Common genetic variation within IGFI, IGFII, IGFBP-1, and IGFBP-3 and endometrial cancer risk

Association between IGFBP1 expression and cancer risk: A systematic review and meta-analysis

Background

The results regarding the association between insulin-like growth factor binding protein 1 (IGFBP1) expression and cancer risk were controversial. We performed a meta-analysis to provide novel evidence on relationship between IGFBP1 expression and cancer risk.

Methods

PubMed, Embase, Cochrane library and Web of science were searched for relevant cohort and case-control studies exploring the relationship between IGFBP1 expression and cancer risk. Odds ratios (ORs) were pooled in this meta-analysis using random model. Subgroup analyses were performed based on ethnicity, tumor types, publication year, study type, Newcastle-Ottawa Scale (NOS) score and sex.

Results

A total of 27 studies including 16 cohort and 11 case-control studies were identified by literature search. No significant association was found between IGFBP1 expression and risk of various cancers [0.90, 95% confidence interval (CI): 0.79, 1.03]. The overall results showed that the pooled ORs were 0.71 (95% CI: 0.57, 0.88] for prostate cancer risk and 0.66 (95%CI: 0.44, 0.99) for colorectal cancer (CRC) risk. However, there is no significant association between IGFBP1 expression and risk for ovarian cancer (1.70, 95%CI: 0.41, 6.99), breast cancer (1.02, 95%CI: 0.85, 1.23), endometrial cancer (1.19, 95%CI: 0.64, 2.21), colorectal adenoma (0.93; 95%CI: 0.81, 1.07), lung cancer (0.81, 95%CI: 0.39, 1.68) or multiple myeloma (1.20, 95%CI: 0.98, 1.47).

Conclusion

In this study, compared with individuals at low IGFBP1 expression adjusted for age, smoking status, alcohol intake and so on, risk of the prostate cancer and CRC were decreased among individuals of high IGFBP1 expression. There needs further study to confirm this issue.

Role of IGF2 in the Study of Development and Evolution of Prostate Cancer

Prostate Cancer (PC) is commonly known as one of the most frequent tumors among males. A significant problem of this tumor is that in early stages most of the cases course as indolent forms, so an active surveillance will anticipate the appearance of aggressive stages. One of the main strategies in medical and biomedical research is to find non-invasive biomarkers for improving monitoring and performing a more precise follow-up of diseases like PC. Here we report the relevant role of IGF2 and miR-93-5p as non-invasive biomarker for PC. This event could improve current medical strategies in PC.

IGFBP-1 in cancer: expression, molecular mechanisms, and potential clinical implications

Insulin-like growth factor binding protein-1 (IGFBP-1) belongs to the insulin-like growth factor (IGF) system, which plays an indispensable role in normal growth and development, and in the pathophysiology of various tumors. IGFBP-1 has been shown to be associated with the risk of various tumors, and has a vital function in regulating tumor behaviors such as proliferation, migration, invasion and adhesion through different molecular mechanisms. The biological actions of IGFBP-1 in cancer are found to be related to its phosphorylation state, and the IGF-dependent and -independent mechanisms. In this review, we provided an overview of IGFBP-1 in normal physiology, and its aberrantly expression and the underlying molecular mechanisms in a range of common tumors, as well as discussed the potential clinical implications of IGFBP-1 as diagnostic or prognostic biomarkers in cancer.

Association of polymorphisms of preptin, irisin and adropin genes with susceptibility to coronary artery disease and hypertension

OBJECTIVES

Preptin, irisin and adropin are 3 new players in energy regulation that are related body mass index, lipids, glucose and insulin levels which may affect incidence of cardiovascular diseases. The aim of the present study was to evaluate eight single nucleotide polymorphisms (SNPs) of preptin genes (rs1003483, rs1004446, rs2239681, rs680, and rs3741204), irisin (rs16835198 and rs3480) and adropin (rs2281997) gene in patients with coronary artery disease (CAD) and hypertension.

METHODS

This case-control study was carried out on 372 volunteers, which were divided into 3 subgroups including: CAD patients with hypertension (CAD+H+), CAD patients with no hypertension (CAD+H-), and non-hypertensive non-CAD subjects as control group (CAD-H-) as health control. Genomic DNA from whole blood was extracted and eight SNPs were assessed using polymerase chain reaction- ligase detection reaction method.

RESULTS

A significant difference was found in the genotype and allele frequency of preptin rs1003483 gene in CAD+H+ compared to CAD+H- groups (P = .019 and P = .018, respectively). Allele frequency of rs1003483 was significantly different between CAD+H- groups and healthy control groups (P = .043). There also existed a significant difference the genotype frequency of rs1004446 gene in CAD+H+ compared to CAD+H- groups (P = .027).

CONCLUSIONS

The findings of present study revealed that the preptin rs1003483 and rs1004446 gene polymorphism might serve as predisposing factor in CAD and hypertension.

Growth hormone co-treatment on controlled ovarian stimulation in normal ovarian response women can improve embryo quality

To investigate the clinical efficacy of growth hormone (GH) in normal response patients with poor embryo quality in previous in vitro fertilization cycles. A total of 1562 infertile women were enrolled in this matched case-control study: 781 women were treated with GH (study group), whereas 781 matched patients were treated without GH (control group). GH was administered by a daily subcutaneous injection of 2 or 4 IU started from either D2 of the previous cycle (6 weeks GH pretreatment) or the initial day of controlled ovarian stimulation (2 weeks GH pretreatment) until hCG trigger. The study group was further divided into four subgroups: 2 IU-6 weeks GH pretreatment, 4 IU-6 weeks GH pretreatment, 2 IU-2 weeks GH pretreatment, and 2 IU-4 weeks GH pretreatment. Patients receiving GH showed significantly lower Gn dosage. The total number of oocytes retrieved, embryos formed, endometrial thickness on hCG day were significantly higher with GH. 2PN rate and high-quality embryo rate were lower in the GH group. However, GH increased clinical pregnancy rate with significant difference. 4 IU-6 weeks GH pretreatment showed lowest duration of Gn and highest clinical pregnancy rate compared with other three groups. Number of transferred embryos was confounding factor both in univariate and multivariate analysis. Our study showed that co-treatment with GH in patients with normal ovarian response could increase pregnancy rate.

Association of IGF-1 CA(n) and IGFBP3 rs2854746 Polymorphisms with Endometrial Polyp Risk

INTRODUCTION

Insulin-like growth factor 1 (IGF-1) is a peptide growth factor that promotes cell proliferation and inhibits apoptosis. The bioavailability of IGF-1 is regulated by the insulin-like growth factor binding protein 3 (IGFBP3). Genetic variations influence the levels of IGF-1 and IGFBP3. The purpose of this study was to examine the association of polymorphisms IGF-1 CA(n) and IGFBP3 rs2854746 with risk of endometrial polyps.

MATERIALS AND METHODS

Case control observational study, composed of 104 women with antecedent of endometrial polyp (case group) and 81 postmenopausal women without antecedent of endometrial diseases (control group). Genotyping of IGF-1 CA(n) was performed by PCR and fragment analysis by capillary electrophoresis, and genotyping of IGFBP3 rs2854746 was performed by PCR-HRM. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by logistic regression.

RESULTS

The genotype IGF-1 CA(19)/CA(19) was associated with an increased endometrial polyp risk (OR=2,57; IC 95%= 1,09 - 6,01); this was also found when combining it with CA(>19)/CA(n) genotypes (OR=2,18; IC 95%= 1,06-4,47). The IGFBP3 rs2854746 analyses showed the CG genotype having a protective effect for endometrial polyp (OR=0,37; IC 95%= 0,19-0,73), fact also observed when grouping CG and GG carriers (OR=0,51; IC 95%= 0,28-0,93).

CONCLUSION

The genotypes CA(19)/CA(19) and CA(19)/CA(19) + CA(>19)/CA(n) of the IGF-1 CA(n) may be considered a risk for endometrial polyp, whereas the genotypes CG and CG + GG of IGFBP3 rs2854746 polymorphism have an inverse effect of endometrial polyp risk.

Relationship between insulin-like growth factor axis gene polymorphisms and clinical outcome in advanced gastric cancer patients treated with FOLFOX

The insulin-like growth factor (IGF) axis plays a crucial role in proliferation, differentiation, migration, angiogenesis, and apoptosis. The present study evaluated the associations between IGF axis single-nucleotide polymorphisms (SNPs) and clinical outcomes in advanced gastric cancer (AGC) patients treated with oxaliplatin, 5-fluorouracil, and leucovorin (FOLFOX). A total of 190 patients undergoing FOLFOX chemotherapy for AGC were considered eligible for this study. Forty-four SNPs of 10 IGF axis genes were genotyped. Levels of serum IGF1 were measured using enzyme-linked immunoassays. SNPs of the IGF1R (rs12423791), and IGF1 (rs2162679, rs5742612, rs35767) genes were significantly associated with tumor response to FOLFOX. SNPs of rs4619 and rs17847203 were significantly associated with PFS (hazard ratio [HR] 0.575, 95% CI 0.385–0.858, P = 0.007; and HR 2.530, 95% CI 1.289–4.966, P = 0.007; respectively). SNPs of rs2872060 were significantly associated with OS—OS was shorter in patients carrying the TT variant than in those with the GG/GT genotypes (HR, 1.708, 95% CI 1.024–2.850, P = 0.040). The GT genotype of rs12847203 was also identified as an independent prognostic factor (HR 2.087, 95% CI 1.070–4.069, P = 0.031). These results suggest that IGF axis-pathway SNPs could be used as prognostic biomarkers of the outcome of FOLFOX chemotherapy in AGC patients. This information may facilitate identification of population subgroups that could benefit from IGF1R-targeted agents.

Insulin-like growth factor (IGF) axis in cancerogenesis

Determination of the role of insulin-like growth factor (IGF) family components in carcinogenesis of several human tumors is based on numerous epidemiological and pre-clinical studies, experiments in vivo and in vitro and on attempts at application of drugs affecting the IGF axis. Investigative hypotheses in original studies were based on biological functions manifested by the entire family of IGF (ligands, receptors, linking proteins, adaptor molecules). In the context of carcinogenesis the most important functions of IGF family involve intensification of proliferation and inhibition of cell apoptosis and effect on cell transformation through synthesis of several regulatory proteins. IGF axis controls survival and influences on metastases of cells. Interactions of IGF axis components may be of a direct or indirect nature. The direct effects are linked to activation of PI3K/Akt signaling pathway, in which the initiating role is first of all played by IGF-1 and IGF-1R. Activity of this signaling pathway leads to an increased mitogenesis, cell cycle progression, and protection against different apoptotic stresses. Indirect effects of the axis depend on interactions between IGF and other molecules important for cancer etiology (e.g. sex hormones, products of suppressor genes, viruses, and other GFs) and the style of life (nutrition, physical activity). From the clinical point of view, components of IGF system are first of all considered as diagnostic serous and/or tissue biomarkers of a given cancer, prognostic factors and attractive target of modern anti-tumor therapies. Several mechanisms in which IGF system components act in the process of carcinogenesis need to be clarified, mainly due to multifactorial etiology of the neoplasms. Pin-pointing of the role played in carcinogenesis by any single signaling pathway remains particularly difficult. The aim of this review is to summarize the current data of several epidemiological studies, experiments in vitro and on animal models, to increase our understanding of the complex role of IGF family components in the most common human cancers.

Assessment of Multifactor Gene-Environment Interactions and Ovarian Cancer Risk: Candidate Genes, Obesity, and Hormone-Related Risk Factors

BACKGROUND

Many epithelial ovarian cancer (EOC) risk factors relate to hormone exposure and elevated estrogen levels are associated with obesity in postmenopausal women. Therefore, we hypothesized that gene-environment interactions related to hormone-related risk factors could differ between obese and non-obese women.

METHODS

We considered interactions between 11,441 SNPs within 80 candidate genes related to hormone biosynthesis and metabolism and insulin-like growth factors with six hormone-related factors (oral contraceptive use, parity, endometriosis, tubal ligation, hormone replacement therapy, and estrogen use) and assessed whether these interactions differed between obese and non-obese women. Interactions were assessed using logistic regression models and data from 14 case-control studies (6,247 cases; 10,379 controls). Histotype-specific analyses were also completed.

RESULTS

SNPs in the following candidate genes showed notable interaction: IGF1R (rs41497346, estrogen plus progesterone hormone therapy, histology = all, P = 4.9 × 10(-6)) and ESR1 (rs12661437, endometriosis, histology = all, P = 1.5 × 10(-5)). The most notable obesity-gene-hormone risk factor interaction was within INSR (rs113759408, parity, histology = endometrioid, P = 8.8 × 10(-6)).

CONCLUSIONS

We have demonstrated the feasibility of assessing multifactor interactions in large genetic epidemiology studies. Follow-up studies are necessary to assess the robustness of our findings for ESR1, CYP11A1, IGF1R, CYP11B1, INSR, and IGFBP2 Future work is needed to develop powerful statistical methods able to detect these complex interactions.

IMPACT

Assessment of multifactor interaction is feasible, and, here, suggests that the relationship between genetic variants within candidate genes and hormone-related risk factors may vary EOC susceptibility. Cancer Epidemiol Biomarkers Prev; 25(5); 780-90. ©2016 AACR.

IGFBP3 polymorphisms and risk of esophageal cancer in a Chinese population

Esophageal cancer is the sixth leading cause of cancer-related deaths worldwide. It is very aggressive with a poor prognosis. Besides environmental risk factors, genetic factors might contribute to the esophageal cancer carcinogenesis. To evaluate the association between the risk of esophageal squamous cell carcinoma (ESCC) and genetic variants in IGFBP3, we conducted a hospital-based case-control study to assess the genetic effects of these SNPs. A total of 380 esophageal squamous cell carcinoma (ESCC) cases and 380 controls were recruited for this study. The genotypes were determined using a matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The IGFBP3 single nucleotide polymorphisms (SNPs) rs2270628 C>T, rs10282088 C>A, and rs3110697 G>A were associated with a significantly decreased risk of ESCC. However, our results were obtained with a limited sample size. To confirm the current findings, larger studies with other ethnic populations are required.

Evasion of anti-growth signaling: A key step in tumorigenesis and potential target for treatment and prophylaxis by natural compounds

The evasion of anti-growth signaling is an important characteristic of cancer cells. In order to continue to proliferate, cancer cells must somehow uncouple themselves from the many signals that exist to slow down cell growth. Here, we define the anti-growth signaling process, and review several important pathways involved in growth signaling: p53, phosphatase and tensin homolog (PTEN), retinoblastoma protein (Rb), Hippo, growth differentiation factor 15 (GDF15), AT-rich interactive domain 1A (ARID1A), Notch, insulin-like growth factor (IGF), and Krüppel-like factor 5 (KLF5) pathways. Aberrations in these processes in cancer cells involve mutations and thus the suppression of genes that prevent growth, as well as mutation and activation of genes involved in driving cell growth. Using these pathways as examples, we prioritize molecular targets that might be leveraged to promote anti-growth signaling in cancer cells. Interestingly, naturally occurring phytochemicals found in human diets (either singly or as mixtures) may promote anti-growth signaling, and do so without the potentially adverse effects associated with synthetic chemicals. We review examples of naturally occurring phytochemicals that may be applied to prevent cancer by antagonizing growth signaling, and propose one phytochemical for each pathway. These are: epigallocatechin-3-gallate (EGCG) for the Rb pathway, luteolin for p53, curcumin for PTEN, porphyrins for Hippo, genistein for GDF15, resveratrol for ARID1A, withaferin A for Notch and diguelin for the IGF1-receptor pathway. The coordination of anti-growth signaling and natural compound studies will provide insight into the future application of these compounds in the clinical setting.

Pathological conditions predisposing to infertility and gynaecological neoplasia

Some of the conditions long blamed for female factor infertility are now acknowledged as well established risk factors of gynecological neoplasia. This realization has lead to the proposition that infertility might be a risk factor for the development of several types of gynecological neoplasms. This review addresses different conditions that play a role in both infertility and gynaecological neoplasia. An intricate interplay between growth factors and hormonal factors (estrogens and progestins, androgens and gonadotropins) is said to link the state of infertility to some gynecological tumors. The relation between endometriosis -as one of the well established causes of female infertility - and ovarian cancer is well known. Endometriosis has been particularly related to endometrioid and clear-cell ovarian carcinomas. Another evidence for this association is embodied in finding endometriotic lesions adjacent to ovarian cancers. The polycystic ovary syndrome (PCOS), one of the most prevalent endocrine disorders and a long studied cause of female infertility increases the risk of endometrial carcinoma. The link between PCOS and endometrial carcinoma seems to be endometrial hyperplasia. PCOS-associated endometrial carcinoma tends to present at a younger age and early stage, with lower grade and lower risk of metastasis. Turner’s syndrome and other types of ovarian dysgenesis constitute a rare cause of infertility and are known to confer a definite risk of germ cell tumors. There seems to be a link between infertility and an increased risk of gynecological neoplasia. Hence, it is important to assess the risk of malignancy in each category of infertile patients so as to provide optimal and timely intervention.

Genetic polymorphisms in IGF-I and IGFBP-3 are associated with prostate cancer in the Chinese population

Insulin-like growth factor-I (IGF-I) and IGF binding protein-3 (IGFBP-3) are members of the insulin-like growth factor (IGF) family that play important roles in carcinogenesis. We hypothesized that the functional polymorphisms in IGF-I and IGFBP-3 may be associated with the risk of prostate cancer (PCa) in the Chinese population. This hospital-based case-control study included 664 PCa patients and 702 cancer-free controls. Nine SNPs in IGF-I and IGFBP-3 were genotyped using the TaqMan assay. The genetic associations between the pathogenesis and progression of PCa were assessed by logistic regression. We found that the genotype and allele frequency distribution of rs6218, rs35767 and rs5742612 were significantly different when comparing PCa cases to controls (P  = 0.005, 0.005 and 0.020, respectively). In the combined analysis, individuals with 2–6 risk alleles had an elevated risk of PCa compared to those with 0–1 risk alleles. We also found that the association between the combined risk alleles and the risk of PCa appeared stronger in the following subgroups: individuals older than 71 years of age (OR  = 1.41, 95%CI  = 1.05–1.91, P  = 0.020), nonsmokers (OR  = 1.68, 95%CI  = 1.21–2.32, P  = 0.002), nondrinkers (OR  = 1.32, 95%CI  = 1.02–1.61, P  = 0.002), and those with a negative family history of PCa (OR  = 1.28, 95%CI  = 1.02–1.71, P  = 0.022). Our results indicate that the three SNPs (rs6218, rs35767 and rs5742612) and the joint genotypes with 2–6 risk alleles, may contribute to the susceptibility to PCa, but not the progression, in the Chinese population.

Investigation of insulin resistance gene polymorphisms in patients with differentiated thyroid cancer

We aimed to investigate insulin receptor substrate-1 (IRS-1), insulin receptor substrate-2 (IRS-2), insulin-like growth factor binding protein-3 (IGFBP-3) genotypes, which are thought to be involved in the pathogenesis of many solid tumors and have thus far not been studied in patients with differentiated thyroid cancer (DTC). The study consisted of 93 patients diagnosed with DTC (79 females, 14 males) and 111 healthy control subjects (63 females, 48 males). The anthropometric measurements, lipid profiles, thyroid function tests and homeostatic model assessment (HOMA) as an indicator of insulin resistance (IR) of all patients were recorded. In addition IRS-1, IRS-2 and IGFBP-3 gene polymorphisms were determined by using polymerase chain reaction and restriction fragment length polymorphism. Hardy-Weinberg equilibrium was tested for each gene polymorphisms, and genetic effects were evaluated by the Chi Square test and multiple logistic regression. Homeostasis model assessment of insulin resistance (HOMA-IR), body mass index, waist circumference and serum total cholesterol levels were significantly higher in patients with DTC than in the control group. There was no difference between the two groups with respect to IRS-1, IRS-2 and IGFBP-3 gene polymorphisms. In addition, these gene polymorphisms were found to have no effect on lymph node metastases or tumor staging. While, obesity and increased HOMA-IR may be risk factors in DTC development, we suggest that IRS-1, IRS-2 and IGFBP-3 gene polymorphisms do not play an important role in pathogenesis of DTC.

Overexpression of the insulin receptor isoform A promotes endometrial carcinoma cell growth

Epidemiological studies have demonstrated that type 2 diabetes mellitus (T2DM) and hyperinsulinemia are associated closely with endometrial carcinoma risk, although the molecular mechanism remains unclear. Insulin receptor isoformA expression is upregulated in many cancer cells and tissues, which suggests that IR-A-mediated signaling pathways may have important implications for cancer pathogenesis. We measured the expression of insulin receptor isoforms (IR-A and IR–B in the normal endometrium tissues, the endometrial carcinoma tissues and the endometrial carcinoma cell lines. We found that the total insulin receptor (IR) and IR-A expression mRNA levels and the ratio of IR-A to total IR in endometrial carcinoma specimens were significantly higher than them in control endometrial tissue specimens(P<0.05). Further analysis indicated that the tendency was more prominently in patients with T2DM. IR-A mRNA was differentially expressed in four endometrial carcinoma cell lines (Ishikawa, KLE, RL95-2 and HEC-1-A. RL95-2 cells have a low endogenous IR-A expression, and these were used to construct a stable cell line overexpressing IR-A. We found that IR-A overexpression significantly increased cell proliferation, the proportion of cells in S phase, activation of the Akt pathway and tumorigenicity of xenografts in nude mice. In contrast, there was no significant difference in the the percentage of apoptotic cells between cells overexpressing IR-A and control cells. Moreover, levels of phosphorylated ERK1/2 protein were significantly decreased in cells overexpressing IR-A relative to controls. These findings reveal the pivotal role of IR-A in endometrial cancer carcinogenesis, and suggest that the association of elevated IR-A levels with cell proliferation and tumorigenicity may be causally linked to its effect on the proportion of cells in S phase and the activation of the Akt pathway.

Targeting IGF-1 signaling pathways in gynecologic malignancies

INTRODUCTION

The signaling pathways of the insulin-like growth factors (IGF) have been implicated in the etiology of a number of epithelial neoplasms including prostate, breast, colon and more recently, gynecologic cancers. The insulin-like growth factor-1 receptor (IGF-1R) is expressed in most transformed cells, where it displays potent anti-apoptotic, cell-survival and potentially, transforming activities. IGF-1R expression and activation are typical hallmarks associated with tumor initiation and progression. Multiple approaches have been used to abrogate IGF-1R signaling for targeted cancer therapy including antibodies and small molecule tyrosine kinase inhibitors. These novel IGF-1R targeting agents have produced significant experimental and clinical results in many cancers and generated considerable optimism in the field of cancer therapy.

AREAS COVERED

The authors will review important research advances regarding the role of the IGF axis in cancer, particularly preclinical and clinical studies in cervical, uterine and ovarian cancers. The significance of tumor expression and circulating levels of the IGF pathway as well as targeting therapies of the IGF axis in the gynecologic cancers will be discussed.

EXPERT OPINION

Accumulating data confirm that the IGF-1R pathway has an important role in gynecologic cancers and in vivo and in vitro studies have shown a significant impact of IGF-1R targeted therapies in these malignancies, mainly ovarian and endometrial cancers. Currently, ongoing preclinical and clinical trials are evaluating the efficacy of IGF-1R targeting. A better understanding of the complex mechanisms underlying the regulation of the IGF system will improve the ability to develop effective treatment modalities for these malignancies.

Genetic variability in IGF-1 and IGFBP-3 and body size in early life

Background

Early life body size and circulating levels of IGF-1 and IGFBP-3 have been linked to increased risks of breast and other cancers, but it is unclear whether these exposures act through a common mechanism. Previous studies have examined the role of IGF-1 and IGFBP-3 genetic variation in relation to adult height and body size, but few studies have examined associations with birthweight and childhood size.

Methods

We examined whether htSNPs in IGF-1 and the IGFBP-1/IGFBP-3 gene region are associated with the self-reported outcomes of birthweight, body fatness at ages 5 and 10, and body mass index (BMI) at age 18 among healthy women from the Nurses’ Health Study (NHS) and NHSII. We used ordinal logistic regression to model odds ratios (ORs) and 95% confidence intervals (CI) of a one category increase for birthweight and somatotypes at ages 5 and 10. We used linear regression to model associations with BMI at age 18.

Results

Among 4567 healthy women in NHS and NHSII, we observed no association between common IGF-1 or IGFBP-1/IGFBP-3 SNPs and birthweight, body fatness at ages 5 and 10, or BMI at age 18.

Conclusions

Common IGF-1 and IGFBP-1/IGFBP-3 SNPs are not associated with body size in early life.

Insulin-like growth factors in endometrioid adenocarcinoma: correlation with clinico-pathological features and estrogen receptor expression

Background

Endometrial carcinoma is a common malignancy of female genital tract. Insulin-like growth factor is known to elicit estrogen-induced mitogenic activity and anti-apoptotic effect in endometrial tissues.

Methods

The retrospective study investigated the expression of insulin-like growth factors, estrogen receptors and their associations in endometrioid adenocarcinoma (EAC) from 80 EAC patients in immunohistochemistry, and 58 EAC patients and 42 control patients in quantitative RT-PCR. The Pearson correlation analysis was used to analyze their correlations with clinic-pathological parameters.

Results

Our results showed that insulin-like growth factor-1 and insulin-like growth factor-2 mRNA levels were higher in tumor tissues and tumor-adjacent tissues than those in control cells, and were inversely correlated with the malignancy of the tumor with a positive correlation with ERα and ERβ expression. Insulin-like growth factor-1R protein expression was correlated with clinical stage, and insulin-like growth factor-2R protein expression was inversely correlated with histological grade.

Conclusions

Insulin-like growth factor system plays an important role in estrogen-induced endometrial carcinogenesis, and overexpression of insulin-like growth factor-1R in the advanced endometrioid adenocarcinoma is not estrogen-dependent.

Association between endometriosis and polymorphisms in insulin-like growth factor binding protein genes in Korean women

OBJECTIVE

Genetic factors are known to be associated with the development and progression of endometriosis, but the genes related to endometriosis have not been defined. Insulin-like growth factor binding proteins (IGFBPs) are believed to be involved in the proliferation and apoptosis of cells that play an important role in the pathophysiologic mechanism of endometriosis. This study aimed to determine the association between endometriosis and polymorphisms of the IGFBP genes in Korean women.

STUDY DESIGN

In a case-control study, the rs1995051, rs1065780 and c.759A>G single nucleotide polymorphisms (SNPs) in the IGFBP1 gene and the -672A>G, -202A>C and c.95C>G SNPs in the IGFBP3 gene were analyzed in 128 women with endometriosis and 108 normal control women.

RESULTS

The haplotype genotype composed of a combination of three IGFBP1 gene polymorphisms was not related to endometriosis, while the haplotype genotype of the IGFBP3 gene had a significant association with endometriosis. Women not carrying the AAG (-672A/-202A/c.95G) haplotype allele of three IGFBP3 gene polymorphisms have a 3.19-times higher risk of endometriosis compared with women with AAG homozygotes, and this trend was found in women with advanced endometriosis but not in women with early endometriosis.

CONCLUSIONS

The AAG haplotype allele of the -672A>G, -202A>C and c.95C>G polymorphisms in the IGFBP3 gene may be associated with advanced endometriosis in Korean women.

Laser capture microdissection with genome-wide expression profiling displayed gene expression signatures in endometrioid endometrial cancer

This research determined genes contributing to the pathogenesis of endometrioid endometrial cancer (EEC). Eight pairs of microdissected EEC samples matched with normal glandular epithelium were analyzed using microarray. Unsupervised analysis identified 162 transcripts (58 up- and 104 down-regulated) that were differentially expressed (p < .01, fold change ≥ 1.5) between both groups. Quantitative real-time polymerase chain reaction (qPCR) validated the genes of interest: SLC7A5, SATB1, H19, and ZAK (p < .05). Pathway analysis revealed genes involved in acid amino transport, translation, and chromatin remodeling (p < .05). Laser capture microdissection (LCM) followed by microarray enabled precise assessment of homogeneous cell population and identified putative genes for endometrial carcinogenesis.