Apoptosis and its relationship with cell proliferation, p53, Waf1p21, bcl-2 and c-myc in esophageal carcinogenesis studied with a high-risk population in northern China

Table 1 Apoptosis and cell proliferation in esophageal epithelia with different severities of lesions

Histology	Apoptosis					PCNA immunostaining
	Number of samples examined	Percent of samples with apoptosis	Apoptotic indexa (mean ± SD)			Number of samples examined	Number of positive ells/mm2 (mean ± SD)
			AI	ACI	ABI
Normal	38	24	0.3 ± 0.7	0.2 ± 0.5	0.1 ± 0.4	31	200 ± 113
BCH	156	32	0.6 ± 0.9	0.3 ± 0.6b	0.2 ± 0.5	106	286 ± 150b
DYS	47	79c	1.8 ± 1.5b	0.9 ± 0.9b	0.8 ± 1.0b	31	719 ± 389b
SCC	38	100c	2.5 ± 2.1b	0.9 ± 0.9	1.6 ± 1.5b	26	1 261 ± 45b

^aACI, the number of apoptotic cells per mm²; ABI, the number of apoptotic bodies per mm²; AI, the number of both apoptotic cells and apoptotic bodies per mm².

^bStatistically different from the adjacent low-grade lesion by Wilcoxon rank-sum test,

^cP< 0.01.

Table 2 Changes of p53 and Waf1p21 in esophageal epithelia with different severities of lesions

Histology	p53 immunostaining		Waf1p21 immunostaining
	% of samples with positive stain % (n/N)a	Number of positive cells/mm2 (-x±s)	% of samples with positive stain % (n/N)a	Number of positive cells/mm2 (-x±s)
Normal	74 (23/31)	53 ± 7839	(11/28)	34 ± 72
BCH	87 (102/117)	74 ± 66	38 (14/37)	53 ± 10b
DYS	100 (31/31)	262 ± 341b	27 (3/11)	11 ± 20b
SCC	89 (23/26)	1 297 ± 1110b	14 (1/7)	8 ± 22

^an, positive cases; N, total cases examined.

^bStatistically different from the adjacent low-grade lesion by Wilcoxon rank-sum test, P < 0.01.

Table 3 Apoptotic indexes in samples with positive and negative immunoreactivity for p53, bcl-2 and c-myc in esophageal epithelia with different severities of lesions

Histology	p53 immunostaining				bcl-2 immunostaining				c-myc immunostaining
	Positive		Negative		Positive		Negative		Positive		Negative
	Na	AIb	N	AI	N	AI	N	AI	N	AI	N	AI
Normal	23	0.4 ± 0.8	8	0.2 ± 0.4	0	0	23	0.2 ± 0.6	4	0.6 ± 1.2	27	0.3 ± 0.6
BCH	102	0.4 ± 0.8	15	0.3 ± 0.6	5	0.1 ± 0.3	26	0.5 ± 1.1	15	0.8 ± 1.1	46	0.5 ± 1.1
DYS	31	1.8 ± 1.5	0		4	1.7 ± 1.3	6	1.9 ± 0.4	7	2.0 ± 1.7	6	0.7 ± 0.7
SCC	23	2.3 ± 2.1	3	1.1 ± 0.4	6	2.0 ± 0.9	1	2.8	16	2.2 ± 2.2	11	2.0 ± 1.8

^aN, Number of samples examined.

^bAI, apoptotic index, i.e., the number of apoptotic cells and apoptotic bodies per mm².