Human papillomavirus (HPV) integration signature in cervical lesions: identification of MACROD2 gene as HPV hot spot integration site.

BACKGROUND

High-risk HPV is clearly associated with cervical cancer. Integration of HPV DNA into the host genome is considered a key event in driving cervical carcinogenesis. However, the mechanism on how HR-HPV integration influences the host genome structure has remained enigmatic.

METHODS

In our study, 25 DNA samples including 11 from fresh-frozen cervical carcinomas and 14 from fresh-frozen high-grade squamous intraepithelial lesion (HSILs) were detected using the method of HPV capture combined with next generation sequencing.

RESULTS

We calculated the frequency in each viral gene or region and found that breakpoints were prone to occur in L1 and L2 instead of E2 in the cervical cancer (P = 0.0004 and P = 5.15 × 10-40) and HSIL group (P = 2.1 × 10-32 and P = 7.06 × 10-13). The results revealed that HPV16 showed a strong tendency toward intronic region (P = 5.02 × 10-64) but a subtle tendency toward intergenic region (P = 0.04). The most frequent integration site was in the MACROD2 gene (introns 2, 4, 5, 6, 8 and 9), which in MACROD2 functional domain.

CONCLUSION

Our results revealed that MACROD2 is HPV hot spot integration site in cervical lesions, and its deficiency alter DNA repair and sensitivity to DNA damage thought impaired PARP1 activity resulting in chromosome instability.