Jean Luc Prétet

Detection of alpha- and beta-human papillomavirus (HPV) in cutaneous melanoma: a matched and controlled study using specific multiplex PCR combined with DNA microarray primer extension.

Abstract:  There are few contradictory studies investigating the involvement of HPV in melanoma. We designed a controlled study to evaluate the HPV DNA prevalence in melanoma. One hundred patients with cutaneous malignant melanoma diagnosed between 2002 and 2006 were included. Complementary wide excision (healthy skin) was performed in 85 patients and was used as internal control. After DNA extraction, 68 different HPV types were studied using a multiplex PCR combined with microarray primer extension. We did not observe any statistical significant difference in terms of HPV DNA prevalence in melanoma (38.8%) and in healthy skin from wide excision (42.4%). Twenty‐one different HPV types were detected but only one type was present in the majority of our samples (80/85 melanoma vs 59/66 HS). The distribution of HPV genera and types was similar in melanoma and HS, and beta‐HPV was predominant (30.6% and 31.8%). Among alpha‐HPV (10.6%), high‐risk mucosal HPV16 was predominant. Among beta‐HPV, melanoma harboured significantly more type 22 than control normal skin from the same patients and significantly less type 21 than paired control normal skin. No correlation between clinical and pathological melanoma characteristics and HPV DNA prevalence was found. Our data do not support a role of HPV infection in melanocarcinogenesis, but confirm the previous data suggesting that HPV DNA is widely distributed among the population and that occult HPV infections are frequent. Furthermore, specific HPV types, such as a‐HPV16 and beta‐HPV species 2 may be involved in a sub‐group of melanoma.

TP53 polymorphism at exon 4 in caucasian women from eastern France: lack of correlation with HPV status and grade of cervical precancerous lesions

OBJECTIVE To investigate the codon 72 TP53 polymorphism in women from eastern France with normal or abnormal cervical cytology. STUDY DESIGN We analyzed the TP53 allele distribution by denaturant gradient gel electrophoresis assay and the human papillomaviruses (HPV) infection in 138 cervical smears: 50 normal, 20 atypical squamous cells of undetermined significance, 40 low grade squamous intraepithelial lesions, 28 high grade squamous intraepithelial lesions. RESULTS The viral DNA prevalence increased with cytological abnormalities. The rates of arginine (Arg) and proline (Pro) homozygosity and Arg/Pro heterozygosity were 49, 0.72, and 51%, respectively. No association was found between HPV status and TP53 polymorphism. No differences were observed in the frequency of the TP53 genotypes according to cytology. CONCLUSION The TP53 Arg/Arg genotype does not appear to represent a risk factor in the progression of HPV associated cervical lesions. We were not able to confirm that the TP53 genotype increases the susceptibility to be infected by HPV or to develop HGSIL, and a fortiori invasive carcinoma of the cervix.

Detection of human papillomavirus DNA in plucked eyebrow hair from HIV-infected patients.

function of the CLE is still unclear, a role as a necessary scaffold for the lamellar bilayer organization is likely (Uchida and Holleran, 2008). Thus, CLE deficiency, coupled with disorganization of extracellular lamellar bilayers, likely merge to provoke the barrier abnormality in NLSDI (see Supplementary Figure S2 online). Finally, to overcome this metabolic disadvantage in forming the epidermal permeability barrier, epidermal proliferation likely increases, which in turn results in hyperkeratosis, phenotypic features common to virtually all of the ichthyoses (Demerjian et al., 2006; Akiyama et al., 2008), that is, ‘A compromised permeability barrier ‘drives’ the hyperproliferative epidermis in NLSDI and other ichthyoses’ (Elias et al., 2008).

BRAF mutation screening in melanoma: is sentinel lymph node reliable?

As the detection of the BRAF V600E mutation has a direct impact on treatment decision, an accurate screening for BRAF mutations in patients with advanced or metastatic melanoma is mandatory. Nevertheless, BRAF oncogene mutation status between different samples from the same patient has been studied with conflicting results. This study investigated the intrapatient homogeneity of BRAF mutation status using pyrosequencing in primary tumors and different metastatic sites of melanoma patients. Paired samples of lymphatic, visceral, and subcutaneous metastases and primary melanoma from 45 metastatic melanoma patients were tested for BRAF mutations using a pyrosequencing assay and by Sanger sequencing. Overall, sequencing for BRAF mutation status was performed in 114 paired samples from 45 patients. Eighteen patients (40%) carried a BRAF mutation, including BRAF V600E (12/18), BRAF V600K (5/18), and BRAF V600R (1/18) mutations. Multiple BRAF mutations (V600E and V600K) were found in one patient. Among the patients with BRAF mutations, a good agreement in BRAF mutation status was found between the first and second tumor samples genotyped (91%; Cohen’s &kgr; coefficient: 0.81). Discordance in BRAF mutation status was found only in four patients, involving all three patients in whom sentinel lymph node (SLN) metastases were sampled. These SLNs exhibited a wild-type genotype and were discordant with the other BRAF-mutated samples found in the same patient. The intrapatient BRAF status was predominantly homogeneous. However, SLN genotyping using pyrosequencing might be inaccurate in determining the actual mutation status of melanoma. Further studies are required to confirm the lack of reliability of SLN.

Effect of Infliximab on the UVB-Induced Apoptosis of Keratinocytes Infected by HPV38 E6/E7

The question of the effect of anti-TNF-alpha in skin carcinogenesis is especially relevant in view of the increased use of these drugs for the treatment of autoinflammatory immune diseases. Since ultraviolet radiation and human papillomavirus are involved in skin carcinogenesis, we wished to investigate the effect of TNF-alpha antagonists on the UVB-induced apoptosis of keratinocytes infected by HPV38. Our results indicate that anti-TNF agent, infliximab, does not contribute to the survival of HPV38-transduced keratinocytes with UVB-induced DNA damages.