TABLE 3.

HPV integration can occur during extended culturing

Clonea	32 PDs (t = 0 days)			∼120 PDs (t = 180 days)			Splice structureb	Gene locus
	HPV DNA status	PD time (days)	Karyotype	HPV DNA status	PD time (days)	Karyotype
A1	I	1.4	2N {46,XY}	I	1.4	2N {46,XY, add(3)(p26),i(8)(q10), +9}	880^h-chromosome 6	HMG AT Hook
A2	P	1.3	2N {46,XY}	I	1.4	2N {46,XY, i(8)(q10)}	880^3358
A3	I	1.7	2N {46,XY}	I	1.9	Near 4N {84∼89, XXY,-Y,-4,-7,i(8)(q10),del(11)(p11.2), −13,−14,−15,−16,+20}	880^h-chromosome 13	Unknown
A4	P	1.9	2N {46,XY}	I	1.9	2N {46,XY, i(8),(q10),+21}	880^unknown
A5	I	2.7	2N {46,XY}	I	1.3	>2N {52,XY, +5,+6,+9,+14,+20,+21}	880^h-chromosome 6	Laminin α2
A6	P	3.0	2N {46,XY}	P	1.5	2N {46,XY, add(5)(p13), add(6)(p25),add[15](q22)}	NDc

^aA set of six clonal HPV-16-immortalized human foreskin keratinocytes was cultured for 180 days, or an average of 120 population doublings (PDs), while monitoring the population doubling rate (PD) in days, viral DNA status (P, plasmid; I, integrated) by Southern blotting, and the host karyotype.

^bChimeric mRNAs were analyzed by 3′RACE and BLASTN v.2.2 comparison to human cellular sequences (GenBank). h-chromosome, human chromosome.

^cND, not determined.