Cigarette Smoke Induces Gefitinib Resistance in NSCLC Cells via ROS/Sirt3/SOD2 Pathway / 中国肺癌杂志

BACKGROUND@#Epidermal growth factor receptor (EGFR) gene mutations are the most common driver mutations in non-small cell lung cancer (NSCLC). To prolong the survival of the patients, EGFR tyrosine kinase inhibitors (TKIs) resistance in NSCLC is a major challenge that needs to be addressed urgently, and this study focuses on investigating the mechanism of cigarette smoke (CS) induced Gefitinib resistance in NSCLC.@*METHODS@#PC-9 and A549 cells were cultured in vitro and treated with 1 µmol/L Gefitinib for 4 h and 10% cigarette smoke extract (CSE) for 48 h. Western blot was used to detect Sirtuin 3 (Sirt3) and superoxide dismutase 2 (SOD2) protein expressions; DCFH-DA probe was used to detect intracellular reactive oxygen species (ROS); CCK-8 kit was used to detect cell activity, and EdU was used to detect cell proliferation ability. Sirt3 overexpression plasmid (OV-Sirt3) was transfected in PC-9 and A549 cells and treated with 1 µmol/L Gefitinib for 4 h and 10% CSE for 48 h after N-acetylcysteine (NAC) action. The expressions of Sirt3 and SOD2 were detected by Western blot; the ROS level in the cells was detected by DCFH-DA probe, and the cell activity was detected by CCK-8.@*RESULTS@#CSE induced an increase in the 50% inhibitory concentration (IC50) of both PC-9 and A549 cells to Gefitinib (P<0.01) and enhanced the proliferation of PC-9 and A549 cells, suggesting that CS induced Gefitinib resistance in NSCLC. ROS was involved in CSE-induced Gefitinib resistance (P<0.05). CSE induced low expressions of Sirt3 and SOD2 (P<0.01), and Sirt3/SOD2 was associated with poor prognosis in lung cancer patients (P<0.05). OV-Sirt3 in PC-9 and A549 cells reversed CSE-induced Gefitinib resistance (P<0.05) and significantly reduced ROS production. NAC reversed CSE-induced Gefitinib resistance in PC-9 and A549 cells (P<0.05).@*CONCLUSIONS@#The ROS/Sirt3/SOD2 pathway is involved in CS-induced Gefitinib resistance in NSCLC.

Effect of SLC7A11 gene downregulation on the gefitinib resistance of lung adenocarcinoma PC9/GR cells and its mechanism / 中华肿瘤杂志

Objective: To screen the key genes involved in gefitinib resistance of lung adenocarcinoma PC9/GR cells which harbored 19 exon mutation of epidermal growth factor receptor (EGFR) gene, and discuss the effect and mechanism of downregulation of solute carrier family 7 member 11 (SLC7A11) on the gefitinib resistance of PC9/GR cells. Methods: RNA microarray was conducted to detect the gene expressions in PC9 and PC9/GR cells. The differently expressed genes were screened by using limma package of R language and analyzed by Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis. Western blotting was performed to determine the expression of SLC7A11 protein in PC9 and PC9/GR cells. PC9/GR cells were infected with lentivirus plasmid containing short hairpin RNA (shRNA) targeting SLC7A11 or negative control shRNA (sh-NC), respectively. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed to evaluate the efficacy of shRNA on the expression of SLC7A11 mRNA. Cell counting kit-8 (CCK-8) assay was conducted to determine the suppressing effect of gefitinib on PC9/GR cells. Mito-Tracker Red CMXRos probe and malondialdehyde (MDA) assay kit were used to evaluate gefitinib-induced ferroptosis in PC9/GR cells. Immunohistochemistry (IHC) was conducted to detect the expression of SLC7A11 protein in the tumor tissues of advanced stage lung adenocarcinoma patients harboring 19 exon mutation of EGFR gene. Thirty-six advanced stage lung adenocarcinoma patients who received EGFR-tyrosihe kinase inhibitor(TKI) as first-line treatment in Fourth Hospital of Hebei Medical Unviersity were enrolled. Kaplan-Meier survival curve was drawn to analyze the correlation between SLC7A11 expression and progression-free survival (PFS) of the patients. Results: RNA array demonstrated that 2 888 genes were differently expressed between PC9 and PC9/GR cells. KEGG analysis showed that ferroptosis-related gene was one of the most enriched region of the differently expressed genes between PC9 and PC9/GR cells. These ferroptosis-related gene cohort contained 13 genes, among which SLC7A11 exhibited the most significant difference. Western blotting showed that the expression of SLC7A11 protein in PC9/GR cells was significantly higher than that in PC9 cells (0.76±0.03 vs. 0.19±0.02, P<0.001). The 50% inhibiting concentration (IC(50)) of gefitinib was 35.08 μmol/L and 64.01 μmol/L for sh-SLC7A11 and sh-NC group PC9/GR cells, respectively. PC9/GR cells in sh-SLC7A11 group exhibited significantly lower density of mitochondria fluorescence after gefitinib treatment, compared to the sh-NC group (213.77±26.50 vs. 47.88±4.55, P<0.001). In addition, PC9/GR cells in sh-SLC7A11 group exhibited significantly higher MDA after gefitinib treatment, compared to the sh-NC group [(15.43±1.60) μmol/mg vs. (82.18±7.77) μmol/mg, P<0.001]. The PFS of the patients with low expression of SLC7A11 (n=18) was significantly longer than the patients with high expression of SLC7A11 (n=18, 16.77 months vs. 9.14 months, P<0.001). Conclusion: Downregulation of SLC7A11 could increase the sensitivity of PC9/GR cells to gefitinib by promoting ferroptosis.

Effect of SLC7A11 gene downregulation on the gefitinib resistance of lung adenocarcinoma PC9/GR cells and its mechanism / 中华肿瘤杂志

Objective: To screen the key genes involved in gefitinib resistance of lung adenocarcinoma PC9/GR cells which harbored 19 exon mutation of epidermal growth factor receptor (EGFR) gene, and discuss the effect and mechanism of downregulation of solute carrier family 7 member 11 (SLC7A11) on the gefitinib resistance of PC9/GR cells. Methods: RNA microarray was conducted to detect the gene expressions in PC9 and PC9/GR cells. The differently expressed genes were screened by using limma package of R language and analyzed by Kyoto encyclopedia of genes and genomes (KEGG) pathway enrichment analysis. Western blotting was performed to determine the expression of SLC7A11 protein in PC9 and PC9/GR cells. PC9/GR cells were infected with lentivirus plasmid containing short hairpin RNA (shRNA) targeting SLC7A11 or negative control shRNA (sh-NC), respectively. Real-time quantitative polymerase chain reaction (RT-qPCR) was performed to evaluate the efficacy of shRNA on the expression of SLC7A11 mRNA. Cell counting kit-8 (CCK-8) assay was conducted to determine the suppressing effect of gefitinib on PC9/GR cells. Mito-Tracker Red CMXRos probe and malondialdehyde (MDA) assay kit were used to evaluate gefitinib-induced ferroptosis in PC9/GR cells. Immunohistochemistry (IHC) was conducted to detect the expression of SLC7A11 protein in the tumor tissues of advanced stage lung adenocarcinoma patients harboring 19 exon mutation of EGFR gene. Thirty-six advanced stage lung adenocarcinoma patients who received EGFR-tyrosihe kinase inhibitor(TKI) as first-line treatment in Fourth Hospital of Hebei Medical Unviersity were enrolled. Kaplan-Meier survival curve was drawn to analyze the correlation between SLC7A11 expression and progression-free survival (PFS) of the patients. Results: RNA array demonstrated that 2 888 genes were differently expressed between PC9 and PC9/GR cells. KEGG analysis showed that ferroptosis-related gene was one of the most enriched region of the differently expressed genes between PC9 and PC9/GR cells. These ferroptosis-related gene cohort contained 13 genes, among which SLC7A11 exhibited the most significant difference. Western blotting showed that the expression of SLC7A11 protein in PC9/GR cells was significantly higher than that in PC9 cells (0.76±0.03 vs. 0.19±0.02, P<0.001). The 50% inhibiting concentration (IC(50)) of gefitinib was 35.08 μmol/L and 64.01 μmol/L for sh-SLC7A11 and sh-NC group PC9/GR cells, respectively. PC9/GR cells in sh-SLC7A11 group exhibited significantly lower density of mitochondria fluorescence after gefitinib treatment, compared to the sh-NC group (213.77±26.50 vs. 47.88±4.55, P<0.001). In addition, PC9/GR cells in sh-SLC7A11 group exhibited significantly higher MDA after gefitinib treatment, compared to the sh-NC group [(15.43±1.60) μmol/mg vs. (82.18±7.77) μmol/mg, P<0.001]. The PFS of the patients with low expression of SLC7A11 (n=18) was significantly longer than the patients with high expression of SLC7A11 (n=18, 16.77 months vs. 9.14 months, P<0.001). Conclusion: Downregulation of SLC7A11 could increase the sensitivity of PC9/GR cells to gefitinib by promoting ferroptosis.

Osimertinibe comparado a Erlotinibe Gefitinibe ou quimioterapia para tratamento de carcinoma pulmonar de células não pequenas com mutação do gene do receptor do fator de crescimento epidérmico (EFGR): revisão rápida / Osimertinib compared to erlotinib, gefitinib or chemotherapy for the treatment of non-small cell pumonary carcinoma with epidermal growth factor receptor (EFGR) gene mutation: rapid review

Mesilato de osimertinibe, gefitinibe, erlotinibe, quimioterapia padrão. Indicação: Câncer de pulmão de células não pequenas com mutação do receptor do fator de crescimento epidérmico (EGFR). Pergunta: Mesilato de osimertinibe é mais eficaz e seguro que gefitinibe, erlotinibe ou quimioterapia para os desfechos de sobrevida global, sobrevida livre de progressão e de segurança no tratamento de carcinoma pulmonar de células não pequenas com mutação do EGFR? Métodos: Levantamento bibliográfico foi realizado na base de dados PUBMED e EPISTEMONIKOS, seguindo estratégias de buscas predefinidas. Foi feita avaliação da qualidade metodológica das revisões sistemáticas com a ferramenta AMSTAR-2 (Assessing the Methodological Quality of Systematic Reviews Version 2). Resultados: Foram selecionadas duas revisões sistemáticas que atenderam aos critérios de elegibilidade. Conclusão: Mesilato de osimertinibe é mais eficaz do que gefitinibe ou erlotinibe na melhora da sobrevida global e da sobrevida livre de progressão em pacientes virgens de tratamento. Em pacientes previamente tratados, o mesilato de osimertinibe não é superior à quimioterapia padrão à base de platina no prolongamento da sobrevida global, mas é mais eficaz no aumento da sobrevida livre de progressão. Para câncer avançado, mesilato de osimertinibe não é mais eficaz do que a quimioterapia com ou sem pemetrexede para prolongar a sobrevida global, mas é mais eficaz em melhorar a sobrevida livre de progressão. Gefitinibe combinado com quimioterapia à base de pemetrexede foi superior à quimioterapia com ou sem pemetrexede na melhora da sobrevida global e da sobrevida livre de progressão

Osimertinib mesylate, gefitinib, erlotinib, standard chemotherapy. Indication: Non-small cell lung cancer with epidermal growth factor receptor (EGFR) mutation. Question: Is osimertinib mesylate more effective and safer than gefitinib, erlotinib or chemotherapy for overall survival, progression-free survival and safety outcomes in the treatment of non-small cell lung cancer with EGFR mutation? Methods: A bibliographic search was done in the PUBMED and EPISTEMONIKOS database, following predefined search strategies. The methodological quality of systematic reviews was evaluated using the Assessing the Methodological Quality of Systematic Reviews Version 2 tool. Results: Two systematic reviews were selected because they met the eligibility criteria. Conclusion: Osimertinib mesylate is more effective than gefitinib or erlotinib in improving overall survival and progression-free survival in treatment-naive patients. In previously treated patients, osimertinib mesylate is not superior to standard platinum-based chemotherapy in prolonging overall survival, but it is more effective in increasing progression-free survival. For advanced cancer, osimertinib mesylate is not more effective than chemotherapy with or without pemetrexed in prolonging overall survival, but it is more effective in improving progression-free survival. Gefitinib combined with pemetrexed-based chemotherapy was superior to chemotherapy with or without pemetrexed in improving overall survival and progression-free survival

Tratamientos de primera línea para pacientes estadio IV con adenocarcinoma pulmonar de mutación EGFR / First-line treatments for stage IV patients with EGFR-mutated lung adenocarcinoma

Lung cancer is one of the leading causes of death in the world. Current treatments act directly on the signal transduction pathways in cancer cells, mainly. One of the main pathways is associated with the Epidermal Growth Factor (EGFR), whose mutations leads to uncontrolled cell proliferation and a higher rate of cell invasion. Activating mutations in the EGFR gene, which includes deletions in exon 19 and the L858R mutation in exon 21, were detected in most patients with non-small cell lung cancer (NSCLC). Studies of EGFR tyrosine kinase inhibitors (EGFR-TKIs) such as Gefitinib, Erlotinib and Afatinib, compared with platinum-based treatments, showed that EGFR-TKIs produce increased disease-free survival, although only in patients whose cancers harbor activating mutations in the EGFR gene. Clinical trials also demonstrated that EGFR-TKIs are effective as first-line therapies in stage IV pulmonary adenocarcinoma. Here, the main aspects of the activation of the EGFR pathway in NSCLC will be reviewed, highlighting the importance for health professionals of correctly identifying activating mutations in the EGFR gene and acting quickly at the molecular level based on aforementioned treatments. (AU)

Gefitinib inhibits glycolysis and induces programmed cell death in non-small cell lung cancer cells / 南方医科大学学报

OBJECTIVE@#To observe the cell death pattern induced by gefitinib in non-small cell lung cancer A549 and H1975 cells and explore the possible mechanism in light of glycolysis.@*METHODS@#The inhibitory effects of gefitinib at 20, 30, or 40 μmol/L in A549 cells and at 20, 40, or 80 μmol/L in H1975 cells were examined using MTT assay. The changes of lactic acid level in the cells were determined with a lactic acid kit, and the expression levels of glycolysis-related proteins (PKM2 and HK2) and the proteins in PI3K-Akt-mTOR signaling pathway were detected using Western blotting. 2-NBDG was used for detecting glucose uptake capacity of the cells, and ATP kit was used to detect the intracellular ATP level. The mitochondrial membrane potential of the cells was examined with the JC-1 kit, and cell apoptosis was analyzed with Annexin V-FITC/PI double staining. The relative expression levels of the apoptotic proteins Bax and Bcl-2 and the autophagy marker protein LC3B were detected with Western blotting.@*RESULTS@#MTT assay showed that gefitinib inhibited the proliferation of A549 and H1975 cells in a time- and dose-dependent manner ( < 0.05). The IC of gefitinib at 24, 48 and 72 h was 48.6, 28.6 and 19.7 μmol/L in A549 cells and was 321.6, 49.1 and 14.6 μmol/L in H1975 cells, respectively. Gefitinib significantly lowered intracellular lactic acid level of the cells ( < 0.05) and down-regulated the expressions of PKM2 and HK2 proteins ( < 0.05) and PI3K-Akt-mTOR signaling pathway-associated proteins ( < 0.05). Gefitinib obviously inhibited glucose uptake and ATP levels in both A549 and H1975 cells ( < 0.05). Treatment with gefitinib induced obviously enhanced apoptosis in the cells, resulting in apoptosis rates of (10.77± 1.0)%, (14.5±0.4)%, (17.4±0.2)% and (32.1±0.6)% at 0, 20, 30 and 40 μmol/L in A549 cells ( < 0.05) and of (10.5±0.6)%, (13.2± 0.92)%, (18.9±0.98)% and (35.1±1.4)% at 0, 20, 40 and 80 μmol/L in H1975 cells, respectively ( < 0.05). The protein expression of Bax increased and that of Bcl-2 decreased following gefitinib treatment in the cells ( < 0.05). Gefitinib significantly increased autophagy in A549 and H1975 cells as shown by increased LC3B expressions following the treatment ( < 0.05).@*CONCLUSIONS@#Gefitinib can inhibit the proliferation, induce apoptosis and increase autophagy in A549 and H1975 cells. Gefitinib induces apoptosis of the cells possibly by affecting glycolysis and PI3K-Akt-mTOR signaling pathway.

Astemizole, an inhibitor of ether-à-go-go-1 potassium channel, increases the activity of the tyrosine kinase inhibitor gefitinib in breast cancer cells

Abstract Background Expression and activity of the potassium channel ether-à-go-go-1 (EAG1) are strongly related to carcinogenesis and tumor progression, which can be exploited for therapeutic purposes. EAG1 activity may be reduced by preventing its phosphorylation with epidermal growth factor receptor (EGFR) kinase inhibitors and by astemizole, which blocks the channel pore and downregulates its gene expression. Objective We aimed to study the potential cooperative antiproliferative effect of the EGFR inhibitor gefitinib and the EAG1-blocker astemizole, in breast cancer cells. Materials and Methods The cells were characterized by immunocytochemistry. Inhibitory concentrations were determined by non-linear regression analysis using dose-response curves. The nature of the pharmacological effect was evaluated by the combination index equation while cell cycle analysis was studied by flow cytometry. Results Astemizole and gefitinib inhibited cell proliferation in a concentration-dependent manner, with inhibitory concentrations (IC 50) values of 1.72 µM and 0.51 µM, respectively. All combinations resulted in a synergistic antiproliferative effect. The combination of astemizole and gefitinib diminished the percentage of cells in G2/M and S phases, while increased accumulation in G0/G1 of the cell cycle. Conclusions Astemizole and gefitinib synergistically inhibited proliferation in breast cancer cells expressing both EGFR and EAG1. Our results suggest that the combined treatment increased cell death by targeting the oncogenic activity of EAG1.

Role of EZH2 Inhibitor Combined with Gefitinib in EGFR-TKIs Resistant Lung Cancer Cells / 中国肺癌杂志

BACKGROUND@#Lung cancer is one of the common malignant tumors that impair human health. With the development of epigenetics, the researchers found that enhancer of Zeste homolog 2 (EZH2) is highly expressed in lung cancer tissue and its expression is closely related to the prognosis. EZH2 inhibitor can also enhance the sensitivity of tumor cells to a variety of anti-tumor drugs. The purpose of this study is to investigate the effect of combination of EZH2 inhibitor and gefitinib on the proliferation, apoptosis and migration of Gefitinib-resistant lung cancer cells.@*METHODS@#PC9 and PC9/AB2 cells were used for this study. CCK-8 and EdU experiment were used to detect combined treatment on cell viability and proliferation activity; Wound healing assay and Transwell chamber experiment were used to determine the effects of combination therapy on cell migration ability; Flow cytometry was used to detect the effect of combination therapy on EZH2 and apoptosis; Western blot was used to observe the effect of combination therapy on epidermal growth factor receptor (EGFR) signaling pathway-related proteins expression.@*RESULTS@#In gefitinib-resistant cell line PC9/AB2, gefitinib combined with EZH2 inhibitor GSK343 can significantly inhibit cell viability, reduce cell migration and increase cell apoptosis. At the same time, combination therapy can significantly inhibit the expression of EZH2 and phosphorylation EGFR proteins.@*CONCLUSIONS@#The combination of EZH2 inhibitor GSK343 and gefitinib sensitize PC9/AB2 cell to gefitinib response. This study also suggests that synergistic therapy plays a role in the reversal of EGFR-tyrosine kinase inhibitor (EGFR-TKIs) resistance in lung cancer.

Effect of down-regulation of growth arrest and DNA damage inducible protein 45β on PC9 lung adenocarcinoma cells / 中南大学学报(医学版)

To explore the effect of down-regulation of growth arrest and DNA damage inducible protein 45β (GADD45β) on the PC9 lung adenocarcinoma cells.
 Methods: GADD45β gene siRNA sequence was designed and synthesized, which was transfected into PC9 lung adenocarcinoma cells through lentivirus transfection. Quantitative real-time PCR (qRT-PCR) and Western blot are used to examine the mRNA and protein levels of GADD45β in PC9 cells before and after the transfection. Annexin V-allophycocyanin (APC) double-staining flow cytometry was used to detect the apoptosis level after the transfection. The intracellular DNA content after transfection was detected by flow cytometry. The percentage of the cells at each period of cell cycle was calculated, and the effect of RNA interference on the cell growth were analyzed. The effects of RNA interference on the tumor-formation ability of cells were tested by counting the number of clones. MTT assay was used to test the half maximal inhibitory concentration (IC50) of PC9 cells for gefitinib. 
 Results: The 5'-AAATCCACTTCACGCTCAT-3' sequence was identified as the effective sequence for GADD45β gene RNA interference. The mRNA and protein expression levels of GADD45β were markedly decreased (both P<0.05) at 48 h after transfection of GADD45β-siRNA, which resulted in the increased apoptosis rate (P<0.05), decreased tumor clone number (P<0.05) and increased percentage of PC9 cell at the S stage and G2/M stage (P<0.05). The IC50 for gefitinib was decreased obviously (P<0.05).
 Conclusion: Down-regulation of GADD45β can reduce the colony-forming ability of PC9 cells, promote the cell apoptosis, and enhance the sensitivity of PC9 cells to gefitinib.

Clinical Observation of Gefitinib with Pericardial Perfusion for Advanced Non-small Cell Lung Cancer / 中国肺癌杂志

BACKGROUND@#Epidermal growth factor receptor (EGFR) mutation non-small cell lung cancer (NSCLC) is an important subtype of lung cancer. The incidence of malignant pericardial effusion (MPCE) in EGFR-mutant NSCLC patients is high. However, there are few researches on the treatmentof this type of patients.@*METHODS@#We collected data on clinical characteristics and treatment of advanced NSCLC patients who harboring EGFR mutants and MPCE between January 2010 and December 2016. The treatments were divided into three groups: oral gefitinib combined with pericardial perfusion of hydroxycamptotheci (HCPT) group (gefitinib/HCPT); intravenous chemotherapy combined with pericardial perfusion of HCPT group (chemotherapy/HCPT) and gefitinib monotherapy group. And we retrospectively analyzed patients' outcomes in three groups.@*RESULTS@#In 273 advanced NSCLC patients with EGFR mutations, 29 cases had pericardial effusion, among which 6 patients with small amount of pericardial effusion were excluded, and 23 patients were analyzed. Median pericardium progression free survival (PFS) was 247 days. PFS for gefitinib/HCPT group (460 days) was superior to PFS for chemotherapy/HCPT group (94 days, P=0.008) and gefitinib monotherapy group (131 days, P=0.032). As for the efficacy of primary pulmonary lesions, the efficacy in gefitinib/ HCPT group was superior to chemotherapy/HCPT group [objective response rate (ORR): 33.3% vs 12.5%; disease control rate (DCR): 86.7% vs 62.5%]. There is no difference of ORR and DCR between gefitinib/HCPT group and gefitinib monotherapy group. No obvious adverse reaction was observed in all three groups.@*CONCLUSIONS@#First-line gefitinib therapy combined with pericardial perfusion of HCPT can improve pericardium PFS for advanced NSCLC patients who harboring EGFR mutants andmalignantpericardial effusion. This finding should be confirmed further through multicenter, prospective clinical trials with large sample size.

Expression of Acetaldehyde Dehydrogenase in Gefitinib-resistant Human Lung Adenocarcinoma HCC-827/GR Cells / 中国肺癌杂志

BACKGROUND@#Tumor recurrence and drug resistance are the main causes of death in tumor patients. The family of acetaldehyde dehydrogenase (ALDH) is closely related to the proliferation, migration, invasion and resistance of tumor cells, and different ALDH subtypes are expressed in different tumor cells. The aim of this study is to elucidate the ALDH subtype in human lung adenocarcinoma HCC-827/GR cells, which resistant to the gefitinib.@*METHODS@#The human lung adenocarcinoma HCC-827 cells were used to generate the gefitinib-resistant HCC-827/GR cells; the expression of ALDH subtype in either HCC-827 or HCC-827/GR was detected by flow cytometry; The proliferative capacity and sensitivity to gefitinib of hcc-827/GR cells were analyzed by MTT assay before and after treatment with 100 μmol/L diethyllaminaldehyde (DEAB); Real-time quantitative PCR was used to detect the expression of ALDH subtypes at mRNA levels in hcc-827 cells and hcc-827/GR cells.@*RESULTS@#Compared with HCC-827 cells, the positive rate of ALDH in HCC-827/GR cells increased. The proliferation ability of HCC-827/GR cells decreased after treatment with 100 μmol/L DEAB. Compared with HCC-827 cells, the expression of ALDH1A1 and ALDH1L1 mRNA was increased in hcc-827/GR cells, but the ALDH3B2 expression was decreased.@*CONCLUSIONS@#ALDH might be used as a molecular biomarker to test the gefitinib-resistant to lung adenocarcinoma cancer cells, and the ALDH1A1 may play a role in gefitinib resistance in lung cancer.

Bevacizumab and gefitinib enhanced whole-brain radiation therapy for brain metastases due to non-small-cell lung cancer

Non-small-cell lung cancer (NSCLC) patients who experience brain metastases are usually associated with poor prognostic outcomes. This retrospective study proposed to assess whether bevacizumab or gefitinib can be used to improve the effectiveness of whole brain radiotherapy (WBRT) in managing patients with brain metastases. A total of 218 NSCLC patients with multiple brain metastases were retrospectively included in this study and were randomly allocated to bevacizumab-gefitinib-WBRT group (n=76), gefitinib-WBRT group (n=77) and WBRT group (n=75). Then, tumor responses were evaluated every 2 months based on Response Evaluation Criteria in Solid Tumors version 1.0. Karnofsky performance status and neurologic examination were documented every 6 months after the treatment. Compared to the standard WBRT, bevacizumab and gefitinib could significantly enhance response rate (RR) and disease control rate (DCR) of WBRT (P<0.001). At the same time, RR and DCR of patients who received bevacizumab-gefitinib-WBRT were higher than those who received gefitinib-WBRT. The overall survival (OS) rates and progression-free survival (PFS) rates also differed significantly among the bevacizumab-gefitinib-WBRT (48.6 and 29.8%), gefitinib-WBRT (36.7 and 29.6%) and WBRT (9.8 and 14.6%) groups (P<0.05). Although bevacizumab-gefitinib-WBRT was slightly more toxic than gefitinib-WBRT, the toxicity was tolerable. As suggested by prolonged PFS and OS status, bevacizumab substantially improved the overall efficacy of WBRT in the management of patients with NSCLC.