Search

Background Several relatively large studies have assessed molecular indicators of colorectal cancer (CRC) prognosis, but most analyses have been restricted to a handful of markers. Methods In stage II/III CRCs from the QUASAR2 clinical trial and from an Australian community-based series, we assessed gene panels for somatic driver mutations and overall mutation burden. We determined molecular pathways of tumorigenesis, and analysed associations with treatment response and prognosis. Findings In QUASAR2 (N=511), TP53, KRAS, BRAF and GNAS mutations were independently associated with shorter relapse-free survival, whereas total somatic mutation burden was associated with longer survival, even after excluding mismatch repair-deficient (MSI+) and POLE-mutant tumours. We successfully validated these associations in the Australian sample set (N=296). In an extended analysis of 1,752 QUASAR2 and Australian CRCs for which KRAS, BRAF and MSI status was available, we found that KRAS and BRAF mutations were specifically associated with poor prognosis in MSI- cancers. This association was not present in MSI+ cancers, and MSI+ tumours with KRAS or BRAF mutation actually had better prognosis than MSI- cancers that were wildtype for KRAS or BRAF. New rare molecular pathways were also uncovered: mutations in the genes NF1 and NRAS from the MAP kinase pathway co-occurred, mutations in TP53 and ATM appeared to be alternative ways of inactivating the DNA damage response pathway. Interpretation A multi-gene panel has identified two previously unreported prognostic associations in CRC involving both TP53 mutation and total mutation burden, and confirmed associations with KRAS and BRAF. We conclude that even a modest-sized gene panel can provide important information for use in clinical practice and out-perform MSI-based models.

Rationale: C5aR1 (CD88), a receptor for complement anaphylatoxin C5a, is a potent immune mediator. Its impact on malignant growth and dissemination of non-small cell lung cancer cells is poorly understood. Objectives: To investigate the contribution of the C5a/C5aR1 axis to the malignant phenotype of non-small cell lung cancer cells, particularly in skeletal colonization, a preferential lung metastasis site. Methods: Association between C5aR1 expression and clinical outcome was assessed in silico and validated by immunohistochemistry. Functional significance was evaluated by lentiviral gene silencing and ligand L-aptamer inhibition in in vivo models of lung cancer bone metastasis. In vitro functional assays for signaling, migration, invasion, metalloprotease activity, and osteoclastogenesis were also performed. Measurements and Main Results: High levels of C5aR1 in human lung tumors were significantly associated with shorter recurrence-free survival, overall survival, and bone metastasis. Silencing of C5aR1 in lung cancer cells led to a substantial reduction in skeletal metastatic burden and osteolysis in in vivo models. Furthermore, metalloproteolytic, migratory, and invasive tumor cell activities were modulated in vitro by C5aR1 stimulation or gene silencing. L-Aptamer blockade or C5aR1 silencing significantly reduced the osseous metastatic activity of lung cancer cells in vivo. This effect was associated with decreased osteoclastogenic activity in vitro and was rescued by the exogenous addition of the chemokine CXCL16. Conclusions: Disruption of C5aR1 signaling in lung cancer cells abrogates their tumor-associated osteoclastogenic activity, impairing osseous colonization. This study unveils the role played by the C5a/C5aR1 axis in lung cancer dissemination and supports its potential use as a novel therapeutic target.

Sweet syndrome is a neutrophilic infiltration of the papillary dermis, which may be associated with the presence of unknown malignancies, either haematological or solid tumours, in 1 out of 5 cases, being considered then as a paraneoplastic syndrome. We present the case of a male with a locally advanced gastric cancer whose final diagnosis was led by the prior debut of Sweet syndrome not explained by other causes.

Background: Reported prevalence of driver gene mutations in non-small-cell lung cancer (NSCLC) is highly variable and clinical correlations are emerging. Using NSCLC biomaterial and clinical data from the European Thoracic Oncology Platform Lungscape iBiobank, we explore the epidemiology of mutations and association to clinicopathologic features and patient outcome (relapse-free survival, time-to-relapse, overall survival). Methods: Clinically annotated, resected stage I-III NSCLC FFPE tissue was assessed for gene mutation using a microfluidicsbased multiplex PCR platform. Mutant-allele detection sensitivity is>1% for most of the 150 (13 genes) mutations covered in the multiplex test. Results: Multiplex testing has been carried out in 2063 (76.2%) of the 2709 Lungscape cases (median follow-up 4.8 years). FFPE samples mostly date from 2005 to 2008, yet recently extracted DNA quality and quantity was generally good. Average DNA yield/case was 2.63 mg; 38 cases (1.4%) failed QC and were excluded from study; 95.1% of included cases allowed the complete panel of mutations to be tested. Most common were KRAS, MET, EGFR and PIK3CA mutations with overall prevalence of 23.0%, 6.8%, 5.4% and 4.9%, respectively. KRAS and EGFR mutations were significantly more frequent in adenocarcinomas: PIK3CA in squamous cell carcinomas. MET mutation prevalence did not differ between histology groups. EGFR mutations were found predominantly in never smokers; KRAS in current/former smokers. For all the above mutations, there was no difference in outcome between mutated and non-mutated cases. Conclusion: Archival FFPE NSCLC material is adequate for multiplex mutation analysis. In this large, predominantly European, clinically annotated stage I-III NSCLC cohort, none of the mutations characterized showed prognostic significance. © The Author 2017.

Chuvash polycythemia is an autosomal recessive form of erythrocytosis associated with a homozygous p.Arg200Trp mutation in the von Hippel-Lindau (VHL) gene. Since this discovery, additional VHL mutations have been identified in patients with congenital erythrocytosis, in a homozygous or compound-heterozygous state. VHL is a major tumor suppressor gene, mutations in which were first described in patients presenting with VHL disease, which is characterized by the development of highly vascularized tumors. Here, we identify a new VHL cryptic exon (termed E19) deep in intron 1 that is naturally expressed in many tissues. More importantly, we identify mutations in E19 in 7 families with erythrocytosis (1 homozygous case and 6 compound-heterozygous cases with a mutation in E19 in addition to a mutation in VHL coding sequences) and in 1 large family with typical VHL disease but without any alteration in the other VHL exons. In this study, we show that the mutations induced a dysregulation of VHL splicing with excessive retention of E19 and were associated with a downregulation of VHL protein expression. In addition, we demonstrate a pathogenic role for synonymous mutations in VHL exon 2 that altered splicing through E2-skipping in 5 families with erythrocytosis or VHL disease. In all the studied cases, the mutations differentially affected splicing, correlating with phenotype severity. This study demonstrates that cryptic exon retention and exon skipping are new VHL alterations and reveals a novel complex splicing regulation of the VHL gene. These findings open new avenues for diagnosis and research regarding the VHL-related hypoxia-signaling pathway. © 2018 by The American Society of Hematology.

Introduction: The reported prevalence of ALK receptor tyrosine kinase gene (ALK) rearrangement in NSCLC ranges from 2% to 7%. The primary standard diagnostic method is fluorescence in situ hybridization (FISH). Recently, immunohistochemistry (IHC) has also proved to be a reproducible and sensitive technique. Reverse-transcriptase polymerase chain reaction (RT-PCR) has also been advocated, and most recently, the advent of targeted next-generation sequencing (NGS) for ALK and other fusions has become possible. This study compares anaplastic lymphoma kinase (ALK) evaluation with all four techniques in resected NSCLC from the large European Thoracic Oncology Platform Lungscape cohort. Methods: A total of 96 cases from the European Thoracic Oncology Platform Lungscape iBiobank, with any ALK immunoreactivity were examined by FISH, central RT-PCR, and NGS. An H-score higher than 120 defines IHC positivity. RNA was extracted from the same formalin-fixed, paraffin-embedded tissues. For RT-PCR, primers covered the most frequent ALK translocations. For NGS, the Oncomine Solid Tumour Fusion Transcript Kit (Thermo Fisher Scientific, Waltham, MA) was used. The concordance was assessed using the Cohen κ coefficient (two-sided α ≤ 5%). Results: NGS provided results for 77 of the 95 cases tested (81.1%), whereas RT-PCR provided results for 77 of 96 (80.2%). Concordance occurred in 55 cases of the 60 cases tested with all four methods (43 ALK negative and 12 ALK positive). Using ALK copositivity for IHC and FISH as the criterion standard, we derived a sensitivity for RT-PCR/NGS of 70.0%/85.0%, with a specificity of 87.1%/79.0%. When either RT-PCR or NGS was combined with IHC, the sensitivity remained the same, whereas the specificity increased to 88.7% and 83.9% respectively. Conclusion: NGS evaluation with the Oncomine Solid Tumour Fusion transcript kit and RT-PCR proved to have high sensitivity and specificity, advocating their use in routine practice. For maximal sensitivity and specificity, ALK status should be assessed by using two techniques and a third one in discordant cases. We therefore propose a customizable testing algorithm. These findings significantly influence existing testing paradigms and have clear clinical and economic impact. © 2017 International Association for the Study of Lung Cancer