Yoshiro Yabe

Human papillomavirus type 16 DNA detected by the polymerase chain reaction in non-cancer tissues of the head and neck

Cancer-free tissues from various anatomical subsites in the head and neck were examined by the polymerase chain reaction (PCR) for the incidence of human papillomavirus (HPV) types 16 and 18. We detected HPV 16 DNA in 9 of 103 samples (8.7%), including specimens from the paranasal sinuses, tonsil, hypopharynx and larynx. However, no HPV-16/18 DNA was detected by Southern hybridization in these 9 samples. The significance of the presence of HPV 16 DNA in non-cancer tissues is still unknown, but PCR detection only of high-risk HPV DNA in head and neck cancer should be evaluated cautiously because of its ubiquity in this region.

Comparison of Virapap filter hybridization with polymerase chain reaction and Southern blot hybridization methods for detection of human papillomavirus in tonsillar and pharyngeal cancers.

SummaryA method using a commercial dot filter hybridization kit, Virapap, was compared with Southern blot hybridization and polymerase chain reaction (PCR) for the detection of human papillomavirus (HPV) types 16 and 18 in pharyngeal and tonsillar cancers of 12 patients as well as tonsillar biopsies from 28 patients with chronic tonsillitis. Concordant results between Virapap and PCR, Virapap and Southern hybridization, and PCR and Southern hybridization methods were obtained respectively in 41.7%, 58.3% and 83.3% of the cancer cases, and 67.9%, 67,9% and 85.7% of the control (tonsillitis) cases. Virapap false-positive results were found in 5 cancer cases and 5 control cases. Although the Virapap method is reported to be useful for detecting HPV in gynecological tissues, this method cannot be recommended for the detection of HPV in pharyngeal and tonsillar cancers.

A subtype of human papillomavirus 5 (HPV-5b) and its subgenomic segment amplified in a carcinoma: Nucleotide sequences and genomic organizations☆

A subtype of human papillomavirus 5 (HPV-5b) is closely associated with carcinomas in the disease epidermodysplasia verruciformis (EV). The complete genome was cloned from virus particles in benign lesions of a patient with EV and sequenced: it was 7779 nucleotides long and consisted of six open reading frames (ORFs) (E6, E7, E1, E2, E4, and E5) in the early region, three ORFs (L2, L3, and L1) in the late region, and a noncoding region, all existing on one DNA strand. The 40% segment of the HPV-5b genome specifically amplified in carcinomas was cloned from a primary carcinoma of the same EV patient and sequenced: it was 3143 nucleotides long and corresponded to a segment of the original HPV-5b genome containing the entire sequences of E6, E7, and the noncoding region and portions of E1 and L1. Compared to the whole genomic DNA, no mutations were detected in this probable malignancy-associated viral subgenomic segment cloned from carcinoma. These results suggest that amplification of the viral segment containing E6, E7, and the noncoding region may play a role in the malignant conversion of HPV-5b-infected benign lesions and that mutations in these genes or regions are not necessarily required.

Connection between capsomeres in human papilloma virus.

Abstract Electron microscopic observation of empty, disrupted, and full particles of human papilloma virus suggested that the capsomeres of this virus were not in direct contact with each other, but were connected at their base by two bridges of the size about 35A long and 13A wide, forming an icosadeltahedral shell.

Morphological changes of nucleoli in condylomata acuminata

In large condylomata acuminata of a man of 56 years of age, besides clear virus particles, electron-dense virus-like granules were observed in the nucleus of cells in the stratum corneum. Electron microscopic studies of the cells of all epidermal layers suggested that these virus-like granules were the fragments of disrupted nucteoli. These results are reported in this paper. Ultrathin sections and tissue extracts were prepared and observed electron microscopically as described previously [6]. Cells of the stratum basale and the stratum spinosum had two or more nucleoli or a single very large nucleolus with filamentous structure (Fig. 1). In cells of the stratum intermedium, particularly in its upper layer, nucleoli lost their filamentous structure (Fig. 2). In cells of the lower stratum corneum, nucleoli became small and increased their electron density, and fine mesh-like cracks appeared in them (Figs. 3 and 4). Some nucleoli appeared to be further disrupting, dispersing their fragments of 30 -60 nm. In cells of the middle stratum corneum, nucleoli appeared to be completely disrupted into small fragments, though they still kept the nucleolar outline (Fig. 5). In cells of the upper stratum corneum, the aggregates of nucleolar fragments were observed in the nucleus, but their nucleolar outline was completely lost (Fig. 6). In the cell layer where nucleoli started disruption, viral particles also started appearing in the nucleus. Viral particles were about 40 nm in size and less electrondense than nucleolar fragments (Figs. 4 6). In some cells both disrupting nucleoli or nucleolar fragments and viral particles were observed (Figs. 4 6), but in others only disrupting nucleoli or nucleolar fragments were observed (Figs. 3 and 6). In negatively stained tissue extracts, viral particles were observed, which were about 56 nm in diameter and resembled the virus of common human warts (Fig. 7). The nucleolar fragments were not identified in the tissue extract. In ultrathin sections, viral particles were rather easily distinguished from nucleolar fragments by their uniform size and shape and lower electron density. However, when cells had only nucleolar fragments, or when sections were thick, the

Human papillomavirus in laryngeal papilloma detected by dot blot hybridization (Vira Pap) and southern blot hybridization.

We demonstrated the presence of human papillomavirus (HPV) in 3 of 4 patients with laryngeal papillomas by dot blot hybridization (Vira PapTM) and Southern blot hybridization.1. The HPV was type 6 in 2 patients and type 11 in 1 patient.2. The results of this simple detection test (Vira PapTM kit) for dot blot hybridization correlated well with that of Southern blot hybridization. Therefore, this method is useful as a screening test.3. Dot blot hybridization using serial dilutions of the homogenate of a HPV-positive papilloma revealed that 0.125mg wet weight of the papilloma sample was enough for HPV detection.