Tyrosine kinase inhibitors as a first-line treatment in patients with newly diagnosed chronic myeloid leukemia in chronic phase: A mixed-treatment comparison.

Tyrosine kinase inhibitors (TKI) are the initial treatment for majority of newly diagnosed patients with chronic myelogenous leukemia (CML) in chronic phase (CP) and are associated with marked improvement in hematological, cytogenetic, molecular response and survival rates compared with other therapies. In this review, we summarize the evidence of TKI efficacy for patients with newly diagnosed CP-CML. Six trials at low risk of bias evaluating TKIs as an initial treatment in adults with newly diagnosed CP-CML and enrolling 2,456 patients were included. Follow-up times ranged from a median of 3 months to 5 years. Direct comparison showed statistically higher rates of major molecular response (MMR ≤ 0.1%(IS)) achievement with second-generation TKIs at 12 months which was sustained throughout treatment period. Bayesian mixed-treatment comparison (MTC) analysis demonstrated superiority of both nilotinib and dasatinib over imatinib in terms of efficacy. Nilotinib was associated with higher deeper molecular responses (MR(4.5) ≤ 0.0032%(IS)) at 60 months than dasatinib but no difference in MMR. The differences between nilotinib and dasatinib are likely clinically trivial. Among TKIs, nilotinib was found to have the best survival profile. Both nilotinib and dasatinib are associated with significantly better MMR compared to imatinib that is sustained over 60 months. This analysis shows that new-generation TKIs are not only showing faster response but also maintaining a more potent one through longer follow-up period. It is important to note out that MTC is not a substitute for well-conducted RCTs investigating direct comparisons.

The Effect of a Neutropenic Diet on Infection and Mortality Rates in Cancer Patients: A Meta-Analysis.

Neutropenic diets (ND) are often prescribed to cancer patients aiming to reduce infection risk. The goal of this meta-analysis was to determine if ND indeed reduced the risk of infection and death in cancer patients compared to regular diets (RD). We identified studies in cancer patients that compared the effect of ND vs. RD on the risk of infections and mortality of any cause. The overall effect was calculated by use of a random effects model. Four studies were identified encompassing 918 patients. There was no difference in major infection or mortality rates between ND and RD groups. When analyzing for the overall composite outcome of any infection or fever, the hazard ratio was significantly higher in the ND arm (relative risk = 1.18, confidence interval: 1.05 to 1.34, P= 0.007). When the analysis was restricted to only the randomized trials, both groups had a comparable composite outcome. This meta-analysis shows no superiority with respect to mortality or infection of using a neutropenic diet in cancer patients. Larger studies are needed that study a broader range of nutritional issues, including the microbiome, in this patient population. Until then, it may be time to relax the restrictions of ND.

Detection of EGFRvIII mutant DNA in the peripheral blood of brain tumor patients.

Glioblastoma multiforme (GBM) is the most aggressive brain tumor in adults and remains incurable despite multimodal intensive treatment regimens including surgical resection, radiation and chemotherapy. EGFRvIII is a truncated extracellular mutant of the EGF receptor (EGFR) found in about a third of GBMs. It confers enhanced tumorigenic behavior and is associated with chemo- and radio-resistance. GBM patients testing positive for EGFRvIII have a bleaker prognosis than those who do not. Targeting EGFRvIII positive tumors via vaccines or antibody-drug-conjugates represents a new challenging therapeutic avenue with potential great clinical benefits. In this study, we developed a strategy to detect EGFRvIII deletion in the circulating tumor DNA. The overall goal is to identify a simple and robust biomarker in the peripheral blood of patients diagnosed with GBM in order to follow their disease status while on treatment. Thirteen patients were included in this study, three of which were found to carry the EGFRvIII deletion. The circulating DNA status for EGFRvIII correlates with the analysis performed on the respective tumor samples, and its level seems to correlate with the extent of the tumor resection. This semi-quantitative blood biomarker may represent a strategy to (1) screen patients for an anti-EGFRvIII therapy and (2) monitor the patients' response to treatment.

ROS1 amplification mediates resistance to gefitinib in glioblastoma cells.

Glioblastoma (GBM) is the most aggressive brain tumor in adults and remains incurable despite multimodal intensive treatment regimens. The majority of GBM tumors show a mutated or overexpressed EGFR, however, tumors treated with tyrosine kinase inhibitors (TKIs) will inevitably recur highlighting the need to identify signalling pathways involved in GBM resistance to these drugs. To this end, we treated GBM cells that overexpress EGFR with increasing concentrations of gefitinib and isolated resistant clones. These resistant clones were subject to RNAseq and the expression of several genes was found to be upregulated. These genes are mainly tyrosine kinase receptors and include ROS1, DDR1 and PDGFRA and are known to control several downstream targets of EGFR. The upregulation of ROS1 and DDR1 was confirmed at the protein level by western blot. Treatment with a potent and highly specific pyrazole ROS1 inhibitor in ROS1 overexpressing clones led to a sensitization of these cells to low concentrations of gefitinib. Combined treatment with gefitinib and ROS1 inhibitor induces massive cell death by apoptosis following a prolonged S phase cell cycle arrest. Our current study led to the discovery of alternative pathways used by GBM cells to evade cell death following treatment with gefitinib and identifies new therapeutic targets to prevent GBM cell resistance to the drug.

Phase II Clinical Trial of Gefitinib for the Treatment of Chemonaïve Patients with Advanced Non-small Cell Lung Cancer with Poor Performance Status.

BACKGROUND: Patients with advanced non-small cell lung cancer (NSCLC) have no curative treatment options; therefore, improving their quality of life (QOL) is an important goal. Gefitinib, an epidermal growth factor receptor (EGFR) inhibitor, is a safe oral agent that may be of benefit to a specific population of NSCLC. PATIENTS AND METHODS: A Phase II clinical trial included chemonaïve patients with advanced NSCLC and poor performance status (PS). Response rate, progression-free survival, overall survival, QOL using the Functional Assessment of Cancer Therapy - Lung (FACT-L) questionnaire, and Trial Outcome Index (TOI) were evaluated. RESULTS: Twelve out of 19 enrolled patients were evaluable. The median age for the evaluable patients was 68.8 years (59.7-74.6). Out of all the patients, 7 (58.3%) had adenocarcinoma and 5 (41.7%) had squamous cell carcinoma. The median duration of treatment was 62.5 days (26.5-115.0) in the evaluable patients. Grade 3/4 toxicities included fatigue, rash, diarrhea, and nausea. One patient had partial response, eight patients had stable disease (SD), and three patients progressed. The median overall survival for the evaluable population was 4.9 months (2.3-16). The median progression-free survival was 3.7 months (1.9-6.6). TOI was marginally associated with the overall survival, with a hazard ratio of 0.92 (95% confidence interval: 0.84, 1.0) (P = 0.061). FACT-L score and the TOI were highly correlated (r = 0.96, P < 0.0001). TOI scores were higher in African Americans compared to Caucasians and increased with age. CONCLUSION: Our results suggest that gefitinib use in patients with NSCLC and poor PS may improve the QOL of older patients and African American patients.

The use of pharmacogenomics for selection of therapy in non-small-cell lung cancer.

INTRODUCTION: Performance status (PS) is the only known clinical predictor of outcome in patients with advanced non-small-cell lung cancer (NSCLC), although pharmacogenomic markers may also correlate with outcome. The aim of our study was to correlate clinical and pharmacogenomic measures with overall survival. METHODS: This was an IRB approved, retrospective study in which the medical records of 50 patients with advanced NSCLC from 1998-2008 were reviewed, and gender, race, PS, and chemotherapy regimens were documented. Stromal expression of pharmacogenomic markers (VEGFR, ERCC1, 14-3-3σ, pAKT, and PTEN) was measured. Clinical factors and pharmacogenomics markers were compared to overall survival using a Cox proportional hazards model. RESULTS: Forty patients received platinum-based therapy. Median age was 65 years. Improved PS, female gender, and gemcitabine therapy were significantly associated with longer overall survival (P = 0.004, P = 0.04, and P = 0.003, respectively). Age was not associated with survival. Caucasians had better overall survival in comparison to African Americans with median survival of 14.8 months versus 10.4 months (P = 0.1). Patients treated with platinum-based therapy had better survival of 15 months versus 8 months for non-platinum based therapy (P = 0.01). There was no significant association between any of the pharmacogenomics markers and overall survival other than in patients treated with platinum, in whom ERCC1 negativity was strongly associated with longer survival (P = 0.007). CONCLUSION: ERCC1 negativity with platinum therapy, gemcitabine therapy, good PS, and female gender all correlated with improved overall survival in patients with advanced NSCLC.

Comprehensive review of JAK inhibitors in myeloproliferative neoplasms.

Myeloproliferative neoplasms (MPNs) are clonal hematopoietic stem-cell disorders, characterized phenotypically by the abnormal accumulation of mature-appearing myeloid cells. Polycythemia vera, essential thrombocythemia, primary myelofibrosis (also known as 'BCR-ABL1-negative' MPNs), and chronic myeloid leukemia (CML) are the primary types of MPNs. After the discovery of the BCR-ABL1 fusion protein in CML, several oncogenic tyrosine kinases have been identified in 'BCR-ABL1-negative' MPNs, most importantly, JAK2V617F mutation. The similarity in the clinical characteristics of the BCR-ABL1-negative MPN patients along with the prevalence of the Janus kinase mutation in this patient population provided a strong rationale for the development of a new class of pharmacologic inhibitors that target this pathway. The first of its class, ruxolitinib, has now been approved by the food and drug administration (FDA) for the management of patients with intermediate- to high-risk myelofibrosis. Ruxolitinib provides significant and sustained improvements in spleen related and constitutional symptoms secondary to the disease. Although noncurative, ruxolitinib represents a milestone in the treatment of myelofibrosis patients. Other types of JAK2 inhibitors are being tested in various clinical trials at this point and may provide better efficacy data and safety profile than its predecessor. In this article, we comprehensively reviewed and summarized the available preclinical and clinical trials pertaining to JAK inhibitors.