Detection of human papillomavirus DNA in feline premalignant and invasive squamous cell carcinoma

Abstract

Squamous cell carcinoma (SCC) is the most common malignant cutaneous and oral neoplasm of cats. Papillomavirus (PV) DNA has been identified in a proportion of feline Bowenoid in situ carcinomas (BISCs), cutaneous SCCs and a single oral SCC, but its exact role in the pathogenesis remains unknown. In humans, it has been suggested that ultraviolet (UV) light and human PV (HPV) may act as cofactors in cutaneous SCC carcinogenesis. Little is known about the influence of UV light on PV prevalence in feline cutaneous lesions, including actinic keratosis (AK). Additionally, PV prevalence in noncutaneous feline lesions, including oral SCC, is largely not known. This study aimed to determine the presence of PV in 84 cats with premalignant and invasive SCC from cutaneous and noncutaneous sites using polymerase chain reaction and to investigate an association with UV light. Papillomaviral DNA was amplified from two of 12 cases of AK, seven of 22 BISCs, nine of 39 cutaneous SCCs and two of 35 non-cutaneous SCCs. Of the PV DNA sequenced, 50% was most similar to HPV of the genus Betapapillomavirus, while the other 50% was most similar to Felis domesticus PV type 2. Exposure to UV was not associated with an increase in PV for cutaneous SCC. The results of this study suggest that in the cat, HPV DNA may be detectible within a higher percentage of squamous lesions than previously demonstrated, UV exposure may not be a confounder for PV presence, and noncutaneous lesions may have a low prevalence of PV.

Loss of Retinoblastoma Protein, But Not p53, Is Associated With the Presence of Papillomaviral DNA in Feline Viral Plaques, Bowenoid In Situ Carcinomas, and Squamous Cell Carcinomas

“…Of the 26 lesions that demonstrated reduced pRb, PV DNA was amplified from 24. As in previous studies, 24,30 FdPV-2 was the PV most frequently amplified from the feline lesions. The ability of HPVs to interact with pRb is dependent on a LXCXE motif within the E7 gene.…”

“…Multiple PV types, including HPVs, have been detected within feline cutaneous SCCs. 25,29,30 Therefore, while consensus primers were used in this study, it is possible that other PV types were present that were not amplified by these primers. Additionally, the tissues used in the study had been formalin fixed.…”

A Naturally Occurring Feline Model of Head and Neck Squamous Cell Carcinoma

“…In addition, HPV-positive tumors tend to occur in younger people compared with HPV-negative HNSCC which commonly affects older patients. Similarly, most FOSCCs occur in geriatric cats and are HPV-negative [39, 40]. Aberrant p53 expression has been documented in FOSCC and is associated with tobacco smoke exposure [44, 61].…”

Felis catus papillomavirus types 1 and 4 are rarely present in neoplastic and inflammatory oral lesions of cats

“…While it is unknown what causes feline OSCCs, around a quarter of human OSCCs are caused by human papillomaviruses (PVs) (Gillison, 2007). Three previous studies have used consensus PCR primers to detect PV DNA within 1 of 20 (Munday et al, 2009), 2 of 30 (O'Neill et al, 2011), and 0 of 30 (Munday et al, 2011c) feline OSCCs. However, only human PV types were detected in these previous studies and, as PVs are almost always highly species and location specific (Sundberg et al, 2000), the significance of these results is difficult to determine.…”