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Accurate modeling of intratumor heterogeneity presents a bottleneck against drug testing. Flexibility in a preclinical platform is also desirable to support assessment of different endpoints. We established the model system, OHC-NB1, from a bone marrow metastasis from a patient diagnosed with MYCN-amplified neuroblastoma and performed whole-exome sequencing on the source metastasis and the different models and passages during model development (monolayer cell line, 3D spheroid culture and subcutaneous xenograft tumors propagated in mice). OHC-NB1 harbors a MYCN amplification in double minutes, 1p deletion, 17q gain and diploid karyotype, which persisted in all models. A total of 80–540 single-nucleotide variants (SNVs) was detected in each sample, and comparisons between the source metastasis and models identified 34 of 80 somatic SNVs to be propagated in the models. Clonal reconstruction using the combined copy number and SNV data revealed marked clonal heterogeneity in the originating metastasis, with four clones being reflected in the model systems. The set of OHC-NB1 models represents 43% of somatic SNVs and 23% of the cellularity in the originating metastasis with varying clonal compositions, indicating that heterogeneity is partially preserved in our model system.  相似文献   
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Familial Cancer - In high-risk individuals participating in a pancreatic cancer surveillance program, worrisome features warrant for intensified surveillance or, occasionally, surgery. Our...  相似文献   
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Iris Cervenka  Marie Al Rahmoun  Yahya Mahamat-Saleh  Agnès Fournier  Marie-Christine Boutron-Ruault  Gianluca Severi  Saverio Caini  Domenico Palli  Reza Ghiasvand  Marit B. Veierod  Edoardo Botteri  Anne Tjønneland  Anja Olsen  Renée T. Fortner  Rudolf Kaaks  Matthias B. Schulze  Salvatore Panico  Antonia Trichopoulou  Clio Dessinioti  Katerina Niforou  Sabina Sieri  Rosario Tumino  Carlotta Sacerdote  Bas Bueno-de-Mesquita  Torkjel M. Sandanger  Sandra Colorado-Yohar  Maria J. Sánchez  Leire Gil Majuelo  Leila Lujan-Barroso  Eva Ardanaz  Susana Merino  Karolin Isaksson  Salma Butt  Ingrid Ljuslinder  Malin Jansson  Ruth C. Travis  Kay-Tee Khaw  Elisabete Weiderpass  Laure Dossus  Sabina Rinaldi  Marina Kvaskoff 《International journal of cancer. Journal international du cancer》2020,146(12):3267-3280
Evidence suggests an influence of sex hormones on cutaneous melanoma risk, but epidemiologic findings are conflicting. We examined the associations between use of oral contraceptives (OCs) and menopausal hormone therapy (MHT) and melanoma risk in women participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). EPIC is a prospective cohort study initiated in 1992 in 10 European countries. Information on exogenous hormone use at baseline was derived from country-specific self-administered questionnaires. We used Cox proportional hazards regression models to calculate hazard ratios (HRs) and 95% confidence intervals (CIs). Over 1992–2015, 1,696 melanoma cases were identified among 334,483 women, whereof 770 cases among 134,758 postmenopausal women. There was a positive, borderline-significant association between OC use and melanoma risk (HR = 1.12, 95% CI = 1.00–1.26), with no detected heterogeneity across countries (phomogeneity = 0.42). This risk increased linearly with duration of use (ptrend = 0.01). Among postmenopausal women, ever use of MHT was associated with a nonsignificant increase in melanoma risk overall (HR = 1.14, 95% CI = 0.97–1.43), which was heterogeneous across countries (phomogeneity = 0.05). Our findings do not support a strong and direct association between exogenous hormone use and melanoma risk. In order to better understand these relations, further research should be performed using prospectively collected data including detailed information on types of hormone, and on sun exposure, which may act as an important confounder or effect modifier on these relations.  相似文献   
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Background

Symptoms at suspicion of necrotizing enterocolitis (NEC) are often nonspecific and several biomarkers have been evaluated for their discriminative power to both diagnose and predict the course from NEC suspicion to complicated disease requiring surgical intervention. Thus, we aimed to assess the utility of interleukin-6 (IL-6) to predict surgical intervention in infants suffering from NEC and, furthermore, to discriminate infants with starting NEC or late-onset sepsis (LOS).

Methods

IL-6 serum levels at disease onset were retrospectively analyzed in 24 infants suffering from NEC as well as 16 neonates with LOS.

Results

IL-6 serum levels at disease onset were significantly higher in infants suffering from NEC necessitating surgical intervention in the disease course compared to infants with medical NEC (5000 [785–5000] vs. 370 [78–4716] pg/ml, p?=?0.0008) as well as gram-positive LOS (5000 [785–5000] vs. 84 [12–269] pg/ml, p?=?0.0001). Infants suffering from gram-negative LOS exhibited elevated IL-6 serum levels at disease onset comparable to infants with surgical NEC (5000 [1919–5000] vs. 5000 [785–5000] pg/ml, p?=?1.00).

Conclusion

The proinflammatory cytokine IL-6 appears to be a promising marker to distinguish surgical NEC from medical NEC at the onset of disease but cannot discriminate between surgical NEC and gram-negative LOS.

Level of evidence

II  相似文献   
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