Mutation-driven epigenetic alterations as a defining hallmark of central cartilaginous tumours, giant cell tumour of bone and chondroblastoma.
- 作者列表："Venneker S","Szuhai K","Hogendoorn PCW","Bovée JVMG
:Recently, specific driver mutations were identified in chondroblastoma, giant cell tumour of bone and central cartilaginous tumours (specifically enchondroma and central chondrosarcoma), sharing the ability to induce genome-wide epigenetic alterations. In chondroblastoma and giant cell tumour of bone, the neoplastic mononuclear stromal-like cells frequently harbour specific point mutations in the genes encoding for histone H3.3 (H3F3A and H3F3B). The identification of these driver mutations has led to development of novel diagnostic tools to distinguish between chondroblastoma, giant cell tumour of bone and other giant cell containing tumours. From a biological perspective, these mutations induce several global and local alterations of the histone modification marks. Similar observations are made for central cartilaginous tumours, which frequently harbour specific point mutations in the metabolic enzymes IDH1 or IDH2. Besides an altered methylation pattern on histones, IDH mutations also induce a global DNA hypermethylation phenotype. In all of these tumour types, the mutation-driven epigenetic alterations lead to a highly altered transcriptome, resulting for instance in alterations in differentiation. These genomic alterations have diagnostic impact. Further research is needed to identify the genes and signalling pathways that are affected by the epigenetic alterations, which will hopefully lead to a better understanding of the biological mechanism underlying tumourigenesis.
: 最近，在软骨母细胞瘤、骨巨细胞瘤和中央软骨肿瘤 (特别是内生软骨瘤和中央软骨肉瘤) 中发现了特定的驱动突变，共享诱导全基因组表观遗传改变的能力。在软骨母细胞瘤和骨巨细胞瘤中，肿瘤性单核基质样细胞经常在编码组蛋白H3.3 (H3F3A和H3F3B) 的基因中存在特异性点突变。这些驱动突变的鉴定导致了新的诊断工具的开发，以区分软骨母细胞瘤、骨巨细胞瘤和其他含有巨细胞的肿瘤。从生物学角度来看，这些突变诱导组蛋白修饰标记的几个全局和局部改变。对中央软骨肿瘤也有类似的观察，这些肿瘤经常在代谢酶IDH1 或idh2 中存在特定的点突变。除了组蛋白上甲基化模式的改变，IDH突变也诱导了全局DNA高甲基化表型。在所有这些肿瘤类型中，突变驱动的表观遗传改变导致转录组高度改变，例如导致分化改变。这些基因组改变具有诊断影响。需要进一步的研究来确定受表观遗传改变影响的基因和信号通路，这将有望更好地理解肿瘤发生的生物学机制。
METHODS:OBJECTIVE:Large inoperable sacral chordomas show unsatisfactory local control rates even when treated with high dose proton therapy (PT). The aim of this study is assessing feasibility and reporting early results of patients treated with PT and concomitant hyperthermia (HT). METHODS: :Patients had histologically proven unresectable sacral chordomas and received 70 Gy (relative biological effectiveness) in 2.5 Gy fractions with concomitant weekly HT. Toxicity was assessed according to CTCAE_v4. A volumetric tumor response analysis was performed. RESULTS: :Five patients were treated with the combined approach. Median baseline tumor volume was 735 cc (range, 369-1142). All patients completed PT and received a median of 5 HT sessions (range, 2-6). Median follow-up was 18 months (range, 9-26). The volumetric analysis showed an objective response of all tumors (median shrinkage 46%; range, 9-72). All patients experienced acute Grade 2-3 local pain. One patient presented with a late Grade 3 iliac fracture. CONCLUSION:Combining PT and HT in large inoperable sacral chordomas is feasible and causes acceptable toxicity. Volumetric analysis shows promising early results, warranting confirmation in the framework of a prospective trial. ADVANCES IN KNOWLEDGE: :This is an encouraging first report of the feasibility and early results of concomitant HT and PT in treating inoperable sacral chordoma.
METHODS:BACKGROUND:National guidelines recommend screening and treatment for cancer-related bone disease and continued monitoring of bone-modifying agents. It is unclear whether a standardized screening tool is utilized to identify eligible patients and ensure appropriate supportive care is implemented. The purpose of this study was to evaluate current prescribing practices and optimize management of bone-modifying agents. METHODS:A retrospective chart review was performed to identify patients who received hormone deprivation therapy or had bone metastases through Hematology/Oncology or Urology clinics from 1 November 2016 to 31 October 2017. The primary endpoints of this study were the incidence of completed baseline dual-energy X-ray absorptiometry (DEXA) scan for patients on hormone deprivation therapy and percent of patients started on a bone-modifying agent for the prevention of skeletal-related events secondary to bone metastasis. Secondary endpoints included percent of patients with dental examinations prior to initiation, adequate calcium and vitamin D supplementation, incidence of osteonecrosis of the jaw or flu-like symptoms and education, and percent of bisphosphonate doses appropriately adjusted based on renal function. RESULTS:A total of 375 patients were assessed for baseline DEXA scans and bone-modifying therapy. Of the 226 patients on hormone deprivation therapy, 111 (49%) patients were appropriately screened with a DEXA scan prior to initiation of hormone deprivation therapy. Among the 149 patients with bone metastases, only 94 (63.1%) patients were started on a bone-modifying agent. CONCLUSIONS:Opportunities have been identified to optimize management of patients with cancer-related bone disease. Implementation of standardized tools may increase the rate of appropriate screening and initiation of bone-modifying therapy when warranted.
METHODS:PURPOSE:Low skeletal muscle mass has been associated with poor prognosis in patients with advanced lung cancer. However, little is known about the relationship between skeletal muscle mass and overall survival in patients with bone metastases from lung cancer. The objective of the present study was to evaluate the prognostic value of low trunk muscle mass in predicting overall survival in these patients. METHODS:The data from 198 patients who were diagnosed with bone metastases from lung cancer from April 2009 to May 2017 were retrospectively reviewed. The areas of the psoas and paravertebral muscles were measured at the level of the third lumbar vertebra on computed tomography scans taken at the time nearest to the diagnosis of bone metastasis. Muscle area was evaluated for male and female cohorts separately using different cutoff points. Cox proportional hazards analysis was performed to evaluate the factors independently associated with overall survival. RESULTS:The overall survival of patients in the lowest quartile for psoas muscle area or paravertebral muscle area was significantly shorter than that of patients above the 25th percentile for muscle area (p < 0.001). Multivariate analyses showed that paravertebral muscle mass (hazard ratio, 1.73; 95% confidence interval, 1.17-2.56; p = 0.006), epidermal growth factor receptor-targeted therapy, and performance status were independent prognostic factors. CONCLUSIONS:Low paravertebral muscle mass was associated with shorter survival, independently of known prognostic factors.