Cysteine proteases as potential targets for anti-trypanosomatid drug discovery.

Leishmaniasis and trypanosomiasis are endemic neglected disease in South America and Africa and considered a significant public health problem, mainly in poor communities. The limitations of the current available therapeutic options, including the lack of specificity, relatively high toxicity, and the drug resistance acquiring, drive the constant search for new targets and therapeutic options. Advances in knowledge of parasite biology have revealed essential enzymes involved in the replication, survival, and pathogenicity of Leishmania and Trypanosoma species.

Cytosolic Ca measurements by ratiometric fluorescence microscopy in melanoma cells.

Cytosolic Ca levels are maintained at low nanomolar concentrations, and disruption of Ca homeostasis is associated with cell/tissue damage. Thus, methods have been developed to accurately assess cellular Ca levels, each with intrinsic advantages and disadvantages. Here, we present in detail a ratiometric fluorometric method for cytosolic Ca measurement in cultured melanoma cells using Fura 2-AM cell loading and fluorescence microscopy imaging.

Therapeutic potential of targeting mitochondrial dynamics in cancer.

In the past mitochondria were considered as the "powerhouse" of cell, since they generate more than 90% of ATP in aerobic conditions through the oxidative phosphorylation. However, based on the current knowledge, mitochondria play several other cellular functions, including participation in calcium homeostasis, generation of free radicals and oxidative species, triggering/regulation of apoptosis, among others. Additionally, previous discoveries recognized mitochondria as highly dynamic structures, which undergo morphological alterations resulting in long or short fragments inside the living cells.

BRAF and NRAS mutated melanoma: Different Ca responses, Na/Ca exchanger expression, and sensitivity to inhibitors.

Calcium is a ubiquitous intracellular second messenger, playing central roles in the regulation of several biological processes. Alterations in Ca homeostasis and signaling are an important feature of tumor cells to acquire proliferative and survival advantages, which include structural and functional changes in storage capacity, channels, and pumps. Here, we investigated the differences in Ca homeostasis in vemurafenib-responsive and non-responsive melanoma cells.

Targeting mitochondria in melanoma: Interplay between MAPK signaling pathway and mitochondrial dynamics.

Melanoma is a malignant proliferative disease originated in melanocytes, characterized by high metastatic activity and by the activation of oncogenes, such as B-RAF (40-60% of cases). Recent studies have shown that vemurafenib (a MAPK inhibitor) promoted disturbance of mitochondrial bioenergetics, although underlying mechanisms are not fully comprehended. Here we showed that MAPK inhibition by vemurafenib in B-RAF-mutated human melanoma culminated in the inhibition of DRP1 phosphorylation, associated to a large mitochondrial network remodeling to the hyperfused phenotype, and increased oxidative phosphorylation capacity.