Clonal evolution and molecular stratification of urothelial carcinoma in situ of the urinary bladder

膀胱癌是一种异质性疾病，具有不同的临床和肿瘤学过程。尿路上皮原位癌（CIS）是一种侵袭性的前浸润性尿路上皮内病变，是大多数预后不良的肌层浸润性膀胱癌的起源。到目前为止，CIS的分子演变还没有得到充分的理解，也不可能预测哪些CIS患者将有稳定的疾病，可以用保守的膀胱灌注治疗，以及哪些患者组将进展并可能受益于早期膀胱灌注。此外，一线治疗，即膀胱内滴注卡介苗（BCG），在超过50%的病例中由于毒性或治疗抵抗而失败，二线治疗根治性环磷酰胺导致可能的过度治疗并导致严重的生活方式后果。因此，在这项建议中，我们的目标是通过执行多区域的全外显子组测序方法，最初在冷冻保存的，完全包埋的膀胱癌标本含有CIS破译尿路上皮CIS的遗传景观。我们将利用生物信息学分析CIS的克隆异质性和进化，以了解基本的疾病发展及其动力学，并推导出治疗分层的相关信息，以及确定有希望进行有效靶向治疗的遗传事件。将在体外模型中功能性评估潜在的可药物化CIS改变的推定预测和治疗影响。基于这样的假设，即一个更多样化的肿瘤能够更有效地适应不断变化的环境条件，导致更快的肿瘤生长和进展，我们的目标是确定患者间的CIS内遗传多样性措施作为独立的预后分层（膀胱内治疗与根治性化疗）的一个强大的标准的适用性。在随后的项目中，我们的目标是验证我们目前正在建立的纵向活检队列中CIS风险分层的基本结果。

Bladder cancer is a heterogeneous disease with divergent clinical and oncological courses. Urothelial carcinoma in situ (CIS) is the aggressive pre-invasive intraurothelial lesion, from which the majority of muscle-invasive bladder carcinomas with poor prognosis arises. So far, neither the molecular evolution of CIS is sufficiently understood, nor is it possible to predict which CIS patients will have stable disease that can be treated with conservative intravesical instillation therapy, and which patient group will progress and might benefit from undergoing early cystectomy. Furthermore, first-line therapy, i.e. intravesical instillation of bacillus Calmette-Guérin (BCG), fails in more than 50 % of cases due to toxicity or treatment resistance, and second-line therapy radical cystectomy results in possible overtreatment and causes drastic lifestyle consequences. Therefore, in this proposal we aim to decipher the genetic landscape of urothelial CIS by performing a multiregional whole exome sequencing approach, initially on cryopreserved, completely embedded cystectomy specimens containing CIS. We will use bioinformatics to analyse clonal heterogeneity and evolution of CIS in order to understand the basic disease development and its dynamics, and to deduce prognostically relevant information for therapeutic stratification as well as to identify genetic events which hold promise for effective targeted therapy. Potentially druggable CIS alterations will be assessed functionally in in vitro models for their putative predictive and therapeutic impact. Based on the assumption that a more diverse tumour is able to adapt more efficiently to changing environmental conditions resulting in faster tumour growth and progression, we aim to determine the suitability of inter-patient within-CIS genetic diversity measures as a robust criterion for independent prognostic stratification (intravesical therapy versus radical cystectomy). Prospectively (in subsequent projects), we aim to validate the basic results from this project for CIS risk stratification in longitudinal biopsy cohorts, that we are currently establishing.