Oral candidiasis in cancer patients.

Oral candidiasis in cancer patients is an infection for which inconsistent diagnostic and therapeutic strategies currently prevail. Recent studies have shown its potential importance in the development of systemic candidiasis. A clinical and cytologic study was undertaken on 52 consecutive cancer patients admitted to our institution. Although the incidence of clinical candidiasis was low (8%), 27% of patients harbored evidence of subclinical colonization by Candida. In addition, a significant correlation was found between candidal colonization and low absolute lymphocyte counts. The significance of these findings in relation to systemic candidiasis and rationale for therapy are discussed

Insulin-like growth factor binding protein 1 stimulates cell migration and binds to the alpha 5 beta 1 integrin by means of its Arg-Gly-Asp sequence.

Insulin-like growth factor (IGF)-binding protein 1 (IGFBP-1) contains an Arg-Gly-Asp (RGD) integrin recognition sequence. In vitro mutagenesis was used to alter this RGD sequence to Trp-Gly-Asp (WGD). Migration of Chinese hamster ovary (CHO) cells expressing the wild-type protein was more than 3-fold greater in 48 hr compared with cells expressing the WGD mutant form of IGFBP-1. Similarly, wild-type IGFBP-1 added to the media of control CHO cells stimulated migration 2-fold compared with the WGD protein. A synthetic RGD-containing peptide, when added to the medium with wild-type IGFBP-1, blocked the effect of IGFBP-1 on cell migration. The addition of IGF-I to the culture medium had no effect on the migration of cells expressing IGFBP-1 or vector alone. Affinity chromatography of 125I-labeled CHO cell membrane proteins, using IGFBP-1 coupled to agarose, identified the alpha 5 beta 1 integrin (fibronectin receptor) as the only cell surface molecule capable of binding IGFBP-1 in an RGD-dependent manner. Furthermore, wild-type IGFBP-1, but not the WGD mutant form, could be coprecipitated from CHO cells with an antibody directed against the alpha 5 integrin subunit. These studies demonstrate that IGFBP-1 stimulates CHO cell migration and binds to the alpha 5 beta 1 integrin receptor, both by an RGD-dependent mechanism. The effect of IGFBP-1 on migration is independent of IGF-I and is probably mediated through the alpha 5 beta 1 integrin

Renal lymphoma in an azotemic patient--usefulness of magnetic resonance imaging

An azotemic patient benefited from diagnostic magnetic resonance imaging (MRI) in the evaluation of his renal mass. This led to suspicion of lymphoma, and provided guidance for percutaneous biopsy. Chemotherapy was then initiated, and an unnecessary nephrectomy was avoided. After a year of follow-up, evolution was stable and renal function significantly improved

Extracellular matrix contains insulin-like growth factor binding protein-5: potentiation of the effects of IGF-I.

Abstract. Insulin-like growth factor binding proteins (IGFBPs) have been shown to serve as carrier proteins for the insulin-like growth factors (IGFs) and to modulate their biologic effects. Since extracellular matrix (ECM) has been shown to be a reservoir for IGF-I and IGF-U, we examined the ECM of cultured human fetal fibroblasts and found that IGFBP-5 was incorporated intact into ECM, while mostly inert proteolytic fragments were found in the medium. In contrast, two other forms of IGFBP that are secreted by these cells were either present in ECM in minimal amounts (IGFBP-3) or not detected (IGFBP-4). Likewise, when purified IGFBPs were incubated with ECM, IGFBP-5 bound preferentially. IGFBP-5 was found to bind to types III and IV collagen, laminin, and fibronectin