Optical Control of Tumor Induction in the Zebrafish

International audienceThe zebrafish has become an increasingly popular and valuable cancer model over the past few decades. While most zebrafish cancer models are generated by expressing mammalian oncogenes under tissue-specific promoters, here we describe a method that allows for the precise optical control of oncogene expression in live zebrafish. We utilize this technique to transiently or constitutively activate a typical human oncogene, kRASG12V, in zebrafish embryos and investigate the developmental and tumorigenic phenotypes. We demonstrate the spatiotemporal control of oncogene expression in live zebrafish, and characterize the different tumorigenic probabilities when kRASG12V is expressed transiently or constitutively at different developmental stages. Moreover, we show that light can be used to activate oncogene expression in selected tissues and single cells without tissue-specific promoters. Our work presents a novel approach to initiate and study cancer in zebrafish, and the high spatiotemporal resolution of this method makes it a valuable tool for studying cancer initiation from single cells

Optical Control of Tumor Induction in the Zebrafish.

The zebrafish has become an increasingly popular and valuable cancer model over the past few decades. While most zebrafish cancer models are generated by expressing mammalian oncogenes under tissue-specific promoters, here we describe a method that allows for the precise optical control of oncogene expression in live zebrafish. We utilize this technique to transiently or constitutively activate a typical human oncogene, kRASG12V, in zebrafish embryos and investigate the developmental and tumorigenic phenotypes. We demonstrate the spatiotemporal control of oncogene expression in live zebrafish, and characterize the different tumorigenic probabilities when kRASG12V is expressed transiently or constitutively at different developmental stages. Moreover, we show that light can be used to activate oncogene expression in selected tissues and single cells without tissue-specific promoters. Our work presents a novel approach to initiate and study cancer in zebrafish, and the high spatiotemporal resolution of this method makes it a valuable tool for studying cancer initiation from single cells

Advances and Concepts in Cervical Cancer Trials: A Road Map for the Future.

ObjectiveCervical cancer is responsible for more than a quarter of a million deaths globally each year, mostly in developing countries, making therapeutic advances in all health care settings a top priority. The Gynecologic Cancer InterGroup (GCIG) is a worldwide collaboration of leading national research groups that develops and promotes multinational trials in gynecologic cancer. In recognition of the pressing need for action, the GCIG convened an international meeting with expert representation from the GCIG groups and selected large sites in low- and middle-income countries.MethodsThe focus was to develop a consensus on several concepts for future clinical trials, which would be developed and promoted by the GCIG and launched with major international participation. The first half of the meeting was devoted to a resume of the current state of the knowledge and identifying the gaps in need of new evidence, validating control arms for present and future clinical trials and identifying national and international barriers for studies of cervix cancers. The second half of the meeting was concerned with achieving consensus on a path forward.Results and ConclusionsThere were 5 principal outcomes as follows: first, a proposal to expand fertility-preserving options with neoadjuvant chemotherapy; second, validation of the assessment of sentinel lymph nodes using minimally invasive surgery with an emphasis on identification and management of low-volume metastasis, such as isolated tumor cells and micrometastasis; third, evaluation of hypofractionation for palliative and curative radiation under the umbrella of the GCIG Cervix Cancer Research Network; fourth, adding to the advances in antiangiogenesis therapy in the setting of metastatic disease; and fifth, developing a maintenance study among women at high risk of relapse. The latter 2 systemic interventions could study PI3K (phosphatidylinositol-3-kinase) inhibitors, immunotherapy, anti–human papillomavirus approaches, or novel antiangiogenic agents/combinations.</jats:sec

Survival outcomes of breast cancer patients with brain metastases: A multicenter retrospective study in Korea (KROG 16-12)

Purpose: This study evaluated the influence of prognostic factors and whole brain radiotherapy (WBRT) on overall survival (OS) of breast cancer (BC) patients with brain metastases (BM). Methods and materials: Medical records of 730 BC patients diagnosed with BM from 2000 to 2014 at 17 institutions were retrospectively reviewed. OS was calculated from BM diagnosis. Median follow-up duration was 11.9 months (range, 0.1-126.2). Results: Median OS was 15.0 months (95% CI: 14.0-16.9). Patients with different BC-specific graded prognostic assessment (GPA) scores showed significant differences (p 4; p = 0.002), hormone receptor negativity (p = 0.005), HER2-negativity (p = 0.003), and shorter time interval (0.673) subgroups; the high-risk subgroup had poorer median OS (10.1 months, 95% CI: 7.9-11.9 vs. 21.9 months, 95% CI: 19.5 -27.1, p = 30 months after BC diagnosis (n = 389, "late BM") revealed that WBRT-treated patients showed superior OS compared to non-WBRT-treated patients (p = 0.070 and 0.030, respectively). Conclusion: Our prognostic model identified high-risk BC patients with BM who might benefit from increased surveillance; if validated, our model could guide treatment selection for such patients. Patients with late BM might benefit from WBRT as initial local treatment. (C) 2019 Elsevier Ltd

The Pattern of Care for Brain Metastasis from Breast Cancer Over the Past 10 Years in Korea: A Multicenter Retrospective Study (KROG 16-12)

Purpose We aimed to investigate manifestations and patterns of care for patients with brain metastasis (BM) from breast cancer (BC) and compared their overall survival (OS) from 2005 through 2014 in Korea. Materials and Methods We retrospectively reviewed 600 BC patients with BM diagnosed between 2005 and 2014. The median follow-up duration was 12.5 months. We categorized the patients into three groups according to the year when BM was initially diagnosed (group I [2005-2008], 98 patients; group II [2009-2011], 200 patients; and group III [2012-2014], 302 patients). Results Over time, the median age at BM diagnosis increased by 2.2 years (group I, 49.0 years; group II, 48.3 years; and group III, 51.2 years; p=0.008). The percentage of patients with extracranial metastasis was 73.5%, 83.5%, and 86.4% for group I, II, and III, respectively (p=0.011). The time interval between BC and BM was prolonged in patients with stage III primary BC (median, 2.4 to 3 years; p=0.029). As an initial brain-directed treatment, whole-brain radiotherapy alone decreased from 80.0% in 2005 to 41.1% in 2014. Meanwhile, stereotactic radiosurgery or fractionated stereotactic radiotherapy alone increased from 13.3% to 34.7% during the same period (p=0.005). The median OS for group I, II, and III was 15.6, 17.9, and 15.0 months, respectively, with no statistical significance. Conclusion The manifestations of BM from BC and the pattern of care have changed from 2005 to 2014 in Korea. However, the OS has remained relatively unchanged over the 10 years.Y