Radiotherapy in breast cancer: current standards of treatment, prediction of local recurrence and open questions

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Galectin-1 as a potential cancer target

Galectins are a family of structurally related carbohydrate-binding proteins, which are defined by their affinity for poly-N-acetyllactosamine-enriched glycoconjugates and sequence similarities in the carbohydrate recognition domain. Galectin-1, a member of this family, contributes to different events associated with cancer biology, including tumour transformation, cell cycle regulation, apoptosis, cell adhesion, migration and inflammation. In addition, recent evidence indicates that galectin-1 contributes to tumour evasion of immune responses. Given the increased interest of tumour biologists and clinical oncologists in this field and the potential use of galectins as novel targets for anticancer drugs, we summarise here recent advances about the role of galectin-1 in different events of tumour growth and metastasis

Cell cycle and aging, morphogenesis, and response to stimuli genes are individualized biomarkers of glioblastoma progression and survival

<p>Abstract</p> <p>Background</p> <p>Glioblastoma is a complex multifactorial disorder that has swift and devastating consequences. Few genes have been consistently identified as prognostic biomarkers of glioblastoma survival. The goal of this study was to identify general and clinical-dependent biomarker genes and biological processes of three complementary events: lifetime, overall and progression-free glioblastoma survival.</p> <p>Methods</p> <p>A novel analytical strategy was developed to identify general associations between the biomarkers and glioblastoma, and associations that depend on cohort groups, such as race, gender, and therapy. Gene network inference, cross-validation and functional analyses further supported the identified biomarkers.</p> <p>Results</p> <p>A total of 61, 47 and 60 gene expression profiles were significantly associated with lifetime, overall, and progression-free survival, respectively. The vast majority of these genes have been previously reported to be associated with glioblastoma (35, 24, and 35 genes, respectively) or with other cancers (10, 19, and 15 genes, respectively) and the rest (16, 4, and 10 genes, respectively) are novel associations. <it>Pik3r1</it>, <it>E2f3, Akr1c3</it>, <it>Csf1</it>, <it>Jag2</it>, <it>Plcg1</it>, <it>Rpl37a</it>, <it>Sod2</it>, <it>Topors</it>, <it>Hras</it>, <it>Mdm2, Camk2g</it>, <it>Fstl1</it>, <it>Il13ra1</it>, <it>Mtap </it>and <it>Tp53 </it>were associated with multiple survival events.</p> <p>Most genes (from 90 to 96%) were associated with survival in a general or cohort-independent manner and thus the same trend is observed across all clinical levels studied. The most extreme associations between profiles and survival were observed for <it>Syne1</it>, <it>Pdcd4</it>, <it>Ighg1</it>, <it>Tgfa</it>, <it>Pla2g7</it>, and <it>Paics</it>. Several genes were found to have a cohort-dependent association with survival and these associations are the basis for individualized prognostic and gene-based therapies. <it>C2</it>, <it>Egfr</it>, <it>Prkcb</it>, <it>Igf2bp3</it>, and <it>Gdf10 </it>had gender-dependent associations; <it>Sox10</it>, <it>Rps20</it>, <it>Rab31</it>, and <it>Vav3 </it>had race-dependent associations; <it>Chi3l1</it>, <it>Prkcb</it>, <it>Polr2d</it>, and <it>Apool </it>had therapy-dependent associations. Biological processes associated glioblastoma survival included morphogenesis, cell cycle, aging, response to stimuli, and programmed cell death.</p> <p>Conclusions</p> <p>Known biomarkers of glioblastoma survival were confirmed, and new general and clinical-dependent gene profiles were uncovered. The comparison of biomarkers across glioblastoma phases and functional analyses offered insights into the role of genes. These findings support the development of more accurate and personalized prognostic tools and gene-based therapies that improve the survival and quality of life of individuals afflicted by glioblastoma multiforme.</p

Galectin-1, a gene preferentially expressed at the tumor margin, promotes glioblastoma cell invasion

BACKGROUND: High-grade gliomas, including glioblastomas (GBMs), are recalcitrant to local therapy in part because of their ability to invade the normal brain parenchyma surrounding these tumors. Animal models capable of recapitulating glioblastoma invasion may help identify mediators of this aggressive phenotype. METHODS: Patient-derived glioblastoma lines have been propagated in our laboratories and orthotopically xenografted into the brains of immunocompromized mice. Invasive cells at the tumor periphery were isolated using laser capture microdissection. The mRNA expression profile of these cells was compared to expression at the tumor core, using normal mouse brain to control for host contamination. Galectin-1, a target identified by screening the resulting data, was stably over-expressed in the U87MG cell line. Sub-clones were assayed for attachment, proliferation, migration, invasion, and in vivo tumor phenotype. RESULTS: Expression microarray data identified galectin-1 as the most potent marker (p-value 4.0 x 10(-8)) to identify GBM cells between tumor-brain interface as compared to the tumor core. Over-expression of galectin-1 enhanced migration and invasion in vitro. In vivo, tumors expressing high galectin-1 levels showed enhanced invasion and decreased host survival. CONCLUSIONS: In conclusion, cells at the margin of glioblastoma, in comparison to tumor core cells, have enhanced expression of mediators of invasion. Galectin-1 is likely one such mediator. Previous studies, along with the current one, have proven galectin-1 to be important in the migration and invasion of glioblastoma cells, in GBM neoangiogenesis, and also, potentially, in GBM immune privilege. Targeting this molecule may offer clinical improvement to the current standard of glioblastoma therapy, i.e. radiation, temozolomide, anti-angiogenic therapy, and vaccinotherapy

Use of mTOR inhibitors in the treatment of breast cancer: an evaluation of factors that influence patient outcomes

Guy Jerusalem, Andree Rorive, Joelle Collignon Medical Oncology, CHU Sart Tilman Liege, Domaine Universitaire du Sart Tilman, Liege, Belgium Abstract: Many systemic treatment options are available for advanced breast cancer, including endocrine therapy, chemotherapy, anti-human epidermal growth factor receptor 2 (HER2) therapy, and other targeted agents. Recently, everolimus, a mammalian target of rapamycin (mTOR) inhibitor, combined with exemestane, an aromatase inhibitor, has been approved in Europe and the USA for patients suffering from estrogen receptor-positive, HER2-negative advanced breast cancer previously treated by a nonsteroidal aromatase inhibitor, based on the results of BOLERO-2 (Breast cancer trials of OraL EveROlimus). This study showed a statistically significant and clinically meaningful improvement in median progression-free survival. Results concerning the impact on overall survival are expected in the near future. This clinically oriented review focuses on the use of mTOR inhibitors in breast cancer. Results reported with first-generation mTOR inhibitors (ridaforolimus, temsirolimus, everolimus) are discussed. The current and potential role of mTOR inhibitors is reported according to breast cancer subtype (estrogen receptor-positive HER2-negative, triple-negative, and HER2-positive ER-positive/negative disease). Everolimus is currently being evaluated in the adjuvant setting in high-risk estrogen receptor-positive, HER2-negative early breast cancer. Continuing mTOR inhibition or alternatively administering other drugs targeting the phosphatidylinositol-3-kinase/protein kinase B-mTOR pathway after progression on treatments including an mTOR inhibitor is under evaluation. Potential biomarkers to select patients showing a more pronounced benefit are reviewed, but we are not currently using these biomarkers in routine practice. Subgroup analysis of BOLERO 2 has shown that the benefit is consistent in all subgroups and that it is impossible to select patients not benefiting from addition of everolimus to exemestane. Side effects and impact on quality of life are other important issues discussed in this review. Second-generation mTOR inhibitors and dual mTOR-phosphatidylinositol-3-kinase inhibitors are currently being evaluated in clinical trials. Keywords: breast cancer, treatment, everolimus, mTOR inhibitors, biomarkers, phosphatidylinositol-3-kinase/protein kinase B-mTOR pathwa

La beta-2-microglobuline plasmatique en hémodialyse itérative, marquer du risque d'amyloïdose?

Certains patients insuffisants rénaux chroniques hémodialysés au long cours souffrent de lésions kystiques ostéo-articulaires ou présentent un syndrome du canal carpien (4). Assez récemment, des dépôts de substance amyloïde ont été observés au niveau de ces lésions (2,10). Parmi ces dépôts, on a pu identifier une protéine de structure et de poids moléculaire voisin de la bêta-2-microglobuline (B2M) (6). Cette substance, normalement métabolisée au niveau du tube contourné proximal rénal, tendrait à s'accumuler chez le patient urémique traité par hémodialyse (HO) conventionnelle à l'aide d'une membrane en cuprophane et à se déposer dans les tissus et participer ainsi à la formation des fibrilles d'amyloïde. La prévalence de cette complication augmenterait avec le nombre d'années en HD(5,9). Le but de cette étude était de vérifier si le taux plasmatique de B2M constituait un bon prédicteur du risque d'amyloïdose chez des patients hémodialysés en chronique sur membrane en cuprophane, particulièrement impliquée dans la pathogénie de cette complication

Does Dopamine Play a Role in Renal Anomaly in Sodium Excretion, a Marker for Hereditary Predisposition to Arterial Hypertension?

peer reviewedSince Dahl's observation, a renal defect os sodium excretion is proposed as one of pathogenetic mechanism of hypertension (HTA). Our study has tried to verify this concept in 20 young normotensives with (n = 12) and without (n = 8) familial predisposition to HTA, allowing to test the genetic transmission of such potential renal abnormality of sodium balance. Each people was submitted to 3 different Na diet (20, 170 and 340 mM NaCl) each for 1 week. At each visit, blood pressure, vascular resistances, biological values were determined at rest (plasma renin activity, creatinine clearance, 24 hours before the test, catecholamines, aldosterone and ion urinary excretion). Then 1 liter of isotonic saline was perfused in 30 minutes with measures of blood pressure and 3 hours urinary dopamine and Na excretion. During the low and medium Na diets, but not during the high Na diet, the natriuresis and dopamine excretion were lower in the 3 hour urine collection in patients with a family history of HTA (p less than 0.02 and p less than 0.005, respectively). No other clinical or biological difference was noted between the 2 groups. Thus, genetic hypertensive predisposition seems to be characterized by a lower Na excretion during acute Na loading in normal or depleted Na diet, linked to an impaired urinary dopamine excretion. These findings suggest that the defect responsible for the susceptibility to sodium intake is at the kidney level. Some dopamine agonists would be of great therapeutical value in treating such patients when blood pressure begins to rise