in vivo. Moreover, RNA pull-down, luciferase reporter assays, western blotting analysis, rescue experiment were performed to investigate underlying molecular mechanisms of LINC00337 function. Results: LINC00337 was remarkably increased in lung adenocarcinoma. Also, LINC00337 knock-down was unraveled to repress cell invasion and proliferation as well as cell cycle, and gear up apoptosis in lung adenocarcinoma in vitro and in vivo. With respect to mechanism, LINC00337 knock-down boosted miR-1285-3p to be expressed and then restrained YTHDF1 to be expressed post-transcriptionally. Crucially, both miR-1285-3p decrement and YTHDF1 overexpression successfully countered the influence on cell proliferation, invasion and apoptosis caused by LINC00337 shRNA.Conclusions: These results suggest that LINC00337 acted as an oncogenic lncRNA, targeting miR-1285-3p and regulating YTHDF1 expression, to promote the progression of lung adenocarcinoma.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ru-nan Zhang ◽  
Dong-mei Wu ◽  
Li-ping Wu ◽  
Guo-wei Gao

Abstract Background Emerging studies have shown that long noncoding RNAs (lncRNAs) predominantly function in the carcinogenesis of multiple developing human tumors. The current study aimed to investigate the underlying mechanisms of LINC00337 in lung adenocarcinoma. Methods We analyzed TCGA and GTEx datasets and chose LINC00337 as the research object. Cell proliferation, cell apoptosis, cell cycle, migration, and invasion were detected in the gain and loss experiments of LINC00337 both in vitro and in vivo. Moreover, RNA pull-down, luciferase reporter assays, western blotting analysis, and rescue experiments were performed to investigate the underlying molecular mechanisms of LINC00337 function. Results LINC00337 expression was remarkably upregulated in lung adenocarcinoma. In addition, LINC00337 knockdown was shown to repress cell migration, invasion, and proliferation, as well as the cell cycle, and gear up apoptosis in lung adenocarcinoma in vitro and in vivo. With respect to the mechanism, LINC00337 knockdown boosted miR-1285-3p expression and then restrained YTHDF1 expression post-transcriptionally. Crucially, both miR-1285-3p decrement and YTHDF1 overexpression successfully reversed the influence on cell proliferation, migration, invasion, and apoptosis caused by LINC00337 shRNA. Conclusions These results suggest that LINC00337 acts as an oncogenic lncRNA, targeting miR-1285-3p and regulating YTHDF1 expression, to promote the progression of lung adenocarcinoma.


2021 ◽  
Vol 11 ◽  
Author(s):  
Xu Han ◽  
Jixiang Wu ◽  
Yajun Zhang ◽  
Jianxiang Song ◽  
Zhan Shi ◽  
...  

Previous studies have shown that long intergenic non-protein coding RNA 00518 (LINC00518) are essential for the cell growth and metastasis of human cancer. However, the role of LINC00518 in lung adenocarcinoma (LUAD) is still unknown. This research put emphasis on the function of LINC00518 on the cell growth of LUAD. The lncRNA, miRNA and mRNA expression were measured by using qRT-PCR. Protein levels were measured by using Western blotting. CCK-8, colony formation assays and transwell assay were performed to evaluate the cell proliferation ability and invasion. Bioinformatic analysis and luciferase reporter assays were chosen to confirm the mechanism of LINC00518 in LUAD. We found that LINC00518 was highly expressed in LUAD specimens and the high-expression was negatively correlated with the overall survival rates. This finding was also proved in the LUAD cell lines. Through a series of in vitro and in vivo experiments, we proved that LICN00518 promoted the cell growth of LUAD by regulating the cell cycle. Moreover, LICN00518 upregulated the expression of MECP2 by mutagenesis of miR-185-3p. The results suggested that LICN00518 could be used as a survival indicator and potential therapeutic target for LUAD patients.


eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Jordan F Hastings ◽  
Alvaro Gonzalez Rajal ◽  
Sharissa L Latham ◽  
Jeremy ZR Han ◽  
Rachael A McCloy ◽  
...  

The identification of clinically viable strategies for overcoming resistance to platinum chemotherapy in lung adenocarcinoma has previously been hampered by inappropriately tailored in vitro assays of drug response. Therefore, using a pulse model that closely mimics the in vivo pharmacokinetics of platinum therapy, we profiled cisplatin-induced signalling, DNA-damage and apoptotic responses across a panel of human lung adenocarcinoma cell lines. By coupling this data to real-time, single-cell imaging of cell cycle and apoptosis we provide a fine-grained stratification of response, where a P70S6K-mediated signalling axis promotes resistance on a TP53 wildtype or null background, but not a mutant TP53 background. This finding highlights the value of in vitro models that match the physiological pharmacokinetics of drug exposure. Furthermore, it also demonstrates the importance of a mechanistic understanding of the interplay between somatic mutations and the signalling networks that govern drug response for the implementation of any consistently effective, patient-specific therapy.


eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Alvaro Gonzalez Rajal ◽  
Kamila A Marzec ◽  
Rachael A McCloy ◽  
Max Nobis ◽  
Venessa Chin ◽  
...  

We previously used a pulse-based in vitro assay to unveil targetable signalling pathways associated with innate cisplatin resistance in lung adenocarcinoma (Hastings et al., 2020). Here we advanced this model system and identified a non-genetic mechanism of resistance that drives recovery and regrowth in a subset of cells. Using RNAseq and a suite of biosensors to track single cell fates both in vitro and in vivo, we identified that early S phase cells have a greater ability to maintain proliferative capacity, which correlated with reduced DNA damage over multiple generations. In contrast, cells in G1, late S or those treated with PARP/RAD51 inhibitors, maintained higher levels of DNA damage and underwent prolonged S/G2 phase arrest and senescence. Combined with our previous work, these data indicate that there is a non-genetic mechanism of resistance in human lung adenocarcinoma that is dependent on the cell cycle stage at the time of cisplatin exposure.


2019 ◽  
Vol 19 (3) ◽  
pp. 365-374 ◽  
Author(s):  
Yang Liu ◽  
Jingyin Zhang ◽  
Shuyun Feng ◽  
Tingli Zhao ◽  
Zhengzheng Li ◽  
...  

Objective: The aim of this study is to investigate the inhibitory effect of camptothecin derivative 3j on Non-Small Cell Lung Cancer (NSCLCs) cells and the potential anti-tumor mechanisms. Background: Camptothecin compounds are considered as the third largest natural drugs which are widely investigated in the world and they suffered restriction because of serious toxicity, such as hemorrhagic cystitis and bone marrow suppression. Methods: Using cell proliferation assay and S180 tumor mice model, a series of 20(S)-O-substituted benzoyl 7- ethylcamptothecin compounds were screened and evaluated the antitumor activities in vitro and in vivo. Camptothecin derivative 3j was selected for further study using flow cytometry in NSCLCs cells. Cell cycle related protein cyclin A2, CDK2, cyclin D and cyclin E were detected by Western Blot. Then, computer molecular docking was used to confirm the interaction between 3j and Topo I. Also, DNA relaxation assay and alkaline comet assay were used to investigate the mechanism of 3j on DNA damage. Results: Our results demonstrated that camptothecin derivative 3j showed a greater antitumor effect in eleven 20(S)-O-substituted benzoyl 7-ethylcamptothecin compounds in vitro and in vivo. The IC50 of 3j was 1.54± 0.41 µM lower than irinotecan with an IC50 of 13.86±0.80 µM in NCI-H460 cell, which was reduced by 8 fold. In NCI-H1975 cell, the IC50 of 3j was 1.87±0.23 µM lower than irinotecan (IC50±SD, 5.35±0.38 µM), dropped by 1.8 fold. Flow cytometry analysis revealed that 3j induced significant accumulation in a dose-dependent manner. After 24h of 3j (10 µM) treatment, the percentage of NCI-H460 cell in S-phase significantly increased (to 93.54 ± 4.4%) compared with control cells (31.67 ± 3.4%). Similarly, the percentage of NCI-H1975 cell in Sphase significantly increased (to 83.99 ± 2.4%) compared with control cells (34.45 ± 3.9%) after treatment with 10µM of 3j. Moreover, increased levels of cyclin A2, CDK2, and decreased levels of cyclin D, cyclin E further confirmed that cell cycle arrest was induced by 3j. Furthermore, molecular docking studies suggested that 3j interacted with Topo I-DNA and DNA-relaxation assay simultaneously confirmed that 3j suppressed the activity of Topo I. Research on the mechanism showed that 3j exhibited anti-tumour activity via activating the DNA damage response pathway and suppressing the repair pathway in NSCLC cells. Conclusion: Novel camptothecin derivative 3j has been demonstrated as a promising antitumor agent and remains to be assessed in further studies.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Shuiyan Wu ◽  
You Jiang ◽  
Yi Hong ◽  
Xinran Chu ◽  
Zimu Zhang ◽  
...  

Abstract Background T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive disease with a high risk of induction failure and poor outcomes, with relapse due to drug resistance. Recent studies show that bromodomains and extra-terminal (BET) protein inhibitors are promising anti-cancer agents. ARV-825, comprising a BET inhibitor conjugated with cereblon ligand, was recently developed to attenuate the growth of multiple tumors in vitro and in vivo. However, the functional and molecular mechanisms of ARV-825 in T-ALL remain unclear. This study aimed to investigate the therapeutic efficacy and potential mechanism of ARV-825 in T-ALL. Methods Expression of the BRD4 were determined in pediatric T-ALL samples and differential gene expression after ARV-825 treatment was explored by RNA-seq and quantitative reverse transcription-polymerase chain reaction. T-ALL cell viability was measured by CCK8 assay after ARV-825 administration. Cell cycle was analyzed by propidium iodide (PI) staining and apoptosis was assessed by Annexin V/PI staining. BRD4, BRD3 and BRD2 proteins were detected by western blot in cells treated with ARV-825. The effect of ARV-825 on T-ALL cells was analyzed in vivo. The functional and molecular pathways involved in ARV-825 treatment of T-ALL were verified by western blot and chromatin immunoprecipitation (ChIP). Results BRD4 expression was higher in pediatric T-ALL samples compared with T-cells from healthy donors. High BRD4 expression indicated a poor outcome. ARV-825 suppressed cell proliferation in vitro by arresting the cell cycle and inducing apoptosis, with elevated poly-ADP ribose polymerase and cleaved caspase 3. BRD4, BRD3, and BRD2 were degraded in line with reduced cereblon expression in T-ALL cells. ARV-825 had a lower IC50 in T-ALL cells compared with JQ1, dBET1 and OTX015. ARV-825 perturbed the H3K27Ac-Myc pathway and reduced c-Myc protein levels in T-ALL cells according to RNA-seq and ChIP. In the T-ALL xenograft model, ARV-825 significantly reduced tumor growth and led to the dysregulation of Ki67 and cleaved caspase 3. Moreover, ARV-825 inhibited cell proliferation by depleting BET and c-Myc proteins in vitro and in vivo. Conclusions BRD4 indicates a poor prognosis in T-ALL. The BRD4 degrader ARV-825 can effectively suppress the proliferation and promote apoptosis of T-ALL cells via BET protein depletion and c-Myc inhibition, thus providing a new strategy for the treatment of T-ALL.


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