AS129 - Association of diabetes and insulin-like growth factor-I (IGF-I) with risks of colorectal, breast, and endometrial cancer

Investigator Names and Contact Information

Howard Strickler (howard.strickler@einsteinmed.org)

Introduction/Intent

Increasing evidence indicates that high serum insulin-like growth factor-I (IGF-I) is associated with elevated risk of colorectal, breast, and endometrial cancer. Three Insulin Resistance Syndrome-related conditions, type 2 diabetes, obesity, and sedentary lifestyle, are also associated with greater risk of these cancers, and hyperinsulinemia is hypothesized to drive these relationships, at least in part. Insulin shares 40% sequence homology with IGF-I, and biological studies indicate that they are both mitogens. However, few epidemiologic studies have evaluated cancer risk based on insulin levels, and none have been prospective with sufficient sample size or adequate control for confounders. Similarly, there are sparse epidemiologic data regarding free IGF-I and cancer, even though the unbound form is the main bioactive component.

An initial cross-sectional pilot study by our group found that free IGF-I was more strongly associated with breast cancer than total IGF-I (see Reprint #5). To provide definitive evidence of their associations with cancer, a prospective epidemiologic investigation of insulin and free IGF-I is needed. Studies must also consider histologic type, grade of neoplasia, stage at diagnosis and, in breast cancer, estrogen receptor status, since insulin and IGF-I both have effects on the estrogen receptor. The potential impact of race on these associations is another gap in our knowledge. Few minority women were included in previous investigations, even though rates of diabetes, the relation of obesity and mortality, serum IGF-I levels, and risks of cancer, all vary by race. Moreover, little is known regarding the factors that influence IGF-I levels in elderly women.

The purpose of this application is to prospectively study the effects of high serum levels of insulin and free IGF-I on risk of colorectal, breast and endometrial cancer in postmenopausal women. Specimens and data will be obtained from the Observational Study (OS) of the Women’s Health Initiative (WHI), a large (n=93,725), ethnically and geographically diverse cohort of postmenopausal women aged 50-79. We propose conducting a case-cohort investigation, testing baseline serum samples for fasting levels of glucose, insulin, total and free IGF-I, IGF binding protein-3 (IGFBP-3), and total estradiol. WHI-OS subjects selected for this study will have been in the cohort an average of 7 years, with cases excluded if diagnosed during the first 18 months. We will study all colorectal (n=500), endometrial (n=300), and half of the 1900 breast cancer (n=900) cases that are expected, as well as a random subset of the whole cohort (subcohort n=900), to address the following specific aims:

  1. To prospectively study the independent effects of high serum insulin and free IGF-I on risk of colorectal, breast and endometrial cancer in postmenopausal women, by using a case-cohort investigation to assess:
  • The relation of fasting levels of glucose and insulin, insulin resistance (i.e., HOMA index - a measure of the glucose/insulin steady state calculated from fasting levels), total estradiol, total and free IGF-I, as well as IGFBP-3, with incident cancers.
  • The strengths of these associations according to histologic type, tumor grade, stage at diagnosis and, in the case of breast cancer, sex hormone receptor status.
  1. To determine within the subcohort the factors related to levels of total IGF-I, free IGF-I and IGFBP-3, including age, race, obesity, hormone replacement therapy, use of insulin, prescription medicines, nutrition (e.g., food frequency questionnaire data), and lifestyle factors (e.g., exercise). These results will be essential in assessing confounders in Specific Aim #1 and, moreover, it will be of scientific, perhaps clinical, relevance to identify the modifiable and unmodifiable factors correlated with IGF-I levels.

  2. To assess whether type 2 diabetes is an independent risk factor for colorectal, breast and endometrial cancer, after controlling for insulin resistance (HOMA index), total IGF-I, free IGF-I and IGFBP-3, by:

  • Using fasting glucose levels to find subjects with undiagnosed diabetes (fasting glucose >125 mg/dl) and impaired fasting glucose (IFG; fasting glucose 110-125 mg/dl), a source of misclassification in most earlier studies, and which together involve >15% of women over age 50.
  • Studying the risk of incident cancers in diabetics relative to those without either diabetes or IFG.

Materials/Methods

This study proposes an investigation to prospectively study the effects of high insulin and insulin-like growth factor-I (IGF-I) levels on risk of colorectal, breast, and endometrial cancers in postmenopausal women. Baseline serum specimens will be obtained from the Women’s Health Initiative (WHI) Observational Study (OS), a large (n=93,725), ethnically and geographically diverse cohort of postmenopausal women aged 50-79 at baseline, enrolled between 1993-1998, and followed annually.

A case-cohort design will be used because it is more efficient than nested case-control for evaluation of multiple outcomes.

Results/Findings

Some of the publications related to this ancillary study are: 459, 460, 461, 1173.

Ms459 - Gunter MJ, Hoover DR, Yu H, Wassertheil-Smoller S, Manson JE, Li J, Harris TG, Rohan TE, Xue X, Ho GY, Einstein MH, Kaplan RC, Burk RD, Wylie-Rosett J, Pollak MN, Anderson G, Howard BV, Strickler HD. A prospective evaluation of insulin and insulin-like growth factor-I as risk factors for endometrial cancer. Cancer Epidemiol Biomarkers Prev. 2008 Apr;17(4):921-9.

Ms460 - Gunter MJ, Hoover DR, Yu H, Wassertheil-Smoller S, Rohan TE, Manson JE, Howard BV, Wylie-Rosett J, Anderson GL, Ho GY, Kaplan RC, Li J, Xue X, Harris TG, Burk RD, Strickler HD. Insulin, insulin-like growth factor-I, endogenous estradiol, and risk of colorectal cancer in postmenopausal women. Cancer Res. 2008 Jan 1;68(1):329-37.

Ms461 - Gunter MJ, Hoover DR, Yu H, Wassertheil-Smoller S, Rohan TE, Manson JE, Li J, Ho GY, Xue X, Anderson GL, Kaplan RC, Harris TG, Howard BV, Wylie-Rosett J, Burk RD, Strickler HD. Insulin, insulin-like growth factor-I, and risk of breast cancer in postmenopausal women. J Natl Cancer Inst. 2009 Jan 7;101(1):48-60. Epub 2008 Dec 30.

Ms1173 - Hvidtfeldt UA, Gunter MJ, Lange T, Chlebowski RT, Lane DS, Farhat GN, Freiberg MS, Keiding N, Lee JS, Prentice R, Tjonneland A, Vitolins MZ, Wassertheil-Smoller S, Strickler HD, Rod NH. Quantifying mediating effects of endogenous estrogen and insulin in the relation between obesity, alcohol consumption and breast cancer. Cancer Epidemiol Biomarkers Prev. 2012 May 7. [Epub ahead of print]

For a complete, up-to-date list of WHI papers related to this ancillary study, please use the searchable Bibliography section of this website. To search for papers by study number, access the Simple Search, and enter the study number in the “Related Studies” field.

Data Dictionaries and Study Documentation

This section displays all study-related data dictionaries and study-related files. The investigators for this study will upload the datasets, data dictionaries, and other study-related files. Study-related files will be made available to the public one year after the completion of the ancillary study, with the exception of the datasets, which will only be available to those with a Data Distribution Agreement. Those will be available to those with permission to download and will appear as a download link next to the data dictionary

Data Dictionaries

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Description
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Study Documents

Name
Description
NameAS129 subject selection 1-30-02 summary.pdfDescription

Related Papers

Genetic variants and traits related to insulin-like growth factor-I and insulin resistance and their interaction with lifestyles on postmenopausal colorectal cancer risk

Su Yon Jung et al., 2017/10 PubMed #29023587 MSID: 3146
Genetic variants and traits in metabolic signaling pathways may interact with lifestyle factors such as obesity, physical activity, and exogenous estrogen (E), influencing postmenopausal colorectal cancer (CRC) risk, but these interrelated pathways are not fully understood. In this case-cohort study, we examined 33 single-nucleotide polymorphisms (SNPs) in genes related to insulin-like growth factor-I (IGF-I)/ insulin resistance (IR) traits and signaling pathways, using data from 704 postmenopau...
Keywords: Colorectal Cancer Risk; Insulin Resistance; Glucose Metabolism-Relevant Single-Nucleotide Polymorphism; Obesity; Postmenopausal Women
Related Studies: 129, 152

A prospective evaluation of insulin and insulin-like growth factor-I as risk factors for endometrial cancer

Marc Gunter et al., 2008/4 PubMed #18398032 MSID: 459
Obesity is a major risk factor for endometrial cancer, a relationship thought to be largely explained by the prevalence of high estrogen levels in obese women. Obesity is also associated with high levels of insulin, a known mitogen. However, no prospective studies have directly assessed whether insulin and/or insulin-like growth factor-I (IGF-I), a related hormone, are associated with endometrial cancer while accounting for estrogen levels. We therefore conducted a case-cohort study of incident ...
Keywords: Insulin-Like Growth Factor-I (Igf-I); Igf Binding Protein-3 (Igfbp-3) Estradiol; Endometrial Cancer; Hormone Replacement Therapy; Case-Cohort Design.
Related Studies: 129

Insulin, insulin-like growth factor-I, and risk of breast cancer in postmenopausal women

Marc Gunter et al., 2008/12 PubMed #19116382 MSID: 461
The positive association between obesity and postmenopausal breast cancer has been attributed, in part, to the fact that estrogen, a risk factor for breast cancer, is synthesized in adipose tissue. Obesity is also associated with high levels of insulin, a known mitogen. However, no prospective studies have directly assessed associations between circulating levels of insulin and/or insulin-like growth factor (IGF)-I, a related hormone, and the risk of breast cancer independent of estrogen level.W...
Keywords: Insulin-Like Growth Factor-I (Igf-I); Igf Binding Protein-3 (Igfbp-3) Estradiol; Breast Cancer; Hormone Replacement Therapy; Case-Cohort Design.
Related Studies: 129

Circulating adipokines and inflammatory markers and postmenopausal breast cancer risk

Marc Gunter et al., 2015/7 PubMed #26185195 MSID: 1061
Adipokines and inflammation may provide a mechanistic link between obesity and postmenopausal breast cancer, yet epidemiologic data on their associations with breast cancer risk are limited.In a case-cohort analysis nested within the Women's Health Initiative Observational Study, a prospective cohort of postmenopausal women, baseline plasma samples from 875 incident breast cancer case patients and 839 subcohort participants were tested for levels of seven adipokines, namely leptin, adiponectin, ...
Keywords: Breast Cancer; Adipokine; Insulin; Obesity
Related Studies: 126, 129, BA10

Quantifying mediating effects of endogenous estrogen and insulin in the relation between obesity, alcohol consumption and breast cancer

Ulla Arthur Hvidtfeldt et al., 2012/5 PubMed #22564867 MSID: 1173
BACKGROUND: Increased exposure to endogenous estrogen and/or insulin may partly explain the relationship of obesity, physical inactivity, and alcohol consumption and postmenopausal breast cancer. However, these potential mediating effects have not been formally quantified in a survival analysis setting. METHODS: We combined data from two case-cohort studies based in the Women's Health Initiative-Observational Study with serum estradiol levels, one of which also had insulin levels. A total of 1,6...
Keywords: Lifestyle; Estrogens; Breast Cancer; Postmenopause; Mediating Effects
Related Studies: 129, 167, BA21

Insulin, insulin-like growth factor-I, endogenous estradiol, and risk of colorectal cancer in postmenopausal women

Marc Gunter et al., 2008/1 PubMed #18172327 MSID: 460
Obesity is a risk factor for colorectal cancer, and hyperinsulinemia, a common condition in obese patients, may underlie this relationship. Insulin, in addition to its metabolic effects, has promitotic and antiapoptotic activity that may be tumorigenic. Insulin-like growth factor (IGF)-I, a related hormone, shares sequence homology with insulin, and has even stronger mitogenic effects. However, few prospective colorectal cancer studies directly measured fasting insulin, and none evaluated free I...
Keywords: Insulin-Like Growth Factor-I (Igf-I); Igf Binding Protein-3 (Igfbp-3); Estradiol; Colorectal Cancer; Case-Cohort Design.
Related Studies: 129

Interaction of insulin-like growth factor-I and insulin resistance–related genetic variants with obesity and lifestyle factors on postmenopausal breast cancer risk

Su Yon Jung et al., 2017/5 PubMed #28478612 MSID: 2679
PURPOSE: Genetic variants and traits in metabolic signaling pathways may interact with obesity, physical activity, and exogenous estrogen (E), influencing postmenopausal breast cancer risk, but these inter-related pathways are incompletely understood. METHODS: We used 75 single-nucleotide polymorphisms (SNPs) in genes related to insulin-like growth factor-I (IGF-I)/insulin resistance (IR) traits and signaling pathways, and data from 1003 postmenopausal women in Women's Health Initiative Observat...
Keywords: Breast Cancer; Exogenous Estrogen; Insulin-Like Growth Factor-I/Insulin Resistance-Related Genetic Variant; Obesity; Physical Activity; Postmenopausal Women
Related Studies: 129, 152

Evaluation of differences in the association of insulin/IGF axis components with breast cancer risk by estrogen receptor status in a case-cohort investigation: a formal analysis

Approved Proposal, Cai, Jainwen et al., 2009/4 MSID: 959
Keywords: Insulin; Insulin-Like Growth Factor (Igf-I; Igf-Bp3); Er Positive And Er Negative Breast Cancer; Case-Cohort Design
Related Studies: 129

Association between endophenotypic targets of Metformin and type 2 diabetes risk using mendelian randomization approach

Approved Proposal, Chan, Kei-Hang Katie et al., 2015/8 MSID: 2742
Keywords: Genes; Metformin; Biochemical Markers; T2d; Mendelian Randomization
Related Studies: 129, 132, 238

Breast cancer risk in metabolically healthy but overweight postmenopausal women

Marc Gunter et al., 2015/1 PubMed #25593034 MSID: 1614
Adiposity is an established risk factor for postmenopausal breast cancer. Recent data suggest that high insulin levels in overweight women may play a major role in this relationship, due to insulin's mitogenic/antiapoptotic activity. However, whether overweight women who are metabolically healthy (i.e., normal insulin sensitivity) have elevated risk of breast cancer is unknown. We investigated whether overweight women with normal insulin sensitivity [i.e., homeostasis model assessment of insulin...
Keywords: Obesity; Insulin Resistance; Metabolic Syndrome; Breast Cancer; Colorectal Cancer; Healthy Obese
Related Studies: 129

A prospective study of soluble receptor for advanced glycation end-products and colorectal cancer risk in postmenopausal women

Liang Chen et al., 2016/4 PubMed #27100837 MSID: 1901
OBJECTIVES: Receptor for advanced glycation end products (RAGE) expressed on adipocytes and immune cells can bind to ligand Ne-(carboxymethyl)-lysine (CML) and trigger dysregulation of adipokines and chronic inflammation. Soluble RAGE (sRAGE) mitigates the detrimental effect of RAGE. We examined the associations between circulating levels of CML-AGE and sRAGE and colorectal cancer (CRC). METHODS: In a case-cohort study of the Women's Health Initiative Study, blood levels of CML-AGE and sRAGE wer...
Keywords: Advanced Glycation End-Products; Body Weight; Colorectal Cancer; Epidemiology; N(E)-(Carboxymethyl)-Lysine; Obesity; Pattern Recognition Receptors; Receptor For Advanced Glycosylation End-Products; Srage
Related Studies: 129, 292

Adiposity and breast, endometrial, and colorectal cancer risk in postmenopausal women: Quantification of the mediating effects of leptin, C-reactive protein, fasting insulin, and estradiol

Seyedeh Dashti et al., 2022/1 PubMed #35048536 MSID: 3809
Background: Mechanisms underlying the adiposity-cancer relationship are incompletely understood. We quantified the mediating roles of C-reactive protein (CRP), leptin, fasting insulin, and estradiol in the effect of adiposity on estrogen receptor (ER)-positive breast, endometrial, and colorectal cancer risk in postmenopausal women. Methods: We used a case-cohort study within the Women's Health Initiative Observational Study, analyzed as a cumulative sampling case-control study. The study include...
Keywords: Adiposity; Causal Mediation Analysis; Inflammation; C-Reactive Protein; Insulin; Estrogens; Estradiol; Breast Cancer; Endometrial Cancer; Colorectal Cancer
Related Studies: 129, BA10

Associations of serum insulin-like growth factor-I and insulin-like growth factor-binding protein 3 levels with biomarker-calibrated protein, dairy product and milk intake in the Women's Health Initiative

Jeannette Beasley et al., 2013/10 PubMed #24094144 MSID: 1586
It is well established that protein-energy malnutrition decreases serum insulin-like growth factor (IGF)-I levels, and supplementation of 30 g of whey protein daily has been shown to increase serum IGF-I levels by 8 % after 2 years in a clinical trial. Cohort studies provide the opportunity to assess associations between dietary protein intake and IGF axis protein levels under more typical eating conditions. In the present study, we assessed the associations of circulating IGF axis protein level...
Keywords: Protein; Biomarker Calibration; Igf-I; Igfbp-3; Free Igf
Related Studies: 129

Testing the proportionality of the hazards in case-cohort studies

Xiaonan ""Nan"" Xue et al., 2013/7 PubMed #23834739 MSID: 1891
Case-cohort studies have become common in epidemiological studies of rare disease, with Cox regression models the principal method used in their analysis. However, no appropriate procedures to assess the assumption of proportional hazards of case-cohort Cox models have been proposed.We extended the correlation test based on Schoenfeld residuals, an approach used to evaluate the proportionality of hazards in standard Cox models. Specifically, pseudolikelihood functions were used to define ""case-...
Keywords: Proportionality; Schoenfeld Residual; Case-Cohort Study; Cox Proportional Hazards Model; Pseudo-Likelihood Function
Related Studies: 129