Assessment of In Vitro Release Testing Methods for Colloidal Drug Carriers: The Lack of Standardized Protocols.

Although colloidal carriers have been in the pipeline for nearly four decades, standardized methods for testing their drug-release properties remain to be established in pharmacopeias. The in vitro assessment of drug release from these colloidal carriers is one of the most important parameters in the development and quality control of drug-loaded nano- and microcarriers. This lack of standardized protocols occurs due to the difficulties encountered in separating the released drug from the encapsulated one. This review aims to compare the most frequent types of release testing methods (i.e., membrane diffusion techniques, sample and separate methods and in situ detection techniques) in terms of the advantages and disadvantages of each one and of the key parameters that influence drug release in each case.

An overview of in vitro 3D models of the blood-brain barrier as a tool to predict the in vivo permeability of nanomedicines.

The blood-brain barrier (BBB) prevents efficient drug delivery to the central nervous system. As a result, brain diseases remain one of the greatest unmet medical needs. Understanding the tridimensional structure of the BBB helps gain insight into the pathology of the BBB and contributes to the development of novel therapies for brain diseases. Therefore, 3D models with an ever-growing sophisticated complexity are being developed to closely mimic the human neurovascular unit. Among these 3D models, hydrogel-, spheroid- and organoid-based static BBB models have been developed, and so have microfluidic-based BBB-on-a-chip models. The different 3D preclinical models of the BBB, both in health and disease, are here reviewed, from their development to their application for permeability testing of nanomedicines across the BBB, discussing the advantages and disadvantages of each model. The validation with data from in vivo preclinical data is also discussed in those cases where provided.

The Chick Embryo Chorioallantoic Membrane Model: A Research Approach for Ex Vivo and In Vivo Experiments.

BACKGROUND: The chick chorioallantoic membrane (CAM) model has attracted a great deal of interest in pharmaceutical and biological research as an alternative or complimentary in vivo assay to animal models. Traditionally, CAM assay has been widely used to perform some toxicological studies, specifically to evaluate the skin, ocular and embryo toxicity of new drugs and formulations, and to perform angiogenesis studies. Due to the possibility to generate the tumors onto the CAM, this model has also become an excellent strategy to evaluate the metastatic potential of different tumours and to test the efficacy of novel anticancer therapies in vivo. Moreover, in the recent years, its use has considerably grown in other research areas, including the evaluation of new anti-infective agents, the development of biodistribution studies and in tissue engineering research. OBJECTIVE: This manuscript provides a critical overview of the use of CAM model in pharmaceutical and biological research, especially to test the toxicity of new drugs and formulations and the biodistribution and the efficacy of novel anticancer and antiinfective therapies, analyzing its advantages and disadvantages in comparison to animal models. CONCLUSION: The chick chorioallantoic membrane model shows a great utility in several research areas, such as cancer, toxicology, biodistribution studies and anti-infective therapies. In fact, it has become an intermediate stage between in vitro experiments and animal studies, and, in the case of toxicological studies (skin and ocular toxicity), it has even replaced the animal models.

Embolization therapy with microspheres for the treatment of liver cancer: State-of-the-art of clinical translation.

Embolization with microspheres is a therapeutic strategy based on the selective occlusion of the blood vessels feeding a tumor. This procedure is intraarterially performed in the clinical setting for the treatment of liver cancer. The practice has evolved over the last decade through the incorporation of drug loading ability, biodegradability and imageability with the subsequent added functionality for the physicians and improved clinical outcomes for the patients. This review highlights the evolution of the embolization systems developed through the analysis of the marketed embolic microspheres for the treatment of malignant hepatocellular carcinoma, namely the most predominant form of liver cancer. Embolic microspheres for the distinct modalities of embolization (i.e., bland embolization, chemoembolization and radioembolization) are here comprehensively compiled with emphasis on material characteristics and their impact on microsphere performance. Moreover, the future application of the embolics under clinical investigation is discussed along with the scientific and regulatory challenges ahead in the field. STATEMENT OF SIGNIFICANCE: Embolization therapy with microspheres is currently used in the clinical setting for the treatment of most liver cancer conditions. The progressive development of added functionalities on embolic microspheres (such as biodegradability, imageability or drug and radiopharmaceutical loading capability) provides further benefit to patients and widens the therapeutic armamentarium for physicians towards truly personalized therapies. Therefore, it is important to analyze the possibilities that advanced biomaterials offer in the field from a clinical translational perspective to outline the future trends in therapeutic embolization.

DoE-based development of celecoxib loaded PLGA nanoparticles: In ovo assessment of its antiangiogenic effect.

Abnormal angiogenesis plays a main role in the pathogenesis of many diseases such as cancer, and inflammatory autoimmune disorders among others, and its inhibition represents a potential strategy for their management. Celecoxib (CXB) that is one of the most prescribed selective COX-2 inhibitors and is currently approved for the treatment of osteoarthritis, rheumatoid arthritis, and ankylosing spondylitis inhibits angiogenesis. The objective of this manuscript was to design, develop, and characterize polymeric nanoparticles for the parenteral administration of CXB which the aim of facilitating its administration and improving its antiangiogenic activity while decreasing its adverse effects. A Plackett-Burman design was used to optimize the formulation. The PVA concentration, the sonication time, the sonicator amplitude and the CXB:PLGA ratio were selected as independent variables and particle size, polydispersity index, drug loading, and entrapment efficiency as responses. Optimized nanoparticles (formulations F2, F6 and F9) showed a particle size around 280 nm, a low polydispersion (PDI ≤ 0.2), a negative zeta potential around -25 mV, a high entrapment efficiency (above 88 %) and a controlled drug release for at least 10 days. Moreover, they were physically and chemically stable for at least 3 months when stored at 4 °C. Interestingly, CXB-loaded nanoparticles showed a higher angiogenesis inhibition than CXB in solution administered at the same concentration. F9 nanoparticles that were prepared using PVA at 0.5 %, a sonication time of 7 min, a sonicator amplitude of 80 % and a CXB:PLGA ratio of 20:100 were selected as the most suitable CXB-formulation. It represents a promising strategy to administer CXB and improve its efficacy in disorders with pathological angiogenesis such as cancer and arthritic diseases.

Antibody-Antineoplastic Conjugates in Gynecological Malignancies: Current Status and Future Perspectives.

In the last decade, antibody-drug conjugates (ADCs), normally formed by a humanized antibody and a small drug via a chemical cleavable or non-cleavable linker, have emerged as a potential treatment strategy in cancer disease. They allow to get a selective delivery of the chemotherapeutic agents at the tumor level, and, consequently, to improve the antitumor efficacy and, especially to decrease chemotherapy-related toxicity. Currently, nine antibody-drug conjugate-based formulations have been already approved and more than 80 are under clinical trials for the treatment of several tumors, especially breast cancer, lymphomas, and multiple myeloma. To date, no ADCs have been approved for the treatment of gynecological formulations, but many formulations have been developed and have reached the clinical stage, especially for the treatment of ovarian cancer, an aggressive disease with a low five-year survival rate. This manuscript analyzes the ADCs formulations that are under clinical research in the treatment of gynecological carcinomas, specifically ovarian, endometrial, and cervical tumors.

Perspectives in Breast and Ovarian Cancer Chemotherapy by Nanomedicine Approach: Nanoformulations in Clinical Research.

BACKGROUND: Breast and ovarian carcinomas represent major health problems in women worldwide. Chemotherapy constitutes the main treatment strategy, and the use of nanocarriers, a good tool to improve it. Several nanoformulations have already been approved, and others are under clinical trials for the treatment of both types of cancers. OBJECTIVE: This review focuses on the analysis of the nanoformulations that are under clinical research in the treatment of these neoplasms. RESULTS: Currently, there are 6 nanoformulations in clinical trials for breast and ovarian carcinomas, most of them in phase II and phase III. In the case of breast cancer treatment, these nanomedicines contain paclitaxel; and, for ovarian cancer, nanoformulations containing paclitaxel or camptothecin analogs are being evaluated. The nanoencapsulation of these antineoplastics facilitates their administration and reduces their systemic toxicity. Nevertheless, the final approval and commercialization of nanoformulations may be limited by other aspects like lack of correlation between the efficacy results evaluated at in vitro and in vivo levels, difficulty in producing large batches of nanoformulations in a reproducible manner and high production costs compared to conventional formulations of antineoplastics. However, these challenges are not insurmountable and the number of approved nanoformulations for cancer therapy is growing. CONCLUSION: Reviewed nanoformulations have shown, in general, excellent results, demonstrating a good safety profile, a higher maximum tolerated dose and a similar or even slightly better antitumor efficacy compared to the administration of free drugs, reinforcing the use of nano-chemotherapy in both breast and ovarian tumors.

Active Targeted Nanoformulations via Folate Receptors: State of the Art and Future Perspectives.

In normal tissues, the expression of folate receptors is low and limited to cells that are important for embryonic development or for folate reabsorption. However, in several pathological conditions some cells, such as cancer cells and activated macrophages, overexpress folate receptors (FRs). This overexpression makes them a potential therapeutic target in the treatment of cancer and inflammatory diseases to obtain a selective delivery of drugs at altered cells level, and thus to improve the therapeutic efficacy and decrease the systemic toxicity of the pharmacological treatments. Two strategies have been used to achieve this folate receptor targeting: (i) the use of ligands with high affinity to FRs (e.g., folic acid or anti-FRs monoclonal antibodies) linked to the therapeutic agents or (ii) the use of nanocarriers whose surface is decorated with these ligands and in which the drug is encapsulated. This manuscript analyzes the use of FRs as a target to develop new therapeutic tools in the treatment of cancer and inflammatory diseases with an emphasis on the nanoformulations that have been developed for both therapeutic and imaging purposes.

Limitations and Challenges in the Stability of Cysteamine Eye Drop Compounded Formulations.

Accumulation of cystine crystals in the cornea of patients suffering from cystinosis is considered pathognomonic and can lead to severe ocular complications. Cysteamine eye drop compounded formulations, commonly prepared by hospital pharmacy services, are meant to diminish the build-up of corneal cystine crystals. The objective of this work was to analyze whether the shelf life proposed for six formulations prepared following different protocols used in hospital pharmacies is adequate to guarantee the quality and efficacy of cysteamine eye drops. The long-term and in-use stabilities of these preparations were studied using different parameters: content of cysteamine and its main degradation product cystamine; appearance, color and odor; pH and viscosity; and microbiological analysis. The results obtained show that degradation of cysteamine was between 20% and 50% after one month of storage in the long-term stability study and between 35% and 60% in the in-use study. These data confirm that cysteamine is a very unstable molecule in aqueous solution, the presence of oxygen being the main degradation factor. Saturation with nitrogen gas of the solutions offers a means of reducing cysteamine degradation. Overall, all the formulae studied presented high instability at the end of their shelf life, suggesting that their clinical efficacy might be dramatically compromised.

Timeline of Translational Formulation Technologies for Cancer Therapy: Successes, Failures, and Lessons Learned Therefrom.

Over the past few decades, the field of cancer therapy has seen a significant change in the way in which formulations are designed and developed, resulting in more efficient products that allow us to ultimately achieve improved drug bioavailability, efficacy, and safety. However, although many formulations have entered the market, many others have fallen by the wayside leaving the scientific community with several lessons to learn. The successes (and failures) achieved with formulations that have been approved in Europe and/or by the FDA for the three major types of cancer therapy (peptide-based therapy, chemotherapy, and radiotherapy) are reviewed herein, covering the period from the approval of the first prolonged-release system for hormonal therapy to the appearance of the first biodegradable microspheres intended for chemoembolization in 2020. In addition, those products that have entered phase III clinical trials that have been active over the last five years are summarized in order to outline future research trends and possibilities that lie ahead to develop clinically translatable formulations for cancer treatment.

PLGA Nanoparticles for the Intraperitoneal Administration of CBD in the Treatment of Ovarian Cancer: In Vitro and In Ovo Assessment.

The intraperitoneal administration of chemotherapeutics has emerged as a potential route in ovarian cancer treatment. Nanoparticles as carriers for these agents could be interesting by increasing the retention of chemotherapeutics within the peritoneal cavity. Moreover, nanoparticles could be internalised by cancer cells and let the drug release near the biological target, which could increase the anticancer efficacy. Cannabidiol (CBD), the main nonpsychotropic cannabinoid, appears as a potential anticancer drug. The aim of this work was to develop polymer nanoparticles as CBD carriers capable of being internalised by ovarian cancer cells. The drug-loaded nanoparticles (CBD-NPs) exhibited a spherical shape, a particle size around 240 nm and a negative zeta potential (-16.6 ± 1.2 mV). The encapsulation efficiency was high, with values above 95%. A controlled CBD release for 96 h was achieved. Nanoparticle internalisation in SKOV-3 epithelial ovarian cancer cells mainly occurred between 2 and 4 h of incubation. CBD antiproliferative activity in ovarian cancer cells was preserved after encapsulation. In fact, CBD-NPs showed a lower IC50 values than CBD in solution. Both CBD in solution and CBD-NPs induced the expression of PARP, indicating the onset of apoptosis. In SKOV-3-derived tumours formed in the chick embryo model, a slightly higher-although not statistically significant-tumour growth inhibition was observed with CBD-NPs compared to CBD in solution. To sum up, poly-lactic-co-glycolic acid (PLGA) nanoparticles could be a good strategy to deliver CBD intraperitoneally for ovarian cancer treatment.

Insights into the effects of the endocannabinoid system in cancer: a review.

In the last few decades, the endocannabinoid system has attracted a great deal of interest in terms of its applications to clinical medicine. In particular, its applications in cancer probably represent one of the therapeutic areas with most promise. On the one hand, expression of the endocannabinoid system is altered in numerous types of tumours, compared to healthy tissue, and this aberrant expression has been related to cancer prognosis and disease outcome, suggesting a role of this system in tumour growth and progression that depends on cancer type. On the other hand, cannabinoids exert an anticancer activity by inhibiting the proliferation, migration and/or invasion of cancer cells and also tumour angiogenesis. However, some cannabinoids, at lower concentrations, may increase tumour proliferation, inducing cancer growth. Enough data has been provided to consider the endocannabinoid system as a new therapeutic target in cancer, although further studies to fully establish the effect of cannabinoids on tumour progression are still needed.

Sistemas de liberación prolongada de opioides: Analgesia y dependencia / Extended-release delivery systems of opioids: Analgesia and dependence

El consumo de analgésicos opioides ha experimentado un vertiginoso ascenso en las últimas décadas a nivel mundial. Este elevado consumo está relacionado con el aumento del número de prescripciones de opioides para el tratamiento del dolor crónico y por el aumento de la dependencia a opioides. Los analgésicos opioides tienen una corta duración de acción, siendo necesarias múltiples administraciones para obtener analgesia prolongada. El empleo de formulaciones de liberación prolongada permite espaciar los intervalos posológicos y estabilizar las concentraciones máximas de fármaco en sangre, favoreciendo el cumplimiento terapéutico y reduciendo el riesgo de desarrollar adicción. Sin embargo, estas formulaciones llevan dosis más altas de analgésicos opioides que las hacen más susceptibles de ser alteradas. Así, los avances en tecnología farmacéutica más recientes se han orientado hacia la aplicación de recursos tecnológicos disuasorios de su utilización por vías de administración alternativas con fines no terapéuticos. A su vez, los sistemas de liberación modificada también juegan un papel esencial en el tratamiento de la adicción a opioides: con el desarrollo de sistemas de administración parenteral capaces de prolongar la liberación de opioides durante meses se consigue superar una de las mayores dificultades para alcanzar el éxito del tratamiento en este tipo de pacientes como es el cumplimiento terapéutico. En este artículo se realiza una revisión bibliográfica de los diferentes sistemas de liberación prolongada de opioides que se encuentran actualmente autorizados en Europa y/o en Estados Unidos para el tratamiento del dolor y de la dependencia a opioides. (AU)

The consumption of opioid analgesics has increased drastically in the last decades worldwide. This high consumption is linked with a surge in the number of opioid prescriptions for the treatment of chronic pain and a surge in opioid misuse and addiction. Opioid analgesics have a short duration of action, making necessary frequent administrations to provide extended analgesia. The use of prolonged-release formulations enables dosing intervals to be spaced out and drug blood levels to be stabilized, improving therapeutic compliance, and reducing the likelihood of developing addiction. However, these formulations contain higher doses of opioid analgesics which make them more susceptible to be manipulated. Hence, the most recent advances in pharmaceutical technology have been oriented towards the application of abuse deterrent technologies aiming to prevent their administration through alternative routes. Moreover, prolonged- release systems also play an essential role in the treatment of opioid addictions with the development of parenteral dosage forms capable of prolonging opioid release for months that help overcome one of the most important drawbacks in achieving treatment success, namely, patient compliance. We review herein the different prolonged-release opioid dosage forms currently approved in Europe and/or the United States for the treatment of pain and opioid dependence. (AU)

In vitro screening of nanomedicines through the blood brain barrier: A critical review.

The blood-brain barrier accounts for the high attrition rate of the treatments of most brain disorders, which therefore remain one of the greatest health-care challenges of the twenty first century. Against this background of hindrance to brain delivery, nanomedicine takes advantage of the assembly at the nanoscale of available biomaterials to provide a delivery platform with potential to raising brain levels of either imaging or therapeutic agents. Nevertheless, to prevent later failure due to ineffective drug levels at the target site, researchers have been endeavoring to develop a battery of in vitro screening procedures that can predict earlier in the drug discovery process the ability of these cutting-edge drug delivery platforms to cross the blood-brain barrier for biomedical purposes. This review provides an in-depth analysis of the currently available in vitro blood-brain barrier models (both cell-based and non-cell-based) with the focus on their suitability for understanding the biological brain distribution of forthcoming nanomedicines. The relationship between experimental factors and underlying physiological assumptions that would ultimately lead to a more predictive capacity of their in vivo performance, and those methods already assayed for the evaluation of the brain distribution of nanomedicines are comprehensively discussed.

Sistemas de liberación prolongada de opioides: Analgesia y dependencia / Extended-release delivery systems of opioids: Analgesia and dependence

El consumo de analgésicos opioides ha experimentado un vertiginoso ascenso en las últimas décadas a nivel mundial. Este elevado consumo está relacionado con el aumento del número de prescripciones de opioides para el tratamiento del dolor crónico y por el aumento de la dependencia a opioides. Los analgésicos opioides tienen una corta duración de acción, siendo necesarias múltiples administraciones para obtener analgesia prolongada. El empleo de formulaciones de liberación prolongada permite espaciar los intervalos posológicos y estabilizar las concentraciones máximas de fármaco en sangre, favoreciendo el cumplimiento terapéutico y reduciendo el riesgo de desarrollar adicción. Sin embargo, estas formulaciones llevan dosis más altas de analgésicos opioides que las hacen más susceptibles de ser alteradas. Así, los avances en tecnología farmacéutica más recientes se han orientado hacia la aplicación de recursos tecnológicos disuasorios de su utilización por vías de administración alternativas con fines no terapéuticos. A su vez, los sistemas de liberación modificada también juegan un papel esencial en el tratamiento de la adicción a opioides: con el desarrollo de sistemas de administración parenteral capaces de prolongar la liberación de opioides durante meses se consigue superar una de las mayores dificultades para alcanzar el éxito del tratamiento en este tipo de pacientes como es el cumplimiento terapéutico. En este artículo se realiza una revisión bibliográfica de los diferentes sistemas de liberación prolongada de opioides que se encuentran actualmente autorizados en Europa y/o en Estados Unidos para el tratamiento del dolor y de la dependencia a opioides

The consumption of opioid analgesics has increased drastically in the last decades worldwide. This high consumption is linked with a surge in the number of opioid prescriptions for the treatment of chronic pain and a surge in opioid misuse and addiction. Opioid analgesics have a short duration of action, making necessary frequent administrations to provide extended analgesia. The use of prolonged-release formulations enables dosing intervals to be spaced out and drug blood levels to be stabilized, improving therapeutic compliance, and reducing the likelihood of developing addiction. However, these formulations contain higher doses of opioid analgesics which make them more susceptible to be manipulated. Hence, the most recent advances in pharmaceutical technology have been oriented towards the application of abuse deterrent technologies aiming to prevent their administration through alternative routes. Moreover, prolonged- release systems also play an essential role in the treatment of opioid addictions with the development of parenteral dosage forms capable of prolonging opioid release for months that help overcome one of the most important drawbacks in achieving treatment success, namely, patient compliance. We review herein the different prolonged-release opioid dosage forms currently approved in Europe and/or the United States for the treatment of pain and opioid dependence

Validation protocol of analytical procedures for quantification of drugs in polymeric systems for parenteral administration: dexamethasone phosphate disodium microparticles.

In this work a protocol to validate analytical procedures for the quantification of drug substances formulated in polymeric systems that comprise both drug entrapped into the polymeric matrix (assay:content test) and drug released from the systems (assay:dissolution test) is developed. This protocol is applied to the validation two isocratic HPLC analytical procedures for the analysis of dexamethasone phosphate disodium microparticles for parenteral administration. Preparation of authentic samples and artificially "spiked" and "unspiked" samples is described. Specificity (ability to quantify dexamethasone phosphate disodium in presence of constituents of the dissolution medium and other microparticle constituents), linearity, accuracy and precision are evaluated, in the range from 10 to 50 µg mL(-1) in the assay:content test procedure and from 0.25 to 10 µg mL(-1) in the assay:dissolution test procedure. The robustness of the analytical method to extract drug from microparticles is also assessed. The validation protocol developed allows us to conclude that both analytical methods are suitable for their intended purpose, but the lack of proportionality of the assay:dissolution analytical method should be taken into account. The validation protocol designed in this work could be applied to the validation of any analytical procedure for the quantification of drugs formulated in controlled release polymeric microparticles.

Enmascaramiento de sabores en formas farmacéuticas sólidas orales / Taste masking in oral solid dosage forms

Aunque tradicionalmente ligado a formas farmacéuticas líquidas orales, el enmascaramiento del sabor como parámetro crítico en la formulación de medicamentos ha cobrado recientemente un nuevo auge en respuesta al desarrollo de formas farmacéuticas sólidas orales que persiguen una disgregación, bien ex vivo, bien en la cavidad bucal. El enmascaramiento no sólo comprende la neutralización del potencial sabor desagradable inherente al principio activo, sino también la obtención de un sabor agradable en la formulación final, con repercusión tanto a nivel sanitario, puesto que cuanto mayor sea la aceptación por parte del paciente, mayor será su adherencia al tratamiento; como a nivel económico, ya que el sabor del producto puede marcar la diferencia entre el éxito y el fracaso comercial. Mediante esta revisión se ponen de relieve las estrategias aplicables en el enmascaramiento de sabores de formas farmacéuticas sólidas orales, se clasifican y describen los principales excipientes correctores del sabor, así como se efectúa una compilación exhaustiva de las técnicas de evaluación de la eficacia de los distintos recursos empleados en el enmascaramiento del sabor desagradable. De esta forma, se amplía el ámbito de aplicación del concepto enmascaramiento del sabor, demostrándose que es un área del cual aún hay mucho por decir

Despite being traditionally associated with oral liquid dosage forms, taste masking as critical attribute in the formulation of drug products has recently experienced a renaissance, mostly due to the development of oral solid dosage forms aimed at achieving disintegration either under ex vivo conditions or even more relevantly into the oral cavity. Not only does taste masking involve the neutralization of the potential unpleasant flavour inherent to the drug substance, but also seeks to achieve tasty flavour in the final drug product, since it has influence both to a sanitary extent (the higher the patient acceptance, the better the patient compliance) and to an economical extent (since the flavour of a marketed product can make the difference between commercial success or commercial failure). The purpose of this review is to outline the strategies likely to be applied in taste masking of oral solid dosage forms, to sort out and describe the major flavour-modifying agents in the pharmaceutical field, as well as to compile comprehensively testing techniques of the efficacy of the various taste masking strategies. Consequently, this review adds to the scope of taste masking a further dimension, serving thus as a proof-of-concept that much remains still to be said in this area

Nuevas estrategias en terapia antitumoral basadas en la inducción de la apoptosis / New strategies in antitumor therapies based on apoptosis induction

Según la OMS para el año 2030 se producirán un total de 11,5 millones de defunciones por cáncer. Una alta proporción de estos tumores serán resistentes a los agentes antineoplásicos actuales, por ello, en los últimos años se ha realizado una intensa labor investigadora en la búsqueda de nuevas dianas para el tratamiento de tumores. Una de las dianas que está ofreciendo más posibilidades es el mecanismo de la apoptosis. La apoptosis se produce en condiciones fisiológicas como un mecanismo regulador del crecimiento de tejidos, en equilibrio con la proliferación celular. Su desregulación podría ayudar a explicar la patogénesis de algunos tumores malignos (AU)

According to OMS, in 2030 will be a total of 11.5 million deaths by cancer. A high proportion of these tumors will be resistant to current anticancer agents, and therefore, in the last years an intense investigation has been done to search new targets for antitumor treatment. One of the most interesting targets is the apoptosis mechanism. Apoptosis is produced in physiological conditions as a growth tissue regulator mechanism, in equilibrium with cellular proliferation. Its deregulation could explain the pathogenesis of some malignant tumors (AU)