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.

Potential life years not saved due to lack of access to anti-EGFR tyrosine kinase inhibitors for lung cancer treatment in the Brazilian public healthcare system: Budget impact and strategies to improve access. A pharmacoeconomic study

ABSTRACT BACKGROUND: Lung cancer is the fourth most common cancer in Brazil. In the 2000s, better understanding of molecular pathways led to development of epidermal growth factor receptor (EGFR)-targeted treatments that have improved outcomes. However, these treatments are unavailable in most Brazilian public healthcare services (Sistema Único de Saúde, SUS). OBJECTIVE: To assess the potential number of years of life not saved, the budget impact of the treatment and strategies to improve access. DESIGN AND SETTING: Pharmacoeconomic study assessing the potential societal and economic impact of adopting EGFR-targeted therapy within SUS. METHODS: We estimated the number of cases eligible for treatment, using epidemiological data from the National Cancer Institute. We used data from a single meta-analysis and from the Lung Cancer Mutation Consortium (LCMC) study as the basis for assessing differences in patients' survival between use of targeted therapy and use of chemotherapy. The costs of targeted treatment were based on the national reference and were compared with the amount reimbursed for chemotherapy through SUS. RESULTS: There was no life-year gain with EGFR-targeted therapy in the single meta-analysis (hazard ratio, HR, 1.01). The LCMC showed that 1,556 potential life-years were not saved annually. We estimated that the annual budget impact was 125 million Brazilian reais (BRL) with erlotinib, 48 million BRL with gefitinib and 52 million BRL with afatinib. Their incremental costs over chemotherapy per life-year saved were 80,329 BRL, 31,011 BRL and 33,225 BRL, respectively. A drug acquisition discount may decrease the budget impact by 30% (with a 20% discount). A fixed cost of 1,000 BRL may decrease the budget impact by 95%. CONCLUSION: Reducing drug acquisition costs may improve access to EGFR-targeted therapy for lung cancer.

Bevacizumab Combined with Icotinib Overcomes Osimertinib Resistance in a Patient of Non-Small Cell Lung Cancer / 中国医学科学杂志(英文版)

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.

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.

Medullary thyroid carcinoma - Adverse events during systemic treatment: risk-benefit ratio

ABSTRACT Medullary thyroid carcinoma (MTC) is a rare neuroendocrine tumor originating from parafollicular C cells of the thyroid and associated with mutations in the proto-oncogene REarranged during Transfection (RET). The prognosis of MTC depends on clinical stage, with a 95.6% 10-year survival rate among patients with localized disease and 40% among patients with advanced disease. Standard chemotherapy and radiotherapy have no significant impact on the overall survival of these patients and two tyrosine kinase receptor inhibitors (TKIs), vandetanib and cabozantinib, have been recently approved for the systemic treatment of locally advanced or metastatic MTC. However, since patients with MTC and residual or recurrent disease may have an indolent course with no need for systemic treatment, and since these drugs are highly toxic, it is extremely important to select the patients who will receive these drugs in a correct manner. It is also essential to carefully monitor patients using TKI regarding possible adverse effects, which should be properly managed when occurring.

Prophylactic effects of alpha-blockers, Tamsulosin and Alfuzosin, on postoperative urinary retention in male patients undergoing urologic surgery under spinal anaesthesia

ABSTRACT Purpose Postoperative urinary retention (POUR) is one of the most common complications after surgical procedures under spinal anaesthesia. Recent studies have shown the beneficial effects of alpha-adrenergic blockers in preventing POUR. The aim of this prospective study was to investigate and compare the prophylactic effects of tamsulosin and alfuzosin on POUR after urologic surgical procedures under spinal anaesthesia. Materials and Methods A total of 180 males who underwent elective urologic surgery were included in this study. The patients were randomly allocated into three Groups. The Group I received placebo. Patients in Group II were given 0.4mg of tamsulosin orally 14 and 2 hours before surgery. Patients in Group III were given 10mg of alfuzosin ER orally 10 and 2 hours before surgery. All patients were closely followed for 24 hours postoperatively and their episodes of urinary retentions were recorded. Results There were 60 patients in each Group. Their mean age was 35.95±15.16 years. Fifteen patients in Group I (25%), 3 patients in Group II (5%) and 4 patients in Group III (6.7%) required catheterization because of urinary retention. In tamsulosin group and alfuzosin group, there were a significantly lower proportion of patients with POUR compared with the placebo Group (p=0.002 and p=0.006). The beneficial effects of tamsulosin and alfuzosin on POUR were similar between both Groups (p=0.697). Conclusion This study suggests that the use of prophylactic tamsulosin or alfuzosin can reduce the incidence of urinary retention and the need for catheterization after urologic surgical procedures under spinal anaesthesia.

Identifying activating mutations in the EGFR gene: prognostic and therapeutic implications in non-small cell lung cancer / Identificação de mutações ativadoras no gene EGFR: implicações no prognóstico e no tratamento do carcinoma pulmonar de células não pequenas

AbstractLung cancer is the leading cause of cancer-related deaths worldwide. Promising new therapies have recently emerged from the development of molecular targeted drugs; particularly promising are those blocking the signal transduction machinery of cancer cells. One of the most widely studied cell signaling pathways is that of EGFR, which leads to uncontrolled cell proliferation, increased cell angiogenesis, and greater cell invasiveness. Activating mutations in the EGFR gene (deletions in exon 19 and mutation L858R in exon 21), first described in 2004, have been detected in approximately 10% of all non-squamous non-small cell lung cancer (NSCLC) patients in Western countries and are the most important predictors of a response to EGFR tyrosine-kinase inhibitors (EGFR-TKIs). Studies of the EGFR-TKIs gefitinib, erlotinib, and afatinib, in comparison with platinum-based regimens, as first-line treatments in chemotherapy-naïve patients have shown that the EGFR-TKIs produce gains in progression-free survival and overall response rates, although only in patients whose tumors harbor activating mutations in the EGFR gene. Clinical trials have also shown EGFR-TKIs to be effective as second- and third-line therapies in advanced NSCLC. Here, we review the main aspects of EGFR pathway activation in NSCLC, underscore the importance of correctly identifying activating mutations in the EGFR gene, and discuss the main outcomes of EGFR-TKI treatment in NSCLC.

ResumoO câncer de pulmão é a principal causa de mortes por câncer no mundo. Recentemente, novas estratégias promissoras de tratamento foram criadas a partir do desenvolvimento de terapias de alvo molecular, particularmente aquelas que interferem em vias de transdução de sinais em células neoplásicas. Uma das vias de transdução de sinais mais estudadas é aquela ativada a partir do EGFR, que leva a perda do controle da proliferação celular, aumento da angiogênese celular e aumento da capacidade de invasão celular. Mutações ativadoras no EGFR (deleções no éxon 19 e mutação L858R no éxon 21), primeiramente descritas em 2004, foram detectadas em aproximadamente 10% dos pacientes com carcinoma de pulmão de células não pequenas (CPCNP) não escamoso em países ocidentais e são os fatores preditivos mais importantes de resposta aos tyrosine-kinase inhibitors (inibidores de tirosina quinase) do EGFR (EGFR-TKIs). Estudos de tratamento de primeira linha com esses EGFR-TKIs (gefitinibe, erlotinibe e afatinibe) em pacientes sem tratamento sistêmico prévio, em comparação com regimes baseados em platinas, têm demonstrado que os EGFR-TKIs resultam em ganhos em sobrevida livre de progressão e taxas globais de resposta, embora somente em pacientes cujos tumores alberguem mutações ativadoras no EGFR. Ensaios clínicos também mostraram a efetividade dos EGFR-TKIs como tratamentos de segunda e terceira linha de CPCNP avançado. Neste artigo, revisamos os principais aspectos da ativação da via do EGFR em CPCNP, reforçamos a importância da identificação correta das mutações ativadoras no EGFR e discutimos os principais resultados do tratamento do CPCNP com EGFR-TKIs.

Rapid response of hypercortisolism to vandetanib treatment in a patient with advanced medullary thyroid cancer and ectopic Cushing syndrome

Medullary thyroid carcinoma (MTC) may rarely present with paraneoplastic syndromes. Among the most frequent ones are the appearance of diarrhea and ectopic Cushing syndrome (ECS). The ECS in the context of MTC is usually present in patients with distant metastatic disease. The use of drugs such as ketoconazole, metyrapone, somatostatin analogs and etomidate have been ineffective alternatives to control hypercortisolism in these patients. Bilateral adrenalectomy is often required to manage this situation. Recently, the use of tyrosine kinase inhibitors has been shown to be a useful tool to achieve eucortisolism in patients with metastatic MTC and ECS. We present a patient with sporadic advanced persistent and progressive MTC with lymph node and liver metastases, which after 16 years of follow-up developed an ECS. After one month of 300 mg/day vandetanib treatment, a biochemical and clinical response of the ECS was achieved but it did not result in significant reduction of tumor burden. However the patient reached criteria for stable disease according to response evaluation criteria in solid tumors (RECIST 1.1) after 8 months of follow-up.

The impact of erlotinib use in non-small-cell lung cancer patients treated in a private reference general hospital and in a private cancer clinic from 2005 to 2011 / O impacto do uso do erlotinibe em pacientes portadores de neoplasia de pulmão de não pequenas células tratados em um hospital geral de referência e clínica particular de oncologia no período de 2005 a 2011

ABSTRACT Objective: To report the demographic data and clinical outcomes of non-small-cell lung cancer patients exposed to erlotinib in any line of treatment. Methods: This was a retrospective cohort study of nonsmall-cell lung cancer patients from a reference general hospital and a private oncology clinic, who received erlotinib from 2005 to 2011. Statistical analysis was performed and we evaluated demographic data and response to treatment, by correlating the results of this first cohort published in Brazil with results of current literature. Results: A total of 44 patients were included; 65.9% were diagnosed with adenocarcinoma, and 63.6% had metastatic disease. The mean age was 63.3 years. The median follow-up was 47.9 months. Epidermal growth factor receptor mutation screening was performed in 22.7% of patients (n=10), with mutation present in 30% of patients. The median overall survival was 46.3 months, and there was a higher probability of survival at 60 months for females compared to males (29.4% versus 15.8%; p=0.042). The other variables did not present significant statistical difference. Conclusion: We collected the largest cohort of patients with non-small-cell lung cancer who have used erlotinib in Brazil to date, and demonstrated that outcomes of patients treated at our clinic during the study period were consistent with the results of current literature in similar patients. .

RESUMO Objetivo: Relatar as características demográficas e a evolução de pacientes com neoplasia de pulmão de não pequenas células que receberam erlotinibe em qualquer linha de tratamento. Métodos: Coletamos retrospectivamente dados de pacientes portadores de neoplasia de pulmão de não pequenas células que receberam erlotinibe em qualquer linha de tratamento em um hospital geral de referência e em uma clínica particular de oncologia em São Paulo, no período de 2005 a 2011. Foi realizada a análise estatística e foram avaliados aspectos demográficos e resposta ao tratamento estabelecido, correlacionando os resultados dessa primeira coorte publicada no Brasil com resultados da literatura vigente. Resultados: Foram avaliados 44 pacientes, dos quais 65,9% eram portadores de adenocarcinoma e 63,6% tinham doença metastática. A média de idade foi de 63,3 anos. O seguimento mediano foi de 47,9 meses. A pesquisa de mutação do receptor do fator de crescimento epidérmico foi realizada em 22,7% dos pacientes (n=10), resultando positiva em 30% dos avaliados. A sobrevida global mediana foi de 46,3 meses, e observou-se uma probabilidade maior de sobrevida em 60 meses para o grupo feminino, quando comparado ao grupo masculino (29,4% versus 15,8%; p=0,042). As demais variáveis não apresentaram diferença estatística significativa. Conclusão: Coletamos a maior sequência de pacientes com neoplasia de pulmão de não pequenas células que fizeram uso de erlotinibe no Brasil até a data vigente e demonstramos que a evolução dos pacientes tratados no período avaliado teve resultados concordantes com os da literatura vigente em pacientes semelhantes. .

Clinical efficacy of erlotinib, a salvage treatment for non-small cell lung cancer patients following gefitinib failure

BACKGROUND/AIMS: The purpose of this study was to identify predictive factors for erlotinib treatment in non-small cell lung cancer (NSCLC) patients following gefitinib failure. METHODS: Forty-five patients with NSCLC who were treated with erlotinib following gefitinib failure at Seoul National University Hospital between August 2005 and November 2011 were enrolled. Epidermal growth factor receptor (EGFR) mutation status, pathologic findings and other clinical factors, including response to tyrosine kinase inhibitors (TKIs) and progression-free survival (PFS), were evaluated. RESULTS: Of the 45 patients, 40 patients (88.8%) had adenocarcinoma. The following EGFR mutations were observed: five patients with a deletion of exon 19, six patients with an L858R mutation, three patients with wild-type EGFR, and 31 patients with unknown mutations. The response rate of erlotinib was 4.4%, and stable disease was 42.2%. The median PFS for erlotinib was 2.6 months (95% confidence interval, 1.4 to 3.7). Patients with a PFS > or = 4 months during previous gefitinib treatment had a significantly longer PFS with erlotinib (3.3 months vs. 1.6 months, respectively; p or = 4 months for previous gefitinib treatment was significantly associated with prolonged PFS with erlotinib (p = 0.04). However, the response rate of gefitinib and treatment sequence were not associated with prolonged PFS with erlotinib (p = 0.28 and p = 0.67, respectively). CONCLUSIONS: Following rechallenge with the EGFR TKI erlotinib following gefitinib failure, patients who showed prolonged PFS with gefitinib benefit from erlotinib. However, further prospective studies are needed to confirm these findings.

An important role for peroxiredoxin II in survival of A549 lung cancer cells resistant to gefitinib

Redox adaptation is an important concept that explains the mechanisms by which cancer cells survive under persistent endogenous oxidative stress and become resistant to certain anticancer agents. To investigate this concept, we determined the expression levels of peroxiredoxins (Prxs), antioxidant enzymes in drug-resistant non-small cell lung carcinoma cells. Prx II was remarkably increased only in A549/GR (gefitinib-resistant) cells compared with A549 cells, consistent with methylation/demethylation. Prx II was highly methylated in the A549 cells but was demethylated in the A549/GR cells. The elevated expression of Prx II resulted in the downregulation of reactive oxygen species (ROS) and cell death and upregulation of cell cycle progression in the A549/GR cells. When Prx II mRNA in the A549/GR cells was knocked down, the levels of ROS and apoptosis were significantly recovered to the levels of the controls. In addition, signaling molecules involved in apoptosis were increased in the A549/GR-shPrx II cells. There was no difference in the expression of MAPK/ERK between the A549/GR cells and A549/GR-shPrx II cells, but the phosphorylation of JNK was increased in the A549/GR cells and was markedly decreased in the A549/GR-shPrx II cells. Colony number and tumor growth were significantly decreased in the A549/GR-shPrx II cells compared with the A549/GR cells. Our findings suggest that Prx II has an important role in cancer cell survival via the modulation of signaling molecules involved in apoptosis and the phosphorylation of JNK by the downregulation of ROS levels in A549/GR cells.

An important role for peroxiredoxin II in survival of A549 lung cancer cells resistant to gefitinib

Redox adaptation is an important concept that explains the mechanisms by which cancer cells survive under persistent endogenous oxidative stress and become resistant to certain anticancer agents. To investigate this concept, we determined the expression levels of peroxiredoxins (Prxs), antioxidant enzymes in drug-resistant non-small cell lung carcinoma cells. Prx II was remarkably increased only in A549/GR (gefitinib-resistant) cells compared with A549 cells, consistent with methylation/demethylation. Prx II was highly methylated in the A549 cells but was demethylated in the A549/GR cells. The elevated expression of Prx II resulted in the downregulation of reactive oxygen species (ROS) and cell death and upregulation of cell cycle progression in the A549/GR cells. When Prx II mRNA in the A549/GR cells was knocked down, the levels of ROS and apoptosis were significantly recovered to the levels of the controls. In addition, signaling molecules involved in apoptosis were increased in the A549/GR-shPrx II cells. There was no difference in the expression of MAPK/ERK between the A549/GR cells and A549/GR-shPrx II cells, but the phosphorylation of JNK was increased in the A549/GR cells and was markedly decreased in the A549/GR-shPrx II cells. Colony number and tumor growth were significantly decreased in the A549/GR-shPrx II cells compared with the A549/GR cells. Our findings suggest that Prx II has an important role in cancer cell survival via the modulation of signaling molecules involved in apoptosis and the phosphorylation of JNK by the downregulation of ROS levels in A549/GR cells.

Epidermal growth factor receptor (EGFR) mutations in lung cancer: preclinical and clinical data

Lung cancer leads cancer-related mortality worldwide. Non-small-cell lung cancer (NSCLC), the most prevalent subtype of this recalcitrant cancer, is usually diagnosed at advanced stages, and available systemic therapies are mostly palliative. The probing of the NSCLC kinome has identified numerous nonoverlapping driver genomic events, including epidermal growth factor receptor (EGFR) gene mutations. This review provides a synopsis of preclinical and clinical data on EGFR mutated NSCLC and EGFR tyrosine kinase inhibitors (TKIs). Classic somatic EGFR kinase domain mutations (such as L858R and exon 19 deletions) make tumors addicted to their signaling cascades and generate a therapeutic window for the use of ATP-mimetic EGFR TKIs. The latter inhibit these kinases and their downstream effectors, and induce apoptosis in preclinical models. The aforementioned EGFR mutations are stout predictors of response and augmentation of progression-free survival when gefitinib, erlotinib, and afatinib are used for patients with advanced NSCLC. The benefits associated with these EGFR TKIs are limited by the mechanisms of tumor resistance, such as the gatekeeper EGFR-T790M mutation, and bypass activation of signaling cascades. Ongoing preclinical efforts for treating resistance have started to translate into patient care (including clinical trials of the covalent EGFR-T790M TKIs AZD9291 and CO-1686) and hold promise to further boost the median survival of patients with EGFR mutated NSCLC.

Transformation into large-cell neuroendocrine carcinoma associated with acquired resistance to erlotinib in nonsmall cell lung cancer

No abstract available.

A Case of Residual Non-Small Cell Lung Cancer Cells Coexisting With Newly Developed Small Cell Lung Cancer Cells in Ascitic Fluid after Chemotherapy for Non-Small Cell Lung Cancer

No abstract available.

Post-Progression Survival in Patients with Non-Small Cell Lung Cancer with Clinically Acquired Resistance to Gefitinib

Most patients with tyrosine kinase inhibitor (TKI)-sensitive non-small cell lung cancer (NSCLC) eventually develop acquired resistance to TKIs. Factors that affect TKI-sensitive patient survival after progression during TKI treatment remain unknown. We attempted to identify factors that affected post-progression survival. We retrospectively reviewed 81 advanced NSCLC patients with disease progression following tumor response and durable (> or = 6 months) disease stabilization with first-line or second-line gefitinib. Post-progression survival (PPS) and characteristics were investigated and compared in patients who did (n = 16) and did not (n = 65) resume TKIs. Most patients were female never-smokers with adenocarcinoma. Median overall PPS was 10.3 months (95% confidence interval [CI], 7.458-13.142). Age, gender, smoking history, histology, Eastern Cooperative Oncology Group performance status at gefitinib initiation, initial stage, and platinum-based chemotherapy after gefitinib were not significant predictors of PPS. Pemetrexed use after gefitinib significantly improved PPS (18.5 vs 8.6 months; hazard ratio [HR], 0.45; P = 0.008). Gefitinib reuse tended to lengthen PPS but was insignificant in multivariate analysis (27.4 vs 8.8 months; HR, 0.53; P = 0.095). NSCLC patients assumed to have clinically acquired resistance to TKIs had relatively long PPS. TKIs reuse or pemetrexed use after progression with gefitinib may improve PPS.

A case report: successful treatment of meningeal metastasis with concurrent whole brain radiotherapy and erlotinib in a patient with non-small cell lung cancer / Reporte de caso: tratamiento exitoso de una metástasis meníngea con radioterapia total concurrente del cerebro y erlotinib en un paciente con cáncer pulmonar de células no pequeñas

We report a case of successful treatment with erlotinib of a patient with non-small cell lung cancer (stage IV) and meningeal metastasis. Combined treatment with whole brain radiotherapy (WBRT) and erlotinib mitigated neurologic symptoms of the patient. Magnetic resonance imaging showed reduction of the brain metastasis. Partial remission was observed by chest computed tomography (CT) scan after six months of erlotinib therapy.

Reportamos un caso de tratamiento exitoso con el erlotinib de un paciente con cáncer pulmonar de células no pequeñas (fase IV) y metástasis meníngea. El tratamiento combinado con la radioterapia total del cerebro (WBRT) y erlotinib mitigaron los síntomas neurológicos del paciente. Las imágenes de resonancia magnética mostraron una reducción de la metástasis del cerebro. La remisión parcial fue observada mediante CT scan de tórax tras seis meses de terapia con erlotinib.

Kinase inhibitors for advanced medullary thyroid carcinoma

The recent availability of molecular targeted therapies leads to a reconsideration of the treatment strategy for patients with distant metastases from medullary thyroid carcinoma. In patients with progressive disease, treatment with kinase inhibitors should be offered.

Retrospective Study of Gefitinib as a Second Line Treatment in Lung Cancer.

Objective: To find out response of Gefitinib in terms of overall survival in advanced non small cell carcinoma lung progressed after primary treatment. Methods: It is a retrospective study of clinical data experienced with use of Gefitinib as a second line treatment of advanced non small cell carcinoma lung progressed after primary treatment from period of March 2007 to March 2009 in Burdwan Medical College and Hospital at Department of Radiotherapy (Oncology). Results: Among patients treated with Gefitinib (n – 37) median overall survival was 9.6 months whereas, patients treated with placebo median survival was 5.3 months. There is a significant survival advantage ( p < 0.001) in Gefitinib group. Conclusion: Gefitinib is a well tolerated drug and it has a significant survival advantage in advanced non small cell carcinoma lung progressive after primary treatment.