Erlotinib and bevacizumab have synergistic activity against melanoma

Clinical efficacy and prognosis analysis of treatment regimens for EGFR mutant non-small cell lung cancer and brain metastasis: a retrospective study

BACKGROUND

The aims of the study were to evaluate potential differences among first-line treatment for EGFR mutant (m+) non-small cell lung cancer (NSCLC) patients with brain metastasis in China and to identify the factors influencing survival outcomes.

METHODS

In this retrospective study, 172 EGFRm + patients with advanced NSCLC who received a 1st generation EGFR tyrosine kinase inhibitor (TKI) were divided into 4 groups: A, EGFR-TKI (n = 84); B, EGFR-TKI + pemetrexed + cisplatin/carboplatin chemotherapy (CT) (n = 55); C, EGFR-TKI + bevacizumab (n = 15); and D, EGFR-TKI + pemetrexed + cisplatin/carboplatin CT + bevacizumab (n = 18). Intracranial and extracranial progression-free survival (PFS), the overall survival (OS), objective remission rates (ORRs) and adverse events were analyzed.

RESULTS

Intracranial PFS of groups C + D was longer than for groups A + B (18.9 m vs. 11.0 m, P = 0.027). Extracranial PFS were longer in group B in comparison with group A (13.0 m vs. 11.5 m, P = 0.039) and in groups C + D compared to groups A + B (18.9 m vs. 11.9 m, P = 0.008). Median OS in groups A and B were 27.9 m and 24.4 m, respectively, while groups C and D have not yet achieved median OS. Significant difference was found in intracranial ORR between groups A + B vs. C + D (31.0% vs. 65.2%, P = 0.002). Most patients suffered grade 1-2 treatment-related adverse events, which were relieved soon after symptomatic treatment.

CONCLUSIONS

First-generation EGFR-TKI + bevacizumab treatment outperformed other regimens in EGFRm + NSCLC patients with brain metastasis. The therapy improved the control and delayed progression of intracranial lesions and prolonged survival times.

LAPS score for individualized treatment of advanced EGFR-mutated non-small cell lung cancer receiving EGFR-TKIs with or without bevacizumab

BACKGROUND

To establish a risk stratification score to facilitate individualized treatment for patients with advanced epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC).

METHODS

We enrolled 160 advanced EGFR-mutated NSCLC who received first-generation EGFR-tyrosine kinase inhibitor (EGFR-TKI) with or without bevacizumab. Kaplan-Meier curves were used for survival analysis. Univariate and multivariate analyses were used to identify independent prognostic factors associated with progression-free survival (PFS) and overall survival (OS).

RESULTS

There were 107 patients in EGFR-TKI monotherapy (T group) and 53 patients in EGFR-TKI with bevacizumab (A + T group). The median PFS in the A + T group was significantly longer than that in the T group (p = 0.002). No difference in the median OS between the A + T and T groups (p = 0.721). The multivariate analyses showed that Eastern Cooperative Oncology Group performance status (ECOG PS) and the pre-treatment lactate dehydrogenase-albumin ratio (LAR) were independent prognostic factors for PFS and OS. The LAR-ECOG PS (LAPS) score was constructed by combining the pre-treatment LAR and ECOG PS. We defined ECOG PS 2 and high pre-treatment LAR as a score of 1. Then, patients with a total LAPS score of 0 were categorized as low-risk and those with 1-2 scores were classified as high-risk. For patients in low-risk group, there was no significant difference in PFS, OS, objective response rate (ORR), and disease control rate (DCR) among those who received EGFR-TKI with or without bevacizumab. However, patients in high-risk group had a significant benefit in PFS and DCR when treated with EGFR-TKI plus bevacizumab compared to those who received EGFR-TKI alone.

CONCLUSIONS

Novel LAPS score may help to facilitate individualized treatment of advanced EGFR-mutated NSCLC receiving EGFR-TKI with or without bevacizumab.

Clinical and molecular feature-based nomogram model for predicting benefit from bevacizumab combined with first-generation EGFR-tyrosine kinase inhibitor (TKI) in EGFR-mutant advanced NSCLC

BACKGROUND

The combination of bevacizumab and epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) could prolong progression-free survival (PFS) in patients with EGFR-mutant advanced non-small-cell lung cancer (NSCLC). Our study investigated the clinical and molecular factors that affect the efficacy of first-generation EGFR-TKI with or without bevacizumab and identify the subset of patients who can benefit from combination therapy.

METHODS

Our study included 318 patients with EGFR-mutant locally advanced/advanced NSCLC treated with either first-generation EGFR-TKI combined with bevacizumab (A+T; n = 159) or EGFR-TKI monotherapy (T; n = 159). Two nomogram models to predict PFS and overall survival (OS), respectively, were constructed using two factors that impact EGFR-TKI efficacy: metastatic site and presence of concurrent mutations. The study cohort was stratified into 2 cohorts for training (n = 176) and validation (n = 142) of the nomogram model. Using the median score from the nomogram, the patients were stratified into two groups to analyze their survival outcome.

RESULTS

The A+T group had significantly longer PFS (14.0 vs. 10.5 months; p < 0.001) and OS (37.0 vs. 26.0 months; p = 0.042) than the T group. Among the patients with concurrent mutations in tumor suppressor genes, those in the A+T group had significantly longer PFS and OS than the T group (PFS 14.5 vs. 8.0 months, p < 0.001; OS 39.0 vs. 20.0 months, p = 0.003). The higher scores from the nomograms were associated with the presence of brain/liver/pleural metastasis or concomitant gene mutations, which indicated a higher likelihood of shorter PFS and OS. The validation of the nomogram revealed that patients with lower scores had significantly longer PFS for the T group than those with higher scores (15.0 vs. 9.0 months, p = 0.002), but not for the A+T group (15.9 vs. 13.9 months, p = 0.256).

CONCLUSIONS

Using a nomogram, our study demonstrated that the addition of bevacizumab may enhance the therapeutic effectiveness of EGFR-TKI by overcoming the negative impact of certain clinical and molecular factors on the efficacy of EGFR-TKI.

RTK Inhibitors in Melanoma: From Bench to Bedside

MAPK (mitogen activated protein kinase) and PI3K/AKT (Phosphatidylinositol-3-Kinase and Protein Kinase B) pathways play a key role in melanoma progression and metastasis that are regulated by receptor tyrosine kinases (RTKs). Although RTKs are mutated in a small percentage of melanomas, several receptors were found up regulated/altered in various stages of melanoma initiation, progression, or metastasis. Targeting RTKs remains a significant challenge in melanoma, due to their variable expression across different melanoma stages of progression and among melanoma subtypes that consequently affect response to treatment and disease progression. In this review, we discuss in details the activation mechanism of several key RTKs: type III: c-KIT (mast/stem cell growth factor receptor); type I: EGFR (Epidermal growth factor receptor); type VIII: HGFR (hepatocyte growth factor receptor); type V: VEGFR (Vascular endothelial growth factor), structure variants, the function of their structural domains, and their alteration and its association with melanoma initiation and progression. Furthermore, several RTK inhibitors targeting the same receptor were tested alone or in combination with other therapies, yielding variable responses among different melanoma groups. Here, we classified RTK inhibitors by families and summarized all tested drugs in melanoma indicating the rationale behind the use of these drugs in each melanoma subgroups from preclinical studies to clinical trials with a specific focus on their purpose of treatment, resulted effect, and outcomes.

Bevacizumab combined with apatinib enhances antitumor and anti-angiogenesis effects in a lung cancer model in vitro and in vivo

Angiogenesis is involved in the proliferation and metastasis of solid tumours; hence, it is an attractive therapeutic target. However, most patients who undergo anti-angiogenic drug treatment do not achieve complete tumour regression, resulting in drug resistance. The objective of this research is to explore the therapeutic effect of combining bevacizumab (Bev), an anti-vascular endothelial growth factor (VEGF)-A antibody, with apatinib (Apa), a VEGR receptor (VEGFR)-2-targeting tyrosine kinase inhibitor, in non-small cell lung cancer (NSCLC). In vitro, we assessed the influence which Bev + Apa treatment exerts upon the proliferation as well as apoptosis of Lewis lung carcinoma (LLC) cells in virtue of the 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide as assay as well as Annexin V staining, respectively. For in vivo assessment, we established a tumour-bearing mouse model with LLC cells and investigated the anti-angiogenic and antitumor effects of Bev + Apa by ¹⁸F-FDG PET/CT imaging, immunohistochemistry and TUNEL staining. Bev + Apa treatment significantly inhibited LLC cell growth and proliferation in a larger scale compared to therapy of either of the only agent. Bev + Apa inhibited tumour growth and extended the median survival time of tumour-bearing mice. Mechanistically, Bev + Apa reduced angiogenesis by inhibiting VEGF and VEGFR-2 expression and reducing glucose metabolism in tumour tissues. Thus, Bev and Apa inhibited tumour angiogenesis synergistically, indicating their potential clinical utility for NSCLC treatment.

Targeting PHGDH Upregulation Reduces Glutathione Levels and Resensitizes Resistant NRAS-Mutant Melanoma to MAPK Kinase Inhibition

Melanomas frequently harbor activating NRAS mutations leading to activation of MAPK kinase (MEK) and extracellular signal-regulated kinase 1/2 signaling; however, the clinical efficacy of inhibitors to this pathway is limited by resistance. Tumors rewire metabolic pathways in response to stress signals such as targeted inhibitors and drug resistance, but most therapy-resistant preclinical models are generated in conditions that lack physiological metabolism. We generated human NRAS-mutant melanoma xenografts that were resistant to the MEK inhibitor (MEKi) PD0325901 in vivo. MEKi-resistant cells showed cross-resistance to the structurally distinct MEKi trametinib and elevated extracellular signal-regulated kinase 1/2 phosphorylation and downstream signaling. Additionally, we observed upregulation of the serine synthesis pathway and PHGDH, a key enzyme in this pathway. Suppressing PHGDH in MEKi-resistant cells together with MEKi treatment decreased oxidative stress tolerance and cell proliferation. Together, our data suggest targeting PHGDH as a potential strategy in overcoming MEKi resistance.

Determining the appropriate treatment for different EGFR mutations in non-small cell lung cancer patients

Introduction: Epidermal growth factor receptor (EGFR) mutations occur in a significant fraction of non-small cell lung cancer (NSCLC) patients. Most common activating mutations are in-frame deletion in exon 19 and point mutation in exon 21. EGFR tyrosine kinase inhibitors (TKIs) represent standard of care of EGFR mutated patients bearing common mutations. Therapy for individuals carrying uncommon mutations, such as G719X, L861Q, S768I, is less defined and few options exist for individuals harboring EGFR exon 20 mutations. In all mutated patients, drug resistance remains the most critical clinical problem and new agents and strategies are under investigation.Areas covered: We have reviewed the current status of NSCLC EGFR mutated treatment by analyzing data from preclinical studies, clinical prospective and retrospective trials in order to analyze current and future options for patients harboring different EGFR mutations.Expert opinion: At the present time, available data demonstrated that osimertinib is the best EGFR-TKI for front-line therapy. Other agents, such as dacomitinib, and new drug combinations, such as regimens including anti-angiogenic agents or chemotherapy, demonstrated to significantly prolong progression-free survival or overall survival, representing potential alternative to osimertinib. Many questions remain opened, including best drug sequencing and needing of new therapeutic approaches extending patient survival and cure rate.

The Story of Angiogenesis Inhibitors in Non-small-cell Lung Cancer: The Past, Present, and Future

The treatment of advanced non-small-lung cancer (NSCLC) has steadily evolved over the past 2 decades, and current therapy includes chemoimmunotherapy or targeted therapy with tyrosine kinase inhibitors (TKIs). Angiogenesis inhibitors were first approved in the mid-2000s in combination with chemotherapy for the treatment of NSCLC. The addition of anti-angiogenics to chemotherapy resulted in modest increases in survival when median overall survival was less than 1 year. More recently, the use of anti-angiogenics has fallen out of favor with the advent of checkpoint inhibitors and never-before-seen durable long-term responses. However, we postulate that there is still an important role for anti-angiogenics in this era of targeted therapy and checkpoint inhibitors in the treatment of NSCLC. Preclinical studies have shown that combination blockade of the epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF) pathways leads to synergistic antitumor effects. These results have been replicated in the clinical setting in patients who harbor EGFR mutations, with VEGF inhibitor-TKI dual therapy leading to impressive survival outcomes. Similarly, combination treatment with checkpoint inhibitors and VEGF inhibitors have led to unprecedented survival outcomes in both advanced renal cell cancer as well as NSCLC. In this review, we explore the evolution of anti-angiogenic therapy in advanced NSCLC and discuss the clinical efficacy of angiogenesis inhibitors in combination with chemotherapy, TKI therapy, and checkpoint inhibitors.

EGFR-TKIs plus bevacizumab demonstrated survival benefit than EGFR-TKIs alone in patients with EGFR-mutant NSCLC and multiple brain metastases

INTRODUCTION

Previous studies suggested that epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKIs) plus bevacizumab could significantly prolong progression-free survival (PFS) than EGFR-TKI alone as first-line setting for patients with EGFR-mutant non-small-cell lung cancer (NSCLC). However, whether this combination could benefit patients with multiple brain metastases (BrMs) remains undetermined.

METHODS

A total of 208 patients with EGFR-mutant NSCLC and multiple BrM (number >3, at least one of lesions was measurable) were retrospectively identified. Kaplan-Meier curves with two-sided log-rank tests and Cox proportional hazards model with calculated hazard ratios and 95% confidence intervals were used to determine the survival difference.

RESULTS

Of all patients, 149 patients received EGFR-TKIs monotherapy and 59 received EGFR-TKIs plus bevacizumab as first-line setting. EGFR-TKIs plus bevacizumab was associated with a significantly higher intracranial objective response rate (ORR, 66.1% vs. 41.6%, P = 0.001), systemic ORR (74.6% vs. 57.1%, P = 0.019), longer intracranial PFS (14.0 vs. 8.2 months; P < 0.001) and systemic PFS (14.4 vs. 9.0 months; P < 0.001). Importantly, addition of bevacizumab also had a significantly longer overall survival (OS, 29.6 vs. 21.7 months; P < 0.001). Multivariate analysis consistently revealed that addition of bevacizumab was independently associated with prolonged intracranial and systemic PFS, and OS. No unexpected serious adverse effects were observed.

CONCLUSIONS

EGFR-TKIs plus bevacizumab prolonged not only PFS but also OS in patients with EGFR-mutant NSCLC and multiple BrMs when compared with EGFR-TKIs alone, indicating that this combination could be an alternative therapeutic option for those patients.

Bevacizumab and erlotinib versus bevacizumab for colorectal cancer treatment: systematic review and meta-analysis

Background Improving the survival of patients diagnosed with metastatic colorectal cancer requires the use of chemotherapy to be managed with minimum adverse effects. Randomized control trials (RCTs) have shown promising results with a combination of bevacizumab and erlotinib to block two important tumor growth pathways, namely vascular endothelial growth factor and epidermal growth factor receptor. Aim of the Review We aimed to examine the efficacy and safety of the combination of bevacizumab and erlotinib with bevacizumab alone in the maintenance treatment of metastatic colorectal cancer, by examining PFS, OS, overall response rate (ORR), and toxicity. This study performed a systematic review meta-analysis using existing randomized clinical trial. Methods Randomized controlled trials were systematically reviewed from PubMed, Cochrane library, SCOPUS, CRD, and Google scholar databases. After evaluating the quality of studies through the Cochrane checklist, data of the relevant studies were extracted. This meta-analysis included outcomes of overall survival, progression-free survival of the disease through the hazard ratio, and the upper and lower confidence intervals for the third and fourth degree side effects of relative risk. To perform the meta-analysis for both types of survival, two fixed and random effect models were used. Results A total of three trials, providing data of 682 patients who received maintenance treatment, were included in this meta-analysis. Conclusion The combination of bevacizumab and erlotinib significantly increased the overall survival compared to using bevacizumab alone [HR = 0.78, 95% CI 0.66-0.93]. This combination, effectively increased progression-free survival [HR = 0.81, 95% CI 0.7-0.93] too. The side effects of diarrhea and grade III rash were more frequent in the group administered bevacizumab plus erlotinib. The combination of bevacizumab and erlotinib, in the maintenance treatment of metastatic colorectal cancer, significantly improved the overall survival and progression-free survival of patients, and the resulting side effects were easily treatable.

Synergistic Anticancer Effect of a Combination of Paclitaxel and 5-Demethylnobiletin Against Lung Cancer Cell Line In Vitro and In Vivo

Lung cancer remains a highly prevalent disease and a leading cause of cancer-related deaths worldwide. Currently, exploring antitumor drugs derived from herbs used in traditional Chinese medicine is increasingly becoming an attractive area of research. Paclitaxel (PTX), a highly effective chemotherapeutic drug, is widely used for treating different cancers; however, the clinical use of PTX is dose limited because of its adverse side effects. Chemotherapeutic agents are being developed to enhance the anticancer activity of PTX, particularly for use in combination therapy. 5-Demethylnobiletin (5-DMN), a natural, active compound isolated from orange peel, has been reported to induce apoptosis in several cancer cell lines. In this study, we tested the synergistic anticancer antiproliferative effects of combinations of PTX and 5-DMN on CL1-5 lung cancer cells through the MTT and propidium iodide assays. After low-dose combination treatments (PTX and 5-DMN), a reduction in cell viability and a concomitant increase in apoptosis were observed in the CL1-5 cells. We propose that 5-DMN cooperates with PTX to induce apoptosis via the caspase pathway (by modulating caspase-3, caspase-8, and caspase-9 activities). Furthermore, we observed that the combination treatment significantly suppressed tumor growth in the nude mouse xenograft model. The results suggest that the synergistic effects of PTX and 5-DMN in lung cancer cells deserve particular attention and indicate the possibility of developing additional new strategies for treating lung cancer.

Gefitinib or lapatinib with foretinib synergistically induce a cytotoxic effect in melanoma cell lines

Melanoma is an aggressive cancer type with a high mortality rate and an elevated resistance to conventional treatment. Recently, promising new tools for anti-melanoma targeted therapy have emerged including inhibitors directed against frequently overexpressed receptors of growth factors implicated in the progression of this cancer. The ineffectiveness of single-targeted therapy prompted us to study the efficacy of treatment with a combination of foretinib, a MET (hepatocyte growth factor receptor) inhibitor, and gefitinib or lapatinib, EGFR (epidermal growth factor receptor) inhibitors. We observed a synergistic cytotoxic effect for the combination of foretinib and lapatinib on the viability and proliferation of the examined melanoma cell lines. This combination of inhibitors significantly decreased Akt and Erk phosphorylation, while the drugs used independently were insufficient. Additionally, after treatment with pairs of inhibitors, cells became larger, with more pronounced stress fibers and abnormally shaped nuclei. We also noticed the appearance of polyploid cells and massive enrichment in the G2/M phase. Therefore, combination treatment was much more effective against melanoma cells than a single-targeted approach. Based on our results, we conclude that both EGFR and MET receptors might be effective targets in melanoma therapy. However, variation in their levels in patients should be taken into consideration.

Phase II Trial of Adjuvant Immunotherapy with Autologous Tumor-derived Gp96 Vaccination in Patients with Gastric Cancer

Background/Aims: Autologous, tumor-derived, heat shock protein gp96 peptide complexes have antitumor potential. We conducted the first Phase II trial to evaluate the safety and efficacy of gp96 vaccination in adjuvant settings for patients with gastric cancer.

Methods: We enrolled 73 consecutive patients from October 2012 to December 2015. Thirty-eight patients received gp96 vaccination plus chemotherapy and 35 received chemotherapy alone. The primary endpoints were disease-free survival (DFS) and toxicity. The secondary endpoints were overall survival (OS) and tumor-specific immune responses.

Results: There were comparable baseline characteristics between the two groups. Tumor-specific immune responses increased significantly after gp96 vaccination. gp96 vaccination plus chemotherapy was well tolerated and there were no gp96-related serious adverse events. Patients who received gp96 vaccination had improved DFS compared with those who did not [p = 0.045; hazard ratio (HR): 0.47; 95% confidence interval (CI): 0.23-0.96]. The 2-year OS rates were 81.9% and 67.9% for the gp96 vaccination and chemotherapy alone group, respectively (p = 0.123; HR: 0.42; 95% CI: 0.15-1.24).

Conclusion: gp96 vaccination elicits tumor-specific immune responses and can be safely used in adjuvant settings combined with chemotherapy. Patients with less-aggressive diseases might benefit from gp96 therapy.

A phase II clinical study of combining FOLFIRI and bevacizumab plus erlotinib in 2nd-line chemotherapy for patients with metastatic colorectal cancer

We conducted an open-label single-arm phase II study by combining irinotecan (FOLFIRI) and bevacizumab (BV) plus erlotinib (ER) in 2nd-line chemotherapy for patients with metastatic colorectal cancer (mCRC).Eligible mCRC patients received 1st-line standard chemotherapy but still had progressive disease. They were given FOLFIRI plus BV at 2.5 mg/kg on day 1 per 2-week cycle, and daily 150 mg ER. The primary endpoint is progression-free survival (PFS).A total of 122 patients enrolled in the study. Among them, 55.7% were male patients and median age was 58.4 years (29-72 years). Median PFS was 7.1 months (95% CI 4.3-10.2). Median overall survival (OS) was 13.5 months (95% CI 9.7-16.4). No patients had complete responses, 24 patients had partial response (19.6%) and 59 had stable disease (48.4%). The most frequent adverse event (AE) was rash, with 66 patients (54.1%) had grade 3/4 rash. Other frequent grade 3/4 AEs were fatigue (n = 36, 29.5%), bleeding (n = 31, 25.4%), neutropenia (n = 23, 18.9%), and platelets (n = 14, 11.5%).Combining FOLFIRI and BV plus ER in 2nd-line chemotherapy is efficient to treat mCRC patients with acceptable safety.

Bevacizumab counteracts VEGF-dependent resistance to erlotinib in an EGFR-mutated NSCLC xenograft model

Erlotinib, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), shows superior efficacy in patients with non-small cell lung cancer (NSCLC) harboring activating EGFR mutations (EGFR Mut⁺). However, almost all tumors eventually develop resistance to erlotinib. Recently, the Phase II JO25567 study reported significant prolongation of progression-free survival (PFS) by erlotinib plus bevacizumab combination compared with erlotinib in EGFR Mut⁺ NSCLC. Herein, we established a preclinical model which became refractory to erlotinib after long-term administration and elucidated the mode of action of this combination. In this model, tumor regrowth occurred after remarkable shrinkage by erlotinib; regrowth was successfully inhibited by erlotinib plus bevacizumab. Tumor vascular endothelial growth factor (VEGF) was greatly reduced by erlotinib in the erlotinib-sensitive phase but significantly increased in the erlotinib-refractory phase despite continued treatment with erlotinib. Although EGFR phosphorylation remained suppressed in the erlotinib-refractory phase, phosphorylated extracellular signal-regulated kinase (pERK), phosphorylated AKT, and phosphorylated signal transducer and activator of transcription 3 (pSTAT3) were markedly higher than in the erlotinib-sensitive phase; among these, pERK was suppressed by erlotinib plus bevacizumab. MVD was decreased significantly more with erlotinib plus bevacizumab than with each drug alone. In conclusion, the erlotinib plus bevacizumab combination demonstrated promising efficacy in the B901L xenograft model of EGFR Mut⁺ NSCLC. Re-induction of VEGF and subsequent direct or indirect VEGF-dependent tumor growth was suggested as a major mechanism of erlotinib resistance, and erlotinib plus bevacizumab achieved remarkably prolonged antitumor activity in this model.

Survival Benefit and Safety of Bevacizumab in Combination with Erlotinib as Maintenance Therapy in Patients with Metastatic Colorectal Cancer: A Meta-Analysis

BACKGROUND

Recently, the need for maintenance chemotherapy arose as a result of the significantly improved survival of patients with metastatic colorectal cancer (mCRC) without increasing adverse events. Currently used maintenance regimens are fluoropyrimidines, bevacizumab, and the combination of fluoropyrimidine with bevacizumab. A new combination with bevacizumab and erlotinib, a tyrosine kinase inhibitor of the epithelial growth factor receptor, has shown synergistic effects in preclinical tests and promising results in some clinical trials. Whether bevacizumab combined with erlotinib vs. bevacizumab alone as maintenance therapy will further improve the clinical outcomes in patients with mCRC is controversial. We conducted this meta-analysis to compare the survival benefit and safety of these two regimens in patients with mCRC.

METHODS

We searched PubMed, EMBASE, and the Central Registry of Controlled Trials of the Cochrane Library up to August 2016. We also searched the Proceedings of the American Society of Clinical Oncology (1986 to August 2016). Abstracts were manually searched to identify relevant trials. A total of three randomized controlled trials with 682 patients met the inclusion criteria.

RESULTS

Our results demonstrated that bevacizumab combined with erlotinib significantly improved overall survival (hazard ratio 0.78; 95 % confidence interval 0.66-0.93; p = 0.006) and progression-free survival (hazard ratio 0.79; 95 % confidence interval 0.68-0.92; p = 0.002). Significantly more grade 3 rash, diarrhea, infection total, and fatigue were observed in the bevacizumab combined with erlotinib arm, which were controllable and reversible.

CONCLUSIONS

Based on current evidence, the addition of erlotinib to bevacizumab as maintenance therapy significantly increases overall survival and progression-free survival with an increased but manageable toxicity in patients with mCRC. It should be considered as a treatment option for these patients under the premise of a reasonable selection of the target population.

Potential therapeutic targets of epithelial-mesenchymal transition in melanoma

Melanoma is a cutaneous neoplastic growth of melanocytes with great potential to invade and metastasize, especially when not treated early and effectively. Epithelial-mesenchymal transition (EMT) is the process by which melanocytes lose their epithelial characteristics and acquire mesenchymal phenotypes. Mesenchymal protein expression increases the motility, invasiveness, and metastatic potential of melanoma. Many pathways play a role in promotion of mesenchymal protein expression including RAS/RAF/MEK/ERK, PI3K/AKT/mTOR, Wnt/β-catenin, and several others. Downstream effectors of these pathways induce expression of EMT transcription factors including Snail, Slug, Twist, and Zeb that promote repression of epithelial and induction of mesenchymal character. Emerging research has demonstrated that a variety of small molecule inhibitors as well as phytochemicals can influence the progression of EMT and may even reverse the process, inducing re-expression of epithelial markers. Phytochemicals are of particular interest as supplementary treatment options because of their relatively low toxicities and anti-EMT properties. Modulation of EMT signaling pathways using synthetic small molecules and phytochemicals is a potential therapeutic strategy for reducing the aggressive progression of metastatic melanoma. In this review, we discuss the emerging pathways and transcription factor targets that regulate EMT and evaluate potential synthetic small molecules and naturally occurring compounds that may reduce metastatic melanoma progression.

Erlotinib-based targeted dual agent versus erlotinib alone in previously treated advanced non-small-cell lung cancer: a meta-analysis of 13 randomized controlled trials

OBJECTIVES

To compare the effects of an erlotinib-based targeted dual agent with erlotinib alone in previously treated patients with advanced non-small lung cancer (NSCLC).

PATIENTS AND METHODS

The PubMed and Embase databases and the Cochrane Central Register of Controlled Trials were searched for publications between January 2005 and March 2016. Hazard ratios (HRs) with their 95% confidence intervals (CIs), or data for calculating HRs with 95% CIs were derived. Overall survival (OS), progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and toxicity were assessed.

RESULTS

Thirteen trials with a total of 4509 patients were included in this meta-analysis. Compared with erlotinib alone, combination therapy showed no improvement in OS (HR = 0.95; 95% CI, 0.89-1.02; P = .132) though significantly prolonged PFS (HR = 0.82; 95% CI, 0.75-0.90; P < .001). Combination therapy significantly increased ORR (RR = 1.32; 95% CI, 1.09-1.60; P = .005) and DCR (RR = 1.26; 95% CI, 1.17-1.36, P < .001). Sub-analysis assessment failed to identify any sub-groups which could benefit from combination therapy in terms of OS. Combination therapy was associated with more grade 3 or higher toxic effects (RR = 1.54; 95% CI, 1.22-1.95; P < .001). Patients treated with combination therapy had more grade 3 or greater fatigue (RR = 1.49; 95% CI, 1.16-1.91; P = .002), but did not develop more diarrhea (RR = 2.02; 95% CI, 0.86-4.77; P = .107) or rash (RR = 1.29, 95% CI, 0.90-1.85; P = .172). This study had limitations about heterogeneities among the included trials, and the analysis was not based on individual patient data.

CONCLUSIONS

Compared with erlotinib alone, the erlotinib-based targeted dual agent showed a minimal magnitude of improvement in PFS but did not improve OS. The role of erlotinib-based combinations in previously treated patients with NSCLC seemed insignificant.

ERBB activation modulates sensitivity to MEK1/2 inhibition in a subset of driver-negative melanoma

Melanomas are characterized by activating “driver” mutations in BRAF, NRAS, KIT, GNAQ, and GNA11. Resultant mitogen-activated protein kinase (MAPK) pathway signaling makes some melanomas susceptible to BRAF (BRAF V600 mutations), MEK1/2 (BRAF V600, L597, fusions; NRAS mutations), or other kinase inhibitors (KIT), respectively. Among driver-negative (“pan-negative”) patients, an unexplained heterogeneity of response to MEK1/2 inhibitors has been observed. Analysis of 16 pan-negative melanoma cell lines revealed that 8 (50%; termed Class I) are sensitive to the MEK1/2 inhibitor, trametinib, similar to BRAF V600E melanomas. A second set (termed Class II) display reduced trametinib sensitivity, paradoxical activation of MEK1/2 and basal activation of ERBBs 1, 2, and 3 (4 lines, 25%). In 3 of these lines, PI3K/AKT and MAPK pathway signaling is abrogated using the ERBB inhibitor, afatinib, and proliferation is even further reduced upon the addition of trametinib. A potential mechanism of ERBB activation in Class II melanomas is minimal expression of the ERK1/2 phosphatase, DUSP4, as ectopic restoration of DUSP4 attenuated ERBB signaling through potential modulation of the ERBB ligand, amphiregulin (AREG). Consistent with these data, immunohistochemical analysis of patient melanomas revealed a trend towards lower overall DUSP4 expression in pan-negative versus BRAF- and NRAS-mutant tumors. This study is the first to demonstrate that differential ERBB activity in pan-negative melanoma may modulate sensitivity to clinically-available MEK1/2 inhibitors and provides rationale for the use of ERBB inhibitors, potentially in combination with MEK1/2 inhibitors, in subsets of this disease.

Efficacy and safety of bevacizumab plus erlotinib versus bevacizumab or erlotinib alone in the treatment of non-small-cell lung cancer: a systematic review and meta-analysis

OBJECTIVES

Bevacizumab and erlotinib inhibit different tumour growth pathways, and both exhibit beneficial effects in the treatment of non-small-cell lung cancer (NSCLC). However, the efficacy of bevacizumab in combination with erlotinib remains controversial. Therefore, we conducted a meta-analysis to compare combination treatment with bevacizumab and erlotinib to bevacizumab or erlotinib monotherapy in the treatment of NSCLC.

METHODS

Randomised controlled trials (RCTs) published in PubMed, Web of Science and EMBASE were systematically reviewed. The main outcome measures included overall survival (OS), progression-free survival (PFS), overall response rate (ORR) and adverse events. Results were expressed as HRs or risk ratios (RRs) with 95% CIs.

RESULTS

5 RCTs involving a total of 1736 patients were included in this meta-analysis. The combination of bevacizumab and erlotinib significantly improved PFS (HR=0.63, 95% CI 0.53 to 0.75; p=0.000) and the ORR (RR=1.91, 95% CI 1.19 to 3.06; p=0.007) in the second-line treatment of NSCLC compared with bevacizumab or erlotinib alone. However, no significant difference in OS was observed between the combination and monotherapy groups (HR=0.96, 95% CI 0.83 to 1.11; p=0.573). A subgroup analysis has shown that the greatest PFS benefit was associated with an age of <65 years(HR=0.74, 95% CI 0.57 to 0.96; p=0.026), Asian/Pacific Islander ethnicity (HR=0.23, 95% CI 0.10 to 0.54; p=0.001), Eastern Cooperative Oncology Group performance status (ECOG PS) 1 (HR=0.82, 95% CI 0.68 to 0.98; p=0.033), stage IIIB or IV disease (HR=0.68, 95% CI 0.57 to 0.82; p=0.000) and no history of smoking (HR=0.48, 95% CI 0.32 to 0.71; p=0.000). The incidence of grade 3/4 adverse events such as rash and diarrhoea was higher in the combination group than in the monotherapy group.

CONCLUSIONS

The addition of bevacizumab to erlotinib can significantly improve PFS and the ORR in the second-line treatment of NSCLC with an acceptable and manageable risk of rash and diarrhoea. Further well-conducted, large-scale trials are needed to validate these findings.

Phase I Trial of Consolidative Radiotherapy with Concurrent Bevacizumab, Erlotinib and Capecitabine for Unresectable Pancreatic Cancer

Purpose

To determine the safety, tolerability and maximum tolerated dose (MTD) of addition of erlotinib to bevacizumab and capecitabine-based definitive chemoradiation (CRT) in unresectable pancreatic cancer.

Methods

Seventeen patients with CT-staged, biopsy-proven unresectable pancreatic cancer were enrolled between 3/2008 and 10/2010. Prior chemotherapy was permitted. Two patients each were enrolled at dose levels (DLs) 1–4 and 9 patients at DL 5. All patients received 50.4 Gy (GTV only) in 28 fractions with concurrent capecitabine, bevacizumab and erlotinib. Dose of each drug was escalated in 5 DLs using the continual reassessment method. Bevacizumab was escalated from 5mg/Kg q2weeks (DLs 1–4) to 10mg/Kg q2weeks (DL 5); daily erlotinib from 100mg/day (DLs 1–2) to 150 mg/Kg (DLs 3–5); and capecitabine from 400mg/m² twice daily on days of radiation (DL 1) to 650mg/m² (DLs 2–3) to 825 mg/m² (DLs 4–5). Reassessment for potential resection was performed 6–8 weeks later.

Results

Sixteen patients received gemcitabine-based chemotherapy prior to CRT. With a median clinical follow-up of 10 months, no grade 3 toxicities were observed in DLs 1–4. Three (33%) patients at DL 5 developed a grade 3 acute toxicity (2 diarrhea, 1 rash). No grade 4 or 5 toxicities were seen. DL 4 was selected as the MTD; therefore, the recommended doses in combination with radiation are: bevacizumab, 5mg/Kg q2weeks; erlotinib, 150 mg/Kg daily; and capecitabine, 825mg/m² BID. Median survival was 17.4 months. Of the five patients who underwent resection, 4 were originally deemed locally advanced and 1 was borderline resectable. Three patients had excellent pathological response (2 complete response and 20% viable tumor) at surgery, and the 2 patients with complete response are still alive at 61 and 67 months of follow up with no local or distant failures.

Conclusions

This chemoradiation regimen at the recommended dose levels is safe and tolerable for patients with unresectable pancreatic cancer and merits further evaluation.

Targeting mutant NRAS signaling pathways in melanoma

Cutaneous melanoma is a devastating form of skin cancer and its incidence is increasing faster than any other preventable cancer in the United States. The mutant NRAS subset of melanoma is more aggressive and associated with poorer outcomes compared to non-NRAS mutant melanoma. The aggressive nature and complex molecular signaling conferred by this transformation has evaded clinically effective treatment options. This review examines the major downstream effectors of NRAS relevant in melanoma and the associated advances made in targeted therapies that focus on these effector pathways. We outline the history of MEK inhibition in mutant NRAS melanoma and recent advances with newer MEK inhibitors. Since MEK inhibitors will likely be optimized when combined with other targeted therapies, we focus on recently identified targets that can be used in combination with MEK inhibitors.

A FAK scaffold inhibitor disrupts FAK and VEGFR-3 signaling and blocks melanoma growth by targeting both tumor and endothelial cells

Melanoma has the highest mortality rate of all skin cancers and a major cause of treatment failure is drug resistance. Tumors heterogeneity requires novel therapeutic strategies and new drugs targeting multiple pathways. One of the new approaches is targeting the scaffolding function of tumor related proteins such as focal adhesion kinase (FAK). FAK is overexpressed in most solid tumors and is involved in multiple protein-protein interactions critical for tumor cell survival, tumor neovascularization, progression and metastasis. In this study, we investigated the anticancer activity of the FAK scaffold inhibitor C4, targeted to the FAK-VEGFR-3 complex, against melanomas. We compared C4 inhibitory effects in BRAF mutant vs BRAF wild type melanomas. C4 effectively caused melanoma tumor regression in vivo, when administered alone and sensitized tumors to chemotherapy. The most dramatic effect of C4 was related to reduction of vasculature of both BRAF wild type and V600E mutant xenograft tumors. The in vivo effects of C4 were assessed in xenograft models using non-invasive multimodality imaging in conjunction with histologic and molecular biology methods. C4 inhibited cell viability, adhesion and motility of melanoma and endothelial cells, specifically blocked phosphorylation of VEGFR-3 and FAK and disrupted their complexes. Specificity of in vivo effects for C4 were confirmed by a decrease in tumor FAK and VEGFR-3 phosphorylation, reduction of vasculogenesis and reduced blood flow. Our collective observations provide evidence that a small molecule inhibitor targeted to the FAK protein-protein interaction site successfully inhibits melanoma growth through dual targeting of tumor and endothelial cells and is effective against both BRAF wild type and mutant melanomas.

Autocrine secretion of 15d-PGJ2 mediates simvastatin-induced apoptotic burst in human metastatic melanoma cells

BACKGROUND AND PURPOSE

Despite new therapeutic approaches, metastatic melanomas still have a poor prognosis. Statins reduce low-density lipoprotein cholesterol and exert anti-inflammatory and anti-proliferative actions. We have recently shown that simvastatin triggers an apoptotic burst in human metastatic melanoma cells by the synthesis of an autocrine factor.

EXPERIMENTAL APPROACH

The current in vitro study was performed in human metastatic melanoma cell lines (A375, 518a2) and primary human melanocytes and melanoma cells. The secretome of simvastatin-stressed cells was analysed with two-dimensional difference gel electrophoresis and MS. The signalling pathways involved were analysed at the protein and mRNA level using pharmacological approaches and siRNA technology.

KEY RESULTS

Simvastatin was shown to activate a stress cascade, leading to the synthesis of 15-deoxy-12,14-PGJ2 (15d-PGJ2 ), in a p38- and COX-2-dependent manner. Significant concentrations of 15d-PGJ2 were reached in the medium of melanoma cells, which were sufficient to activate caspase 8 and the mitochondrial pathway of apoptosis. Inhibition of lipocalin-type PGD synthase, a key enzyme for 15d-PGJ2 synthesis, abolished the apoptotic effect of simvastatin. Moreover, 15d-PGJ2 was shown to bind to the fatty acid-binding protein 5 (FABP5), which was up-regulated and predominantly detected in the secretome of simvastatin-stressed cells. Knockdown of FABP5 abolished simvastatin-induced activation of PPAR-γ and amplified the apoptotic response.

CONCLUSIONS AND IMPLICATIONS

We characterized simvastatin-induced activation of the 15d-PGJ2 /FABP5 signalling cascades, which triggered an apoptotic burst in melanoma cells but did not affect primary human melanocytes. These data support the rationale for the pharmacological targeting of 15d-PGJ2 in metastatic melanoma.

Sensitivity of Melanoma Cells to EGFR and FGFR Activation but Not Inhibition is Influenced by Oncogenic BRAF and NRAS Mutations

BRAF and NRAS are the two most frequent oncogenic driver mutations in melanoma and are pivotal components of both the EGF and FGF signaling network. Accordingly, we investigated the effect of BRAF and NRAS oncogenic mutation on the response to the stimulation and inhibition of epidermal and fibroblast growth factor receptors in melanoma cells. In the three BRAF mutant, two NRAS mutant and two double wild-type cell lines growth factor receptor expression had been verified by qRT-PCR. Cell proliferation and migration were determined by the analysis of 3-days-long time-lapse videomicroscopic recordings. Of note, a more profound response was found in motility as compared to proliferation and double wild-type cells displayed a higher sensitivity to EGF and FGF2 treatment when compared to mutant cells. Both baseline and induced activation of the growth factor signaling was assessed by immunoblot analysis of the phosphorylation of the downstream effectors Erk1/2. Low baseline and higher inducibility of the signaling pathway was characteristic in double wild-type cells. In contrast, oncogenic BRAF or NRAS mutation did not influence the response to EGF or FGF receptor inhibitors in vitro. Our findings demonstrate that the oncogenic mutations in melanoma have a profound impact on the motogenic effect of the activation of growth factor receptor signaling. Since emerging molecularly targeted therapies aim at the growth factor receptor signaling, the appropriate mutational analysis of individual melanoma cases is essential in both preclinical studies and in the clinical trials and practice.

Addition of bevacizumab enhances antitumor activity of erlotinib against non-small cell lung cancer xenografts depending on VEGF expression

PURPOSE

Erlotinib, an epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), and bevacizumab, an anti-vascular endothelial growth factor (VEGF) agent, are promising therapies for advanced non-small cell lung cancer (NSCLC). Our study was aimed to determine whether there were conditions under which the addition of bevacizumab would enhance the antitumor activity of erlotinib against NSCLC tumors in vitro and in vivo.

METHODS

MTS was for NSCLC cell (PC9, 11-18, H1975, H157, H460 and A549) growth assay in vitro. ELISA was for VEGF protein assay in cells and tumor tissues. Mouse xenograft models were established with H157, H460 and A549 with primary resistance to erlotinib and treated with erlotinib plus bevacizumab or each agent alone. Erlotinib concentrations in tumors were determined by high-performance liquid chromatography.

RESULTS

Bevacizumab alone did not inhibit NSCLC cell growth in vitro. In primarily erlotinib-resistant NSCLC cells, the levels of VEGF protein were highest in H157 cell followed in order by H460 and A549 cells. In vivo, bevacizumab alone significantly inhibited tumor growth only in xenograft models with high (H157) and/or moderate (H460) levels of VEGF protein. A combination of erlotinib and bevacizumab partially reversed resistance to erlotinib in H157 xenografts (high VEGF level) with increasing intratumoral erlotinib concentrations, but not in H460 (moderate) or A549 (low) xenografts.

CONCLUSIONS

These results support that combined with anti-VEGF therapy could enhance antitumor activity of anti-EGFR therapy and/or partially reverse resistance to EGFR TKI, by increasing EGFR TKI concentration in specific tumors that express high levels of VEGF protein.

Enhanced anti-angiogenic effect of E7820 in combination with erlotinib in epidermal growth factor receptor-tyrosine kinase inhibitor-resistant non-small-cell lung cancer xenograft models

Most non-small-cell lung cancers (NSCLCs) harboring activating mutations in the epidermal growth factor receptor (EGFR) are initially responsive to EGFR tyrosine kinase inhibitors (EGFR-TKIs); however, they invariably develop resistance to these drugs. E7820 is an angiogenesis inhibitor that decreases integrin-α2 expression and is currently undergoing clinical trials. We investigated whether E7820 in combination with erlotinib, an EGFR-TKI, could overcome EGFR-TKI-resistance in the NSCLC cell lines A549 (KRAS; G12S), H1975 (EGFR; L858R/T790M), and H1650 (PTEN; loss, EGFR; exon 19 deletion), which are resistant to erlotinib. Immunohistochemical analysis was carried out in xenografted tumors to investigate anti-angiogenesis activity and endothelial cell apoptosis levels by endothelial cell marker CD31 and TUNEL staining, respectively. Treatment with E7820 (50 mg/kg) with erlotinib (60 mg/kg) showed a synergistic antitumor effect in three xenograft models. Immunohistochemical analysis indicated that combined treatment with E7820 and erlotinib significantly decreased microvessel density and increased apoptosis of tumor-associated endothelial cells compared with use of only one of the agents. This combination increased apoptosis in HUVECs through activation of both intrinsic and extrinsic apoptosis pathways in vitro. The combination of E7820 with erlotinib is an alternative strategy to overcome erlotinib resistance in NSCLC by enhancement of the anti-angiogenic activity of E7820.

Towards combinatorial targeted therapy in melanoma: from pre-clinical evidence to clinical application (review)

Over the last few years, clinical trials with BRAF and mitogen-activated protein/extracellular signal-regulated kinase (MEK) inhibitors have shown significant clinical activity in melanoma, but only a fraction of patients respond to these therapies, and development of resistance is frequent. This has prompted a large set of preclinical studies looking at several new combinatorial approaches of pathway- or target-specific inhibitors. At least five main drug association strategies have been verified in vitro and in preclinical models. The most promising include: i) vertical targeting of either MEK or phosphoinositide-3 kinase (PI3K)/mammalian target of rapamycin (mTOR) pathways, or their combined blockade; ii) association of receptor tyrosine kinases (RTKs) inhibitors with other pro-apoptotic strategies; iii) engagement of death receptors in combination with MEK-, mTOR/PI3K-, histone deacetylase (HDAC)-inhibitors, or with anti-apoptotic molecules modulators; iv) strategies aimed at blocking anti-apoptotic proteins belonging to B-cell lymphoma (Bcl-2) or inhibitors of apoptosis (IAP) families associated with MEK/BRAF/p38 inhibition; v) co-inhibition of other molecules important for survival [proteasome, HDAC and Signal transducers and activators of transcription (Stat)3] and the major pathways activated in melanoma; vi) simultaneous targeting of multiple anti-apoptotic molecules. Here we review the anti-melanoma efficacy and mechanism of action of the above-mentioned combinatorial strategies, together with the potential clinical application of the most promising studies that may eventually lead to therapeutic benefit.

Expression and activity of EGFR in human cutaneous melanoma cell lines and influence of vemurafenib on the EGFR pathway

Data regarding the expression of epidermal growth factor receptor (EGFR) in melanoma and its role in the tumor biology are conflicting. In BRAF V600-mutant melanomas, the expression of EGFR has been associated with acquired resistance to BRAF inhibitors. In this study, we assessed EGFR expression and downstream signaling activity in a panel of melanoma cell lines and we investigated the effects of the BRAF inhibitor vemurafenib on expression of EGFR and its downstream effectors in a subgroup of BRAF-mutant melanoma cells. Three out of 10 melanoma cell lines expressed EGFR. Downstream signaling via ERK and AKT was responsive to either stimulation by EGF or inhibition by erlotinib. Constitutive activation of ERK occurred in all the cell lines investigated whereas constitutive activation of AKT only in three cell lines. Constitutive activation of ERK and AKT was independent from EGFR expression. Vemurafenib did not affect EGFR expression in general, but it increased EGFR phosphorylation in the cell line SkMel5. Induced EGFR phosphorylation was sensitive to treatment with erlotinib. Vemurafenib efficiently blocked ERK activation in all the BRAF-mutant cell lines tested, whereas its effects on AKT activation were dissimilar in the different cell lines. Our data suggest that EGFR is functional but usually inactive in EGFR high-expressing cell lines. Basal EGFR expression unlikely represents a biomarker for predicting the sensitivity to vemurafenib in melanoma, but EGFR activation might represent a mechanism of vemurafenib resistance in a subset of melanoma cells.

Heat-shock proteins-based immunotherapy for advanced melanoma in the era of target therapies and immunomodulating agents

INTRODUCTION

Heat-shock proteins (HSPs) are highly conserved, stress-induced proteins that function as chaperones, stabilizing proteins and delivering peptides. Tumor-derived HSP peptide complexes (HSPPCs) induced immunity against several malignancies in preclinical models, exhibiting activity across tumor types.

AREAS COVERED

HSPPC-based vaccination showed clinical activity in subsets of patients with different malignancies (e.g., gastric, colorectal, pancreatic, ovarian cancer, and glioblastoma). In Phase III clinical trials for advanced melanoma and renal cell carcinoma patients, HSPPC-based vaccine demonstrated an excellent safety profile, thus emerging as a flexible tumor- and patient-specific therapeutic approach.

EXPERT OPINION

Melanoma, renal clear cell carcinoma, and glioblastoma are among suitable targets for HSP-based treatment as demonstrated by immune responses and clinical activity observed in subsets of patients, mainly those with early stage of disease and limited tumor burden. In order to further improve clinical activity, combinations of HSPPC-based vaccines with mutation-driven therapies, antiangiogenic agents, or immunomodulating monoclonal antibodies should be tested in controlled clinical trials.

The scope of nanoparticle therapies for future metastatic melanoma treatment

Metastatic melanoma is a highly aggressive malignancy that has traditionally been very difficult to treat. However, after decades of basic research into the signal transduction pathways that promote cancer cell survival, chemoresistance, growth, and crosstalk with the immune system, targeted therapies have now been developed that offer improved survival for patients with metastatic melanoma. Some of the most promising therapies that have been developed include ipilimumab, an anti-cytotoxic T lymphocyte antigen 4 antibody that enhances T-cell activity in the tumour, and selective BRAF inhibitors, such as vemurafenib that blocks tumour cell proliferation in patients with activating BRAF mutations. Although these treatments offer substantial hope for patients, they are not without their drawbacks, which include adverse side-effects, drug resistance, and eventual relapse. Nanotherapeutics holds significant promise to circumvent these shortcomings and has the additional advantage of potentially functioning as a diagnostic device. We will discuss the scope of the use of such multimodal nanoparticles for melanoma treatment and ask whether such particles can offer patients with metastatic melanoma improved prognoses for the future.

Axitinib affects cell viability and migration of a primary foetal lung adenocarcinoma culture

Fetal lung adenocarcinoma (FLAC) is a rare variant of lung adenocarcinoma. Studies regarding FLAC have been based only on histopathological observations, thus representative in vitro models of FLAC cultures are unavailable. We have established and characterized a human primary FLAC cell culture, exploring its biology, chemosensitivity, and migration. FLAC cells and specimen showed significant upregulation of VEGF165 and HIF-1α mRNA levels. This observation was confirmed by in vitro chemosensitivity and migration assay, showing that only Axitinib was comparable to Cisplatin treatment. We provide a suitable in vitro model to further investigate the nature of this rare type of cancer.

Oncogenes in melanoma: an update

Melanoma is a highly aggressive tumour with poor prognosis in the metastatic stage. BRAF, NRAS, and KIT are three well-known oncogenes involved in melanoma pathogenesis. Targeting of mutated BRAF kinase has recently been shown to significantly improve overall survival of metastatic melanoma patients, underscoring the particular role of this oncogene in melanoma biology. However, recurrences regularly occur within several months, which supposedly involve further oncogenes. Moreover, oncogenic driver mutations have not been described for up to 30% of all melanomas. In order to obtain a more complete picture of the mutational landscape of melanoma, more recent studies used high-throughput DNA sequencing technologies. A number of new oncogene candidates such as MAPK1/2, ERBB4, GRIN2A, GRM3, RAC1, and PREX2 were identified. Their particular role in melanoma biology is currently under investigation. Evidence for the functional relevance of some of these new oncogene candidates has been provided in in vitro and in vivo experiments. However, these findings await further validation in clinical studies. This review provides an overview on well-known melanoma oncogenes and new oncogene candidates, based on recent high-throughput sequencing studies. The list of genes discussed herein is of course not complete but highlights some of the most significant of recent findings in this area. The new candidates may support more individualized treatment approaches for metastatic melanoma patients in the future.

A randomized phase III trial on maintenance treatment with bevacizumab alone or in combination with erlotinib after chemotherapy and bevacizumab in metastatic colorectal cancer: the Nordic ACT Trial

BACKGROUND

The main objective was to study the effect on progression-free survival (PFS) of adding erlotinib to bevacizumab as maintenance treatment following chemotherapy and bevacizumab as first-line treatment of metastatic colorectal cancer (mCRC).

PATIENTS AND METHODS

Patients with untreated mCRC received doublet chemotherapy + bevacizumab during 18 weeks and those without tumor progression were eligible for randomization to bevacizumab + erlotinib (arm A) or bevacizumab alone (arm B), until progression or unacceptable toxic effect.

RESULTS

Of the 249 patients enrolled, 80 started maintenance treatment in arm A and 79 in arm B. The rate of any grade 3/4 toxic effect was 53% in arm A and 13% in arm B. Median PFS was 5.7 months in arm A and 4.2 months in arm B (HR = 0.79; 95% confidence interval 0.55-1.12; P = 0.19). Overall survival (OS) from start of induction chemotherapy was 26.7 months in the randomized population, with no difference between the two arms.

CONCLUSIONS

The addition of erlotinib to bevacizumab as maintenance treatment after first-line chemotherapy in mCRC did not improve PFS significantly. On-going clinical and translational studies focus on identifying subgroups of patients that may benefit from erlotinib in the maintenance setting.

CLINICAL TRIALS NUMBER

NCT00598156.

A novel synergistic effect of iron depletion on antiangiogenic cancer therapy

Iron is an essential element for both normal and cancer cells in humans. Treatment to reduce iron levels has been shown to suppress tumor growth in vivo. However, iron depletion monotherapy by iron decreased treatment has not been thought to be superior to ordinary chemotherapy and is not part of the standard therapeutic strategy for the treatment of cancer. Iron depletion is also known to reduce serum hemoglobin and oxygen supply to the tissue, which indicates that iron depletion may induce angiogenesis. Therefore, we hypothesized that iron depletion with antiangiogenic therapy can have a novel therapeutic effect in the treatment of cancer. Human nonsmall cell carcinoma cell lines A549 and H1299 were used in our study. An iron-deficient diet and an iron chelator were used to simulate an iron-depleted condition. The antitumor effects of iron depletion and antiangiogenic therapy were determined on A549 xenograft mice. The iron-depleted condition produced by an iron-deficient diet suppressed tumor growth. Tumor tissue from the iron-deficient diet group showed that cancer cell proliferation was suppressed and hypoxia was induced. Microvessel density of this group was increased which suggested that the iron-depleted condition induced angiogenesis. Bevacizumab administration had a synergetic effect on inhibiting the tumor growth on Day 39. An iron-depleted condition inhibited cancer cell proliferation and reciprocally induced angiogenesis. Bevacizumab synergistically enhanced the iron-depleted antitumor effect. Treatment to deplete iron levels combined with anti-angiogenic therapy could induce a novel therapeutic effect in the treatment of cancer.

Erlotinib and bevacizumab in newly diagnosed performance status 2 or elderly patients with nonsquamous non-small-cell lung cancer, a phase II study of the Hoosier Oncology Group: LUN04-77

BACKGROUND

Poor PS is a negative prognostic factor for survival and a risk factor for treatment-related toxicity with standard platinum-doublet chemotherapy for advanced NSCLC. A phase II study combining erlotinib and bevacizumab for treatment of recurrent NSCLC showed encouraging efficacy and acceptable toxicity.

PATIENTS AND METHODS

This single-arm phase II study evaluated erlotinib and bevacizumab as first-line therapy for newly diagnosed nonsquamous advanced NSCLC patients with Eastern Cooperative Oncology Group PS ≥ 2 or age 70 or older. Only patients eligible for bevacizumab per label were enrolled. Patients received erlotinib 150 mg orally daily and bevacizumab 15 mg/kg intravenously on day 1 every 21 days for up to 6 cycles. The primary end point was the rate of nonprogressive disease at 4 months (alternative hypothesis > 60%).

RESULTS

Twenty-five patients were enrolled, with median age 77 years (range, 52-90 years), 44% female, 20% never- or remote-smokers. Ninety-two percent of patients enrolled had PS of 2 per investigator assessment. The rate of nonprogressive disease at 4 months was 28%. There were no complete responses, 1 patient achieved a partial response, and 11 patients (44%) experienced stable disease as best response. Rash, fatigue, and diarrhea were the most common toxicities.

CONCLUSION

The combination of erlotinib and bevacizumab had insufficient activity in the absence of known activating epidermal growth factor receptor gene mutations to warrant study in newly diagnosed elderly or poor PS patients with nonsquamous NSCLC.

Proteome analysis identified the PPARγ ligand 15d-PGJ2 as a novel drug inhibiting melanoma progression and interfering with tumor-stroma interaction

Peroxisome proliferator-activated receptors (PPARs) have been originally thought to be restricted to lipid metabolism or glucose homeostasis. Recently, evidence is growing that PPARγ ligands have inhibitory effects on tumor growth. To shed light on the potential therapeutic effects on melanoma we tested a panel of PPAR agonists on their ability to block tumor proliferation in vitro. Whereas ciglitazone, troglitazone and WY14643 showed moderate effects on proliferation, 15d-PGJ2 displayed profound anti-tumor activity on four different melanoma cell lines tested. Additionally, 15d-PGJ2 inhibited proliferation of tumor-associated fibroblasts and tube formation of endothelial cells. 15d-PGJ2 induced the tumor suppressor gene p21, a G₂/M arrest and inhibited tumor cell migration. Shot gun proteome analysis in addition to 2D-gel electrophoresis and immunoprecipitation of A375 melanoma cells suggested that 15d-PGJ2 might exert its effects via modification and/or downregulation of Hsp-90 (heat shock protein 90) and several chaperones. Applying the recently established CPL/MUW database with a panel of defined classification signatures, we demonstrated a regulation of proteins involved in metastasis, transport or protein synthesis including paxillin, angio-associated migratory cell protein or matrix metalloproteinase-2 as confirmed by zymography. Our data revealed for the first time a profound effect of the single compound 15d-PGJ2 on melanoma cells in addition to the tumor-associated microenvironment suggesting synergistic therapeutic efficiency.

Melanoma: from mutations to medicine

Melanoma is often considered one of the most aggressive and treatment-resistant human cancers. It is a disease that, due to the presence of melanin pigment, was accurately diagnosed earlier than most other malignancies and that has been subjected to countless therapeutic strategies. Aside from early surgical resection, no therapeutic modality has been found to afford a high likelihood of curative outcome. However, discoveries reported in recent years have revealed a near avalanche of breakthroughs in the melanoma field-breakthroughs that span fundamental understanding of the molecular basis of the disease all the way to new therapeutic strategies that produce unquestionable clinical benefit. These discoveries have been born from the successful fruits of numerous researchers working in many-sometimes-related, although also distinct-biomedical disciplines. Discoveries of frequent mutations involving BRAF(V600E), developmental and oncogenic roles for the microphthalmia-associated transcription factor (MITF) pathway, clinical efficacy of BRAF-targeted small molecules, and emerging mechanisms underlying resistance to targeted therapeutics represent just a sample of the findings that have created a striking inflection in the quest for clinically meaningful progress in the melanoma field.

Novel biomarkers and therapeutic targets for optimizing the therapeutic management of melanomas

Cutaneous malignant melanoma is the most aggressive form of skin cancer with an extremely poor survival rate for the patients diagnosed with locally invasive and metastatic disease states. Intensive research has led in last few years to an improvement of the early detection and curative treatment of primary cutaneous melanomas that are confined to the skin by tumor surgical resection. However, locally advanced and disseminated melanomas are generally resistant to conventional treatments, including ionizing radiation, systemic chemotherapy, immunotherapy and/or adjuvant stem cell-based therapies, and result in the death of patients. The rapid progression of primary melanomas to locally invasive and/or metastatic disease states remains a major obstacle for an early effective diagnosis and a curative therapeutic intervention for melanoma patients. Importantly, recent advances in the melanoma research have led to the identification of different gene products that are often implicated in the malignant transformation of melanocytic cells into melanoma cells, including melanoma stem/progenitor cells, during melanoma initiation and progression to locally advanced and metastatic disease states. The frequent deregulated genes products encompass the oncogenic B-RafV600E and N-RasQ61R mutants, different receptor tyrosine kinases and developmental pathways such as epidermal growth factor receptor (EGFR), stem cell-like factor (SCF) receptor KIT, hedgehog, Wnt/β-catenin, Notch, stromal cell-derived factor-1 (SDF-1)/CXC chemokine receptor-4 (CXCR4) and vascular endothelial growth factor (VEGF)/VEGFR receptor. These growth factors can cooperate to activate distinct tumorigenic downstream signaling elements and epithelial-mesenchymal transition (EMT)-associated molecules, including phosphatidylinositol 3’-kinase (PI3K)/Akt/ molecular target of rapamycin (mTOR), nuclear factor-kappaB (NF-κB), macrophage inhibitory cytokine-1 (MIC-1), vimentin, snail and twist. Of therapeutic relevance, these deregulated signal transduction components constitute new potential biomarkers and therapeutic targets of great clinical interest for improving the efficacy of current diagnostic and prognostic methods and management of patients diagnosed with locally advanced, metastatic and/or relapsed melanomas.

The immunological era in melanoma treatment: new challenges for heat shock protein-based vaccine in the advanced disease

INTRODUCTION

Tumor-derived heat shock protein (HSP)-peptide complexes (HSPPCs) induced immunity against malignancies in preclinical trials, working across tumor types and bypassing the need to identify single immunogenic peptides. These results paved the way for the use of human gp96 obtained from autologous tumor samples as an anti-cancer vaccine.

AREAS COVERED

Autologous tumor-derived HSP gp96 peptide complex (HSPPC-96) vaccine is emerging as a tumor- and patient-specific cancer vaccine, with confirmed activity in several malignancies. It has been tested in Phase III clinical trials in advanced melanoma and kidney cancer with evidence for efficacy in patients with earlier stage disease. HSPPC-96-based vaccine demonstrated an excellent safety profile, thus emerging as a novel therapeutic approach with a suggestive role in cancer therapy. This review summarizes work on the use of HSPPC-96 as an autologous anti-tumor vaccine in advanced melanoma. Data were retrieved by PubMed and Medline research and using the authors' personal experience.

EXPERT OPINION

Further investigations are needed to understand the biological basis of immune functions in order to improve the clinical outcome of HSP-based cancer therapy. In the near future, the combination of HSP-based vaccines with other biological compounds might represent a successful strategy in the therapy of advanced melanoma.

New therapeutic options in the medical management of advanced melanoma

During the past 3 decades, the incidence, morbidity, and mortality of malignant melanoma have increased dramatically. Advanced melanoma has remained a disease that is for the most part incurable and has challenged all therapeutic efforts to make a dent in its natural history. Recent advances in the understanding of the molecular alterations in melanoma and in the immunologic mechanisms playing a role in this malignancy have brought hope that significant progress can be achieved, as evidenced by early encouraging clinical data. This review will summarize these recent developments and their impact on current clinical practice.

Efficacy of bevacizumab plus erlotinib versus erlotinib alone in advanced non-small-cell lung cancer after failure of standard first-line chemotherapy (BeTa): a double-blind, placebo-controlled, phase 3 trial

BACKGROUND

Bevacizumab and erlotinib target different tumour growth pathways with little overlap in their toxic-effect profiles. On the basis of promising results from a phase 1/2 trial assessing safety and activity of erlotinib plus bevacizumab for recurrent or refractory non-small-cell lung cancer (NSCLC), we aimed to assess efficacy and safety of this combination in a phase 3 trial.

METHODS

In our double-blind, placebo-controlled, randomised phase 3 trial (BeTa), we enrolled patients with recurrent or refractory NSCLC who presented to 177 study sites in 12 countries after failure of first-line treatment. Patients were randomly allocated in a one-to-one ratio to receive erlotinib plus bevacizumab (bevacizumab group) or erlotinib plus placebo (control group) according to a computer-generated randomisation sequence by use of an interactive voice response system. The primary endpoint was overall survival in all enrolled patients. Patients, study staff, and investigators were masked to treatment assignment. We assessed safety by calculation of incidence of adverse events and tissue was collected for biomarker analyses. This trial is registered with ClinicalTrials.gov, number NCT00130728.

FINDINGS

Overall survival did not differ between 317 controls and 319 patients in the bevacizumab group (hazard ratio [HR] 0·97, 95% CI 0·80-1·18, p=0·7583). Median overall survival was 9·3 months (IQR 4·1-21·6) for patients in the bevacizumab group compared with 9·2 months (3·8-20·2) for controls. Progression-free survival seemed to be longer in the bevacizumab group (3·4 months [1·4-8·4]) than in the control group (1·7 months [1·3-4·1]; HR 0·62, 95% CI 0·52-0·75) and objective response rate suggested some clinical activity of bevacizumab and erlotinib. However, these secondary endpoint differences could not be defined as significant because the study prespecified that the primary endpoint had to be significant before testing of secondary endpoints could be done, to control type I error rate. In the bevacizumab group, 130 (42%) of 313 patients with safety data had a serious adverse event, compared with 114 (36%) controls. There were 20 (6%) grade 5 adverse events, including two arterial thromboembolic events, in the bevacizumab group, and 14 (4%) in the control group.

INTERPRETATION

Addition of bevacizumab to erlotinib does not improve survival in patients with recurrent or refractory NSCLC.

FUNDING

Genentech.

Receptor tyrosine kinases and their activation in melanoma

Receptor tyrosine kinases (RTKs) and their downstream signalling pathways have long been hypothesized to play key roles in melanoma development. A decade ago, evidence was derived largely from animal models, RTK expression studies and detection of activated RAS isoforms in a small fraction of melanomas. Predictions that overexpression of specific RTKs implied increased kinase activity and that some RTKs would show activating mutations in melanoma were largely untested. However, technological advances including rapid gene sequencing, siRNA methods and phospho-RTK arrays now give a more complete picture. Mutated forms of RTK genes including KIT, ERBB4, the EPH and FGFR families and others are known in melanoma. Additional over- or underexpressed RTKs and also protein tyrosine phosphatases (PTPs) have been reported, and activities measured. Complex interactions between RTKs and PTPs are implicated in the abnormal signalling driving aberrant growth and survival in malignant melanocytes, and indeed in normal melanocytic signalling including the response to ultraviolet radiation. Kinases are considered druggable targets, so characterization of global RTK activity in melanoma should assist the rational development of tyrosine kinase inhibitors for clinical use.