Deficiency of CCAAT/enhancer binding protein family DNA binding prevents malignant conversion of adenoma to carcinoma in NNK-induced lung carcinogenesis in the mouse

Table 1 Tumor multiplicities/incidences in NNK or saline-treated A-C/EBP- or A-C/EBP+ mice fed Dox or regular diet and analyzed at 52 weeks post-NNK/saline administration

Group	Genotype (*A-C/EBP*	Treatment	Diet	No. of mice	Body weight	Gross tumor		Histological	lesions		Tumor incidence
	+ or -^a)			examined	(g)	per mouse	Alveolar hyperplasia per mouse	Adenoma per mouse	Carcinoma per mouse	Adenoma and carcinoma per mouse	(%)^b
1	-	NNK	Dox	45	46.2±0.8^d,e	1.00	0.11^g	1.20^h	0.044	1.20^h	76 (34)^c
2	+	NNK	Dox	30	43.7±0.8^e	1.20	0.23	1.30^h	0.13	1.40^h	83 (25)
3	-	Saline	Dox	24	43.7±1.1	0.29	0.08	0.21	0	0.21	21 (5)
4	+	Saline	Dox	23	43.4±0.8^f	0.26	0.17	0.17	0	0.17	13 (3)
5	-	NNK	Regular	44	39.8±0.8	1.00	0.36	1.30^h	0	1.30^h	71 (31)ⁱ
6	+	NNK	Regular	40	38.4±0.9	1.00	0.30	1.50^h	0.025	1.60^h	88 (35)
7	-	Saline	Regular	38	40.8±1.2	0.27	0.18	0.32	0	0.32	26 (10)
8	+	Saline	Regular	31	39.9±0.9	0.26	0.19	0.26	0	0.26	19 (6)

^aA-C/EBP- is considered as wild-type control.
^bPercentage of mice with adenomas or carcinomas.
^cNumbers in parentheses show the number of mice having tumors.
^dSignificantly different from their respective A-C/EBP+ group (group 1 vs. 2) at P<0.05 by student t-test.
^eSignificantly different from their respective regular diet group (group 1 vs. 5, and 2 vs. 6) at P<0.00001 by student t-test.
^fSignificantly different from their respective regular diet group (group 4 vs. 8) at P<0.01 by student t-test.
^gSignificantly different from their respective regular diet group (group 1 vs. 5) at P<0.05 by student t-test.
^hSignificantly different from their respective saline group (group 1 vs. 3, 2 vs. 4, 5 vs. 7, and 6 vs. 8) at P<0.0001 by student t-test.
ⁱSignificantly different from their respective A-C/EBP+ group (group 5 vs. 6) at P=0.0497 by Fisher’s exact test.

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