Radiation response assessment of organoids derived from patients with pancreatic cancer

Abstract

Background: The effectiveness of radiotherapy for pancreatic cancer is debated. Patient-derived organoids (PDOs) already mimicked clinical radiation response in other cancer types, which could be valuable in pancreatic cancer as well. This study aimed to investigate whether PDOs can be used to model RT response in pancreatic cancer and to explore the presence of a dose-response correlation.

Methods: PDOs derived from two pancreatic cancer patients (HUB-08-B2-022A and HUB-08-B2-026B) were irradiated with doses ranging from 0 to 40 Gray. Viability assessments were conducted after seven and 10 days by measuring ATP-levels. Results were normalized, defining the viability at 0 Gray as 100 % and an absolute viability of 0 as 0 %. The relative area under the curve (rAUC) was calculated (0 = total sensitivity, 1 = total resistance).

Results: With a readout time of seven days, both HUB-08-B2-022A and HUB-08-B2-026B exhibited viability above 50 % at the highest dose of 12 Gy (rAUC of 0.79 and 0.69, respectively). With a readout time of 10 days, both PDOs showed a dose-response relation although HUB-08-B2-022A was more sensitive than HUB-08-B2-026B (rAUC of 0.37 and 0.51, respectively). Increasing the radiation dose to 40 Gy did not further affect viability, but the dose-response relation remained present (rAUC of 0.13 and 0.26, respectively). In the final experiment with a readout time of 10 days and a maximum dose of 14 Gy, the dose-response correlation was paramount in both PDOs (rAUC 0.28 and 0.45, respectively), with HUB-08-B2-022A being most sensitive.

Conclusions: In this setup, both pancreatic cancer PDOs showed an irradiation dose-response correlation. These preliminary findings suggest that pancreatic cancer PDOs are suitable for assessing radiation response in vitro. Further experiments are needed to eventually simulate treatment responses to personalized treatment strategies.

Keywords: Dose–response correlation; Pancreatic ductal adenocarcinoma; Patient derived organoids; Radiation; Radiotherapy; Response; Sensitivity.

Fig. 1

Experimental set-up of in vitro drug screens on Patient Derived Organoids (PDOs) derived from pancreatic cancer. PDOs were derived from pancreatic cancer tissue derived from patients during their resection. They were cultured in Matrigel, immersed in organoid culture medium. Three days prior to the drug screens, the PDOs were enzymatically made single cell. On the day of the experiment, they were plated on 96-well plates after which they were irradiated with doses ranging from 0–40 Gray, depending on the set-up. Seven to 10 days later, viability was assessed. D day(s); H hours.

Fig. 2

First radiation response assessment (0–12 Gray with seven days incubation time). a: Graph shows ATP viability assays (%) at seven days after receiving irradiation doses ranging from 0–12 Gray b: Cell imaging of HUB-08-B2-022A at seven days after receiving doses ranging from 0–12 Gray, c: Cell imaging of HUB-08-B2-026B at seven days after receiving doses ranging from 0–12 Gray.

Fig. 3

Second radiation response assessment (0–12 Gray with 10 days incubation time). a: Graph shows ATP viability assays (%) at 10 days after receiving irradiation doses ranging from 0–12 Gray b: Cell imaging of HUB-08-B2-022A at 10 days after receiving doses ranging from 0–12 Gray, c: Cell imaging of HUB-08-B2-026B at 10 days after receiving doses ranging from 0–12 Gray.

Fig. 4

Third radiation response assessment (0–40 Gray with 10 days incubation time). a: Graph shows ATP viability assays (%) at 10 days after receiving irradiation doses ranging from 0–40 Gray b: Cell imaging of HUB-08-B2-022A at 10 days after receiving doses ranging from 0–40 Gray, c: Cell imaging of HUB-08-B2-026B at 10 days after receiving doses ranging from 0–40 Gray.

Fig. 5

Final radiation response assessment (0–14 Gray with 10 days incubation time). a: Graph shows ATP viability assays (%) at 10 days after receiving irradiation doses ranging from 0–14 Gray b: Cell imaging of HUB-08-B2-022A at 10 days after receiving doses ranging from 0–14 Gray, c: Cell imaging of HUB-08-B2-026B at 10 days after receiving doses ranging from 0–14 Gray.