Figure EV1. Patient‐derived HGSC cells show variable cisplatin resistance in 3D collagen.

• A
  Confocal micrographs show PAX8 (green) in primary patient‐derived HGSC cells after 7‐days culture in 3D collagen. Cells were 62–87% positive for the nuclear HGSC marker. Scale bars: 20 μm.
• B, C
  Viability of patient‐derived HGSC cells cultured for 7 days in ascites‐like suspension or 3D collagen (B, C; viability of freshly isolated primary cells could only be assessed once with N = 3 experimental replicates) as well as in an adherent culture (C; N = 3) after 0–50 μM cisplatin treatment for 72 h. Cells derived from patient OCKI_p01, OCKI_p03, OCKI_p06, and OCKI_p13 showed treatment resistance particularly when embedded in 3D collagen.
• D, E
  Representative confocal micrographs show cytokeratin 7 (CK7, green), phalloidin (F‐actin, red), and cleaved caspase‐3 (clCasp3, orange) in 3D OCKI_p13 HGSC culture treated without or with 20 µM cisplatin for 72 h, 4 days after 3D embedding. Corresponding quantification for clCasp3 (E). Scale bars: 50 μm. N = 4.

Data information: In (B, C and E), data are presented as mean (SD). *P < 0.05. Exact P‐values are provided in Appendix Table S10, Student's t‐test.