Addition of ramucirumab or merestinib to standard first-line chemotherapy for locally advanced or metastatic biliary tract cancer: a randomised, double-blind, multicentre, phase 2 study.

BACKGROUND: Biliary tract cancers are aggressive, rare, gastrointestinal malignancies with a poor prognosis; approximately half of patients with these cancers survive for less than 1 year after diagnosis with advanced disease. We aimed to evaluate the efficacy and safety of ramucirumab or merestinib in addition to first-line cisplatin-gemcitabine in patients with locally advanced or metastatic biliary tract cancer. METHODS: We did a randomised, double-blind, phase 2 study at 81 hospitals across 18 countries. We enrolled patients with histologically or cytologically confirmed, non-resectable, recurrent, or metastatic biliary tract adenocarcinoma, who were treatment-naive, aged 18 years or older, with an Eastern Cooperative Oncology Group performance status of 0 or 1, estimated life expectancy of 3 months or more, and measurable disease per Response Evaluation Criteria in Solid Tumors version 1.1. Eligible participants were randomly assigned (2:1:2:1) to receive either intravenous ramucirumab 8 mg/kg or placebo (on days 1 and 8 in 21-day cycles) or oral merestinib 80 mg or placebo (once daily) until disease progression, unacceptable toxicity, death, or patient or investigator request for discontinuation. All participants received intravenous cisplatin 25 mg/m2 and gemcitabine 1000 mg/m2 (on days 1 and 8 in 21-day cycles), for a maximum of eight cycles. Randomisation was done by an interactive web response system using a permuted block method (blocks of six) and was stratified by primary tumour site, geographical region, and presence of metastatic disease. Participants, investigators, and the study funder were masked to treatment assignment within the intravenous and oral groups. The primary endpoint was investigator-assessed progression-free survival (in the intention-to-treat population). The safety analysis was done in all patients who received at least one dose of their assigned treatment. This trial is registered with ClinicalTrials.gov, NCT02711553, and long-term follow-up is ongoing. FINDINGS: Between May 25, 2016, and Aug 8, 2017, 450 patients were assessed for eligibility and 309 (69%) were enrolled and randomly assigned to ramucirumab (n=106), merestinib (n=102), or pooled placebo (n=101); 306 received at least one dose of study treatment. The median follow-up time for progression-free survival at data cutoff (Feb 16, 2018) was 10·9 months (IQR 8·1-14·1). Median progression-free survival was 6·5 months (80% CI 5·7-7·1) in the ramucirumab group, 7·0 months (6·2-7·1) in the merestinib group, and 6·6 months (5·6-6·8) in the pooled placebo group (ramucirumab vs placebo hazard ratio 1·12 [80% CI 0·90-1·40], two-sided stratified p=0·48; merestinib vs placebo 0·92 [0·73-1·15], two-sided stratified p=0·64). The most common grade 3 or worse adverse events were neutropenia (51 [49%] of 104 patients in the ramucirumab group; 48 [47%] of 102 in the merestinib group; and 33 [33%] of 100 in the pooled placebo group), thrombocytopenia (36 [35%]; 19 [19%]; and 17 [17%]), and anaemia (28 [27%]; 16 [16%]; and 19 [19%]). Serious adverse events occurred in 53 (51%) patients in the ramucirumab group, 56 (55%) in the merestinib group, and 48 (48%) in the pooled placebo group. Treatment-related deaths (deemed related by the investigator) occurred in one (1%) of 104 patients in the ramucirumab group (cardiac arrest) and two (2%) of 102 patients in the merestinib group (pulmonary embolism [n=1] and sepsis [n=1]). INTERPRETATION: Adding ramucirumab or merestinib to first-line cisplatin-gemcitabine was well tolerated, with no new safety signals, but neither improved progression-free survival in patients with molecularly unselected, locally advanced or metastatic biliary tract cancer. The role of these targeted inhibitors remains investigational, highlighting the need for further understanding of biliary tract malignancies and the contribution of molecular selection. FUNDING: Eli Lilly and Company.

c-Fos Repression by Piwi Regulates Drosophila Ovarian Germline Formation and Tissue Morphogenesis.

Drosophila melanogaster Piwi functions within the germline stem cells (GSCs) and the somatic niche to regulate GSC self-renewal and differentiation. How Piwi influences GSCs is largely unknown. We uncovered a genetic interaction between Piwi and c-Fos in the somatic niche that influences GSCs. c-Fos is a proto-oncogene that influences many cell and developmental processes. In wild-type ovarian cells, c-Fos is post-transcriptionally repressed by Piwi, which destabilized the c-Fos mRNA by promoting the processing of its 3' untranslated region (UTR) into Piwi-interacting RNAs (piRNAs). The c-Fos 3' UTR was sufficient to trigger Piwi-dependent destabilization of a GFP reporter. Piwi represses c-Fos in the somatic niche to regulate GSC maintenance and differentiation and in the somatic follicle cells to affect somatic cell disorganization, tissue dysmorphogenesis, oocyte maturation arrest, and infertility.

Whole-genome sequencing identifies genetic alterations in pediatric low-grade gliomas.

The most common pediatric brain tumors are low-grade gliomas (LGGs). We used whole-genome sequencing to identify multiple new genetic alterations involving BRAF, RAF1, FGFR1, MYB, MYBL1 and genes with histone-related functions, including H3F3A and ATRX, in 39 LGGs and low-grade glioneuronal tumors (LGGNTs). Only a single non-silent somatic alteration was detected in 24 of 39 (62%) tumors. Intragenic duplications of the portion of FGFR1 encoding the tyrosine kinase domain (TKD) and rearrangements of MYB were recurrent and mutually exclusive in 53% of grade II diffuse LGGs. Transplantation of Trp53-null neonatal astrocytes expressing FGFR1 with the duplication involving the TKD into the brains of nude mice generated high-grade astrocytomas with short latency and 100% penetrance. FGFR1 with the duplication induced FGFR1 autophosphorylation and upregulation of the MAPK/ERK and PI3K pathways, which could be blocked by specific inhibitors. Focusing on the therapeutically challenging diffuse LGGs, our study of 151 tumors has discovered genetic alterations and potential therapeutic targets across the entire range of pediatric LGGs and LGGNTs.

Methylation detection oligonucleotide microarray analysis: a high-resolution method for detection of CpG island methylation.

Methylation of CpG islands associated with genes can affect the expression of the proximal gene, and methylation of non-associated CpG islands correlates to genomic instability. This epigenetic modification has been shown to be important in many pathologies, from development and disease to cancer. We report the development of a novel high-resolution microarray that detects the methylation status of over 25,000 CpG islands in the human genome. Experiments were performed to demonstrate low system noise in the methodology and that the array probes have a high signal to noise ratio. Methylation measurements between different cell lines were validated demonstrating the accuracy of measurement. We then identified alterations in CpG islands, both those associated with gene promoters, as well as non-promoter-associated islands in a set of breast and ovarian tumors. We demonstrate that this methodology accurately identifies methylation profiles in cancer and in principle it can differentiate any CpG methylation alterations and can be adapted to analyze other species.

Genomic events associated with progression of pleural malignant mesothelioma.

Pleural malignant mesothelioma (MM) is an aggressive cancer with a very long latency and a very short median survival. Little is known about the genetic events that trigger MM and their relation to poor outcome. The goal of our study was to characterize major genomic gains and losses associated with MM origin and progression and assess their clinical significance. We performed Representative Oligonucleotide Microarray Analysis (ROMA) on DNA isolated from tumors of 22 patients who recurred at variable interval with the disease after surgery. The total number of copy number alterations (CNA) and frequent imbalances for patients with short time (<12 months from surgery) and long time to recurrence were recorded and mapped using the Analysis of Copy Errors algorithm. We report a profound increase in CNA in the short-time recurrence group with most chromosomes affected, which can be explained by chromosomal instability associated with MM. Deletions in chromosomes 22q12.2, 19q13.32 and 17p13.1 appeared to be the most frequent events (55-74%) shared between MM patients followed by deletions in 1p, 9p, 9q, 4p, 3p and gains in 5p, 18q, 8q and 17q (23-55%). Deletions in 9p21.3 encompassing CDKN2A/ARF and CDKN2B were characterized as specific for the short-term recurrence group. Analysis of the minimal common areas of frequent gains and losses identified candidate genes that may be involved in different stages of MM: OSM (22q12.2), FUS1 and PL6 (3p21.3), DNAJA1 (9p21.1) and CDH2 (18q11.2-q12.3). Imbalances seen by ROMA were confirmed by Affymetrix genome analysis in a subset of samples.

The evolution of selfing in Arabidopsis thaliana.

Unlike most of its close relatives, Arabidopsis thaliana is capable of self-pollination. In other members of the mustard family, outcrossing is ensured by the complex self-incompatibility (S) locus,which harbors multiple diverged specificity haplotypes that effectively prevent selfing. We investigated the role of the S locus in the evolution of and transition to selfing in A. thaliana. We found that the S locus of A. thaliana harbored considerable diversity, which is an apparent remnant of polymorphism in the outcrossing ancestor. Thus, the fixation of a single inactivated S-locus allele cannot have been a key step in the transition to selfing. An analysis of the genome-wide pattern of linkage disequilibrium suggests that selfing most likely evolved roughly a million years ago or more.