Identification of subgroup patients with stage IIIB/IV non-small cell lung cancer at higher risk for brain metastases

Trial Design and Optimal Determination of CNS Activity of Small Molecule Targeted Therapy in NSCLC

Central nervous system (CNS) metastases are frequently diagnosed in patients with non-small cell lung cancer (NSCLC). Only recently, clinical trials are broadening eligibility to include patients with brain metastases, offering the potential for some assessment of CNS efficacy to be made. In this work we aim to review the available information on the activity of small molecule targeted drugs for advanced NSCLC with respect to CNS metastases. We analyze a framework for evaluation assessment regarding trials of systemic agents being conducted in patients with, or at risk from, CNS metastases, and provide examples of NSCLC targeted therapies evaluated in the CNS.

Epidermal growth factor receptor mutations and brain metastases in non-small cell lung cancer

Studies have revealed that non-small cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations has a high incidence of brain metastases (BMs). However, the association between EGFR mutations and BMs remains unknown. This review summarizes detailed information about the incidence of BMs, clinical and imaging characteristics of BMs, brain surveillance strategies, influence of treatments on BMs, prognosis after BMs, and differences in EGFR mutations between paired primary tumors and BMs in EGFR-mutated NSCLC. The prognostic results demonstrate that patients with mutated EGFR have a higher incidence of BMs, EGFR tyrosine kinase inhibitors (EGFR-TKIs) (afatinib and osimertinib) delay the development of BMs, and patients with mutated EGFR with synchronous or early BMs have better overall survival after BMs than those with wild-type EGFR. The EGFR mutation status of BM sites is not always in accordance with the primary tumors, which indicates that there is heterogeneity in EGFR gene status between paired primary tumors and BMs. However, the EGFR gene status of the primary site can largely represent that of BM sites. Among patients developing synchronous BMs, patients with mutated EGFR are less likely to have central nervous system (CNS) symptoms than patients with wild-type EGFR. However, the possibility of neuro-symptoms is high in patients with metachronous BMs. Patients with mutated EGFR tend to have multiple BMs as compared to patients with wild-type EGFR. Regarding very early-stage NSCLC patients without neuro-symptoms, regular neuroimaging follow-up is not recommended. Among advanced NSCLC patients with EGFR mutation, liberal brain imaging follow-up in the first several years showed more advantages in terms of cost.

Exosomal miR-4466 from nicotine-activated neutrophils promotes tumor cell stemness and metabolism in lung cancer metastasis

Smoking is associated with lung cancer and has a profound impact on tumor immunity. Nicotine, the addictive and non-carcinogenic smoke component, influences various brain cells and the immune system. However, how long-term use of nicotine affects brain metastases is poorly understood. We, therefore, examined the mechanism by which nicotine promotes lung cancer brain metastasis. In this study, we conducted a retrospective analysis of 810 lung cancer patients with smoking history and assessed brain metastasis. We found that current smoker's lung cancer patients have significantly higher brain metastatic incidence compared to the never smokers. We also found that chronic nicotine exposure recruited STAT3-activated N2-neutrophils within the brain pre-metastatic niche and secreted exosomal miR-4466 which promoted stemness and metabolic switching via SKI/SOX2/CPT1A axis in the tumor cells in the brain thereby enabling metastasis. Importantly, exosomal miR-4466 levels were found to be elevated in serum/urine of cancer-free subjects with a smoking history and promote tumor growth in vivo, suggesting that exosomal miR-4466 may serve as a promising prognostic biomarker for predicting increased risk of metastatic disease among smoker(s). Our findings suggest a novel pro-metastatic role of nicotine-induced N2-neutrophils in the progression of brain metastasis. We also demonstrated that inhibiting nicotine-induced STAT3-mediated neutrophil polarization effectively abrogated brain metastasis in vivo. Our results revealed a novel mechanistic insight on how chronic nicotine exposure contributes to worse clinical outcome of metastatic lung cancer and implicated the risk of using nicotine gateway for smoking cessation in cancer patients.

Non-small cell lung cancer with multiple brain metastases remains relapse-free for more than 13 years: A case report

Brain metastasis (BM) in patients with non-small cell lung cancer (NSCLC) is usually associated with a poor prognosis. A 55-year-old Japanese man visited Tokyo Dental College Ichikawa General Hospital with complaints of motor aphasia and fatigue. Enhanced magnetic resonance imaging of the brain revealed multiple tumors. The patient's medical history included lung cancer surgery performed at another hospital 3 months prior to his visit to our hospital. Total resection of the left frontal tumor revealed BM from lung adenocarcinoma. Stereotactic radiosurgery (SRS) was performed for the remaining three BMs. At 9 months after SRS, another new BM was discovered, and SRS was again performed. More than 13 years have elapsed since the last SRS was performed, and the patient has remained relapse-free. To the best of our knowledge, this is the first case report describing a patient with NSCLC with multiple BMs who has remained relapse-free for >13 years with no neurological dysfunction, including cognitive deficit.

Identification of a high-risk group for brain metastases in non-small cell lung cancer patients

PURPOSE

Identification of a high-risk group of brain metastases (BM) in patients with non-small cell lung cancer (NSCLC) could lead to early interventions and probably better prognosis. The objective of the study was to identify this group by generating a multivariable model with recognized and accessible risk factors.

METHODS

A retrospective cohort from patients seen at a single center during 2010-2020, was divided into a training (TD) and validation (VD) datasets, associations with BM were measured in the TD with logit, variables significantly associated were used to generate a multivariate model. Model´s performance was measured with the AUC/C-statistic, Akaike information criterion, and Brier score.

RESULTS

From 570 patients with NSCLC who met the strict eligibility criteria a TD and VD were randomly assembled, no significant differences were found amid both datasets. Variables associated with BM in the multivariate logit analyses were age [P 0.001, OR 0.96 (95% CI 0.93-0.98)]; mutational status positive [P 0.027, OR 1.96 (95% CI 1.07-3.56); and carcinoembryonic antigen levels [P 0.016, OR 1.001 (95% CI 1.000-1.003). BM were diagnosed in 24% of the whole cohort. Stratification into a high-risk group after simplification of the model, displayed a frequency of BM of 63% (P < 0.001).

CONCLUSION

A multivariate model comprising age, carcinoembryonic antigen levels, and mutation status allowed the identification of a truly high-risk group of BM in NSCLC patients.

Vimentin expression status is a potential biomarker for brain metastasis development in EGFR-mutant NSCLC patients

Background

Despite advances in systemic therapy and improvements in survival for advanced epidermal growth factor receptor (EGFR) mutant non-small cell lung cancer (NSCLC), brain metastasis (BM) remains a poor outcome. Previous studies on risk factors for BM occurrence included unselected patients and biomarker prediction of BM in these populations were not well studied. We aimed to identify the role of epithelial mesenchymal transition (EMT) marker and clinical factors predicting BM in

EGFR

mutant NSCLC patients.

Methods

Advanced EGFR-mutant NSCLC patients in the King Chulalongkorn Memorial Hospital from January 2013 to December 2017 were included. Vimentin expression was assessed by immunohistochemistry. The correlation between vimentin expression and factors associated with BM occurrence was analyzed by univariate and multivariate analyses.

Results

304 patients were enrolled. Of these, 149 patients (49%) developed BM. In multivariate analysis, the occurrence of BM was associated with age <60 years, metastatic disease at diagnosis, and 3 or more metastatic sites. Moreover, positive vimentin expression was also found more common in patients with BM than those without BM (52.4% vs. 27.6%, respectively) and predicted overall BM development in EGFR-mutant patients (OR 2.53, 95% CI, 1.11–5.77; P=0.027). Overall survival (OS) was shorter in vimentin^positive group than in vimentin^negative group. Median OS was 20.0 months (95% CI, 14.51–25.51) and 30.9 months (95% CI, 20.99–40.84), respectively (HR, 1.57; P=0.04).

Conclusions

Younger patients with EGFR-mutant NSCLC who had high disease burden were more likely to develop BM. Vimentin served as a biomarker for predicting BM and poor prognostic factor in EGFR-mutant patients. EMT pathway may be considered as a therapeutic target in these high-risk populations.

Discordance between Fluorescence In Situ Hybridization and Immunohistochemistry Analysis of Anaplastic Lymphoma Kinase Rearrangement in Indian Patients with Non-Small Cell Lung Cancer

Aims  This study aims to evaluate the incidence of anaplastic lymphoma kinase (ALK) mutation in nonsmall cell lung cancer (NSCLC) incorporating fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) methods and to look for any discordance. Methods  We evaluated 101 samples obtained from an enriched cohort of NSCLCs patients from the Army Hospital Research and Referral, New Delhi, India, between November 2016 and November 2018. IHC was performed using the highly-sensitive D5F3 rabbit monoclonal primary antibody. FISH was performed with dual-color, break-apart probe (ZytoLight SPEC) on formalin-fixed, and paraffin-embedded tissue. Discordance between IHC and FISH for ALK rearrangements was evaluated. Pearson correlation coefficient ( r ) was performed to identify any association of ALK presence (by IHC and FISH) with smoking brain metastasis, programmed death-ligand (PD-L1) expression, pleural effusion, and histopathological subtype. Results  A total of 7.92% (8/101) cases tested by IHC and 9.9% (10/101) cases tested by FISH were positive for ALK rearrangement. Of 93 ALK IHC-negative cases, 4 were ALK FISH-positive, whereas of 91 ALK FISH-negative cases, 4 were ALK IHC-positive cases. The correlation analysis demonstrated no or very weak correlation in ALK mutations by IHC or FISH with smoking, brain metastasis, PD-L1 expression, pleural effusion, and histopathological examination, except a weak positive correlation ( r = 0.33) observed between brain metastasis and ALK rearrangement identified by FISH. Conclusions  Our study demonstrated a somewhat similar incidence of ALK FISH-positive cases and ALK IHC-positive cases, though the incidence was numerically higher for ALK-FISH method.

Development of dual-targeted nano-dandelion based on an oligomeric hyaluronic acid polymer targeting tumor-associated macrophages for combination therapy of non-small cell lung cancer

In this study, the novel carrier materials were screened to structure targeting nano-micelles (named ‘nano-dandelion’) for synchronous delivery of curcumin (Cur) and baicalin (Bai), which could effectively overcome the tumor resistance. Mannose (Man) was found to bind better to CD206 receptors on the surface of tumor-associated macrophages (TAMs), thereby increasing the number of nano-dandelion engulfed by TAMs. Furthermore, oligomeric hyaluronic acid (oHA) was able to target CD44 receptors, resulting in recruitment of a higher number of nano-dandelion to locate and engulf tumor cells. The disulfide bond (S–S) in 3,3′-dithiodipropionic acid (DA) could be broken by the high concentration of glutathione (GSH) in the tumor microenvironment (TME). Based on this, we selected DA to connect hydrophobic fragments (quercetin, Que) and oHA. A reduction-sensitive amphiphilic carrier material, quercetin–dithiodipropionic acid–oligomeric hyaluronic acid–mannose–ferulic acid (Que–S–S–oHA–Man–FA; QHMF) was fabricated and synthesized by ¹H NMR. Next, QHMF self-assembled into nano-dandelion, i.e. encapsulated Cur and Bai in water. Critical experimental conditions in the preparation process of nano-dandelion that could affect its final properties were explored. Nano-dandelion with a small particle size (121.0 ± 15 nm) and good normal distribution (PI = 0.129) could easily enter tumor tissue through vascular barrier. In addition, nano-dandelion with a suitable surface potential (–20.33 ± 4.02 mV) could remain stable for a long duration. Furthermore, good cellular penetration and tumor cytotoxicity of nano-dandelion were demonstrated through in vitro cellular studies. Finally, effective antitumor activity and reduced side effects were confirmed through in vivo antitumor experiments in A549 tumor-bearing nude mice.

Risk factors of brain metastases as initial failure in completely resected stage IIIA(N2) non-small cell lung cancer

Background

This study aimed to identify the risk factors of brain metastases (BM) as the initial site of failure in patients with completely resected stage IIIA (N2) non-small-cell lung cancer (NSCLC).

Methods

From January 2005 and June 2012, the clinical data of 357 patients with completely resected stage IIIA (N2) NSCLC were reviewed in this study. Kaplan-Meier analysis was used to identify the incidence of BM as the initial site of failure and survival. To assess the risk factors of BM, the log-rank test and Cox regression were used for univariate analysis and multivariate analysis, separately.

Result

Seventy-three (20.4%) patients developed BM; 60 patients had BM as their initial site of failure. The 1-, 3-, and 5-year risk for patients developing BM as the initial site of failure was 9.1%, 27.4% and 35.4%, respectively. Univariate analysis showed adenocarcinoma histology (P=0.000), number of regional LN >4 (P=0.018), multiple N2 stations (P=0.027), multiple region of LN involvement (P=0.010) were significantly associated with an increased risk of developing BM as the initial site of failure. Multivariate analysis showed adenocarcinoma (P=0.001; HR =0.150; 95% CI, 0.047–0.479), multiple regions of LN involvement (P=0.015; HR =2.010; 95% CI, 1.146–3.524) were significantly associated with the high risk of developing BM as the initial site of failure. In patients with adenocarcinoma and multiple regions of LN involvement, the 5-year actuarial risk of BM as the initial failure was 47.6%, respectively.

Conclusions

Adenocarcinoma and multiple regions of LN involvement were independent risk factors for BM as the initial failure in completely resected stage IIIA (N2) NSCLC. Prospective clinical trials are needed to verify the effect of PCI in the highest-risk subset we identified.

Effects of single-nucleotide polymorphisms in the mTORC1 pathway on the risk of brain metastasis in patients with non-small cell lung cancer

Purpose

The mammalian target of rapamycin complex 1 (mTORC1) signaling pathway plays a vital role in cancer development and progression. This study aimed to investigate the relationship between genotype variants in mTORC1 pathway and the risk of brain metastasis (BM) in patients with non-small cell lung cancer (NSCLC).

Methods

We extracted genomic DNA from blood samples of 501 NSCLC patients and genotyped eight single-nucleotide polymorphisms (SNPs) in three core genes [mammalian target of rapamycin (mTOR), mammalian lethal with sec-13 protein 8 (mLST8) and regulatory-associated protein of mTOR (RPTOR)] of the mTORC1 pathway. The associations between these SNPs and the risk of BM development were assessed.

Results

The AG/GG genotype of mLST8:rs26865 and TC/CC genotype of mLST8:rs3160 were associated with an increased risk of BM [hazard ratios (HR) 2.938, 95% confidence interval (CI) 1.664–5.189, p < 0.001 and HR = 2.490, 95% CI = 1.543–4.016, p < 0.001, respectively]. These risk polymorphisms had a cumulative effect on BM risk, with two risk genotypes exhibiting the highest increased risk (p < 0.001). Furthermore, these risk SNPs were associated with the lymph node metastasis (N2/3), body mass index (BMI) (≥ 25 kg/m²), high level of squamous cell carcinoma (SCC) antigen and Ki-67 proliferation index. Moreover, patients with AG/GG genotype of mLST8:rs26865 had significantly lower median overall survival than those with AA genotype (12.1 months versus 21.6 months, p = 0.04).

Conclusions

Our results indicate that polymorphisms in mTORC1 pathway were significantly associated with increased risk of BM and may be valuable biomarkers to identify NSCLC patients with a high risk of BM.

Electronic supplementary material

The online version of this article (10.1007/s00432-019-03059-y) contains supplementary material, which is available to authorized users.

LPCAT1 promotes brain metastasis of lung adenocarcinoma by up-regulating PI3K/AKT/MYC pathway

Background

Brain metastasis (BM) is associated with poor prognosis, recurrence, and death in patients with non-small cell lung cancer (NSCLC). Lysophosphatidylcholine acyltransferase 1 (LPCAT1) has been reported to be involved in the progression, metastasis and recurrence of malignancies. However, the potential role of LPCAT1 in NSCLC remains poorly understood. This study was aimed to identify genes involved in lung adenocarcinoma (LUAD) brain metastasis, and look into the role of LPCAT1 in LUAD progression.

Methods

We used integrative genomic analysis to identify genes involved in lung adenocarcinomas. LPCAT1 expression was evaluated in tumor tissues from LUAD patients and LUAD cell lines. The role of LPCAT1 was subsequently investigated both in vitro and in vivo. The mechanism underlying the involvement of LPCAT1 in LUAD progression was explored with the activator of PI3K/AKT pathway. RNA sequencing was performed to confirm the involvement of LPCAT1 and associated pathway in LUAD brain metastasis.

Results

LPCAT1 was up-regulated in LUAD tissues and cell lines. shRNA-mediated depletion of LPCAT1 not only abrogated cell proliferation, migration and invasion in vitro, but also arrested tumor growth and brain metastases in vivo. Notably, LPCAT1 at least partially influenced LUAD progression through PI3K/AKT signal pathway by targeting MYC transcription. Moreover, expression of LPCAT1 was higher in tissues of LUAD patients with BM than those without BM as revealed by IHC staining, RNA-Sequencing and qPCR analysis. Finally, elevated LPCAT1 expression in patients with lung adenocarcinomas was associated with a poor clinical outcome.

Conclusions

This study showed that LPCAT1 works as a regulator of cell metastasis and may serve as a novel therapeutic target for BM in lung adenocarcinoma.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1092-4) contains supplementary material, which is available to authorized users.

Histopathologic analysis of brain metastasis in pulmonary adenocarcinoma: Necrosis is a new risk factor

BACKGROUND

Studies have shown that 30-50% of non-small cell lung cancer (NSCLC) patients develop brain metastasis (BM). Since BM shortens overall survival and decreases the quality of life, early detection and treatment of BM are vital. While data are available for clinical risk factors of NSCLC with BM, histopathological factors are not well understood. Therefore, we evaluated the histopathological related factors which will help early detection and selection of effective treatment options.

MATERIALS AND METHODS

A total of 117 surgical lung specimens diagnosed as NSCLC with BM were included as a study group. We included 237 cases without BM as a control group. One pathologist reviewed H&E slides and analyzed the histopathologic factors of all cases.

RESULTS

In pulmonary adenocarcinoma, vascular invasion, N stage, micropapillary pattern and necrosis were significantly associated with BM in multivariate analysis (vascular invasion, p = 0.009; micropapillary pattern, p = 0.024; others, p < 0.001). Tumor with extensive necrosis had higher hazard ratio and shorter time to BM (p < 0.001).

CONCLUSION

Our findings suggest that necrosis is a new predictive factor of BM in pulmonary adenocarcinoma. Short term follow-up is needed especially when extensive necrosis is present.

Prognostic factors and outcome of surgically treated patients with brain metastases of non-small cell lung cancer

Background

Brain metastases (BM) are a common consequence of lung cancer and surgery is effective; however, the factors affecting survival after surgery are unclear. The aim of this study was to identify the outcomes and prognoses of post‐metastasectomy patients with BM from non‐small cell lung cancer (NSCLC) at a single institution over a 15‐year period.

Methods

NSCLC patients who had undergone BM surgery were retrospectively identified. Survival was analyzed using the Kaplan–Meier curve, and univariate and multivariate factors associated with survival were identified using the Cox proportional hazards model.

Results

The median overall survival was 9.8 months, 18 (14.8%) patients survived > 24 months, and 6 (4.9%) > 36 months. The one and two‐year survival rates were 41% and 18.6%, respectively. Univariate analysis revealed that recursive partitioning analysis (RPA) classification, Karnofsky Performance Scale (KPS) scores, BM number, extracranial metastasis status, different lesion locations, resection extent, postoperative treatment, and salvage therapy after recurrence significantly influenced patient survival. The different treatment modalities for primary lesions also affected postoperative survival. KPS ≥ 70, RPA class I/II, and postoperative chemotherapy were independent factors that decreased the risk of death from BM. Interestingly, the initial onset of intracranial lesions could increase the risk of death from BM.

Conclusion

A KPS score ≥ 70, RPA class I/II, and postoperative chemotherapy could benefit post‐metastasectomy patients with BM from NSCLC. Conversely, the initial onset of intracranial lesions is an unfavorable factor that increases the risk of death. These findings support the use of personalized therapy for patients with BM from NSCLC.

MicroRNA-98-5p inhibits proliferation and metastasis in non-small cell lung cancer by targeting TGFBR1

MicroRNAs (miRNAs or miRs) have recently emerged as key regulators of various types of cancer, including non‑small cell lung cancer (NSCLC). The disrupted expression of miRNAs is associated with tumorigenesis and metastasis; however, the underlying mechanisms remain unclear. In this study, we demonstrate that miR‑98‑5p is downregulated in NSCLC and that miR‑98‑5p deficiency is associated with an advanced clinical stage and metastasis. A dual‑luciferase reporter assay was performed to confirm that transforming growth factor beta receptor 1 (TGFBR1), a key stimulator of tumor proliferation and metastasis, was a direct target of miR‑98‑5p. miR‑98‑5p overexpression resulted in the downregulation of TGFBR1 and the suppression of the viability, proliferation, migration and invasion of A549 and H1299 cells. Furthermore, miR‑98‑5p was demonstrated to be an efficient suppressor of tumor growth in an A549 subcutaneous xenograft tumor mouse model. Finally, miR‑98‑5p overexpression exerted a significant anti‑metastatic effect in a mouse model of pulmonary metastasis. On the whole, the results of the present study suggest that miR‑98‑5p/TGFBR1 may serve as promising targets for NSCLC therapy.

Brain metastases in ALK-positive NSCLC - time to adjust current treatment algorithms

The progress in molecular biology has revolutionized systemic treatment of advanced non-small-cell lung cancer (NSCLC) from conventional chemotherapy to a treatment stratified by histology and genetic aberrations. Tumors harboring a translocation of the anaplastic-lymphoma-kinase (ALK) gene constitute a distinct genetic and clinico-pathologic NSCLC subtype with patients with ALK-positive disease being at a higher risk for developing brain metastases. Due to the introduction of effective targeted therapy with ALK-inhibitors, today, patients with advanced ALK-positive NSCLC achieve high overall response rates and remain progression-free for long time intervals. Moreover, ALK-inhibitors seem to exhibit efficacy in the treatment of brain metastases. In the light of this, it needs to be discussed how treatment algorithms for managing patients with brain metastases should be modified. By integrating systemic ALK-inhibitor therapy, radiotherapy, in particular whole brain radiotherapy might be postponed deferring potential long-term impairment by neurocognitive deficits to a later time point in the course of the disease. An early treatment of asymptomatic brain metastases might offer patients a longer time without impairment of cerebral symptoms or radiotherapeutic interventions. Based on an updated extensive review of the literature this article provides an overview on the epidemiology and the treatment of patients’ brain metastases. It describes the specifics of ALK-positive disease and proposes an algorithm for the treatment of patients with advanced ALK-positive NSCLC and brain metastases.

A retrospective analysis in patients with EGFR-mutant lung adenocarcinoma: is EGFR mutation associated with a higher incidence of brain metastasis?

Lung adenocarcinomas are more commonly associated with brain metastases (BM). Epidermal growth factor receptor (EGFR) mutations have been demonstrated to be both predictive and prognostic for patients with lung adenocarcinoma. We aimed to explore the potential association between EGFR mutation and the risk of BM in pulmonary adenocarcinoma patients. Data of 234 patients from 2007 to 2014 were retrospectively reviewed. A total of 108 patients had EGFR mutations in the entire cohort. Among them, 76 patients developed BM during their disease course. The incidence of BM was statistically higher in patients with EGFR mutations both at initial diagnosis (P=0.014) and at last follow-up (P<0.001). Multivariate logistic regression analysis revealed that EGFR mutation significantly increased the risk of BM at initial diagnosis (OR=2.515, P=0.022). In patients without BM at initial diagnosis, the accumulative rate of subsequent BM was significantly higher with EGFR mutations (P=0.001). Multivariate Cox regression analysis identified EGFR mutation as the only independent risk factor for subsequent BM (HR=3.036, P=0.001). Patients with EGFR mutations demonstrated longer overall survival (OS) after BM diagnosis than patients with wild-type EGFR (P=0.028). Our data suggest that EGFR mutation is an independent predictive and prognostic risk factor for BM and a positive predictive factor for OS in patients with BM.

miR-455-5p promotes cell growth and invasion by targeting SOCO3 in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer. miR-455-5p has increased expression and the ability to promote tumorigenesis in certain cancers. However, the role of miR-455-5p in NSCLC has not been sufficiently investigated. SOCS3 (suppressor of cytokine signaling 3), an important tumor suppressor, is often aberrantly inactivated in various tumors, but it is currently unclear whether SOCO3 is a target of miR-455-5p. In the present study, we investigated the role of miR-455-5p in NSCLC. We found that the expression of miR-455-5p was up-regulated in NSCLC tumor tissues compared to corresponding noncancerous tissues, and its expression was correlated with metastasis and tumor node metastasis in NSCLC tissue. We then showed that miR-455-5p promoted migration, invasion and proliferation in NSCLC cell lines. Additionally, we also found that SOCS3 was the direct target gene of miR-455-5p. Consistently, the expression of SOCS3 was negatively correlated with the expression of miR-455-5p in NSCLC tissues. We further show that aberrant miR-455-5p expression is partially controlled by activated ERK signaling in NSCLC. Therefore, miR-455-5p could enhance the growth and metastasis of NSCLC by inhibiting SOCS3, thus providing a potential molecular therapeutic target for the treatment of NSCLC patients.

Brain metastases in patients with non-small cell lung cancer: the role of mutated-EGFRs with an exon 19 deletion or L858R point mutation in cancer cell dissemination

Non-small cell lung cancer (NSCLC) patients tend to develop brain metastases (BM), but the link between BM occurrence and driver mutations in NSCLC is not very clear. We explored whether activating mutations of epidermal growth factor receptors (EGFRs) in exon 19 deletion or L858R predict BM in NSCLC. A retrospective multivariable logistic regression analysis of 384 patients demonstrated that the presence of mutated-EGFRs was associated with overall BM (OR=2.24, P=0.001) compared to that of wild-type EGFR (WT-EGFR). Moreover, the time-to-event analysis model considering death as a competing risk revealed that, irrespective of survival, mutated-EGFRs predicted subsequent BM (SBM) in stage IIIB-IV patients (37.1% vs. 10.6%, HR=2.98, P=0.002) after adjusting for age (HR=2.00, P=0.012), gender, histological subtype, and smoking history. Notably, the younger mutated-EGFR subgroup was at a higher risk for SBM compared to the older WT-EGFR one (58.1% vs.10.9%, HR=6.57, P<0.001). Additionally, EGFR exon 19 deletion, despite having a slightly longer overall survival (20.6 vs. 14.2 months, P=0.368), was comparable to L858R mutation in predicting SBM (39.5% vs. 34.5%, HR=0.91, P=0.770). In vitro, the overexpression of mutated-EGFRs induced morphological changes towards a mesenchymal-like phenotype and promoted mobility in lung cancer cells. Clinically, mutated-EGFR NSCLC displayed a higher proportion of vimentin-positive expression (75.3% vs. 51.2%; P=0.007) and a shorter median time to SBM (23.5 months vs. not reached, P=0.017) than WT-EGFR NSCLC. These results suggest that NSCLC patients carrying mutated-EGFRs may require a higher frequency of brain imaging assessments than those with WT-EGFR to facilitate earlier SBM detection during follow-up.

CUTL1 induces epithelial-mesenchymal transition in non-small cell lung cancer

The homeobox transcription factor CUTL1 has been associated with cellular proliferation and cell cycle progression, and CUTL1 functions as an oncogene. The aim of the present study was to investigate whether CUTL1 participates in epithelial-mesenchymal transition (EMT). The expression levels of CUTL1, E-cadherin, N-cadherin and Snail were determined by immunohistochemistry assay, immunofluorescence assay or real-time quantitative reverse transcription PCR. Their roles in non-small cell lung cancer (NSCLC) were assessed by functional analyses. Protein expression was detected by western blot analysis. The CUTL1 expression levels are higher in non-small cell lung cancer (NSCLC) tissues. High CUTL1 expression in NSCLC is associated with the mesenchymal-like phenotype. Mechanistically, CUTL1 upregulates transforming growth factor β receptor I (TβR-I) expression, and the TβR-I inhibitor SB431542 abolishes EMT elicited by ectopic CUTL1 expression. Transforming growth factor β (TGF-β) signaling is essential for CUTL1-induced EMT in NSCLC cells. CUTL1 is downstream of TGF-β signaling and CUTL1 is involved in the expression of the TβR-I. This study indicates that CUTL1 may be a potential target for anti-lung cancer therapy.

Methods and results of locoregional treatment of brain metastases in patients with non-small cell lung cancer

This article presents methods and results of surgery and radiotherapy of brain metastases from non-small cell lung cancer (BMF-NSCLC). Patients with single BMF-NSCLC, with Karnofsky score ≥ 70 and controlled extracranial disease are the best candidates for surgery. Stereotactic radiosurgery (SRS) is recommended in patients with 1-3 BMF-NSCLC below 3-3.5 cm, with minor neurological symptoms, located in parts of the brain not accessible to surgery, with controlled extracranial disease. Whole brain radiotherapy (WBRT) following SRS reduces the risk of local relapse; in selected patients median survival reaches more than 10 months. Whole brain radiotherapy alone is a treatment in patients with multiple metastases, poor performance status, uncontrolled extracranial disease, disqualified from surgery or SRS with median survival 3 to 6 months. There is no doubt that there are patients with BMF-NSCLC who should receive only the best supportive care. There is a debate in the literature on how to select these patients.

Erlotinib plus bevacizumab as an effective treatment for leptomeningeal metastases from EGFR mutation-positive non-small cell lung cancer

Leptomeningeal metastasis is a severe complication of non-small cell lung cancer. Its prognosis is very poor and conventional treatments have limited efficacy. However, epidermal growth factor receptor-tyrosine kinase inhibitors have exhibited high response rates in EGFR mutation-positive lung cancer patients with central nervous system metastases. It has been postulated that this could be due to the penetration of agents into the central nervous system and a high cerebrospinal fluid concentration is a key consideration in measuring treatment effect. Bevacizumab has also been used as an effective therapeutic agent in patients with central nervous system metastases. However, the efficacy of epidermal growth factor receptor-tyrosine kinase inhibitor doublet therapy for leptomeningeal metastases and the cerebrospinal fluid penetration of epidermal growth factor receptor-tyrosine kinase inhibitors have yet to be determined. Moreover, the safety of this doublet regimen in patients with a poor general condition is not known. Herein, we report on a case treated with erlotinib plus bevacizumab for leptomeningeal metastases from EGFR mutation-positive non-small cell lung cancer. The patient's performance status significantly improved and the cerebrospinal fluid penetration rate of erlotinib plus bevacizumab was equal to or greater than the past reports of erlotinib alone.

Incidence of Brain Metastasis at the Initial Diagnosis of Lung Squamous Cell Carcinoma on the Basis of Stage, Excluding Brain Metastasis

INTRODUCTION

Current National Comprehensive Cancer Network guidelines recommend routine brain magnetic resonance imaging (MRI) screening in patients with stage II to IV non-small cell carcinoma, regardless of histological subtype. This recommendation might not be universally applicable, however, because brain metastasis (BM) is seen less frequently in patients with lung squamous cell carcinoma (SCC) than in those with a histological diagnosis of nonsquamous cell carcinoma.

METHODS

The cases of 564 patients with lung SCC in our institution between January 2012 and December 2013 were reviewed prospectively for comprehensive staging. All subjects' lung SCC, but not their BM, was staged on the basis of the seventh edition of the guidelines of the American Joint Committee on Cancer. We evaluated the incidence of BM across the stages and clinical factors associated with BM.

RESULTS

Of the 564 patients, 28 (5.0%) had BM. BM did not occur in patients with stage Ia or Ib disease; however, it increased significantly as the disease progressed from stage IIa to IV (p < 0.001, trend test). Multivariate analysis showed that tumor involvement in N3 lymph nodes and distant metastasis other than BM (M1b) was independently associated with the development of BM.

CONCLUSIONS

Routine brain MRI screening in patients with lung SCC in stage II to IV can help to evaluate asymptomatic BM. By contrast, we did not find any evidence supporting routine brain MRI screening in patients with stage I disease.

Brain metastases in malignant pleural mesothelioma

The brain is a rare site of metastasis in malignant pleural mesothelioma (MPM), and its clinical features and prognosis remain unclear. The aim of this study was to investigate the incidence, prognosis, and risk factors for brain metastases (BM) in MPM patients. Between July 1993 and October 2014, 150 patients with histologically proven MPM were included in this retrospective study. The cumulative incidence of BM was estimated with the Kaplan-Meier method, and differences between groups were analyzed by the log-rank test. Multivariate logistic regression analysis was applied to assess risk factors for BM. The median follow-up time was 11 months (range 0-154.0 months). A total of eight patients (5.3 %) developed BM during the course of their illness. Multivariate analysis identified age <65 years (odds ratio [OR] = 5.83, p = 0.038) and International Mesothelioma Interest Group stage IV (OR = 1.69, p = 0.040) as independent factors related to increased risk of developing BM. The 1-and 2-year cumulative rates of BM were 4.0 % (95 % confidence intervals [CI] 1.4-8.5 %) and 5.3 % (95 % CI 2.3-10.2 %), respectively. Our study showed that the overall survival (OS) of patients with BM was worse than that of patients without BM (median OS 6.5 vs. 11.0 months, p = 0.037). The prognosis for BM in MPM patients is poor. Clinicians should perform careful screening for BM, especially in patients with risk factors.

Outcome of surgical resection for brain metastases and radical treatment of the primary tumor in Chinese non-small-cell lung cancer patients

Purpose

Brain metastasis is the most common complication of brain cancer; nevertheless, primary lung cancer accounts for approximately 20%–40% of brain metastases cases. Surgical resection is the preferred treatment for brain metastases. However, no studies have reported the outcome of surgical resection of brain metastases from non–small-cell lung cancer (NSCLC) in the People’s Republic of China. Moreover, the optimal treatment for primary NSCLC in patients with synchronous brain metastases is hitherto controversial.

Patients and methods

We retrospectively analyzed the cases of NSCLC patients with brain metastases who underwent neurosurgical resection at the Sun Yat-sen University Cancer Center, and assessed the efficacy of surgical resection and the necessity of aggressive treatment for primary NSCLC in synchronous brain metastases patients.

Results

A total of 62 patients, including 47 men and 15 women, with brain metastases from NSCLC were enrolled in the study. The median age at the time of craniotomy was 54 years (range 29–76 years). At the final follow-up evaluation, 50 patients had died. The median OS time was 15.1 months, and the survival rates were 70% and 37% at 1 and 2 years, respectively. The median OS time of synchronous brain metastases patients was 12.5 months. Univariate analysis revealed that radical treatment of primary NSCLC was positively correlated with survival, and it was an independent prognostic factor in the multivariate analysis.

Conclusion

Surgical resection is an effective treatment for brain metastases. Besides craniotomy, radical therapy is necessary for the management of primary NSCLC in patients with synchronous brain metastases.

Efficacy of the irreversible ErbB family blocker afatinib in epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI)-pretreated non-small-cell lung cancer patients with brain metastases or leptomeningeal disease

INTRODUCTION

Afatinib is an effective first-line treatment in patients with epidermal growth factor receptor (EGFR)-mutated non-small-cell lung cancer (NSCLC) and has shown activity in patients progressing on EGFR-tyrosine kinase inhibitors (TKIs). First-line afatinib is also effective in patients with central nervous system (CNS) metastasis. Here we report on outcomes of pretreated NSCLC patients with CNS metastasis who received afatinib within a compassionate use program.

METHODS

Patients with NSCLC progressing after at least one line of chemotherapy and one line of EGFR-TKI treatment received afatinib. Medical history, patient demographics, EGFR mutational status, and adverse events including tumor progression were documented.

RESULTS

From 2010 to 2013, 573 patients were enrolled and 541 treated with afatinib. One hundred patients (66% female; median age, 60 years) had brain metastases and/or leptomeningeal disease with 74% having documented EGFR mutation. Median time to treatment failure for patients with CNS metastasis was 3.6 months, and did not differ from a matched group of 100 patients without CNS metastasis. Thirty-five percent (11 of 31) of evaluable patients had a cerebral response, five (16%) responded exclusively in brain. Response duration (range) was 120 (21-395) days. Sixty-six percent (21 of 32) of patients had cerebral disease control on afatinib. Data from one patient with an impressive response showed an afatinib concentration in the cerebrospinal fluid of nearly 1 nMol.

CONCLUSION

Afatinib appears to penetrate into the CNS with concentrations high enough to have clinical effect on CNS metastases. Afatinib may therefore be an effective treatment for heavily pretreated patients with EGFR-mutated or EGFR-TKI-sensitive NSCLC and CNS metastasis.