Exogenous growth hormone promotes an epithelial-mesenchymal hybrid phenotype in cancerous HeLa cells but not in non-cancerous HEK293 cells

In cancer, the Epithelial to Mesenchymal Transition (EMT) is the process in which epithelial cells acquire mesenchymal features that allow metastasis, and chemotherapy resistance. Growth hormone (GH) has been associated with melanoma, breast, and endometrial cancer progression through an autocrine regulation of EMT. Since exogenous and autocrine expression of GH is known to have different molecular effects, we investigated whether exogenous GH is capable of regulating the EMT of cancer cells. Furthermore, we investigated whether exogenous GH could promote EMT in non-cancerous cells. To study the effect of GH (100 ng/ml) on cancer and non-cancer cells, we used HeLa and HEK293 cell lines, respectively. We evaluated the loss of cell-cell contacts, by cell scattering assay and migration by wound-healing assay. Additionally, we evaluated the morphological changes by phalloidin-staining. Finally, we evaluated the molecular markers E-cadherin and vimentin by flow cytometry. GH enhances cell scattering and the migratory rate and promotes morphological changes such as cell area increase and actin cytoskeleton filaments formation on HeLa cell line. Moreover, we found that GH favors the expression of the mesenchymal protein vimentin, followed by an increase in E-cadherin's epithelial protein expression, characteristics of an epithelial-mesenchymal hybrid phenotype that is associated with metastasis. On HEK293cells, GH promotes morphological changes, including cell area increment and filopodia formation, but not affects scattering, migration, nor EMT markers expression. Our results suggest that exogenous GH might participate in cervical cancer progression favoring a hybrid EMT phenotype but not on non-cancerous HEK293 cells.

MicroRNA and Hemophilia-A Disease: Bioinformatics Prediction and Experimental Analysis

Objective

Hemophilia-A is a common genetic abnormality resulted from decreased or lack of factor VIII (FVIII) pro-coagulant protein function caused by mutations in the F8 gene. Majority of molecular studies consider screening of mutations and their relevant impacts on the quality and expression levels of FVIII. Interestingly, some of the functions in FVIII suggest a probable involvement of small non-coding RNAs embedded within the sequence of F8 gene. Therefore, microRNAs which are encoded within the F8 gene might have a role in hemophilia development. In this study, miRNAs production in the F8 gene was investigated by bioinformatics prediction and experimental validation.

Materials and Methods

In this experimental study, bioinformatics tools have been utilized to seek the novel microRNAs inserted within human F8 gene. The ability to express new microRNAs in F8 locus was studied through reliable bioinformatics databases such as SSCProfiler, RNA fold, miREval, miR-FIND, UCSC genome browser and miRBase. Then, expression and processing of the predicted microRNAs were examined based on bioinformatics methods, in the HEK293 cell lines.

Results

We are unable to confirm existence of the considered mature microRNAs in the transfected cells.

Conclusion

We hope that through changing experimental conditions, designing new primers or altering cell lines as well as the expression of vectors, exogenous and endogenous expressions of the predicted miRNA will be confirmed.

Lentiviral-mediated BCL2 gene knockdown using comparative microRNA adaptive shRNAs

B-cell lymphoma 2 (BCL2) family proteins play a critical role in tuning cell death processes. Almost in half of all human cancers, a dysregulation in BCL2 family gene expression has been shown which made it an impressive target for human gene therapy as a novel approach in cancers. In this study we will optimize lentiviral-mediated RNA interference (RNAi), recombinant lentiviruses accommodating anti-BCL2 micro adaptive short hairpin RNAs (shRNAs), to downregulate BCL2 in human embryonic kidney 293T (HEK293T) cells to produce stable cell lines. We tested 4 different Dharmacon™ GIPZ™ shRNAmir lentiviral vectors targeting BCL2 in different positions and a pGIPZ non-silencing shRNAmir lentiviral vector (as a negative control). Lentivirus packaging was performed by the calcium phosphate precipitation method. HEK293T cells were transduced by each type of recombinant lentiviruses individually and selected by puromycin within 10 days. The relative mRNA level and protein expression were assayed by using real-time polymerase chain reaction (PCR) technic and western blotting, respectively. Lentivirus (LV) packaging was performed in high efficiency (transfection rate was > 90%). Recombinant viruses of 4 expression vector addition to a control vector were produced then transduced to HEK293T cells successfully. All the 4 cell groups showed a significant down regulation of BCL2 gene (~90-95%) at mRNA level compared to the control group (p<0.01) but differences between silenced groups were not significant (P > 0.05). We showed that the lentivirus-mediated RNAi technique is an efficient method to establish HEK293 cell lines with stable down-regulation of BCL2 gene.

Deorphanization and characterization of human olfactory receptors in heterologous cells

Olfaction plays an indispensable role in human and animals in self and environmental recognition, as well as intra- and interspecific communication. Following the discovery of a family of olfactory receptors (ORs) by Buck and Axel in 1991, it has been established that the sense of smell begins with the molecular recognition of a chemical odorant by one or more ORs expressed in the olfactory sensory neurons. Therefore, characterization of the molecular interactions between odorant molecules and ORs is a key step in the elucidation of the general properties of the olfactory system and in the development of applications, i.e., design of new odorants, search for blockers, etc. The process putted in place at ChemCom to improve the expression of ORs at the cytoplasmic membrane of the HEK293 cell and assays enabling large-scale deorphanization, and to characterize the interaction between chemical odorants and ORs is described. The family of human ORs includes ca. 400 putatively functional ORs which are GPCRs (G protein-coupled receptors); to date over 100 human ORs have been deorphanized.