J Urol 2003 Feb;169(2):714-7 Related Articles, Links
Plasma levels of insulin-like growth factor-1 and binding protein-3, and their association with bladder cancer risk.
Zhao H, Grossman HB, Spitz MR, Lerner SP, Zhang K, Wu X.
Department of Epidemiology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA.
PURPOSE: Because insulin-like growth factors (IGFs) and their binding proteins have been implicated in the development of prostate, breast, colon and lung cancer, we examined the role of IGF-1 and IGF binding protein-3 levels in bladder cancer risk. MATERIALS AND METHODS: We used an enzyme-linked immunosorbent assay to compare plasma levels of IGF-1 and IGF binding protein-3 in 154 patients with bladder cancer and 154 controls from an ongoing case-control study. RESULTS: Mean IGF-1 was significantly higher in cases than in controls (175.8 versus 153.2 ng./ml., p <0.01). Mean IGF binding protein-3 was significantly lower in cases than in controls (2,632.9 versus 3,056.6 ng./ml., p <0.01). The highest quartile plasma levels of IGF-1 were associated with an increased risk of bladder cancer (OR 3.10, 95% CI 1.43 to 6.70) and the highest quartile plasma levels of IGF binding protein-3 were associated with a reduced risk of bladder cancer (OR 0.38, 95% CI 0.19 to 0.78). The effects were more striking when IGF-1 and IGF binding protein-3 levels were analyzed together. In addition, a higher molar ratio of IGF-1-to-IGF binding protein-3 was associated with an increased risk of bladder cancer (OR 4.30, 95% CI 1.99 to 9.28). Dose-response relationships were evident when subjects were categorized into quartiles by the values of IGF-1, IGF binding protein-3 and the molar ratio in controls. CONCLUSIONS: To our knowledge this is the first study to suggest that patients with bladder cancer have higher plasma levels of IGF-1 and lower levels of IGF binding protein-3 than controls. Thus, measuring plasma IGF-1 and IGF binding protein-3 may be useful for assessing bladder cancer risk.
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J Natl Cancer Inst 1999 Jan 20;91(2):151-6 Related Articles, Links
Plasma levels of insulin-like growth factor-I and lung cancer risk: a case-control analysis.
Yu H, Spitz MR, Mistry J, Gu J, Hong WK, Wu X.
Section of Cancer Prevention and Control, Feist-Weiller Cancer Center, Louisiana State University Medical Center, Shreveport, USA.
BACKGROUND: Insulin-like growth factors (IGFs), in particular IGF-I and IGF-II, strongly stimulate the proliferation of a variety of cancer cells, including those from lung cancer. To examine the possible causal role of IGFs in lung cancer development, we compared plasma levels of IGF-I, IGF-II, and an IGF-binding protein (IGFBP-3) in patients with newly diagnosed lung cancer and in control subjects. METHODS: From an ongoing hospital-based, case-control study, we selected 204 consecutive patients with histologically confirmed, primary lung cancer and 218 control subjects who were matched to the case patients by age, sex, race, and smoking status. IGF-I, IGF-II, and IGFBP-3 plasma levels were measured by enzyme-linked immunosorbent assay and then divided into quartiles, based on their distribution in the control subjects. Associations between the IGF variables and lung cancer risk were estimated by use of odds ratios (ORs). Reported P values are two-sided. RESULTS: IGF and IGFBP-3 levels were positively correlated (all r>.27; all P<.001). High plasma levels of IGF-I were associated with an increased risk of lung cancer (OR = 2.06; 95% confidence interval [CI] = 1.19-3.56; P = .01), and this association was dose dependent in both univariate and multivariate analyses. Plasma IGFBP-3 showed no association with lung cancer risk unless adjusted for IGF-I level; when both of these variables were analyzed together, high plasma levels of IGFBP-3 were associated with reduced risk of lung cancer (OR = 0.48; 95% CI = 0.25-0.92; P = .03). IGF-II was not associated with lung cancer risk. CONCLUSIONS: Plasma levels of IGF-I are higher and plasma levels of IGFBP-3 are lower in patients with lung cancer than in control subjects. If these findings can be confirmed in prospective studies, measuring levels of IGF-I and IGFBP-3 in blood may prove useful in assessing lung cancer risk.
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J Natl Cancer Inst 2000 Dec 6;92(23):1910-7 Related Articles, Links
Comment in:
J Natl Cancer Inst. 2001 Apr 18;93(8):649-51.
Plasma insulin-like growth factor-I, insulin-like growth factor-binding proteins, and prostate cancer risk: a prospective study.
Stattin P, Bylund A, Rinaldi S, Biessy C, Dechaud H, Stenman UH, Egevad L, Riboli E, Hallmans G, Kaaks R.
Department of Urology and Andrology, Umea University Hospital, Sweden. par.stattin@urologi.umu.se
BACKGROUND: Recent studies have suggested that men with elevated plasma levels of insulin-like growth factor-I (IGF-I) may have an increased risk of prostate cancer. Furthermore, IGF-binding proteins (IGFBPs) and insulin can modulate the activity of IGF-I. In this study, we sought to determine the role of IGF-I as well as IGFBPs-1, -2, and -3 and insulin as possible etiologic factors for prostate cancer. METHODS: We conducted a nested case-control study within the Northern Sweden Health and Disease Cohort Study. We measured levels of IGF-I, IGFBP-1, IGFBP-2, IGFBP-3, and insulin in plasma samples from 149 men who had a diagnosis of prostate cancer between 1 month and 10 years after blood collection and among 298 control men. All statistical tests are two-sided. RESULTS: Case subjects had statistically significantly higher mean levels of IGF-I than control subjects (229 ng/mL; 95% confidence interval [CI] = 218-240 ng/mL] versus 214 ng/mL [95% CI = 208-221 ng/mL]; P =.02) and IGFBP-3 (2611 ng/mL [95% CI = 2518-2704 ng/mL] versus 2498 ng/mL [95% CI = 2437-2560 ng/mL]; P =.04). Conditional logistic regression analyses showed increases in prostate cancer risk with rising levels of IGF-I (P:(for trend) =.02) and IGFBP-3 (P(for trend) =.03). In case subjects younger than 59 years at the time of blood collection, the risk associated with increased IGF-I was higher (P:(for trend) =.01), whereas the risk associated with increased IGFBP-3 was lower (P(for trend) =.44) than the corresponding risks in the full cohort. Prostate cancer risk was not associated with levels of IGFBP-1, IGFBP-2, or insulin. CONCLUSIONS: Prostate cancer risk is increased in men with elevated plasma IGF-I. This association was particularly strong in younger men in this study, suggesting that circulating IGF-I may be specifically involved in the early pathogenesis of prostate cancer. |
