PO.BCS01.03 · 生物信息与计算
利用可解释的深度学习框架为精准肿瘤学解锁新型基因生物标志物
Unlocking novel gene-based biomarkers using an explainable deep learning framework for precision oncology
作者与单位 Authors & Affiliations
摘要 Abstract
中文摘要
体细胞基因组改变在癌症中被广泛分析,并仍是个性化治疗的主要指标,然而其临床效用仅限于一小部分可操作靶点,仅使一小部分患者受益。AI/ML通过利用大规模基因组数据,为精准肿瘤学提供了一条变革性路径,但其较差的可解释性(往往简化为单基因见解)限制了临床应用,并忽视了癌症的生物学复杂性。我们通过一个结合PhenoMap和PhenoSurv的新型框架来弥补这一空白。PhenoMap使用超过9,000个泛癌基因组和转录组,采用LASSO-随机森林相结合的方法,经训练以模拟MSigDB中6,000多条通路的富集分数,将基因水平的改变转换为表型特征图谱。该图谱作为PhenoSurv的输入,PhenoSurv是一种旨在预测无病生存期的变分自编码器。PhenoSurv采用创新架构,可清晰地嵌入十一种表型,并在潜在空间上优化重建损失、Kullback-Leibler散度和Cox生存损失。这产生了与生存相关的潜在特征,能够发现多表型脆弱性和预后生物标志物,我们在乳腺癌、肺癌和脑癌中对此进行了测试和验证。在内部和外部验证中超过基线表现的PhenoMap通路,肺癌有3,382条,脑癌有3,772条,乳腺癌有4,188条。按PhenoMap分数聚类揭示了具有共享主导信号通路的患者亚群。值得注意的是,PI3K和KRAS信号富集的聚类中,分别包含了在乳腺癌中缺乏PIK3CA突变(54%)或在肺癌中缺乏KRAS突变(67%)的患者,表明PhenoMap识别出了超越单基因生物标志物、适合靶向治疗的更广泛人群。PhenoSurv在各癌症类型的生存预测中优于现有的AI/ML模型,同时在表型、通路和基因层面提供多层次的可解释性。使用DeepSHAP,我们识别出了在各队列中驱动预测的关键通路。超过50个通路级生物标志物在高信号组和低信号组之间显示出显著的生存差异,包括乳腺癌中的NOTCH1信号(TCGA:p = 0.0098;MSK:p = 0.003)、肺癌中的CLEC7A炎症小体通路(TCGA:p = 0.0045;MSK:p = 0.041)以及脑癌中的肌醇磷酸代谢(两者均p < 0.0001)。在各癌症类型中,生存率随不良预后标志物数量的增加而逐步下降。PhenoMap和PhenoSurv通过提供基于临床基因组数据、能揭示临床可操作生物标志物的可解释模型,弥合了精准肿瘤学中的一个关键空白。这些基于机制的见解能够实现生物学上有依据的患者分层,为更有效的个性化治疗策略铺平道路。
查看英文原文 English abstract
Somatic genomic alterations are widely profiled in cancer and remain the primary indicator for personalized therapy, yet their clinical utility is limited to a small set of actionable targets benefiting only a fraction of patients. AI/ML offers a transformative path to precision oncology by leveraging large-scale genomic data, but poor interpretability, often reduced to single-gene insights, limits clinical adoption and overlooks cancer's biological complexity. We address this gap with a novel framework combining PhenoMap and PhenoSurv. PhenoMap converts gene-level alterations into a phenotypic feature map using over 9,000 pan-cancer genomes and transcriptomes, trained to emulate enrichment scores for 6,000+ pathways from MSigDB using a combined LASSO-Random Forest approach. This map serves as input to PhenoSurv, a variational autoencoder designed to predict disease-free survival. PhenoSurv employs an innovative architecture that distinctly embeds eleven phenotypes and optimizes reconstruction loss, Kullback-Leibler divergence, and Cox survival loss on the latent space. This yields survival-relevant latent features, enabling discovery of multi-phenotypic vulnerabilities and prognostic biomarkers, which we tested and validated in breast, lung, and brain cancer. PhenoMap pathways that exceeded baseline performance in internal and external validation included 3,382 for lung, 3,772 for brain, and 4,188 for breast cancer. Clustering by PhenoMap scores revealed patient subsets with shared dominant signaling pathways. Notably, PI3K and KRAS signaling-enriched clusters included patients lacking PIK3CA (54%) or KRAS (67%) mutations in breast and lung cancer, respectively, indicating PhenoMap identifies broader cohorts for targeted therapy beyond single-gene biomarkers. PhenoSurv outperformed existing AI/ML models for survival prediction across cancer types while providing multilevel explainability at phenotype, pathway, and gene levels. Using DeepSHAP, we identified key pathways driving predictions across cohorts. Over 50 pathway-level biomarkers showed significant survival differences between high- and low-signaling groups, including NOTCH1 signaling in breast cancer (TCGA: p = 0.0098; MSK: p = 0.003), the CLEC7A inflammasome pathway in lung (TCGA: p = 0.0045; MSK: p = 0.041), and inositol phosphate metabolism in brain cancer (both p < 0.0001). Survival declined progressively with the number of poor prognostic markers across cancer types. PhenoMap and PhenoSurv bridge a critical gap in precision oncology by delivering interpretable models based on clinical genomic data that reveal clinically actionable biomarkers. These mechanism-based insights enable biologically informed patient stratification, paving the way for more effective personalized treatment strategies.
利益披露 Disclosure
S. Grant, None..
A. Nath, None.