Department of Genetics, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands; Department of Anatomical Pathology, Universitas Gadjah Mada, Faculty of Medicine, Public Health, and Nursing / Dr. Sardjito Hospital, Yogyakarta, Indonesia.
Department of Pathology and Medical Biology, University of Groningen, University Medical Center Groningen, Groningen, the Netherlands.
Exp Mol Pathol. 2020 Aug;115:104431. doi: 10.1016/j.yexmp.2020.104431. Epub 2020 Apr 4.
Only a limited number of studies have explored the possible associations between tumour grade and mutated genes in clear cell renal cell carcinoma (ccRCC), and we set out to investigate this further using a multiple sampling and next generation sequencing (NGS) approach in a series of ccRCCs. Multiple regions were sampled from formalin-fixated paraffin-embedded ccRCC tumour blocks from seven patients. In 27 samples from six patients, we performed targeted NGS using a custom 42-gene panel based on the most frequently mutated genes in ccRCC reported in public databases. In four samples from the seventh patient, we performed whole exome sequencing (WES) and array comparative genomic hybridisation for detection of copy number variants (CNVs). Mutated genes and the tumour grades of the samples in which they had been identified were compared both within and between all individual tumours. CNVs were compared across all samples from patient 7. We identified clear genetic heterogeneity within and across tumours, but VHL mutations were seen in all patients. Looking across all samples, we identified eleven genes that were only mutated in samples with one particular tumour grade. However, these genes were never mutated in all samples with that tumour grade. Increasing chromosomal instability corresponded with increasing tumour grade, but we observed minimal association between tumour grade and total mutational load in the WES data. Our study confirms the genetic heterogeneity and tumour grade heterogeneity of ccRCC. Although a relatively small number of samples was analysed, genes were identified that could potentially be specific, though insensitive, markers of higher ccRCC tumour grades.
仅有少数研究探索了透明细胞肾细胞癌（ccRCC）中肿瘤分级与突变基因之间的可能关联，我们使用多区域取样和下一代测序（NGS）方法在一系列 ccRCC 中进一步研究了这一点。从 7 名患者的福尔马林固定石蜡包埋 ccRCC 肿瘤块中多个区域取样。在 6 名患者的 27 个样本中，我们使用基于公共数据库中报道的 ccRCC 中最常见突变基因的定制 42 基因面板进行靶向 NGS。在第 7 名患者的 4 个样本中，我们进行了全外显子组测序（WES）和基于阵列的比较基因组杂交，以检测拷贝数变异（CNVs）。比较了在所有个体肿瘤内和之间发现突变基因和样本的肿瘤分级。在患者 7 的所有样本中比较了 CNVs。我们在肿瘤内和肿瘤之间发现了明显的遗传异质性，但所有患者均存在 VHL 突变。纵观所有样本，我们发现有 11 个基因仅在特定肿瘤分级的样本中发生突变。然而，这些基因从未在所有具有该肿瘤分级的样本中发生突变。染色体不稳定性增加与肿瘤分级增加相关，但我们在 WES 数据中观察到肿瘤分级与总突变负荷之间的关联最小。我们的研究证实了 ccRCC 的遗传异质性和肿瘤分级异质性。尽管分析的样本数量相对较少，但鉴定出的基因可能是特定的、尽管不敏感的高 ccRCC 肿瘤分级的标志物。
