Table 1.

Characteristics of the four PCA clusters(p1-p4)

Fisher's exact test	p1		p2		p3		p4
	Data set 1 (n = 4)	Data set 2 (n = 10)	Data set 1 (n = 4)	Data set 2 (n = 10)	Data set 1 (n = 6)	Data set 2 (n = 5)	Data set 1 (n = 3)	Data set 2 (n = 5)
High stage (3 or 4)	0,053*	0,056	0,330	0,691	0,075	0,355	0,324	1,000
Stage 4	0,029*	0,001**	0,241	0,062	0,088	0,304	0,124	0,696
Outcome	0,139	0,051*	0,555	1,000	0,072	1,000	0,728	0,070
MNA	0,208	0,375	0,208	0,141	0,001**	0,003**	0,324	1,000
Del1p	0,088	0,210	0,088	0,067	0,018*	3,9E-04**	0,360	0,589
Del11q	0,441	0,235	0,559	0,013*	0,160	0,622	0,051*	0,622
Gain17q	0,063	0,128	0,365	0,109	0,058	1,000	0,458	0,651
ANOVA one-way	ANOVA significance		FC p1		FC p2		FC p3		FC p4
	Data set 1	Data set 2	Data set: 1	2	Data set: 1	2	Data set: 1	2	Data set: 1	2
ALK	1,1E-03**	0,277	-1,8	-0,5	1,2	0,0	3,6	1,4	-1,0	-0,6
BIRC5	6,1E-06**	1,4E-05**	-2,9	-1,7	2,9	2,0	7,8	2,1	-3,0	-2,6
CCND1	0,011*	0,003**	0,5	1,1	2,0	0,4	1,0	0,1	-1,9	-2,6
MYCN	2,0E-04**	7,0E-04**	-0,6	-0,3	0,4	-0,4	12,6	2,4	-3,5	-1,4
NTRK1	6,7E-04**	1,1E-05**	3,7	3,4	3,6	0,7	0,1	-4,0	-0,3	-2,6
PHOX2B	0,006**	3,4E-08**	0,5	0,6	2,0	1,0	1,2	0,7	-2,3	-3,2

Fisher's exact test: Each cluster (p1, p2, p3, or p4) versus the other clusters combined. n = the number of samples in each subgroup. High stage = INSS stage 3 and 4; outcome = dead of disease; MNA = MYCN amplification; del = deletion. Significance is marked by stars: * p < 0.05, ** p < 0.01. ANOVA one-way: The differential expressions from six genes in PCA clusters (p1-p4) were tested by an ANOVA one-way test. Significance is marked by stars: * p < 0.05, ** p < 0.01. FC = The log2 fold change of genes in each PCA group compared to the other groups combined.