miR-125b reverses cisplatin resistance by regulating autophagy via targeting RORA/BNIP3L axis in lung adenocarcinoma

The platinum-based chemotherapy is one of the most frequently used treatment protocols for lung adenocarcinoma(LUAD),and chemoresistance,however,usually results in treatment failure and limits its application in the clinic.It has been shown that microRNAs(miRNAs)play a significant role in tumor chemoresistance.In this study,miR-125b was identified as a specific cisplatin(DDP)-resistant gene in LUAD,as indicated by the bioinformatics analysis and the real-time quantitative PCR assay.The decreased serum level of miR-125b in LUAD patients was correlated with the poor treatment response rate and short survival time.MiR-125b decreased the A549/DDP proliferation,and the multiple drug resistance-and autophagy-related protein expression levels,which were all reversed by the inhibition of miR-125b.In addition,xenografts of human tumors in nude mice were suppressed by miR-125b,demonstrating that through autophagy regulation,miR-125b could reverse the DDP resistance in LUAD cells,both in vitro and in vivo.Further mechanistic studies indicated that miR-125b directly repressed the expression levels of RORA and its downstream BNIP3L,which in turn inhibited autophagy and reversed chemoresistance.Based on these findings,miR-125b in combination with DDP might be an effective treatment option to overcome DDP resistance in LUAD.

Research progress on lung cancer stem cells in epidermal growth factor receptor–tyrosine kinase inhibitor targeted therapy resistance in lung adenocarcinoma

Lung cancer is the leading cause of cancer-related deaths globally.In recent years,with the widespread use of genetic testing,epidermal growth factor receptor–tyrosine kinase inhibitor(EGFR-TKI)–targeted drugs have been efficacious to patients with lung adenocarcinoma exhibiting EGFR mutations.However,resistance to treatment is inevitable and eventually leads to tumor progression,recurrence,and reduction in the overall treatment efficacy.Lung cancer stem cells play a crucial role in the development of resistance toward EGFR-TKI–targeted therapy for lung adenocarcinoma.Lung cancer stem cells possess self-renewal,multilineage differentiation,and unlimited proliferation capabilities,which efficiently contribute to tumor formation and ultimately lead to tumor recurrence andmetastasis.In this study,we evaluated the origin,markers,stemness index,relevant classic studies,resistance mechanisms,related signaling pathways,and strategies for reversing lung cancer stem cell resistance to EGFR-TKIs to provide new insights on delaying or reducing resistance and to improve the treatment efficacy of patients with EGFR-mutated lung adenocarcinoma in the future.

Bevacizumab Combined with Icotinib Overcomes Osimertinib Resistance in a Patient of Non-Small Cell Lung Cancer

A 61-year-old Chinese woman was diagnosed as primary pulmonary adenocarcinoma of left superior lobe with epidermal growth factor receptor(EGFR)19 del mutation positive.Treatment with icotinib was given,but her disease progressed after 6 months remission.CT-guide needle biopsy for the new lesion in inferior lobe of left lung demonstrated intrapulmonary metastasis,and EGFR gene panel by Amplification Refractory Mutation System Polymerase Chain Reaction(ARMS-PCR)confirmed EGFR T790M mutation.Treatment with osimertinib was initiated.After 2 months remission,the disease progressed.Re-biopsy was performed for the tumor in the inferior lobe of left lung,and ARMS-PCR demonstrated no other gene mutation except EGFR 19 del.Icotinib was re-challenged,but disease progressed continuously.Bevacizumab was added,and partial response was achieved after 2-cycle of combination therapy.The non-small cell lung cancer(NSCLC)in this case maintained EGFR activating mutation and lost EGFR T790M mutation was a genetic change after osimertinib treatment.This case suggests the re-challenge of the first-generation EGFR-TKIs combined with bevacizumab may overcome the tumor resistance and prolong survival of NSCLC patient.

Expression of lung resistance protein in patients with gastric carcinoma and its clinical significance

INTRODUCTION The efficacy of chemotherapy in the treatment of cance patients is often hampered by the presence or appearance of multidrug resistance(MDR) of tumor cells.

Mechanism of Drug Resistance Identified in Human Lung Adenocarcinoma Cell Line SPC-A1 Selected for Resistance to Docetaxel

Objective： To investigate the mechanism of resistance to docetaxel in human lung cancer. Methods： Human lung carcinoma SPC-A1/Docetaxel cells were derived from parental SPC-A1 cells by continuous exposure to increasing concentration of docetaxel. The drug sensitivity was measured by MTT assay in vitro. The cDNA microarray identified a set of differentially expressed genes, and some genes were confirmed by RT-PCR. P-glycoprotein level was measured by flow cytometry analysis. Results： The results of drug sensitivity measured by MTT assay showed that SPC-A1/Docetaxel cells were 13.2-fold resistant to docetaxel and cross-resistant at varying levels to other drugs. The cDNA microarray results identified a set of differentially expressed genes, which showed 428 genes that were up-regulated and 506 genes that were down-regulated in SPC-A1/Docetaxel ceils, and some genes were confirmed by RT-PCR. Flow cytometry analysis suggests expression of P-glycoprotein （P-gp） was more abundant in SPC-A1/Docetaxel cells than in the parental cells and docetaxel selection reduces the apoptotic response. Conclusion： The results suggest that docetaxel selection led to changes in gene expression that contribute to the multidrug resistance phenotype.

Relationship between Methylation Status of Multi-drug Resistance Protein(MRP) and Multi-drug Resistance in Lung Cancer Cell Lines

Objective： To study the relationship between the methylation status of multi-drug resistance protein （MRP） gene and the expression of its mRNA and protein in lung cancer cell lines. Methods： Human embryo lung cell line WI-38, lung adenocarcinoma cell line SPCA-1 and its drug-resistant cells induced by different concentrations of doxorubicin were treated with restriction endonuclease Eco47III. The methylation status of MRP was examined by PCR, and the expressions of its mRNA and protein were evaluated by in situ hybridization and immunohistochemistry. Results： MRP gene promoter region of WI-38 cells was in hypermethylation status, but the promoter region of MRP in SPCA-1 cells and their resistant derivatives induced by different concentrations of doxorubicin were in hypomethylation status. There were significant differences in the expression of MRP mRNA among WI-38 cell line, SPCA-1 cells and their drug-resistant derivatives induced by different concentration of doxorubicin. Consistently, MRP immunostaining presented similar significant differences. Conclusion： The promoter region of MRP in SPCA-1 lung adenocarcinoma cells was in hypomethylation status. The hypomethylation status of 5＇ regulatory region of MRP promoter is an important structural basis that can increase the activity of transcription and results in the development of drug resistance in lung cancer.

Effects of PI3K Inhibitor NVP-BKM120 on Acquired Resistance to Gefitinib of Human Lung Adenocarcinoma H1975 Cells

The effects of class I PI3K inhibitor NVP-BKM120 on cell proliferation, cell cycle distri- bution, cellular apoptosis, phosphorylation of several proteins of the PI3K/AKT signaling pathway and the mRNA expression levels of HIFl-ct, VEGF and MMP9 in the acquired gefitinib resistant cell line H1975 were investigated, and whether NVP-BKM120 can overcome the acquired resistance caused by the EGFR T790M mutation and the underlying mechanism were explored. MTT assay was performed to detect the effect of gefitinib, NVP-BKM120, NVP-BKM120 plus 1 ~unol/L gefitinib on growth of H1975 cells. The distribution of cell cycle and apoptosis rate of H1975 cells were examined by using flow cytometry. The mRNA expression levels of tumor-related genes such as HIFI-a, VEGF and MMP9 were detected by using real-time quantitative PCR. Western blotting was used to detect the ex- pression level of phosphorylated proteins in the PI3K/AKT signaling pathway, such as Ser473-p-AKT, Ser235/236-p-S6 and Thr70-p-4E-BP1, as well as total AKT, $6 and 4E-BP1. The results showed that the NVP-BKM120 could inhibit the growth of H1975 cells in a concentration-dependent manner, and H1975 cells were more sensitive to NVP-BKM120 than gefitinib （IC50：1.385 vs. 15.09 ~mol/L respec- tively）, whereas combination of NVP-BKM120 and gefitinib （1 ~trnol/L） did not show more obvious ef- fect than NVP-BKM120 used alone on inhibition of cell growth （P〉0.05）. NVP-BKM120 （1 ~unol/L） increased the proportion ofH1975 cells in G0~G1 phase and the effect was concentration-dependent, and 2 ~maol/L NVP-BKM120 promoted apoptosis ofH1975 cells. There was no significant difference in the proportion of H1975 cells in G0-G1 phase and apoptosis rate between NVP-BKM120-treated alone group and NVP-BKM120 plus genfitinib （1 ~unol/L）-treated group or between DMSO-treated control group and gefitinib （1 Ixmol/L）-treated alone group （P〉0.05 for all）. It was also found that the mRNA expression levels of these genes were down-regulated by NVP-BKM120 （1 ~unol/L）, and NVP-BKM120 （1 ~tmol/L） or NVP-BKM120 （1 pmol/L） plus gefitinib （1 ~tmol/L） obviously inhibited the activation of Akt, $6 and 4E-BP1 as compared with control group, but single use of gefitinib （1 pmol/L） exerted no significant effect. These data suggested that NVP-BKM120 can overcome gefitinib resistance in H1975 cells, and the combination of NVP-BKM120 and gefitinib did not have additive or synergistic effects. It was also concluded that NVP-BKM120 could overcome the acquired resistance to gefitinib by down-regulating the phosphorylated protein in PI3K/AKT signal pathways in H1975 cells, but it could not enhance the sensitivity of H 1975 cells to gefitinib.

Molecular Mechanisms Contributing to Resistance to Tyrosine Kinase-Targeted Therapy for Non-Small Cell Lung Cancer

One of the most important pathways in non-small cell lung cancer(NSCLC) is the epidermal growth factor receptor(EGFR) pathway. This pathway affects several crucial processes in tumor development and progression,including tumor cell proliferation,apoptosis regulation,angiogenesis,and metastatic invasion.Targeting EGFR is currently being intensely explored.We are witnessing the development of a number of potential molecular-inhibiting treatments for application in clinical oncology.In the last decade,the tyrosine kinase(TK) domain of the EGFR was identified in NSCLC patients,and it has responded very well with a dramatic clinical improvement to TK inhibitors such are gefitinib and erlotinib.Unfortunately,there were primary and/or secondary resistance to these treatments,as shown by clinical trials.Subsequent molecular biology studies provided some explanations for the drug resistance phenomenon.The molecular mechanisms of resistance need to be clarified.An in-depth understanding of these targeted-therapy resistance may help us explore new strategies for overcoming or reversing the resistance to these inhibitors for the future of NSCLC treatment.

Management of tyrosine kinase inhibitor resistance in lung cancer with EGFR mutation

The identification of driver mutations and drugs that inhibit their activity has been a major therapeutic advance for patients with advanced lung adenocarcinoma. Unfortunately, the success of these drugs is limited by the universal development of resistance. Treatment failure can result from inadequate drug exposure or selection of resistant malignant clones. Clinically distinct mechanisms of disease progression have been identified and can inform treatment decisions. Investigations into the biochemical mechanisms of tyrosine kinase inhibitor resistance may provide additional therapeutic targets by which the efficacy of targeted therapy can be improved.

THE CORRELATION BETWEEN THE EXPRESSION OF MULTIDRUG RESISTANCE RELATED GENE AND CELL APOPTOSIS AND CLINICAL SIGNIFICANCE IN NON-SMALL CELL LUNG CANCER

Objective: To explore the correlation and clinical significance between expression of MDR (multidrug resistance) related gene MRP, MDR1, C-erbB-2 and cell apoptosis in non-small cell lung cancer (NSCLC). Methods: RT-PCR, Immunohistochemistry were used to examine the expression of mRNA and protein in the MDR and apoptosis related gene. Apoptosis cells were assayed by Terminal deoxynucleotidyl transferase (TdT)- mediated biotin dUTP nick end-labeling (TUNEL). Results: The positive rates of MRP, MDR1, C-erbB-2, bc1-2, C-myc mRNA in 63 cases NSCLC were 81.0% (51/63), 38.1%(24/63), 47.6%(30/63), 65.1%(41/63), 76.2%(48/63) respectively. Their levels were higher than those of corresponding proteins (74.6%, 34.9%, 46.0%, 61.9%, 71.4%, respectively). The significant association was found between the mRNA level and the protein expression (r =+0.764, P<0.02). The C-myc expression in 2 cases adjacent and benign lung tissue were light positive, and another 3 cases were negative. The positive correlation were demonstrated between C-myc and C-erbB-2 (r=+0.547, p=0.001) as well as bcl-2 and C-erbB-2 (r =+0.486, p=0.023) in NSCLC. There is no any correlation among bcl-2, C-myc and MRP or MDR1. There exists inverse correlation between apoptotic index and bcl-2 (r = -0.587, p = 0.017), and no any correlation among apoptotic index and MRP or MDR1 or C-erbB-2 or C-myc. The average apoptotic index were higher in the effective chemotherapy group (27.2( 2.1, 30.5(1.8) than that in the non-effective chemotherapy group (9.4( 1.3, 12.6( 2.4) with adenocarcinoma and squamous cell carcinoma (p =0.01, p=0.004). The positive rates of bcl-2, MRP, C-erbB-2 expression in the effective chemotherapy group (31.8%, 40.9%, 22.7%, respectively) were lower than those in the non-effective chemotherapy group (77.4%, 90.3%, 67.7%, respectively) (p=0.036, p=0.012, p=0.01), but MDR1 and C-myc expression have no any significant difference (p=0.067, p=0.282). The median survival time in the patients with coexpression of more than three MDR and/or apoptosis related genes are shorter (8.6 months) than that in those patients with coexpression of less than three MDR and/or apoptosis related genes (15.5 months)(p=0.01). Conclusion: The multidrug resistance in NSCLC is not only related to many drug resistance genes, but also involved in cell apoptosis and apoptosis related gene expression. The coexpression of MDR and apoptosis related gene is related to the survival time.

Role of MetallothioneinlH in Cisplatin Resistance of Non-Small Cell Lung Cancer Cells

Objective： Despite platinum-based adjuvant chemotherapy has improved greatly patients＇ outcomes, drug resistance poses a major impediment to the successful use of such an effective agent. Metallothioneins（MTs） are known to play putative roles in cancer cell proliferation, apoptosis, differentiation, drug resistance and prognosis. The present studiy was to investigte the role of metallethioeinlH（MTIH） in cisplatin resistance of human non-small cell lung cancer（NSCLC） cell lines in vitro or its possible molecular mechanisms. Methods： MTIH mRNA expression in A549 and A549/DDP cells was detected by RT-PCR. A recombinant eukaryotic expression plasmid pcDNA3.1（-）-MT1H was constructed and transfected into A549 cells which express no MTIH. MT1H siRNA was transfected into A549/DDP cells which express MTIH highly. MTIH expression was detected by RT-PCR and Immunoblot. The chemosensitivity to cisplatin was assessed by MTT assay. Apoptosis rate was determined by Tunel and FCM. Bcl-2 and Bax were determined by immunohistochemistry. Results： MT1H mRNA was expressed in A549/DDP but not in A549. After transfection of MT1H, MT1H expression was enhanced and the chemosensitivity to cisplatin was decreased in A549 cells. Inversely, after transfection of MT1H siRNA, MT1H expression was decreased and the chemosensitivity to cisplatin was increased in A549/DDP. The apoptosis rate induced by cisplatin was increased and Bcl-2 was down-regulated but Bax showed little change in A549/DDP cells interferred with MT1H siRNA. Conclusion： MT1H overexpression can promote drug resistance in A549 cells . Down-regulation of MTIH interfered with siRNA can effectively reverses the drug resistance in A549/DDP cells by down-regulating the expression of Bcl-2 and increasing cisplatin induced apoptosis. SiRNA targeting MT1H combined with chemotherapy may be a very promising strategy for treatment of lung cancer.

Differential expression of breast cancer-resistance protein,lung resistance protein,and multidrug resistance protein 1 in retinas of streptozotocin-induced diabetic mice

AIM：To investigate the altering expression profiles of efflux transporters such as breast cancer-resistance protein（BCRP）,lung resistance protein（LRP）,and multidrug resistance protein 1（MDR1） at the inner blood-retinal barrier（BRB） during the development of early diabetic retinopathy（DR） and/or aging in mice.METHODS：Relative m RNA and protein expression profiles of these three efflux transporters in the retina during the development of early DR and/or aging in mice were examined.The differing expression profiles of Zonula occludens 1（ ZO-1） and vascular endothelial growth factor-A（ VEGFA） in the retina as well as the perfusion characterization of fluorescein isothiocyanate（FITC）-dextran and Evans blue were examined to evaluate the integrity of the inner BRB.RESULTS：There were significant alterations in these three efflux transporters＇ expression profiles in the m RNA and protein levels of the retina during the development of diabetes mellitus and/or aging.The development of early DR was confirmed by the expression profiles of ZO-1 and VEGFA in the retina as well as the compromised integrity of the inner BRB.CONCLUSION：The expression profiles of some efflux transporters such as BCRP,LRP,and MDR1 in mice retina during diabetic and/or aging conditions are tested,and the attenuated expression of BCRP,LRP,and MDR1 along with the breakdown of the inner BRB is found,which may be linked to the pathogenesis of early DR.

Expression and Prognostic Significance of Multidrug Resistance Associated Protein (MRP) Gene in Non-small Cell Lung Cancer by in Site Hybridization

Objective: To study on the effect of MRP gene overexpression on prognosis of patients with non-small lung cancer (NSCLC). Methods: Paraffin-embedded tissues from 47 cases of NSCLC who had undergone radical tumor resection were examined for expression of MRP gene mRNA by in situ hybridization using labelled digoxigenin probes combined with immunohistochemistry. All the patients were retrospectively followed-up. Results: All of the 47 lung cancer specimens were found to have overexpression of MRP gene mRNA. It was significantly correlated with patients' survival time, response to chemotherapy, recurrence or metastases after surgery, but was not correlated with histology, tumor size, node status, TNM stage, degree of differentiation, age and sex. Conclusion: Overexpression of MRP gene is a marker of prognostic significance in patients with NSCLC.

A multicenter randomized, double-blind, placebo-controlled trial to evaluate the safety and efficacy of rhubarb in treating acute exacerbation of chronic obstructive pulmonary disease of the syndrome type phlegm-heat obstructing the lungs

Objective:To observe the clinical efficacy and safety of oral administration of the traditional Chinese herb rhubarb to treat acute exacerbation of chronic obstructive pulmonary disease(AECOPD).Method:This was a multicenter randomized double-blinded placebo controlled study that took place in 7 provinces of China that enrolled 244 patients(aged 18e80 years)who had acute exacerbation of COPD with the traditional Chinese syndrome pattern of phlegm-heat obstructing lung.Participants were divided into experimental and control groups.The experimental group received 4.5 g of rhubarb granules twice daily and the control group received placebo granules.Both groups also received conventional Western therapy consisting of oxygen therapy,an antibiotic,expectorant,and a bronchodilator.Treatment lasted 10 days.Symptom scores for cough,sputum volume and color,wheezing and chest tightness before treatment and on days 3,5,7,and 10 during the treatment were recorded.Lung function,arterial blood gas and levels of serum inflammatory factors,interleukin-4(IL-4),interleukin-8(IL-8),and interleukin-10(IL-10)and tumor necrosis factor-alpha(TNF-a),before and after treatment were measured.Results:The sample size of the full analysis set(FAS)was 244 participants,and the sample size of per protocol set(PPS)was 235.Following 10 days’treatment,symptom scores of the experimental group were markedly lower than those of the placebo group(FAS:mean difference
1.67,95%CI:e2.66 to
0.69,P Z 0.001;PPS:mean difference
1.55,95%CI:
2.56 to
0.54,P Z 0.003).Lung function in the experimental group was significantly higher than in the placebo group(FEV1,FAS:mean difference 0.12,95%CI:0.06 to 0.18;P<0.001;PPS:mean difference 0.12,95%CI 0.05 to 0.18;P<0.001.FVC:FAS:mean difference 0.16,95%CI:0.06 to 0.26;P Z 0.002;PPS:mean difference 0.16,95%CI 0.05 to 0.26;P Z 0.003.FEV1%,FAS:mean difference 5.95,95%CI:3.36 to 8.53;P<0.001;PPS:mean difference 5.92,95%CI 3.28 to 8.56;P<0.001.).PaO2,PaCO2,as well as serum inflammatory factors were also improved when compared to the placebo group.There were no significant differences in the incidence rate of adverse reaction between the two groups.Conclusions:Compared with placebo,rhubarb granules significantly reduced symptom scores,improved blood oxygen level,controlled systemic inflammatory response,without significant adverse effects.Thus,rhubarb may be a beneficial adjuvant method for treating the phlegm-heat obstructing the lung syndrome pattern of AECOPD.

Advances in the management of acquired resistance to EGFR-TKI in non-small cell lung cancer

Drugs that specifically target the tyrosine kinase domain of epidermal growth factor receptor(EGFR), such as erlotinib or gefitinib, have exhibited striking efficacy in non-small cell lung cancer(NSCLC) patients harboring activating EGFR mutations. However, acquired resistance inevitably develops and remains a serious barrier for the successful management of patients with this disease. Multiple mechanisms are reportedly involved in the process of acquired resistance, which provide new insights into the management of EGFRtyrosine kinase inhibitor(EGFR-TKI) resistance. Here, we provide an overview of the emerging treatment approaches for patients with EGFR-TKI resistance.

The expression and significance of the multidrug resistance-related proteins P-gp, MRP and LRP in human non-small cell lung cancer tissues

Objective: To explore the expression and significance of the multidrug resistance-related proteins P-glycopro-tein (P-gp), multidrug resistance-related protein (MRP), lung resistance protein (LRP) in human non-small cell lung cancer (NSCLC) tissues and paratumor tissues. Methods: Immunohistochemistry (IHC) was used to examine the expression level of proteins P-gp, MRP and LRP in 43 samples of NSCLC and 15 samples of paratumor tissues. Results: The expression rates of P-gp, MRP and LRP in 43 tumor tissues were 74.42% (32/43), 67.44% (29/43) and 88.37% (38/43), respectively, while in 15 paratumor tissues were 13.33% (2/15), 20.00% (3/15) and 6.67% (1/15), respectively. There was significant difference in the expression of proteins (P-gp, MRP and LRP) between lung cancer tissues and paratumor tissues (P < 0.05). The expres-sion of proteins P-gp, LRP in lung adenocarcinoma were higher than that in other pathological carcinomas (P < 0.05). The expression of protein MRP was not related to pathological type, clinical stage and classification of histodifferentiation (P > 0.05). Conclusion: Multidrug resistance is more common in NSCLC. The proteins of P-gp, MRP and LRP participated in the formation of multidrug resistance in lung cancer. Detection of multidrug resistance-related proteins in lung cancer tissues may be useful to choice drugs.

miR-124 Modulates Gefitinib Resistance through SNAI2 and STAT3 in Non-small Cell Lung Cancer

Gefitinib is used as a first-line treatment for advanced non-small cell lung cancer（NSCLC）.Unfortunately,most NSCLC patients inevitably develop gefitinib resistance during treatment.In addition to EGFR mutation status,the mechanisms involved are largely unknown.In this study,we showed that mi R-124,a tumor suppressor,was significantly down-regulated in gefitinib-resistant NSCLC patients and cell lines compared with gefitinib-sensitive patients and cell lines.In addition,the mi R-124 depletion induced gefitinib resistance,and mi R-124 overexpression sensitized gefitinib-resistant cells to gefitinib.Mechanistic analysis revealed that mi R-124 decreased SNAI2 and STAT3 expression by directly targeting their 3＇UTRs and that knocking down SNAI2 or STAT3 partly reversed the gefitinib resistance induced by mi R-124 depletion.Our data demonstrate that the mi R-124 plays a new critical role in acquired resistance to gefitinib and that the manipulation of mi R-124 might provide a therapeutic strategy for reversing acquired gefitinib resistance.

Specific growth inhibition by alteration of metabolic pathway using Chinese herbal medicine in tyrosine kinase inhibitor resistant non-small cell lung cancer

OBJECTIVE Lung cancer is the leading cause of cancer death worldwide.Epidermal growth factor receptor(EGFR)mutation(s)is/are common in non-small cell lung cancer(NSCLC)in Asian population,resulting in lung tumor formation.L858 Rsubstitution mutation on exon 21 and in-flame deletion mutation on exon 19 are the two most common forms of EGFR mutation.Molecular targeted therapy using tyrosine kinase inhibitor(TKI)targeting EGFR shows promising initial response,however drug resistance is common.Therefore,it is needed to identify new inhibitors to tackle TKI-resistance.In this study,we aim to investigate the effect of multiple single purified compounds derived from Chinese herbal medicines(CMHs)on a panel of NSCLC cell lines with different EGFR mutational statuses and TKI sensitivity.We also examine the biological functional effect and drug action mechanism of these cell lines after drug treatment.METHODS We have reviewed the literature and selected ten single purified compounds derived from CMHs which exhibited the highest potential of cancer suppression effect in NSCLC.We have recruited three EGFR-dependent NSCLC cell lines for drug screening using cytotoxicity assay.A549 is used as EGFR wild-type control.Two TKI-resistant NSCLC cell lines were used,H1975 harbors double mutation(EGFRL858R+T790M)and H1650 harbors EGFRexon 19 deletion.H2228is a NSCLC cell line which harbours EML4-ALK fusion gene and was used as EGFR-independent cell line control.MTT assay was used to determine the drug efficacy and IC50 value.Then functional assays including cell cycle arrest analysis and apoptosis assay was used to determine the biological effect after drug treatment.RESULTS MTT assay revealed that six out of ten candidate agents showed significant cancer-inhibiting effects in H1650 and H1975cells.Three compounds exhibited IC50 value at micro-molar levels while another three compounds exhibited IC50 at as low as nano-molar levels.One compound exhibited specificity on EGFR-dependent NSCLC cell lines,which showed 10-fold more selective than the EGFR-independent H2228 cells.Cell cycle analysis and immunoblotting assay showed that one effective compound,designated was MUST-1,altered the metabolic pathway of glucose metabolism and lipid metabolism,and induced cell cycle arrest at G1 phase in NSCLC with EGFR mutation.However,the anti-proliferative effects were distinct in NSCLC cell lines with different EGFR mutation patterns.CONCLUSION MUST-1 significantly induced cell cycle arrest in four NSCLC in EGFR mutant cell lines but the inhibiting effect was not significant in EGFR wildtype cell line.Immunobloting assay revealed that overall intracellular lipid content,glycolytic enzymes PKM2 and cell cycle regulatory gene expression were altered after 72 hcompound treatment in the responsive cells.Further investigation is required to elucidate the underlying reason of drug selectivity and the role of glucose and lipid metabolism in regulating drug sensitivity.

Bioinformatics Identification of ZNFs/LINC00520/miR-181d/BCL2 Axis as a Novel Network in Cisplatin-Resistant Lung Adenocarcinoma Cells

Background: Resistance to cisplatin (DDP) leads to poor prognosis in patients with Lung Adenocarcinoma (LUAD) and limits its clinical application. It has been confirmed that autophagy promotes chemoresistance and, therefore, novel strategies to reverse chemoresistance by regulating autophagy are desperately needed. Methods: The differentially expressed lncRNAs (DElncRNAs), miRNAs (DEmiRNAs), and mRNAs (DEmRNAs) between A549 and A549/DDP cell lines were identified using the limma package in R, after gene expression profiles were obtained from Gene Expression Omnibus (GEO) database. By combining Autophagy-Related Genes (ARGs) from Human Autophagy Database (HADb), the interactions lncRNA-miRNAs and the interactions miRNAs-mRNAs respectively predicted by miRcode and miRDB/Targetscan database, the autophagy-related ceRNA network was constructed. Then, extraction of ceRNA subnetwork and Cox regression analyses were performed. A prognosis-related ceRNA subnetwork was constructed, and the upstream Transcription Factors (TFs) regulating lncRNAs were predicted by the JASPAR database. Finally, the expression patterns of candidate genes were further verified by quantitative real-time polymerase chain reaction (qRT-PCR) experiments. Results: A total of 3179 DEmRNAs, 180 DEmiRNAs, and 160 DElncRNAs were identified, and 35 DEmRNAs were contained in the HADb. Based on the ceRNA hypothesis, we established a ceRNA network, including 10 autophagy-related DEmRNAs, 9 DEmiRNAs, and 14 DElncRNAs. Then, LINC00520, miR-181d, and BCL2 were identified to construct a risk score model, which was confirmed to be a well-predicting prognostic factor. Furthermore, 5 TF ZNF family members were predicted to regulate LINC00520, whereas the RT-PCR results showed that the 5 ZNFs were consistent with the bioinformatics analysis. Finally, a ZNF regulatory LINC00520/miR-181d/BCL2 ceRNA subnetwork was constructed. Conclusions: An ZNFs/LINC00520/miR-181d/BCL2 axis as a novel network in DDP-resistant LUAD has been constructed successfully, which may provide potential therapeutic targets for LUAD.

The synergistic effects of PRDX5 and Nrf2 on lung cancer progression and drug resistance under oxidative stress in the zebrafish models

Previous studies have shown that PRDX5 and Nrf2 are antioxidant proteins related to abnormal reactive oxidative species(ROS).PRDX5 and Nrf2 play a critical role in the progression of inflammations and tumors.The combination of PRDX5 and Nrf2 was examined by Co-immunoprecipitation,western blotting and Immunohistochemistry.H2O2 was applied to affect the production of ROS and induced multi-resistant protein 1(MRP1)expression in NSCLC cells.The zebrafish models mainly investigated the synergistic effects of PRDX5 and Nrf2 on lung cancer drug resistance under oxidative stress.We showed that PRDX5 and Nrf2 form a complex and significantly increase the NSCLC tissues compared to adjacent tissues.The oxidative stress improved the combination of PRDX5 and Nrf2.We demonstrated that the synergy between PRDX5 and Nrf2 is positively related to the proliferation and drug resistance of NSCLC cells in the zebrafish models.In conclusion,our data indicated that PRDX5 could bind to Nrf2 and has a synergistic effect with Nrf2.Meanwhile,in the zebrafish models,PRDX5 and Nrf2 have significant regulatory impacts on lung cancer progression and drug resistance activities under oxidative stress.