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Biomedical subjects

Robert Stein

Publications and source records attributed to Robert Stein.

7 recordsLinked to original sources
PubMed2005

Tumour-stromal interactions in breast cancer: the role of stroma in tumourigenesis.

Mammary stromal tissue has a major role in the control and regulation of physiological processes in the breast. Recently, the function of stroma in supporting the tumourigenic process as well as responding to the oncogenic lesion has become clearer. This review differs from the conventional view in that it focuses on and discusses the newly available evidence that points to the fact that mammary stroma has a significant contribution in actively generating transformed lesions and tumours. As such, the oncogenic signals can be dependent or independent of genetic mutations in mammary stromal cells. As a supportive and responsive agent in tumourigenesis, the stroma is induced by tumour cells to express critical signals that drive proliferation, angiogenesis, and motility while suppressing cell death. As an oncogenic agent in tumourigenesis, the stroma can provoke tumourigenicity in adjacent cells in the absence of pre-existing tumour cells leading to the acquisition of genomic changes. Investigating the mechanism by which the tumourigenic cues of the stroma facilitate the generation of malignant epithelial cells will provide invaluable insights into the oncogenic process.

Animals↗
PubMed2004

Video-assisted thoracoscopic surgery of mediastinal bronchogenic cysts in adults: a single-center experience.

BACKGROUND: Mediastinal bronchogenic cysts are rarely diagnosed in adults, hence surgical experience is limited particularly with regard to video-assisted thoracoscopic surgery. In support of the thoracoscopic approach we report our single-center experience in this rare entity. METHODS: Between June 1995 and December 2002, a nonselected series of 12 consecutive patients presenting with mediastinal bronchogenic cysts underwent video-assisted thoracoscopic surgery. Six cysts (50%) had been diagnosed 2 to 22 years prior, only three of which became symptomatic. In asymptomatic patients (n = 7) surgery was performed because of increasing cyst size (n = 3), patient's request (n = 3), or suspected metastasis (n = 1). RESULTS: Mediastinal bronchogenic cysts were correctly diagnosed by computed tomography in 83% (10/12) and by magnetic resonance imaging in 100% (9/9). Using a three-trocar technique thoracoscopic surgery was successfully performed in 11 of 12 cases (92%). We noted no signs of acute cyst infection. No serious postoperative complications were observed. In 1 patient conversion to open thoracotomy was necessary due to extensive pleural adhesions. In another case thoracoscopic excision of the cyst wall was incomplete. Patients with thoracoscopic excision were discharged after a median of 5.5 days (range 4 to 14 days). No recurrences or complications were observed during a mean follow-up of 40.5 months. CONCLUSIONS: Considering the low conversion and complication rate in our series, video-assisted thoracoscopic surgery should be the primary therapeutic choice among adults with symptomatic mediastinal bronchogenic cysts. Surgical intervention in patients with asymptomatic and uncomplicated cysts appears optional.

Adult↗
PubMed2004

Three-dimensional in vitro tissue culture models of breast cancer-- a review.

Three-dimensional (3D) in vitro breast tumour models have an invaluable role in tumour biology today providing some very important insights into breast cancer. As well as increasing our understanding of homeostasis, cellular differentiation and tissue organization they provide a well defined environment for cancer research in contrast to the complex host environment of an in vivo model. With the recent availability of relevant stromal elements together with the vast array of extracellular matrix constituents available, in vivo like microenvironments can be recreated. These tissue like structures more realistically model the structural architecture and differentiated function of breast cancer than a cellular monolayer providing in vivo like responses to therapeutic agents. Three dimensional in vitro models allow the study of cell-cell and cell-extracellular matrix interactions, in addition to the influence of the microenvironment on cellular differentiation, proliferation, apoptosis and gene expression. Due to their enormous potential 3D cultures are currently being exploited by many other branches of biomedical science with therapeutically orientated studies becoming the major focus of research. In return great progress in 3D culture techniques have been made, largely due to this greater interaction. At present they are being used in studies ranging from investigating the role of adhesion molecules (e.g., E-cadherin) in invasion/metastasis; VEGF and angiogenesis, to tissue modelling and remodelling. Progress in the development of complex 3D culture systems is more productive than ever, however further research is vital.

Breast Neoplasms↗
PubMed2003

Models of breast cancer: is merging human and animal models the future?

Survival rates of patients with early breast cancer in the United Kingdom and in the United States have improved steadily over the past 15 years. The only way to continue or even accelerate this progress, however, is the discovery and development of new preventative and therapeutic strategies. With the massive explosion in potential therapeutic strategies becoming available, in the postgenomic era, better and more representative breast cancer models are urgently required for preclinical trials. Development of better in vivo models of human breast cancer are thus of crucial importance in the development of new cancer therapeutics.

Animals↗
PubMed2003

Synchronous bilateral typical pulmonary carcinoid tumors.

A 73-year-old woman was admitted with bilateral pulmonary nodules, one on each side, which were suspected to be metastases of an unknown primary tumor. Enucleation of the lesion in the upper right lobe was performed. The histological examination showed a typical carcinoid tumor. A subsequent octreotid scan revealed high suspicion of a carcinoid in the left lower lobe as well. Formal right upper lobectomy and left lower lobectomy were performed in staged procedures. The radiological 1 year control with CT-scan demonstrated no further pathological lesions. To the best of our knowledge this is the first description of curable synchronous pulmonary carcinoid tumors.

Aged↗