In vitro induction of hair follicle signatures using human dermal papilla cells encapsulated in fibrin microgels.

Cellular spheroids have been described as an appropriate culture system to restore human follicle dermal papilla cells (hFDPc) intrinsic properties; however, they show a low and variable efficiency to promote complete hair follicle formation in in vivo experiments. In this work, a conscientious analysis revealed a 25% cell viability in the surface of the dermal papilla spheroid (DPS) for all culture conditions, questioning whether it is an appropriate culture system for hFDPc. To overcome this problem, we propose the use of human blood plasma for the generation of fibrin microgels (FM) with encapsulated hFDPc to restore its inductive signature, either in the presence or in the absence of blood platelets. FM showed a morphology and extracellular matrix composition similar to the native dermal papilla, including Versican and Collagen IV and increasing cell viability up to 85%. While both systems induce epidermal invaginations expressing hair-specific keratins K14, K15, K71, and K75 in in vitro skin cultures, the number of generated structures increases from 17% to 49% when DPS and FM were used, respectively. These data show the potential of our experimental setting for in vitro hair follicle neogenesis with wild adult hFDPc using FM, being a crucial step in the pursuit of human hair follicle regeneration therapies.

Overcoming Paradoxical Kinase Priming by a Novel MNK1 Inhibitor.

Targeting the kinases MNK1 and MNK2 has emerged as a valuable strategy in oncology. However, most of the advanced inhibitors are acting in an adenosine triphosphate (ATP)-competitive mode, precluding the evaluation of different binding modes in preclinical settings. Using rational design, we identified and validated the 4,6-diaryl-pyrazolo[3,4-b]pyridin-3-amine scaffold as the core for MNK inhibitors. Signaling pathway analysis confirmed a direct effect of the hit compound EB1 on MNKs, and in line with the reported function of these kinases, EB1 only affects the growth of tumor but not normal cells. Molecular modeling revealed the binding of EB1 to the inactive conformation of MNK1 and the interaction with the specific DFD motif. This novel mode of action appears to be superior to the ATP-competitive inhibitors, which render the protein in a pseudo-active state. Overcoming this paradoxical activation of MNKs by EB1 represents therefore a promising starting point for the development of a novel generation of MNK inhibitors.

A Novel Saliva-Based miRNA Signature for Colorectal Cancer Diagnosis.

Salivary microRNAs (miRNAs) are of high interest as diagnostic biomarkers for non-oral cancer. However, little is known about their value for colorectal cancer (CRC) detection. Our study aims to characterize salivary miRNAs in order to identify non-invasive markers for CRC diagnosis. The screening of 754 miRNAs was performed in saliva samples from 14 CRC and 10 healthy controls. The differential expressed miRNAs were validated by RT-qPCR in 51 CRC, 19 adenomas and 37 healthy controls. Receiver operating characteristic (ROC) curves and logistic regression models were performed to analyze the clinical value of these miRNAs. Twenty-two salivary miRNAs were significantly deregulated in CRC patients vs. healthy individuals (P < 0.05) in the discovery phase. From those, five upregulated miRNAs (miR-186-5p, miR-29a-3p, miR-29c-3p, miR-766-3p, and miR-491-5p) were confirmed to be significantly higher in the CRC vs. healthy group (P < 0.05). This five-miRNA signature showed diagnostic value (72% sensitivity, 66.67% specificity, AUC = 0.754) to detect CRC, which was even higher in combination with carcinoembryonic antigen (CEA) levels. Overall, after the first global characterization of salivary miRNAs in CRC, a five-miRNA panel was identified as a promising tool to diagnose this malignancy, representing a novel approach to detect cancer-associated epigenetic alterations using a non-invasive strategy.

MicroRNA-654-5p suppresses ovarian cancer development impacting on MYC, WNT and AKT pathways.

Ovarian cancer is the most lethal gynecological malignancy due to the silent nature on its early onset and the rapid acquisition of drug resistance. Histologically heterogeneous, it includes several subtypes with different mutational landscapes, hampering the development of effective targeted therapies. Non-coding RNAs are emerging as potential new therapeutic targets in cancer. To search for a microRNA signature related to ovarian carcinomas and study its potential as effective targeted therapy, we examined the expression of 768 miRNA in a large collection of tumor samples and found miR-654-5p to be infraexpressed in ovarian serous carcinomas, the most common and aggressive type. Restoration of miR-654-5p levels reduced tumor cell viability in vitro and in vivo and impaired sphere formation capacity and viability of ovarian cancer patient-derived ascitic cells ex vivo. CDCP1 and PLAGL2 oncogenes were found to be the most relevant direct miR-654-5p targets and both genes convey in a molecular signature associated with key cancer pathways relevant to ovarian tumorigenesis, such as MYC, WNT and AKT pathways. Together, we unveiled the tumor suppressor function of miR-654-5p, suggesting that its restoration or co-targeting of CDCP1 and PLAGL2 may be an effective therapeutic approach for ovarian cancer.