Extended Data Fig. 9: Patterns of nuclear actin filaments in response to chemotherapy, RHOJ deletion and actin polymerization inhibitor.

a, Representative images of EPCAM⁻ cells transfected with HA-tagged RHOJ untreated and 12h after cisplatin/5FU treatment. Maximum intensity projections are shown (n = 3 biological replicates; anti-HA in red; nuclei are counterstained with DAPI in green; scale bar, 20μm) (top). Corresponding colocalization map of the overlap between HA-tagged RHOJ and DAPI signals showing peri- and intra- nuclear localization of RHOJ. Global intersection coefficient is represented (bottom). b, Representative images of the different nuclear actin patterns found in EPCAM⁺, EPCAM⁻ and EPCAM⁻ Rhoj KO cells expressing nuclear actin chromobody-GFP treated with cisplatin/5FU and a combination of cisplatin/5FU + Latrunculin B (LatB, 400nM) or SMIFH2 (50 µM) for 12h. Nuclei are counterstained with DAPI (blue) (n = 3; scale bar, 10μm). c, Quantification of nuclear actin patterns in EPCAM⁺, EPCAM⁻ and EPCAM⁻ Rhoj KO cells treated with cisplatin/5FU and a combination of cisplatin/5FU + Latrunculin B or SMIFH2 for 12h (Means are shown, n represents the number of independent primary cultured cell lines). Several classes of nuclear actin filaments are observed (b). Pattern 1, thin, short and branched filaments, is found in all cell types as shown in panel highlighted by a purple border ; pattern 2, elongated filaments, is mainly induced in EPCAM⁻ cells upon chemotherapy treatment as shown in panel highlighted by an orange border; pattern 3, hairy filaments which are short filaments with a dense and multipolar organization, is detected in EPCAM⁻ Rhoj KO cells, as shown in panel highlighted by a blue border; pattern 4, thick and twisted actin filaments as shown in panel highlighted by a yellow border and pattern 5, severe disruption of actin filaments as shown in panel highlighted by a green border, are found when chemotherapy was combined with F-actin inhibitors.