Fig. 8: The ATM/ATR-KIFC1-centrosome clustering pathway promotes tumor recurrence.

a Schematic drawing of tumor recurrence, as described in the Methods section. Xenograft tumors were treated with etoposide alone and in combination with PBS, VE-822, or CW069, and were allowed to grow up to a mean volume of 300 mm³ before being surgically resected. After surgery, the mice were treated with the indicated drugs for another 2 weeks. After 5 months with no drug treatment, mice with tumor recurrence were identified and analyzed. b The time at which the indicated tumors reached 300 mm³. Data represent mean ± SD (n = 10). Two-tailed t test p values (from left to right): p = <0.00001 and <0.00001. c, d KIFC1-S26 phosphorylation promotes CIN in xenograft tumors. The indicated cells were isolated from the surgically resected tumors and then were cultured to assess the rate of CIN in vitro. For each experimental condition, 100–150 cells were counted, and three independent experiments were performed. c The graph shows the fraction of indicated cells with different numbers of chromosomes per cell. For each experimental condition, 100–127 cells were counted, and three independent experiments were performed. Two-tailed t test p values (from left to right): p = 0.0022, 0.0035, 0.0021, and 0.0008. d The graph shows the fraction of the indicated cells stained for centromeric DNA on chromosomes 3 and 7 with FISH analysis. For each experimental condition, 100-124 cells were counted, and three independent experiments were performed. Two-tailed t test p values (from left to right): p = 0.0092 and 0.0077. e Graph depicting the Kaplan-Meier analysis of tumor recurrence in the different groups. Survival cutoff criteria (compassionate euthanasia), when the recurrent tumors impeded ambulation, defecation, urination, or eating. Each group, n = 10. Two-tailed t test p values (from left to right): p = 0.0442 and 0.0291. f Representative images showing local recurrence and distant recurrence (lung metastases). The boxed enlargements showed tumor morphology. Hematoxylin and eosin staining of tumor tissue sections. g, h KIFC1-S26 phosphorylation promotes CIN in the locally recurrent tumors. Recurrence-WT (Rec-WT) and recurrence-S26D (Rec-S26D) cells were isolated from the indicated recurrent tumors and then were re-cultured to assess the rate of CIN in vitro. The untreated cells were MDA-MB-231 cells. Data represent the mean ± SD of three times of independent experiments. For each experimental condition, 100–109 cells were counted, and three independent experiments were carried out. g The graph shows the fraction of indicated cells with different numbers of chromosomes per cell. For each experimental condition, 100–109 cells were counted, and three independent experiments were performed. Two-tailed t test p values (from left to right): p = 0.0022, 0.0031, 0.0079, and 0.0024. h The graph showed the fraction of the indicated cells stained for centromeric DNA on chromosomes 3 and 7 with FISH analysis. For each experimental condition, 100–159 cells were counted, and three independent experiments were performed. Two-tailed t test p values (from left to right): p = 0.0261, 0.0098,0.0047, and 0.0164. *p < 0.05; **p < 0.01. Source data are provided as a Source Data file.