Abstract 5268: Drug screening of non-small cell lung cancer patient-derived organoids in a microwell platform
Authors: Luan Qiyue , Pulido Ines , Zhou Jian , Shimamura Takeshi , Papautsky Ian 
Published: April 2023

Patient-derived organoids (PDOs) have been widely accepted as ideal 3D tumor models for drug response prediction. However, research involving non-small cell lung cancer (NSCLC) PDOs is hampered by the compromised sample size and the lack of appropriate platforms tailored for scarce samples. Although BME2 domes show promising results in PDO maintenance and drug testing, the need for relatively large sample and the long incubation time hinder their application in drug response studies. Here, we report an agarose microwell (AMW) platform requiring miniscule sample volume for PDO rapid drug screening.

The AMWs were formed by 3D-printed molds and attached to the bottom of 24-well plates. Each well has ~400 agarose microwells with 200μm diameter, 75μm depth and U-shaped bottom. Seeded cells migrate and form spheroids in each microwell. NSCLC spheroids of H358 (KRASG12C), A549 (KRASG12S) and PDOs CK7152 (KRASG12C, obtained from NCI PDMR) were cultured in arrays and treated by KRASG12C inhibitor adagrasib.

PDOs normally grow in a BME2 dome, however large PDO size variability and consumption complicate drug evaluation. The AMWs are biocompatible and have a smooth surface that allows single cells or PDOs to migrate into microwells within 1d. The amount of PDOs in one dome is enough for 4 wells of 24-well plate. After 7d culture, PDOs formed in AMW exhibited high viability (89%±7% in AMW vs. 89%±11%, in dome) and better size uniformity (CV 29% in AMW vs. 44% in dome).

AMWs can easily be implemented to standardize cytotoxicity evaluation. Following the exposure to adagrasib for 72h, we found that H358 spheroids were sensitive to KRASG12C specific inhibitor adagrasib in dose-dependent manner with an IC50 of 88nM; whereas A549 spheroids -without the target mutation- was not responsive. CK7152 PDOs were also exquisitely sensitive to adagrasib (34% and 21% viability reductions viability in AMWs and dome).

Drug sensitivity can be affected by several factors that maintain proliferative signals active in tumor microenvironment. We have been able to simulate the effect of the tumor microenvironment, by culturing spheroids and PDOs with fibroblast supernatant in AMWs. The IC50 of adagrasib for H358 spheroids treated with WI-38 supernatant was about 3.5 × higher than that in normal medium (310nM vs. 88nM). We replicated these results with CK7152 PDOs treated with CAF supernatant that significantly decreased viability from 24% to 51% (p&lt;0.001) following 72h treatment of 500nM adagrasib.

Our AMW is a convenient 3D culture platform that generates uniform spheroids from a small sample volume for highly consistent drug screening results. The adagrasib drug response observed in AMW was comparable to that in conventional dome culture. Resistance due to tumor microenvironment can be readily assessed using fibroblast supernatant in AMW platform, promising for pre-clinical drug screening and personalized medicine.

Citation Format: Qiyue Luan, Ines Pulido, Jian Zhou, Takeshi Shimamura, Ian Papautsky. Drug screening of non-small cell lung cancer patient-derived organoids in a microwell platform. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5268.