The efficacy of pemetrexed as a third- or fourth-line therapy and the significance of thymidylate synthase expression in patients with advanced non-small cell lung cancer

miR-145-5p Targets Sp1 in Non-Small Cell Lung Cancer Cells and Links to BMI1 Induced Pemetrexed Resistance and Epithelial-Mesenchymal Transition

Pemetrexed is a folic acid inhibitor used as a second-line chemotherapeutic agent for the treatment of locally advanced or metastatic non-small cell lung cancer (NSCLC), which accounts for 85% of lung cancers. However, prolonged treatment with pemetrexed may cause cancer cells to develop resistance. In this study, we found increased expressions of BMI1 (B Lymphoma Mo-MLV insertion region 1 homolog) and Sp1 and a decreased expression of miR-145-5p was found in pemetrexed-resistant A400 cells than in A549 cells. Direct Sp1 targeting activity of miR-145-5p was demonstrated by a luciferase based Sp1 3'-UTR reporter. Changed expression of miR-145-5p in A400 or A549 cells by transfection of miR-145-5p mimic or inhibitor affected the sensitivity of the cells to pemetrexed. On the other hand, the overexpression of Sp1 in A549 cells caused the decreased sensitivity to pemetrexed, induced cell migratory capability, and epithelial-mesenchymal transition (EMT) related transcription factors such as Snail Family Transcriptional Repressor 1 and Zinc Finger E-Box Binding Homeobox 1. In addition, the overexpression of BMI1 in the A549 cells resulted in an increase in Sp1 and a decrease in miR-145-5p accompanied by the elevations of cell proliferation and EMT transcription factors, which could be reduced by the overexpression of miR-145-5p or by treatment with the Sp1 inhibitor of mithramycin A. In conclusion, the results of this study suggest that the downregulation of miR-145-5p by BMI1 overexpression could lead to the enhanced expression of Sp1 to induce the EMT process in pemetrexed-resistant NSCLC cells. These results suggest that increasing miR-145-5p expression by delivering RNA drugs may serve as a sensitizing agent for pemetrexed-resistant NSCLC patients.

Mechanisms of resistance to pemetrexed in non-small cell lung cancer

Currently, lung cancer has remained the most common cause of cancer death while non-small cell lung cancer (NSCLC) accounts for the most of all lung cancer cases. Regardless of multiple existing managements, chemotherapy regimens are still the mainstay of treatment for NSCLC, where pemetrexed has shown cytotoxic activity and has increasingly been used, especially for advanced cases. However, chemo-resistance may inhibit clinical efficacy after long-term use. Mechanisms responsible for chemo-resistance to pemetrexed in NSCLC are plethoric but can be separated into two categories to be discussed: tumor cells and their interactions with drugs. Phenomena relevant to tumor cells such as oncogene or oncoprotein alterations, DNA synthesis, DNA repair, and tumor cell biology behavior are discussed, as well as processes associated with drug dynamics, including drug uptake, drug elimination, and antifolate polyglutamylation. This review will focus on clinical trials and the basic biomedical mechanisms of NSCLC treated with pemetrexed and will describe the underlying mechanisms of resistance to facilitate more efficient clinical therapies to treat patients.

Efficacy of Vinorelbine Monotherapy as Third- or Further-Line Therapy in Patients with Advanced Non-Small-Cell Lung Cancer

BACKGROUND

The survival rate of patients with lung cancer has increased significantly over the years, but there has been no further progress in third- or fourth-line therapy. We investigated the efficacy and tolerability of monotherapy with weekly vinorelbine, a semi-synthetic vinca alkaloid, in advanced non-small-cell lung cancer (NSCLC) patients who had previously been treated several times.

METHODS

In all, 159 NSCLC patients who received vinorelbine monotherapy as third- or further-line therapy between January 2008 and July 2017 were included in this study. Patients received vinorelbine intravenously at a dose of 25-30 mg/m2/week.

RESULTS

Their mean age was 62.4 years. The histologic types of tumor were adenocarcinoma (50.9%), squamous cell carcinoma (42.8%), and others (6.2%). The overall response rate was 19.5% (31/159). The median progression-free survival (PFS) was 3.0 months (95% confidence interval [CI] 2.5-3.5 months), and the median overall survival (OS) after vinorelbine use was 7.6 months (95% CI 6.2-9.0 months). Vinorelbine therapy showed significantly higher efficacy in patients with adenocarcinoma, and these patients had a longer PFS than patients with other types of cancer. Patients who received vinorelbine as fifth- or further-line treatment had a higher response rate and longer PFS and OS than those who received vinorelbine as third- or fourth-line treatment.

CONCLUSIONS

Weekly vinorelbine monotherapy may be a feasible therapeutic option for patients with heavily treated, advanced NSCLC, particularly lung adenocarcinoma.

Enhancing chemoradiation of colorectal cancer through targeted delivery of raltitrexed by hyaluronic acid coated nanoparticles

Combined modality therapy incorporating raltitrexed (RTX), a thymidylate synthase inhibitor, and radiation can lead to improved outcome for rectal cancer patients. To increase delivery and treatment efficacy, we formulated a hyaluronic acid (HA) coated nanoparticle encapsulating RTX (HARPs) through layer-by-layer assembly. These particles were determined to have a diameter of ∼115 nm, with a polydispersity index of 0.112 and a zeta potential of -22 mV. Cell uptake in CT26 cells determined through flow cytometry showed a ∼5-fold increase between untargeted and HA-coated particles. Through viability and DNA damage assays, we assessed the potency of the free RTX and HARPs, and found increased DNA damage in cells treated with the RTX-loaded nanoparticles administered concurrently with radiation. In vivo efficacy through tumor growth inhibition was investigated in a syngeneic murine colorectal cancer model. Nanoparticle treatment showed no acute toxicity in vivo, and all treatments showed survival benefits for their respective groups compared to controls. HARPs alone slowed tumor growth, although not significantly. Radiation alone and in combination with the HARPs showed significant growth delay. Notably, the combination treatment significantly hindered tumor progression relative to the HARPs highlighting the benefit of this multipronged treatment. These results provide a foundation for loading RTX in a nanoparticle formulation, and establish a combined radiation and drug dosing schedule to determine optimal tumor growth delay and subsequent treatment efficacy.

Novel drug-resistance mechanisms of pemetrexed-treated non-small cell lung cancer

Pemetrexed (PEM) improves the overall survival of patients with advanced non-small cell lung cancer (NSCLC) when administered as maintenance therapy. However, PEM resistance often appears during the therapy. Although thymidylate synthase is known to be responsible for PEM resistance, no other mechanisms have been investigated in detail. In this study, we explored new drug resistance mechanisms of PEM-treated NSCLC using two combinations of parental and PEM-resistant NSCLC cell lines from PC-9 and A549. PEM increased the apoptosis cells in parental PC-9 and the senescent cells in parental A549. However, such changes were not observed in the respective PEM-resistant cell lines. Quantitative RT-PCR analysis revealed that, besides an increased gene expression of thymidylate synthase in PEM-resistant PC-9 cells, the solute carrier family 19 member1 (SLC19A1) gene expression was markedly decreased in PEM-resistant A549 cells. The siRNA-mediated knockdown of SLC19A1 endowed the parental cell lines with PEM resistance. Conversely, PEM-resistant PC-9 cells carrying an epidermal growth factor receptor (EGFR) mutation acquired resistance to a tyrosine kinase inhibitor erlotinib. Although erlotinib can inhibit the phosphorylation of EGFR and Erk, it is unable to suppress the phosphorylation of Akt in PEM-resistant PC-9 cells. Additionally, PEM-resistant PC-9 cells were less sensitive to the PI3K inhibitor LY294002 than parental PC-9 cells. These results indicate that SLC19A1 negatively regulates PEM resistance in NSCLC, and that EGFR-tyrosine-kinase-inhibitor resistance was acquired with PEM resistance through Akt activation in NSCLC harboring EGFR mutations.

Folic acid phenotype (FAP) is a superior biomarker predicting response to pemetrexed-based chemotherapy in malignant pleural mesothelioma

BACKGROUND

Malignant pleural mesothelioma (MPM) is a rare tumor linked to a dismal prognosis. Even the most effective chemotherapeutical regime of pemetrexed combined with cisplatin leads to a remission-rate of only about 40%. The reasons for the rather poor efficacy remain largely unknown.

RESULTS

Phenotypes were significantly associated with progression (p=0.0279) and remission (p=0.0262). Cox-regression revealed significant associations between SLC19A1/TYMS-ratio (p=0.0076) as well as FPGS/TYMS-ratio (p=0.0026) and OS. For differentiation by risk-groups, COXPH identified a strong correlation (p=0.0008).

METHODS

56 MPM specimens from patients treated with pemetrexed were used for qPCR analysis. Phenotypes and risk groups were defined by their expression levels of members of the folic acid metabolism and correlated to survival and objective response.

CONCLUSION

Our results indicate that the balance between folic acid uptake, activation and metabolism plays a crucial role in response to pemetrexed-based chemotherapy and the prognosis of MPM patients. Implementing this marker profile in MPM stratification may help to individualize MPM-therapy more efficiently.

Combined effect of ERCC1 and ERCC2 polymorphisms on overall survival in non-squamous non-small-cell lung cancer patients treated with first-line pemetrexed/platinum

OBJECTIVES

Polymorphisms of DNA repair genes may affect DNA repair capacity and the sensitivity of platinum doublets chemotherapy in non-small-cell lung cancer (NSCLC). We prospectively evaluated whether single nucleotide polymorphisms (SNPs) of ERCC1, ERCC2, XRCC1, and XRCC3 were associated with treatment outcome in advanced non-squamous NSCLC patients receiving pemetrexed/platinum as their first-line chemotherapy.

MATERIALS AND METHODS

Genotyping of six SNPs in four DNA repair genes in 58 patients treated with first-line pemetrexed/platinum was performed using TaqMan SNP Genotyping Assays.

RESULTS

The wild-type ERCC1 8092 (C/C) was significantly associated with a better objective response compared to the variant genotypes (C/A + A/A) (48% vs 10%, P = .005). In the multivariate Cox proportional hazards model, we found that individuals with a wild-type genotype of ERCC1 Asn118Asn, ERCC1 C8092A and ERCC2 Asp312Asn had significantly better overall survival (OS) than those with a heterozygous or homozygous variant genotype. On the other hand, the heterozygous variant genotype of ERCC2 Lys751Gln was associated with better OS than that of the wild-type genotype. We further explored the combined effect of SNPs on OS, and found a significant allele/dose-dependent trend toward decreasing OS in patients with an increasing number of unfavorable alleles among four SNPs in ERCC1 and ERCC2. The median OS of patients with two or three unfavorable alleles (30.1 and 30.5 months, respectively) was significantly longer than that of patients with 4 unfavorable alleles (11.8 months, log-rank test for trend, P = .001).

CONCLUSION

A combination of ERCC1 and ERCC2 polymorphisms may predict OS among pemetrexed/platinum treated advanced non-squamous NSCLC patients.

Apatinib as a third- or further- line treatment in patients with advanced NSCLC harboring wild-type EGFR

Objectives

This study was conducted to evaluate the efficacy and safety of apatinib in advanced NSCLC patients with EGFR wild-type who have failed more than second-line chemotherapy.

Materials and Methods

We retrospectively analyzed patients with EGFR wild-type advanced NSCLC who were treated with apatinib from January 2014 to August 2016. Objective response rate (ORR), disease control rate (DCR), progression free survival (PFS), overall survival (OS), and adverse events (AEs) were reveiwed and evaluated. Univariate and multivariate analyses were performed to determine the prognostic factors.

Results

36 patients were evaluable for safety and efficacy. 6 patients obtained partial response, and 21 showed stable disease. The ORR and DCR were 16.7% and 75%, respectively. The median PFS and OS were 4.5 months and 8.2 months, respectively. Prognostic variable for a longer OS was good performance status (p = 0.015). Most adverse reactions were mild or moderate.

Conclusions

Apatinib should be recommended as a third- or further- line therapy in advanced NSCLC patients with EGFR wild-type due to its better efficacy and tolerable toxicity.

Etirinotecan Pegol (NKTR-102) in Third-line Treatment of Patients With Metastatic or Recurrent Non-Small-cell Lung Cancer: Results of a Phase II Study

BACKGROUND

Third-line treatment options are limited for patients with metastatic non-small-cell lung cancer (NSCLC). Etirinotecan pegol (NKTR-102) is a long-acting topoisomerase-I inhibitor. We conducted a single-arm phase II trial to evaluate its efficacy in third-line treatment.

PATIENTS AND METHODS

Patients aged ≥ 18 years with histologically proven NSCLC who had received 2 previous systemic therapy regimens, measurable disease, Eastern Cooperative Oncology Group (ECOG) performance status ≤ 1, and adequate end-organ function were eligible. Etirinotecan pegol was administered at a dose of 145 mg/m² intravenously once every 3 weeks until progression. The response was assessed every 6 weeks using Response Evaluation Criteria In Solid Tumors, version 1.1. The primary endpoint was the overall objective response rate. The secondary endpoints included progression-free survival (PFS), overall survival (OS) and safety. A Simon 2-stage design was implemented for futility.

RESULTS

From January 2013 to January 2015, 40 patients were enrolled. Their median age was 66 years (range, 19-85 years), 45% were female, 30% had an ECOG performance status of 0, 96% were current and former smokers, and 31 had adenocarcinoma. Patients received a median of 3 cycles (range, 2-15) of protocol therapy. The best response was a partial response in 2 patients. The treatment was well tolerated; 3 patients had grade 3 gastrointestinal toxicity attributable to therapy. The median PFS was 2.3 months (95% confidence interval [CI], 1.3-4.4 months), and the median OS was 7.1 months (95% CI 4.2-11.4 months).

CONCLUSIONS

Etirinotecan pegol was well tolerated and led to 2 partial responses and disease stabilization with this third-line treatment of metastatic NSCLC. However, the study failed to meet its prespecified response rate endpoint.

PD-L1 expression indicates favorable prognosis for advanced lung adenocarcinoma patients treated with pemetrexed

Conventional chemotherapy for lung cancer exerts anti-tumor effects through cytotoxicity, and through immunologic regulation by reducing specific T cell subsets and inducing the expression of programmed death ligand 1 (PD-L1) on tumor cells. Even though pemetrexed has shown huge potential in combination with other targeted or immune therapies, there is still little information about the values of specific immune checkpoint markers for advanced lung adenocarcinoma treated with pemetrexed. In the present study, a total of 56 patients with advanced lung adenocarcinoma, who received pemetrexed-based chemotherapy, were included retrospectively. Immunohistochemistry was performed to assess PD-L1, programmed death 1 (PD-1), thymidylate synthase, and tumor infiltrating lymphocytes (TILs). In this cohort, the positive expression of PD-L1 and PD-1 were 26.8% and 33.9% respectively. PD-L1, PD-1, and thymidylate synthase expression were not significantly associated with any clinical features, while the expression of both PD-L1 and PD-1 were correlated with Ki-67 expression. Furthermore, the expression of PD-1 was significantly correlated with TILs. The progression-free survival (PFS) in patients with PD-L1⁺ specimens was significantly longer compared to PD-L1^- specimens. Moreover, PD-L1 expression was an independent protective factor for PFS, and the smoking status was an independent risk factor. PD-L1 expression was significantly associated with better prognosis for patients with pemetrexed-based treatment. Our findings suggested that PD-L1 expression might be a favorable prognostic biomarker for pemetrexed-based regimen, which is a rationale for combining immunotherapy with chemotherapy for lung cancer.

PD-L1 expression indicates favorable prognosis for advanced lung adenocarcinoma patients treated with pemetrexed

Conventional chemotherapy for lung cancer exerts anti-tumor effects through cytotoxicity, and through immunologic regulation by reducing specific T cell subsets and inducing the expression of programmed death ligand 1 (PD-L1) on tumor cells. Even though pemetrexed has shown huge potential in combination with other targeted or immune therapies, there is still little information about the values of specific immune checkpoint markers for advanced lung adenocarcinoma treated with pemetrexed. In the present study, a total of 56 patients with advanced lung adenocarcinoma, who received pemetrexed-based chemotherapy, were included retrospectively. Immunohistochemistry was performed to assess PD-L1, programmed death 1 (PD-1), thymidylate synthase, and tumor infiltrating lymphocytes (TILs). In this cohort, the positive expression of PD-L1 and PD-1 were 26.8% and 33.9% respectively. PD-L1, PD-1, and thymidylate synthase expression were not significantly associated with any clinical features, while the expression of both PD-L1 and PD-1 were correlated with Ki-67 expression. Furthermore, the expression of PD-1 was significantly correlated with TILs. The progression-free survival (PFS) in patients with PD-L1⁺ specimens was significantly longer compared to PD-L1^- specimens. Moreover, PD-L1 expression was an independent protective factor for PFS, and the smoking status was an independent risk factor. PD-L1 expression was significantly associated with better prognosis for patients with pemetrexed-based treatment. Our findings suggested that PD-L1 expression might be a favorable prognostic biomarker for pemetrexed-based regimen, which is a rationale for combining immunotherapy with chemotherapy for lung cancer.

The salvage therapy in lung adenocarcinoma initially harbored susceptible EGFR mutation and acquired resistance occurred to the first-line gefitinib and second-line cytotoxic chemotherapy

Background

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) such as gefitinib can provide better efficacy and prolonged progression free survival (PFS) than cytotoxic chemotherapy for metastatic lung non-squamous cell carcinoma harboring susceptible EGFR mutations when used as first-line therapy. Cytotoxic chemotherapy is regarded as being the standard therapy to overcome acquired resistance to an initial EGFR TKI. However, there is currently no consensus on how best to treat patients who develop resistance to both an initial EGFR TKI and chemotherapy.

Methods

We enrolled stage IV lung adenocarcinoma patients with an EGFR mutation and who had developed acquired resistance to gefitinib and cytotoxic chemotherapy from two university-affiliated hospitals in Taiwan from June 2011 to December 2014. Basic demographic data, included Eastern Cooperative Oncology Group (ECOG) performance status were collected, and the response rate, progression-free survival (PFS) and overall survival (OS) were analyzed.

Result

Two hundred and nine patients with mutated EGFR and who took gefitinib as the first-line therapy were identified in the study period, of whom 86 received second-line cytotoxic chemotherapy, and 60 who received third-line therapy were eligible for this study. The patients who received cytotoxic chemotherapy had a significantly higher disease control rate than those who received erlotinib (73% vs. 46%, p = 0.0363), however there were no significant differences in PFS (2.9 months vs. 3.1 months, p = 0.9049) and OS (8.9 months vs. 7.9 months, p = 0.4956). Platinum- or pemetrexed-based chemotherapy provided similar PFS and OS as others did. The only significant poor prognostic factors for OS were old age (≥65 years) (HR = 5.97 [2.65–13.44], p < 0.0001) and poor performance status (ECOG ≥2) (HR = 5.84 [2.61–13.09], p < 0.0001).

Conclusion

Retreatment with an EGFR TKI is not inferior to cytotoxic chemotherapy when used as salvage therapy for patients with adenocarcinoma with an EGFR mutation, especially if a third-generation EGFR TKI is not available, or if the reason for resistance is unknown or is not related to the T790M mutation. Old age and poor ECOG score were both poor prognostic factors in the salvage therapy.

Subsequent treatment of epidermal growth factor receptor-tyrosine kinase inhibitor failure in patients with advanced lung adenocarcinoma

BACKGROUND

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) effectively treat advanced non-small cell lung cancer with EGFR-mutation. However, most patients develop acquired resistance without effective therapy subsequent to EGFR-TKI failure. We evaluated the efficacy of subsequent treatment strategies for EGFR-TKI resistance.

METHODS

We retrospectively analyzed 240 patients with advanced lung adenocarcinoma with EGFR-TKI failure and following subsequent treatment. According to the first subsequent strategies after EGFR-TKI failure, patients were divided into groups of EGFR-TKI continuation (21 cases), EGFR-TKI continuation with chemotherapy (23 cases), chemotherapy alone (143 cases), and best supportive care (BSC) (53 cases).

RESULTS

Except for 53 cases of BSC, the disease control rates (DCR) of the remaining 187 patients in the EGFR-TKI continuation, EGFR-TKI continuation with chemotherapy, and chemotherapy alone groups were 66.7%, 73.9%, and 44.8%, respectively. The median post-progression progression-free survival (PFS) for the three groups was 3.0, 3.3, and 2.0 months, respectively. The DCR for the EGFR-TKI continuation with chemotherapy group was significantly higher than the chemotherapy alone group (P = 0.006). The post-progression PFS of the EGFR-TKI continuation with chemotherapy group was significantly longer than the chemotherapy alone group (P = 0.037). The median overall survival in the EGFR-TKI continuation, EGFR-TKI continuation with chemotherapy, chemotherapy alone, and BSC groups were 6.9, 11.6, 8.8, and 0.9 months, respectively. Compared to the BSC group, all groups achieved a survival benefit (P < 0.001).

CONCLUSIONS

EGFR-TKI continuation with chemotherapy could provide benefits for patients with acquired resistance to EGFR-TKI.

Pharmacogenomics in the treatment of lung cancer: an update

Significant advances have been made in the analysis of the human genome in the first decades of the 21st century and understanding of tumor biology has matured greatly. The identification of tumor-associated mutations and the pathways involved has led to the development of targeted anticancer therapies. However, the challenge now in using chemotherapy to treat nonsmall-cell lung cancer is to identify more molecular markers predictive of drug sensitivity and determine the optimal drug sequences in order to tailor treatment to each patient. This approach could permit selection of patients who could benefit most from a specific type of chemotherapy by matching their tumor and individual genetic profile. Nevertheless, this potential has been limited so far by reliance on the single biomarker approach, though this is now on the way to being overcome through whole genome studies.

The Efficacy and Safety of Platinum/Vinorelbine as More Than Second-Line Chemotherapy for Advanced Non-small Cell Lung Cancer

PURPOSE

There is no regimen that is strongly recommended for more than second-line treatment. We investigated the efficacy and safety of platinum/vinorelbine as more than second-line treatment.

MATERIALS AND METHODS

We selected patients with advanced non-small cell lung cancer (NSCLC) who received treatment with platinum/vinorelbine at Chungnam National University Hospital from August 2001 to December 2013. The primary end point was the response rate, and secondary end points were progression-free survival (PFS), overall survival (OS), and toxicity.

RESULTS

Thirty-five patients were enrolled. Response rate was 22.9% (complete response, 0 patients [0%]; partial response, eight patients [22.9%]; stable disease, 10 patients [28.6%]; progressive disease, 14 patients [40.0%]). A significantly higher response rate was observed for patients who had responded to previous chemotherapy than for those who did not (34.8% [8/23] vs. 0% [0/12], p=0.020). The median PFS was 4 months (range, 1 to 21 months). Patients with adenocarcinoma and non-smokers had a significantly longer PFS than patients with non-adenocarcinoma and smokers (5 months vs. 2 months, p=0.007; 4.5 months vs. 2 months, p=0.046, respectively). The median OS was 10 months (range, 1 to 41 months). Patients with good performance status and non-smokers had a significantly longer OS than patients with poor performance status and smokers (14 months vs. 4 months, p=0.02; 18.5 months vs. 6 months, p=0.049, respectively). The main serious adverse event (grade 3 or 4) was neutropenia (15 events, 13.3%) in a total of 113 cycles.

CONCLUSION

Platinum/vinorelbine was effective as more than second-line chemotherapy, and the toxicity was tolerable, in patients with advanced NSCLC.

The Effectiveness of Pemetrexed Monotherapy Depending on Polymorphisms in TS and MTHFR Genes as Well as Clinical Factors in Advanced NSCLC Patients

In NSCLC, second-line chemotherapy using pemetrexed or docetaxel has limited efficacy and should be dedicated to selected groups of patients. Pemetrexed is an antifolate compound with the ability to inhibit enzymes (TS, DHFR and GARFT) involved in pyrimidine and purine synthesis. The objective of this study was to evaluate the association between polymorphisms of TS and MHFR genes and clinical outcomes in NSCLC patients treated with pemetrexed monotherapy. DNA was isolated from peripheral blood of 72 non-squamous NSCLC patients treated with pemetrexed. Using PCR and RFLP methods, the variable number of tandem repeats (VNTR), the G > C SNP in these repeats and insertion/deletion polymorphism of TS gene as well as 677C > T SNP in MTHFR gene were analyzed and correlated with disease control rate, progression-free survival and overall survival (OS) of NSCLC patients. Carriers of 2R/3R(G), 3R(C)/3R(G), 3R(G)/3R(G) genotypes showed significantly more frequent early progression than carriers of 2R/2R, 2R/3R(C), 3R(C)/3R(C) genotypes of TS gene (p < 0.05). Among carriers of triple 28 bp tandem repeats (3R) in TS gene and C/C genotype of MTHFR gene a significantly shorter OS was observed (HR = 3.07; p = 0.003). In multivariate analysis, significantly higher risk of death was observed in carriers of both 3R/3R genotype in TS and C/C genotype in 677C > T SNP in MTHFR (HR = 3.85; p < 0.005) as well as in patients with short duration of response to first-line chemotherapy (HR = 2.09; p < 0.005). Results of our study suggested that genetic factors may have a high predictive and prognostic value (even greater than clinical factors) for patients treated with pemetrexed monotherapy.

Third- and further-line therapy in advanced non-small-cell lung cancer patients: an overview

Non-small-cell lung cancer (NSCLC) treatment has led to improved efficacy and compliance due to individual tailoring of the therapeutic options and the use of strategies based on both clinical characteristics and histological and biological features of the disease. In nonsquamous NSCLC, novel agents, such as pemetrexed and bevacizumab, have improved survival in the first-line setting. Maintenance therapy with pemetrexed and erlotinib resulted in improved progression-free survival compared with second-line therapy at disease progression. In the second-line setting, pemetrexed improves survival in nonsquamous NSCLC compared with docetaxel, and erlotinib has shown a survival benefit compared with best supportive care in patients who did not previously receive an EGF receptor inhibitor. Although the benefit of first- and second-line treatment over best supportive care alone has been firmly established, the role of further-line treatment remains controversial. This article summarizes the state-of-the-art treatments in this setting.

Efficacy of fourth-line chemotherapy in advanced non-small-cell lung cancer: a systematic review and pooled analysis of published studies

There are no agents labelled for use as fourth-line therapy for non-small-cell lung cancer, even though it is currently prescribed in about 5-10% of patients. Here, we provide a pooled analysis of published studies on the efficacy of treatments in patients who have had at least three unsuccessful lines of therapy. The literature search was performed on Pubmed, EMBASE, the Web of Science, SCOPUS, CINAHL, Google Scholar and the Cochrane Library using the terms 'lung cancer' OR NSCLC AND 'fourth line'. The response rates and disease control rates were pooled using a random-effect or a fixed-effect model according to heterogeneity. Median progression-free survival and overall survival data were also collected and aggregated to obtain pooled median values of the included studies. Overall, 14 studies (673 patients), which were almost entirely published by Asian institutions, were eligible for this pooled analysis. Among these were two phase II trials and 12 retrospective cohort series. In general, the pooled overall response rate was 13.6% [95% confidence interval (CI) 10-18.3] and the pooled overall disease control rate was 47.3% (95% CI 38-56.9). The pooled median progression-free survival for these studies was 3.34 months (95% CI 2.42-4.27). The pooled median overall survival for these studies was 10.5 months (95% CI 9.57-11.52). In conclusion, for non-small-cell lung cancer patients who have undergone three or more unsuccessful lines of therapy, fourth-line treatment could be offered in select cases to those with a good performance status.

[Fourth-line and beyond therapy in advanced non-small cell lung cancer: a retrospective analysis]

背景与目的

晚期非小细胞肺癌的一、二线治疗策略已达成广泛共识，对于三线治疗，最新的美国国立综合癌症网络（National Comprehensive Cancer Network, NCCN）指南中已有相关推荐。本研究旨在研究晚期非小细胞肺癌四线及以上治疗结果及影响因素。

方法

回顾性分析我院肿瘤中心四线及以上治疗的140例晚期非小细胞肺癌患者的临床资料，对其有效率、生存及预后因素等进行分析。

结果

18例（12.9%）部分缓解（partial response, PR)，36例（25.7%）疾病稳定（stable disease, SD），疾病控制率（disease control rate, DCR）为38.6%。中位总生存时间（overall survival, OS）及四线治疗后OS分别为31个月及10.1个月。四线治疗中位无疾病进展生存时间（progression free survival, PFS）为2.6个月。单因素及多因素分析均显示不同治疗选择及是否后续治疗是四线OS独立预后因素。未发现四线PFS的独立预后因素。化疗组较靶向组四线中位OS更长（11.7个月vs 7.1个月，P=0.013）。单药及双药化疗，首次及反复使用表皮生长因子受体络氨酸激酶抑制剂（epidermal growth factor receptor tyrosine kinase inhibitor, EGFR-TKI）四线中位OS无差异。

结论

对有条件接受四线治疗的晚期非小细胞肺癌患者，接受四线治疗能获得生存的延长。四线治疗在晚期非小细胞肺癌的地位值得前瞻性临床试验进一步探讨。

Is fourth-line chemotherapy routine practice in advanced non-small cell lung cancer?

BACKGROUND

Despite advances in palliative chemotherapy, patients with advanced non-small cell lung cancer (NSCLC) eventually experience disease progression during or after completion of first-line chemotherapy, which requires salvage therapy. Second- or third-line therapy in selected patients is recommended in the current guidelines. Although fourth-line therapy is often performed in daily practice in some countries, there are few reports about the clinical benefits of fourth-line therapy.

PATIENTS AND METHODS

A retrospective review was conducted on 383 patients who underwent at least first-line palliative chemotherapy for advanced NSCLC (stage IV or stage IIIB/recurrent disease unsuitable for definitive local therapy). Overall survival (OS) and clinicopathological characteristics were analyzed according to the lines of chemotherapy as well as for all study patients.

RESULTS

The median OS for all patients after the initiation of first-line therapy was 11 months. The median OS for patients who received fourth- or further-line therapy (77 patients) was longer than that of patients who received third- or lesser-line therapy (27 versus 9 months, p<0.0001). In multivariate analysis, fourth- or further-line therapy was independently associated with favorable OS (hazard ratio: 0.44, 95% confidence interval: 0.34-0.57, p<0.0001) along with recurrent disease, female, age <70 years, and ECOG performance status (PS) 0 or 1. Median OS after the start of fourth-line therapy was 9 months. Good PS (ECOG PS 0, 1) at the initiation of fourth-line therapy (10 versus 2 months, p<0.0001) and disease control (10 versus 7 months, p=0.011) after first-line therapy were associated with favorable OS in univariate analysis, while poor PS (ECOG PS ≥2) was an independent prognostic factor for poor outcome (p<0.0001).

CONCLUSION

The present study suggests that advanced NSCLC patients with good PS after progression from third-line therapy could be considered as reasonable candidates for fourth-line therapy in clinical practice.

Associations between TS, TTF-1, FR-α, FPGS, and overall survival in patients with advanced non-small-cell lung cancer receiving pemetrexed plus carboplatin or gemcitabine plus carboplatin as first-line chemotherapy

INTRODUCTION

Pemetrexed is effective in the treatment of non-small-cell lung cancer, mainly in nonsquamous cell carcinomas. Inhibition of thymidylate synthase (TS) is considered the key mechanism of action. Folate receptor-α facilitates uptake of pemetrexed. Polyglutamation by folylpolyglutamate synthetase enhances activity and prolongs cellular retention of pemetrexed. Thyroid transcription factor-1 (TTF-1) is mainly positive in nonsquamous cell carcinoma and has been proposed as a marker for sensitivity to pemetrexed. The aim was to investigate associations between these biomarkers and survival in patients who participated in a phase III trial comparing pemetrexed plus carboplatin with gemcitabine plus carboplatin as first-line chemotherapy in advanced non-small-cell lung cancer (n = 436). In this study, there was no difference in overall survival between the two regimens.

METHODS

Formalin-fixed, paraffin-embedded biopsies were collected. Percentages of tumor cells positive and highly positive for the biomarkers were assessed using immunohistochemistry (IHC) and an IHC score was calculated (range, 0-200).

RESULTS

Two hundred thirty-six biopsies were analyzed (pemetrexed plus carboplatin: n = 114, gemcitabine plus carboplatin: n = 122). There was a significant difference in overall survival between those with TTF-1-positive and -negative tumors (10.4 versus 6.0 months; p < 0.001) and those with a low and a high TS IHC score (9.7 versus 6.2 months; p < 0.001). Folate receptor-α and folylpolyglutamate synthetase were not significant prognostic factors. In multivariate analyses adjusting for established prognostic characteristics, TS (p = 0.002) and TTF-1 (p = 0.003) remained significant. There were no differences in survival between the treatment arms depending on biomarker scores.

CONCLUSIONS

TTF-1 positivity and low TS level were associated with prolonged survival. The associations between the biomarkers and overall survival were similar for both chemotherapy regimens.

The pemetrexed-containing treatments in the non-small cell lung cancer is -/low thymidylate synthase expression better than +/high thymidylate synthase expression: a meta-analysis

BACKGROUND

The predictive value of thymidylate synthase (TS) for clinical sensitivity to pemetrexed-containing chemotherapy in patients with non-small cell lung cancer (NSCLC) remains controversial. This meta-analysis is performed to provide an assessment of whether expression variations of TS are associated with objective response in patients with NSCLC treated with pemetrexed-containing chemotherapy.

METHODS

An electronic search was conducted using the databases MEDLINE, EMBASE and CNKI, from inception to June 10th, 2013. A systemic review of the studies on the association between TS expression in NSCLC and objective response of pemetrexed-containing regimen was performed. Pooled odds ratios (OR) for the response rate were calculated using the software Revman 5.0.

RESULTS

There were a total of 526 patients in the eight studies that met our criteria for evaluation. +/high expression of TS was found in 269 patients (51.1%), and -/low expression for this gene was found in 257 (48.9%) patients. The objective response rate for pemetrexed-containing chemotherapy was significantly higher in patients with -/low expression TS expression (OR = 0.45; 95% CI, 0.29-0.70; p = 0.0004). Although patients with -/low expression of TS have a longer median overall survival time and progression free survival time than those with +/high expression of TS, the difference was not statistically significant.

CONCLUSIONS

-/low expression of TS was associated with higher objective response in NSCLC patients treated with pemetrexed-containing chemotherapy. TS may be a suitable marker of sensitivity to pemetrexed-based chemotherapy in patients with NSCLC.

Thymidylate synthase protein expression levels remain stable during paclitaxel and carboplatin treatment in non-small cell lung cancer

BACKGROUND

Thymidylate synthase (TS) is a potential predictive marker for efficacy of treatment with pemetrexed. The current study aimed at investigating whether TS expression changes during non-pemetrexed chemotherapy of non-small cell lung cancer (NSCLC), thus making rebiopsy necessary for deciding on pemetrexed second-line treatment.

MATERIALS AND METHODS

TS immunohistochemístry was performed on biopsies and available resection specimens from 65 NSCLC patients stage T1-3N0-2 treated with preoperative carboplatin and paclitaxel [neoadjuvant chemotherapy (NAC)-group] and from 53 NSCLC patients stage T1-4N0-1 treated with surgery without preceding chemotherapy [operation (OP)-group] that served as controls. The diagnostic biopsies and subsequent resection samples were compared in order to evaluate for change in TS expression in groups treated with and without preoperative chemotherapy.

RESULTS

No statistically significant change in TS expression was observed between diagnostic biopsies and subsequent surgical resections of primary tumors in either the OP-group (p = 0.186) or the NAC-group (p = 0.542). Primary tumors were discordant between diagnostic biopsies and resection specimens when TS expression was dichotomized into high (H score ≥ 150) and low (H score < 150), in 45 and 33% in the OP-group and NAC-group, respectively (p = 0.288). The fraction of tumors which increased (19 vs. 20%; p = 0.900) and decreased (42 vs. 23%; p = 0.095) in TS expression was equal between the OP- and the NAC-group.

CONCLUSION

The discordance observed between paired serial samples likely reflects intratumoral heterogeneity of TS expression and highlights the need of sufficient representative material for TS expression analysis if this biomarker is to be used for treatment selection. TS expression in primary tumors remained unchanged, and new biopsies for deciding on second-line pemetrexed does not seem warranted based on the current results.

Thymidylate Synthase as a Predictive Biomarker for Pemetrexed Response in NSCLC

In recent years, major strides in cancer research have made it possible to select personalized chemotherapy recommendations based on an individual patient's tumor biology. The prognostic and/or predictive ability of biomarkers seeks to tailor the use of targeted chemotherapy and can result in improved clinical outcomes with reduced toxicity. A proliferation of new technology and pharmacotherapeutics in the setting of current FDA Clinical Laboratory Improvement Amendment (CLIA) standards has resulted in a recent surge in direct-to-physician biomarker tests. However, in the absence of clinical validation, there is the concern that the biomarkers may be utilized prematurely, resulting in improper chemotherapy selection and patient harm. Thymidylate synthase (TS) has been marketed as a predictive biomarker for the use of pemetrexed in NSCLC. We will examine the evidence behind the use of TS as a predictive biomarker to predict response to pemetrexed in NSCLC. At this time, the evidence does not currently support using TS assays to guide chemotherapy selection outside of a clinical research protocol.

Expression of thymidylate synthase predicts clinical outcomes of pemetrexed-containing chemotherapy for non-small-cell lung cancer: a systemic review and meta-analysis

PURPOSE

Observational and preclinical studies suggested an association between the expression of thymidylate synthase (TS) and clinical effects of pemetrexed-based chemotherapy in non-small-cell lung cancer (NSCLC) patients. However, the predictive value of TS for pemetrexed-containing chemotherapy regimen remained controversial. The aim of the study was to further appraise the association between the expression of TS and clinical efficacy pemetrexed-based chemotherapy in NSCLC patients.

METHODS

We searched in MEDLINE (PubMed), EMBASE, and Cochrane Library from January 1945 to May 2013. Two authors independently extracted information from the characteristics of study participants. Primary outcomes included therapeutic response (TR; i.e., complete response + partial response vs. stable disease + progressive disease), progression-free survival (PFS), and overall survival (OS). Relative risk (RR) and hazard ratio (HR) were used for evaluating the risk or hazard.

RESULTS

Eight studies were included in the meta-analysis. Better response usually appeared in NSCLC patients with a lower expression of TS [RR = 2.06 95 % confidence intervals (CI) 1.44, 2.96]. There was a significant association between TS expression and outcomes of pemetrexed-based chemotherapy for NSCLC (PFS: HR = 0.63 95 % CI 0.52, 0.76; OS: HR = 0.74, 95 % CI: 0.63, 0.88). In addition, no evidence of publication bias was observed.

CONCLUSIONS

This meta-analysis evaluated the predictive value of TS and provided evidence that NSCLC patients with lower TS expression could significantly benefit from pemetrexed-based chemotherapy. This increased level of TS was probably an independent risk factor of potential resistance against pemetrexed.

A phase II study of pemetrexed in patients with previously heavily treated non-squamous non-small cell lung cancer (HANSHIN Oncology Group 001)

PURPOSE

Pemetrexed has shown substantial activity in non-squamous non-small cell lung cancer (NSCLC) and is one of the current standard agents in second-line settings due to its efficacy and favorable tolerability profile. We conducted phase II study to evaluate the safety and efficacy of pemetrexed in Japanese patients with previously heavily treated, advanced non-squamous NSCLC.

METHODS

Patients with stage IIIB or IV non-squamous NSCLC, performance status (PS) 0-2, previous two to five regimens of chemotherapy were enrolled and received pemetrexed (500 mg/m(2)) on day 1 every 21 days until disease progression. The primary endpoint was progression-free survival (PFS). The secondary endpoints included overall survival (OS), objective response rate (ORR), disease control rate (DCR), and safety.

RESULTS

From August 2009 to May 2010, 46 patients were enrolled: median age 65 years; 52 % women; PS 0/1/2 26/67/7 %; previous treatment regimen 2/3/4/5 48/28/20/4 %; epidermal growth factor receptor activating mutation positive/wild/unknown 30/48/22 %. The median follow-up period was 13.5 months. The median number of treatment cycles was 4 (range 1-18 cycles). The median PFS was 5.2 months (95 % CI 3.0-5.8 months). The median OS was 14.4 months (95 % CI 9.4-21.3 months). The ORR was 8.7 % and DCR was 63.0 %. The grade 3/4 hematological adverse events include 8 patients with leukopenia, 11 with neutropenia, 5 with anemia, and 2 with thrombocytopenia. There were no reports of febrile neutropenia and no treatment-related death was observed.

CONCLUSION

Treatment with pemetrexed in previously heavily treated Japanese non-squamous NSCLC patients is feasible and shows encouraging activity.

[Efficacy of chemotherapy after EGFR-TKIs resistance in 191 patients with Unknow EGFR gene mutation in advanced lung adenocarcinoma]

背景与目的

晚期肺腺癌患者在使用表皮生长因子受体酪氨酸激酶抑制剂（epidermal growth factor receptor tyrosine kinase inhibitors, EGFR-TKIs）治疗进展后需要接受化疗。本研究旨在探讨EGFR-TKIs耐药后进行化疗的疗效影响因素。

方法

回顾性分析191例晚期肺腺癌患者的临床特征、EGFR-TKIs耐药后第一次化疗的近期疗效及生存时间。

结果

含培美曲塞方案的有效率明显高于不含培美曲塞组，客观缓解率（objective response rate, ORR）分别为9.3%和1.1%（P=0.011），以二线化疗更为明显，ORR分别为14.3%和3.7%（P=0.041）。化疗最好疗效达部分缓解（partial response, PR）者的无进展生存期（progression-free survival, PFS）明显长于未达到PR者（PFS分别为10.1个月和2.3个月，P=0.012）；含铂方案的PFS及总生存期（overall survival, OS）均长于不含铂方案，是独立的预后因素[PFS：相对风险（relative risk, RR）=0.634，95%CI：0.466-0.832，P=0.004；OS：RR=0.666，95%CI：0.460-0.960，P=0.030]，其中TKIs获得性耐药的患者和爆发式进展的患者进行含铂化疗生存获益更多。TKIs耐药的性质（原发或获得性）及TKIs耐药模式（爆发进展、缓慢进展和局部进展）对后续化疗的ORR、PFS及OS均无明显影响。

结论

对于EGFR-TKIs耐药的晚期肺腺癌患者，含培美曲塞方案和含铂方案可能疗效较好。

Association between TYMS expression and efficacy of pemetrexed-based chemotherapy in advanced non-small cell lung cancer: a meta-analysis

Background

The predictive value of thymidylate synthase (TYMS) to sensitivity to pemetrexed-based chemotherapy in advanced non-small cell lung cancer (NSCLC) patients is controversial. We conducted a meta-analysis of all relevant published data to assess the association of TYMS expression with the clinical outcomes of pemetrexed-based regimen in advanced NSCLC.

Patients and Methods

We conducted an electronic search using using PubMed, Embase, OVID and Cochrane Library databases and manual search. Pooled odds ratio (OR) for the response rate and hazard ratio (HR) for the overall survival and progression free survival were calculated using the software Revman 5.0.

Results

There were 11 studies (n=798) met our criteria for evaluation. Response rate to pemetrexed-based regimen was significantly higher in patients with low/negative TYMS (OR=2.96, 95%CI [1.81, 4.86] P<0.0001). Patients with low/negative TYMS who were treated with pemetrexed-based regimen had longer progression free survival (HR 0.50, 95%CI [0.41, 0.61] P <0.00001) and overall survival (HR 0.41, 95%CI [0.22, 0.78] P=0.007) than those with high/positive TYMS.

Conclusions

Low/negative TYMS expression was significantly associated with higher response rate, longer median survival and longer progression free survival for advanced NSCLC patients receiving pemtrexed-based chemotherapy. Hence, TYMS may be a potential predictor of sensitivity to pemtrexed-based chemotherapy in advanced NSCLC. Large scale prospective clinical trials are still warranted.

Uracil-DNA glycosylase expression determines human lung cancer cell sensitivity to pemetrexed

Uracil misincorporation into DNA is a consequence of pemetrexed inhibition of thymidylate synthase. The base excision repair (BER) enzyme uracil-DNA glycosylase (UNG) is the major glycosylase responsible for removal of misincorporated uracil. We previously illustrated hypersensitivity to pemetrexed in UNG(-/-) human colon cancer cells. Here, we examined the relationship between UNG expression and pemetrexed sensitivity in human lung cancer. We observed a spectrum of UNG expression in human lung cancer cells. Higher levels of UNG are associated with pemetrexed resistance and are present in cell lines derived from pemetrexed-resistant histologic subtypes (small cell and squamous cell carcinoma). Acute pemetrexed exposure induces UNG protein and mRNA, consistent with upregulation of uracil-DNA repair machinery. Chronic exposure of H1299 adenocarcinoma cells to increasing pemetrexed concentrations established drug-resistant sublines. Significant induction of UNG protein confirmed upregulation of BER as a feature of acquired pemetrexed resistance. Cotreatment with the BER inhibitor methoxyamine overrides pemetrexed resistance in chronically exposed cells, underscoring the use of BER-directed therapeutics to offset acquired drug resistance. Expression of UNG-directed siRNA and shRNA enhanced sensitivity in A549 and H1975 cells, and in drug-resistant sublines, confirming that UNG upregulation is protective. In human lung cancer, UNG deficiency is associated with pemetrexed-induced retention of uracil in DNA that destabilizes DNA replication forks resulting in DNA double-strand breaks and cell death. Thus, in experimental models, UNG is a critical mediator of pemetrexed sensitivity that warrants evaluation to determine clinical value.

Significance of folate receptor alpha and thymidylate synthase protein expression in patients with non-small-cell lung cancer treated with pemetrexed

INTRODUCTION

Folate receptor alpha (FRA) regulates cellular uptake of folates and antifolates. Information about FRA protein expression in metastatic non-small-cell lung cancer (NSCLC) is limited. We investigated FRA as a biomarker for pemetrexed-based chemotherapy and compared it with thymidylate synthase (TS), the main target of pemetrexed.

METHODS

Pretreatment tumor specimens from 207 patients with advanced NSCLC were assessed for FRA and TS protein expression by immunohistochemistry using the H-score (range, 0-300) and correlated to patients' clinicopathological data, radiographic response, progression-free survival (PFS), and overall survival (OS).

RESULTS

Low total (cytoplasmic and nuclear) TS protein expression (H-score < 210) was associated with improved PFS (median: 5.6 versus 3.5 months; hazard ratio [HR] = 0.6379, p = 0.0131) and prolonged OS (median: 22.5 versus 11.5 months; HR = 0.5680,p = 0.0107). An association between lower TS levels and response to pemetrexed-based therapy was found-mean H-score 187 ± 5, median 180 for responders versus mean H-score 201 ± 4, median 210, for non-responders, p = 0.0244. High intracellular FRA expression (H-score ≥110) was associated with prolonged OS (28.9 versus 11.7 months, HR = 0.5316, p = 0.0040) and a trend for association with PFS (5.6 versus 4.1 months, HR = 0.7395, p = 0.0801) was noted. Membranous FRA expression was seen in 83% of patients, moreover, high membranous expression (H-score ≥20) was associated with improved PFS (5.6 versus 3.7 months, HR = 0.6445, p = 0.0306) and OS (22.1 versus 11.5 months, HR = 0.5378, p = 0.0131).

CONCLUSIONS

A large number of NSCLC patients have high expression of FRA and/or a low level of TS expression. Expression levels of FRA and TS were associated with clinical benefit from pemetrexed therapy.

Thymidylate synthase and ERCC1 as predictive markers in patients with pulmonary adenocarcinoma treated with pemetrexed and cisplatin

Increased expression of thymidylate synthase (TS) is thought to be associated with resistance to antifolate drugs such as pemetrexed. Excision repair cross-complementation group 1 (ERCC1) is a predictive marker for platinum-based chemotherapy. This study evaluated whether the expression of TS and ERCC1 proteins is associated with clinical outcomes of the patients with pulmonary adenocarcinoma who were treated with pemetrexed/cisplatin as first-line chemotherapy. The expressions of TS and ERCC1 were evaluated by immunohistochemistry in biopsy specimens obtained from patients with pulmonary adenocarcinoma who had received pemetrexed/cisplatin as first-line treatment. Patients were categorized according to median H-score. Response rate (RR), progression-free survival (PFS) and overall survival (OS) were analyzed retrospectively. Both low TS and ERCC1 expressions were significantly associated with better RR (p = 0.037 and p = 0.015, respectively) and longer PFS (p < 0.001 and p = 0.004, respectively). Low ERCC1 expression was also associated with longer OS (p = 0.003) while TS only showed a trend (p = 0.105). TS expression was independent predictor for the better PFS in multivariate analysis (hazard ratio [HR] = 0.32, 95% confidence interval [CI]: 0.14-0.76). Combining the two markers, the low TS/low ERCC1 group showed significantly longer PFS (HR = 0.48, 95% CI: 0.26-0.75) and OS (HR = 0.57, 95% CI: 0.36-0.89) compared with high TS/high ERCC1 group. Protein expressions of TS and ERCC1 were associated with clinical outcomes in patients with pulmonary adenocarcinoma who were treated with pemetrexed/cisplatin as first-line chemotherapy. TS and ERCC1 protein expressions can be potential predictive markers in this setting.

Bevacizumab and weekly paclitaxel for non-squamous non small cell lung cancer patients: a retrospective study

BACKGROUND

Combination of bevacizumab and weekly paclitaxel showed synergitic effects, anti-tumor efficacy and a good toxicity profile for patients with breast cancer but has never been evaluated in non small cell lung cancer (NSCLC). We retrospectively reviewed safety and efficacy of this regimen in metastatic non-squamous NSCLC as fourth-line therapy or beyond.

METHODS

Patients were identified from a prospective database. Treatment consisted in paclitaxel 80 mg/m(2) on days 1, 8 and 15 and bevacizumab 15 mg/kg on day 1, every 3 weeks until progression or unacceptable toxicity.

RESULTS

Twenty patients were included in this study. Objective response rate at first evaluation was 40% (8/20), confirmed response rate was 15% (3/20) and disease control rate was 75% (15/20). The median progression-free survival and overall survival were 6.4 months (CI95% 4.1-9) and 9.6 months (CI95% 7-19.7). Grade 3-4 adverse events included neutropenia (4/20), onycholysis (2/20) and infection (2/20). One patient died from a bowel perforation and another one died from unknown cause. Prolonged responses were observed in a patient who had received bevacizumab as part of first-line chemotherapy and in another one who harbored an ALK rearrangement.

CONCLUSIONS

In our experience, combination of bevacizumab and weekly paclitaxel exhibited acceptable toxicity and had encouraging anti-tumor efficacy as fourth-line treatment or beyond for non-squamous NSCLC patients, supporting further evaluation in larger prospective studies.

Thymidylate synthase expression and molecular alterations in adenosquamous carcinoma of the lung

Thymidylate synthase expression is known to be higher in squamous cell carcinoma than in adenocarcinoma of the lung. It is thought that this is the reason for the poor efficacy of pemetrexed in squamous cell carcinoma. However, there is limited data on thymidylate synthase expression in adenosquamous carcinoma, a distinct subtype of lung cancer containing both squamous and glandular differentiation. Furthermore, molecular alterations like epidermal growth factor receptor and Kirsten rat sarcoma 2 viral oncogene homolog mutations, which are seen in adenocarcinomas, are not well understood in mixed histology tumors such as adenosquamous carcinoma. In our study, we sought to better characterize adenosquamous tumors of the lung. Using immunohistochemistry to evaluate thymidylate synthase protein levels, we found that the expression of thymidylate synthase in these mixed tumors roughly parallel that of squamous cell carcinoma, instead of falling in between squamous cell and adenocarcinoma. Of note, in adenosquamous samples, the expression of thymidylate synthase was more closely correlated within the two components than would be expected by random chance alone. Also, we had a relatively high rate of epidermal growth factor receptor (11%) and Kirsten rat sarcoma 2 viral oncogene homolog (33%) mutations in these specimens, with the mutations showing convergence in both the glandular and squamous components upon microdissection. Our results indicate that adenosquamous carcinomas are not simple mixtures of their two histological components; they rather behave as their own entity, and it is important to further understand their behavior. Given the similarity of thymidylate synthase expression between squamous cell and adenosquamous carcinoma, and that thymidylate synthase is the main target of pemetrexed, we extrapolate that pemetrexed may also have inferior clinical activity in adenosquamous carcinoma.

Association of thymidylate synthase gene 3'-untranslated region polymorphism with sensitivity of non-small cell lung cancer to pemetrexed treatment: TS gene polymorphism and pemetrexed sensitivity in NSCLC

Background

Thymidylate synthase (TS) is a key enzyme responsible for DNA synthesis and repair. Altered expression of TS protein or TS gene polymorphisms has been associated with cancer progression and treatment response. This study investigated the expressions of TS and its gene SNPs in non-small cell lung cancer (NSCLC), and then its association with sensitivity to pemetrexed treatment. Immunohistochemistry and qRT-PCR were performed on 160 resected NSCLC specimens and corresponding normal tissues to assess the expressions of TS protein and TS mRNA, and for associations with clinicopathological data. Blood samples of 106 lung adenocarcinoma patients were examined for polymorphisms of the TS gene 3’-UTR 1494del 6 bp, which was then investigated for associations with responses of the patients to pemetrexed treatment and survival.

Results

Expression of both TS protein and its mRNA was elevated in NSCLC tissues compared with matched normal tissues, and significantly higher in lung squamous cell carcinoma than in lung adenocarcinoma. TS expression was associated with poor tumor differentiation. Furthermore, the genotyping data showed that 56% of lung adenocarcinoma patients had the TS gene 3’-UTR 1494 bp (−6 bp/-6 bp) genotype and the rest had TS gene 3’-UTR 1494 bp (−6 bp/+6 bp). There was no TS 3’-UTR 1494 bp (+6 bp/+6 bp) genotype in any patients. Statistical analysis revealed that gender, tumor stage, and TS 3’-UTR 1494del 6 bp polymorphism were significant prognostic factors after short-term pemetrexed treatment. Log-rank analysis revealed that patients with the (−6 bp/-6 bp) genotype had significantly better progression-free and overall survival than patients with (−6 bp/+6 bp).

Conclusions

This study showed that TS protein is highly expressed in NSCLC and that polymorphisms of TS 3’-UTR 1494del 6 bp are associated with sensitivity of lung adenocarcinoma patients to pemetrexed treatment. This suggests that TS gene polymorphisms should be further evaluated as prognostic markers for personalized therapy in lung adenocarcinoma.

[Efficacy of pemetrexed as second-line therapy or beyond in patients with advanced non-small cell lung cancer]

BACKGROUND AND OBJECTIVE

Pemetrexed is a standard second-line therapy in advanced non-small cell lung cancer (NSCLC). Currently, cytotoxic treatments beyond second-line therapy are not available. This study evaluated the efficacy and safety of pemetrexed as a salvage regimen in heavily pretreated patients with NSCLC.

METHODS

Clinical data on 37 patients with advanced NSCLC who received pemetrexed as second-line therapy or beyond in Cancer Hospital of Peking Union Medical College from Feb 2005 to Sep 2009 were reviewed and analyzed retrospectively.

RESULTS

Thirteen patients (35.1%) received pemetrexed as second-line treatment, whereas 24 (64.9%) received it as third-line treatment or beyond. Complete response, partial response, stable disease and progressive disease were noted in 1 (2.7%), 2 (5.4%), 17 (45.9%) and 12 (32.4%) of the patients, respectively, with the disease control rate being 54.1%. The median duration of progression free survival was 8.05 months, whereas that of overall survival was 19.29 months.

CONCLUSIONS

Pemetrexed is efficacious and tolerable as second-line therapy or beyond for advanced NSCLC and should thus be recommended for patients with this disease.

Biomarker analysis in a phase III study of pemetrexed-carboplatin versus etoposide-carboplatin in chemonaive patients with extensive-stage small-cell lung cancer

BACKGROUND

Clinical results of a randomized phase III trial comparing pemetrexed-carboplatin (PC) with etoposide-carboplatin (EC) in chemonaive patients with extensive-stage disease small-cell lung cancer (ED-SCLC) resulted in trial closure for futility; biomarker analyses using immunohistochemistry (IHC) and single-nucleotide polymorphisms (SNPs) are described herein.

PATIENTS AND METHODS

Thymidylate synthase (TS), excision repair cross complementing-1 (ERCC1), glycinamide ribonucleotide formyltransferase (GARFT), and folylpolyglutamate synthetase (FPGS) were investigated using IHC (n=395). SNPs were genotyped for TS, FPGS, γ-glutamyl hydrolase (GGH), methylenetetrahydrofolate reductase (MTHFR), folate receptor-α FR-α, and solute carrier 19A1 (SLC19A1; n=611).

RESULTS

None of the IHC biomarkers (folate pathway or ERCC1) were found to be predictive or prognostic in this setting. rs2838952 (adjacent to SLC19A1) had significant treatment-independent association with overall survival (OS; hazard ratio 0.590, P=0.01). Nine GGH-associated SNPs interacted with rs3788205 (SLC19A1) for OS on the PC arm. rs12379987 (FPGS) interacted with treatment for OS (interaction P=0.036).

CONCLUSION

Potential ERCC1 and folate pathway IHC biomarkers failed to predict outcome in either study arm in ED-SCLC. SNPs in regions including FPGS and SLC19A1 and interacting SNPs in GGH and SLC19A1 were associated with differences in OS; however, none of these SNPs predicted for greater survival with PC over EC.

[Pemetrexed alone versus pemetrexed combined with oxaliplatin as salvage therapy in stage IV lung adenocarcinoma]

背景与目的

目前肺癌挽救性治疗尚无标准方案。本研究旨在比较培美曲赛单药与培美曲赛联合奥沙利铂挽救性治疗Ⅳ期肺腺癌患者的疗效及安全性，为联合化疗提供依据。

方法

2009年1月-2011年2月共83例体能状态评分（performance status, PS）为0分-2分的Ⅳ期肺腺癌患者分别接受培美曲赛（单药组47例）和培美曲赛联合奥沙利铂（联合组36例）挽救性治疗，观察两组近期疗效和毒性反应并进行比较。

结果

81例患者纳入最终分析。单药组与联合组中位无进展生存时间（progression-free survival, PFS）分别为3.6个月vs 4.1个月（P=0.268），客观反应率（objective response rate, ORR）和疾病控制率（disease control rate, DCR）分别为6.5% vs 20%（P=0.092）和56.5% vs 65.7%（P=0.493）。单药组与联合组血液毒性及胃肠道反应发生率分别为33.9% vs 47.2%（P=0.460）和21.2% vs 25.0%（P=0.213）。

结论

培美曲赛联合奥沙利铂挽救性治疗PS评分较好的Ⅳ期肺腺癌患者耐受性良好，与培美曲赛单药相比显示出较高的缓解率，但未明显增加患者的PFS。

Retrospective analysis of third-line and fourth-line chemotherapy for advanced non-small-cell lung cancer

BACKGROUND

The efficacy of third-line and further-line chemotherapy for advanced non-small-cell lung cancer (NSCLC) remains unknown.

PATIENTS AND METHODS

We evaluated the clinical outcome of third- and fourth-line chemotherapy for the treatment of advanced NSCLC in consecutive patients who received first-line chemotherapy at our institute between July 2002 and June 2006. From a hospital-based registry, the following data were extracted: (a) patient characteristics, (b) type of chemotherapeutic agents, and (c) objective response and survival data.

RESULTS

A total of 599 patients were included in this analysis. Overall, 69.3%, 38.4%, 17.7%, and 6.0% of the patients received second-, third-, fourth-, and fifth-line chemotherapy, respectively. Significant differences in age (P < .0001), performance status at the start of first-line chemotherapy (P < .0001), and histology (P = .0175) were observed between patients who received third-line chemotherapy and those who did not. Docetaxel, gefitinib, and S-1 were the most frequently used regimens for third- or fourth-line chemotherapy. Five percent of the patients had participated in phase I trials of investigational new drugs. The objective response rates and disease control rates of third- and fourth-line chemotherapy were 17.0% and 34.4% and 11.3% and 24.5%, respectively. The median survival times (95% confidence interval [CI]) from the start of first-, second-, third-, and fourth-line chemotherapy until death were 15.3 months (95% CI, 13.8-16.5 months), 12.8 months (95% CI, 10.7-14.5 months), 12.0 months (95% CI, 9.3-14.2 months), and 9.9 months (95% CI, 8.6-12.0 months), respectively.

CONCLUSION

As many as 38% of patients with advanced NSCLC who received first-line chemotherapy could receive third-line chemotherapy. This result emphasizes the need for randomized controlled trials of third-line treatment in patients with advanced NSCLC.

Phase II study of erlotinib as third-line monotherapy in patients with advanced non-small-cell lung cancer without epidermal growth factor receptor mutations

OBJECTIVE

There are few standard therapeutic options beyond second-line treatment. We aimed to evaluate the efficacy and safety of erlotinib monotherapy as third-line chemotherapy in patients with advanced non-small-cell lung cancer without epidermal growth factor receptor mutations.

METHODS

In this phase II trial, patients who did not have epidermal growth factor receptor mutations and who had previously received two cytotoxic chemotherapy regimens containing platinum were treated with erlotinib (150 mg, per os) until disease progression or unacceptable toxicity.

RESULTS

Twenty patients were eligible for the assessment of efficacy and safety. Three cases showed a partial response, and eight cases showed stable disease with an overall response rate of 15.0% (95% confidence interval: 5.2-36.0%) and a disease control rate of 55.0% (95% confidence interval: 34.2-74.2%). Median progression-free survival and overall survival time were 2.1 and 6.7 months, respectively. Although dose reduction was required in one patient because of skin toxicity, grade 3/4 toxicity or pulmonary disease was not observed.

CONCLUSIONS

Erlotinib as third-line therapy showed an acceptable response rate, survival time and toxicity. It could be a potential third-line therapy for patients without epidermal growth factor receptor mutations.

International association for the study of lung cancer/american thoracic society/european respiratory society international multidisciplinary classification of lung adenocarcinoma

INTRODUCTION

Adenocarcinoma is the most common histologic type of lung cancer. To address advances in oncology, molecular biology, pathology, radiology, and surgery of lung adenocarcinoma, an international multidisciplinary classification was sponsored by the International Association for the Study of Lung Cancer, American Thoracic Society, and European Respiratory Society. This new adenocarcinoma classification is needed to provide uniform terminology and diagnostic criteria, especially for bronchioloalveolar carcinoma (BAC), the overall approach to small nonresection cancer specimens, and for multidisciplinary strategic management of tissue for molecular and immunohistochemical studies.

METHODS

An international core panel of experts representing all three societies was formed with oncologists/pulmonologists, pathologists, radiologists, molecular biologists, and thoracic surgeons. A systematic review was performed under the guidance of the American Thoracic Society Documents Development and Implementation Committee. The search strategy identified 11,368 citations of which 312 articles met specified eligibility criteria and were retrieved for full text review. A series of meetings were held to discuss the development of the new classification, to develop the recommendations, and to write the current document. Recommendations for key questions were graded by strength and quality of the evidence according to the Grades of Recommendation, Assessment, Development, and Evaluation approach.

RESULTS

The classification addresses both resection specimens, and small biopsies and cytology. The terms BAC and mixed subtype adenocarcinoma are no longer used. For resection specimens, new concepts are introduced such as adenocarcinoma in situ (AIS) and minimally invasive adenocarcinoma (MIA) for small solitary adenocarcinomas with either pure lepidic growth (AIS) or predominant lepidic growth with ≤ 5 mm invasion (MIA) to define patients who, if they undergo complete resection, will have 100% or near 100% disease-specific survival, respectively. AIS and MIA are usually nonmucinous but rarely may be mucinous. Invasive adenocarcinomas are classified by predominant pattern after using comprehensive histologic subtyping with lepidic (formerly most mixed subtype tumors with nonmucinous BAC), acinar, papillary, and solid patterns; micropapillary is added as a new histologic subtype. Variants include invasive mucinous adenocarcinoma (formerly mucinous BAC), colloid, fetal, and enteric adenocarcinoma. This classification provides guidance for small biopsies and cytology specimens, as approximately 70% of lung cancers are diagnosed in such samples. Non-small cell lung carcinomas (NSCLCs), in patients with advanced-stage disease, are to be classified into more specific types such as adenocarcinoma or squamous cell carcinoma, whenever possible for several reasons: (1) adenocarcinoma or NSCLC not otherwise specified should be tested for epidermal growth factor receptor (EGFR) mutations as the presence of these mutations is predictive of responsiveness to EGFR tyrosine kinase inhibitors, (2) adenocarcinoma histology is a strong predictor for improved outcome with pemetrexed therapy compared with squamous cell carcinoma, and (3) potential life-threatening hemorrhage may occur in patients with squamous cell carcinoma who receive bevacizumab. If the tumor cannot be classified based on light microscopy alone, special studies such as immunohistochemistry and/or mucin stains should be applied to classify the tumor further. Use of the term NSCLC not otherwise specified should be minimized.

CONCLUSIONS

This new classification strategy is based on a multidisciplinary approach to diagnosis of lung adenocarcinoma that incorporates clinical, molecular, radiologic, and surgical issues, but it is primarily based on histology. This classification is intended to support clinical practice, and research investigation and clinical trials. As EGFR mutation is a validated predictive marker for response and progression-free survival with EGFR tyrosine kinase inhibitors in advanced lung adenocarcinoma, we recommend that patients with advanced adenocarcinomas be tested for EGFR mutation. This has implications for strategic management of tissue, particularly for small biopsies and cytology samples, to maximize high-quality tissue available for molecular studies. Potential impact for tumor, node, and metastasis staging include adjustment of the size T factor according to only the invasive component (1) pathologically in invasive tumors with lepidic areas or (2) radiologically by measuring the solid component of part-solid nodules.

Pemetrexed in heavily pretreated non-small-cell lung cancer patients: case report and review of the literature

To date, there is no standard treatment for patients with metastatic non-small-cell lung cancer after multiple previous lines of chemotherapy. Pemetrexed in combination with cisplatin or as a single agent demonstrated significant activity in patients with nonsquamous non-small-cell lung cancer with a good toxicity profile. In this article, we present a case of pulmonary adenocarcinoma treated with pemetrexed after five lines of treatment, including the cytotoxic agents cisplatin plus vinorelbine, docetaxel, gemcitabine and the tyrosine kinase inhibitor erlotinib. We also review the role of pemetrexed in this setting of patients.