Insulin‐like growth factor‐binding protein‐2 in patients with prostate carcinoma and benign prostatic hyperplasia

Abstract

Serum IGFBP-2 levels are uniquely elevated in active prostate carcinoma but not. In benign prostatic hyperplasia. In prostate carcinoma, serum IGFBP-2 levels closely parallel those of prostate-specific antigen and probably reflect tumour burden. The relationship between prostatic-specific antigen and IGFBP-2 is partially independent of their individual relationships with age. Although serum IGFBP-2 is less sensitive than prostate-specific antigen in prostate carcinoma it may have adjunctive value in its management.

Insulin-like growth factor 1 in relation to prostate cancer and benign prostatic hyperplasia

“…This is in marked contrast to our data demonstrating that serum IGF-I and IGF-2 levels were not different in patients with prostate cancer relative to age-matched controls (Cohen et al, 1993). Similarly, Ho and Baxter (1997) found normal IGF-1 levels in the sera of patients with prostate cancer. The IGFs circulate complexed to a family of proteins known as the IGF-binding proteins (IGFBPs), as reviewed by Daughaday et al (1986).…”

“…We have also recently found a twofold elevation in the serum levels of IGFBP-4 in the sera of prostate cancer patients. Our findings of elevated IGFBP-2 in prostate cancer patients have also been replicated by Kanety et al (1993) and Ho and Baxter (1997). As IGFBP-2 and IGFBP-4 are not removed by the ethanol extraction method used by Mantzoros et al (1997), we believe that their patients actually had normal serum IGF-1 levels, but elevated serum IGFBP-2 and IGFBP-4 levels, leading to an artifactual elevation in the IGF-1 RIA reading.…”

“…While many data exist in support of a role for the IGF system in the pathogenesis of prostate cancer, it is the autocrine-paracrine involvement of IGFs and IGFBPs that is commonly implicated, as reviewed by Peehl et al (1996). However, measurements of IGF-1 in two previous studies using valid methodologies (Cohen et al, 1993;Ho and Baxter, 1997), demonstrated normal serum levels, indicating that there is no relationship between circulating IGF-I levels and the prevalence of prostate cancer. We would therefore like to encourage Mantzoros et al (1997) to re-assay their patients' sera in an IGF-I assay, which can be demonstrated to be free of IGFBP interference; otherwise, their conclusions may not be valid.…”

“…There is a lesson here: lack of statistical significance is frequently due to limited statistical power and should never be the basis for a confident assertion of no association. The other study that Cohen and colleagues refer to (Ho and Baxter, 1997) is even smaller than their own, with only seven controls.…”

Impact of diet on prostate cancer: a review

“…33 Second, others have focused on the free radicals produced by dietary fat as the relevant factor. 34 Proinflammatory fatty acid metabolites such as specific leukotrienes and prostaglandins may also be carcinogenic and promote tumor growth. 35 In addition, dietary fat reduction may impact serum insulin-like growth factor levels in the serum.…”