Subcellular Localization and Transport Kinetics of Ruthenium Organometallic Anticancer Compounds in Living Cells: A Dose-Dependent Role for Amino Acid and Iron Transporters:

Ruthenium-based compounds are developed for anticancer treatment, but their mode of action including their import mechanism and subcellular localization remains elusive. Here, we used the intrinsic luminescent properties of cytotoxic organoruthenium (Ru(II)) compounds obtained with an anionic cyclometalated 2-phenylpyridine chelate and neutral aromatic chelating ligands (e.g., phenanthrolines) to follow their behavior in living cells. We established that the difference in sensitivity between cancer cells and noncancerous cells toward one of the compounds correlates with its import kinetics and follows a balance between active and passive transport. The active-transport mechanism involves iron and amino-acid transporters, which are transcriptionally regulated by the drug. We also demonstrated a correlation between the accumulation of these compounds in specific compartments (endoplasmic reticulum, nucleus, mitochondria) and the activation of specific cytotoxic mechanisms such as the rnitochondrial stress pathway. Our study pinpoints a novel and complex mechanism of accumulation of ruthenium drugs in cancer cells

Induction of caspase 8 and reactive oxygen species by ruthenium-derived anticancer compounds with improved water solubility and cytotoxicity

Organometallic compounds which contain metals, such as ruthenium or gold, have been investigated as a replacement for platinum-derived anticancer drugs. They often show good antitumor effects, but the identification of their precise mode of action or their pharmacological optimization is still challenging. We have previously described a class of ruthenium(II) compounds with interesting anticancer properties. In comparison to cisplatin, these molecules have lower side effects, a reduced ability to interact with DNA, and they induce cell death in absence of p53 through CHOP/DDIT3. We have now optimized these molecules by improving their cytotoxicity and their water solubility. In this article, we demonstrate that by changing the ligands around the ruthenium we modify the ability of the compounds to interact with DNA. We show that these optimized molecules reduce tumor growth in different mouse models and retain their ability to induce CHOP/DDIT3. However, they are more potent inducers of cancer cell death and trigger the production of reactive oxygen species and the activation of caspase 8. More importantly, we show that blocking reactive oxygen species production or caspase 8 activity reduces significantly the activity of the compounds. Altogether our data suggest that water-soluble ruthenium(II)-derived compounds represent an interesting class of molecules that, depending on their structures, can target several pro-apoptotic signaling pathways leading to reactive oxygen species production and caspase 8 activation

Induction of caspase 8 and reactive oxygen species by ruthenium-derived anticancer compounds with improved water solubility and cytotoxicity

Organometallic compounds which contain metals, such as ruthenium or gold, have been investigated as a replacement for platinum-derived anticancer drugs. They often show good antitumor effects, but the identification of their precise mode of action or their pharmacological optimization is still challenging. We have previously described a class of ruthenium(II) compounds with interesting anticancer properties. In comparison to cisplatin, these molecules have lower side effects, a reduced ability to interact with DNA, and they induce cell death in absence of p53 through CHOP/DDIT3. We have now optimized these molecules by improving their cytotoxicity and their water solubility. In this article, we demonstrate that by changing the ligands around the ruthenium we modify the ability of the compounds to interact with DNA. We show that these optimized molecules reduce tumor growth in different mouse models and retain their ability to induce CHOP/DDIT3. However, they are more potent inducers of cancer cell death and trigger the production of reactive oxygen species and the activation of caspase 8. More importantly, we show that blocking reactive oxygen species production or caspase 8 activity reduces significantly the activity of the compounds. Altogether our data suggest that water-soluble ruthenium(II)-derived compounds represent an interesting class of molecules that, depending on their structures, can target several pro-apoptotic signaling pathways leading to reactive oxygen species production and caspase 8 activation. (C) 2012 Elsevier Inc. All rights reserved

Videolaparoscopic cholecystectomy. Analysis of the clinical and functional aspects of mechanical lifting of the abdominal wall Colecistectomia videolaparoscópica. Análise de aspectos clínicos e funcionais da suspensão mecânica da parede abdominal

Background - Mechanical lifting of the abdominal wall, a method based on traction and consequent elevation of the abdominal wall, is an alternative procedure to create enough intra-abdominal space necessary for videolaparoscopic surgery, dispensing the need for intraperitoneal gas insufflation. Objective - This study aims to evaluate the technical feasibilility of this procedure to carry out a videolaparoscopic cholecystectomy, while analyzing the clinical and functional aspects of this technique. Patients and Methods - In the Digestive Tract Surgery Discipline of the Medical School at the University of São Paulo, São Paulo, SP, Brazil, was created the equipment to perform videolaparoscopic surgery using this method. The equipment has two sections: an external part which consisted of a frame attached to the operating table, inside which there is a sliding steel cable, moved by a ratched which is located at the lower end of one of the frame rods; the internal rod, the support, has an "L" shape, and its horizontal branch is made up of three turning rods and which is connected to the steel cable after insertion into the abdominal cavity. Ten patients underwent videolaparoscopic cholecystectomy using this equipment. The time taken to install the equipment, the operating area characteristics, the interference from the lifting equipment on surgical movements and on the intra-operative cholangiography, the measurements made of the force used during traction and extension of the abdominal wall elevation, and the medication required for post-operative analgesia were all evaluated. Results - There were no intra-operative complications, and in none of the cases was it found necessary to convert to open surgery. We considered the insertion a safe and uncomplicated procedure, and the traction system efficient. Apart from the elevation of the abdominal wall, the distribution of the viscera inside the abdominal cavity is fundamental for the operating area. Depending on the position of the epigastric trocar, the lifting equipment can interfere with the surgical instruments mobility. It may be necessary to reposition the support to perform the intra-operative cholangiography. The tensional force applied to the peritoneal surface by the lifting rods is small, and no additional post-operative pain was observed using this procedure. Conclusion - These results show that using the equipment described in this study, mechanical lifting of the abdominal wall is a feasible alternative for undertaking videolaparoscopic cholecystectomy.<br>Racional - A suspensão mecânica da parede abdominal, método baseado no mecanismo de tração e conseqüente elevação da parede abdominal, é procedimento alternativo para a criação de adequado espaço intra-abdominal necessário à cirurgia videolaparoscópica, prescindindo-se da insuflação gasosa intra-peritonial. Objetivo - Avaliar a viabilidade técnica desse procedimento para realização da colecistectomia videolaparoscópica, com a análise de aspectos clínicos e funcionais da suspensão mecânica da parede abdominal. Pacientes e Métodos - Na Disciplina de Cirurgia do Aparelho Digestivo da Faculdade de Medicina da Universidade de São Paulo foi criado equipamento para realização de cirurgia videolaparoscópica por esse método, constituído de duas partes: a externa consiste em um pórtico acoplado à mesa operatória, no interior do qual desliza um cabo de aço que é tracionado por um sistema de catraca presente na extremidade inferior de uma das hastes do pórtico; a interna, o dispositivo suspensor, tem o formato em "L", cujo ramo horizontal é constituído de três hastes giratórias, o qual é conectado ao cabo de aço após introdução na cavidade abdominal. Com esse equipamento 10 pacientes foram submetidos a colecistectomia videolaparoscópica; em um deles foi associada hiatoplastia e fundoplicatura. Foram avaliados o tempo de instalação do equipamento, as características do campo operatório, a interferência provocada pela presença do equipamento de suspensão nos movimentos operatórios e nas imagens da colangiografia intra-operatória; foram medidas a força aplicada na tração e a extensão da elevação da parede abdominal e, por fim, a necessidade de medicação para analgesia pós-operatória. Resultados - Não houve qualquer complicação intra-operatória, não sendo necessária conversão para cirurgia aberta em nenhum caso. Observou-se facilidade e segurança na introdução do suspensor, bem como eficácia do sistema de tração. No campo operatório, além da elevação da parede abdominal, desempenha papel fundamental o nível de distribuição das vísceras no interior da cavidade. Dependendo da posição do trocarte epigástrico, a presença do equipamento de suspensão pode interferir na movimentação dos instrumentos. Para realização da colangiografia intra-operatória pode ser necessário o reposicionamento do suspensor. É pequena a força tensional aplicada na superfície peritoneal pelas hastes do suspensor, não se observando qualquer indicativo de maior dor pós-operatória com esse procedimento. Conclusão - Em face desses resultados, a suspensão mecânica da parede abdominal, realizada com o equipamento descrito nesse trabalho, é alternativa viável para realização da colecistectomia videolaparoscópica