[Detection of DNA of human papillomaviruses (HPV) in an "aggressively" growing cholesteatoma. Is cholesteatoma a virus-induced tumor?]. / Nachweis der DNS humaner Papillomviren (HPV) in einem "aggressiv" wachsenden Cholesteatom. Das Cholesteatom, ein virusinduzierter Tumor?

It is yet unknown why under certain circumstances the benign epithelium covering the outer ear canal in a protective role causes an erosion of bony structures after migration into the middle ear. Histologically, a papillomatous growth and clusters of koilocytes are typical features of the aggressively growing, bone-destructive areas of the cholesteatoma. Since these resemble the characteristics of a papilloma, biopsies originating from cholesteatomas were examined for the presence of human papillomavirus (HPV) DNA. Findings demonstrated that HPV-11-related DNA was present in one such lesion. In general, papilloma viruses need specific conditions to be able to replicate and induce a papillomatous growth. Retraction pockets of epithelium, junction lines between squamous epithelium and mucosa as well as inflammatory processes may stimulate this replication. Because these conditions are characteristic for cholesteatoma, we therefore suggest a possible papillomavirus etiology for the development of aggressive cholesteatoma.

Human-papillomavirus DNA in cholesteatomas.

Cholesteatoma of the middle ear is a relatively common disorder, often with severe consequences. Histologically, the aggressively growing, bone-destructing form shows papillary growth and koilocytosis, which are characteristic of papillomavirus-induced lesions. A PCR (polymerase chain reaction) method using degenerate primers for the detection of any known or as yet unknown HPV (human papillomavirus) type was applied in screening 51 biopsies from 42 patients. A resulting 36% (16/45) of the cholesteatomas were found to contain papillomavirus DNA, which hybridized under stringent conditions with an HPV-II DNA probe. In 3 cases the presence of HPV-II DNA could be confirmed by sequencing the PCR products. The mere presence of this HPV DNA does not prove an etiological role of this group of viruses in the induction of cholesteatomas. It does, however, identify another group of human proliferative lesions putatively linked to papillomavirus infections.

Integration of human papillomavirus type 6a DNA in a tonsillar carcinoma: chromosomal localization and nucleotide sequence of the genomic target region.

Human papillomavirus type 6a (HPV 6a) DNA was detected in a tonsillar carcinoma both as integrated and episomal molecules, and one viral-cellular junction was molecularly cloned (Bercovich et al., J. Gen Virol., 72: 2569-2572, 1991). The cellular sequence was used as a probe for the isolation of a cosmid from a normal human genomic DNA library. A 2.7-kilobase subclone including the integration site was sequenced. It was shown to contain sequences with similarities to the E2 and L2 regions of human papillomaviruses, a 5' truncated long interspersed repeated DNA element type 1 retrotransposon, and a fragment of an O-repeat element. The chromosomal localization of the integration site was determined to be at region 24 of the long arm of chromosome 10 (10q24). This is the region where the fragile site is located in which HPV 18 DNA is integrated in the cell line FEP18-5. In addition it contains the site of breakpoints affecting protooncogenes Hox11 and Lyt10. Other genes related to cell division and DNA repair have also been mapped to this chromosomal band. Analysis of genomic DNA of cell lines and patients using 10q24-derived probes is presented. The integration of human papillomavirus type 6 DNA into chromosome 10q24 may have disrupted a cellular gene critical for normal cell growth, which further analysis should help to identify.

[Demonstration and organizational structure of the DNA of human papillomaviruses in laryngeal and hypopharyngeal carcinomas]. / Nachweis und Organisationsstruktur der DNS menschlicher Papillomviren beim Kehlkopf- und Hypopharynxkarzinom.

Thirty biopsy specimens from various histological types of human carcinomas of the larynx and hypopharynx were analysed for the presence of human papillomavirus (HPV) DNA: DNA from the individual specimens were tested for the presence of homologous sequences to HPV genotypes 1, 2, 4, 8, 9, 10, 11, 13, 16 and 18. One squamous cell carcinoma of the hypopharynx (postcricoideal area) contained multiple copies of DNA hybridizing under stringent conditions with HPV 16 DNA. The latter DNA has been found to be frequently associated with human genital cancer. HPV 16 DNA was found mostly episomally as oligomeric circles of 7.9 kbp size, and as larger rear-ranged circular molecules. Integration of the viral DNA in the host cell DNA seems quite likely. Integration and rearrangement of viral DNA into cellular DNA may play a role in the induction and maintenance of the transformed state. The presence of sequences reacting under semistringent conditions with HPV DNA was observed in two additional biopsy specimens of this study. This could suggest that additional laryngeal cancers are associated with papilloma virus infections.

Rearranged HPV 16 molecules in an anal and in a laryngeal carcinoma.

By hybridization under stringent conditions, one out of two anal carcinomas and one out of 36 laryngeal carcinomas were shown to harbor HPV 16 DNA in high copy number. Further analysis of both tumor DNAs indicated a rearrangement of the viral DNA in the tumor cells. HPV 16 DNA in the anal carcinoma could chiefly be found episomally in two different forms: a minority as 7.9-kb oligomeric episomes with no apparent modifications; as 10.7-kb rear-ranged oligomeric episomes with a duplication of the part of the viral genome encoding the open reading frames (ORF) E7, E1 and parts of E6 and E2. In the laryngeal carcinoma, integrated and episomal HPV 16 DNA molecules of 7.9 kb were present, together with rearranged molecules of approximately 18 kb with multiple duplications of the ORF E4 and parts of the ORFs E2, E5, L1 and L2. Possible consequences for transcription of the modified viral genomes are discussed.

Human papillomavirus type 16 related DNA in an anaplastic carcinoma of the lung.

Twenty-four biopsy specimens from various histologic types of human carcinomas in the lung were analyzed for the presence of human papillomavirus (HPV) DNA. DNA from the individual specimens was tested for the presence of homologous sequences to HPV genotypes 1, 2, 4, 8, 9, 10, 11, 13, 16 and 18. One anaplastic carcinoma in the lung contained multiple copies of DNA hybridizing under stringent conditions to HPV 16 DNA. The latter DNA has been found to be frequently associated with human genital cancer (cervical, penile, and vulval cancer) and genital Bowen's disease. The HPV 16 positive lung tumor originated from a 61-year-old female patient who underwent hysterectomy due to cervical cancer 9 years earlier.

Structure and transcription of human papillomavirus sequences in cervical carcinoma cells.

DNA of human papillomavirus (HPV) types 16 and 18 has been found closely associated with human genital cancer, supporting the concept that members of this virus group are key factors in the aetiology of genital cancer. HPV 18 DNA sequences were also detected in cell lines derived from cervical cancer. We have now analysed these cell lines, HeLa, C4-1 and 756, for the structural organization and transcription of the HPV 18 genome and we find that the HPV 18 DNA is integrated into the cellular genome and is amplified in HeLa and 756 cells. Almost the complete HPV 18 genome seems to be present in 756 cells, with the early region being disrupted into two portions in each integrated copy. In HeLa and C4-1 cells, a 2-3 kilobase (kb) segment of HPV 18-specific sequences is missing from the E2 to L2 region. HPV 18 sequences are specifically transcribed from the E6-E7-E1 region into poly(A)+ RNAs of 1.5-6.5 kb. Hybridization analysis of cDNA clones indicated that some of the transcripts are composed of HPV 18 and cellular sequences. In addition, poly(A)+ RNA hybridizing with HPV 16 DNA was found in two out of three cervical carcinoma biopsies.