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Biology subjects

Boyano, M. D.

Publications and source records attributed to Boyano, M. D..

3 recordsLinked to original sources

A new clinical tool to predict outcome in early-stage melanoma patients

Around 25% of early-stage melanoma patients eventually develop metastasis. Thus, we set out to define serological biomarkers that could be used along with clinical and histopathological features of the disease to predict these events. We previously demonstrated that in stage II melanoma patients, serum levels of dermcidin (DCD) were associated with metastatic progression. Based on the relevance of the immune response on the cancer progression and the recent association of DCD with local and systemic immune response against cancer cells, serum DCD was analyzed in a new cohort of patients along with IL-4, IL-6, IL-10, IL-17A, IFN{gamma} TGF{beta} and GM-CSF. We included 448 melanoma patients, 323 of whom were diagnosed as stages I-II according to AJCC. Levels of selected cytokines were determined by ELISA and Luminex and obtained data were analyzed employing Machine Learning and Kaplan-Meier techniques to define an algorithm capable of accurately classifying early-stage melanoma patients with a high and low risk of developing metastasis. The results show that in early-stage melanoma patients, serum levels of the cytokines IL-4, GM-CSF and DCD together with the Breslow thickness are those that best predict melanoma metastasis. Moreover, resulting algorithm represents a new tool to discriminate subjects with good prognosis from those with high risk for a future metastasis. Novelty and ImpactWe have developed a prognostic equation that considers the serum IL-4, GM-CSF and DCD levels, along with the Breslow thickness to accurately classify melanoma outcome in patients. In this sense, a rigorous follow-up is recommended for early-stage melanoma patients with a high Breslow thickness, high serum IL-4 levels and low GM-CSF and DCD levels at the time of diagnosis, given the elevated risk for these patients to develop metastasis during follow-up.

pathology↗

Evidences of conditioned behavior in Amoeba proteus

Associative memory is the main type of learning wherein complex organisms endowed with evolved nervous systems respond efficiently to determined environmental stimuli. This fundamental cognitive property has been evidenced in different multicellular species, from cephalopods to Humans, but never in individual cells. Here, following Pavlovs experiments with dogs that founded the principles of classical conditioning, we have observed the development of an associative memory in Amoeba proteus, which corresponds to the emergence of a new systemic motility pattern. In our cellular version of this conditioning behavior, we have used a controlled direct current electric field as the conditioned stimulus and a specific chemotactic peptide as the non-conditioned stimulus. Our study allowed us to demonstrate that Amoeba proteus are capable of linking two independent past events, and the induced associative memory can be recorded for up to at least four hours. For the first time, it has been observed that a systemic response to a specific stimulus can be modified by learning in unicellular organisms. This finding opens up a new framework in the understanding of the mechanisms underlying the complex systemic behavior involved in the cellular migration and the adaptive capacity of cells to the external medium.

systems biology↗

Long-Term Memory In The Migration Movements Of Enucleated Amoeba proteus

How motile, free unicellular organisms maximize the rate at which they encounter resources and develop optimal search strategies remains largely unknown. In fact, cell foraging is a very complex activity in which unicellular organisms integrate a diversity of external cues and develop efficient systemic movements to localize nourishment. These foraging strategies are critical when cells face conditions of scarce resources or they dont possess information on where food is located. Here, in order to determine whether nuclear activity is directly involved in cell migration, we placed single, well-isolated, enucleated and non-enucleated starved Amoeba proteus on nutrient-free petri dishes, and we then analyzed their trajectories of movement using non-linear dynamic tools. We found that despite being enucleated, the systemic responses of the protoplasm exhibited typical biological behaviors, moving with apparent normality, creeping along the substrate, developing pseudopodia and gobbling up prey. Our quantitative studies show that both the non-enucleated and enucleated amoebas display a similar migration structure, characterized by super-diffusivity, non-trivial long-term correlations and move-step fluctuations with scale invariant properties. In conclusion, the nuclear activity does not seem to directly control the systemic cellular movements involved in locating sparse resources.

systems biology↗