In multiple myeloma malignant plasma cells expand within the bone marrow. Since this site is well-perfused, a rapid dissemination of “fitter” clones may be anticipated. However, an imbalanced distribution of multiple myeloma is frequently observed in medical imaging. Here, we perform multi-region sequencing, including iliac crest and radiology-guided focal lesion specimens from 51 patients to gain insight into the spatial clonal architecture. We demonstrate spatial genomic heterogeneity in more than 75% of patients, including inactivation of CDKN2C and TP53, and mutations affecting mitogen-activated protein kinase genes. We show that the extent of spatial heterogeneity is positively associated with the size of biopsied focal lesions consistent with regional outgrowth of advanced clones. The results support a model for multiple myeloma progression with clonal sweeps in the early phase and regional evolution in advanced disease. We suggest that multi-region investigations are critical to understanding intra-patient heterogeneity and the evolutionary processes in multiple myeloma.
• Hits in driver genes and bi-allelic events affecting tumor suppressors increase apoptosis resistance and proliferation rate-driving relapse.• Excessive biallelic inactivation of tumor suppressors in highrisk cases highlights the need for TP53-independent therapeutic approaches.To elucidate the mechanisms underlying relapse from chemotherapy in multiple myeloma, we performed a longitudinal study of 33 patients entered into Total Therapy protocols investigating them using gene expression profiling, high-resolution copy number arrays, and whole-exome sequencing. The study illustrates the mechanistic importance of acquired mutations in known myeloma driver genes and the critical nature of biallelic inactivation events affecting tumor suppressor genes, especially TP53, the end result being resistance to apoptosis and increased proliferation rates, which drive relapse by Darwinian-type clonal evolution. The number of copy number aberration changes and biallelic inactivation of tumor suppressor genes was increased in GEP70 high risk, consistent with genomic instability being a key feature of high risk. In conclusion, the study highlights the impact of acquired genetic events, which enhance the evolutionary fitness level of myeloma-propagating cells to survive multiagent chemotherapy and to result in relapse. (Blood. 2016;128(13):1735-1744
Neglect in acute stroke is an important predictor of poor functional recovery. Residual neglect, which could be compensated in the follow-up tests, may nevertheless restrict patients' real-life activities and hobbies.
Background and Purpose-Oxidative stress is probably involved in neuronal damage induced by ischemia-reperfusion.The purpose of this study was to assess the role of antioxidant activity in cerebral ischemic stroke. Methods-Antioxidant activity of blood plasma and cerebrospinal fluid was assessed in 22 patients with cerebral hemisphere infarction that was verified and quantified by MRI. Results-Low total peroxyl radical trapping potential of plasma, but not of cerebrospinal fluid, was associated with high lesion volume and high neurological impairment assessed by scores on NIH Stroke Scale, Barthel Index, and Hand Motor Score tests. The plasma concentrations of ascorbic acid, ␣-tocopherol, and protein thiols were also associated with the degree of neurological impairment. Conclusions-These data suggest that the antioxidant activity of plasma may be an important factor providing protection from neurological damage caused by stroke-associated oxidative stress. (Stroke. 2000;31:33-39.)
Hemiparesis, unawareness of illness and presence of a relative at home were the best predictors of the time from right hemisphere stroke to discharge to home.
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