Molecular regulatory pathways associated with posterior capsular opacification / 眼科新进展

Cataract surgery is one of the most common and mature eye surgeries in the world,and the procedures include the removal of turbid lens and intraocular lens (IOL) implantation,which can better restore the patient' s vision.Posterior capsular opacification (PCO),also known as secondary cataract,is one of the most coramon complications after cataract surgery,seriously affecting the surgical efficacy.Two to five years after cataract surgery,PCO-induced loss of vision accounted for 20％-40％ of patients.PCO is a fibrotic disease,and its mechanism has become an important medical topic.It has been demonstrated that the residual lens epithelial cells (LECs) in the equatorial and anterior capsule region after surgery have become fibroblasts and myofibroblasts via proliferation,migration and epithelial-mesenchymal transition (EMT) accompanied by extracellular matrix (ECM) synthesis,eventually leading to the occurrence of PCO.A series of growth factors and signaling pathways participate and play a key role in the initiation and development of PCO.In this review,recent advances in molecular regulation pathways associated with PCO will be summarized,and the possible methods interfering with PCO will be explored.

Mesua ferrea stem bark extract induces apoptosis and inhibits metastasis in human colorectal carcinoma HCT 116 cells, through modulation of multiple cell signalling pathways / 中国天然药物

Considering the great potential of natural products as anticancer agents, the present study was designed to explore the molecular mechanisms responsible for anticancer activities of Mesua ferrea stem bark extract against human colorectal carcinoma. Based on MTT assay results, bioactive sub-fraction (SF-3) was selected for further studies using HCT 116 cells. Repeated column chromatography resulted in isolation of less active α-amyrin from SF-3, which was identified and characterized by GC-MS and HPLC methods. α-amyrin and betulinic acid contents of SF-3 were measured by HPLC methods. Fluorescent assays revealed characteristic apoptotic features, including cell shrinkage, nuclear condensation, and marked decrease in mitochondrial membrane potential in SF-3 treated cells. In addition, increased levels of caspases-9 and -3/7 levels were also observed in SF-3 treated cells. SF-3 showed promising antimetastatic properties in multiple in vitro assays. Multi-pathway analysis revealed significant down-regulation of WNT, HIF-1α, and EGFR with simultaneous up-regulation of p53, Myc/Max, and TGF-β signalling pathways in SF-3 treated cells. In addition, promising growth inhibitory effects were observed in SF-3 treated HCT 116 tumour spheroids, which give a hint about in vivo antitumor efficacy of SF-3 phytoconstituents. In conclusion, these results demonstrated that anticancer effects of SF-3 towards colon cancer are through modulation of multiple molecular pathways.

Nuevas terapias target y vías moleculares clínicamente relevantes en carcinoma hepatocelular avanzado / New targeted therapies and molecular routes clinically relevant in advanced hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common tumors worldwide. Most cases occur in patients with chronic liver disease who are diagnosed at an advanced stage, and their prognosis is poor. Because HCC is resistant to conventional systemic therapies, molecular therapies have emerged and been established as the standard for advanced forms of the disease. Since the publication of phase III clinical studies on sorafenib, research has searched for new molecular targets. Thus, multiple clinical studies that inhibit relevant molecular pathways have been performed with numerous patients. Many of these trials have had unexpectedly negative results, not only due to patient complexity and the difficulty in evaluating a therapeutic response, quality of life and the survival rate but also because phase II clinical studies, without the selection of molecular targets, have continued on to poor results in phase III studies. This review article aims to evaluate different phase II and phase III clinical studies to understand the clinically relevant molecular pathways and to improve the future management of HCC patients.

El carcinoma hepatocelular (CHC) es uno de los tumores más comunes a nivel mundial. La mayoría de los casos ocurre en pacientes con enfermedad hepática crónica, quienes son diagnosticados en un estado avanzado con muy pobre pronóstico. Terapias moleculares orientadas al tratamiento del CHC han sido destacadas; estas pueden afectar la proliferación celular del tumor, diferenciación celular, angiogénesis, invasión y metástasis, entre otros procesos críticos al desarrollo del tumor. El estándar para el CHC avanzado es la terapia target usando Sorafenib, sin embargo, nuevas moléculas han sido testeadas en estudios fase III de primera línea, tales como sunitinib, brivanib, erlotinib y linifanib, sin superioridad sobre sorafenib. La investigación de nuevos tratamientos es un desafío para investigadores, hepatólogos y oncólogos. Las principales vías moleculares de CHC con relevancia en estudios clínicos fase II y III son: MAP-kinase (MAPK), PI3K/AKT/mTOR, (HGF)/c-Met, cromatina y regulación epigenética, mantenimiento de telómeros, Notch, Hedgehog, Hippo y vía señalizante Jak/STAT. Las terapias futuras en CHC pueden ser orientadas rutinariamente usando sólo objetivos adecuados para terapias moleculares y seleccionando subgrupos de pacientes sobre la base de la expresión de targets moleculares o basados en nuevas clasificaciones definidas por estudios genómicos.

Review of stem cell deregulation and breast cancer: An emerging hypothesis.

Cancer is fundamentally a cellular genetic disease capable of transferring the "disease" to the next generation of mutated cells. Similar proliferative and information transferring capacity exists in the stem cells of various organ systems in the human body. Understanding the bio-mechanism of stem cell metabolism and its regulation by signaling molecules and extracellular micro-environment is an important step toward successful prevention and treatment of cancer. According to the cancer stem cell hypothesis, both hereditary and sporadic cancers can arise from deregulation of these cancer stem cells (CSCs), triggered by genetic and environmental factors. It is shown that deregulation of normal self-renewal pathways in undifferentiated breast stem cells or progenitor cells had altered mammary system or progenitor cells, resulting in abnormally differentiated cells in human and rodent breast cancer cell lines. Breakthroughs in molecular pathways have important therapeutic implications. Hence, significant stress is laid on targeting signaling molecules and their micromilieu in breast cancer therapy.

Plasticidade muscular no exercício físico / Plasticity in muscular exercise

O objetivo deste estudo foi elaborar uma revisão dos principais mecanismos celulares e moleculares envolvidos no processo de hipertrofia e modulação fenotípica do músculo esquelético, em resposta ao exercício/treinamento físico. Inicialmente, apresentamos uma visão geral do músculo esquelético, com ênfase nas características gerais das fibras musculares e na plasticidade muscular. Em seguida, descrevemos a morfologia e a participação dos mionúcleos e das células satélites durante a hipertrofia muscular, e também, a atuação dos fatores de crescimento sobre a atividade das células satélites. Finalmente, apontamos as principais vias moleculares que mediam as alterações na expressão de proteínas músculo-específicas, de acordo com a especificidade das respostas funcionais ao exercício/treinamento físico.

The aim of this study was prepare a review of the majors cellular and molecular mechanisms involved in hypertrophy and phenotypic modulation of skeletal muscle in response to exercise/physical training. Initially, we present an overview of skeletal muscle, with emphasis on the general characteristics of the muscle fibers and muscle plasticity. Then, we describe the morphology and participation of myonuclei and satellite cells during muscle hypertrophy, and also the action of growth factors on the activity of cells satellites. Finally, we showed the key molecular pathways that mediate changes in the expression of muscle-specific proteins, according to the specificity of functional responses to the exercise/physical training.

Entendiendo las causas de la obesidad a traves de la biologia celular del adiposito

La obesidad es un área multidisciplinaria, cuya biología abarca: 1) los mecanismos fundamentales sobre la regulación del balance energético; 2) las bases genómicas para el desarrollo de la obesidad, 3) las vías celulares de las funciones del tejido adiposo; 4) la descripción molecular del estado obeso; 5) las consecuencias patológicas de la obesidad; 6) las bases fisiológicas para las estrategias de tratamiento. El tejido adiposo es reconocido hoy en día como un órgano endocrino clave, cuya comunicación amplia es efectuada tanto con el cerebro como con tejidos periféricos a través de estas adipocinas. La obesidad es caracterizada por una inflamación moderada y el adipocito parece ser el sitio principal de este estado inflamatorio, que lo estimula a producir citocinas, quimiocinas, proteínas de fase aguda, y factores angiogénicos. En este artículo, discutiremos las vías de señalizaciones celulares y moleculares que se encuentran en las intersecciones de los caminos inflamatorios y metabólicos que contribuyen al desarrollo de la diabetes y la disfunción endotelial a través de un exceso de grasa corporal. También nos atrevemos a sugerir varios modelos que pretenden explicar la integración de las vías inflamatorias y metabólicas dentro del contexto de las enfermedades del metabolismo y la obesidad.

Obesity is a multidisciplinary topic, the biology of which includes: 1) the f fundamental mechanisms of energy balance and its regulation; 2) the genomic basis for the development of obesity; 3) the cellular pathways of adipose tissue function; 4) the molecular description of the obese state; 5) the pathological consequences of obesity; 6) the physiological basis for treatment strategies. Adipose tissue is now recognized as a key endocrine organ, communicating both with the brain and peripheral tissues through the adipokines. Obesity is characterized by mild inflammation, and the adipocyte may be the main locus of the inflammatory state, producing cytokines, chemokines, acute-phase proteins and angiogenic factors. In this article, we discuss the molecular and cellular signaling pathways at the intersection of metabolism and inflammation that contribute to diabetes and endothelial dysfunction through an excess of body fat. We dare to suggest several models for the integration of inflammatory and metabolic pathways in metabolic disease and obesity.