Circulating concentrations of insulin-like growth factor-I and risk of breast cancer

Patterns of Infancy Growth and Metabolic Hormonal Profile Are Different in Very-Low-Birth-Weight Preterm Infants Born Small for Gestational Age Compared to Those Born Appropriate for Gestational Age

BACKGROUND/AIMS

An increased preterm birth survival rate is associated with long-term neurological and metabolic risks; thus, our aim was to evaluate whether early patterns of infancy anthropometry and metabolic hormonal profile differ in preterm infants born small for gestational age (SGA) or appropriate for gestational age (AGA) from birth to 36 months of corrected age (CA).

METHODS

We recruited 110 very-low-birth-weight (VLBW) preterm infants (AGA = 60 and SGA = 50) with a mean birth weight of -2.39 ± 0.77 versus 0.57 ± 0.54 standard deviation scores (SDS) (p < 0.01) and birth length of -2.1 ± 1.05 versus -0.44 ± 0.82 SDS (p < 0.01), respectively. Anthropometry and blood sampling for insulin, insulin-like growth factor (IGF)-II, IGF-I, and leptin were performed for up to 3 years.

RESULTS

All neonates increased their weight, length, and head circumference SDS during the early inpatient period. Up to 90% reached a normal length within this period. The IGF-II, insulin, and glycemia concentrations changed in parallel with weight. In the first year of CA, only SGA infants gained weight and height SDS. The homoeostatic model assessment had a trend toward higher values in SGA infants at 24 and 36 months (p = 0.06 and p = 0.07).

CONCLUSION

Being SGA is the strongest predictor of early recovery of height in VLBW preterm infants. Follow-up will allow us to determine whether the differences in the growth patterns of VLBW preterm infants by birth weight SDS persist.

New Insights into the Role of Exercise in Inhibiting mTOR Signaling in Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) does not express estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 and is characterized by its aggressive nature, lack of targets for targeted therapies, and early peak of recurrence. Due to these specific characteristics, chemotherapy does not usually yield substantial improvements and new target therapies and alternative strategies are needed. The beneficial responses of TNBC survivors to regular exercise, including a reduction in the rate of tumor growth, are becoming increasingly apparent. Physiological adaptations to exercise occur in skeletal muscle but have an impact on the entire body through systemic control of energy homeostasis and metabolism, which in turn influence the TNBC tumor microenvironment. Gaining insights into the causal mechanisms of the therapeutic cancer control properties of regular exercise is important to improve the prescription and implementation of exercise and training in TNBC survivors. Here, we provide new evidence of the effects of exercise on TNBC prevention, control, and outcomes, based on the inhibition of the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (PKB also known as Akt)/mammalian target of rapamycin (mTOR) (PI3K-Akt-mTOR) signaling. These findings have wide-ranging clinical implications for cancer treatment, including recurrence and case management.

Expansion of cancer stem cell pool initiates lung cancer recurrence before angiogenesis

Angiogenesis is essential in the early stage of solid tumor recurrence, but how a suspensive tumor is reactivated before angiogenesis is mostly unknown. Herein, we stumble across an interesting phenomenon that s.c. xenografting human lung cancer tissues can awaken the s.c. suspensive tumor in nude mice. We further found that a high level of insulin-like growth factor 1 (IGF1) was mainly responsible for triggering the transition from suspensive tumor to progressive tumor in this model. The s.c. suspensive tumor is characterized with growth arrest, avascularity, and a steady-state level of proliferating and apoptotic cells. Intriguingly, CD133⁺ lung cancer stem cells (LCSCs) are highly enriched in suspensive tumor compared with progressive tumor. Mechanistically, high IGF1 initiates LCSCs self-renewal from asymmetry to symmetry via the activation of a PI3K/Akt/β-catenin axis. Next, the expansion of LCSC pool promotes angiogenesis by increasing the production of CXCL1 and PlGF in CD133⁺ LCSCs, which results in lung cancer recurrence. Clinically, a high level of serum IGF1 in lung cancer patients after orthotopic lung cancer resection as an unfavorable factor is strongly correlated with the high rate of recurrence and indicates an adverse progression-free survival. Vice versa, blocking IGF1 or CXCL1/PlGF with neutralizing antibodies can prevent the reactivation of a suspensive tumor induced by IGF1 stimulation in the mouse model. Collectively, the expansion of LCSC pool before angiogenesis induced by IGF1 is a key checkpoint during the initiation of cancer relapse, and targeting serum IGF1 may be a promising treatment for preventing recurrence in lung cancer patients.

Molecular Signatures of the Insulin-like Growth Factor 1-mediated Epithelial-Mesenchymal Transition in Breast, Lung and Gastric Cancers

The insulin-like growth factor (IGF) system, which is constituted by the IGF-1 and IGF-2 peptide hormones, their corresponding receptors and several IGF binding proteins, is involved in physiological and pathophysiological processes. The IGF system promotes cancer proliferation/survival and its signaling induces the epithelial-mesenchymal transition (EMT) phenotype, which contributes to the migration, invasiveness, and metastasis of epithelial tumors. These cancers share two major IGF-1R signaling transduction pathways, PI3K/AKT and RAS/MEK/ERK. However, as far as we could review at this time, each type of cancer cell undergoes EMT through tumor-specific routes. Here, we review the tumor-specific molecular signatures of IGF-1-mediated EMT in breast, lung, and gastric cancers.

Preclinical and phase I clinical studies of KW-2450, a dual IGF-1R/IR tyrosine kinase inhibitor, in combination with lapatinib and letrozole

Background:

KW-2450 is an oral dual insulin-like growth factor-1 receptor/insulin receptor tyrosine kinase inhibitor. We investigated the in vitro and in vivo preclinical activity of KW-2450 plus lapatinib and letrozole and conducted a phase I trial of the triple-drug combination in one male and 10 postmenopausal female patients with advanced/metastatic hormone receptor-positive, human epidermal growth factor receptor 2 (HER2)-positive breast cancer.

Methods:

A series of in vitro and in vivo animal studies was undertaken of KW-2450 in combination with lapatinib and hormonal agents. The phase I trial was conducted to establish the safety, tolerability, and recommended phase II dose (RP2D) of KW-2450 administered in combination with lapatinib and letrozole.

Results:

Preclinical studies showed KW-2450 and lapatinib act synergistically to induce in vitro apoptosis and inhibit growth of HER2-positive MDA-MB-361 and BT-474 breast cancer cell lines. This combined effect was confirmed in vivo using the MDA-MB-361 xenograft model. KW-2450 showed synergistic in vitro growth inhibition with letrozole and 4-hydroxytamoxifen in ER-positive MCF-7 breast cancer cells and MCF-7-Ac1 aromatase-transfected MCF-7 cells. In the phase I study, dose-limiting toxicity (DLT; grade 3 rash and grade 3 hyperglycemia, respectively) occurred in two of three patients at the dose of KW-2450 25 mg/day plus lapatinib 1500 mg/day and letrozole 2.5 mg/day. The RP2D of the triple-drug combination was established as KW-2450 25 mg/day, lapatinib 1250 mg/day, and letrozole 2.5 mg/day with no DLT at this dose level.

Conclusions:

The proposed phase II study of the RP2D for the triple-drug combination did not progress because of anticipated difficulty in patient enrollment and further clinical development of KW-2450 was terminated.

Growth hormone-releasing hormone (GHRH) and its agonists inhibit hepatic and tumoral secretion of IGF-1

The role of hypothalamic growth hormone-releasing hormone (GHRH) in the release of growth hormone (GH) from the pituitary is well established. However, direct effects of GHRH and its agonistic analogs on extra-pituitary cells and tissues have not been completely elucidated. In the present study, we first demonstrated that human and rat hepatocytes express receptors for GHRH. We then showed that GHRH(1-29)NH 2 and GHRH agonist, MR-409, downregulated mRNA levels for IGF-1 in human cancer cell lines and inhibited IGF-1 secretion in vitro when these cancer lines were exposed to rhGH. Another GHRH agonist, MR-356, lowered serum IGF-l and inhibited tumor growth in nude mice bearing xenografted NCI-N87 human stomach cancers. GHRH(1-29)NH 2 and MR-409 also suppressed the expression of mRNA for IGF-1 and IGF-2 in rat and human hepatocytes, decreased the secretion of IGF-1 in vitro from rat hepatocytes stimulated with rhGH, and lowered serum IGF-l levels in hypophysectomized rats injected with rhGH. Vasoactive intestinal peptide had no effect on the release of IGF-1 from the hepatocytes. Treatment of C57BL/6 mice with MR-409 reduced serum levels of IGF-l from days 1 to 5. These results show that GHRH and its agonists can, by a direct action, inhibit the secretion of IGF-1 from the liver and from tumors. The inhibitory effect of GHRH appears to be mediated by the GHRH receptor (GHRH-R) and GH receptor (GHR), with the involvement of JAK2/STAT5 pathways. Further studies are required to investigate the possible physiopathological role of GHRH in the control of secretion of IGF-1.

β-catenin/TCF activity regulates IGF-1R tyrosine kinase inhibitor sensitivity in colon cancer

The availability of large-scale drug screening data on cell line panels provides a unique opportunity to identify predictive biomarkers for targeted drug efficacy. Analysis of diverse drug data on ~990 cancer cell lines revealed enhanced sensitivity of insulin-like growth factor 1 receptor/ Insulin Receptor (IGF-1R/IR) tyrosine kinase inhibitors (TKIs) in colon cancer cells. Interestingly, β-catenin/TCF(T cell factor)-responsive promoter activity exhibited a significant positive association with IGF-1R/IR TKI response, while the mutational status of direct upstream genes, such as CTNNB1 and APC, was not significantly associated with the response. The β-catenin/TCF activity high cell lines express components of IGF-1R/IR signaling more than the low cell lines explaining their enhanced sensitivity against IGF-1R/IR TKI. Reinforcing β-catenin/TCF responsive promoter activity by introducing CTNNB1 gain-of-function mutations into IGF-1R/IR TKI-resistant cells increased the expression and activity of IGF-1R/IR signaling components and also sensitized the cells to IGF-1R/IR TKIs in vitro and in vivo. Analysis of TCGA data revealed that the stronger β-catenin/TCF responsive promoter activity was associated with higher IGF-1R and IGF2 transcription in human colon cancer specimens as well. Collectively, compared to the mutational status of upstream genes, β-catenin/TCF responsive promoter activity has potential to be a stronger predictive positive biomarker for IGF-1R/IR TKI responses in colon cancer cells. The present study highlights the potential of transcriptional activity as therapeutic biomarkers for targeted therapies, overcoming the limited ability of upstream genetic mutations to predict responses.

Differential expression of IGFBPs in Laron syndrome-derived lymphoblastoid cell lines: Potential correlation with reduced cancer incidence

Laron syndrome (LS), or primary growth hormone (GH) insensitivity, is a growth disorder that results from mutation of the GH-receptor (GHR) gene leading to congenital insulin-like growth factor-1 (IGF-1) deficiency. Recent epidemiological studies have shown that LS patients are protected from cancer development. Genome-wide profiling identified genes and signaling pathways that are differentially represented in LS patients, and that may contribute to cancer protection. The present study was aimed at evaluating the hypothesis that IGF binding proteins (IGFBPs) are differentially expressed in LS, most probably as a result of low circulating levels of IGF-1. Furthermore, we postulated that IGFBPs might be differentially regulated by oxidative stress in this condition and, therefore, may contribute to cancer evasion. Our results show that IGFBP-3, which is predominantly protective, was highly expressed in LS-derived lymphoblastoid cells in comparison to control cells from the same ethnic group. On the other hand, levels of IGFBP-2, -4, -5, and -6 were diminished in LS patients, as demonstrated by RQ-PCR, Western immunoblots and confocal immunofluorescence. In addition, our data provide evidence for a pattern of IGFBP response to H₂O₂ treatment that might be associated with distinct expression of apoptosis markers (BCL2, pro-caspase-9, pro-caspase-3) in LS. In summary, differential expression of specific IGFBPs in LS might be correlated with cellular mechanisms underlying cancer protection and, probably, additional phenotypes due to congenital IGF-1 deficiency.

Blood derivatives awaken in regenerative medicine strategies to modulate wound healing

Blood components play key roles in the modulation of the wound healing process and, together with the provisional fibrin matrix ability to selectively bind bioactive molecules and control its spatial-temporal presentation, define the complex microenvironment that characterize this biological process. As a biomimetic approach, the use of blood derivatives in regenerative strategies has awakened as a source of multiple therapeutic biomolecules. Nevertheless, and despite their clinical relevance, blood derivatives have been showing inconsistent therapeutic results due to several factors, including proper control over their delivery mechanisms. Herein, we highlight recent trends on the use biomaterials to protect, sequester and deliver these pools of biomolecules in tissue engineering and regenerative medicine approaches. Particular emphasis is given to strategies that enable to control their spatiotemporal delivery and improve the selectivity of presentation profiles of the biomolecules derived from blood derivatives rich in platelets. Finally, we discussed possible directions for biomaterials design to potentiate the aimed regenerative effects of blood derivatives and achieve efficient therapies.

The ovarian cancer oncobiome

Humans and other mammals are colonized by microbial agents across the kingdom which can represent a unique microbiome pattern. Dysbiosis of the microbiome has been associated with pathology including cancer. We have identified a microbiome signature unique to ovarian cancers, one of the most lethal malignancies of the female reproductive system, primarily because of its asymptomatic nature during the early stages in development. We screened ovarian cancer samples along with matched, and non-matched control samples using our pan-pathogen array (PathoChip), combined with capture-next generation sequencing. The results show a distinct group of viral, bacterial, fungal and parasitic signatures of high significance in ovarian cases. Further analysis shows specific viral integration sites within the host genome of tumor samples, which may contribute to the carcinogenic process. The ovarian cancer microbiome signature provides insights for the development of targeted therapeutics against ovarian cancers.

Breast cancer risk in relation to history of preeclampsia and hyperemesis gravidarum: Prospective analysis in the Generations Study

Preeclampsia and hyperemesis gravidarum are pregnancy complications associated with altered sex hormone levels. Previous studies suggest preeclampsia may be associated with a decreased risk of subsequent breast cancer and hyperemesis with an increased risk, but the evidence remains unclear. We used data from the Generations Study, a large prospective study of women in the United Kingdom, to estimate relative risks of breast cancer in relation to a history of preeclampsia and hyperemesis using Cox regression adjusting for known breast cancer risk factors. During 7.5 years average follow‐up of 82,053 parous women, 1,969 were diagnosed with invasive or in situ breast cancer. Women who had experienced preeclampsia during pregnancy had a significantly decreased risk of premenopausal breast cancer (hazard ratio (HR) =0.67, 95% confidence interval (CI): 0.49–0.90) and of HER2‐enriched tumours (HR = 0.33, 95% CI: 0.12–0.91), but there was no association with overall (HR = 0.90, 95% CI: 0.80–1.02) or postmenopausal (HR = 0.97, 95% CI: 0.85–1.12) breast cancer risk. Risk reductions among premenopausal women were strongest within 20 years since the last pregnancy with preeclampsia. Hyperemesis was associated with a significantly increased risk of HER2‐enriched tumours (HR = 1.76, 95% CI: 1.07–2.87), but not with other intrinsic subtypes or breast cancer risk overall. These results provide evidence that preeclampsia is associated with a decreased risk of premenopausal and HER2‐enriched breast cancer and that hyperemesis, although not associated with breast cancer risk overall, may be associated with raised risk of HER2‐enriched tumours.

What's new?

Although the link of preeclampsia and hyperemesis gravidarum with altered sex hormone levels is well established, relatively little is known about the association of these pregnancy complications with breast cancer risk. Here, the authors found that a history of preeclampsia decreased the risk of premenopausal breast cancer and tumors enriched for the receptor tyrosine‐protein kinase HER2. In contrast, hyperemesis gravidarum increased the risk to develop HER2‐enriched tumors, pointing to nuanced differences of sex hormone alterations during pregnancy with respect to breast cancer subtypes and menopausal status.

Current perspectives on in vitro maturation and its effects on oocyte genetic and epigenetic profiles

In vitro maturation (IVM), the maturation in culture of immature oocytes, has been used in clinic for more than 20 years. Although IVM has the specific advantages of low cost and minor side effects over controlled ovarian stimulation, the prevalence of IVM is less than 1% of routine in vitro fertilization and embryo transfer techniques in many reproductive centers. In this review, we searched the MEDLINE database for all full texts and/or abstract articles published in English with content related to oocyte IVM mainly between 2000 and 2016. Many different aspects of the IVM method may influence oocyte potential, including priming, gonadotrophin, growth factors, and culture times. The culture conditions of IVM result in alterations in the oocyte or cumulus cell transcriptome that are not observed under in vivo culture conditions. Additionally, epigenetic modifications, such as DNA methylation or acetylation, are also different between in vitro and in vivo cultured oocytes. In sum, current IVM technique is still not popular and requires more systematic and intensive research to improve its effects and applications. This review will help point our problems, supply evidence or clues for future improving IVM technique, thus assist patients for fertility treatment or preservation as an additional option.

A phase 2 study of OSI-906 (linsitinib, an insulin-like growth factor receptor-1 inhibitor) in patients with asymptomatic or mildly symptomatic (non-opioid requiring) metastatic castrate resistant prostate cancer (CRPC)

Background The inhibition of insulin-like growth factor receptor-1 (IGF-1R) induces cell cycle arrest and enhancing the effect of castration by delay of progression of human prostate cancer models. Linsitinib is a small molecule and potent dual inhibitor of IGF-1R and insulin receptor tyrosine kinase activity. We report results of a single-arm, phase II study evaluating the safety and efficacy of linsitinib in men with chemotherapy-naïve asymptomatic or mildly symptomatic metastatic castration resistant prostate cancer (mCRPC). Methods Patients received at 150 mg orally twice daily on a 28-day cycle. The primary endpoint was prostate specific (PSA) response at 12 weeks and correlative studies included circulating tumor cells (CTCs) and circulating endothelial cells (CECs). Results Seventeen patients, median age 68 (55-78) and pre-treatment PSA of 55.23 (2.46-277.60) were enrolled and completed 12 weeks of therapy. All but two patients discontinued therapy secondary to PSA progression, which met the predefined futility criteria and led to early termination of this study. Overall best response (RECIST v1.1) included a partial response in 1 patient and stable disease in 8 patients. Higher baseline CTCs were associated with higher pre-treatment PSA levels (Spearman r = 0.49, p = 0.04) but no correlation between PSA progression and CTCs/CECs were observed. Most common adverse events included fatigue, nausea/vomiting, AST/ALT changes and prolonged QT interval. Conclusions Single-agent linsitinib was safe and well tolerated but failed to show activity in men with mCRPC. These results highlight the complexity of using IGF-1R as a therapeutic target in this patient population. ClinicalTrials.gov NCT01533246.

Lifestyle and Breast Cancer Recurrences: The DIANA-5 Trial

Aims and Background

The DIANA (Diet and Androgens)-5 study is a multi-institutional randomized controlled trial of the effectiveness of a diet based on Mediterranean and macrobiotic recipes and principles, associated with moderate physical activity, in reducing additional breast cancer events in women with early stage invasive breast cancer at high risk of recurrence because of metabolic or endocrine milieu. The intervention is expected to reduce serum insulin and sex hormones, which were associated with breast prognosis in previous studies.

Methods

Between 2008 and 2010, the study randomly assigned 1208 patients to an intensive diet and exercise intervention or to a comparison group, to be followed-up through 2015. General lifestyle recommendations for the prevention of cancer are given to both groups, and the intervention group is being offered a comprehensive lifestyle intervention, including cooking classes, conferences, common meals and exercise sessions. Adherence assessments occurred at baseline and at 12 months and are planned at 36 and 60 months. They include food frequency diaries, anthropometric measures, body fat distribution assessed with impedance scale, one week registration of physical activity with a multisensor arm-band monitor, metabolic and endocrine blood parameters. Outcome breast cancer events are assessed through self report at semi annual meetings or telephone interview and are validated through medical record verification.

Results

The randomized groups were comparable for age (51.8 years), proportion of ER-negative tumors (22%), axillary node metastasis (42%), reproductive variables, tobacco smoking, blood pressure, anthropometric measurements and hormonal and metabolic parameters.

Conclusions

DIANA-5 has the potential to establish whether a Mediterranean-macrobiotic lifestyle may reduce breast cancer recurrences. We will assess evidence of effectiveness, first by comparing the incidence of additional breast cancer events (local or distant recurrence, second ipsilateral or contralateral cancer) in the intervention and in the control group, by an intention-to-treat analysis, and second by analyzing the incidence of breast cancer events in the total study population by compliance assessment score.

Inherited factors contribute to an inverse association between preeclampsia and breast cancer

Background

Preeclampsia is frequently linked to reduced breast cancer risk. However, little is known regarding the underlying genetic association and the association between preeclampsia and mammographic density.

Methods

This study estimates the incidence rate ratios (IRRs) of breast cancer in patients with preeclampsia, when compared to women without preeclampsia, using Poisson regression models in two cohorts of pregnant women: a Swedish nationwide cohort (n = 1,337,934, 1973–2011) and the Karolinska Mammography Project for Risk Prediction of Breast Cancer (KARMA, n = 55,044, 1958–2015). To identify the genetic association between preeclampsia and breast cancer, we used logistic regression models to calculate the odds ratios (ORs) of preeclampsia in sisters of breast cancer patients, and in women with different percentiles of breast cancer polygenic risk scores (PRS). Linear regression models were used to estimate the mammographic density by preeclampsia status in the KARMA cohort.

Results

A decreased risk of breast cancer was observed among patients with preeclampsia in both the nationwide (IRR = 0.90, 95% CI = 0.85; 0.96) and KARMA cohorts (IRR = 0.75, 95% CI = 0.61; 0.93). Women with high breast cancer PRS and sisters of breast cancer patients had a lower risk of preeclampsia (OR = 0.89, 95% CI = 0.83; 0.96). Mammographic density was lower in women with preeclampsia compared to women without preeclampsia (-2.04%, 95% CI = -2.65; -1.43). Additionally, among sisters in the KARMA cohort (N = 3500), density was lower in sisters of patients with preeclampsia compared to sisters of women without preeclampsia (-2.76%, 95% CI = -4.96; -0.56).

Conclusion

Preeclampsia is associated with reduced risk of breast cancer and mammographic density. Inherited factors contribute to this inverse association.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-017-0930-6) contains supplementary material, which is available to authorized users.

Current perspectives between metabolic syndrome and cancer

Metabolic syndrome is a cluster of risk factors that lead to cardiovascular morbidity and mortality. Recent studies linked metabolic syndrome and several types of cancer. Although metabolic syndrome may not necessarily cause cancer, it is linked to poorer cancer outcomes including increased risk of recurrence and overall mortality. This review tends to discuss the major biological and physiological alterations involved in the increase of incidence and mortality of cancer patients affected by metabolic syndrome. We focus on metabolic syndrome-associated visceral adiposity, hyperinsulinemia, hyperglycemia, insulin-like growth factor (IGF-I) pathway as well as estrogen signaling and inflammation. Several of these factors are also involved in carcinogenesis and cancer progression. A better understanding of the link between metabolic syndrome and cancer may provide new insight about oncogenesis. Moreover, prevention of metabolic syndrome - related alterations may be an important aspect in the management of cancer patients during simultaneous palliative care.

Doping and Urologic Tumors

Several substances such as growth hormone (GH), erythropoietin (Epo), and anabolic steroids (AS) are improperly utilized to increase the performance of athletes. Evaluating the potential cancer risk associated with doping agents is difficult since these drugs are often used at very high doses and in combination with other licit or illicit drugs.

The GH, via its mediator, the insulin-like growth factor 1 (IGF-1), is involved in the development and progression of cancer. Animal studies suggested that high levels of GH/IGF-1 increase progression of androgen-independent prostate cancer. Clinical data regarding prostate cancer are mostly based on epidemiological studies or indirect data such as IGF-1 high levels in patients with prostate cancer. Even if experimental studies showed a correlation between Epo and cancer, no clinical data are currently available on cancer development related to Epo as a doping agent. Androgens are involved in prostate carcinogenesis modulating genes that regulate cell proliferation, apoptosis and angiogenesis. Most information on AS is anecdotal (case reports on prostate, kidney and testicular cancers). Prospective epidemiologic studies failed to support the hypothesis that circulating androgens are positively associated with prostate cancer risk.

Currently, clinical and epidemiological studies supporting association between doping and urological neoplasias are not available. Nowadays, exposure to doping agents starts more prematurely with a consequent longer exposition period; drugs are often used at very high doses and in combination with other licit or illicit drugs. Due to all these elements it is impossible to predict all the side effects, including cancer; more detailed studies are therefore necessary.

Identification of thioredoxin-interacting protein (TXNIP) as a downstream target for IGF1 action

Laron syndrome (LS), or primary growth hormone (GH) insensitivity, is the best-characterized entity among the congenital insulin-like growth factor 1 (IGF1) deficiencies. Life-long exposure to minute endogenous IGF1 levels is linked to low stature as well as a number of endocrine and metabolic abnormalities. While elevated IGF1 is correlated with increased cancer incidence, epidemiological studies revealed that patients with LS do not develop tumors. The mechanisms associated with cancer protection in LS are yet to be discovered. Recent genomic analyses identified a series of metabolic genes that are overrepresented in patients with LS. Given the augmented expression of these genes in a low IGF1 milieu, we hypothesized that they may constitute targets for IGF1 action. Thioredoxin-interacting protein (TXNIP) plays a critical role in cellular redox control by thioredoxin. TXNIP serves as a glucose and oxidative stress sensor, being commonly silenced by genetic or epigenetic events in cancer cells. Consistent with its enhanced expression in LS, we provide evidence that TXNIP gene expression is negatively regulated by IGF1. These results were corroborated in animal studies. In addition, we show that oxidative and glucose stresses led to marked increases in TXNIP expression. Supplementation of IGF1 attenuated TXNIP levels, suggesting that IGF1 exerts its antiapoptotic effect via inhibition of TXNIP Augmented TXNIP expression in LS may account for cancer protection in this condition. Finally, TXNIP levels could be potentially useful in the clinic as a predictive or diagnostic biomarker for IGF1R-targeted therapies.

Cardiometabolic risk factors and survival after breast cancer in the Women's Health Initiative

BACKGROUND

Few studies have examined the relationship between cardiometabolic risk factors linked to metabolic syndrome and mortality among women with breast cancer.

METHODS

We used the Women's Health Initiative to evaluate the relationship between cardiometabolic risk factors, including waist circumference (WC), blood pressure, cholesterol level, and presence of type 2 diabetes, and their relation with death from breast cancer, cardiovascular disease (CVD), and other causes among 8641 women with local or regional stage invasive breast cancer. Cox proportional hazards models were used to estimate hazard ratios, and 95% confidence intervals, adjusted for important predictors of survival.

RESULTS

After a median of 11.3 years, there were 2181 total deaths, 619 (28.4%) of which were due to breast cancer. Most participants (55.7%) had at least 2 cardiometabolic risk factors, and 4.9% had 3 or 4. Having a larger number of risk factors was associated with higher risk of CVD and other-cause mortality (P trend < .001 for both), but not with breast cancer mortality (P trend = .86). Increased WC was associated with a higher risk of CVD (hazard ratio [HR], 1.28; 95% confidence interval [CI], 1.05-1.57) and other-cause mortality (HR, 1.32; 95% CI, 1.16-1.49) and only with a small and nonsignificant higher risk of breast cancer mortality (HR, 1.19; 95% CI, 0.93-1.52). The results did not differ in analyses stratified by race, hormone receptor status, or after an analysis of cases diagnosed within 5 years after baseline.

CONCLUSIONS

Among women with early stage breast cancer, cardiometabolic risk factors are significantly associated with cardiovascular and other-cause mortality, but not breast cancer mortality. Cancer 2018;124:1798-807. © 2018 American Cancer Society.

Significant Changes in Circulating Plasma Levels of IGF1 and IGFBP3 after Conventional or Dose-Intensified Adjuvant Treatment of Breast Cancer Patients with one to three Positive Lymph Nodes

The insulin-like growth factor 1 (IGF1) and its binding protein IGFBP3 (insulin-like growth factor binding protein 3) play a pivotal role during the growth and development of tissues. The purpose of this study was to evaluate the influence of anthracycline- and taxane-containing adjuvant chemotherapy in breast cancer patients on the circulating plasma levels of IGF1 and its main binding protein, IGFBP3. This investigation was part of a prospective randomized phase III study in which breast cancer patients were treated with either conventional or dose-intensified adjuvant chemotherapy. The factors were quantified in the plasma of 151 patients with a commercially available sandwich enzyme immunoassay. Before therapy, both parameters were within the normal range in most patients (n=145 and n=144). After therapy, both factors had increased significantly by 29% (IGF1) and 19% (IGFBP3), with the highest increase being observed in the dose-intensified group. Correlations with patient and tumor characteristics revealed a relatively higher increase in both parameters in premenopausal patients, patients with lower-grade tumors, more positive lymph nodes, larger tumor volume, and positive hormone receptor status. No correlation was found with the HER2 expression of the tumors.

Growth Factor Delivery Systems for Tissue Engineering and Regenerative Medicine

Growth factors (GFs) are often a key component in tissue engineering and regenerative medicine approaches. In order to fully exploit the therapeutic potential of GFs, GF delivery vehicles have to meet a number of key design criteria such as providing localized delivery and mimicking the dynamic native GF expression levels and patterns. The use of biomaterials as delivery systems is the most successful strategy for controlled delivery and has been translated into different commercially available systems. However, the risk of side effects remains an issue, which is mainly attributed to insufficient control over the release profile. This book chapter reviews the current strategies, chemistries, materials and delivery vehicles employed to overcome the current limitations associated with GF therapies.

IGF-1-mediated PKM2/β-catenin/miR-152 regulatory circuit in breast cancer

Dysregulation of miRNAs is important in breast cancer initiation and malignant progression. Recently we showed that miR-152 downregulation is associated with breast cancer development, yet the underlying mechanism of miR-152 remains to be well elucidated. In this study, we identified β-catenin as a new direct target of miR-152. MiR-152 inhibited cell proliferation by targeting and inhibiting both β-catenin and PKM2 expression. We found that miR-152 expression sensitized the breast cancer cells to paclitaxel treatment by inhibiting β-catenin and PKM2 expression. Intriguingly, IGF-1 induced β-catenin and PKM2 expression and enhanced β-catenin and PKM2 interaction. Subsequently, IGF-1-induced β-catenin and PKM2 complex translocated into the nucleus, which in turn activated expression of miR-152. These results suggested a regulatory circuit between miR-152, β-catenin and PKM2 in breast cancer. By using human clinical specimens, we also showed that miR-152 expression levels were negatively correlated with β-catenin and PKM2 levels in breast cancer tissues. Our findings provide new insights into a mechanism of miR-152 involved in β-catenin and PKM2 inhibition which would have clinical implication for the cancer development and new treatment option in the future.

Insulin-like growth factor-I induces chemoresistence to docetaxel by inhibiting miR-143 in human prostate cancer

Elevated levels of insulin-like growth factor-I (IGF-I) are associated with carcinogenesis and cancer progression. However, the molecular mechanisms by which IGF-I promotes prostate cancer development remain to be elucidated. Docetaxel chemotherapy is an important therapeutic strategy in many types of human cancers including prostate cancer. In this study, we showed that IGF-I rendered PC-3 and DU145 cells more resistant to docetaxel treatment. IGF-I treatment decreased miR-143 expression, but increased the expression levels of IGF-I receptor (IGF-IR) and insulin receptor substrate 1 (IRS1), direct targets of miR-143. Overexpression of miR-143 abolished IGF-I-induced chemoresistance to docetaxel treatment, decreased expression levels of IGF-I, IRS1, and vascular endothelial growth factor (VEGF) in prostate cancer cell lines. Furthermore, docetaxel treatment significantly inhibited VEGF transcriptional activation, whereas IGF-I treatment induced VEGF transcriptional activation in a dose-dependent manner. Forced expression of IGF-IR and IRS1 cDNAs without the 3’ UTR regions restored miR-143-inhibited VEGF transcriptional activation. Finally, miR-143 inhibited tumor growth and made cells more sensitive to docetaxel treatment for decreasing tumor growth in vivo. Taken together, our data demonstrates that IGF-I induces docetaxel resistance and upregulates IGF-IR and IRS1 expression through miR-143 downregulation, whereas miR-143 acts as a tumor suppressor by targeting its targets IGF-IR and IRS1.

Inhibition of PI3K/Akt/mTOR overcomes cisplatin resistance in the triple negative breast cancer cell line HCC38

Background

Widely established targeted therapies directed at triple negative breast cancer (TNBC) are missing. Classical chemotherapy remains the systemic treatment option. Cisplatin has been tested in TNBC but bears the disadvantage of resistance development. The purpose of this study was to identify resistance mechanisms in cisplatin-resistant TNBC cell lines and select targeted therapies based on these findings.

Methods

The TNBC cell lines HCC38 and MDA-MB231 were subjected to intermittent cisplatin treatment resulting in the 3.5-fold cisplatin-resistant subclone HCC38CisR and the 2.1-fold more resistant MDA-MB231CisR. Activation of pro-survival pathways was explored by immunostaining of phospho-receptor tyrosine kinases. Targeted therapies (NVP-AEW541, lapatinib and NVP-BEZ235) against activated pathways were investigated regarding cancer cell growth and cisplatin sensitivity.

Results

In HCC38CisR and MDA-MB231CisR, phosphorylation of epidermal growth factor receptor (EGFR) and insulin-like growth factor 1 receptor (IGF1R) was observed. In HCC38CisR, treatment with NVP-AEW541 increased potency of lapatinib almost seven-fold, but both compounds could not restore cisplatin sensitivity. However, the dual phosphoinositide 3-kinase (PI3K) and mammalian target of rapamycin (mTOR) inhibitor NVP-BEZ235 acted synergistically with cisplatin in HCC38CisR and fully restored cisplatin sensitivity. Similarly, NVP-BEZ235 increased cisplatin potency in MDA-MB231CisR. Furthermore, NVP-AEW541 in combination with lapatinib restored cisplatin sensitivity in MDA-MB231CisR.

Conclusion

Simultaneous inhibition of EGFR and IGF1R in cisplatin-resistant TNBC cell lines was synergistic regarding inhibition of proliferation and induction of apoptosis. Co-treatment with NVP-BEZ235 or with a combination of NVP-AEW541 and lapatinib restored cisplatin sensitivity and may constitute a targeted treatment option for cisplatin-resistant TNBC.

Electronic supplementary material

The online version of this article (10.1186/s12885-017-3695-5) contains supplementary material, which is available to authorized users.

Protective effects of short-term dietary restriction in surgical stress and chemotherapy

Reduced caloric intake including fasting, as well as the dietary composition or the timing of food intake, impact longevity, likely through a modification in the onset or the severity of chronic aging-related diseases such as cancer. As with pre- and post-operative dietary recommendations, evidence-based nutritional advice from healthcare professionals during and after cancer treatment is often vague or conflicting. We hypothesize that preventive dietary recommendations can help in the context of both chronic cancer treatment efficacy and the avoidance of development of secondary malignancies, as well as in the context of protection from the acute stress of surgery. In this perspective review, we will discuss the latest findings on the potential role of short-term dietary restriction in cancer treatment and improvement of surgical outcome.

Growth Hormone and the Epithelial-to-Mesenchymal Transition

CONTEXT

Previous studies have implicated growth hormone (GH) in the progression of several cancers, including breast, colorectal, and pancreatic. A mechanism by which GH may play this role in cancer is through the induction of the epithelial-to-mesenchymal transition (EMT). During the EMT process, epithelial cells lose their defining phenotypes, causing loss of cellular adhesion and increased cell migration. This review aims to carefully summarize the previous two decades of research that points to GH as an initiator of EMT, in both cancerous and noncancerous tissues.

EVIDENCE ACQUISITION

Sources were collected using PubMed and Google Scholar search engines by using specific GH- and/or EMT-related terms. Identified manuscripts were selected for further analysis based on presentation of GH-induced molecular markers of the EMT process in vivo or in vitro.

EVIDENCE SYNTHESIS

Cellular mechanisms involved in GH-induced EMT are the focus of this review, both in cancerous and noncancerous epithelial cells.

CONCLUSIONS

Our findings suggest that a myriad of molecular mechanisms are induced by GH that cause EMT and may point to potential therapeutic use of GH antagonists or any downregulator of GH action in EMT-related disease.

Randomized phase III trial evaluating the role of weight loss in adjuvant treatment of overweight and obese women with early breast cancer (Alliance A011401): study design

Excess body weight is a poor prognostic factor in women with early breast cancer, but the effect of weight loss on the risk of breast cancer recurrence and mortality in women who are overweight or obese at the time of breast cancer diagnosis has not been evaluated. The Alliance for Clinical Trials in Oncology Breast Cancer Weight Loss trial, also known as A011401, is testing the impact of a telephone-based weight loss program on invasive disease-free survival in 3136 women with a body mass index ≥27 kg/m² who have recently been diagnosed with stage II-III, HER-2 negative breast cancer. Secondary outcomes of the trial include the impact of the weight loss intervention on overall survival, body weight, physical activity, dietary intakes, incidence of comorbidities, serum biomarkers and patient reported outcomes. Participants are randomized 1:1 to a 2-year, telephone-based weight loss intervention or to an education control group. The intervention is delivered through 42 telephone calls, delivered by health coaches based at the Dana-Farber Cancer Institute. Calls are supplemented by an intervention workbook, as well as a number of tools to help facilitate weight loss. Intervention goals include loss of 10% of baseline body weight, achieved through caloric restriction and increased physical activity. This large-scale study testing the impact of purposeful weight loss after cancer diagnosis on the risk of breast cancer recurrence and mortality has the potential to make weight loss programs a standard part of breast cancer treatment.

State of the evidence 2017: an update on the connection between breast cancer and the environment

BACKGROUND

In this review, we examine the continually expanding and increasingly compelling data linking radiation and various chemicals in our environment to the current high incidence of breast cancer. Singly and in combination, these toxicants may have contributed significantly to the increasing rates of breast cancer observed over the past several decades. Exposures early in development from gestation through adolescence and early adulthood are particularly of concern as they re-shape the program of genetic, epigenetic and physiological processes in the developing mammary system, leading to an increased risk for developing breast cancer. In the 8 years since we last published a comprehensive review of the relevant literature, hundreds of new papers have appeared supporting this link, and in this update, the evidence on this topic is more extensive and of better quality than that previously available.

CONCLUSION

Increasing evidence from epidemiological studies, as well as a better understanding of mechanisms linking toxicants with development of breast cancer, all reinforce the conclusion that exposures to these substances - many of which are found in common, everyday products and byproducts - may lead to increased risk of developing breast cancer. Moving forward, attention to methodological limitations, especially in relevant epidemiological and animal models, will need to be addressed to allow clearer and more direct connections to be evaluated.

Identification of B and T cell epitope based peptide vaccine from IGF-1 receptor in breast cancer

The insulin-like growth factor-1 receptor (IGF-1R) plays a key role in proliferation, growth, differentiation, and development of several human malignancies including breast and pancreatic adenocarcinoma. IGF-1R targeted immunotherapeutic approaches are particularly attractive, as they may potentially elicit even stronger antitumor responses than traditional targeted approaches. Cancer peptide vaccines can produce immunologic responses against cancer cells by triggering helper T cell (Th) or cytotoxic T cells (CTL) in association with Major Histocompatibility Complex (MHC) class I or II molecules on the cell surface of antigen presenting cells. In our previous study, we set a technique based on molecular docking in order to find the best MHC class I and II binder peptides using GOLD. In the present work, molecular docking analyses on a library consisting of 30 peptides mimicking discontinuous epitopes from IGF-1R extracellular domain identified peptides 249 and 86, as the best MHC binder peptides to both MHC class I and II molecules. The receptors most often targeted by peptide 249 are HLA-DR4, HLA-DR3 and HLA-DR2 and those most often targeted by peptide 86 are HLA-DR4, HLA-DP2 and HLA-DR3. These findings, based on bioinformatics analyses, can be conducted in further experimental analyses in cancer therapy and vaccine design.

Pubertal development in girls by breast cancer family history: the LEGACY girls cohort

Background

Pubertal milestones, such as onset of breast development and menstruation, play an important role in breast cancer etiology. It is unclear if these milestones are different in girls with a first- or second-degree breast cancer family history (BCFH).

Methods

In the LEGACY Girls Study (n = 1040), we examined whether three mother/guardian-reported pubertal milestones (having reached Tanner Stage 2 or higher (T2+) for breast and pubic hair development, and having started menstruation) differed by BCFH. We also examined whether associations between body size and race/ethnicity and pubertal milestones were modified by BCFH. We used mother/guardian reports as the primary measure of pubertal milestones, but also conducted sensitivity analyses using clinical Tanner measurements available for a subcohort (n = 204). We analyzed cross-sectional baseline data with logistic regression models for the entire cohort, and longitudinal data with Weibull survival models for the subcohort of girls that were aged 5–7 years at baseline (n = 258).

Results

BCFH was modestly, but not statistically significantly, associated with Breast T2+ (odds ratio (OR) = 1.36, 95% confidence interval (CI) = 0.88–2.10), with a stronger association seen in the subcohort of girls with clinical breast Tanner staging (OR = 2.20, 95% CI = 0.91–5.32). In a longitudinal analysis of girls who were aged 5–7 years at baseline, BCFH was associated with a 50% increased rate of having early breast development (hazard ratio (HR) = 1.49, 95% CI = 1.0–2.21). This association increased to twofold in girls who were not overweight at baseline (HR = 2.04, 95% CI = 1.29–3.21). BCFH was not associated with pubic hair development and post-menarche status. The median interval between onset of breast development and menarche was longer for BCFH+ than BCFH– girls (2.3 versus 1.7 years), suggesting a slower developmental tempo for BCFH+ girls. Associations between pubertal milestones and body size and race/ethnicity were similar in girls with or without a BCFH. For example, weight was positively associated with Breast T2+ in both girls with (OR = 1.06 per 1 kg, 95% CI = 1.03–1.10) and without (OR = 1.14 per 1 kg, 95% CI = 1.04–1.24) a BCFH.

Conclusions

These results suggest that BCFH may be related to earlier breast development and slower pubertal tempo independent of body size and race/ethnicity.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-017-0849-y) contains supplementary material, which is available to authorized users.

The effect of growth hormone replacement in patients with hypopituitarism on pituitary tumor recurrence, secondary cancer, and stroke

Growth hormone replacement therapy has benefits for patients with hypopituitarism. The safety profile in regard to tumor recurrence or progression, development of secondary malignancies, or cerebrovascular stroke is still an area of debate. A comprehensive search of multiple databases-MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus was conducted through August 2015. Eligible studies that evaluated long-term adverse events in adult patients with hypopituitarism treated with growth hormone replacement therapy and reported development of pituitary tumor recurrence or progression, secondary malignancies, or cerebrovascular stroke were selected following a predefined protocol. Reviewers, independently and in duplicate, extracted data and assessed the risk of bias. Random-effects meta-analysis was used to pool relative risks and 95 % confidence intervals. We included 15 studies (published 1995-2015) that reported on 46,148 patients. Compared to non-replacement, growth hormone replacement therapy in adults with hypopituitarism was not associated with statistically significant change in pituitary tumor progression or recurrence (relative risk, 0.77; 95 % confidence interval, 0.53-1.13) or development of secondary malignancy (relative risk, 0.99; 95 % confidence interval, 0.70-1.39). In two retrospective studies, there was higher risk of stroke in patients who did not receive replacement (relative risk, 2.07; 95 % confidence interval, 1.51-2.83). The quality of evidence is low due to study limitations and imprecision. This systematic review and meta-analysis supports the overall safety of growth hormone therapeutic use in adults with hypopituitarism with no clear evidence of increased risk of pituitary tumor recurrence, malignancy, or stroke.

Does soy protein affect circulating levels of unbound IGF-1?

INTRODUCTION

Despite the enormous amount of research that has been conducted on the role of soyfoods in the prevention and treatment of chronic disease, the mechanisms by which soy exerts its physiological effects are not fully understood. The clinical data show that neither soyfoods nor soy protein nor isoflavones affect circulating levels of reproductive hormones in men or women. However, some research suggests that soy protein, but not isoflavones, affects insulin-like growth factor I (IGF-1).

METHODS

Since IGF-1 may have wide-ranging physiological effects, we sought to determine the effect of soy protein on IGF-1 and its major binding protein insulin-like growth factor-binding protein (IGFBP-3). Six clinical studies were identified that compared soy protein with a control protein, albeit only two studies measured IGFBP-3 in addition to IGF-1.

RESULTS

Although the data are difficult to interpret because of the different experimental designs employed, there is some evidence that large amounts of soy protein (>25 g/day) modestly increase IGF-1 levels above levels observed with the control protein.

CONCLUSION

The clinical data suggest that a decision to incorporate soy into the diet should not be based on its possible effects on IGF-1.

Mechanisms of resistance to selective estrogen receptor down-regulator in metastatic breast cancer

Based on the prominent role estrogen receptor (ER) plays in breast cancer, endocrine therapy has been developed to block the ER pathway and has shown great effectiveness. Fulvestrant, the first selective ER down-regulator (SERD), was demonstrated to completely suppress ERα and notably efficient. However, resistance to fulvestrant occurs, either intrinsic or acquired during the treatment. Several potential mechanisms inducing fulvestrant resistance have been proposed, composed of activated ERα-independent compensatory growth factor signaling, stimulated downstream kinases, altered cell cycle mediators, etcetera. Experimentally, combinations of fulvestrant with targeted treatments were reported to eliminate the resistance and improve the effect of fulvestrant. Meanwhile, some clinical trials associated with the targeted combination therapies are in progress. This review focuses on the underlying mechanisms that contribute to fulvestrant resistance in ER-positive breast cancer and provides an overview of combined fulvestrant with targeted agents to shed light on optimal therapies for patients with ER-positive breast cancer.

Insulin-like growth factor 1 gene polymorphism in women with breast cancer

Breast cancer is a disease of unknown etiology; however, the major risk factors are genetic alterations. Studies have demonstrated an association between insulin-like growth factor 1 (IGF-1) gene polymorphism and cell proliferation and reduced apoptosis, in addition to its role in breast cancer growth and aggressiveness. Two polymorphic variants of the IGF-1 gene are highlighted in association with breast cancer, rs6220 and rs7136446, although controversy exists as to this relationship. The current study included 137 women (68 breast cancer cases and 69 controls without breast cancer) who had 3 ml of peripheral blood drawn for the study of genomic DNA extracted from leukocytes using the genotyping technique by real-time polymerase chain reaction. The CC genotype (rs7136446) was present in 4 women (5.9%) from the case group and in 2 (3.0%) women from the control group (p = 0.67), while the GG genotype (rs6220) occurred in 8 (11.5%) women from the case group and in 5 (7.2%) women from the control group (p = 0.75). No statistically significant difference was observed between the CC genotype of variant rs7136446 in premenopausal case and control women (p = 0.31), thus as there was also no significant difference between case and control postmenopausal women (p = 1.00). Concerning the GG genotype of rs6220, it occurred in 6 (14.2%) premenopausal case and 4 (8%) control women (p = 0.71) and no difference was found in postmenopausal women (p = 1.00). In the current study, IGF-1 gene polymorphism of SNP variants rs6220 and rs7136446 had no statistically significant association with breast cancer, both in premenopausal and postmenopausal women.

Influence of The -202 A/C insulin-like growth factor-binding protein-3 promoter polymorphism on individual variation in height in Korean girls

PURPOSE

The most common single nucleotide polymorphism in the IGFBP3 promoter region occurs at position -202. This polymorphic variation occurs frequently and may influence growth hormone responsiveness and somatic growth. However, the effects of IGFBP3 promoter polymorphism on growth in children are unknown.

METHODS

Restriction fragment length polymorphism-based genotyping of the -202 single nucleotide polymorphism was performed in 146 Korean girls aged between 15 and 16 years, who were selected randomly from the Seoul School Health Promotion Center. The participants were divided into 3 groups (tall, medium, and short) according to the height percentile established from normal reference values for Korean children. The serum levels of insulin-like growth factor I (IGF-I) and IGF-binding protein-3 (IGFBP-3) were then compared according to genotype.

RESULTS

The genotype distribution in the participants was 79 AA (54.1%), 60 AC (41.1%), and 7 CC (4.8%). The C allele frequency at the -202 IGFBP3 position was 25.4% in this group. The mean serum IGFBP-3 concentration in girls with the AA genotype was higher than that in girls with the AC genotype in the medium (P=0.047) and short (P=0.035) groups, respectively. There was no difference in the IGF-I to IGFBP-3 molar ratio between the AA and AC genotype groups (P=0.161).

CONCLUSION

In conclusion, the -202 polymorphism in the IGFBP3 promoter region is assumed to affect the serum concentration of IGFBP-3 in children as well as in adults. However, it is unclear whether this affects physical development according to the concentration of IGFBP-3.

IGF-IR signaling in epithelial to mesenchymal transition and targeting IGF-IR therapy: overview and new insights

The insulin-like growth factor-I (IGF-I) signaling induces epithelial to mesenchymal transition (EMT) program and contributes to metastasis and drug resistance in several subtypes of tumors. In preclinical studies, targeting of the insulin-like growth factor-I receptor (IGF-IR) showed promising anti-tumor effects. Unfortunately, high expectations for anti-IGF-IR therapy encountered challenge and disappointment in numerous clinical trials. This review summarizes the regulation of EMT by IGF-I/IGF-IR signaling pathway and drug resistance mechanisms of targeting IGF-IR therapy. Most importantly, we address several factors in the regulation of IGF-I/IGF-IR-associated EMT progression that may be potential predictive biomarkers in targeted therapy.

Validation of a Modified Child-Turcotte-Pugh Classification System Utilizing Insulin-Like Growth Factor-1 for Patients with Hepatocellular Carcinoma in an HBV Endemic Area

BACKGROUND

Recently, a modified insulin-like growth factor-1 (IGF)-Child-Turcotte-Pugh (CTP) classification was proposed to improve the original CTP classification. This study aimed to validate the new IGF-CTP classification system as a prognostic maker for patients with hepatocellular carcinoma (HCC) in a hepatitis B virus endemic area.

METHODS

We conducted a post-hoc analysis of a prospective cohort study. We used Harrell's C-index and U-statistics to compare the prognostic performance of both IGF-CTP and CTP classifications for overall survival. We evaluated the relationship between HCC stage and the four components of the IGF-CTP classification (serum levels of IGF-1, albumin, and total bilirubin and prothrombin time [PT]) using nonparametric trend analysis.

RESULTS

We included a total of 393 patients in this study. In all, 55 patients died during the median follow-up of 59.1 months. There was a difference between IGF-CTP class and CTP class in 14% of patients. Overall, the IGF-CTP classification system had a higher prognostic value (C-index = 0.604, 95% confidence interval [CI] = 0.539-0.668) than the CTP system (C-index = 0.558, 95% CI = 0.501-0.614), but the difference was not statistically significant (P = .07 by U-statistics). A lower serum level of IGF-1 was related to a more advanced cancer stage (P < .01). The remaining components of the IGF-CTP classification were not significantly related to tumor stage (P = .11 for total bilirubin; P = .33 for albumin; and P = .39 for PT).

CONCLUSIONS

The IGF-CTP classification was slightly better than the original CTP classification for predicting survival of patients with HCC in a chronic hepatitis B endemic area. This is most likely due to the fact that serum IGF-1 levels reflect underlying HCC status.

Mammographic Breast Density and Breast Cancer Risk: Implications of the Breast Density Legislation for Health Care Practitioners

Breast density has emerged as a critical phenotypic marker of increased breast cancer risk. The breast density legislation, passed in multiple states, requires patient notification of the implications of the breast density on breast cancer risk and screening. Supplemental screening may be suggested in the state regulation; however, there are limited data to guide conversations with patients. This article will review the current state of supplemental screening in women with dense breasts and discuss theories of the mechanism of action. Guidance is provided to assist in shared decision making and appropriate patient counseling.

Metabolic Syndrome and Breast Cancer Risk

Objective

The study was meant to estimate the prevalence of metabolic syndrome in patients with breast cancer and to establish its role as an independent risk factor on occurrence of breast cancer.

Materials and Methods

Fifty women aged between 40 and 80 years with breast cancer and fifty controls of similar age were assessed for metabolic syndrome prevalence and breast cancer risk factors, including age at menarche, reproductive status, live births, breastfeeding, and family history of breast cancer, age at diagnosis of breast cancer, body mass index, and metabolic syndrome parameters.

Results

Metabolic syndrome prevalence was found in 40.0% of breast cancer patients, and 18.0% of those in control group (P = 0.02). An independent and positive association was seen between metabolic syndrome and breast cancer risk (odds ratio = 3.037; 95% confidence interval 1.214-7.597).

Conclusions

Metabolic syndrome is more prevalent in breast cancer patients and is an independent risk factor for breast cancer.

Genetic ancestry in relation to the metabolic response to a US versus traditional Mexican diet: a randomized crossover feeding trial among women of Mexican descent

BACKGROUND/OBJECTIVES

Certain populations with a large proportion of indigenous American (IA) genetic ancestry may be evolutionarily adapted to traditional diets high in legumes and complex carbohydrates, and may have a detrimental metabolic response to US diets high in refined carbohydrates and added sugars. We tested whether IA ancestry modified the metabolic response to a US versus traditional Mexican diet in a controlled dietary intervention.

SUBJECTS/METHODS

First and second generation Mexican immigrant women (n=53) completed a randomized crossover feeding trial testing the effects of a US versus traditional Mexican diet. The metabolic response to the diets was measured by fasting serum concentrations of glucose, insulin, insulin-like growth factor-1 (IGF-1), IGF-binding protein-3 (IGFBP-3), adiponectin, C-reactive protein, interleukin-6 and computed homeostasis model assessment for insulin resistance (HOMA_IR). Blood collected at baseline was used for genotyping, and estimation of African, European and IA ancestries with the use of 214 ancestry informative markers.

RESULTS

The genetic ancestral background was 56% IA, 38% European and 6% African. Women in the highest IA ancestry tertile (>62%) were shorter in height, less educated and less acculturated to the US lifestyle, and tended to have higher waist-to-hip ratio compared with women in the middle and lowest IA ancestry tertiles, respectively. Compared with the US diet, the traditional Mexican diet tended to reduce glucose, insulin, IGF-1, IGFBP-3 and HOMA_IR among women in the middle IA ancestry group (IA ancestry ⩽45-62%), whereas having no effect on biomarkers related to inflammation.

CONCLUSIONS

We observed modest interactions between IA ancestry and the metabolic response to a US versus traditional Mexican diet among Mexican immigrant women.

Flaxseed Alone or in Combination with Tamoxifen Inhibits MCF-7 Breast Tumor Growth in Ovariectomized Athymic Mice with High Circulating Levels of Estrogen

Flaxseed (FS) is rich in mammalian lignan precursors and α-linolenic acid, which have been suggested as having anticancer effects. Previous studies have shown that 10% FS inhibits the growth of human estrogen–dependent breast cancer (MCF-7) in athymic mice, and it enhances the inhibitory effect of tamoxifen (TAM). This study determined whether the effect of FS, alone or in combination with TAM, is dose dependent, and it explored the potential mechanism of action. Ovariectomized athymic mice with estradiol (E2) supplementation (1.7 mg/pellet, 60-day release) and established MCF-7 tumors were treated with basal diet control (0FS), 5% FS (5FS), 10% FS (10FS), and TAM (TAM/ 0FS; 5 mg/pellet, 60-day release), alone or in combination (TAM/ 5FS and TAM/10FS) for 8 weeks. Compared with control, 5FS and 10FS significantly inhibited tumor growth by 26% and 38%, respectively. TAM/0FS had an effect similar to the 10FS. TAM/ 5FS and TAM/10FS, respectively, induced significant 48% and 43% reductions in tumor size compared with 0FS, and 18% and 10% reductions compared with TAM/0FS. The relative uterine weight was significantly lower in all TAM groups compared with the control. The reduction of tumor growth resulted from decreased cell proliferation and increased cell apoptosis. TAM/ 5FS caused a significantly higher expression of estrogen receptor-α (ERα) compared with 5FS and TAM/0FS, whereas TAM/10FS had a higher ERα than 10FS and TAM/0FS. Compared with the control, progesterone receptor (PgR) expression was significantly reduced in all treatment groups, but insulin-like growth factor-1 (IGF-1) expression was reduced only by 10FS, TAM/5FS and TAM/10FS. Tumor cell proliferation was significantly positively associated with expression of PgR and IGF-1 and negatively associated with apoptosis and ERα. Apoptosis was only associated with ERα. In conclusion, FS inhibited MCF-7 tumor growth in a dose-dependent manner and enhanced the inhibitory effect of TAM due to the modulation of ER and growth factor signal transduction pathways.

Is there a role for IGF-1 in the development of second primary cancers?

Cancer survival rates are increasing, and as a result, more cancer survivors are exposed to the risk of developing a second primary cancer (SPC). It has been hypothesized that one of the underlying mechanisms for this risk could be mediated by variations in insulin-like growth factor-1 (IGF-1). This review summarizes the current epidemiological evidence to identify whether IGF-1 plays a role in the development of SPCs. IGF-1 is known to promote cancer development by inhibiting apoptosis and stimulating cell proliferation. Epidemiological studies have reported a positive association between circulating IGF-1 levels and various primary cancers, such as breast, colorectal, and prostate cancer. The role of IGF-1 in increasing SPC risk has been explored less. Nonetheless, several experimental studies have observed a deregulation of the IGF-1 pathway, which may explain the association between IGF-1 and SPCs. Thus, measuring serum IGF-1 may serve as a useful marker in assessing the risk of SPCs, and therefore, more translational experimental and epidemiological studies are needed to further disentangle the role of IGF-1 in the development of specific SPCs.

Potential Mechanisms underlying the Protective Effect of Pregnancy against Breast Cancer: A Focus on the IGF Pathway

A first full-term birth at an early age protects women against breast cancer by reducing lifetime risk by up to 50%. The underlying mechanism resulting in this protective effect remains unclear, but many avenues have been investigated, including lobular differentiation, cell fate, and stromal composition. A single pregnancy at an early age protects women for 30-40 years, and this long-term protection is likely regulated by a relatively stable yet still modifiable method, such as epigenetic reprograming. Long-lasting epigenetic modifications have been shown to be induced by pregnancy and to target the IGF pathway. Understanding how an early first full-term pregnancy protects against breast cancer and the role of epigenetic reprograming of the IGF system may aid in developing new preventative strategies for young healthy women in the future.

Genetic variation in the insulin, insulin-like growth factor, growth hormone, and leptin pathways in relation to breast cancer in African-American women: the AMBER consortium

The insulin/insulin-like growth factor (IGF) system and related pathways such as growth hormone, and leptin signaling have a key role in cancer development. It is unclear how germline variation in these pathways affects breast cancer risk. We conducted gene-based analyses of 184 genes in the insulin/IGF, growth hormone, and leptin pathways to identify genetic variation associated with risk of breast cancer overall, and for estrogen receptor (ER) subtypes. Tag single-nucleotide polymorphisms (SNPs) for each gene were selected and genotyped on a customized Illumina SNP array. Imputation was carried out using 1000 Genomes haplotypes. The analysis included 91,627 SNPs genotyped or imputed in 3,663 breast cancer cases, (1,983 ER-positive and 1,098 ER-negative) and 4,687 controls from the African American Breast Cancer Epidemiology and Risk consortium, a collaborative project of four large studies of breast cancer in African-American women (Carolina Breast Cancer Study, Black Women's Health Study, Women's Circle of Health Study, and Multiethnic Cohort). We used a multi-locus adaptive joint test to determine the association of each gene with overall breast cancer and ER subtypes. The most significant gene associations (P⩽0.01) were BAIAP2 and CALM2 for overall breast cancer; BAIAP2 and CSNK2A1 for ER⁺ breast cancer; and BRAF, BAD, and MAPK3 for ER⁻ breast cancer. The association of BAD with ER⁻ breast cancer was explained by a two-SNP risk model; all other associations were best explained by one-SNP risk models. In total, six genes and seven SNPs had suggestive associations with overall breast cancer or ER subtypes in African-American women.

Insulin-like growth factor-related components and the risk of liver cancer in a nested case-control study

Insulin-like growth factor-1 (IGF1) is a potent mitogen. IGF-binding protein-3 (IGFBP3) binds and inhibits IGF1. High circulating IGF1 levels and low IGFBP3 levels are associated with increased risk of several cancers. We examined relationships between serum levels of these factors and hepatoma risk in a case-control study nested in a prospective cohort study (the Japan Collaborative Cohort Study (JACC Study)). A baseline survey was conducted from 1988 to 1990, and 39,242 subjects donated blood samples. Participants diagnosed with hepatoma by 1997 were considered cases for nested case-control studies. Ninety-one cases and 263 sex- and age-matched controls were analyzed. A conditional logistic model was used to estimate odds ratios (ORs) for the incidence of hepatoma associated with serum IGF1 and IGFBP3 levels. Neither IGF1 nor the molar ratio of IGF1/IGFBP3 was correlated with hepatoma risk. After adjustment for hepatitis viral infection, body mass index, smoking, and alcohol intake, a higher molar difference of (IGFBP3 - IGF1) was associated with a decreased hepatoma risk more than IGFBP3 alone (p for trend <0.001 and = 0.003, respectively). People in the highest quartile had a lower risk (OR = 0.098; 95 % confidence interval = 0.026-0.368). In subgroup analyses of males and females, the molar difference was associated with a decreased hepatoma risk (p for trend <0.05). In non-elderly individuals, the difference was inversely correlated with the incidence of hepatoma (p for trend <0.01). The molar difference of (IGFBP3 - IGF1) may be inversely associated with the incidence of hepatoma.

Mammographic density and breast cancer risk: a mediation analysis

BACKGROUND

High mammographic density (MD) is a strong risk factor for breast cancer. However, it is unclear whether high MD is an intermediate phenotype or whether breast cancer risk factors influence breast cancer risk and MD independently.

METHODS

Our study population included 1290 invasive breast cancer cases and 3422 controls from the Nurses' Health Studies. We estimated the percent of the total association between the risk factor and breast cancer that was mediated by MD.

RESULTS

In both pre- and postmenopausal women, the association between history of biopsy-confirmed benign breast disease and risk was partially mediated by percent MD (percent mediated (PM) = 17 %, p < 0.01 and PM = 33 %, p = 0.04, respectively). In premenopausal women, the associations between early life body size (adolescent somatotype and BMI at age 18) and breast cancer risk were substantially mediated by percent MD (PM = 73 %, p = 0.05 and PM = 82 %, p = 0.04, respectively). In postmenopausal women, the proportion of the associations of childhood somatotype and adolescent somatotype that were mediated by percent MD were lower (PM = 26 %, p = 0.01 for both measures). Hormone therapy use at mammogram was significantly mediated by percent MD in postmenopausal women (PM = 22 %, p < 0.01). Associations with other risk factors, such as age at menarche or family history of breast cancer, were not mediated by percent MD.

CONCLUSIONS

Percent MD partially mediated some of the associations between risk factors and breast cancer, though the magnitude varied by risk factor and menopausal status. These findings suggest that high MD may be an intermediate in some biological pathways for breast cancer development.

Clinical studies in humans targeting the various components of the IGF system show lack of efficacy in the treatment of cancer

The insulin-like growth factors (IGFs) system regulates cell growth, differentiation and energy metabolism and plays crucial role in the regulation of key aspects of tumor biology, such as cancer cell growth, survival, transformation and invasion. The current focus for cancer therapeutic approaches have shifted from the conventional treatments towards the targeted therapies and the IGF system has gained a great interest as anti-cancer therapy. The proliferative, anti-apoptotic and transformation effects of IGFs are mainly triggered by the ligation of the type I IGF receptor (IGF-IR). Thus, aiming at developing novel and effective cancer therapies, different strategies have been employed to target IGF system in human malignancies, including but not limited to ligand or receptor neutralizing antibodies and IGF-IR signaling inhibitors. In this review, we have focused on the clinical studies that have been conducted targeting the various components of the IGF system for the treatment of different types of cancer, providing a description and the challenges of each targeting strategy and the degree of success.