Wnt/ß-Catenin Signaling and Resistance to Immune Checkpoint Inhibitors: From Non-Small-Cell Lung Cancer to Other Cancers.

Lung cancer is the leading cause of cancer-related deaths worldwide. The standard of care for advanced non-small-cell lung cancer (NSCLC) without driver-gene mutations is a combination of an anti-PD-1/PD-L1 antibody and chemotherapy, or an anti-PD-1/PD-L1 antibody and an anti-CTLA-4 antibody with or without chemotherapy. Although there were fewer cases of disease progression in the early stages of combination treatment than with anti-PD-1/PD-L1 antibodies alone, only approximately half of the patients had a long-term response. Therefore, it is necessary to elucidate the mechanisms of resistance to immune checkpoint inhibitors. Recent reports of such mechanisms include reduced cancer-cell immunogenicity, loss of major histocompatibility complex, dysfunctional tumor-intrinsic interferon-γ signaling, and oncogenic signaling leading to immunoediting. Among these, the Wnt/ß-catenin pathway is a notable potential mechanism of immune escape and resistance to immune checkpoint inhibitors. In this review, we will summarize findings on these resistance mechanisms in NSCLC and other cancers, focusing on Wnt/ß-catenin signaling. First, we will review the molecular biology of Wnt/ß-catenin signaling, then discuss how it can induce immunoediting and resistance to immune checkpoint inhibitors. We will also describe other various mechanisms of immune-checkpoint-inhibitor resistance. Finally, we will propose therapeutic approaches to overcome these mechanisms.

[Resistance Mechanisms to Immune Checkpoint Inhibitor and Its Overcome with Focus on ß-Catenin in Lung Cancer].

Although the indications for immune checkpoint inhibitors are expanding rapidly, the disease will eventually progress in many patients. Elucidating and overcoming the resistant mechanisms to immune checkpoint inhibitors is a major challenge. WNT/ß-catenin pathway has long been known as one of the mechanisms involved in cell proliferation and epithelial-mesenchymal transition in cancer development. Recently, it has become clear that WNT/ß-catenin pathway also plays a role in cancer immune escape, as reported in melanoma. We have also studied WNT/ß-catenin pathway as a mechanism of immune escape in lung cancer. In this article, we review how WNT/ß-catenin pathway is involved in immune escape and resistance to immune checkpoint inhibitors, mainly in non-small cell lung cancer. In addition, we discuss how to overcome the tumor immune mechanism caused by WNT/ß-catenin pathway in the context of current combination therapies and therapies in development.

[ß-Catenin Expression in Non-Small Cell Lung Cancer and Therapeutic Effect of Immune Checkpoint Inhibitors].

Recently, ß-catenin mediated immune escape mechanism has been reported in several cancers. We investigated whether ß-catenin is associated with resistance to immune checkpoint inhibitor therapy in non-small cell lung cancer. Non-small cell lung cancer patients expressing high levels of ß-catenin showed poor progression-free survival and overall survival after single agent anti-PD-1 therapy. They had less infiltration of CD8-positive cells and antigen-presenting cells. Microarray analysis also showed low gene expression of CD8A and IFNG. siRNA knockdown of CTNNB1 in the ß-catenin-positive lung cancer cell line LK-2 tended to decrease CTNNB1 and ATF3 expression and increase CCL4 expression. The results suggest that ß- catenin suppresses tumor infiltration by antigen-presenting cells and confers resistance to immune checkpoint inhibitors in non-small cell lung cancer via downregulation of CCL4 production.

The clinical significance of tertiary lymphoid structure and its relationship with peripheral blood characteristics in patients with surgically resected non-small cell lung cancer: a single-center, retrospective study.

INTRODUCTION: The presence of tertiary lymphoid structure (TLS) in tumor tissues has been reported to be a factor associated with a good prognosis in several types of cancers. However, the relationship between TLS formation and peripheral blood findings remains unclear. The purposes of the study were to evaluate the effect of the presence of TLS on survival and determine the peripheral blood characteristics associated with TLS formation in non-small cell lung cancer (NSCLC) patients. METHODS: A total of 147 consecutive NSCLC patients who underwent lung resection at Fukushima Medical University Hospital between 2013 and 2017 were enrolled. TLS expression was evaluated, and the relationships between clinical parameters and outcomes were analyzed. Peripheral blood mononuclear cells (PBMCs) were further analyzed by mass cytometry to characterize the TLS-positive microenvironment. RESULTS: Forty-six patients had high TLS expression, and the remaining 101 patients had low TLS expression. In stage II to IV patients (n = 35), disease-free survival was longer in the high TLS expression group (p = 0.027). A low neutrophil to lymphocyte ratio (NLR) < 2.75 in the peripheral blood was associated with high TLS expression (p = 0.003). Citrus analysis after mass cytometry assay showed that the number of cells expressing HLA-DR and CD9 in PBMCs was lower in the high TLS expression group. CONCLUSION: High TLS expression is associated with a good prognosis after surgery in stage II and III NSCLC patients. In the peripheral blood, a low NLR and few antigen-presenting cells indicate the presence of TLS in the tumor microenvironment.

CTLA-4 Expression in Tumor-infiltrating Lymphocytes Is Irrelevant to PD-L1 Expression in NSCLC.

BACKGROUND/AIM: Treatments containing ipilimumab have shown a good outcome in patients with non-small cell lung cancer (NSCLC) regardless of the PD-L1 tumor proportion score (TPS). However, the association between PD-L1 TPS and the expression of CTLA-4 in tumor-infiltrating lymphocytes is unknown. PATIENTS AND METHODS: Fifty-five NSCLC patients who underwent surgery in our hospital were included in this study. We measured the proportions of CTLA-4+ regulatory T cells, and CTLA-4+ CD8 T cells, and statistically analyzed their correlations with the PD-L1 TPS. RESULTS: Statistical correlations were found neither between the proportion of CTLA-4+ regulatory T cells to CD8 T cells and the PD-L1 TPS (p=0.2859) nor between the proportion of CTLA-4+ cells in CD8 T cells and the PD-L1 TPS (p=0.1919). CONCLUSION: The proportions of CTLA-4+ regulatory T cells to CD8 T cells and CTLA-4+ cells in CD8 T cells were irrelevant to the PD-L1 TPS in NSCLC patients.

Tumor ß-catenin expression is associated with immune evasion in non-small cell lung cancer with high tumor mutation burden.

ß-catenin expression by tumor cells suppressed dendritic cell recruitment to the tumor microenvironment in a melanoma model, resulting in fewer tumor-infiltrating lymphocytes. Immunohistochemistry was used in the present study to examine the association between the expression of ß-catenin and tumor infiltrating lymphocytes and CD11c+ cells in 122 patients with non-small cell lung cancer (NSCLC), who underwent radical surgery. ß-catenin was positive in 24% of NSCLC tumors compared with 59% of squamous cell carcinomas and 11% of adenocarcinomas. There was no significant association between the expression of ß-catenin and the frequency of CD8+ cell infiltration into tumor tissues, including the stroma. Conversely, the infiltration of CD8+ cells into tumor nests was significantly lower in ß-catenin-positive cases compared with that in negative ß-catenin cases. Similarly, CD11c+ cell infiltration was significantly lower in the ß-catenin-positive group. The ß-catenin-positive group had shorter overall survival and recurrence-free survival times compared with that in the negative group. Furthermore, ß-catenin-positive NSCLC had a high tumor mutation burden, but tended to have a low expression of programmed death-ligand 1. In conclusion, the expression of ß-catenin in NSCLC was negatively associated with CD11c+ cells and cytotoxic T cell infiltration at the tumor site and had a tendency towards a poor prognosis.

Delta-like 1 homolog (DLK1) as a possible therapeutic target and its application to radioimmunotherapy using 125I-labelled anti-DLK1 antibody in lung cancer models (HOT1801 and FIGHT004).

OBJECTIVES: Delta-like 1 homolog (DLK1) is a non-canonical Notch ligand known to be expressed in several cancers but whose role in lung cancer is not yet fully understood. We sought to confirm DLK1 expression in small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC), and to examine DLK1's clinical significance. Furthermore, we examined the possible utility of DLK1 as a novel target in radioimmunotherapy (RIT). METHODS: We retrospectively assessed the correlation between clinical features and DLK1 expression by immunohistochemistry in resected specimens from 112 patients with SCLC and 101 patients with NSCLC. Moreover, we performed cell and animal experiments, and examined the possibility of RIT targeting DLK1 in SCLC using iodine-125 (125I) -labeled anti-DLK1 antibody, knowing that 125I can be replaced with the alpha-particle-emitter astatine-211 (211At). RESULTS: In SCLC and NSCLC, 20.5 % (23/112) and 16.8 % (17/101) of patients (respectively) had DLK1-positive tumors. In NSCLC, DLK1 expression was associated with recurrence-free survival (P < 0.01) but not with overall survival. In SCLC, there was no association between DLK1 expression and survival. In addition, 125I-labeled anti-DLK1 antibody specifically targeted DLK1 on human SCLC tumor cell lines. Furthermore, 125I-labeled anti-DLK1 antibody was incorporated into tumor tissue in a mouse model. CONCLUSION: A proportion of SCLC and NSCLC exhibits DLK1 expression. As a clinical feature, DLK1 expression could be a promising prognostic factor for recurrence in patients with resected NSCLC. In addition, DLK1 could serve as a new therapeutic target, including RIT, as suggested by our pilot study using a radiolabeled anti-DLK1 antibody in SCLC.

[Monitoring Tumor Infiltrating Lymphocytes by Peripheral Blood in Lung Cancer Patients].

There have been many reports on the association between tumor infiltrating lymphocytes and cancer prognosis. It is known that tumor infiltrating lymphocytes contain not only cytotoxic T lymphocytes but also bystander lymphocytes and immunosuppressive cells. In most of previous reports, tumor infiltrating lymphocytes were defined as CD3 or CD8 T cells. It is generally thought that patients with cancer rich in tumor infiltrating lymphocytes have a good prognosis. Most tumor infiltrating lymphocytes are thought to be cytotoxic T lymphocytes. It is also reported that cancer rich in tumor infiltrating lymphocytes is responsive to immune checkpoint inhibitors. In recent years, several reports revealed clonal replacement in tumor infiltrating lymphocytes after administration of immune checkpoint inhibitors. This change was also detectable in peripheral blood. From the viewpoint of lung cancer treatment, combination of immune checkpoint inhibitors and chemotherapy became the standard therapy. We need to understand the tumor immune microenvironment in order to select the best treatment regimen for each patient. However, it is often difficult to obtain an adequate amount of tissue biopsy sample in standard of care. It is hoped that we can understand the tumor immune microenvironment using the peripheral blood. Thus, studying the association between treatment response, tumor infiltrating lymphocytes, and peripheral blood is considered to be important to research and develop peripheral blood biomarkers in lung cancer.

Genetic alterations in epidermal growth factor receptor-tyrosine kinase inhibitor-naïve non-small cell lung carcinoma.

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) are an approved first-line therapy against unresectable or advanced non-small cell lung cancer (NSCLC) harboring EGFR gene activating mutations. However, the majority of tumors develop acquired resistance against EGFR-TKIs and some tumors exhibit natural resistance. A number of resistance mechanisms against the latest third-generation EGFR-TKIs have been reported, including tertiary EGFR C797S mutation and several gene alterations activating EGFR or other signaling pathways. The current study aimed to identify the frequency of natural EGFR-TKI resistance in pretreatment NSCLC and to predict the therapeutic effect of EGFR-TKIs. A total of 246 EGFR-TKI-naïve NSCLC patients harboring known EGFR gene mutations were identified. The presence of EGFR C797S and T790M mutations were determined using the peptide nucleic acid-locked nucleic acid PCR clamp method. ERBB2, MET, EGFR, ALK, BRAF, FGFR1, MYC, RET, CCND1, CCND2, CDK4, CDK6, MDM2 and MDM4 gene amplification, which can lead to resistance against any generation EGFR-TKIs, was determined using the multiplex ligation-dependent probe amplification assay. No concurrent C797S mutation with known EGFR mutations were identified. T790M mutation was identified in 12 patients (4.9%). ERBB2 or MET gene amplification was found in some patients (0.0-0.4%). MDM2 gene amplification was associated with tumor recurrence and shorter progression-free survival (PFS) for first- or second-generation EGFR-TKIs. De novo EGFR C797S mutation was not identified. Other resistance mechanisms against EGFR-TKIs were indicated in some patients with EGFR-TKI-naïve NSCLC. MDM2 gene amplification, which can lead to altered cell cycle, was associated with tumor recurrence and shorter PFS in EGFR-TKI therapy.

Tumor mutation burden and immunological, genomic, and clinicopathological factors as biomarkers for checkpoint inhibitor treatment of patients with non-small-cell lung cancer.

Cancer treatment using immune checkpoint inhibitors is widely used, although biomarkers predictive of response are not well established. However, both the expressions of programmed cell death ligand 1 (PD-L1) and the tumor mutation burden (TMB) hold promise as such biomarkers for immune checkpoint inhibitors; however, its characteristics and clinical and immunological impacts have not been fully analyzed. We, therefore, evaluated the clinical and immunological parameters related to TMB to identify potential new biomarkers. We enrolled 92 patients with non-small-cell lung cancer who underwent surgery at Fukushima Medical University Hospital from 2013 to 2016. TMB of individual tumors was calculated by whole-exome sequencing analysis. Major cancer-related gene mutations were evaluated using panel sequencing. Expression of PD-L1 and abundance of tumor-infiltrating lymphocytes were evaluated by immunohistochemistry using surgical samples. The median TMB value was 60. TMB was significantly higher in men, current or former smokers, and in patients with squamous cell carcinoma, tumor size ≥ 2.8 cm, wild-type EGFR, TP53 gene mutation-positive status, and cyclin-dependent kinase-inhibitor gene 2A mutation-positive status. According to multivariate analysis, TMB was significantly associated with EGFR gene mutation-negative status (p = 0.0111) and TP53 gene mutation-positive status (p = 0.0425). If TMB is identified as a robust biomarker for immune checkpoint inhibitor administration, analysis of TP53 and EGFR mutations may provide a relatively rapid and easy proxy for predicting TMB.

Prognostic Impact of Tumor Mutation Burden in Patients With Completely Resected Non-Small Cell Lung Cancer: Brief Report.

INTRODUCTION: Tumor mutation burden (TMB) is thought to be associated with the amount of neoantigen in the tumor and to have an important role in predicting the effect of immune checkpoint inhibitors. However, the relevance of TMB to prognosis is not yet fully understood. In this study, we investigated the clinical significance of TMB in patients with NSCLC and examined the relationship between TMB and prognosis. METHODS: We calculated TMB within individual tumors by whole-exome sequencing analysis using next-generation sequencing. We included that there were 90 patients with NSCLC who underwent surgery in the Hospital of Fukushima Medical University from 2013 to 2016. No patients received chemotherapy or immunotherapy before surgery. We assessed the correlation between TMB and prognosis. RESULTS: TMB greater than 62 was associated with worse overall survival (OS) of patients with NSCLC (hazard ratio [HR] = 6.633, p = 0.0003). Multivariate analysis showed poor prognosis with high TMB (HR = 12.31, p = 0.019). In patients with stage I NSCLC, higher TMB was associated with worse prognosis for both OS (HR = 7.582, p = 0.0018) and disease-free survival (HR = 6.07, p = 0.0072). CONCLUSIONS: High TMB in NSCLC is a poor prognostic factor. If high TMB is a predictor of the efficacy of immune checkpoint inhibitors, postoperative adjuvant therapy with immune checkpoint inhibitors may contribute to improvement of recurrence and OS.

Quantitative T-cell repertoire analysis of peripheral blood mononuclear cells from lung cancer patients following long-term cancer peptide vaccination.

Therapeutic cancer peptide vaccination is an immunotherapy designed to elicit cytotoxic T-lymphocyte (CTL) responses in patients. A number of therapeutic vaccination trials have been performed, nevertheless there are only a few reports that have analyzed the T-cell receptors (TCRs) expressed on tumor antigen-specific CTLs. Here, we use next-generation sequencing (NGS) to analyze TCRs of vaccine-induced CTL clones and the TCR repertoire of bulk T cells in peripheral blood mononuclear cells (PBMCs) from two lung cancer patients over the course of long-term vaccine therapy. In both patients, vaccination with two epitope peptides derived from cancer/testis antigens (upregulated lung cancer 10 (URLC10) and cell division associated 1 (CDCA1)) induced specific CTLs expressing various TCRs. All URLC10-specific CTL clones tested showed Ca2+ influx, IFN-γ production, and cytotoxicity when co-cultured with URLC10-pulsed tumor cells. Moreover, in CTL clones that were not stained with the URLC10/MHC-multimer, the CD3 ζ chain was not phosphorylated. NGS of the TCR repertoire of bulk PBMCs demonstrated that the frequency of vaccine peptide-specific CTL clones was near the minimum detectable threshold level. These results demonstrate that vaccination induces antigen-specific CTLs expressing various TCRs at different time points in cancer patients, and that some CTL clones are maintained in PBMCs during long-term treatment, including some with TCRs that do not bind peptide/MHC-multimer.

Family with sequence similarity 83, member B is a predictor of poor prognosis and a potential therapeutic target for lung adenocarcinoma expressing wild-type epidermal growth factor receptor.

Lung adenocarcinoma (ADC) patients with tumors that harbor no targetable driver gene mutation, such as epidermal growth factor receptor (EGFR) gene mutations, have unfavorable prognosis, and thus, novel therapeutic targets are required. Family with sequence similarity 83, member B (FAM83B) is a biomarker for squamous cell lung cancer. FAM83B has also recently been shown to serve an important role in the EGFR signaling pathway. In the present study, the molecular and clinical impact of FAM83B in lung ADC was investigated. Matched tumor and adjacent normal tissue samples were obtained from 216 patients who underwent complete lung resection for primary lung ADC and were examined for FAM83B expression using cDNA microarray analysis. The associations between FAM83B expression and clinicopathological parameters, including patient survival, were examined. FAM83B was highly expressed in tumors from males, smokers and in tumors with wild-type EGFR. Multivariate analyses further confirmed that wild-type EGFR tumors were significantly positively associated with FAM83B expression. In survival analysis, FAM83B expression was associated with poor outcomes in disease-free survival and overall survival, particularly when stratified against tumors with wild-type EGFR. Furthermore, FAM83B knockdown was performed to investigate its phenotypic effect on lung ADC cell lines. Gene silencing by FAM83B RNA interference induced growth suppression in the HLC-1 and H1975 lung ADC cell lines. FAM83B may be involved in lung ADC tumor proliferation and can be a predictor of poor survival. FAM83B is also a potential novel therapeutic target for ADC with wild-type EGFR.

Comparison of surgical outcomes after pneumonectomy and pulmonary function-preserving surgery for non-small cell lung cancer.

BACKGROUND: According to previous reports, lobectomy with bronchoplasty or angioplasty is a more feasible surgery than pneumonectomy for central-type non-small cell lung cancer. However, few studies have compared both the short- and long-term outcomes between pneumonectomy and pulmonary function-preserving surgery. METHODS: From January 2004 to December 2015, 18 patients underwent pneumonectomy (Group PN) and 12 patients underwent pulmonary function-preserving surgery (group PS) at Fukushima Medical University Hospital. Clinicopathological factors were statistically compared between the two groups. RESULTS: The operation times in Group PN and Group PS were 285.9±27.9 and 271.3±99.2 min, respectively (p=0.613), while the amounts of intraoperative bleeding were 324.8±248.9 and 164.5±116.6 g, respectively (p=0.020). The duration of chest drainage and hospitalization after surgery in both groups were not significantly different but there was a tendency toward shorter periods of these durations in Group PS. The 5-year disease-free survival (DFS) rate in Group PN and PS was 51.4% and 74.1%, respectively, without a significant difference (p=0.298). The 5-year overall survival (OS) rate in Group PN and PS was 52.5% and 56.6%, respectively, also without a significant difference (p=0.748). The 5-year OS rate was inferior to the 5-year DFS rate in Group PS, and the 5-year OS rate was not better than the 5-year DFS rate in Group PN. CONCLUSIONS: The short-term results were better in Group PS than PN. However, the long-term results in both groups were similar. Other causes of death influenced OS in both groups; this result might have been affected by the surgical procedures.

The efficacy of the Kampo medicine rikkunshito for chemotherapy-induced anorexia (RICH trial): study protocol for a randomized controlled trial.

BACKGROUND: Cisplatin is a key drug in lung cancer therapy. However, cisplatin is also well known to induce gastrointestinal disorders, such as chemotherapy-induced nausea and vomiting, anorexia, and weight loss. These symptoms sometimes affect patients' quality of life and make continuation of chemotherapy difficult. Anorexia is a cause of concern for patients with cancer because a persistent loss of appetite progresses to cancer cachexia. Although evidence-based management for chemotherapy has recently been established, there is room for improvement. METHODS/DESIGN: This placebo-controlled, double-blind, randomized trial will aim to determine the efficacy of the traditional Japanese Kampo medicine rikkunshito (TJ-43) for preventing anorexia caused by cisplatin-including chemotherapy in patients with lung cancer. Patients with lung cancer who plan to receive cisplatin-including chemotherapy will be recruited. Patients who provide written consent will be randomly allocated to receive either TJ-43 (arm A) or placebo (arm B) for one course of chemotherapy (21 or 28 consecutive days). Investigators and patients will be masked to the treatment assignment throughout the trial. The primary endpoint will be evaluated as the change in dietary intake from day 0 (the day before the start of chemotherapy) to day 7 of cisplatin-including chemotherapy. The two arms of the trial will comprise 30 patients each. From November 2014, a total of 60 patients will be recruited, and recruitment for the study is planned to be complete by October 2017. DISCUSSION: This trial is designed to examine the efficacy of rikkunshito (TJ-43) for reducing anorexia and maintaining food intake caused by cisplatin-including chemotherapy in patients with lung cancer. TRIAL REGISTRATION: Japan Pharmaceutical Information Center Clinical Trials Information (JAPIC CTI), trial registration: JAPIC CTI-142747 . Registered on 15 December 2014; the RICH trial.

Epidermal growth factor receptor mutation status is strongly associated with smoking status in patients undergoing surgical resection for lung adenocarcinoma.

OBJECTIVES: The purpose of this analysis was to examine the relationship between epidermal growth factor receptor (EGFR) mutation status and clinicopathological factors in a cohort of patients who underwent surgical resections for lung adenocarcinoma. METHODS: From the patients who underwent surgical resections for primary lung cancers between 2005 and 2012, 371 consecutive adenocarcinoma patients were enrolled in this study, and their tumours were analysed for EGFR mutations. We examined the clinicopathological factors of all enrolled patients, including age, sex, pathological stage and smoking status and tested for associations with EGFR mutation status. RESULTS: Among the 371 enrolled patients, 195 (52%) patients had EGFR mutations. There were significantly more women, never smokers and tumours of lower grade histology in the EGFR mutation group than in the wild-type group (P < 0.001 each). However, other factors, such as pathological stage and World Health Organization classification, were not significantly associated with mutation status. Multivariable analysis showed that age, smoking history and histological grade were independently associated with EGFR mutations (P = 0.026, P < 0.001 and P < 0.001, respectively), but sex was not. Regarding smoking status, especially, frequency of EGFR mutation decreased, as smoking index increased. On the other hand, sex and smoking cessation (whether the patients were former or current smokers) were not significantly associated with EGFR mutation status. CONCLUSIONS: In our cohort of patients who underwent surgical resection for lung adenocarcinoma, EGFR mutation status was strongly associated with smoking status, especially smoking index.

Efficacy and tolerability of nanoparticle albumin-bound paclitaxel in combination with carboplatin as a late-phase chemotherapy for recurrent and advanced non-small-cell lung cancer: A multi-center study of the Fukushima lung cancer association group of surgeons.

The present retrospective multi-center study aimed to evaluate the efficacy and feasibility of nanoparticle albumin-bound (nab)-paclitaxel plus carboplatin as a second or late-phase chemotherapy in patients with non-small cell lung cancer (NSCLC). A total of 25 patients with recurrent or advanced NSCLC who had received previous chemotherapy were treated with nab-paclitaxel (70-100 mg/m2, intravenously) on days 1, 8 and 15 every 28 days with a carboplatin area under the concentration-time curve of 4-6 on day 1. The overall response rate, disease control rate, progression-free survival (PFS), overall survival (OS) and toxicities were statistically evaluated. Of the 25 patients, there were 9 cases of recurrent disease following surgery, 16 cases of advanced disease, 13 cases of adenocarcinoma, 11 cases of squamous cell carcinoma and 1 case of large cell carcinoma. A total of 13 patients received second-line chemotherapy and 12 received fourth-line or later chemotherapy. One patient exhibited a complete response, 7 had a partial response, 10 exhibited stable disease and 7 had progressive disease. The overall response rate was 32.0% and the disease control rate was 72.0%. The median PFS and median OS following nab-paclitaxel treatment were 4.0 and 14.0 months, respectively. Frequent treatment-associated adverse events were myelosuppression, peripheral neuropathy, gastrointestinal symptoms and baldness, the majority of which were grade 1-2. Grade 3-4 neutropenia, thrombocytopenia and anemia occurred in 7 (28.0%), 3 (12.0%) and 2 (8.0%) patients, respectively. No patients experienced grade 3-4 sensory neuropathy and no grade 5 adverse effects were observed. Nab-paclitaxel plus carboplatin as second-phase or later chemotherapy provided a small but significant survival benefit for patients with recurrent or advanced NSCLC, with tolerable adverse effects. To the best of our knowledge, the results of the present study demonstrated for the first time that nab-paclitaxel plus carboplatin is a promising and feasible late-phase chemotherapeutic agent for NSCLC.

Serum Nitric Oxide as a Predictive Biomarker for Bevacizumab in Non-small Cell Lung Cancer Patients.

BACKGROUND/AIM: Reportedly, hypertension tends to be associated with response to bevacizumab therapy, because bevacizumab suppresses vascular nitric oxide production. In this study we examined the predictive value of nitric oxide in bevacizumab-treated non-small cell lung cancer (NSCLC) patients. PATIENTS AND METHODS: Fifteen patients with advanced or recurrent NSCLC treated with bevacizumab-based regimens were evaluated retrospectively. Serum NOx (NO2-/NO3-) was assayed by the Griess method. RESULTS: Serum nitric oxide levels were decreased after two courses of bevacizumab treatment in our responder group (p=0.02). According to the change in nitric oxide levels after the second course of treatment, median progression-free survival was 11.0 months in the group with decreased serum nitric oxide and 7.6 months in the group with increased serum nitric oxide (p=0.08). CONCLUSION: Serum nitric oxide levels could be a predictive biomarker for response to bevacizumab in NSCLC patients.

Epidermal growth factor receptor gene mutation as risk factor for recurrence in patients with surgically resected lung adenocarcinoma: a matched-pair analysis.

OBJECTIVES: Epidermal growth factor receptor (EGFR) mutation is a robust prognostic factor in patients with lung adenocarcinoma (ADC). However, the role of EGFR mutation status as a recurrence-risk factor remains unknown because the presence of such mutations is associated with other background characteristics. We therefore conducted a matched-pair analysis to compare recurrence-free survival (RFS) in matched cohorts of patients with lung ADC. METHODS: We enrolled 379 patients who underwent surgical resection for lung ADC between 2005 and 2012. We determined the EGFR mutation status of each tumour. Matching their age, gender, smoking history and pathological stage (pStage), we compared RFS between matched cohorts with and without EGFR mutation (n = 86 each). RESULTS: The median age was 67 years, there were 39 (45%) men, 39 (45%) ex- or current smokers and pStage I: 71 (83%), II: 5 (6%), III: 8 (9%), IV: 2 (2%) in each group. The 3- and 5-year RFS rates in patients with mutant and wild-type EGFR were 85 and 78%, and 74 and 60%, respectively, with significant differences between the groups (P = 0.040). Multivariate analysis identified vascular invasion and lymphatic permeation, but not EGFR mutation status, as independent risk factors for recurrence. CONCLUSIONS: EGFR-gene mutation might be a favourable recurrence-risk factor in patients with surgically resected lung ADC, but further studies in larger cohorts are needed to verify this hypothesis.

Clinical significance of expanded Foxp3⁺ Helios⁻ regulatory T cells in patients with non-small cell lung cancer.

The functions of different regulatory T cell (Treg) types in cancer progression are unclear. Recently, expression of the transcription factor Helios was proposed as a marker for natural (non-induced) Tregs. The present study investigated the clinical significance of Helios expression in patients with non-small cell lung cancer (NSCLC). We enrolled 64 patients with NSCLC, of whom 45 were treated surgically and 19 received chemotherapy because of advanced/recurrent disease. Their peripheral blood mononuclear cells were examined by flow cytometry. From the 45 surgery patients, we matched 9 patients with recurrent disease with 9 stage-matched patients without recurrence (n=18), compared their specimens immunohistochemically for tumor infiltrating lymphocytes (TILs) and analyzed these data against clinicopathological factors. Helios expression in Foxp3+ Tregs was 47.5±13.3% in peripheral blood and 18.1±13.4% in tumor specimens. Percentage of Helios- Tregs among CD4+ T cells were significantly higher in the cancer patients (2.4%), especially those with stage IA disease (2.6%) than in healthy donors (1.5%; P<0.001). Patients with low levels of Helios expression in Tregs among their TILs had significantly poorer survival (P=0.038). Helios- Tregs may affect immune suppression, even in early stage NSCLC; they could also be a useful prognostic biomarker in patients with NSCLC, and possibly a novel cancer immunotherapy target.