Identification of human papillomavirus DNA gene sequences in human breast cancer

Abstract

Human papilloma viruses (HPVs) are accepted as being carcinogenic in human cervical and anogenital cancers. The suspicion that HPVs may also have a role in human breast cancer is based on the identification of HPVs in human breast tumours and the immortalisation of normal human breast cells by HPV types 16 and 18. For this investigation, DNA that had been previously extracted and fresh frozen at À701C from 50 unselected invasive ductal breast cancer specimens were screened by polymerase chain reaction (PCR) for HPV type 16, 18 and 33 gene sequences. We show that HPV 18 gene sequences are present in DNA extracted from breast tumours in Australian women. Overall, 24 (48%) of the 50 samples were HPV positive. Overall no correlations with tumour grade, patient survival, steroid receptor status, ERB-2, p53 expression and mutation were observed. Human papilloma viruses may have a role in human breast cancer. We speculate that HPVs may be transmitted by hand from the female perineum to the breast. It is accepted that human papillomavirus (HPV) types 16 and 18 are carcinogenic, and that probably HPV types 31 and 33 are also carcinogenic in human cervical and anogenital cancers (IARC, 1995). The suspicion that HPVs may also have a role in human breast cancer is based on the identification of HPVs in human breast tumours and the immortalisation of normal human breast cells by HPV 16 and 18 (Band et al, 1990;De Villiers et al, 2005).Human papilloma virus 16 has been identified in breast tumours in Italian women and breast tumours in Norwegian women who had previous cervical neoplasia (Hennig et al, 1999). Human papilloma virus 33 has been identified in breast cancer in Chinese and Japanese women (Yu et al, 1999) MATERIALS AND METHODSFor this investigation, DNA that had been previously extracted and fresh frozen at À70 O C from 50 unselected invasive ductal breast cancer specimens were screened by polymerase chain reaction (PCR) for HPV type 16, 18 and 33 gene sequences. The DNA samples were amplified twice per sample using GenomiPhit DNA Amplification Kit (Amersham Biosciences). The DNA quality was confirmed by PCR, amplifying 268 bp of the b-globin gene. These samples were then screened for the presence of HPV by PCR using primers that could detect 140 bp in the E6 region of HPV 16, 18 and 33 (Yu et al, 1999). DNA extracted from cervical cancer cell lines HeLa and SiHa cells were used as positive controls for HPV 18 and 16, respectively. Plasmid plink 322 HPV 33 was used as a positive control for HPV 33. DNA from leukaemia Raji cells was used a negative control. The PCR products were separated on 7.6% PAGE and visualised by SYBR Green I (Molecular Probes). The screening was repeated five times using different batches of DNA samples amplified by the GenomiPhit DNA Amplification Kit (Amersham Biosciences). Human papilloma virus-positive samples were sequenced (there was sufficient material to sequence 18 of 24 HPV-positive samples).Grade of tumour and survival of patients were known for each sample. Screening for exons 5...

Analysis of the presence of cutaneous and mucosal papillomavirus types in ductal lavage fluid, milk and colostrum to evaluate its role in breast carcinogenesis

“…Different hypotheses can be envisaged to explain these findings. It is possible that the most frequently detected HPV types in the DL fluids (9,22,23 and 38) are present on the skin of the nipple at a higher copy number than the other beta HPVs. Therefore, they have a higher probability than the others to be transported by the catheter into or infect the ducts.…”

“…Low or high prevalence of HPV DNA in breast cancer of women was found in several studies. HPV16 or HPV18 were preferentially found in European women, while other types, e.g., 33, were frequently found in Japanese and Chinese cohorts [6][7][8][9][10][11][12][13][14][15][16]. De Villiers et al have recently shown that a broad spectrum of mucosal and cutaneous HPV types could be found in breast specimens using several PCR-based methods [16].…”

Are some breast cancers sexually transmitted?

“…There were no differences in the average of age of women with either HPV-positive and -negative breast cancer in a study of Brazilian women (Damin et al, 2004). This is in contrast to a recent study of Greek women in which those with HPV-positive breast cancer were of average age 38 years as compared to average age 53 years for women with HPV-negative breast cancer (P-values for difference ¼ 0.001) (Kroupis et al, 2006).We have reviewed the ages of Australian women with HPVpositive and -negative breast cancer in our study published in this Journal (Kan et al, 2005). These data are shown in Table 1.…”

“…High-risk HPVs of the same type have been identified in both cervical and breast cancer that had occurred in the same women (Hennig et al, 1999;Widschwendter et al, 2004). This observation has lead to the hypothesis that HPVs may be transmitted to the breast during sexual activities (Kan et al, 2005). If this hypothesis is correct, it is likely that HPV-positive breast cancers would occur in women younger than those with HPV-negative breast cancer.…”

“…We have reviewed the ages of Australian women with HPVpositive and -negative breast cancer in our study published in this Journal (Kan et al, 2005). These data are shown in Table 1.…”