The hallmarks of cancer.

Background The HER2 gene, which encodes the growth factor receptor HER2, is amplified and HER2 is overexpressed in 25 to 30 percent of breast cancers, increasing the aggressiveness of the tumor. Methods We evaluated the efficacy and safety of trastuzumab, a recombinant monoclonal antibody against HER2, in women with metastatic breast cancer that overexpressed HER2. We randomly assigned 234 patients to receive standard chemotherapy alone and 235 patients to receive standard chemotherapy plus trastuzumab. Patients who had not previously received adjuvant (postoperative) therapy with an anthracycline were treated with doxorubicin (or epirubicin in the case of 36 women) and cyclophosphamide with (143 women) or without trastuzumab (138 women). Patients who had previously received adjuvant anthracycline were treated with paclitaxel alone (96 women) or paclitaxel with trastuzumab (92 women). Results The addition of trastuzumab to chemotherapy was associated with a longer time to disease progression (median, 7.4 ...

Use of Chemotherapy plus a Monoclonal Antibody against HER2 for Metastatic Breast Cancer That Overexpresses HER2

Putative endothelial cell (EC) progenitors or angioblasts were isolated from human peripheral blood by magnetic bead selection on the basis of cell surface antigen expression In vitro, these cells differentiated into ECs In animal models of ischemia, heterologous, homologous, and autologous EC progenitors incorporated into sites of active angiogenesis These findings suggest that EC progenitors may be useful for augmenting collateral vessel growth to ischemic tissues (therapeutic angiogenesis) and for delivering anti- or pro-angiogenic agents, respectively, to sites of pathologic or utilitarian angiogenesis

http://science.sciencemag.org/content/sci/275/5302/964.full.pdf

Isolation of putative progenitor endothelial cells for angiogenesis.

Recent discoveries of endogenous negative regulators of angiogenesis, thrombospondin, angiostatin and glioma-derived angiogenesis inhibitory factor, all associated with neovascularized tumours, suggest a new paradigm of tumorigenesis. It is now helpful to think of the switch to the angiogenic phenotype as a net balance of positive and negative regulators of blood vessel growth. The extent to which the negative regulators are decreased during this switch may dictate whether a primary tumour grows rapidly or slowly and whether metastases grow at all.

Angiogenesis in cancer, vascular, rheumatoid and other disease

The transforming growth factor beta (TGF-beta) family of growth factors control the development and homeostasis of most tissues in metazoan organisms. Work over the past few years has led to the elucidation of a TGF-beta signal transduction network. This network involves receptor serine/threonine kinases at the cell surface and their substrates, the SMAD proteins, which move into the nucleus, where they activate target gene transcription in association with DNA-binding partners. Distinct repertoires of receptors, SMAD proteins, and DNA-binding partners seemingly underlie, in a cell-specific manner, the multifunctional nature of TGF-beta and related factors. Mutations in these pathways are the cause of various forms of human cancer and developmental disorders.

TGF-beta signal transduction.

Phosphotyrosine-specific phosphatase PTP-SL regulates the ERK5 signaling pathway.

Negative Regulation of HER2 Signaling by the PEST-type Protein-tyrosine Phosphatase BDP1

Skeletal muscle insulin resistance plays a pivotal role in the pathogenesis of non-insulin-dependent diabetes mellitus (NIDDM), as individuals with this defect are at increased risk of developing the disease later in life To assess whether the abnormal expression of the structurally distinct human insulin receptor isoforms, HIR-A and HIR-B, which has been found in skeletal muscle of NIDDM patients, is a feature of a prediabetic state, skeletal muscle biopsies from nondiabetic individuals ranging from high insulin sensitivity to insulin resistance were examined Polymerase chain reaction analysis of mRNA from muscle biopsies detected exclusive or predominant expression of HIR-A in 13 patients with normal insulin sensitivity In contrast, 7 subjects with various degrees of insulin resistance exhibited abnormally increased HIR-B RNA expression This association suggests the abnormal expression of receptor isoforms as a characteristic of the prediabetic state and supports the notion of a connection of this aberration with the pathogenesis of NIDDM Changes in HIR-A/B expression in the skeletal muscle may thus provide a prognostic criterion for the development of NIDDM

Insulin receptor isotype expression correlates with risk of non-insulin-dependent diabetes.

The extracellular matrix protein lectin galactoside-binding soluble 3 binding protein (LGALS3BP) constitutes a negative prognostic marker of cancer onset and progression with increasing value in clinical application. Since its discovery, however, although the glycoprotein has been implicated in a growing number of disease-related processes, its actual role and mechanism of action have remained ambiguous, thus hindering opportunities for therapeutic development. In this study, we have determined that LGALS3BP constitutes a novel ligand for integrins α1β1, α5β1, αvβ1 and α6β1 and have identified that these newly established partnerships at the membrane level are responsible for exerting the molecule's involvement in cancer through manipulation of multiple canonical 'outside-in' integrin signalling events. We demonstrate that LGALS3BP-mediated integrin activation results into signal transmission via Akt, JNK and the Ras cascade via the Raf-ERK axis while p38 activity is kept at baseline levels. Transient cellular adherence to LGALS3BP favours survival and proliferation signalling while apoptosis is kept at bay. Sustained cellular exposure to LGALS3BP significantly supports viability, motility and migration. Importantly, an anti-LGALS3BP antibody, SP2 is capable of impeding these newly defined LGALS3BP-driven processes without, however, compromising cell viability. These novel findings reveal the mechanism of action of LGALS3BP during cellular adherence and warrant its further validation as a potential pharmacological target for anticancer therapies.

LGALS3BP, lectin galactoside-binding soluble 3 binding protein, promotes oncogenic cellular events impeded by antibody intervention

A recently described tumor-derived glycoprotein, designated 90K, has been shown to have positive effects on the generation of cytotoxic effector cells (NK/LAK) from human PBMC. To determine the mechanism of these effects, we have examined the effects of 90K on cytokine production by human PBMC. A culture of normal PBMC with 90K alone did not result in IL-2 secretion; however, in coculture with suboptimal doses of ConA, 90K increased IL-2 secretion by PBMC. Coculture of PBMC with 90K and ConA also resulted in increased production of the cytokines IL-1, IL-6, GM-CSF, and TNF alpha. T cells depleted of accessory cells failed to respond to ConA alone, 90K alone, or the combination of ConA and 90K, suggesting that this protein does not have a direct effect on T cells. However, 90K alone was sufficient to induce cytokine production by unfractionated PBMC (IL-1, IL-6, GM-CSF, and TNF alpha) or by CD14-enriched PBMC (IL-1 and IL-6). In addition, expression of ICAM-1 was increased on a human monocytic cell line cultured with purified 90K in the absence of any other stimulus. This 90K-induced upregulation of ICAM-1 expression was accompanied by an increased accessory function of the monocytes, demonstrated by their ability to support ConA-induced activation of peripheral blood T cells. Based on the current data, we propose a model in which 90K activates accessory cells, resulting in the secretion of cytokines and the expression of adhesion molecules, which in turn act as costimulatory signals for T-cell activation. Activated T cells then produce cytokines such as IL-2, which lead to a more vigorous cell-mediated immune response to tumor cells and virus-infected cells. Thus, 90K shows promise as an immunotherapeutic reagent for diseases such as cancer and viral infection.

Axel Ullrich

Papers

Phosphotyrosine-specific phosphatase PTP-SL regulates the ERK5 signaling pathway.

Negative Regulation of HER2 Signaling by the PEST-type Protein-tyrosine Phosphatase BDP1

Insulin receptor isotype expression correlates with risk of non-insulin-dependent diabetes.

LGALS3BP, lectin galactoside-binding soluble 3 binding protein, promotes oncogenic cellular events impeded by antibody intervention

A tumor-derived protein which provides T-cell costimulation through accessory cell activation