Larotrectinib in adult patients with solid tumours: a multi-centre, open-label, phase I dose-escalation study.

BACKGROUND: NTRK1, NTRK2 and NTRK3 gene fusions (NTRK gene fusions) occur in a range of adult cancers. Larotrectinib is a potent and highly selective ATP-competitive inhibitor of TRK kinases and has demonstrated activity in patients with tumours harbouring NTRK gene fusions. PATIENTS AND METHODS: This multi-centre, phase I dose escalation study enrolled adults with metastatic solid tumours, regardless of NTRK gene fusion status. Key inclusion criteria included evaluable and/or measurable disease, Eastern Cooperative Oncology Group performance status 0-2, and adequate organ function. Larotrectinib was administered orally once or twice daily, on a continuous 28-day schedule, in increasing dose levels according to a standard 3 + 3 dose escalation scheme. The primary end point was the safety of larotrectinib, including dose-limiting toxicity. RESULTS: Seventy patients (8 with tumours with NTRK gene fusions; 62 with tumours without a documented NTRK gene fusion) were enrolled to 6 dose cohorts. There were four dose-limiting toxicities; none led to study drug discontinuation. The maximum tolerated dose was not reached. Larotrectinib-related adverse events were predominantly grade 1; none were grade 4 or 5. The most common grade 3 larotrectinib-related adverse event was anaemia [4 (6%) of 70 patients]. A dose of 100 mg twice daily was recommended for phase II studies based on tolerability and antitumour activity. In patients with evaluable TRK fusion cancer, the objective response rate by independent review was 100% (eight of the eight patients). Eight (12%) of the 67 assessable patients overall had an objective response by investigator assessment. Median duration of response was not reached. Larotrectinib had limited activity in tumours with NTRK mutations or amplifications. Pharmacokinetic analysis showed exposure was generally proportional to administered dose. CONCLUSIONS: Larotrectinib was well tolerated, demonstrated activity in all patients with tumours harbouring NTRK gene fusions, and represents a new treatment option for such patients. CLINCALTRIALS.GOV NUMBER: NCT02122913.

Overall survival analysis of EXAM, a phase III trial of cabozantinib in patients with radiographically progressive medullary thyroid carcinoma.

BACKGROUND: Primary analysis of the double-blind, phase III Efficacy of XL184 (Cabozantinib) in Advanced Medullary Thyroid Cancer (EXAM) trial demonstrated significant improvement in progression-free survival with cabozantinib versus placebo in patients with progressive medullary thyroid cancer (MTC). Final analysis of overall survival (OS), a key secondary endpoint, was carried out after long-term follow-up. PATIENTS AND METHODS: EXAM compared cabozantinib with placebo in 330 patients with documented radiographic progression of metastatic MTC. Patients were randomized (2:1) to cabozantinib (140 mg/day) or placebo. Final OS and updated safety data are reported. RESULTS: Minimum follow-up was 42 months. Kaplan-Meier analysis showed a 5.5-month increase in median OS with cabozantinib versus placebo (26.6 versus 21.1 months) although the difference did not reach statistical significance [stratified hazard ratio (HR), 0.85; 95% confidence interval (CI), 0.64-1.12; P = 0.24]. In an exploratory assessment of OS, progression-free survival, and objective response rate, cabozantinib appeared to have a larger treatment effect in patients with RET M918T mutation-positive tumors compared with patients not harboring this mutation. For patients with RET M918T-positive disease, median OS was 44.3 months for cabozantinib versus 18.9 months for placebo [HR, 0.60; 95% CI, 0.38-0.94; P = 0.03 (not adjusted for multiple subgroup analyses)], with corresponding values of 20.2 versus 21.5 months (HR, 1.12; 95% CI, 0.70-1.82; P = 0.63) in the RET M918T-negative subgroup. Median treatment duration was 10.8 months with cabozantinib and 3.4 months with placebo. The safety profile for cabozantinib remained consistent with that of the primary analysis. CONCLUSION: The secondary end point was not met in this final OS analysis from the trial of cabozantinib in patients with metastatic, radiographically progressive MTC. A statistically nonsignificant increase in OS was observed for cabozantinib compared with placebo. Exploratory analyses suggest that patients with RET M918T-positive tumors may experience a greater treatment benefit with cabozantinib. TRIAL REGISTRATION NUMBER: NCT00704730.

Efatutazone, an oral PPAR-γ agonist, in combination with paclitaxel in anaplastic thyroid cancer: results of a multicenter phase 1 trial.

PURPOSE: A phase 1 study was initiated to determine the safety, potential effectiveness, and maximal tolerated dose and recommended phase 2 dose of efatutazone and paclitaxel in anaplastic thyroid cancer. EXPERIMENTAL DESIGN: Patients received efatutazone (0.15, 0.3, or 0.5 mg) orally twice daily and then paclitaxel every 3 weeks. Patient tolerance and outcomes were assessed, as were serum efatutazone pharmacokinetics. RESULTS: Ten of 15 patients were women. Median age was 59 years. Seven patients received 0.15 mg of efatutazone, 6 patients received 0.3 mg, and 2 patients received 0.5 mg. One patient receiving 0.3 mg of efatutazone had a partial response from day 69 to day 175; 7 patients attained stable disease. Median times to progression were 48 and 68 days in patients receiving 0.15 mg of efatutazone and 0.3 mg of efatutazone, respectively; corresponding median survival was 98 vs 138 days. The median peak efatutazone blood level was 8.6 ng/mL for 0.15-mg dosing vs 22.0 ng/mL for 0.3-mg twice daily dosing. Ten patients had grade 3 or greater adverse events (Common Terminology Criteria for Adverse Events), with 2 of these (anemia and edema) related to efatutazone. Thirteen events of edema were reported in 8 patients, with 2 of grade 3 or greater. Eight patients had ≥1 serious adverse event, with 1 of these (anemia) attributed to efatutazone and 1 (anaphylactic reaction) related to paclitaxel. The maximal tolerated dose was not achieved. Angiopoietin-like 4 was induced by efatutazone in tissue biopsy samples of 2 patients. CONCLUSIONS: Efatutazone and paclitaxel in combination were safe and tolerated and had biologic activity.

Effect of the phosphodiesterase 4 inhibitor roflumilast on glucose metabolism in patients with treatment-naive, newly diagnosed type 2 diabetes mellitus.

CONTEXT: The phosphodiesterase 4 inhibitor roflumilast is a first-in-class antiinflammatory treatment for severe chronic obstructive pulmonary disease (COPD) associated with chronic bronchitis and a history of frequent exacerbations. In previous clinical studies, a transient and reversible weight decrease was reported with roflumilast, suggesting the systemic actions of this drug may impact metabolism. OBJECTIVE: Our objective was to investigate the effects of roflumilast on glucose homeostasis and body weight. DESIGN AND SETTING: We conducted a 12-wk, randomized, double-blind, placebo-controlled multicenter study with outpatients. PATIENTS: Patients (n = 205) with newly diagnosed type 2 diabetes mellitus (DM2) but without COPD were included in the study. INTERVENTIONS: Roflumilast 500 µg or placebo was administered once daily. PRIMARY OUTCOME: We evaluated mean change in blood glycated hemoglobin levels. SECONDARY OUTCOMES: We also evaluated mean change from baseline in the postmeal area under the curve (AUC) for a range of metabolic parameters. RESULTS: Roflumilast was associated with a significantly greater reduction in glycated hemoglobin levels than placebo (least square mean = -0.45%; P < 0.0001) in patients with DM2. In the roflumilast group, postmeal AUC decreased significantly from baseline to last visit for free fatty acids, glycerol, glucose, and glucagon, whereas they slightly increased for C-peptide and insulin. In contrast to roflumilast, the glucagon AUC increased with placebo, and the insulin AUC decreased. Between-treatment analysis revealed statistically significant differences in favor of roflumilast for glucose (P = 0.0082), glycerol (P = 0.0104), and C-peptide levels (P = 0.0033). Patients in both treatment groups lost weight, although the between-treatment difference of the changes from baseline to last visit [-0.7 (0.4) kg] was not statistically significant (P = 0.0584). CONCLUSION: Roflumilast lowered glucose levels in patients with newly diagnosed DM2 without COPD, suggesting positive effects on glucose homoeostasis.

Roflumilast with long-acting ß2-agonists for COPD: influence of exacerbation history.

The oral, selective phosphodiesterase type-4 inhibitor roflumilast reduces exacerbations and improves lung function in patients with severe-to-very severe chronic obstructive pulmonary disease (COPD). We investigated the efficacy and safety of roflumilast used concomitantly with long-acting ß(2)-agonists (LABAs) to reduce exacerbations, and the influence of exacerbation history. Pooled data were analysed from two 12-month, placebo-controlled roflumilast (500 µg once daily) studies involving 3,091 patients with severe-to-very severe COPD. Approximately half of patients used concomitant LABAs; 39% used concomitant short-acting muscarinic antagonists (SAMAs); 27% were frequent exacerbators (two or more exacerbations per year). Roflumilast reduced the rate of moderate or severe exacerbations, with LABA (rate ratio (RR) 0.79, 95% CI 0.69-0.91; p=0.001) or without LABA (RR 0.85, 95% CI 0.74-0.99; p=0.039) and prolonged time both to first (p=0.035 with LABA, p=0.300 without LABA) and second (p=0.018 with LABA, p=0.049 without LABA) exacerbations. Frequent exacerbators experienced a reduction in moderate or severe exacerbations (RR 0.78, 95% CI 0.66-0.91; p=0.002). Similarly, roflumilast remained effective with concomitant SAMA. No differences arose in adverse events between these subgroups. Roflumilast may be used to reduce exacerbations and improve dyspnoea and lung function, without increasing adverse events in COPD patients receiving concomitant LABAs.

Targeted inhibition of CD133+ cells in oral cancer cell lines.

UNLABELLED: Resistance to treatment and the appearance of secondary tumors in head and neck squamous cell carcinomas (HNSCC) have been attributed to the presence of cells with stem-cell-like properties in the basal layer of the epithelium at the site of the lesion. In this study, we tested the hypothesis that these putative cancer stem cells (CSC) in HNSCC could be specifically targeted and inhibited. We found that 9 of 10 head and neck tumor biopsies contained a subpopulation of cells that expressed CD133, an unusual surface-exposed membrane-spanning glycoprotein associated with CSC. A genetically modified cytolethal distending toxin (Cdt), from the periodontal pathogen Aggregatibacter actinomycetemcomitans, was conjugated to an anti-human CD133 monoclonal antibody (MAb). The Cdt-MAb complex preferentially inhibited the proliferation of CD133(+) cells in cultures of established cell lines derived from HNSCC. Inhibition of the CD133(+) cells was rate- and dose-dependent. Saturation kinetics indicated that the response to the Cdt-MAb complex was specific. Healthy primary gingival epithelial cells that are native targets of the wild-type Cdt were not affected. Analysis of these data provides a foundation for the future development of new therapies to target CSC in the early treatment of HNSCC. ABBREVIATIONS: Cdt, cytolethal distending toxin; CSC, cancer stem cells; HNSCC, head and neck squamous cell carcinoma; MAb, monoclonal antibody.

The RET/PTC3 oncogene activates classical NF-κB by stabilizing NIK.

The oncogenic fusion protein RET/PTC3 (RP3) that is expressed in papillary thyroid carcinoma (PTC) and thyroid epithelia in Hashimoto's thyroiditis activates nuclear factor-kappa B (NF-κB) and induces pro-inflammatory gene expression; however, the mechanism of this activation is unknown. To address this, we expressed RP3 in murine embryonic fibroblasts (MEFs) lacking key classical and noncanonical NF-κB signaling components. In wild-type MEFs, RP3 upregulated CCL2, CXCL1, granulocyte-macrophage colony-stimulating factor and tumor necrosis factor expression and activated classical but not noncanonical NF-κB. RP3-activated NF-κB in IκB kinase (IKK)ß(-/-) MEFs but not IKKα- or NF-κB essential modulator (NEMO)-deficient cells and activation was inhibited by a peptide that blocks NEMO binding to the IKKs. RP3 increased the levels of NF-κB-inducing kinase (NIK) and did not activate NF-κB in NIK-deficient MEFs. Notably, NIK stabilization was not accompanied by TRAF3 degradation demonstrating that RP3 disrupts normal basal NIK regulation. Dominant-negative NIK blocked RP3-induced NF-κB activation and an RP3 signaling mutant (RP3(Y588F)) did not stabilize NIK. Finally, examination of PTC specimens revealed strong positive staining for NIK. We therefore conclude that RP3 activates classical NF-κB via NIK, NEMO and IKKα. Importantly, our findings reveal a novel mechanism for oncogene-induced NF-κB activation via stabilization of NIK.

A comparative study of EGFR mutation screening methods in non-small cell carcinoma of lung.

Epidermal growth factor receptor (EGFR) is a transmembrane receptor tyrosine kinase of the ERBB2 family that has important roles in the proliferation and metastasis of tumor cells. It is frequently overexpressed in common solid tumors and has become a favored target for orally administered small-molecule tyrosine kinase inhibitors (TKI) and monoclonal antibody-based therapy. Gain-of-function somatic mutations of the EGFR tyrosine kinase domain have been associated with the response of some patients with non-small-cell lung carcinoma to TKIs. We evaluated three methods of EGFR mutation analysis to identify an optimal assay for clinical testing based on comparison of diagnostic sensitivity, technical difficulty, and cost (Tab. 1, Fig. 1, Ref. 12).

Characterization of two novel BRCA1 germ-line mutations involving splice donor sites.

Deleterious BRCA1 mutations have significant clinical implications for the patients that carry them. Point mutations in critical functional domains and frameshift mutations that lead to early termination of protein translation are associated with a 60-80% risk of breast cancer and a 20-40% risk of ovarian cancer. In contrast, the significance of mutations located in intronic regions of BRCA1, even in the setting of a family history of breast and ovarian cancer, is not always clear. Some of these mutations occur in splice donor/acceptor consensus sites. These mutations can affect heteronuclear RNA (hnRNA) processing, leading to the loss of functional BRCA1 protein and thus may be disease-associated. However, it is important to verify the effect of these mutations, because splicing alterations cannot be predicted from genomic sequence alone. We report here the characterization of two novel BRCA1 mutations identified in families seen in our cancer risk evaluation clinic that alter splice donor sites of BRCA1. We show that both mutations alter transcript splicing and result in truncated BRCA1. IVS17 + 1G --> T leads to inclusion of part of intron 17 after the coding sequence of exon 17, resulting in early termination of BRCA1 protein following codon 1692. 252del5insT abolishes the splice donor site in exon 3, leading to the skipping of exon 5 and BRCA1 protein truncation following codon 45. Thus, both mutations result in loss of BRCA1 function, and carriers of these mutations should be counseled in the same manner as carriers of other truncating BRCA1 mutations.

Absence of BRAF mutations in UV-protected mucosal melanomas.

BACKGROUND: Mutations in BRAF have recently been identified in a significant percentage of primary and metastatic cutaneous malignant melanomas. As ultraviolet (UV) exposure may play a role in the development of cutaneous melanoma lesions with BRAF mutations, BRAF mutation frequency in melanomas arising in sites protected from sun exposure may be lower than those from sun-exposed areas. Thus, we determined the BRAF mutation frequency in a panel of 13 mucosal melanomas and compared those data with data from all currently published series of cutaneous melanomas. METHODS: BRAF exon 15 DNA from 13 archival primary mucosal melanomas (eight vulvar, four anorectal, and one laryngeal) was sequenced using intron-based primers. As archival DNA occasionally produces poor-quality template, results were confirmed with a TspRI restriction fragment length polymorphism (RFLP) that distinguishes wild-type BRAF from the common mutant form V599E. A binomial test was used to compare the mutation frequency in the mucosal melanomas with the published mutation frequency in cutaneous melanomas. RESULTS: None of the 13 mucosal melanomas in this series had an exon 15 BRAF mutation, as compared to 54/165 (33%) primary cutaneous melanomas with BRAF mutations in a compilation of all current published studies (p = 0.006). DISCUSSION: These data suggest that UV exposure, plays a role in the genesis of BRAF mutations in cutaneous melanoma, despite the absence of the characteristic C>T or CC>TT mutation signature associated with UV exposure, and suggests mechanisms other than pyrimidine dimer formation are important in UV-induced mutagenesis.

Trans- and cis-acting requirements for blastodermal expression of the head gap gene buttonhead.

The Drosophila gene buttonhead (btd) encodes a zinc-finger protein related to the human transcription factor Sp1. btd is expressed in the syncytial blastoderm embryo in a stripe covering the anlagen of the antennal, intercalary and mandibular head segments. btd has been characterized as a head gap gene, since these segments are deleted in btd mutant embryos. We report here that the cis-acting elements required for btd head stripe expression are contained in a 1 kb DNA fragment, located about 3 kb upstream of the promoter. The four maternal coordinate systems are necessary for correct btd head stripe expression, likely by acting through the 1 kb cis-acting control region. Expression of the btd head stripe depends on the anterior morphogen encoded by the gene bicoid (bcd). bcd-dependent activation also involves the activity of the morphogens of the posterior and dorsoventral systems, hunchback and dorsal, respectively, which act together to control the spatial limits of the expression domain. Finally, the terminal system takes part in the regulation of btd head stripe expression by enhancing activation at low levels of activity and repression at high levels of activity.

Synergy between the hunchback and bicoid morphogens is required for anterior patterning in Drosophila.

Anterior patterning of the Drosophila embryo is specified by the localized expression of the gap genes, which is controlled by the gradient of the maternal morphogen bicoid (bcd). Another maternal component, hunchback (hb), can substitute for bcd in the thorax and abdomen. Here we show that hb is required for bcd to execute all of its functions. Removal of both maternal and zygotic hb produces embryos with disrupted polarity that fail to express all known bcd target genes correctly. Proper expression of hb and the head gap genes requires synergistic activation by hb and bcd. We propose that it is the combined activity of bcd and hb, and not bcd alone, that forms the morphogenetic gradient that specifies polarity along the embryonic axis and patterns the embryo. bcd may be a newly acquired Drosophila gene, which is gradually replacing some of the functions performed by maternal hb in other species.

Finite element analysis of six endosseous implants.

Stress magnitudes and contours in bone surrounding six endosteal post-type dental implants were calculated by using the finite element method. Comparisons were made by using Branemark, Core-Vent, Denar, Miter, Stryker, and experimental implant designs. Although certain assumptions were made that could be considered controversial, this study concluded that apical "punching stresses" with all of the implants were probably not clinically significant. Saucerization resulting from biomechanical overloads could be a possibility for three of the implants. Problems related to combinations of overloads and underloads at the same time were suggested for several more popular implants in the United States. Additional research, combining 3-D finite element models and clinical studies, was recommended for all commercially available dental implants.

Finite element analysis of bone-adapted and bone-bonded endosseous implants.

The use of bioactive coatings on endosseous implants to induce bone bonding to the implants has become popular in recent years. The actual benefit from these coatings, however, remains controversial. This study compared three endosseous implants by using finite element analysis to determine whether bone-bonding or bone-adaptation (osseo-integration) was biomechanically more beneficial. Results indicated that although a bonded interface between an implant and its host tissues may be biochemically beneficial, bone bonding, by any means, may not be biomechanically beneficial to the implant or the surrounding bone. Neither clinicians nor manufacturers should assume that bioactive coatings or bone-bonding in general improve the biomechanical prognoses of endosteal postdental implants.

Alternative materials for three endosseous implants.

Three endosseous post-type implant geometries were evaluated: a serrated solid with a 2-degree taper and a rectangular cross section, a cylindrical screw-type solid, and a finned solid with a 1-degree 9' taper and a circular cross section. Each implant geometry was analyzed with 10 different moduli of elasticity. Stress contour plots were used to identify which implant material was best suited to each implant geometry. Careful examination of all of the contour plots showed that, for all geometries, increasing the material stiffness transmitted more of the occlusal load to the apical bone. These plots further suggested that an implant material can be too stiff as the punching stresses increase at the apex of the implant. Of the three endosseous implants analyzed, only the finned solid type seemed to be made of the proper material, titanium alloy. The screw-type implant, made of sapphire, should be made of aluminum or possibly titanium. The serrated implant, made of polycrystalline alumina, was too stiff. An implant's elastic behavior is not the only governing factor. An implant's geometry seems to be the determining factor in properly distributing stresses from the implant to the bone.

Submerged alumina dental root implants in humans: five-year evaluation.

This article describes the placement, success rate, and evaluation of an experimental alumina (Al2O3) ceramic dental implant at a mean placement time of 5 years. The study compared the longevity of a submerged implant of the same root design and a refined surgical technique with previously reported studies of the implant exposed to the human oral environment during initial healing. A 54% success rate was achieved for 29 implants placed in the maxillae and mandible, all restored with cast gold dental crowns. A significant difference (p = 0.05) appeared between success and failures at 7.8 months following placement. Crown/root ratio slopes were an earlier and more sensitive indicator of potential success or failure than the bone height slopes. Computer analysis revealed no apparent correlation between implant mobility and/or pocket depths and implant longevity. Delayed implant root fractures and a cast post fracture occurred in 20% of the implants that survived.

A precision alignment frame for endosseous post dental implants.

The advantages of the precision alignment frame are that it (1) accurately positions and aligns the initial pilot drill at implant surgery, (2) has no adverse effects on the diagnostic cast, (3) eliminates the need for an incision or raising a flap when locating a submerged implant root for transmucosal connection, (4) consistently and accurately records the relation of the implant root to the radiograph, (5) permits long-term evaluation of the implant after restoration, (6) has components that are readily obtainable and inexpensive, and (7) is easily made. With a PAF, accurate placement of an implant can be routinely achieved without drill alignment changes. This is especially important when multiple implants are being placed to support a long framework. In most implant sites, the PAF will record the entire image of the implant on the radiograph. However, patients with advanced alveolar bone resorption, flat or narrow vaults in the premaxilla, or high muscle attachments to the mandible may yield only a coronal image of the implant root on the radiograph. In those patients, the PAF is valuable in evaluating early bone healing and remodeling at the permucosal and neck areas.