Specific intronic p53 mutation in esophageal squamous cell carcinoma in Southern Thailand

Table 1 Summary of patient characteristics

Variable	Category	No. of subjects	Frequency (%)
Sex	Male	139	84.2
	Female	26	15.8
Age (yr)	Mean, range	63.4 (37-91)
Smoking	Never	19	11.6
	Habitual	143	86.7
	Occasional	3	1.8
Drinking	Never	33	20.0
	Habitual	120	72.7
	Occasional	12	7.3
Betel chewing	Never	78	48.1
	Habitual	62	38.3
	Occasional	22	13.6

Table 2 Location and type of mutations

Location	n (%)
Exon 5	11 (25.58)
Exon 6	1 (2.33)
Exon 7	9 (20.93)
Exon 8	11 (25.58)
Intron 5	1 (2.33)
Intron 6	8 (18.60)
Intron 8	1 (2.33)
Exon-intron 6	1 (2.33)
Type of mutations
Transitions
G:C -> A:T	8 (18.60)
G:C -> A:T at CpG	4 (9.30)
A:T -> G:C	2 (4.65)
Transversions
G:C -> C:G	13 (30.23)
G:C -> T:A	7 (16.28)
A:T -> T:A	4 (9.30)
Tandem
GT -> TA	1 (2.33)
Deletion	4 (9.30)

Table 3 p53 mutations in esophageal squamous cell carcinoma patients from Songkhla, Southern Thailand

Case ID	Age (yr)/sex	Exon	Codon	Nucleotide change	AA change	Exposure
						Smoke	Alcohol	Betel
E111	60/M	5	130-131	3 bp deletion	Frameshift	Yes	Yes	Yes
E303	73/M	5	134-137	10 bp deletion	Frameshift	-	-	-
E006	63/M	5	156	CGC -> CCC	Arg -> Pro	Yes	Yes	No
E271	57/M	5	158	CGC -> CTC	Arg -> Leu	Yes	Yes	No
E072	58/F	5	159	GCC -> CCC	Ala -> Pro	Yes	Yes	Yes
E200	60/F	5	161	GCC -> ACC	Ala -> Thr	Yes	Yes	Yes
E397	56/M	5	167	CAG -> CGG	Gln -> Arg	Yes	Yes	No
E379	66/M	5	168	CAC -> CTC	His -> Leu	Yes	Yes	No
E355	61/M	5	176	TGC -> TTC	Cys -> Phe	Yes	No	Yes
E014	77/M	5	176	TGC -> TAC	Cys -> Tyr	No	Yes	Yes
E022	46/M	5	184	GAT -> AAT	Asp -> Asn	Yes	Yes	Yes
E464	68/M	6	190	CCT -> CTT	Pro -> Leu	Yes	Yes	No
E259	60/M	7	228-232	21 bp deletion	Frameshift	Yes	Yes	No
E320	72/M	7	234	TAC -> TGC	Tyr -> Cys	No	Yes	Yes
E264	52/M	7	238	TGT -> TAT	Cys -> Tyr	Yes	Yes	No
E446	58/M	7	245	GGC -> CGC	Gly -> Arg	Yes	Yes	No
E106	56/M	7	248	CGG -> CAG (CpG site)	Arg -> Gln	Yes	Yes	No
E298	79/F	7	248	CGG -> TGG (CpG site)	Arg -> Trp	Yes	No	Yes
E294	52/M	7	248	CGG -> TGG (CpG site)	Arg -> Trp	Yes	Yes	No
E419	54/M	7	248	CGG -> TGG (CpG site)	Arg -> Trp	Yes	Yes	No
E022	53/M	7	249	AGG -> ATG	Arg -> Met	Yes	Yes	No
E012	74/M	8	266	GGA -> TGA	Gly -> Ter (end)	Yes	Yes	No
E231	54/M	8	272	GTG -> TAG	Val -> Ter (end)	Yes	Yes	Yes
E455	46/M	8	272	GTG -> ATG	Val -> Met	No	Yes	Yes
E449	47/M	8	278	CCT -> TCT	Pro -> Ser	No	Yes	Yes
E002	53/M	8	279	GGG -> GAG	Gly -> Glu	Yes	Yes	-
E027	54/M	8	280	AGA -> AGT	Arg -> Ser	Yes	Yes	No
E444	79/M	8	283	CGC -> CCC	Arg -> Pro	No	Yes	No
E387	74/F	8	286	GAA -> CAA	Glu -> Gln	Yes	Yes	No
E146	62/M	8	287	GAG -> TAG	Glu -> Ter (end)	Yes	Yes	No
E181	58/F	8	287	GAG -> TAG	Glu -> Ter (end)	No	No	No
E408	58/F	8	296	CAC -> CTC	His -> Leu	No	No	No
E462	74/M	Exon-intron 6		21 bp deletion	Affect splice site	Yes	Yes	No
E023	51/F	Intron 5		TGAGC -> TCTGC	-	No	No	Yes
E158	61/M	Intron 6		GGGG -> GGCG	-	Yes	Yes	Occ
E169	53/M	Intron 6		GGGG -> GGCG	-	Yes	Yes	No
E189	60/M	Intron 6		GGGG -> GGCG	-	Yes	Yes	Yes
E199	48/M	Intron 6		GGGG -> GGCG	-	Yes	Yes	Yes
E240	61/M	Intron 6		GGGG -> GGCG	-	Yes	Yes	-
E302	41/M	Intron 6		GGGG -> GGCG	-	Yes	Yes	Occ
E329	63/M	Intron 6		GGGG -> GGCG	-	Yes	Yes	Yes
E435	45/M	Intron 6		GGGG -> GGCG	-	Yes	Yes	No
E409	56/M	Intron 8		ACGAG -> ACTAG	-	Yes	Yes	Yes

Occ: Occasional.

Table 4 Mutation frequency in relation to clinical factors and exposure n (%)

Variables	Mutant p53	Wild-type p53	P value
Sex
Male	36 (25.9)	103 (74.1)
Female	6 (23.1)	20 (76.9)	0.762
Age (yr)
≤ 60	24 (38.7)	38 (61.3)
> 60	18 (17.5)	85 (82.5)	0.002
Family history
Yes	6 (37.5)	10 (62.5)
No	33 (23.7)	106 (76.3)	0.230
Smoking
Yes	34 (23.8)	109 (76.2)
No/occasional	8 (36.4)	14 (63.6)	0.207
Drinking
Yes	27 (22.5)	93 (77.5)
No/occasional	15 (33.3)	30 (66.7)	0.155
Betel chewing
Yes	15 (24.2)	47 (75.8)
No/occasional	25 (25.0)	75 (75.0)	0.908