Analysis of p53 status in tonsillar carcinomas associated with human papillomavirus

Tonsillar squamous cell carcinomas (a total of 14) were examined both for the presence of human papillomavirus (HPV) DNA and for p53 alterations. General primer-mediated HPV polymerase chain reaction (GP-PCR) revealed the presence of HPV DNA in 12/14 cases. Subsequent typing by HPV type-specific PCR and sequence or hybridization analysis of GP-PCR products revealed DNA from HPV 16 in seven cases, from HPV 33 in two cases, and from HPV 7, HPV 16/33 and HPV 33/59 each in a single case. p53 immunohistochemistry performed on nine HPV containing tonsillar carcinomas using polyclonal serum CM-1 showed elevated p53 levels in four cases. These included 3/5 HPV 16 containing carcinomas and the HPV 33/59 containing carcinoma. Analysis of p53 mutations using denaturing gradient gel electrophoresis (DGGE) of GC-clamped PCR products of exons 5 to 8 showed p53 gene alterations in 3/13 cases, incuding 2/11 HPV positive cases and 1/2 HPV negative cases. The alterations included a silent point mutation within exon 8 of an HPV 16 containing carcinoma, a 1 bp deletion within exon 8 of an HPV 33 containing carcinoma, and a missense mutation within exon 7 of one of the HPV negative carcinomas. There was evident discrepancy between p53 immunohistochemistry and gene analysis. Four HPV containing cases showing elevated p53 levels did not reveal the presence of exon 5 to 8 alterations affecting the amino acid code, suggesting the presence of mutations occurring in other exons or non-mutational p53 stabilization. The data indicate that HPV and elevated p53 can coexist in tonsillar carcinomas and that despite the low frequency of p53 mutations the presence of HPV is not exclusively related to the absence of mutated p53

Chitosan-based sleeves loaded with silver and chlorhexidine in a percutaneous rabbit tibia model with a repeated bacterial challenge

Item does not contain fulltex

In vitro and in vivo effects of DNA-based coatings functionalized with vascular endothelial growth factor (VEGF)

Contains fulltext : 34661.pdf (publisher's version ) (Open Access

Humaan papillomavirus en het ontstaan van baarmoederhalskanker: Concept van carcinogenese

Infection with high risk human papillomavirus (hrHPV) plays a central aetiological role in cervical cancer. Still, cervical carcinogenesis is a multistep process which requires other events in addition to hrHPV infection. Recent data have resulted in the following concept of cervical carcinogenesis: hrHPV infects normal squamous epithelium. In most cases this will not lead to a lesion or at worst give rise to a regressing low grade cervical intraepithelial neoplasia (CIN). Both phenomena involve viral clearance. Only persistent hrHPV infections will lead to a high grade CIN lesion, a subset of which may undergo malignant transformation. At the transition of CIN 2 to CIN 3 deregulated expression of the viral oncogenes E6 and E7 takes place, resulting in genetic instability. Subsequently, activation of the telomere-lengthening enzyme, telomerase occurs, as the result of which cells obtain an infinite replication capacity. Ultimately, successive allele losses occur at different chromosomal locations which, followed by a clonal outgrowth result in an invasive carcinoma

In vitro and in vivo evaluation of the inflammatory response to nanoscale grooved substrates

The immune response to an implanted biomaterial is orchestrated by macrophages. In this study various nanogrooved patterns were created by using laser interference lithography and reactive ion etching. The created nanogrooves mimic the natural extracellular matrix environment. Macrophage cell culture demonstrated that interleukin 1β and TNF-α cytokine production were upregulated on nanogrooved substrates. In vivo subcutaneous implantation in a validated mouse cage model for 14 days demonstrated that nanogrooves enhanced and guided cell adhesion, and few multinucleated cells were formed. In agreement with the in vitro results, cytokine production was found to be nanogroove dependent, as interleukin 1β, TNF-α, TGF-β and osteopontin became upregulated. The results indicate that biomaterial surface texturing, especially at the nanometric scale, can be used to control macrophage activation to induce a wound healing response, rather than a profound inflammatory response

In vitro and in vivo evaluation of the inflammatory response to nanoscale grooved substrates.

Item does not contain fulltextThe immune response to an implanted biomaterial is orchestrated by macrophages. In this study various nanogrooved patterns were created by using laser interference lithography and reactive ion etching. The created nanogrooves mimic the natural extracellular matrix environment. Macrophage cell culture demonstrated that interleukin 1beta and TNF-alpha cytokine production were upregulated on nanogrooved substrates. In vivo subcutaneous implantation in a validated mouse cage model for 14 days demonstrated that nanogrooves enhanced and guided cell adhesion, and few multinucleated cells were formed. In agreement with the in vitro results, cytokine production was found to be nanogroove dependent, as interleukin 1beta, TNF-alpha, TGF-beta and osteopontin became upregulated. The results indicate that biomaterial surface texturing, especially at the nanometric scale, can be used to control macrophage activation to induce a wound healing response, rather than a profound inflammatory response. From the Clinical Editor: The authors investigate various nano-grooved patterns that mimic the natural extracellular matrix environment and demonstrate (both in macrophage cultures and in vivo) that interleukin 1beta and TNF-alpha cytokine production is dependent upon surface texturing at the nanometric scale. They propose that modified surfaces may trigger macrophage activation to promote a wound healing response.1 april 201

Telomerase activity exclusively in cervical carcinomas and a subset of cervical intraepithelial neoplasia grade III lesions: Strong association with elevated messenger RNA levels of its catalytic subunit and high-risk human papillomavirus DNA

In this study, we investigated telomerase activity and human telomerase reverse transcriptase (hTERT) mRNA expression in relation to high-risk human papillomavirus (HPV) DNA presence in the spectrum of cervical premalignant lesions. Reconstruction experiments revealed that telomerase activity determined by the telomeric repeat amplification protocol assay and hTERT mRNA by reverse transcriptase-PCR could be detected in down to 100 and 1 SiHa cervical cancer cells, respectively. Telomeric repeat amplification protocol analysis on cervical tissue specimens revealed that none of the histomorphologically normal cervical samples (n = 8) and cervical intraepithelial neoplasia (CIN) grade I (n = 10) and grade II (n = 8) lesions had detectable telomerase activity. However, telomerase activity was shown in 40% of CIN grade III lesions (n = 15) and 96% of squamous cell carcinomas (n = 24). Despite the fact that hTERT mRNA was found at much higher frequencies, semiquantitative reverse transcriptase-PCR revealed that elevated hTERT mRNA levels were strongly correlated with detectable telomerase activity. Furthermore, telomerase activity and elevated hTERT mRNA levels were only detected in cases that contained high-risk HPV DNA. In contrast, low or undetectable hTERT mRNA levels were demonstrated in both high-risk HPV positive and negative cases. These data indicate that telomerase activity detectable with the assay used and concomitant elevated levels of hTERT mRNA reflect a rather late step in the CIN to squamous cell carcinoma sequence, which follows infection with high-risk HPV

Immune responses against human papillomavirus (HPV) type 16 virus-like particles in a cohort study of women with cervical intraepithelial neoplasia. II. Systemic but not local IgA responses correlate with clearance of HPV-16

To investigate whether there is an association between local or systemic IgG and IgA responses against human papillomavirus (HPV) type 16 virus-like particles (VLP) containing L1 and L2 and the possible influence of these responses on clearance of HPV-16 and its associated lesions, cervical mucus samples from 125 patients and plasma samples from 100 patients, all participating in a non-intervention cohort study of women with abnormal cytology, were analysed. The results show that local IgG and IgA HPV-16 VLP-specific antibodies do not correlate with virus clearance. However, systemic IgG responses were more frequently detected in patients with a persistent infection (11/24) compared with patients with cleared HPV-16 infections (3/28, P = 0.006). Furthermore, the ultimate development of high-grade lesions was associated with systemic VLP-specific IgG reactivity (P = 0.026). By contrast, systemic IgA responses were correlated with virus clearance (7/28 clearance compared with 1/24 persistence patients, P = 0.06). This correlation was statistically significant when only those clearance patients who tested HPV-16 DNA-positive at more than one visit were included in the analysis (5/11 compared with 1/24, P = 0.007). As these systemic IgA responses were not accompanied by local IgA responses, the systemic IgA responses in HPV-16 clearance patients are suggested to be a by-product of a successful cellular immune response induced at the local lymph nodes, mediated by cytokines

Lack of granzyme expression in T lymphocytes indicates poor cytotoxic T lymphocyte activation in human papillomavirus-associated cervical carcinomas

Changes in major histocompatibility complex (MHC) class I expression in neoplastic cells are frequently observed in human papillomavirus type 16 (HPV16)-associated cervical carcinomas. In order to investigate whether this affects cytotoxic T-cell (CTL) activation, 20 HPV16-positive cervical carcinomas with variable MHC expression were analyzed immunohistochemically for the expression of granzyme B and interleukin- 2 receptor (IL-2R). The results revealed that most carcinomas show strong CD3+ T-lymphocyte infiltrates. In nine of these cases CD8+ cells outnumbered the CD4+ cells, whereas in the remaining cases equal amounts of CD4+ and CD8+ cells were found. Double staining revealed that CD3+ granzyme B+ cells were not detected in 19 out of 20 cervical lesions, whereas in one carcinoma an occasional cluster of granzyme B+ T cells was observed. Positive controls, including genital warts and renal allograft rejections, showed granzyme B+ T cells. In agreement with this observation was the extremely low frequency of IL-2R+ T cells in the carcinomas tested, while warts contained IL-2R+ lymphocytes. The data indicate that cytotoxic (CD8+) T cells in cervical carcinomas are not activated, as demonstrated by the lack of granzyme B and IL-2R expression in the T cells