Molecular profiling of single circulating tumor cells with diagnostic intention

Several hundred clinical trials currently explore the role of circulating tumor cell (CTC) analysis for therapy decisions, but assays are lacking for comprehensive molecular characterization of CTCs with diagnostic precision. We therefore combined a workflow for enrichment and isolation of pure CTCs with a non-random whole genome amplification method for single cells and applied it to 510 single CTCs and 189 leukocytes of 66 CTC-positive breast cancer patients. We defined a genome integrity index (GII) to identify single cells suited for molecular characterization by different molecular assays, such as diagnostic profiling of point mutations, gene amplifications and whole genomes of single cells. The reliability of >90% for successful molecular analysis of high-quality clinical samples selected by the GII enabled assessing the molecular heterogeneity of single CTCs of metastatic breast cancer patients. We readily identified genomic disparity of potentially high relevance between primary tumors and CTCs. Microheterogeneity analysis among individual CTCs uncovered pre-existing cells resistant to ERBB2-targeted therapies suggesting ongoing microevolution at late-stage disease whose exploration may provide essential information for personalized treatment decisions and shed light into mechanisms of acquired drug resistance

Molecular profiling of single circulating tumor cells with diagnostic intention

Several hundred clinical trials currently explore the role of circulating tumor cell (CTC) analysis for therapy decisions, but assays are lacking for comprehensive molecular characterization of CTCs with diagnostic precision. We therefore combined a workflow for enrichment and isolation of pure CTCs with a non-random whole genome amplification method for single cells and applied it to 510 single CTCs and 189 leukocytes of 66 CTC-positive breast cancer patients. We defined a genome integrity index (GII) to identify single cells suited for molecular characterization by different molecular assays, such as diagnostic profiling of point mutations, gene amplifications and whole genomes of single cells. The reliability of >90% for successful molecular analysis of high-quality clinical samples selected by the GII enabled assessing the molecular heterogeneity of single CTCs of metastatic breast cancer patients. We readily identified genomic disparity of potentially high relevance between primary tumors and CTCs. Microheterogeneity analysis among individual CTCs uncovered pre-existing cells resistant to ERBB2-targeted therapies suggesting ongoing microevolution at late-stage disease whose exploration may provide essential information for personalized treatment decisions and shed light into mechanisms of acquired drug resistance

Impact of Climate Change on Voltinism and Prospective Diapause Induction of a Global Pest Insect – Cydia pomonella (L.)

Global warming will lead to earlier beginnings and prolongation of growing seasons in temperate regions and will have pronounced effects on phenology and life-history adaptation in many species. These changes were not easy to simulate for actual phenologies because of the rudimentary temporal (season) and spatial (regional) resolution of climate model projections. We investigate the effect of climate change on the regional incidence of a pest insect with nearly worldwide distribution and very high potential for adaptation to season length and temperature – the Codling Moth, Cydia pomonella. Seasonal and regional climate change signals were downscaled to the hourly temporal scale of a pest phenology model and the spatial scale of pest habitats using a stochastic weather generator operating at daily scale in combination with a re-sampling approach for simulation of hourly weather data. Under future conditions of increased temperatures (2045–2074), the present risk of below 20% for a pronounced second generation (peak larval emergence) in Switzerland will increase to 70–100%. The risk of an additional third generation will increase from presently 0–2% to 100%. We identified a significant two-week shift to earlier dates in phenological stages, such as overwintering adult flight. The relative extent (magnitude) of first generation pupae and all later stages will significantly increase. The presence of first generation pupae and later stages will be prolonged. A significant decrease in the length of overlap of first and second generation larval emergence was identified. Such shifts in phenology may induce changes in life-history traits regulating the life cycle. An accordingly life-history adaptation in photoperiodic diapause induction to shorter day-length is expected and would thereby even more increase the risk of an additional generation. With respect to Codling Moth management, the shifts in phenology and voltinism projected here will require adaptations of plant protection strategies to maintain their sustainability

Retinoblastoma pediátrico - visão geral / Pediatric retinoblastoma - overview

Introdução: o retinoblastoma é a malignidade primária intraocular mais comum na infância, contribuindo com 11% dos diagnósticos no primeiro ano de vida. O bom prognóstico depende de uma rápida detecção, seguida de sua classificação e tratamento precoce. Assim o presente trabalho tem por objetivo explicar as diversas características do retinoblastoma pediátrico, como: (1) epidemiologia, (2) fisiopatologia, (3) sinais e sintomas, (4) diagnóstico, (5) tratamento e (6) prognóstico. Metodologia: foi realizado uma revisão da literatura no pubmed/medline, usando os descritores “retinoblastoma and pediatric or retinoblastoma and epidemiology or retinoblastoma and signs and symptoms or retinoblastoma and diagnosis or retinoblastoma and treatment or retinoblastoma and prognosis” e os filtros de busca apenas revisões, revisões sistemáticas e metanálises, últimos 5 anos, os idiomas inglês, português e espanhol e a faixa etária até 18 anos. Resultados: após a pesquisa bibliográfica, foram incluídos 10 artigos. Discussão: (1) sua incidência gira em torno de 1 caso entre 15.000 para 18.000 nascidos vivos; (2) o retinoblastoma é uma malignidade associada a mutações no gene supressor de tumor rb1 localizado no braço longo do cromossomo 13 (13q14); (3) o sinal e sintoma mais comum é a leucocoria; (4) os exames mais utilizados para o seu diagnóstico são ultrassonografia, angiografia fluoresceínica, tomografia de coerência óptica, tomografia computadorizada e ressonância magnética; (5) o tratamento mais utilizado é feito com base na classificação internacional do retinoblastoma, sendo os casos divididos em 4 grupos (a,b,c e d). Os grupos a e b devem ser tratados com procedimentos locais, já os grupos c e d são tratados com a quimioterapia sistêmica ou a quimioterapia local intra-arterial ou intravítrea; (6) a doença apresenta uma taxa de cura elevada, com sobrevida de 98% dos casos. Conclusão: a identificação precoce junto a um tratamento adequado a sua classificação, torna o prognóstico muito favorável