Recalculating the Route: Repositioning Antimicrobial Peptides for Cancer Treatment.

Resistance to antimicrobial drugs has been considered a public health problem. Likewise, the increasing resistance of cancer cells to drugs currently used in therapy has also become a problem. Therefore, the research and development of synthetic peptides bring a new perspective on the emergence of new drugs for treating this resistance since bioinformatics provides a means to optimize these molecules and save time and costs in research. Peptides have several mechanisms of action, such as forming pores on the cell membrane and inhibiting protein synthesis. Some studies report the use of antimicrobial peptides with the potential for action against cancer cells, suggesting a repositioning of antimicrobial peptides to fight back cancer resistance. There is an alteration in the microenvironment, making its net charge negative for the survival and growth of cancer cells. The changes in glycoproteins favor the membrane to have a more negative charge, favoring the interaction between the cells and the peptide, thus making possible the repositioning of these antimicrobial peptides against cancer. Here, we will discuss the mechanism of action, targets and effects of peptides, comparison between microbial and cancer cells, and proteomic changes caused by the interaction of peptides and cells.

Leukemic Stem Cell: A Mini-Review on Clinical Perspectives.

Hematopoietic stem cells (HSCs) are known for their ability to proliferate and self-renew, thus being responsible for sustaining the hematopoietic system and residing in the bone marrow (BM). Leukemic stem cells (LSCs) are recognized by their stemness features such as drug resistance, self-renewal, and undifferentiated state. LSCs are also present in BM, being found in only 0.1%, approximately. This makes their identification and even their differentiation difficult since, despite the mutations, they are cells that still have many similarities with HSCs. Although the common characteristics, LSCs are heterogeneous cells and have different phenotypic characteristics, genetic mutations, and metabolic alterations. This whole set of alterations enables the cell to initiate the process of carcinogenesis, in addition to conferring drug resistance and providing relapses. The study of LSCs has been evolving and its application can help patients, where through its count as a biomarker, it can indicate a prognostic factor and reveal treatment results. The selection of a target to LSC therapy is fundamental. Ideally, the target chosen should be highly expressed by LSCs, highly selective, absence of expression on other cells, in particular HSC, and preferentially expressed by high numbers of patients. In view of the large number of similarities between LSCs and HSCs, it is not surprising that current treatment approaches are limited. In this mini review we seek to describe the immunophenotypic characteristics and mechanisms of resistance presented by LSCs, also approaching possible alternatives for the treatment of patients.

Male-to-Female Gender-Affirming Surgery Using Nile Tilapia Fish Skin as a Biocompatible Graft.

STUDY OBJECTIVE: Insufficient penile skin is common during vaginoplasty for male-to-female transition. This issue may be compensated by a scrotal skin flap, with the drawback of hair growth [1]. In recent studies, Nile tilapia skin was successfully used for the surgical management of Mayer-Rokitansky-Küster-Hauser syndrome [2,3] and vaginal stenosis [4,5]. This study aims to describe a novel technique for primary vaginoplasty in male-to-female gender-affirming surgery using Nile tilapia skin as a biocompatible graft to ensure adequate vaginal depth. DESIGN: Stepwise demonstration of the procedure with narrated video footage. SETTING: Transgender health clinic. INTERVENTIONS: A 29-year-old patient with gender dysphoria was referred to our office because of a desire for gender-affirming surgery. A physical examination revealed normal male genitalia with a 14-cm-long penis. Before surgery, approval from the institutional review board and written permission from the patient were obtained. After orchiectomy, penile disassembly, perineal dissection, and urethroplasty were performed, and a hollow Nile tilapia skin mold was prepared and sutured to the distal edge of the remaining penile skin. This structure was inverted, covering the newly created canal. The neocavity was then filled with a handmade inflatable vaginal mold, held in place by sutures in the labia majora. Finally, labiaplasty and clitoroplasty were conducted. After 7 days, the inflatable mold was removed, and the use of progressively larger dilators was initiated. After 3 weeks, a neovagina that was 16 cm long and able to accommodate the width of 2 fingers was detected. At that time, the Nile tilapia skin was completely reabsorbed into the neovaginal mucosa. There were no complications in the early postsurgical period. CONCLUSION: Nile tilapia skin, a safe, low-cost, and easy-to-use biocompatible material, may be an alternative option to scrotal skin grafts for neovaginal augmentation in primary vaginoplasty for male-to-female gender transition. However, further studies are needed to confirm this assertive.