DNA of mouse mammary tumor virus‐like virus is present in human tumors influenced by hormones

Abstract

Mouse mammary tumor virus (MMTV) is a hormonally regulated, oncogenic virus of mice. MMTV-like virus DNA has previously been detected in human breast cancers, liver disease, and liver cancers. It is hypothesized that local hormonal effects might be of primary importance in determining MMTV-like virus detection in human tumors. MMTV-like virus envelope (env) DNA was determined using nested PCR in 89 ovarian, 147 prostate, 50 endometrial, 141 skin, and 51 lung cancers. Viral-positive sequences were compared with published MMTV-like viral sequences from human breast cancer, liver cancer and MMTV. Immunohistochemistry for estrogen receptor (ER-alpha) and progesterone receptor (PgR) was performed on a subset of tumors. MMTV-like virus env DNA was detected in ovarian cancers (14/89; 16%), prostate cancers (53/147; 36%), endometrial cancers (5/50; 10%), skin cancers (13/141; 9%) but not in lung cancers (0/51). Phylogenetic analysis of the viral-positive sequences showed no clustering of the isolates according to tissue type. A significant association was observed between the presence of hormone receptors and detection of MMTV-like virus in the human cancers screened (P = 0.01). A significant association between MMTV-like virus and PgR was noted in skin cancers (P = 0.003). Therefore, unlike the mouse model, the detection of MMTV-like env sequences in human cancers in addition to breast indicates that MMTV-like viral expression is not breast cancer-specific and may relate to hormone-dependent viral expression.

Epstein-Barr Virus, Human Papillomavirus and Mouse Mammary Tumour Virus as Multiple Viruses in Breast Cancer

“…EBV has been associated with Hodgkins lymphoma, Burkitts lymphoma and nasopharyngeal cancer. MMTV has been identified in human breast, prostate and liver tissues [20], [41].…”

Mouse mammary tumor virus-like gene sequences are present in lung patient specimens

“…It could be the explanation of the different between them [15,24]. Previous studies report on the presence of viruses in patients who have other malignancies [25]. In a previous paper, we reported on the presence of MMTV-like gene sequences in the INER51 lung cancer cell line.…”

“…We amplified the MMTV-like LTR-gag region using the primers reported by Liu et al to confirmed their positivity [18] Furthermore, we used the INER51 cell line as a positive control. In 2010, Johal H et al[25] reported on the detection of MMTV-like env sequences in ovarian, prostate, endometrial, and skin cancers, but not in lung cancer, indicating that MMTV-like presence is not restricted to breast cancer cells. We detected MMTV-like gene env sequences in the INER51 lung cancer cell line [23].…”

Human Mammary Tumor Virus (HMTV) in Endometrial Carcinoma

“…While this work was in progress, a report was published indicating that MMTV-like sequences were present in 10% of the ECs of Australian women. 11 In this communication, we show that 23.2% of the ECs tested in American women contained HMTV env gene sequences, which are 94% homologous to MMTV. We exclude the possibility of contamination with mouse sequences by careful testing for the presence of murine DNA in all experiments.…”