Gene expression profiles induced by E6 from non-European HPV18 variants reveals a differential activation on cellular processes driving to carcinogenesis

AbstractCervical cancer in developed countries remains as a major concern on public health policies due to incidence and mortality rates. Persistent infection with high risk human papillomavirus is a necessary etiological agent in the progression to invasive cervical carcinoma. A proposed hypothesis is the association between more aggressive HPV variants and the risk to develop cervical cancer. In order to have a global perspective in terms of cellular transcripts and molecular pathways affected by HPV18 E6 intratype variants; we conducted a genome wide analysis of gene expression. Our results show that E6 derived from non-European variants are able to up-regulate cellular transcripts associated to the hallmarks of cancer; such as cell cycle, migration, Wnt pathway and mTor signaling. Moreover, we were able to show that HPV18 E6 from African variant had a major effect on cellular processes such as cell cycle and migration as confirmed by functional studies

Full-Exon Pyrosequencing Screening of BRCA Germline Mutations in Mexican Women with Inherited Breast and Ovarian Cancer

Hereditary breast cancer comprises 10% of all breast cancers. The most prevalent genes causing this pathology are BRCA1 and BRCA2 (breast cancer early onset 1 and 2), which also predispose to other cancers. Despite the outstanding relevance of genetic screening of BRCA deleterious variants in patients with a history of familial cancer, this practice is not common in Latin American public institutions. In this work we assessed mutations in the entire exonic and splice-site regions of BRCA in 39 patients with breast and ovarian cancer and with familial history of breast cancer or with clinical features suggestive for BRCA mutations by massive parallel pyrosequencing. First we evaluated the method with controls and found 41–485 reads per sequence in BRCA pathogenic mutations. Negative controls did not show deleterious variants, confirming the suitability of the approach. In patients diagnosed with cancer we found 4 novel deleterious mutations (c.2805_2808delAGAT and c.3124_3133delAGCAATATTA in BRCA1; c.2639_2640delTG and c.5114_5117delTAAA in BRCA2). The prevalence of BRCA mutations in these patients was 10.2%. Moreover, we discovered 16 variants with unknown clinical significance (11 in exons and 5 in introns); 4 were predicted as possibly pathogenic by in silico analyses, and 3 have not been described previously. This study illustrates how massive pyrosequencing technology can be applied to screen for BRCA mutations in the whole exonic and splice regions in patients with suspected BRCA-related cancers. This is the first effort to analyse the mutational status of BRCA genes on a Mexican-mestizo population by means of pyrosequencing

Variants of uncertain significance (VUS) detected in patients.

1<p>D: deletion; M: missense mutation; S: synonimous mutation; Ts: transition; Tv: transvertion.</p>2<p>B: benign; PD: probably damaging.</p

Evaluation of the methodological strategy for the detection of BRCA mutations.

1<p>Number of reads per nucleotide.</p>a<p>Types of mutations: F: frameshift; S: stop.</p

Detection of BRCA deleterious mutations in patients.

1<p>Number of reads per nucleotide.</p>2<p>Types of mutations: F: frameshift; S: stop.</p

Distribution of homopolymeric tracts across the reads.

<p>The base number signals are plotted against the sequence reads of the control run.</p

Genealogy of the family 15 carrier of the deleterious mutation c.2639_2640delTG in <i>BRCA2</i>.

<p>Individuals with cancer are represented with dark circles or with dark squares; the type of cancer is indicated as follows: Br: unilateral breast cancer; Cr: colorectal cancer; NE: Not especified neoplasia; L: lung cancer; La: laryngeal cancer; Ga: gastric cancer. Index patient is denoted with an arrow. Current age or known ages of cancer diagnosis and decease are showed. Numbers inside the rhombi indicate quantity of first-degree relatives. Asymptomatic carriers are represented with a midline.</p

Clinical features of the patients with <i>BRCA</i> mutations.

a<p>ER  =  estrogen receptor; PR  =  progesterone receptor; HER2/neu  =  human epidermal growth factor receptor 2; Ki-67 =  antigen KI 67.</p

Genealogy of the family 1 carrier of the deleterious mutation c.5114_5117delTAAA in <i>BRCA2</i>.

<p>Index patient is denoted with an arrow. Individuals with cancer are represented with in dark circles or with dark squares; the type of cancer is indicated as follows: Bla: Bladder cancer; Br: Unilateral Breast Cancer; B-Br: Bilateral breast cancer. Current age or known ages of cancer diagnosis and decease are showed. Numbers inside the rhombi indicate quantity of relatives. Asymptomatic carriers are represented with a midline. Unaffected family members confirmed by the predictive molecular testing are shown with a W (wild type).</p