A Sensitive Assay for Unbound Docetaxel Using Ultrafiltration plus HPLC-MS and Its Application to a Clinical Study.

INTRODUCTION: Docetaxel, a taxane used in the treatment of solid tumours, exerts pharmacological activity when in its unbound form. We report a sensitive assay to quantify unbound docetaxel after oral administration of docetaxel plus encequidar (oDox+E). Unbound drug quantification is important due to its direct correlation with drug-related toxicity and therapeutic efficacy. We improve on the sensitivity of current assay methods and demonstrate the utility of the assay on a novel formulation of oral docetaxel. METHODS: Ultrafiltration followed by high-performance liquid chromatography and tandem mass spectrometry (HPLC-MS/MS) was utilized. Long-term stability, precision, accuracy, and recovery experiments were conducted to validate the assay. Additionally, patient samples from a Phase I dose-escalation pharmacokinetic study were analyzed using the developed assay. RESULTS: The assay method exhibited long-term stability with an observed change between 0.8 and 6.9% after 131 days of storage at -60 °C. Precision and accuracy quality controls met the FDA acceptance criteria. An average recovery of 88% was obtained. Patient sample analysis demonstrated successful implementation of the assay. CONCLUSION: A validated sensitive assay was developed with an LLOQ of 0.084 ng/mL using 485 µL of human plasma. The sensitivity of the assay allowed quantification of unbound docetaxel concentrations in an early-phase oDox+E clinical study to compare it against IV docetaxel using pharmacokinetic modelling. Successful development of oDox+E represents an opportunity to replace the current IV docetaxel regimen with an oral regimen with lower cost, decreased side effects, and improve patient quality of life and experience.

Oral docetaxel plus encequidar - a phase 1 clinical trial.

PURPOSE: To determine the bioavailability, safety, and tolerability of a single dose of oral docetaxel plus encequidar (oDox + E) and compare its pharmacokinetic exposure with current standard of care IV docetaxel. INTRODUCTION: Docetaxel is a taxane widely used as an anti-neoplastic agent. Due to low oral bioavailability secondary to gut P-glycoprotein (P-gp) efflux, its current use is limited to intravenous administration. Oral docetaxel may provide a less resource intensive, more convenient, and tolerable alternative. Encequidar is a first in class, minimally absorbed, oral gut-specific P-gp inhibitor. We tested whether oDox + E can achieve comparable pharmacokinetic exposure to IV docetaxel. METHODS: A multicentre, phase I open-label, pharmacokinetic trial was undertaken to determine the bioavailability, safety, and tolerability of a single dose of oDox + E (at 75 mg/m2 + 15 mg, 150 mg/m2 + 15 mg, and 300 mg/m2 + 15 mg) in metastatic prostate cancer (mPC) patients compared to standard of care IV docetaxel as prescribed by their oncologists. The 15 mg of Encequidar at each dose level was given one hour prior to oral docetaxel. RESULTS: 11 patients were enrolled; 9 patients completed the study. Oral docetaxel exposure increased with dose, achieving the highest at 300 mg/m2 oDox + E (with AUC0 - infinity of 1343.3 ± 443.0 ng.h/mL compared to the IV docetaxel AUC0 - infinity of 2000 ± 325 ng.h/mL) and became non-linear at 300 mg/m2. The mean absolute bioavailability of oDox + E across all 3 dose levels was 16.14% (range: 8.19-25.09%). No patient deaths, dose limiting toxicity, treatment-related serious adverse event or grade 4 toxicity were observed. Maximal tolerated dose was not reached. CONCLUSION: oDox + E has a safe and tolerable adverse event profile in patients with metastatic prostate cancer. The increase in oral bioavailability of oDox + E suggests a multi-dose oDox + E regimen could theoretically achieve exposures comparable with standard of care IV docetaxel. Further development to examine the optimal multiple dose regimen of oDox + E is warranted. TRIAL REGISTRATION NUMBER: U1111-1173-5473.

Oral docetaxel plus encequidar - A pharmacokinetic model and evaluation against IV docetaxel.

The development of optimized dosing regimens plays a crucial role in oncology drug development. This study focused on the population pharmacokinetic modelling and simulation of docetaxel, comparing the pharmacokinetic exposure of oral docetaxel plus encequidar (oDox + E) with the standard of care intravenous (IV) docetaxel regimen. The aim was to evaluate the feasibility of oDox + E as a potential alternative to IV docetaxel. The article demonstrates an approach which aligns with the FDA's Project Optimus which aims to improve oncology drug development through model informed drug development (MIDD). The key question answered by this study was whether a feasible regimen of oDox + E existed. The purpose of this question was to provide an early GO / NO-GO decision point to guide drug development and improve development efficiency. METHODS:  A stepwise approach was employed to develop a population pharmacokinetic model for total and unbound docetaxel plasma concentrations after IV docetaxel and oDox + E administration. Simulations were performed from the final model to assess the probability of target attainment (PTA) for different oDox + E dose regimens (including multiple dose regimens) in relation to IV docetaxel using AUC over effective concentration (AUCOEC) metric across a range of effective concentrations (EC). A Go / No-Go framework was defined-the first part of the framework assessed whether a feasible oDox + E regimen existed (i.e., a PTA ≥ 80%), and the second part defined the conditions to proceed with a Go decision. RESULTS:  The overall population pharmacokinetic model consisted of a 3-compartment model with linear elimination, constant bioavailability, constant binding mechanics, and a combined error model. Simulations revealed that single dose oDox + E regimens did not achieve a PTA greater than 80%. However, two- and three-dose regimens at 600 mg achieved PTAs exceeding 80% for certain EC levels. CONCLUSION:  The study demonstrates the benefits of MIDD using oDox + E as a motivating example. A population pharmacokinetic model was developed for the total and unbound concentration in plasma of docetaxel after administration of IV docetaxel and oDox + E. The model was used to simulate oDox + E dose regimens which were compared to the current standard of care IV docetaxel regimen. A GO / NO-GO framework was applied to determine whether oDox + E should progress to the next phase of drug development and whether any conditions should apply. A two or three-dose regimen of oDox + E at 600 mg was able to achieve non-inferior pharmacokinetic exposure to current standard of care IV docetaxel in simulations. A Conditional GO decision was made based on this result and further quantification of the "effective concentration" would improve the ability to optimise the dose regimen.

Oral paclitaxel and encequidar in patients with breast cancer: a pharmacokinetic, safety, and antitumor activity study.

Background: Paclitaxel is widely used for the treatment of metastatic breast cancer (MBC). However, it has a low oral bioavailability due to gut extrusion caused by P-glycoprotein (P-gp). Oral paclitaxel (oPAC) may be more convenient, less resource-intensive, and more tolerable than its intravenous form. Encequidar (E) is a first-in-class, minimally absorbed, gut-specific oral P-gp inhibitor that facilitates the oral absorption of paclitaxel. Objectives: To investigate the pharmacokinetics (PK), overall response rate (ORR), and safety of weekly oral paclitaxel with encequidar (oPAC + E) in patients with advanced breast cancer. Design: This is a multicenter, single-arm, open-label study in six medical centers in Taiwan. Methods: Patients with advanced breast cancer were administered 205 mg/m2 oPAC and 12.9 mg E for 3 consecutive days weekly for up to 16 weeks. Plasma samples were collected at weeks 1 and 4. PK, ORR, and safety were evaluated. Results: In all, 28 patients were enrolled; 27 had MBC; 23 had prior chemotherapy; and 14 had ⩾2 lines of prior chemotherapy. PK were evaluable in 25 patients. Plasma paclitaxel area under the curve (AUC)(0-52 h) at week 1 (3419 ± 1475 ng h/ml) and week 4 (3224 ± 1150 ng h/ml) were equivalent. Best overall response in 28 evaluable patients was partial response (PR) in 11 (39.3%), 13 (46.4%) stable disease (SD), and 1 (3.6%) with progressive disease (PD). No patient achieved complete response (CR). The clinical benefit rate (CR + PR + SD) was 85.7%. Major adverse events among the 28 treated patients were grade 3 neutropenia (25%), grade 4 neutropenia (18%), with febrile neutropenia in 4%, and grade 3 diarrhea (4%). No treatment-related deaths occurred. Grade 2 peripheral neuropathy occurred in 1 (4%) patient and grade 3 peripheral neuropathy in 1 (4%) patient. Conclusions: oPAC + E produced a consistent therapeutic plasma paclitaxel exposure during treatment. There was a high rate of radiologically assessed clinical benefit, and a low rate of neurotoxicity which may provide advantages over IV paclitaxel. Registration: ClinicalTrials.gov Identifier: NCT03165955.

Topical Tirbanibulin, a Dual Src Kinase and Tubulin Polymerization Inhibitor, for the Treatment of Plaque-Type Psoriasis: Phase I Results.

Plaque-type psoriasis is a common skin disorder. Tirbanibulin (KX01) is a new Src kinase inhibitor with potent antiproliferative activity against keratinocytes and has been approved for treatment of actinic keratosis. This Phase I study investigates the safety and activity of KX01 ointment in patients with plaque-type psoriasis. We recruited 28 patients from two medical centers in Taiwan. This study was performed in four stages. Double-blind treatments were randomized in stages I (KX01 0.01% + placebo, two rounds of two-week treatment) and II (KX01 0.1% + placebo, four weeks) and open-labelled in stages III (KX01 1%, five days) and IV (KX01 1%, five days weekly for four weeks). The safety, tolerability, KX01 concentration, target area score, physician global assessment, and disease relapse were determined. Most treatment-emergent adverse events were mild-to-moderate application site reactions. Three (50.0%) subjects from the stage IV group showed ≥50% reduction in the target area score (TAS50), while two subjects (33.3%) showed a clinically meaningful improvement in the physician global assessment score. KX01 0.01%, 0.1%, and 1% were safe and well-tolerated. KX01 1% at four weeks showed a promising activity for the treatment of plaque-type psoriasis.

A dose regimen-finding study to evaluate the safety, tolerability, pharmacokinetics, and activity of oratecan in subjects with advanced malignancies.

PURPOSE: Irinotecan is a commonly used chemotherapeutic in solid tumor malignancies. Oratecan is an investigational product comprised of encequidar methanesulfonate, a novel minimally absorbed P-glycoprotein pump inhibitor, and irinotecan. This study sought to determine the maximum tolerated dose (MTD) of oratecan in patients with advanced malignancies. METHODS: Using a "3 + 3″ dose-escalation design, patients were treated with oratecan on day 1 every 21 days. The irinotecan dose was escalated from 20 to 320 mg/m2. The encequidar methanesulfonate dose was fixed at 15 mg (12.9 mg free base). PK sampling for irinotecan, encequidar and its major metabolites was performed following a single dose of oratecan during cycle 1. Patients were treated until disease progression or unacceptable toxicity. RESULTS: Thirty-five patients were treated. The MTD was determined to be 280 mg/m2 every 21 days. Irinotecan and SN-38 plasma concentration-time profile showed that irinotecan exposure increased with dose and followed biexponential decay. Nine of 17 patients at oratecan dose levels 200 mg/m2 and above had SN-38 exposures comparable to those with intravenous irinotecan at standard dosing. None of the 35 patients achieved a radiologic response, ten patients had SD for > 8 weeks; the median progression-free survival for all treated patients was 9 weeks (95% CI 8.6-13.9). CONCLUSIONS: The MTD of oratecan was encequidar methanesulfonate 15 mg plus irinotecan 280 mg/m2. Exposure for irinotecan and SN-38 increased with increased dose. Potential antitumor activity was observed at the 280 and 320 mg/m2 dose levels. The safety profile of oratecan was comparable to that of intravenous irinotecan.

A phase Ib study of Oraxol (oral paclitaxel and encequidar) in patients with advanced malignancies.

PURPOSE: Oraxol is an oral formulation of paclitaxel administered with a novel, minimally absorbed P-glycoprotein inhibitor encequidar (HM30181A). This phase Ib study was conducted to determine the maximum-tolerated dose (MTD) of Oraxol administered at a fixed dose for up to 5 consecutive days in patients with advanced malignancies. METHODS: Part 1 of this study utilized a 3 + 3 dose-escalation design to determine the MTD of oral paclitaxel 270 mg plus oral encequidar 15 mg administered daily. Dose escalation was achieved by increasing the number of consecutive dosing days per week (from 2 to 5 days per week). Dosing occurred for 3 consecutive weeks out of a 4-week cycle. Part 2 treated additional patients at the MTD to determine tolerability and recommended phase II dose (RP2D). Adverse events, tumor responses, and pharmacokinetic profiles were assessed. RESULTS: A total of 34 patients (n = 24 in Part 1, n = 10 in Part 2) received treatment. The MTD of Oraxol was determined to be 270 mg daily × 5 days per week per protocol definition and this was declared the RP2D. The most common treatment-related adverse events were fatigue, neutropenia, and nausea/vomiting. Hypersensitivity-type reactions were not observed. Of the 28 patients evaluable for response, 2 (7.1%) achieved partial response and 18 (64.3%) achieved stable disease. Pharmacokinetic analysis showed rapid absorption of paclitaxel when administered orally following encequidar. Paclitaxel daily exposure was comparable following 2-5 days dose levels. CONCLUSION: The oral administration of encequidar with paclitaxel was safe, achieved clinically relevant paclitaxel levels, and showed evidence of anti-tumor activity.

Population pharmacokinetics for oral paclitaxel in patients with advanced/metastatic solid tumors.

Oraxol consists of an oral dosage form of the chemotherapeutic agent paclitaxel administered with a novel P-glycoprotein inhibitor encequidar methanesulfonate monohydrate (formerly named HM30181A), which allows oral treatment of cancers that would otherwise be treated with intravenous paclitaxel. Here we describe the population pharmacokinetics (popPK) analyses for oral paclitaxel in patients with advanced/metastatic solid tumors to characterize pharmacokinetic (PK) profiles and quantify sources of PK variability. The best fit popPK model for oral paclitaxel, based on data from seven clinical studies (197 patients with advanced/metastatic solid tumors), involves a linear two-compartment structural model containing first-order absorption with a short lag time and first-order elimination as well as a log additive error. In this popPK model, lower population estimates of central volume for Asian patients versus Caucasian patients did not translate into clinical meaningful differences in oral paclitaxel exposure. Age, sex, body weight or surface area, mild hepatic impairment, and mild to moderate renal impairment had no clinically meaningful effects on the systemic exposure of oral paclitaxel. Simulations were performed on clinical therapeutic dose (oral paclitaxel 205 mg/m2 once daily ×3 days per week) to predict exposure of oral paclitaxel and to support treatment benefits observed in a pivotal phase III trial.

Oral paclitaxel with encequidar compared to intravenous paclitaxel in patients with advanced cancer: A randomised crossover pharmacokinetic study.

AIMS: Paclitaxel is a widely used anti-neoplastic agent but has low oral bioavailability due to gut extrusion by P-glycoprotein (P-gp). Oral paclitaxel could be more convenient, less resource intensive, and more tolerable than intravenous administration. Encequidar (HM30181A) is a novel, minimally absorbed gut-specific P-gp inhibitor. We tested whether administration of oral paclitaxel with encequidar (oPac+E) achieved comparable AUC to intravenous paclitaxel (IVP) 80 mg/m2 . METHODS: We conducted a multi-centre randomised crossover study with two treatment periods. Patients (pts) with advanced cancer received either oral paclitaxel 615 mg/m2 divided over 3 days and encequidar 15 mg orally 1 hour prior, followed by IVP 80 mg/m2 , or the reverse sequence. PK blood samples were taken up to Day 9 for oPac+E and Day 5 for IVP. RESULTS: Forty-two patients were enrolled; 35 completed both treatment periods. AUC0-∞ was 5033.5 ± 1401.1 ng.h/mL for oPac+E and 5595.9 ± 1264.1 ng.h/mL with IVP. The geometric mean ratio (GMR) for AUC was 89.50% (90% CI 83.89-95.50). Mean absolute bioavailability of oPac+E was 12% (CV% = 23%). PK parameters did not change meaningfully after 4 weeks administration of oPac+E in an extension study. G3 treatment-emergent adverse events occurred in seven (18%) pts with oPac+E and two (5%) with IVP. Seventy-five per cent of patients preferred oPac+E over IVP. CONCLUSIONS: GMR for AUC was within the predefined acceptable range of 80-125% for demonstrating equivalence. oPac+E is tolerable and there is no evidence of P-gp induction with repeat administration. With further study, oPac+E could be an alternative to IVP.

Intrapleural minocycline pleurodesis for the treatment of primary spontaneous pneumothorax.

PURPOSE OF REVIEW: The role of chemical pleurodesis in the treatment of primary spontaneous pneumothorax remains unclear. According to current practice guidelines, chemical pleurodesis is reserved for patients who are unable or unwilling to have surgery. Some recent studies showed that intrapleural minocycline pleurodesis could decrease the rate of pneumothorax recurrence, when used either as the initial treatment for simple pneumothorax after successful aspiration and drainage or as an adjuvant treatment for complicated or recurrent pneumothorax following thoracoscopic surgery. The purpose of this review is to discuss the current available evidence on intrapleural minocycline pleurodesis for the treatment of primary spontaneous pneumothorax. RECENT FINDINGS: In a recently published prospective, randomized controlled trial, additional minocycline pleurodesis following simple aspiration and drainage was a well tolerated and more effective initial treatment for a first episode of primary spontaneous pneumothorax than simple aspiration and drainage alone. Other prospective, randomized controlled trials showed that additional minocycline pleurodesis after thoracoscopic treatment was a well tolerated and convenient procedure which can reduce the rate of ipsilateral recurrence of primary spontaneous pneumothorax. SUMMARY: Intrapleural minocycline pleurodesis can be considered an adjunct to standard treatment of primary spontaneous pneumothorax, after either simple aspiration and drainage or after thoracoscopic surgery.

Simple aspiration and drainage and intrapleural minocycline pleurodesis versus simple aspiration and drainage for the initial treatment of primary spontaneous pneumothorax: an open-label, parallel-group, prospective, randomised, controlled trial.

BACKGROUND: Simple aspiration and drainage is a standard initial treatment for primary spontaneous pneumothorax, but the rate of pneumothorax recurrence is substantial. We investigated whether additional minocycline pleurodesis after simple aspiration and drainage reduces the rate of recurrence. METHODS: In our open-label, parallel-group, prospective, randomised, controlled trial at two hospitals in Taiwan, patients were aged 15-40 years and had a first episode of primary spontaneous pneumothorax with a rim of air greater than 2 cm on chest radiographs, complete lung expansion without air leakage after pigtail catheter drainage, adequate haematological function, and normal renal and hepatic function. After simple aspiration and drainage via a pigtail catheter, patients were randomly assigned (1:1) to receive 300 mg of minocycline pleurodesis or no further treatment (control group). Randomisation was by computer-generated random numbers in sealed envelopes. Our primary endpoint was rate of pneumothorax recurrence at 1 year. This trial is registered with ClinicalTrials.gov (NCT00418392). FINDINGS: Between Dec 31, 2006, and June 30, 2012, 214 patients were randomly assigned-106 to the minocycline group and 108 to the control group (intention-to-treat population). Treatment was unsuccessful within 7 days of randomisation in 14 patients in the minocycline group and 20 patients in the control group. At 1 year, pneumothoraces had recurred in 31 of 106 (29·2%) patients in the minocycline group compared with 53 of 108 (49·1%) in the control group (p=0·003). We noted no procedure-related complications in either group. INTERPRETATION: Simple aspiration and drainage followed by minocycline pleurodesis is a safe and more effective treatment for primary spontaneous pneumothorax than is simple aspiration and drainage only. Minocycline pleurodesis should be an adjunct to standard treatment for primary spontaneous pneumothorax. FUNDING: Department of Health and National Science Council, Taiwan.

Pretreatment epidermal growth factor receptor (EGFR) T790M mutation predicts shorter EGFR tyrosine kinase inhibitor response duration in patients with non-small-cell lung cancer.

PURPOSE: Patients with non-small-cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR)-activating mutations have excellent response to EGFR tyrosine kinase inhibitors (TKIs), but T790M mutation accounts for most TKI drug resistance. This study used highly sensitive methods to detect T790M before and after TKI therapy and investigated the association of T790M and its mutation frequencies with clinical outcome. PATIENTS AND METHODS: Direct sequencing, matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and next-generation sequencing (NGS) were used to assess T790M in the following two cohorts of patients with NSCLC: TKI-naive patients (n = 107) and TKI-treated patients (n = 85). Results were correlated with TKI treatment response and survival. RESULTS: MALDI-TOF MS was highly sensitive in detecting and quantifying the frequency of EGFR-activating mutations and T790M (detection limits, 0.4% to 2.2%). MALDI-TOF MS identified more T790M than direct sequencing in TKI-naive patients with NSCLC (27 of 107 patients, 25.2% v three of 107 patients, 2.8%, respectively; P < .001) and in TKI-treated patients (before TKI: 23 of 73 patients, 31.5% v two of 73 patients, 2.7%, respectively; P < .001; and after TKI: 10 of 12 patients, 83.3% v four of 12 patients, 33.3%, respectively; P = .0143). The EGFR mutations and their frequencies were confirmed by NGS. T790M was an independent predictor of decreased progression-free survival (PFS) in patients with NSCLC who received TKI treatment (P < .05, multivariate Cox regression). CONCLUSION: T790M may not be a rare event before or after TKI therapy in patients with NSCLC with EGFR-activating mutations. The pretreatment T790M mutation was associated with shorter PFS with EGFR TKI therapy in patients with NSCLC.

The ability of LCRMP-1 to promote cancer invasion by enhancing filopodia formation is antagonized by CRMP-1.

Metastasis is a predominant cause of death in patients with cancer. It is a complex multistep process that needs to be better understood if we are to develop new approaches to managing tumor metastasis. Tumor cell invasion of the local stroma is suppressed by collapsin response mediator protein-1 (CRMP-1). Recently, we identified a long isoform of CRMP-1 (LCRMP-1), expression of which correlates with cancer cell invasiveness and poor clinical outcome in patients with non-small-cell lung cancer (NSCLC). Here, we report that LCRMP-1 overexpression in noninvasive human cell lines enhanced filopodia formation, cancer cell migration, and invasion via stabilization of actin. This effect required a highly conserved N-terminal region of LCRMP-1 as well as the WASP family verprolin-homologous protein-1/actin nucleation pathway (WAVE-1/actin nucleation pathway). Furthermore, LCRMP-1 appeared to act downstream of Cdc42, a Rho family protein known to be involved in actin rearrangement. In addition, LCRMP-1 associated with CRMP-1, which downregulated cancer cell metastasis by interrupting the association of LCRMP-1 and WAVE-1. Finally, we found that high-level expression of LCRMP-1 and low-level expression of CRMP-1 were associated with lymph node metastasis and poor survival in patients with NSCLC. In sum, we show that LCRMP-1 and CRMP-1 have opposing functions in regulating cancer cell invasion and metastasis and propose that this pathway may serve as a potential anticancer target.

Economic benefits of sponsored clinical trials on pharmaceutical expenditures at a medical center in Taiwan.

Concerns exist regarding the additional cost of patient care when patients are enrolled in clinical trials at hospitals. To assess the avoidance of drug costs by conducting sponsored clinical trials, a retrospective analysis evaluating drug cost avoidance in all sponsored clinical trials was conducted in 2008 at the most prominent medical center in Taiwan. The National Health Insurance (NHI) reimbursement prices of either the investigated drugs or the standardized drug therapy for each specific disease were used to calculate the cost avoidance. Drug cost avoidance from sponsored clinical trials per year, per trial, per patient, in different therapeutic areas, and in different phases was analyzed. Three quarters of the cost avoidance in drug expenditures from 194 sponsored clinical trials were estimated. All cost values are in US Dollars. Around $11.2 million was avoided at the center in 2008. The average value of cost avoidance was $58,000/trial-year or $3,900/participant-year. The early-phase trials and phase III trials accounted for 25% and 56% of all trials, respectively, while they constituted 32% and 49% of the total costs avoided, respectively. The most frequently conducted and highest cost-avoiding trials were those for antineoplastic agents, especially targeted therapy which accounted for 85% of the total cost avoidance of anti-cancer trials. This study demonstrates the profoundly positive economic impact on the healthcare system in Taiwan by sponsored clinical trials. To understand the trend of economic benefits of the trials on pharmaceutical expenditure, it would be important to analyze the cost avoidance of trials regularly in an institution.

p53 controls cancer cell invasion by inducing the MDM2-mediated degradation of Slug.

The tumour suppressor p53 is known to prevent cancer progression by inhibiting proliferation and inducing apoptosis of tumour cells. Slug, an invasion promoter, exerts its effects by repressing E-cadherin transcription. Here we show that wild-type p53 (wtp53) suppresses cancer invasion by inducing Slug degradation, whereas mutant p53 may stabilize Slug protein. In non-small-cell lung cancer (NSCLC), mutation of p53 correlates with low MDM2, high Slug and low E-cadherin expression. This expression profile is associated with poor overall survival and short metastasis-free survival in patients with NSCLC. wtp53 upregulates MDM2 and forms a wtp53-MDM2-Slug complex that facilitates MDM2-mediated Slug degradation. Downregulation of Slug by wtp53 or MDM2 enhances E-cadherin expression and represses cancer cell invasiveness. In contrast, mutant p53 inactivates Slug degradation and leads to Slug accumulation and increased cancer cell invasiveness. Our findings indicate that wtp53 and p53 mutants may differentially control cancer invasion and metastasis through the p53-MDM2-Slug pathway.

MicroRNA signature predicts survival and relapse in lung cancer.

We investigated whether microRNA expression profiles can predict clinical outcome of NSCLC patients. Using real-time RT-PCR, we obtained microRNA expressions in 112 NSCLC patients, which were divided into the training and testing sets. Using Cox regression and risk-score analysis, we identified a five-microRNA signature for the prediction of treatment outcome of NSCLC in the training set. This microRNA signature was validated by the testing set and an independent cohort. Patients with high-risk scores in their microRNA signatures had poor overall and disease-free survivals compared to the low-risk-score patients. This microRNA signature is an independent predictor of the cancer relapse and survival of NSCLC patients.

TREM-1 expression in tumor-associated macrophages and clinical outcome in lung cancer.

RATIONALE: Triggering receptor expressed on myeloid cells (TREM)-1 is a molecule crucial for the triggering and amplification of inflammatory response and a new biomarker for sepsis. Tumor-associated macrophages and inflammation in the tumor microenvironment are also involved in cancer progression. OBJECTIVES: To determine the role of TREM-1 in tumor-associated macrophage and cancer progression. METHODS: Using ELISA and Western blot, we measured soluble TREM-1 levels in 65 pleural effusions of various etiologies. We evaluated TREM-1-positive cells by immunocytochemistry in malignant pleural effusion and in lung tumor versus adjacent normal tissue in surgical specimens from 68 patients with non-small cell lung cancer (NSCLC). TREM-1 expression was correlated with patient survival. TREM-1 expression in primary isolated peripheral blood macrophages cocultured with lung cancer cell lines was determined by quantitative real-time reverse transcriptase-polymerase chain reaction. MEASUREMENTS AND MAIN RESULTS: Soluble TREM-1 and tumor-associated macrophage TREM-1 expression was increased in malignant pleural effusions in patients with NSCLC. Lung cancer cells could directly up-regulate TREM-1 and proinflammatory cytokine (tumor necrosis factor-alpha, IL-1beta) expression in primary isolated peripheral blood macrophages in coculture experiments. Increased TREM-1-positive tumor-associated macrophages in tumor tissue of patients with NSCLC were associated with reduced disease-free (P = 0.011) and overall survival (P = 0.004). Multivariate Cox regression analysis indicated that TREM-1 was an independent predictor of patient survival (hazard ratio, 2.72; 95% confidence interval, 1.33-5.57; P = 0.006). CONCLUSIONS: Cancer cells can directly up-regulate TREM-1 expression in patients' macrophages. TREM-1 expression in tumor-associated macrophages is associated with cancer recurrence and poor survival of patients with NSCLC. TREM-1 and the inflammatory response may play an important role in cancer progression.

Targeting neuropilin 1 as an antitumor strategy in lung cancer.

PURPOSE: Neuropilin 1 (NRP1) is a mediator of lung branching and angiogenesis in embryonic development and angiogenesis in cancer. The role of NRP1 in cancer progression is not fully elucidated. We investigated the role of NRP1 in cancer invasion and tumor angiogenesis, its signaling pathways, prognostic significance, and therapeutic implications. EXPERIMENTAL DESIGN: Sixty patients with non-small cell lung cancer (NSCLC) were studied. NRP1 mRNA expression was measured using real-time quantitative reverse-transcription PCR. NRP1 and cancer cell invasion, angiogenesis, and signaling pathways were studied using NRP1 stimulation by vascular endothelial growth factor 165 (VEGF(165)) and NRP1 inhibition by small interfering RNAs (siRNA), soluble NRP1 (sNRP1), and NRP1-inhibition peptides. The NRP1-inhibition peptides were identified using a phage display peptide library. RESULTS: NSCLC patients with high expression of NRP1 had shorter disease-free (P = 0.0162) and overall survival (P = 0.0164; log-rank test). Multivariate analyses showed NRP1 is an independent prognostic factor in overall (HR, 2.37, 95% CI = 1.15 to 4.9, P = 0.0196) and disease-free survival [hazard ratio (HR), 2.38; 95% confidence interval (95% CI), 1.15-4.91; P = 0.0195] of NSCLC patients. Knockdown of NRP1 suppressed cancer cell migration, invasion, filopodia formation, tumorigenesis, angiogenesis, and in vivo metastasis. NRP1 signaling pathways involved VEGF receptor 2 and phosphoinositide-3-kinase (PI3K) and Akt activation. Two potent synthetic anti-NRP1 peptides, DG1 and DG2, which block NRP1 signaling pathways and suppress tumorigenesis, cancer invasion, and angiogenesis, were identified. CONCLUSIONS: NRP1 is a cancer invasion and angiogenesis enhancer. NRP1 expression is an independent predictor of cancer relapse and poor survival in NSCLC patients. NRP1 plays a critical role in tumorigenesis, cancer invasion, and angiogenesis through VEGF, PI3K, and Akt pathways. NRP1 may have potential as a new therapeutic target in NSCLC.