Constructal approach to cell membranes transport: Amending the 'Norton-Simon' hypothesis for cancer treatment

A Thermodynamic Perspective of Cancer Cells' Volume/Area Expansion Ratio

The constructal law is used to improve the analysis of the resonant heat transfer in cancer cells. The result highlights the fundamental role of the volume/area ratio and its role in cancer growth and invasion. Cancer cells seek to increase their surface area to facilitate heat dissipation; as such, the tumour expansion ratio declines as malignant cells start to migrate and the cancer expands locally and systemically. Consequently, we deduce that effective anticancer therapy should be based on the control of some ion transport phenomena in an effort to increase the volume/area ratio. This emphasises restricting the local and systemic spatial expansion of the tumour system and thus gives further credence to the superior role of novel anti-migratory and anti-invasive treatment strategies over conventional anti-proliferative options only.

Predicting cancer stages from tissue energy dissipation

Understanding cancer staging in order to predict its progression is vital to determine its severity and to plan the most appropriate therapies. This task has attracted interest from different fields of science and engineering. We propose a computational model that predicts the evolution of cancer in terms of the intimate structure of the tissue, considering that this is a self-organised structure that undergoes transformations governed by non-equilibrium thermodynamics laws. Based on experimental data on the dependence of tissue configurations on their elasticity and porosity, we relate the cancerous tissue stages with the energy dissipated, showing quantitatively that tissues in more advanced stages dissipate more energy. The knowledge of this energy allows us to know the probability of observing the tissue in its different stages and the probability of transition from one stage to another. We validate our results with experimental data and statistics from the World Health Organisation. Our quantitative approach provides insights into the evolution of cancer through its different stages, important as a starting point for new and integrative research to defeat cancer.

Numerical Investigation of a Thermal Ablation Porous Media-Based Model for Tumoral Tissue with Variable Porosity

Thermal ablation is a minimally or noninvasive cancer therapy technique that involves fewer complications, shorter hospital stays, and fewer costs. In this paper, a thermal-ablation bioheat model for cancer treatment is numerically investigated, using a porous media-based model. The main objective is to evaluate the effects of a variable blood volume fraction in the tumoral tissue (i.e., the porosity), in order to develop a more realistic model. A modified local thermal nonequilibrium model (LTNE) is implemented including the water content vaporization in the two phases separately and introducing the variable porosity in the domain, described by a quadratic function changing from the core to the rim of the tumoral sphere. The equations are numerically solved employing the finite-element commercial code COMSOL Multiphysics. Results are compared with the results obtained employing two uniform porosity values (ε = 0.07 and ε = 0.23) in terms of coagulation zones at the end of the heating period, maximum temperatures reached in the domain, and temperature fields and they are presented for different blood vessels. The outcomes highlight how important is to predict coagulation zones achieved in thermal ablation accurately. In this way, indeed, incomplete ablation, tumor recurrence, or healthy tissue necrosis can be avoided, and medical protocols and devices can be improved.

Magnetic field potential effects on the doxorubicin therapeutic activity in Ehrlich tumor growth

Aim

Therapeutic choices for cancer patients include many combinations of therapeutic protocols. The present study aimed to investigate and discuss the combined effects of magnetic field and chemotherapy treatment on Ehrlich tumor-induced growth in Swiss albino mice. The benefits of both treatments are discussed and interpreted.

Methods

Fifty adult male mice were randomly divided into two groups; ten mice in the first group served as control group and forty in the second group which received a single dose IP injection of tumor fluid (0.02 Ml) to induce tumor. Ten days post injection to allow the tumor to growth, the 40 mice were sub- divided in to 4 sub-groups 10 mice pre each to introduce the treatment.

Results

The results indicated tumor growth inhibition regarding mean tumor volume variation (ml) presented. All treatments display tumor growth prevention effect compared to control untreated mice. Treatment with Dox + 7G (MF) exposure exhibited a significant inhibition of tumor growth than that treated alone with DOX or magnetic field; 82% inhibition for DOX + MF 7 G against 60% for 7 G , and 31% for DOX only. Optical density data show a higher values of the molar absorption coefficient ε for all treated groups than untreated one. The fluorescence emission spectra of Hb show an emission peaks λem at 465, 515, and 639 nm. Hematological examination might indicate to discriminative effects to RBCs, WBCs or/and Hb for all treated groups. Moreover, treatment with Dox + 7G MF shows a proper discriminative effects than that treatment with DOX or magnetic field only. Osmotic fragility (OF) test indicates that the combination between drug and magnetic field have nontoxic effect against RBCs membrane.

Conclusion

Our findings support further exploration of the potential of magnetic fields in cancer therapeutics, either as adjunct or primary therapy. It may be due to enhancing the drug interaction with tumor cells which increase the therapeutic index of DOX and resulted in increased anti-tumor activity against Ehrlich tumor models. These benefits promote the use of the magnetic field in cancer with chemotherapy over the other traditional treatment agents this highly adapted manner can be used in improving the clinical treatment protocol and fights against cancer.

Non-Equilibrium Thermodynamic Approach to Ca2+-Fluxes in Cancer

Living systems waste heat in their environment. This is the measurable effect of the irreversibility of the biophysical and biochemical processes fundamental to their life. Non-equilibrium thermodynamics allows us to analyse the ion fluxes through the cell membrane, and to relate them to the membrane electric potential, in order to link this to the biochemical and biophysical behaviour of the living cells. This is particularly interesting in relation to cancer, because it could represent a new viewpoint, in order to develop new possible anticancer therapies, based on the thermoelectric behaviour of cancer itself. Here, we use a new approach, recently introduced in thermodynamics, in order to develop the analysis of the ion fluxes, and to point out consequences related to the membrane electric potential, from a thermodynamic viewpoint. We show how any increase in the cell temperature could generate a decrease in the membrane electric potential, with a direct relation between cancer and inflammation. Moreover, a thermal threshold, for the cell membrane electric potential gradient, has been obtained, and related to the mitotic activity. Finally, we obtained the external surface growth of the cancer results related (i) to the Ca2+-fluxes, (ii) to the temperature difference between the the system and its environment, and (iii) to the chemical potential of the ion species.

The importance of ion fluxes for cancer proliferation and metastasis: A thermodynamic analysis

Following a thermodynamic approach, we develop a new theoretical analysis of ion transfer across cell membranes. Supported also by experimental data from the literature, we highlight that ion channels determine the typical features of cancer cells, i.e. independence from growth-regulatory signals, avoidance of apoptosis, indefinite proliferative potential, and the capability of inducing angiogenesis. Specifically, we analyse how ion transport, with particular regards to Ca²⁺ fluxes, modulates cancer cell proliferation, and regulates cell cycle checkpoints. Finally, our analysis also suggests that in malignant tumours aerobic glycolysis is the more efficient metabolic process when taking the required solvent capacity into account.

Parameters Estimation in Phase-Space Landscape Reconstruction of Cell Fate: A Systems Biology Approach

The thermodynamical formalism of irreversible processes offers a theoretical framework appropriate to explain the complexity observed at the macroscopic level of dynamic systems. In this context, together with the theory of complex systems and systems biology, the thermodynamical formalism establishes an appropriate conceptual framework to address the study of biological systems, in particular cancer.The Chapter is organized as follows: In Subheading 1, an integrative view of these disciplines is offered, for the characterization of the emergence and evolution of cancer, seen as a self-organized dynamic system far from the thermodynamic equilibrium. Development of a thermodynamic framework, based on the entropy production rate, is presented in Subheading 2. Subheading 3 is dedicated to all tumor growth, as seen through a "phase transitions" far from equilibrium. Subheading 4 is devoted to complexity of cancer glycolysis. Finally, some concluding remarks are presented in Subheading 5.

Rate of entropy model for irreversible processes in living systems

In living systems, it is crucial to study the exchange of entropy that plays a fundamental role in the understanding of irreversible chemical reactions. However, there are not yet works able to describe in a systematic way the rate of entropy production associated to irreversible processes. Hence, here we develop a theoretical model to compute the rate of entropy in the minimum living system. In particular, we apply the model to the most interesting and relevant case of metabolic network, the glucose catabolism in normal and cancer cells. We show, (i) the rate of internal entropy is mainly due to irreversible chemical reactions, and (ii) the rate of external entropy is mostly correlated to the heat flow towards the intercellular environment. The future applications of our model could be of fundamental importance for a more complete understanding of self-renewal and physiopatologic processes and could potentially be a support for cancer detection.