Development and in vivo evaluation of fused benzazole analogs of anti-melanoma agent HA15.

Background: In line with our recent discovery of an efficient anticancer thiazolebenzenesulfonamide framework HA15 (1) based on a remarkable endoplasmic reticulum stress inducement mode of action, we report herein a series of innovative constrained HA15 analogs, featuring four types of bicylic derivatives. Results: The structure-activity relationship analysis, using a cell line assay, led us to identify a novel version of HA15: a new benzothiazole derivative (10b) exhibiting important anti-melanoma effect against sensitive and resistant melanoma cells. Meanwhile, compound 10b induced a significant tumor growth inhibition in vivo with no apparent signs of toxicity. Conclusion: These results consistently open new directions to improve and develop more powerful anticancer therapeutics harboring this type of fused framework.

Discovery of a new molecule inducing melanoma cell death: dual AMPK/MELK targeting for novel melanoma therapies.

In the search of biguanide-derived molecules against melanoma, we have discovered and developed a series of bioactive products and identified the promising new compound CRO15. This molecule exerted anti-melanoma effects on cells lines and cells isolated from patients including the ones derived from tumors resistant to BRAF inhibitors. Moreover, CRO15 was able to decrease viability of cells lines from a broad range of cancer types. This compound acts by two distinct mechanisms. First by activating the AMPK pathway induced by a mitochondrial disorder. Second by inhibition of MELK kinase activity, which induces cell cycle arrest and activation of DNA damage repair pathways by p53 and REDD1 activation. All of these mechanisms activate autophagic and apoptotic processes resulting in melanoma cell death. The strong efficacy of CRO15 to reduce the growth of melanoma xenograft sensitive or resistant to BRAF inhibitors opens interesting perspective.

Innate lymphocyte-induced CXCR3B-mediated melanocyte apoptosis is a potential initiator of T-cell autoreactivity in vitiligo.

T-cells play a crucial role in progression of autoimmunity, including vitiligo, yet the initial steps triggering their activation and tissue damage remain unknown. Here we demonstrate increased presence of type-1 innate lymphoid cells (NK and ILC1)-producing interferon gamma (IFNγ) in the blood and in non-lesional skin of vitiligo patients. Melanocytes of vitiligo patients have strong basal expression of chemokine-receptor-3 (CXCR3) isoform B which is directly regulated by IFNγ. CXCR3B activation by CXCL10 at the surface of cultured human melanocytes induces their apoptosis. The remaining melanocytes, activated by the IFNγ production, express co-stimulatory markers which trigger T-cell proliferation and subsequent anti-melanocytic immunity. Inhibiting the CXCR3B activation prevents this apoptosis and the further activation of T cells. Our results emphasize the key role of CXCR3B in apoptosis of melanocytes and identify CXCR3B as a potential target to prevent and to treat vitiligo by acting at the early stages of melanocyte destruction.

Beside P53 and PTEN: Identification of molecular alterations of the RAS/MAPK and PI3K/AKT signaling pathways in high-grade serous ovarian carcinomas to determine potential novel therapeutic targets.

Despite great histological and molecular heterogeneity, the clinical management of high-grade ovarian carcinomas remains unspecialized. As a major subgroup, high-grade serous ovarian carcinomas (HGSOCs) require novel therapies. In addition to utilizing conventional histological prognostic markers and performing oncogenetic investigations, the molecular diagnostic method of next generation sequencing (NGS) was performed to identify 'druggable' targets that could provide access to innovative therapy. The present study was performed in 45 HGSOC patients (mean age, 59.1 years; range, 25-87 years) with histologically proven HGSOC. Breast cancer 1/2 (BRCA1/2) germline mutations were screened in 17 patients with a familial or personal history of cancer, which was justified by oncogenetic investigations. Tumor protein 53 (P53) and phosphatase and tensin homolog (PTEN) expression were assessed in formalin-fixed paraffin-embedded tissues using immunohistochemistry. Somatic mutations of Kirsten rat sarcoma viral oncogene homolog, neuroblastoma RAS viral oncogene homolog (NRAS), B-Raf proto-oncogene, serine/threonine kinase, phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α (PIK3CA) and MET proto-oncogene, receptor tyrosine kinase (MET) were screened using NGS on DNA extracts from frozen tumor specimens obtained at diagnosis. With a median follow-up of 38 months (range, 6-93 months), 20 patients are alive, 10 patients are disease-free and 14 patients progressed within 6 months following platinum-based therapy. P53 overexpression was detected in 67% of patients and PTEN loss was detected in 38% of the patients. The overexpression of mutant P53 was found to be associated with a longer progression-free and overall survival. In total, 2 NRAS (exon 3), 3 PIK3CA (exon 5 and 10) and 5 MET mutations (exons 14 and 18) were detected. In HGSOCs, in addition to P53 and PTEN alterations, somatic genetic abnormalities can be detected using NGS and provide molecular rationale for targeted therapies, potentially offering novel therapeutic opportunities to patients.

Discovery and Optimization of N-(4-(3-Aminophenyl)thiazol-2-yl)acetamide as a Novel Scaffold Active against Sensitive and Resistant Cancer Cells.

Cancer is the second cause of deaths worldwide and is forecasted to affect more that 22 million people in 2020. Despite dramatic improvement in its care over the last two decades, the treatment of resistant forms of cancer is still an unmet challenge. Thus, innovative and efficient treatments are still needed. In this context, we report herein the synthesis and the evaluation of a new class of bioactive molecules belonging to the N-(4-(3-aminophenyl(thiazol-2-yl)acetamide family. Structure-activity relationships could be driven and resulted in the discovery of lead compound 6b. The latter display high in vitro potency against both sensitive and resistant cancer cell lines on three models: melanoma, pancreatic cancer, and chronic myeloid leukemia (CML). 6b leads to cell death by concomitant induction of apoptosis and autophagy, shows good pharmacokinetic properties, and demonstrates a significant reduction of tumor growth in vivo on A375 xenograft model in mice.

Herpes zoster oticus: a clinical model for a transynaptic, reflex pathways, viral transmission hypotheses.

Reactivation of the varicella-zoster virus (VZV) along the sensory nerves innervating the ear, including the geniculate ganglion, is responsible for herpes zoster oticus (HZO). In some cases, HZO is associated with polyneuropathy of the cranial nerves, although the mechanism of this involvement is not known. To explain this phenomenon and based on some clinical considerations, the present authors hypothesize an intersynaptic spread of VZV along the reflex pathways of the brainstem.

The contribution of selective dysventilation to attical middle ear pathology.

Epitympanic primary cholesteatoma represents a challenge for ENT surgeons. Its exact pathogenesis is still unknown because of the very complex anatomy of this region. Until now, only a few authors have described this region and tried to hypothesize the causes that could lead to cholesteatoma genesis. We hypothesize the existence of a selective dysventilation of the epitympanic region based on the presence of various mucosal folds occluding air ventilation from the middle ear to the epitympanum, through the epitympanic isthmus, causing a negative epitympanic pressure and consequently cholesteatoma formation. All the anatomic findings were obtained with the aid of 0° and 45° angled surgical endoscopes. From our findings, patients affected by an epitympanic cholesteatoma often have a total isthmus blockage that completely isolates the whole epitympanum from the middle ear, causing a deficit of oxygenation of the mucosa that normally should be guaranteed by the Eustachian tube and which always works physiologically in these patients. This is confirmed by the tympanogram test where we observed how the pressure at the level of the tympanic cavity was normal, whereas the epitympanic pressure was selectively negative. In conclusion, selective epitympanic dysventilation syndrome consists of the concomitant presence of a series of complete or incomplete epitympanic diaphragms and ME isthmus blockage causing negative epitympanic pressure, and leading to the formation of a retraction pocket or cholesteatoma associated with normal Eustachian tube function.