We have investigated Amblyomin-X-treated horse melanomas to better understand its mode of action through transcriptome analysis and the in vivo model. Amblyomin-X is a Kunitz-type homologous protein that selectively leads to the death of tumor cells via ER stress and apoptosis, currently under investigation as a new drug candidate for cancer treatment. Melanomas are immunogenic tumors, and a better understanding of the immune responses is warranted. Equine melanomas are spontaneous and not so aggressive as human melanomas are, as this study shows that the in vivo treatment of encapsulated horse melanoma tumors led to a significant reduction in the tumor size or even the complete disappearance of the tumor mass through intratumoral injections of Amblyomin-X. Transcriptome analysis identified ER-and mitochondria-stress, modulation of the innate immune system, apoptosis, and possibly immunogenic cell death activation. Interactome analysis showed that Amblyomin-X potentially interacts with key elements found in transcriptomics. Taken together, Amblyomin-X modulated the tumor immune microenvironment in different ways, at least contributing to induce tumor cell death. Melanoma is a type of cancer arising from the malignant transformation of melanocytes, pigment producing-cells found predominantly in the basal layer of the epidermis and eyes. Cutaneous melanoma is the most aggressive and treatment-resistant form of skin cancer responsible for the vast majority of skin cancer-related deaths in the Caucasian population 1. The global incidence of melanoma continues to increase at an alarming rate, despite decades of public prevention programs in many countries. Around 232,000 new cases of skin cancer were recorded worldwide in 2012, accounting for 1.6% of all new cases of cancer back then, while over 300,000 new cases of melanoma were diagnosed worldwide in 2018, according to the World Cancer Research Foundation 2,3. In Brazil, 1,547 deaths were recorded in 2013 due to melanoma, with around 5,690 new cases reported back then, while around 6,260 new cases were expected due in 2018, according to the National Cancer Institute (INCA) 4. Cutaneous melanoma usually affects a higher proportion of patients, in the age range 40-60 years. They can be treated by surgical excision when detected in the early stage (0, I, II and resectable III), however, in the later stages (unresectable III, IV and recurrent melanoma) the treatment options are chemotherapy, target therapy (BRAF/ MEK pathway inhibitors), immunotherapy (checkpoint blockade CTLA-4 receptor inhibition, PD-1 ↔ PD-L1 axis inhibition, and interferon-gamma immunotherapy), or a combination of them. Death in most patients is caused by metastatic disease which may have evolved from the primary tumor. Therefore, there is a need for new

Fetal membranes are abundant, ethically acceptable and readily accessible sources of stem cells. In particular, the yolk sac is a source of cell lineages that do not express MHCs and are mainly free from immunological incompatibles when transferred to a recipient. Although data are available especially for hematopoietic stem cells in mice and human, whereas other cell types and species are dramatically underrepresented. Here we studied the nature and differentiation potential of yolk sac derived mesenchymal stem cells from a New World mouse, Necromys lasiurus. Explants from mid-gestation were cultured in DMEM-High glucose medium with 10% defined fetal bovine serum. The cells were characterized by standard methods including immunophenotyping by fluorescence and flow cytometry, growth and differentiation potential and tumorigenicity assays. The first adherent cells were observed after 7 days of cell culture and included small, elongated fibroblast-like cells (92.13%) and large, round epithelial-like cells with centrally located nuclei (6.5%). Only the fibroblast-like cells survived the first passages. They were positive to markers for mesenchymal stem cells (Stro-1, CD90, CD105, CD73) and pluripotency (Oct3/4, Nanog) as well as precursors of hematopoietic stem cells (CD117). In differentiation assays, they were classified as a multipotent lineage, because they differentiated into osteogenic, adipogenic, and chondrogenic lineages and, finally, they did not develop tumors. In conclusion, mesenchymal progenitor cells with multipotent differentiation potential and sufficient growth and proliferation abilities were able to be obtained from Necromys yolk sacs, therefore, we inferred that these cells may be promising for a wide range of applications in regenerative medicine.

IPL treatment significantly increased the number of collagen and elastic fibers within the dermis and improved the parallel distribution of collagen fibers in relation to the epidermis. These results were evident after three IPL treatments. Lasers Surg. Med. © 2018 Wiley Periodicals, Inc.

Graphical abstract