Insulin-like growth factor binding protein 7 mediates glioma cell growth and migration. Neoplasia. 2008;10:1335-1342. [PMID: 19048112 DOI: 10.1593/neo.08694]

Improving iPSC Differentiation Using a Nanodot Platform

Differentiation of induced pluripotent stem cells (iPSCs) is an extremely complex process that has proven difficult to study. In this research, we utilized nanotopography to elucidate details regarding iPSC differentiation by developing a nanodot platform consisting of nanodot arrays of increasing diameter. Subjecting iPSCs cultured on the nanodot platform to a cardiomyocyte (CM) differentiation protocol revealed several significant gene expression profiles that were associated with poor differentiation. The observed expression trends were used to select existing small-molecule drugs capable of modulating differentiation efficiency. BRD K98 was repurposed to inhibit CM differentiation, while iPSCs treated with NSC-663284, carmofur, and KPT-330 all exhibited significant increases in not only CM marker expression but also spontaneous beating, suggesting improved CM differentiation. In addition, quantitative polymerase chain reaction was performed to determine the gene regulation responsible for modulating differentiation efficiency. Multiple genes involved in extracellular matrix remodeling were correlated with a CM differentiation efficiency, while genes involved in the cell cycle exhibited contrasting expression trends that warrant further studies. The results suggest that expression profiles determined via short time-series expression miner analysis of nanodot-cultured iPSC differentiation can not only reveal drugs capable of enhancing differentiation efficiency but also highlight crucial sets of genes related to processes such as extracellular matrix remodeling and the cell cycle that can be targeted for further investigation. Our findings confirm that the nanodot platform can be used to reveal complex mechanisms behind iPSC differentiation and could be an indispensable tool for optimizing iPSC technology for clinical applications.

Insulin-like growth factor-binding protein 7 (IGFBP7): A microenvironment-dependent regulator of angiogenesis and vascular remodeling

Insulin-like Growth Factor-Binding Protein 7 (IGFBP7) is an extracellular matrix (ECM) glycoprotein, highly enriched in activated vasculature during development, physiological and pathological tissue remodeling. Despite decades of research, its role in tissue (re-)vascularization is highly ambiguous, exhibiting pro- and anti-angiogenic properties in different tissue remodeling states. IGFBP7 has multiple binding partners, including structural ECM components, cytokines, chemokines, as well as several receptors. Based on current evidence, it is suggested that IGFBP7's bioactivity is strongly dependent on the microenvironment it is embedded in. Current studies indicate that during physiological angiogenesis, IGFBP7 promotes endothelial cell attachment, luminogenesis, vessel stabilization and maturation. Its effects on other stages of angiogenesis and vessel function remain to be determined. IGFBP7 also modulates the pro-angiogenic properties of other signaling factors, such as VEGF-A and IGF, and potentially acts as a growth factor reservoir, while its actual effects on the factors' signaling may depend on the environment IGFBP7 is embedded in. Besides (re-)vascularization, IGFBP7 clearly promotes progenitor and stem cell commitment and may exhibit anti-inflammatory and anti-fibrotic properties. Nonetheless, its role in inflammation, immunomodulation, fibrosis and cellular senescence is again likely to be context-dependent. Future studies are required to shed more light on the intricate functioning of IGFBP7.

IGFBP7 promotes endothelial cell repair in the recovery phase of acute lung injury

IGFBP7 has been found to play an important role in inflammatory diseases, such as acute lung injury (ALI). However, the role of IGFBP7 in different stages of inflammation remains unclear. Transcriptome sequencing was used to identify the regulatory genes of IGFBP7, and endothelial IGFBP7 expression was knocked down using Aplnr-Dre mice to evaluate the endothelial proliferation capacity. The expression of proliferation-related genes was detected by Western blotting and RT-PCR assays. In the present study, we found that knockdown of IGFBP7 in endothelial cells significantly decreases the expression of endothelial cell proliferation-related genes and cell number in the recovery phase but not in the acute phase of ALI. Mechanistically, using bulk-RNA sequencing and CO-IP, we found that IGFBP7 promotes phosphorylation of FOS and subsequently up-regulates YAP1 molecules, thereby promoting endothelial cell proliferation. This study indicated that IGFBP7 has diverse roles in different stages of ALI, which extends the understanding of IGFBP7 in different stages of ALI and suggests that IGFBP7 as a potential therapeutic target in ALI needs to take into account the period specificity of ALI.

Insulin-like growth factor family and prostate cancer: new insights and emerging opportunities

Prostate cancer is the second most commonly diagnosed cancer in men. The mammalian insulin-like growth factor (IGF) family is made up of three ligands (IGF-I, IGF-II, and insulin), three receptors (IGF-I receptor (IGF-1R), insulin receptor (IR), and IGF-II receptor (IGF-2R)), and six IGF-binding proteins (IGFBPs). IGF-I and IGF-II were identified as potent mitogens and were previously associated with an increased risk of cancer development including prostate cancer. Several reports showed controversy about the expression of the IGF family and their connection to prostate cancer risk due to the high degree of heterogeneity among prostate tumors, sampling bias, and evaluation techniques. Despite that, it is clear that several IGF family members play a role in prostate cancer development, metastasis, and androgen-independent progression. In this review, we aim to expand our understanding of prostate tumorigenesis and regulation through the IGF system. Further understanding of the role of IGF signaling in PCa shows promise and needs to be considered in the context of a comprehensive treatment strategy.

Molecular landscapes of glioblastoma cell lines revealed a group of patients that do not benefit from WWOX tumor suppressor expression

Introduction

Glioblastoma (GBM) is notorious for its clinical and molecular heterogeneity, contributing to therapeutic failure and a grim prognosis. WWOX is one of the tumor suppressor genes important in nervous tissue or related pathologies, which was scarcely investigated in GBM for reliable associations with prognosis or disease progression despite known alterations. Recently, we observed a phenotypic heterogeneity between GBM cell lines (U87MG, T98G, U251MG, DBTRG-05MG), among which the anti-GBM activity of WWOX was generally corresponding, but colony growth and formation were inconsistent in DBTRG-05MG. This prompted us to investigate the molecular landscapes of these cell lines, intending to translate them into the clinical context.

Methods

U87MG/T98G/U251MG/DBTRG-05MG were subjected to high-throughput sequencing, and obtained data were explored via weighted gene co-expression network analysis, differential expression analysis, functional annotation, and network building. Following the identification of the most relevant DBTRG-distinguishing driver genes, data from GBM patients were employed for, e.g., differential expression analysis, survival analysis, and principal component analysis.

Results

Although most driver genes were unique for each cell line, some were inversely regulated in DBTRG-05MG. Alongside driver genes, the differentially-expressed genes were used to build a WWOX-related network depicting protein-protein interactions in U87MG/T98G/U251MG/DBTRG-05MG. This network revealed processes distinctly regulated in DBTRG-05MG, e.g., microglia proliferation or neurofibrillary tangle assembly. POLE4 and HSF2BP were selected as DBTRG-discriminating driver genes based on the gene significance, module membership, and fold-change. Alongside WWOX, POLE4 and HSF2BP expression was used to stratify patients into cell lines-resembling groups that differed in, e.g., prognosis and treatment response. Some differences from a WWOX-related network were certified in patients, revealing genes that clarify clinical outcomes. Presumably, WWOX overexpression in DBTRG-05MG resulted in expression profile change resembling that of patients with inferior prognosis and drug response. Among these patients, WWOX may be inaccessible for its partners and does not manifest its anti-cancer activity, which was proposed in the literature but not regarding glioblastoma or concerning POLE4 and HSF2BP.

Conclusion

Cell lines data enabled the identification of patients among which, despite high expression of WWOX tumor suppressor, no advantageous outcomes were noted due to the cancer-promoting profile ensured by other genes.

Cancer invasion and metastasis: Insights from murine pubertal mammary gland morphogenesis

Cancer invasion and metastasis accounts for the majority of cancer related mortality. A better understanding of the players that drive the aberrant invasion and migration of tumors cells will provide critical targets to inhibit metastasis. Postnatal pubertal mammary gland morphogenesis is characterized by highly proliferative, invasive, and migratory normal epithelial cells. Identifying the molecular regulators of pubertal gland development is a promising strategy since tumorigenesis and metastasis is postulated to be a consequence of aberrant reactivation of developmental stages. In this review, we summarize the pubertal morphogenesis regulators that are involved in cancer metastasis and revisit pubertal mammary gland transcriptome profiling to uncover both known and unknown metastasis genes. Our updated list of pubertal morphogenesis regulators shows that most are implicated in invasion and metastasis. This review highlights molecular linkages between development and metastasis and provides a guide for exploring novel metastatic drivers.

Co-amplified with PDGFRA, IGFBP7 is a prognostic biomarker correlated with the immune infiltrations of glioma

BACKGROUND

A subgroup of glioma carry genetic 4q12 amplification including platelet derived growth factor receptor α (PDGFRA) and insulin like growth factor binding protein 7 (IGFBP7). However, the prognosis of PDGFRA and IGFBP7 in glioma is unclear.

METHODS

The prognosis of PDGFRA and IGFBP7 was determined using cox regression and Kaplan-Meier survival analysis. Pathways associated with IGFBP7 were analyzed through gene set enrichment analysis (GSEA). Immune profiling of glioma was determined using "ESTIMATE" and "TIMER" database.

RESULTS

PDGFRA amplification or expression was not correlated with the outcomes of glioblastoma (GBM). IGFBP7 but not PDGFRA was over-expressed in GBM. IGFBP7 over-expression was correlated with the unfavorable outcomes of GBM. In lower grade glioma (LGG), PDGFRA over-expression was not correlated with the unfavorable prognosis of LGG, while, IGFBP7 was a prognostic biomarker of LGG. LGG patients with IGFBP7 lower expressions had prolonged clinical overall survival. Combination of IDH mutation, LGG grade and IGFBP7 achieved even better prognostic effects in LGG. Moreover, IGFBP7 was over-expressed in glioma patients with wild type IDH or with high grades. IGFBP7 over-expression was correlated with the unfavorable outcomes of glioma. Furthermore, IGFBP7 was hypo-methylated in GBM or LGG patients without IDH mutations. IGFBP7 hyper-methylation was correlated with the lower overall survival of GBM or LGG. LGG patients with wild type IDH and with IGFBP7 hypo-methylation demonstrated even worse prognosis. IGFBP7 was associated with multiple immune-related signaling pathways in GBM or LGG. The stromal score, immune score and the infiltrations of immune cells were also correlated with IGFBP7 and the prognosis of LGG.

CONCLUSIONS

IGFBP7 but not PDGFRA served an ideal prognostic marker and therapeutic target of glioma.

Fam20C Overexpression Predicts Poor Outcomes and is a Diagnostic Biomarker in Lower-Grade Glioma

Glioma is a relatively low aggressive brain tumor. Although the median survival time of patients for lower-grade glioma (LGG) was longer than that of patients for glioblastoma, the overall survival was still short. Therefore, it is urgent to find out more effective molecular prognostic markers. The role of the Fam20 kinase family in different tumors was an emerging research field. However, the biological function of Fam20C and its prognostic value in brain tumors have rarely been reported. This study aimed to evaluate the value of Fam20C as a potential prognostic marker for LGG. A total of 761 LGG samples (our cohort, TCGA and CGGA) were included to investigate the expression and role of Fam20C in LGG. We found that Fam20C was drastically overexpressed in LGG and was positively associated with its clinical progression. Kaplan-Meier analysis and a Cox regression model were employed to evaluate its prognostic value, and Fam20C was found as an independent risk factor in LGG patients. Gene set enrichment analysis also revealed the potential signaling pathways associated with Fam20C gene expression in LGG; these pathways were mainly enriched in extracellular matrix receptor interactions, cell adhesion, cell apoptosis, NOTCH signaling, cell cycle, etc. In summary, our findings provide insights for understanding the potential role of Fam20C and its application as a new prognostic biomarker for LGG.

Association between dietary glycemic index and glycemic load and glioma: a case-control study

OBJECTIVE

Although glycemic index (GI) and load (GL) have been linked with several health outcomes, no information is available linking dietary GI and GL with glioma. This study aimed to investigate the relationship between dietary GI and GL and odds of glioma.

METHODS

This hospital-based case-control study was conducted between November 2009 and September 2011 in the hospital affiliated to Shahid Beheshti University of Medical Sciences. We recruited 128 newly diagnosed cases of glioma and 256 age- and sex-matched controls. All cases were pathologically diagnosed with glioma patients, with no history of any type of other pathologically confirmed cancers and chemotherapy or radiotherapy (due to cancers). Dietary GI and GL were measured by using a validated, self-administered, dish-based, semi-quantitative food-frequency questionnaire.

RESULT

A significant positive association was found between dietary GI and glioma (OR: 3.01; 95% CI: 1.75-5.17, P < 0.001); such that after considering for potential confounders, participants in the highest tertile of dietary GI had 3.51 times greater risk of glioma than those in the lowest tertile (OR: 3.51; 95% CI: 1.69-7.28, P_trend = 0.001). Furthermore, we observed a significant positive association between dietary and glioma (OR: 3.74; 95% CI: 1.97-6.11, P_trend < 0.001). This association remained significant even after further controlling for potential confounders (OR: 2.42; 95% CI: 1.02-5.69, P_trend= 0.04).

DISCUSSION

We observed a significant positive association between dietary GI and GL and risk of glioma in adults. However, prospective cohort studies are required to confirm this association.

IGFBP7 overexpression promotes acquired resistance to AZD9291 in non-small cell lung cancer

AZD9291 (osimertinib) is the third-generation EGFR-TKI treat for EGFR mutated NSCLC patients. Despite its encouraging efficacy in clinical, acquired resistance is still inevitable. The mechanism of drug resistance needs to be further explored. In a previous study, we established an AZD9291-resistant cell strain named HCC827/AZDR. We found that insulin-like growth factor binding protein 7 (IGFBP7) expression was markedly increased in HCC827/AZDR cells and AZD9291-resistant patients by RNA sequencing and immunohistochemical analysis, respectively. Reduced IGFBP7 in HCC827/AZDR cells by si-RNA interference recovered the sensitivity to AZD9291 partially and increased AZD9291-induced cell apoptosis. Enhancing IGFBP7 expression in EGFR-mutated non-small cell lung cancer (NSCLC) cells using lentiviruses infection reduced their sensitivity to AZD9291. This study is the first to discover that high IGFBP7 expression could occur following treatment with AZD9291. This might be one of the mechanisms underlying AZD9291 resistance and a potential therapeutic target following AZD9291 resistance.

Association of lipoproteins and thyroid hormones with cognitive dysfunction in patients with systemic lupus erythematosus

Background

Neuropsychiatric manifestations occur in up to 75% of adult systemic lupus erythematosus (SLE) patients and are one of the major causes of death in SLE patients. Cognitive dysfunction is a typical clinical feature of neuropsychiatric SLE (NPSLE), which seriously affects the quality of life of patients. Dyslipidaemia and thyroid symptoms, which are prevalent in SLE patients, have both been related to neuropsychiatric disturbances, including significant psychiatric and cognitive disturbances. This study aimed to investigate whether cognitive dysfunction in patients with SLE was related to the expression of serum thyroid hormone and lipoprotein levels.

Methods

A total of 121 patients with SLE and 65 healthy controls (HCs) at Nanjing Drum Tower Hospital completed a cognitive function test, and 81 SLE patients were divided into a high-cognition (n = 33) group and a low-cognition group (n = 48). The clinical and laboratory characteristics of the patients were compared; moreover, correlations between serum HDL-C, LDL-C, F-T3 and F-T4 levels and cognitive function were analysed. Serum levels of APOE, APOA1, IGF-1, and IGFBP7 in 81 patients were detected by ELISA, and the correlation between these four proteins and cognition was analysed separately.

Results

The patients with SLE with abnormal cognitive function were less educated than the HCs. For low-cognition patients, the levels of albumin, F-T3 (P <  0.05) and F-T4 decreased, while D-dimer, anti-dsDNA antibody, and IgM levels increased. Serum F-T3 and F-T4 levels positively correlated with cognition. Furthermore, serum protein levels of APOE and APOA1 showed no difference between the high- and low-cognition groups. However, the serum APOE levels were negatively correlated with line orientation scores, and APOA1 levels were positively correlated with coding scores.

Conclusions

Serum F-T3 and F-T4 levels were both positively correlated with four indexes of cognition (language was the exception), while serum APOE levels were negatively correlated with line orientation scores, APOA1 levels were positively correlated with coding scores, and IGFBP7 levels were negatively correlated with figure copy scores. These results demonstrated that F-T3 and F-T4 might be clinical biomarkers of cognitive dysfunction in SLE.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41927-021-00190-7.

Patterns of Interaction Between Diffuse Low-Grade Glioma and Pregnancy: An Institutional Case Series

BACKGROUND

The occurrence of pregnancy in patients with low-grade glioma (LGG) constitutes a unique therapeutic challenge. Owing to the rarity of cases, there is a dearth of information in existing literature.

METHODS

We retrospectively identified all patients with a diagnosis of LGG and pregnancy at some point during their illness. Clinical course and obstetrical outcomes were reviewed. A volumetric analysis of tumor growth rate in association with pregnancy was performed.

RESULTS

Of 15 women identified, 13 (86.7%) had a prepregnancy LGG diagnosis. Of the 2 patients in whom LGG was diagnosed during pregnancy, one underwent upfront surgery, and the other had watchful waiting with resection after 60 weeks. Nine patients (60.0%) remained asymptomatic during pregnancy, while 5 (33.3%) experienced recurrence of seizures. There was one case of transformation of an astrocytoma to glioblastoma during the third trimester, which was resected emergently. In 10 cases, progression occurred after pregnancy at a median interval of 24.2 months (interquartile range 6.6-37.5 months), with progression within 6 months of delivery in 2 cases. Mean (SD) growth rate during pregnancy was 7.8 (22.2) mm/year compared with 0.62 (1.12) mm/year before pregnancy and 0.29 (1.18) mm/year after pregnancy; the difference did not reach statistical significance (P = 0.306).

CONCLUSIONS

Pregnancy was associated with clinical deterioration in one third of patients. No significant change in growth rate was identified. Time to progression and malignant dedifferentiation were unaffected. Patients with LGG wishing to pursue pregnancy should be counseled regarding the risk of complications, and if pregnancy is pursued, close neurological and obstetrical follow-up is recommended.

Roles of PINK1 in regulation of systemic growth inhibition induced by mutations of PTEN in Drosophila

The maintenance of mitochondrial homeostasis requires PTEN-induced kinase 1 (PINK1)-dependent mitophagy, and mutations in PINK1 are associated with Parkinson's disease (PD). PINK1 is also downregulated in tumor cells with PTEN mutations. However, there is limited information concerning the role of PINK1 in tissue growth and tumorigenesis. Here, we show that the loss of pink1 caused multiple growth defects independent of its pathological target, Parkin. Moreover, knocking down pink1 in muscle cells induced hyperglycemia and limited systemic organismal growth by the induction of Imaginal morphogenesis protein-Late 2 (ImpL2). Similarly, disrupting PTEN activity in multiple tissues impaired systemic growth by reducing pink1 expression, resembling wasting-like syndrome in cancer patients. Furthermore, the re-expression of PINK1 fully rescued defects in carbohydrate metabolism and systemic growth induced by the tissue-specific pten mutations. Our data suggest a function for PINK1 in regulating systemic growth in Drosophila and shed light on its role in wasting in the context of PTEN mutations.

IGF-Binding Proteins, Adiponectin, and Survival in Metastatic Colorectal Cancer: Results From CALGB (Alliance)/SWOG 80405

Background

Energy balance-related biomarkers are associated with risk and prognosis of various malignancies. Their relationship to survival in metastatic colorectal cancer (mCRC) requires further study.

Methods

Baseline plasma insulin-like growth factor (IGF)-1, IGF-binding protein (IGFBP)-3, IGFBP-7, C-peptide, and adiponectin were measured at time of trial registration in a prospective cohort of patients with mCRC participating in a National Cancer Institute–sponsored trial of first-line systemic therapy. We used Cox proportional hazards regression to adjust for confounders and examine associations of each biomarker with overall survival (OS) and progression-free survival (PFS). P values are 2-sided.

Results

Median follow-up for 1086 patients was 6.2 years. Compared with patients in the lowest IGFBP-3 quintile, patients in the highest IGFBP-3 quintile experienced an adjusted hazard ratio (HR) for OS of 0.57 (95% confidence interval [CI] = 0.42 to 0.78; P_nonlinearity < .001) and for PFS of 0.61 (95% CI = 0.45 to 0.82; P_trend = .003). Compared with patients in the lowest IGFBP-7 quintile, patients in the highest IGFBP-7 quintile experienced an adjusted hazard ratio for OS of 1.60 (95% CI = 1.30 to 1.97; P_trend < .001) and for PFS of 1.38 (95% CI = 1.13 to 1.69; P_trend < .001). Plasma C-peptide and IGF-1 were not associated with patient outcomes. Adiponectin was not associated with OS; there was a nonlinear U-shaped association between adiponectin and PFS (P_nonlinearity = .03).

Conclusions

Among patients with mCRC, high plasma IGFBP-3 and low IGFBP-7 were associated with longer OS and PFS. Extreme levels of adiponectin were associated with shorter PFS. These findings suggest potential avenues for prognostic and therapeutic innovation.

Insulin Growth Factor Binding Protein 7 (IGFBP7)-Related Cancer and IGFBP3 and IGFBP7 Crosstalk

The insulin/insulin-like growth factors (IGFs) have crucial tasks in the growth, differentiation, and proliferation of healthy and pernicious cells. They are involved in coordinated complexes, including receptors, ligands, binding proteins, and proteases. However, the systems can become dysregulated in tumorigenesis. Insulin-like growth factor-binding protein 7 (IGFBP7) is a protein belonging to the IGFBP superfamily (also termed GFBP-related proteins). Numerous studies have provided evidence that IGFBP3 and IGFBP7 are involved in a variety of cancers, including hepatocellular carcinoma (HCC), breast cancer, gastroesophageal cancer, colon cancer, prostate cancer, among many others. Still, very few suggest an interaction between these two molecules. In studying several cancer types in our laboratories, we found that both proteins share some crucial signaling pathways. The objective of this review is to present a comprehensive overview of the relationship between IGFBP7 and cancer, as well as highlighting IGFBP3 crosstalk with IGFBP7 reported in recent studies.

An Optimised Protocol Harnessing Laser Capture Microdissection for Transcriptomic Analysis on Matched Primary and Metastatic Colorectal Tumours

Generation of large amounts of genomic data is now feasible and cost-effective with improvements in next generation sequencing (NGS) technology. Ribonucleic acid sequencing (RNA-Seq) is becoming the preferred method for comprehensively characterising global transcriptome activity. Unique to cytoreductive surgery (CRS), multiple spatially discrete tumour specimens could be systematically harvested for genomic analysis. To facilitate such downstream analyses, laser capture microdissection (LCM) could be utilized to obtain pure cell populations. The aim of this protocol study was to develop a methodology to obtain high-quality expression data from matched primary tumours and metastases by utilizing LCM to isolate pure cellular populations. We demonstrate an optimized LCM protocol which reproducibly delivered intact RNA used for RNA sequencing and quantitative polymerase chain reaction (qPCR). After pathologic annotation of normal epithelial, tumour and stromal components, LCM coupled with cDNA library generation provided for successful RNA sequencing. To illustrate our framework's potential to identify targets that would otherwise be missed with conventional bulk tumour sequencing, we performed qPCR and immunohistochemical technical validation to show that the genes identified were truly expressed only in certain sub-components. This study suggests that the combination of matched tissue specimens with tissue microdissection and NGS provides a viable platform to unmask hidden biomarkers and provides insight into tumour biology at a higher resolution.

Dietary insulin index and insulin load in relation to glioma: findings from a case-control study

BACKGROUND

Although hyperinsulinemia is assumed to be involved in brain carcinogenesis, data on the link between dietary insulin index (DII) and dietary insulin load (DIL) and risk of glioma are lacking.

OBJECTIVE

The current study aimed to investigate the relation between DII and DIL and risk of glioma in a case-control study among Iranian adults.

METHODS

In this hospital-based case-control study, 128 pathologically confirmed cases of glioma and 256 age and sex-matched controls were enrolled. Dietary intakes of study participants were assessed using a validated Block-format 123-item semi-quantitative FFQ. DII and DIL were computed using a published food insulin index (FII) data.

RESULTS

A significant positive association was found between DIL and glioma (OR: 3.56; 95% CI: 1.85-6.58, P < 0.001); such that after controlling for potential confounders, participants in the highest quartile of DIL had 2.95 times greater odds of glioma than those in the lowest quartile (OR: 2.95; 95% CI: 1.40-6.24, P_trend=0.006). Furthermore, we observed a significant positive association between DII and glioma (OR: 2.65; 95% CI: 1.43-4.93, P_trend= 0.001). This association remained significant even after considering energy intake (OR: 2.66; 95% CI: 1.43-4.95, P_trend = 0.001). However, when further potential confounders were taken into account, this relationship became non-significant (OR: 1.87; 95% CI: 0.92-3.80, P_trend = 0.03), despite a significant trend of increased odds ratios (P = 0.03).

CONCLUSIONS

In conclusion, we found a significant positive association between DIL and odds of glioma. DII was not significantly associated with odds of glioma after controlling for confounders.

IGFBP7 contributes to epithelial-mesenchymal transition of HPAEpiC cells in response to radiation

Radiation-induced lung injury (RILI) frequently occurs in patients with thoracic malignancies. In response to radiation, alveolar epithelial cells (AEC) undergo epithelial-mesenchymal transition (EMT) and contribute to the pathogenesis of RILI. Insulin-like growth factor binding protein 7 (IGFBP7) is reported as a downstream mediator of transforming growth factor-β1 (TGF-β1) pathway, which plays a crucial role in radiation-induced EMT. In the present study, the levels of IGFBP7 and TGF-β1 were simultaneously increased in experimental RILI models and radiation-treated AEC (human pulmonary alveolar epithelial cells [HPAEpic]). The expression of IGFBP7 in radiation-treated HPAEpic cells was obviously inhibited by the specific inhibitor of TGF-β receptor antagonist SB431542 and TGF-β1 neutralizing antibody, and time-dependently enhanced by TGF-β1 treatment. Moreover, IGFBP7 knockdown significantly attenuated the effects of radiation on morphology change, cell migration, expression of EMT-related markers (E-cadherin, α-SMA, and Vimentin), and phosphorylation of extracellular-signal-regulated kinase (ERK). The effects of IGFBP7 overexpression on the expression of EMT-related markers were partially reversed by the ERK inhibitor PD98059. In conclusion, IGFBP7, was enhanced by TGF-β1, may be involved in radiation-induced EMT of AEC via the ERK signaling pathway, thus contributing to the pathogenesis of RILI.

Epigenetic Downregulation and Growth Inhibition of IGFBP7 in Gastric Cancer

Background:

Insulin-like growth factor-binding protein 7 (IGFBP7) has been found to be a tumor suppressor in several human cancers, but the role of IGFBP7 in gastric cancer has not yet been fully investigated. Herein, we examined the epigenetic downregulation of IGFBP7 expression in gastric cancer.

Methods:

Expression and methylation of IGFBP7 in gastric cancer cells and primary gastric cancer patients were determined using qRT-PCR, western blot, immunohistochemistry, and methylation specific-PCR, respectively. The effects of IGFBP7 on gastric cancer cells were investigated by various experimental conditions, such as proliferation, colony formation, apoptosis, invasion, and migration assay.

Results:

IGFBP7 methylation was inversely correlated with IGFBP7 expression in gastric cancer. Univariate and multivariate analysis showed that IGFBP7 expression and tumor stage were independent prognostic factors. IGFBP7 knockdown increased gastric cancer cell growth, invasion, and migration, whereas IGFBP7 overexpression in gastric cancer cells induced cell growth inhibition and apoptosis.

Conclusion:

Our data suggest that IGFBP7 functions as a tumor suppressor in gastric cancer via an epigenetic pathway.

IGFBP-7 inhibits the differentiation of oligodendrocyte precursor cells via regulation of Wnt/β-Catenin signaling

Oligodendrocytes (OLs) are glial cells that form myelin sheaths in the central nervous system. Myelin sheath plays important role in nervous system and loss of it in neurodegenerative diseases can lead to impairment of movement. Understanding the signals and factors that regulate OL differentiation can help to address novel strategies for improving myelin repair in neurodegenerative diseases. The aim of this study was to investigate the role of insulin-like growth factor-binding proteins 7 (IGFBP-7) in differentiating OL precursor cells (OPCs). It was found that oligodendrocyte precursors undergoing differentiation were accompanied by selective expression of IGFBP-7. In addition, knockdown of IGFBP-7 promoted differentiation of oligodendrocytes and increased formation of myelin in cultured cells. In contrast, excessive expression of IGFBP-7 inhibited differentiation of oligodendrocytes. Furthermore, overexpression of IGFBP-7 in oligodendrocyte precursor cells increased transcription of Wnt target genes and promoted β-Catenin nuclear translocation. These findings suggest that IGFBP-7 negatively regulates differentiation of oligodendrocyte precursor cells via regulation of Wnt/β-Catenin signaling.

Testicular cancer from diagnosis to epigenetic factors

Testicular cancer (TC) is one of the most common neoplasms that occurs in male and includes germ cell tumors (GCT), sex cord-gonadal stromal tumors and secondary testicular tumors. Diagnosis of TC involves the evaluation of serum tumor markers alpha-fetoprotein, human chorionic gonadotropin and lactate dehydrogenase, but clinically several types of immunohistochemical markers are more useful and more sensitive in GCT, but not in teratoma. These new biomarkers are genes expressed in primordial germ cells/gonocytes and embryonic pluripotency-related cells but not in normal adult germ cells and they include PLAP, OCT3/4 (POU5F1), NANOG, SOX2, REX1, AP-2γ (TFAP2C) and LIN28. Gene expression in GCT is regulated, at least in part, by DNA and histone modifications, and the epigenetic profile of these tumours is characterised by genome-wide demethylation. There are different epigenetic modifications in TG-subtypes that reflect the normal developmental switch in primordial germ cells from an under- to normally methylated genome. The main purpose of this review is to illustrate the findings of recent investigations in the classification of male genital organs, the discoveries in the use of prognostic and diagnostic markers and the epigenetic aberrations mainly affecting the patterns of DNA methylation/histone modifications of genes (especially tumor suppressors) and microRNAs (miRNAs).

Interactions between glioma and pregnancy: insight from a 52-case multicenter series

OBJECTIVE The goal of this study was to provide insight into the influence of gliomas on gestational outcomes, the impact of pregnancy on gliomas, and the identification of patients at risk. METHODS In this multiinstitutional retrospective study, the authors identified 52 pregnancies in 50 women diagnosed with a glioma. RESULTS For gliomas known prior to pregnancy (n = 24), we found the following: 1) An increase in the quantified imaging growth rates occurred during pregnancy in 87% of cases. 2) Clinical deterioration occurred in 38% of cases, with seizures alone resolving after delivery in 57.2% of cases. 3) Oncological treatments were immediately performed after delivery in 25% of cases. For gliomas diagnosed during pregnancy (n = 28), we demonstrated the following: 1) The tumor was discovered during the second and third trimesters in 29% and 54% of cases, respectively, with seizures being the presenting symptom in 68% of cases. 2) The quantified imaging growth rates did not significantly decrease after delivery and before oncological treatment. 3) Clinical deterioration resolved after delivery in 21.4% of cases. 4) Oncological treatments were immediately performed after delivery in 70% of cases. Gliomas with a high grade of malignancy, negative immunoexpression of alpha-internexin, or positive immunoexpression for p53 were more likely to be associated with tumor progression during pregnancy. Deliveries were all uneventful (cesarean section in 54.5% of cases and vaginal delivery in 45.5%), and the infants were developmentally normal. CONCLUSIONS When a woman harboring a glioma envisions a pregnancy, or when a glioma is discovered in a pregnant patient, the authors suggest informing her and her partner that pregnancy may impact the evolution of the glioma clinically and radiologically. They strongly advise a multidisciplinary approach to management. ■ CLASSIFICATION OF EVIDENCE Type of question: association; study design: case series; evidence: Class IV.

Metastatic biomarkers in synovial sarcoma

Synovial sarcoma (SS) is an aggressive soft tissue sarcoma (STS) that typically occurs in the extremities near a joint. Metastatic disease is common and usually occurs in the lungs and lymph nodes. Surgical management is the mainstay of treatment with chemotherapy and radiation typically used as adjuvant treatment. Although chemotherapy has a positive impact on survival, the prognosis is poor if metastatic disease occurs. The biology of sarcoma invasion and metastasis remain poorly understood. Chromosomal translocation with fusion of the SYT and SSX genes has been described and is currently used as a diagnostic marker, although the full impact of the fusion is unknown. Multiple biomarkers have been found to be associated with SS and are currently under investigation regarding their pathways and mechanisms of action. Further research is needed in order to develop better diagnostic screening tools and understanding of tumor behavior. Development of targeted therapies that reduce metastatic events in SS, would dramatically improve patient prognosis.

Modulated DISP3/PTCHD2 expression influences neural stem cell fate decisions

Neural stem cells (NSCs) are defined by their dual ability to self-renew through mitotic cell division or differentiate into the varied neural cell types of the CNS. DISP3/PTCHD2 is a sterol-sensing domain-containing protein, highly expressed in neural tissues, whose expression is regulated by thyroid hormone. In the present study, we used a mouse NSC line to investigate what effect DISP3 may have on the self-renewal and/or differentiation potential of the cells. We demonstrated that NSC differentiation triggered significant reduction in DISP3 expression in the resulting astrocytes, neurons and oligodendrocytes. Moreover, when DISP3 expression was disrupted, the NSC "stemness" was suppressed, leading to a larger population of cells undergoing spontaneous neuronal differentiation. Conversely, overexpression of DISP3 resulted in increased NSC proliferation. When NSCs were cultured under differentiation conditions, we observed that the lack of DISP3 augmented the number of NSCs differentiating into each of the neural cell lineages and that neuronal morphology was altered. In contrast, DISP3 overexpression resulted in impaired cell differentiation. Taken together, our findings imply that DISP3 may help dictate the NSC cell fate to either undergo self-renewal or switch to the terminal differentiation cell program.

Does a blue crab putative insulin-like peptide binding protein (ILPBP) play a role in a virus infection?

Insulin-like peptides (ILPs) have regulatory roles in reproduction, development and metabolism in invertebrates. The mode of ILP actions has not been well studied in invertebrates in regard to the role of binding partners, i.e., ILP binding protein (ILPBP). In this study, the full-length cDNA of Callinectes sapidus ILPBP (Cas-ILPBP, 960 bp) has been isolated using RACE cloning, having short 5' and 3' UTRs of 30 and 162 bp, respectively. The predicted precursor of Cas-ILPBP (255 aa) contains, in order a signal peptide (23 aa), an insulin-like growth factor (IGF) binding (IB) domain (79 aa), a kazal-type serine protease inhibitor (KI) domain (36 aa) and an immunoglobulin (Ig) domain (101 aa). Phylogenetic analysis shows that Cas-ILPBP is grouped with the ILPBPs of other crustacean species, and it shares the closest relationship with the ILPBP from another crab species, Scylla paramamosain. Transcripts of Cas-ILPBP are found in all examined tissues, with the highest levels in the nervous tissues (eyestalk ganglia, brain and thoracic ganglia complex) and followed by midgut, the pericardial organ, abdominal muscle and the heart. As Cas-ILPBP contains a putative Ig domain, it is hypothesized that this protein may be involved in immunity, particularly in the adult females infected with a reo-like virus (CsRV1). The expression levels of Cas-ILPBP are examined in several tissues (hemocytes, midgut, eyestalk ganglia) from the animals carrying varying levels of CsRV1 at 17 and 23 °C water temperatures. Cas-ILPBP levels in the midgut are most significantly affected by high levels of CsRV1 infection. Reduction in Cas-ILPBP levels in the midguts is noted from the animals infected with high levels of CsRV1 that show reduced or stop feeding activity, indicating that it may play an important role in midgut functions such as digestion and nutrient absorption.

A Single Kinase Generates the Majority of the Secreted Phosphoproteome

The existence of extracellular phosphoproteins has been acknowledged for over a century. However, research in this area has been undeveloped largely because the kinases that phosphorylate secreted proteins have escaped identification. Fam20C is a kinase that phosphorylates S-x-E/pS motifs on proteins in milk and in the extracellular matrix of bones and teeth. Here, we show that Fam20C generates the majority of the extracellular phosphoproteome. Using CRISPR/Cas9 genome editing, mass spectrometry, and biochemistry, we identify more than 100 secreted phosphoproteins as genuine Fam20C substrates. Further, we show that Fam20C exhibits broader substrate specificity than previously appreciated. Functional annotations of Fam20C substrates suggest roles for the kinase beyond biomineralization, including lipid homeostasis, wound healing, and cell migration and adhesion. Our results establish Fam20C as the major secretory pathway protein kinase and serve as a foundation for new areas of investigation into the role of secreted protein phosphorylation in human biology and disease.

IGFBP7 promotes hemocyte proliferation in small abalone Haliotis diversicolor, proved by dsRNA and cap mRNA exposure

Insulin-like growth factor binding protein 7 (IGFBP7) binds IGFs with a low affinity, but in contrast, recognizes insulin with a high affinity. Many studies show that IGFBP7 involves several cellular processes of vertebrates and functions as a tumor suppressor gene in different tumors. However, the function of IGFBP7 in invertebrates is unclear. In this research, we studied the function of IGFBP7 in the proliferation of small abalone Haliotis diversicolor hemocytes by exposure to dsRNA or cap mRNA of saIGFBP7. We found that exposure to dsRNA or cap mRNA of saIGFBP7 could significantly affect the mRNA and protein expression of IGFBP7 in cultured small abalone hemocytes (p<0.05). There was a significant increase in hemocyte density and the number of adherent hemocytes after exposure to cap mRNA of saIGFBP7 (p<0.05). Similarly, exposure to dsRNA of saIGFBP7 could significantly decrease the hemocyte density and the number of adherent hemocytes (p<0.05). These findings suggest that IGFBP7 increases hemocyte growth. It is the first time to report the effect of IGFBP7 on the proliferation of marine invertebrate cells.

Serum IGFBP7 levels associate with insulin resistance and the risk of metabolic syndrome in a Chinese population

Metabolic syndrome (MetS), one of the major public health concerns, is regarded as the “common soil” of incidence of common chronic diseases and may increase the risk of type 2 diabetes. The predominant underlying mechanism of MetS is insulin resistance (IR). Additionally, previous studies have indicated that IGFBP7 has high affinity of binding with insulin and might induce IR. The objective of this study was to firstly evaluate the associations of serum IGFBP7 levels with IR and MetS with a relatively large sample and population based design. In a population based MetS case-control study, HOMA-IR was used to evaluate the insulin sensitivity and serum IGFBP7 levels were determined with chemiluminescence–linked immunoassay. As a result, the subjects of MetS and IR had higher serum levels of IGFBP7 than control healthy subjects. High serum IGFBP7 levels increased the risk of MetS and IR. Serum IGFBP7 levels were also found to be significantly correlated with metabolic-associated parameters of Waist-to-hip ratio (WHR), HDL and LDL. These findings suggest that serum IGFBP7 levels are associated with IR and MetS, providing new insight into the mechanism of IR and Mets. IGFBP7 may be a potential interventional target for IR and Mets.

Insulin-like growth factor-binding protein 7 is up-regulated during EAE and inhibits the differentiation of oligodendrocyte precursor cells

Oligodendrocyte precursor cells (OPCs) differentiation failure is one of the leading causes for remyelination defects in the demyelinating lesions of multiple sclerosis (MS). In this study, we explored the roles of insulin-like growth factor-binding proteins 7 (IGFBP-7) on OPCs differentiation during experimental autoimmune encephalomyelitis (EAE). We first investigated the expression pattern of IGFBP-7 by real-time PCR and immunofluorescence staining. It showed that IGFBP-7 was expressed in astrocytes (ACs), oligodendrocytes (OLs) and neurons both in vitro and in vivo. The mRNA and protein level of IGFBP-7 was also increased in the spinal cord from mice at the peak of EAE disease. Next we found that IGFBP-7 acted as a negatively regulator of the OPCs differentiation. Together, these data suggest that IGFBP-7 was up regulated during EAE and inhibit the transition from OPCs to mature OLs, implying its use as a potential therapeutic target for the treatment of inflammatory demyelinating diseases.

Insulin-like growth factor system in cancer: novel targeted therapies

Insulin-like growth factors (IGFs) are essential for growth and survival that suppress apoptosis and promote cell cycle progression, angiogenesis, and metastatic activities in various cancers. The IGFs actions are mediated through the IGF-1 receptor that is involved in cell transformation induced by tumour. These effects depend on the bioavailability of IGFs, which is regulated by IGF binding proteins (IGFBPs). We describe here the role of the IGF system in cancer, proposing new strategies targeting this system. We have attempted to expand the general viewpoint on IGF-1R, its inhibitors, potential limitations of IGF-1R, antibodies and tyrosine kinase inhibitors, and IGFBP actions. This review discusses the emerging view that blocking IGF via IGFBP is a better option than blocking IGF receptors. This can lead to the development of novel cancer therapies.

Low levels of IGFBP7 expression in high-grade serous ovarian carcinoma is associated with patient outcome

BACKGROUND

Insulin-like growth factor binding protein 7 (IGFBP7) has been suggested to act as a tumour suppressor gene in various human cancers, yet its role in epithelial ovarian cancer (EOC) has not yet been investigated. We previously observed that IGFBP7 was one of several genes found significantly upregulated in an EOC cell line model rendered non-tumourigenic as consequence of genetic manipulation. The aim of the present study was to investigate the role of IGFBP7 in high-grade serous ovarian carcinomas (HGSC), the most common type of EOC.

METHODS

We analysed IGFBP7 gene expression in 11 normal ovarian surface epithelial cells (NOSE), 79 high-grade serous ovarian carcinomas (HGSC), and seven EOC cell lines using a custom gene expression array platform. IGFBP7 mRNA expression profiles were also extracted from publicly available databases. Protein expression was assessed by immunohistochemistry of 175 HGSC and 10 normal fallopian tube samples using tissue microarray and related to disease outcome. We used EOC cells to investigate possible mechanisms of gene inactivation and describe various in vitro growth effects of exposing EOC cell lines to human recombinant IGFBP7 protein and conditioned media.

RESULTS

All HGSCs exhibited IGFBP7 expression levels that were significantly (p = 0.001) lower than the mean of the expression value of NOSE samples and that of a whole ovary sample. IGFBP7 gene and protein expression were lower in tumourigenic EOC cell lines relative to a non-tumourigenic EOC cell line. None of the EOC cell lines harboured a somatic mutation in IGFBP7, although loss of heterozygosity (LOH) of the IGFBP7 locus and epigenetic methylation silencing of the IGFBP7 promoter was observed in two of the cell lines exhibiting loss of gene/protein expression. In vitro functional assays revealed an alteration of the EOC cell migration capacity. Protein expression analysis of HGSC samples revealed that the large majority of tumour cores (72.6%) showed low or absence of IGFBP7 staining and revealed a significant correlation between IGFBP7 protein expression and a prolonged overall survival (p = 0.044).

CONCLUSION

The low levels of IGFPB7 in HGSC relative to normal tissues, and association with survival are consistent with a purported role in tumour suppressor pathways.

Insulin like growth factor binding protein 7 (IGFBP7) expression is linked to poor prognosis but may protect from bone disease in multiple myeloma

Background

Insulin like growth factor binding protein 7 (IGFBP7) is a secreted protein binding insulin like growth factor 1 (IGF-1), insulin, vascular endothelial growth factor A (VEGFA), and activin A. It antagonizes bone morphogenetic proteins and is involved in the tumour propagation of solid as well as haematological malignancies. Its role in multiple myeloma (MM) is not defined so far. We therefore aim here to investigate its prognostic and pathophysiological role in MM.

Methods

The clinical significance of IGFBP7 gene expression was investigated by gene expression profiling in two independent cohorts (n = 948) of newly-diagnosed MM patients. Methylation of the IGFBP7 promoter was analysed by pyrosequencing and treatment of MM cell lines with 5-aza-2-deoxycytidine. The impact of IGFBP7 on MM cells was studied by CCK-8 assay, BrdU assay and flow cytometry, respectively. IGFBP7 expression in bone marrow stromal cells (BMSCs) was studied by quantitative RT-PCR. For osteoblast development, immortalized and primary human BMSCs were cultured in osteogenic differentiation medium for 7–14 days in the presence of recombinant human IGFBP7 and/or activin A.

Results

Median IGFBP7 expression is significantly lower in CD138-purified plasma cells from individuals with MGUS and MM, compared to normal bone marrow plasma cells. IGFBP7 gene expression in MM cells is regulated by methylation, shown by pyrosequencing and exposure to demethylating agents (5-aza-2-deoxycytidine). High expression of IGFBP7 in MM cells is associated with adverse survival in two independent cohorts of 247 and 701 newly-diagnosed MM patients treated with high-dose therapy and autologous stem cell transplantation. IGFBP7 is associated with prognostically adverse chromosomal aberrations (t(4;14) and gain of 1q21), MMSET expression, and higher myeloma cell proliferation. In vitro, IGFBP7 overcomes activin A induced osteoblast suppression and promotes osteogenesis. MM cells downregulate IGFBP7 in stromal cells, possibly contributing to the osteoblast suppression found in MM. Conversely, higher IGFBP7 expression is associated with a lower probability of myeloma bone disease.

Conclusions

Our data indicate that IGFBP7 expression is a marker for a specific methylation pattern in myeloma, linked to translocation t(4;14) associated MMSET expression, showing clinical features of adverse prognosis with absence of myeloma bone disease.

Electronic supplementary material

The online version of this article (doi:10.1186/s13045-014-0105-1) contains supplementary material, which is available to authorized users.

Insulin-like growth factor binding protein-related protein 1 (IGFBPrP1) contributes to liver inflammation and fibrosis via activation of the ERK1/2 pathway

BACKGROUND AND AIM

Previously, we suggested that IGFBPrP1 played a major role in hepatic stellate cell (HSC) activation, yet the molecular mechanism of IGFBPrP1 in hepatic fibrosis is unclear. The ERK pathway is involved in activation of HSCs. This study investigated the involvement of the ERK1/2 pathway in IGFBPrP1-induced liver inflammation and fibrosis.

METHODS

An adenoviral vector encoding IGFBPrP1 (AdIGFBPrP1) was constructed. Rats received AdIGFBPrP1 or CAd (vector control) via their tail vein injection. One hour prior to adenoviral injections, rats were intraperitoneally administrated with 10 mg/kg U0126 (a specific MEK/ERK1/2 inhibitor) or DMSO (vehicle control). At weeks 2 or 4 post-gene transduction, serum samples were obtained and the levels of liver enzymes and hydroxyproline were determined. Liver tissue were histologically evaluated for inflammation and fibrosis. The expression of α-SMA and ECM were evaluated by qRT-PCR and western blotting.

RESULTS

After transduction, IGFBPrP1 expression significantly increased in livers and transduced cells. MEK/ERK1/2 inhibition administration of AdIGFBPrP1-treated rats and cells significantly blocked AdIGFBPrP1-induced activation of ERK1/2. U0126 significantly down-regulated the number of F4/80-positive cells and CD3-positive cells (markers of liver inflammation), the expression of α-SMA and the concentration of ECM components in vivo. In addition, α-SMA and TGF-β1 levels in AdIGFBPrP1 HSCs were markedly inhibited by a MEK/ERK1/2 inhibitor, indicating that HSC activation was inhibited.

CONCLUSION

These findings suggest that IGFBPrP1 acts as an initiator of liver fibrosis by inducing inflammation, HSC activation and ECM deposition through the ERK1/2 pathway.

IGFBPrP1 induces liver fibrosis by inducing hepatic stellate cell activation and hepatocyte apoptosis via Smad2/3 signaling

AIM: To investigate the role and mechanism of insulin-like growth factor binding protein-related protein 1 (IGFBPrP1) in the development of liver fibrosis.

METHODS: An in vitro model using hepatic stellate cell (HSC)-T6 cells and an in vivo model of rat liver overexpressing IGFBPrP1 were established using an IGFBPrP1-expressing recombinant adenovirus. The expression of IGFBPrP1 was examined by immunofluorescence, and the expression of collagen I and fibronectin was measured by real-time reverse transcription-polymerase chain reaction and Western blot analysis. The expression of Smad2/3 and p-Smad2/3 was examined by Western blot and immunohistochemistry. A shSmad3-expressing recombinant adenovirus (AdshSmad3) was designed and used to knockdown the Smad3 gene in HSC-T6 cells and rat liver fibrosis transfected with IGFBPrP1. The expression of collagen I, fibronectin, and α-smooth muscle actin (α-SMA) was determined by Western blot analysis and immunohistochemistry. Hepatocyte apoptosis was assessed using TUNEL assay.

RESULTS: IGFBPrP1 overexpression induced collagen deposition and up-regulated the expression of α-SMA and p-Smad2/3, and AdshSmad3 inhibited IGFBPrP1-stimulated p-Smad2/3 activation and the expression of α-SMA, collagen I and fibronectin in HSC-T6 cells. Similarly, increased hepatocyte apoptosis (38.56% ± 3.42% vs 0.24% ± 0.03%, P < 0.05), α-SMA positive stained cells (29.84% ± 1.36% vs 5.83% ± 1.47%, P < 0.05), and increased numbers of Smad3 (35.88% ± 2.15% vs 10.24% ± 1.31%, P < 0.05) and p-Smad2/3 positive cells (28.87% ± 2.73% vs 8.23% ± 0.98%, P < 0.05) were detected in the livers of IGFBPrP1-overexpressing rats compared with the control group. Moreover, AdshSmad3 reduced IGFBPrP1-stimulated Smad3 expression and attenuated α-SMA expression (29.84% ± 1.36% vs 8.23% ± 1.28%, P < 0.05), hepatocyte apoptosis (38.56% ± 3.42% vs 6.75% ± 0.52%, P < 0.05), and both collagen I and fibronectin deposition in the livers of AdIGFBPrP1-treated rats.

CONCLUSION: IGFBPrP1 induces liver fibrosis by mediating the activation of hepatic stellate cells and hepatocyte apoptosis in a Smad3-dependent mechanism.

IGFBP7, a novel tumor stroma marker, with growth-promoting effects in colon cancer through a paracrine tumor-stroma interaction

The activated tumor stroma participates in many processes that control tumorigenesis, including tumor cell growth, invasion and metastasis. Cancer-associated fibroblasts (CAFs) represent the major cellular component of the stroma and are the main source for connective tissue components of the extracellular matrix and various classes of proteolytic enzymes. The signaling pathways involved in the interactions between tumor and stromal cells and the molecular characteristics that distinguish normal 'resting' fibroblasts from cancer-associated or '-activated' fibroblasts remain poorly defined. Recent studies emphasized the prognostic and therapeutic significance of CAF-related molecular signatures and a number of those genes have been shown to serve as putative therapeutic targets. We have used immuno-laser capture microdissection and whole-genome Affymetrix GeneChip analysis to obtain transcriptional signatures from the activated tumor stroma of colon carcinomas that were compared with normal resting colonic fibroblasts. Several members of the Wnt-signaling pathway and gene sets related to hypoxia, epithelial-to-mesenchymal transition (EMT) and transforming growth factor-β (TGFβ) pathway activation were induced in CAFs. The putative TGFβ-target IGFBP7 was identified as a tumor stroma marker of epithelial cancers and as a tumor antigen in mesenchyme-derived sarcomas. We show here that in contrast to its tumor-suppressor function in epithelial cells, IGFPB7 can promote anchorage-independent growth in malignant mesenchymal cells and in epithelial cells with an EMT phenotype when IGFBP7 is expressed by the tumor cells themselves and can induce colony formation in colon cancer cells co-cultured with IGFBP7-expressing CAFs by a paracrine tumor-stroma interaction.

Insulin-like growth factor binding protein-related protein 1 and cancer

Insulin-like growth factor binding protein-related protein 1 (IGFBP-rP1) belongs to the IGFBP family whose members have a conserved structural homology. It has a low affinity for IGFs and a high affinity for insulin, suggesting that IGFBP-rP1 may have a biological function distinct from other members of the family. IGFBP-rP1 is ubiquitously expressed in normal human tissues and has diverse biological functions, regulating cell proliferation, apoptosis and senescence; it may also have a key role in vascular biology. Increasing evidence suggests that IGFBP-rP1 acts as a tumor suppressor. It elicits its biological effects by both insulin/IGF-dependent and -independent mechanisms. This paper provides a brief overview of the structure and regulation of IGFBP-rP1 and its various biological functions in cancer, as well as the underlying molecular mechanisms.

Insulin like growth factor binding protein 4 promotes GBM progression and regulates key factors involved in EMT and invasion

Insulin like growth factor binding protein 4 (IGFBP4) regulates growth and development of tissues and organs by negatively regulating IGF signaling. Among most cancers, IGFBP4 has growth inhibitory role and reported as a down-regulated gene, except for renal cell carcinoma, wherein IGFBP4 promotes tumor progression. IGFBP4 expression has been shown to be higher in increasing grades of astrocytoma. However, the functional role of IGFBP4 in gliomas has not been explored. Surgical biopsies of 20 normal brain and 198 astrocytoma samples were analyzed for IGFBP4 expression by qRT-PCR. Highest expression of IGFBP4 mRNA was seen in GBM tumors compared to control brain tissues (median log2 of 2.035, p < 0.0001). Immunohistochemical analysis of 53 tissue samples revealed predominant nuclear staining of IGFBP4, seen maximally in GBMs when compared to DA and AA tumors (median LI = 29.12 ± 16.943, p < 0.001). Over expression of IGFBP4 in U343 glioma cells resulted in up-regulation of molecules involved in tumor growth, EMT and invasion such as pAkt, pErk, Vimentin, and N-cadherin and down-regulation of E-cadherin. Functionally, IGFBP4 over expression in these cells resulted in increased proliferation, migration and invasion as assessed by MTT, transwell migration, and Matrigel invasion assays. These findings were confirmed upon IGFBP4 knockdown in U251 glioma cells. Our data suggest a pro-tumorigenic role for IGFBP4 in glioma.

IGFBP7 is associated with poor prognosis in oesophageal adenocarcinoma and is regulated by promoter DNA methylation

BACKGROUND

We examined whether silencing of IGFBP7 was associated with survival in patients with oesophageal adenocarcinoma.

METHODS

Protein expression of IGFBP7 was determined using immunohistochemistry in a tissue microarray representing tumours from 65 patients with oesophageal adenocarcinoma who had not had neoadjuvant therapy. DNA methylation of the IGFBP7 promoter was determined with the melt curve analysis in cell lines and patient tissues.

RESULTS

Expression of IGFBP7 was observed in the oesophageal adenocarcinoma of 34 out of 65 (52%) patients and was associated with significantly reduced median (11 vs 92 months) and 5-year survival (25% vs 52%). Multivariate analysis identified expression as an independent prognostic indicator for survival (hazard ratio=3.24, 95% confidence interval=1.58-6.67, P-value=0.0014). Hypermethylation of IGFBP7 was associated with silencing of gene expression in cell lines and patient tissues (P-value=0.0225). Methylation was observed in the squamous mucosa of 2 out of 15 (13%) patients with Barrett's oesophagus and 3 out of 17 (18%) with oesophageal adenocarcinoma. Methylation was observed in 14 out of 18 (78%) of biopsies of Barrett's mucosa and 23 out of 34 (68%) patients with oesophageal adenocarcinoma.

CONCLUSION

Reduced IGFBP7 protein expression was associated with longer survival in patients with oesophageal adenocarcinoma. Methylation of the IGFBP7 promoter was associated with silencing of gene expression and was frequent in Barrett's oesophagus and oesophageal adenocarcinoma.

Cytokines in osteoblast-conditioned medium promote the migration of breast cancer cells

Bone is one of the most common metastatic sites for breast cancer. In this study, we observed a promoting effect of osteoblast-conditioned medium (OCM) on the migration of MCF-7, a noninvasive cell line of breast cancer cells. Cytokine antibody array was used to compare the cytokines of OCM with the conditioned medium of non-differentiated osteoblast cells, which consequently revealed factors related to migration, such as IL8, IL6, CSF2 (G-CSF), CSF3 (GM-CSF), and TNFRSF11B (osteoprotegerin). The expression of genes related to migration was also estimated with a PCR array, which showed that 9 genes were upregulated and 26 genes downregulated. Moreover, activated p38, ERK, and AKT pathways were found in the OCM treatment group. This finding indicated the migration ability of breast cancer cells, which move toward the bone depending on the presence of specific cytokines in its surrounding microenvironment.

The rise of testicular germ cell tumours: the search for causes, risk factors and novel therapeutic targets

Since the beginning of the 20th century there has been a decline in the reproductive vitality of men within the Western world. The declining sperm quantity and quality has been associated with increased overt disorders of sexual development including hypospadias, undescended testes and type II testicular germ cell tumours (TGCTs). The increase in TGCTs cannot be accounted for by genetic changes in the population. Therefore exposure to environmental toxicants appears to be a major contributor to the aetiology of TGCTs and men with a genetic predisposition are particularly vulnerable. In particular, Type II TGCTs have been identified to arise from a precursor lesion Carcinoma in situ (CIS), identified as a dysfunctional gonocyte; however, the exact triggers for CIS development are currently unknown. Therefore the transition from gonocytes into spermatogonia is key to those studying TGCTs. Recently we have identified seven miRNA molecules (including members of the miR-290 family and miR-136, 463* and 743a) to be significantly changed over this transition period. These miRNA molecules are predicted to have targets within the CXCR4, PTEN, DHH, RAC and PDGF pathways, all of which have important roles in germ cell migration, proliferation and homing to the spermatogonial stem cell niche. Given the plethora of potential targets affected by each miRNA molecule, subtle changes in miRNA expression could have significant consequences e.g. tumourigenesis. The role of non-traditional oncogenes and tumour suppressors such as miRNA in TGCT is highlighted by the fact that the majority of these tumours express wild type p53, a pivotal tumour suppressor usually inactivated in cancer. While treatment of TGCTs is highly successful, the impact of these treatments on fertility means that identification of exact triggers, earlier diagnosis and alternate treatments are essential. This review examines the genetic factors and possible triggers of type II TGCT to highlight target areas for potential new treatments.

Insulin-like growth factor binding protein 7, a member of insulin-like growth factor signal pathway, involved in immune response of small abalone Haliotis diversicolor

Insulin-like growth factor binding protein 7 (IGFBP7), the only member of the IGFBP superfamily that binds strongly to insulin, may have different functions from other IGFBPs. Unlike other IGFBPs, there is no knowledge available on aquatic invertebrate IGFBP7. In this study, a molluscan IGFBP7 gene, saIGFBP7, was cloned for the first time from the small abalone Haliotis diversicolor. Its full-length cDNA sequence is 1812 bp, with a 720 bp open reading frame encoding a protein of 239 aa. The molecular mass of the deduced protein is approximately 25.37 kDa with an estimated pI of 5.00, and it shares highest 41% identity to IGFBP7 of Amblyomma americanum. Analysis of conserved domains revealed the presence of an IGFBP N-terminal domain (IB), a kazal-type serine proteinase inhibitor domain (KI), and an immunoglobulin-like C2 domain (IgC2) in saIGFBP7. Furthermore, the 12 cysteine residues and the signature amino acid motif 'xCGCCxxC' which are characterized by the amino terminus region of the IGFBP superfamily are all presented in saIGFBP7. Quantitative real-time PCR and western blot were employed to investigate the tissue distribution of saIGFBP7, and its expression under bacterial challenge. The saIGFBP7 mRNA and protein could be detected in all examined tissues, with the highest expression level in hemocytes, higher expression level in gills, and was up-regulated in hemocytes and gills after bacterial injection. In addition, saIGFBP7 mRNA transcripts were observed in a subset of the branchial epithelium and the nucleus of hemocytes using the in situ hybridization method. Interestingly, saIGFBP7 was detected mainly in the goblet-like cell of the branchial epithelium by immunohistochemistry. These results suggested that saIGFBP7 was likely to be involved in a function associated with pathogenic infection and may play an important role in the adult abalone immune system.

IGFBP7 participates in the reciprocal interaction between acute lymphoblastic leukemia and BM stromal cells and in leukemia resistance to asparaginase

The interaction of acute lymphoblastic leukemia (ALL) blasts with bone marrow (BM) stromal cells (BMSCs) has a positive impact on ALL resistance to chemotherapy. We investigated the modulation of a series of putative asparaginase-resistance/sensitivity genes in B-precursor ALL cells upon coculture with BMSCs. Coculture with stromal cells resulted in increased insulin-like growth factor (IGF)-binding protein 7 (IGFBP7) expression by ALL cells. Assays with IGFBP7 knockdown ALL and stromal cell lines, or with addition of recombinant rIGFBP7 (rIGFBP7) to the culture medium, showed that IGFBP7 acts as a positive regulator of ALL and stromal cells growth, and significantly enhances in-vitro resistance of ALL to asparaginase. In these assays, IGFBP7 function occurred mainly in an insulin- and stromal-dependent manner. ALL cells were found to contribute substantially to extracellular IGFBP7 levels in the conditioned coculture medium. Diagnostic BM plasma from children with ALL had higher levels of IGFBP7 than controls. IGFBP7, in an insulin/IGF-dependent manner, enhanced asparagine synthetase expression and asparagine secretion by BMSCs, thus providing a stromal-dependent mechanism by which IGFBP7 protects ALL cells against asparaginase in this coculture system. Importantly, higher IGFBP7 mRNA levels were associated with lower leukemia-free survival (Cox regression model, P=0.003) in precursor B-cell Ph(-) ALL patients (n=147) treated with a contemporary polychemotherapy protocol.

The role of insulin-like growth factor-I in the physiopathology of hearing

Insulin-like growth factor-I (IGF-I) belongs to the family of polypeptides of insulin, which play a central role in embryonic development and adult nervous system homeostasis by endocrine, autocrine, and paracrine mechanisms. IGF-I is fundamental for the regulation of cochlear development, growth, and differentiation, and its mutations are associated with hearing loss in mice and men. Low levels of IGF-I have been shown to correlate with different human syndromes showing hearing loss and with presbyacusis. Animal models are fundamental to understand the genetic, epigenetic, and environmental factors that contribute to human hearing loss. In the mouse, IGF-I serum levels decrease with aging and there is a concomitant hearing loss and retinal degeneration. In the Igf1(-/-) null mouse, hearing loss is due to neuronal loss, poor innervation of the sensory hair cells, and age-related stria vascularis alterations. In the inner ear, IGF-I actions are mediated by intracellular signaling networks, RAF, AKT, and p38 MAPK protein kinases modulate the expression and activity of transcription factors, as AP1, MEF2, FoxM1, and FoxP3, leading to the regulation of cell cycle and metabolism. Therapy with rhIGF-I has been approved in humans for the treatment of poor linear growth and certain neurodegenerative diseases. This review will discuss these findings and their implications in new IGF-I-based treatments for the protection or repair of hearing loss.

Microarray analysis in a cell death resistant glioma cell line to identify signaling pathways and novel genes controlling resistance and malignancy

Glioblastoma multiforme (GBM) is a lethal type of cancer mainly resistant to radio- and chemotherapy. Since the tumor suppressor p53 functions as a transcription factor regulating the expression of genes involved in growth inhibition, DNA repair and apoptosis, we previously assessed whether specific differences in the modulation of gene expression are responsible for the anti-tumor properties of a dominant positive p53, chimeric tumor suppressor (CTS)-1. CTS-1 is based on the sequence of p53 and designed to resist various mechanisms of inactivation which limit the activity of p53. To identify CTS-1-regulated cell death-inducing genes, we generated a CTS-1-resistant glioma cell line (229R). We used Affymetrix whole-genome microarray expression analysis to analyze alterations in gene expression and identified a variety of CTS-1 regulated genes involved in cancer-linked processes. 313 genes were differentially expressed in Adeno-CTS-1 (Ad-CTS-1)-infected and 700 genes in uninfected 229R cells compared to matching parental cells. Ingenuity Pathway Analysis (IPA) determined a variety of differentially expressed genes in Ad-CTS-1-infected cells that were members of the intracellular networks with central tumor-involved players such as nuclear factor kappa B (NF-κB), protein kinase B (PKB/AKT) or transforming growth factor beta (TGF-β). Differentially regulated genes include secreted factors as well as intracellular proteins and transcription factors regulating not only cell death, but also processes such as tumor cell motility and immunity. This work gives an overview of the pathways differentially regulated in the resistant versus parental glioma cells and might be helpful to identify candidate genes which could serve as targets to develop novel glioma specific therapy strategies.

Dinosaurs and ancient civilizations: reflections on the treatment of cancer

Research efforts in the area of palaeopathology have been seen as an avenue to improve our understanding of the pathogenesis of cancer. Answers to questions of whether dinosaurs had cancer, or if cancer plagued ancient civilizations, have captured the imagination as well as the popular media. Evidence for dinosaurian cancer may indicate that cancer may have been with us from the dawn of time. Ancient recorded history suggests that past civilizations attempted to fight cancer with a variety of interventions. When contemplating the issue why a generalized cure for cancer has not been found, it might prove useful to reflect on the relatively limited time that this issue has been an agenda item of governmental attention as well as continued introduction of an every evolving myriad of manmade carcinogens relative to the total time cancer has been present on planet Earth. This article reflects on the history of cancer and the progress made following the initiation of the "era of cancer chemotherapy."