The current standard preclinical oncology models are not able to fully recapitulate therapeutic targets and clinically relevant disease biology, evidenced by the 90% attrition rate of new therapies in clinical trials. Three-dimensional (3D) culture systems have the potential to enhance the relevance of preclinical models. However, the limitations of currently available cellular assays to accurately evaluate therapeutic efficacy in these models are hindering their widespread adoption. We assessed the compatibility of the lactate dehydrogenase (LDH) assay in 3D spheroid cultures against other commercially available readout methods. We developed a standardized protocol to apply the LDH assay to ex vivo cultures, considering the impact of culture growth dynamics. We show that accounting for growth rates and background release levels of LDH are sufficient to make the LDH assay a suitable methodology for longitudinal monitoring and endpoint assessment of therapeutic efficacy in both cell line-derived xenografts (xenospheres) and patient-derived explant cultures. This method has the added value of being non-destructive and not dependent on reagent penetration or manipulation of the parent material. The establishment of reliable readout methods for complex 3D culture systems will further the utility of these tumor models in preclinical and co-clinical drug development studies.

当前的标准临床前肿瘤学模型无法完全概括治疗靶点和临床相关疾病生物学，临床试验中新疗法的流失率为 90%，证明了这一点。三维 (3D) 培养系统有可能增强临床前模型的相关性。然而，目前可用的细胞检测在这些模型中准确评估治疗效果的局限性阻碍了它们的广泛采用。我们评估了 3D 球体培养物中乳酸脱氢酶 (LDH) 检测与其他市售读数方法的兼容性。考虑到培养生长动态的影响，我们开发了一个标准化的协议，将 LDH 检测应用于体外培养。我们表明，考虑到 LDH 的生长速率和背景释放水平，足以使 LDH 测定成为一种合适的方法，用于纵向监测和终点评估细胞系衍生的异种移植物（异种球）和患者衍生的外植体培养物的疗效。这种方法具有非破坏性的附加价值，并且不依赖于试剂渗透或对母体材料的操纵。为复杂的 3D 培养系统建立可靠的读出方法将进一步促进这些肿瘤模型在临床前和联合临床药物开发研究中的应用。这种方法具有非破坏性的附加价值，并且不依赖于试剂渗透或对母体材料的操纵。为复杂的 3D 培养系统建立可靠的读出方法将进一步促进这些肿瘤模型在临床前和联合临床药物开发研究中的应用。这种方法具有非破坏性的附加价值，并且不依赖于试剂渗透或对母体材料的操纵。为复杂的 3D 培养系统建立可靠的读出方法将进一步促进这些肿瘤模型在临床前和联合临床药物开发研究中的应用。