Enoc Mariano Cortés-Malagón

The E6 Oncoprotein from HPV16 Enhances the Canonical Wnt/β-catenin Pathway in Skin Epidermis in vivo.

The contribution of the Wnt signaling pathway to human papilloma virus (HPV)-induced carcinogenesis is poorly understood. In high-grade dysplastic lesions that are caused by high-risk HPVs (HR-HPV), β-catenin is often located in the cell nucleus, which suggests that Wnt pathway may be involved in the development of HPV-related carcinomas. Most of the oncogenic potential of HR-HPVs resides on the PDZ-binding domain of E6 protein. We hypothesized that the PDZ-binding domain of the HPV16-E6 oncoprotein induces the nuclear accumulation of β-catenin due to its capacity to degrade PDZ-containing cellular targets. To test this hypothesis, we evaluated the staining pattern of β-catenin in the skin epidermis of transgenic mice expressing the full-length E6 oncoprotein (K14E6 mice) and measured LacZ gene expression in K14E6 mice that were crossed with a strain expressing LacZ that was knocked into the Axin2 locus (Axin2+/LacZ mice). Here, we show that the E6 oncoprotein enhances the nuclear accumulation of β-catenin, the accumulation of cellular β-catenin–responsive genes, and the expression of LacZ. None of these effects were observed when a truncated E6 oncoprotein that lacks the PDZ-binding domain was expressed alone (K14E6ΔPDZ mice) or in combination with Axin2+/LacZ. Conversely, cotransfection with either E6 or E6ΔPDZ similarly enhanced canonical Wnt signaling in short-term in vitro assays that used a luciferase Wnt/β-catenin/TCF-dependent promoter. We propose that the activation of canonical Wnt signaling could be induced by the HPV16-E6 oncoprotein; however, the participation of the E6 PDZ-binding domain seems to be important in in vivo models only. Mol Cancer Res; 10(2); 250–8. ©2011 AACR.

Gene expression profile regulated by the HPV16 E7 oncoprotein and estradiol in cervical tissue.

The HPV16 E7 oncoprotein and 17β-estradiol are important factors for the induction of premalignant lesions and cervical cancer. The study of these factors is crucial for a better understanding of cervical tumorigenesis. Here, we assessed the global gene expression profiles induced by the HPV16 E7 oncoprotein and/or 17β-estradiol in cervical tissue of FvB and K14E7 transgenic mice. We found that the most dramatic changes in gene expression occurred in K14E7 and FvB groups treated with 17β-estradiol. A large number of differentially expressed genes involved in the immune response were observed in 17β-estradiol treated groups. The E7 oncoprotein mainly affected the expression of genes involved in cellular metabolism. Our microarray data also identified differentially expressed genes that have not previously been reported in cervical cancer. The identification of genes regulated by E7 and 17β-estradiol, provides the basis for further studies on their role in cervical carcinogenesis.

Differential gene expression between skin and cervix induced by the E7 oncoprotein in a transgenic mouse model

HPV16 E7 oncoprotein expression in K14E7 transgenic mice induces cervical cancer after 6 months of treatment with the co-carcinogen 17β-estradiol. In untreated mice, E7 also induces skin tumors late in life albeit at low penetrance. These findings indicate that E7 alters cellular functions in cervix and skin so as to predispose these organs to tumorigenesis. Using microarrays, we determined the global genes expression profile in cervical and skin tissue of young adult K14E7 transgenic mice without estrogen treatment. In these tissues, the E7 oncoprotein altered the transcriptional pattern of genes involved in several biological processes including signal transduction, transport, metabolic process, cell adhesion, apoptosis, cell differentiation, immune response and inflammatory response. Among the E7-dysregulated genes were ones not previously known to be involved in cervical neoplasia including DMBT1, GLI1 and 17βHSD2 in cervix, as well as MMP2, 12, 14, 19 and 27 in skin.

The HPV16 E7 Oncoprotein Disrupts Dendritic Cell Function and Induces the Systemic Expansion of CD11b+Gr1+ Cells in a Transgenic Mouse Model

Objective. The aim of this study was to analyze the effects of the HPV16 E7 oncoprotein on dendritic cells (DCs) and CD11b+Gr1+ cells using the K14E7 transgenic mouse model. Materials and Methods. The morphology of DCs was analyzed in male mouse skin on epidermal sheets using immunofluorescence and confocal microscopy. Flow cytometry was used to determine the percentages of DCs and CD11b+Gr1+ cells in different tissues and to evaluate the migration of DCs. Results. In the K14E7 mouse model, the morphology of Langerhans cells and the migratory activity of dendritic cells were abnormal. An increase in CD11b+Gr1+ cells was observed in the blood and skin of K14E7 mice, and molecules related to CD11b+Gr1+ chemoattraction (MCP1 and S100A9) were upregulated. Conclusions. These data suggest that the HPV16 E7 oncoprotein impairs the function and morphology of DCs and induces the systemic accumulation of CD11b+Gr1+ cells.

Human papillomavirus type 16 E7 oncoprotein upregulates the retinoic acid receptor-beta expression in cervical cancer cell lines and K14E7 transgenic mice

Persistent infection with high-risk human papillomaviruses is the main etiological factor in cervical cancer (CC). The human papillomavirus type 16 (HPV16) E7 oncoprotein alters several cellular processes, regulating the expression of many genes in order to avoid cell cycle control. Retinoic acid receptor beta (RARB) blocks cell growth, inducing differentiation and apoptosis. This tumor suppressor gene is gradually silenced in late passages of foreskin keratinocytes immortalized with HPV16 and in various tumors, including CC, mainly by epigenetic modifications. We investigated the effect of E7 oncoprotein on RARB gene expression. We found that HPV16 E7 increases RARB mRNA and RAR-beta protein expression both in vitro and in the cervix of young K14E7 transgenic mice. In E7-expressing cells, RARB overexpression is further increased in the presence of the tumor suppressor p53 (TP53) R273C mutant. This effect does not change when either C33-A or E7-expressing C33-A cell line is treated with Trichostatin A, suggesting that E7 enhances RARB expression independently of histone deacetylases inhibition. These findings indicate that RARB overexpression is part of the early molecular events induced by the E7 oncoprotein.

Early synergistic interactions between the HPV16‑E7 oncoprotein and 17β-oestradiol for repressing the expression of Granzyme B in a cervical cancer model

Although high-risk human papillomavirus (HR-HPV) infection has a prominent role in the aetiology of cervical cancer (CC), sex steroid hormones may also be involved in this process; however, the cooperation between oestrogen and HR-HPV in the early stages of cervical carcinogenesis is poorly understood. Since 17β-oestradiol (E2) and the HPV type 16-E7 oncoprotein induce CC in transgenic mice, a microarray analysis was performed in the present study to generate global gene expression profiles from 2-month-old FVB (non-transgenic) and K14E7 (transgenic) mice who were left untreated or were treated for 1 month with E2. Upregulation of cancer-related genes that have not been previously reported in the context of CC, including glycerophosphodiester phosphodiesterase domain containing 3, interleukin 1 receptor type II, natriuretic peptide type C, MGAT4 family member C, lecithin-retinol acyltransferase (phosphatidylcholine-retinol-O-acyltransferase) and glucoside xylosyltransferase 2, was observed. Notably, upregulation of the serine (or cysteine) peptidase inhibitor clade B member 9 gene and downregulation of the Granzyme gene family were observed; the repression of the Granzyme B pathway may be a novel mechanism of immune evasion by cancer cells. The present results provide the basis for further studies on early biomarkers of CC risk and synergistic interactions between HR-HPV and oestrogen.

The PDZ-Binding Motif of HPV16-E6 Oncoprotein Modulates the Keratinization and Stemness Transcriptional Profile In Vivo

Objective The aim of this work was to compare the early gene expression profiles in the skin of HPV16-E6 transgenic mice regulated by the E6 PDZ-binding motif. Materials and Methods The global transcriptional profiles in dorsal skin biopsies from K14E6 and K14E6Δ146-151 transgenic mice were compared using microarrays. Relevant genes obtained from the most differentially expressed processes were further examined by RT-qPCR, in situ RT-PCR, Western blot, or immunofluorescence. Results The transcriptomic landscape of K14E6 versus K14E6Δ146-151 shows that the most affected expression profiles were those related to keratinocyte differentiation, stem cell maintenance, and keratinization. Additionally, downregulation of epidermal stemness markers such as K15 and CD34, as well as the upregulation of cytokeratin 6b, appeared to be dependent on the E6 PDZ-binding motif. Finally, wound healing, a physiological process linked to stemness, is impaired in the K14E6 mice compared to K14E6Δ146-151. Conclusion The E6 PDZ-binding motif appears to affect stemness and keratinization during early stages of skin carcinogenesis. As E6 plays a significant role in HPV-induced skin carcinogenesis, the K14E6 versus K14E6Δ146-151 transcriptional profile provides a source of valuable data to uncover novel E6 functions in the skin.

Skeletal manifestations of Marfan syndrome associated to heterozygous R2726W FBN1 variant: sibling case report and literature review

BackgroundFBN1 (15q21.1) encodes fibrillin-1, a large glycoprotein which is a major component of microfibrils that are widely distributed in structural elements of elastic and non-elastic tissues. FBN1 variants are responsible for the related connective tissue disorders, grouped under the generic term of type-1 fibrillinopathies, which include Marfan syndrome (MFS), MASS syndrome (Mitral valve prolapse, Aortic enlargement, Skin and Skeletal findings, Acromicric dysplasia, Familial ectopia lentis, Geleophysic dysplasia 2, Stiff skin syndrome, and dominant Weill-Marchesani syndrome.Case presentationTwo siblings presented with isolated skeletal manifestations of MFS, including severe pectus excavatum, elongated face, scoliosis in one case, and absence of other clinical features according to Ghent criteria diagnosis, were screened for detection of variants in whole FBN1 gene (65 exons). Both individuals were heterozygous for the R2726W variant. This variant has been previously reported in association with some skeletal features of Marfan syndrome in the absence of both tall stature and non-skeletal features. These features are consistent with the presentation of the siblings reported here.ConclusionThe presented cases confirm that the R2726W FBN1 variant is associated with skeletal features of MFS in the absence of cardiac or ocular findings. These findings confirm that FBN1 variants are associated with a broad phenotypic spectrum and the value of sequencing in atypical cases.