As a hormone with a number of biological effects, insulin not only displays the function of classic metabolic regulation, but also can regulate cell proliferation and differentiation, and ensure growth and development of embryos and young individuals. In vitro insulin can stimulate cell proliferation and differentiation. Insulin is also an important growth regulator in vivo, which has been proved in more and more studies. The role of insulin at the cellular level is triggered by the binding of insulin to its receptor located in the cell surface. However, insulin at the higher concentration can also been triggered by insulin-like growth factor-1 (IGF-1) receptor. Its role varies in different cell lines. Insulin receptor and insulin-like growth factor receptor-1 are widely expressed in human MDS and AML cell membranes. Recently, many studies related to the relationship between hyperinsulinemia and cancer have been reported. In this review the role and its possible mechanism in promoting human leukemia cell proliferation and inhibiting human leukemia cell proliferation are summarized. Furthermore, the potential application prospect of insulin analogues also will be described.
Cell Differentiation ; drug effects ; Cell Proliferation ; drug effects ; Humans ; Insulin ; pharmacology ; Leukemia ; metabolism ; pathology ; Receptor, IGF Type 1 ; metabolism ; Receptor, Insulin ; metabolism

This study was aimed to explore the effects of insulin on expression of insulin receptor (IR) and insulin-like growth factor-I receptor (IGF-IR) in Reh cells and promoting effect on proliferation of Reh cells. The proliferation of Reh cells were evaluated by CCK-8 assay. The expression levels of IR and IGF-IR mRNA in Reh cells at different times were detected by real-time quantitative polymerase chain reaction. The results showed that insulin promoted the proliferation of Reh cells in dose- and time-dependent manners. Compared with the control group, insulin promoted the proliferation of Reh cells obviously (P < 0.05). When Reh cells were treated with insulin 10(-9) mol/L for 24, 48 and 72 h, the relative quantity of IR expression (2(-ΔCt1)/2(-ΔCt2)) was 2.2520 ± 0.7431, 1.9956 ± 0.9692 and 3.9766 ± 1.3189, respectively, the relative quantity of IGF-IR expression was 1.0803 ± 0.2238, 1.6026 ± 0.6158 and 3.1013 ± 0.1008, respectively, compared with the control group. The expression levels of IR and IGF-IR mRNA in Reh cells treated with insulin were obviously increased compared with the control group. It is concluded that insulin promotes the proliferation of Reh cells. The high expression levels of IR and IGF-IR may closely related with the growth of leukemia cells.
Cell Line, Tumor ; Cell Proliferation ; drug effects ; Humans ; Insulin ; pharmacology ; Leukemia, Lymphoid ; metabolism ; pathology ; Receptor, IGF Type 1 ; metabolism ; Receptor, Insulin ; metabolism

OBJECTIVETo investigate the therapeutic value of inhibiting the expression of insulin-like growth factor-I receptor (IGF-IR) using picropodophyllin (PPP) by studying the effects on proliferative and metastatic potentials of human hepatocellular carcinoma (HCC) using an in vitro cultured cell system.

METHODSIGF-IR expression in human HCC cell lines (Bel-7404, Bel-7402, HepG2, and Huh-7) and human hepatocytes (L02) was assessed at baseline (pre-treatment) and after PPP treatment by western blotting. Changes in cell cycle were analyzed by flow cytometry and in cell viability by sulforhodamine B staining. Early apoptosis was detected by annexin-V/FITC and propidium iodide double-staining assay. Caspase-3/7 activity was suppressed by z-VAD-FMK and analyzed by homogeneous luminescence assay. Effects on cell motility were tested by wound-scratch test. Between-group differences were assessed by t-test or one-way analysis of variance.

RESULTSIGF-IR was markedly up-regulated in all HCC cell lines (vs. non-hepatoma hepatocytes). HCC cells with PPP-inhibited IGF-IR showed time-dependent decreases in cell motility and viability. After treatment with PPP for 24 hours, the proportion of HCC cells in G1 phase was 2.1% +/- 0.4%, in S phase was 11.0% +/- 0.7%, and in G2/M phase was 87.1% +/- 0.6%, and no healing was observed in the wound-scratch assay. The PPP treatment induced cell apoptosis, as evidenced by enhanced caspase-3/7 activity; the proportion of annexin-V+/PI- cells was significantly higher in the HepG2 cells than in the non-hepatoma hepatocytes (16.4% +/- 0.4% vs. 5.8% +/- 0.2%, t = 14.05, P less than 0.01). After z-VAD-FMK treatment, the apoptosis rate was significantly higher in the HepG2 cells than in the non-hepatoma hepatocytes (11.3% +/- 0.7% vs. 5.8% +/- 0.2%, t = 11.83, P less than 0.01).

CONCLUSIONIGF-IR is associated with proliferation, cell motility, and apoptosis of HCC cells, and may be a promising molecular target for HCC.

Apoptosis ; drug effects ; Carcinoma, Hepatocellular ; metabolism ; pathology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Humans ; Liver Neoplasms ; metabolism ; pathology ; Podophyllotoxin ; analogs & derivatives ; pharmacology ; Receptor, IGF Type 1 ; metabolism

OBJECTIVETo evaluate the effect of insulin-like growth factor (IGF) and its receptor-I antibody on the growth of human adrenocortical carcinoma SW-13 cell line in vitro.

METHODThe growth curves of SW-13 cell treated with IGF and its receptor-I antibody were obtained by means of MTT assay. The effects of the two agents, added either alone or in combination at different concentrations, on the cell growth were evaluated.

RESULTSIGF significantly promoted proliferation of SW-13 cells, and its effect was positively correlated with its concentrations (P<0.05). IGF receptor-I antibody inhibited the effect of insulin-like growth factor with direct inhibitory effect on proliferation of SW-13 cells (P<0.05).

CONCLUSIONIGF can promote the growth of human adrenocortical carcinoma SW-13 cells via its receptor-I. IGF receptor-I antibody can inhibit the effect of the growth factor, suggesting a possible role of this receptor in the treatment of adrenocortical carcinoma.

Adrenocortical Carcinoma ; pathology ; Antibodies ; pharmacology ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Dose-Response Relationship, Drug ; Humans ; Insulin-Like Growth Factor I ; pharmacology ; Receptor, IGF Type 1 ; immunology

BACKGROUND/AIMS: Statins act as antineoplastic agents through the inhibition of cell proliferation. This study sought to demonstrate the effects of statins on extrahepatic bile duct cancer cell apoptosis and to document the changes in protein expression involved in tumor growth and suppression. METHODS: Human extrahepatic bile duct cancer cells were cultured. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays were performed to determine the effect of statins on cell proliferation. Apoptosis was measured by a cell death detection enzyme-linked immunosorbent assay and caspase-3 activity assay, and flow cytometry was used to determine the percentage of cells in each phase of the cell cycle. The protein expression of Bax, Bcl-2, insulin-like growth factor 1 (IGF-1) receptor, extracellular signal-regulated kinase 1/2 (ERK1/2), and Akt was measured by Western blot analysis. RESULTS: Simvastatin suppressed cell proliferation by inducing G1 phase cell cycle arrest in bile duct cancer cells. Furthermore, it induced apoptosis via caspase-3 activation, downregulated the expression of the Bcl-2 protein, and enhanced the expression of the Bax protein. Moreover, simvastatin suppressed the expression of the IGF-1 receptor and IGF-1-induced ERK/Akt activation. CONCLUSIONS: Simvastatin induces apoptosis in bile duct cancer cells, which suggests that it could be an antineoplastic agent for bile duct cancer.
Antineoplastic Agents/pharmacology ; Apoptosis/*drug effects ; Bile Duct Neoplasms/*drug therapy ; Cell Cycle/drug effects ; Cell Line, Tumor ; Cell Proliferation/drug effects ; Enzyme-Linked Immunosorbent Assay ; Flow Cytometry ; Humans ; Hypolipidemic Agents/*pharmacology ; Receptor, IGF Type 1/*drug effects ; Simvastatin/*pharmacology

OBJECTIVETo explore the mechanism of Er'zhi Tiangui Granule (ETG) in improving the quality of oocyte.

METHODSNinety mice were randomly divided into 6 groups. The number of high-quality oocytes was comparatively observed in the 1st experimental group and the 1st control group; the embryonic cleavage rate was observed in the 2nd experimental group and the 2nd control group and the quantity of insulin-like growth factor-1R mRNA (IGF-1R mRNA) expression in ovarian granular cells was determined by using in situ hybridization in the 3rd experimental group and the 3rd control group.

RESULTSThe high-quality oocytes rate, the embryonic cleavage rate and the quantity of IGF-1R mRNA expression in the three paired groups was (78 +/- 8)% vs (71 +/- 5)%, (88 +/- 3)% vs (83 +/- 5)%, 0.4890 +/- 0.0454 vs 0.4439 +/- 0.0283, respectively. The difference between the experimental groups to the respective control groups was significant (all P < 0.05), and positive correlation was shown between the high-quality oocytes rate and the quantity of IGF-1R mRNA expression.

CONCLUSIONThe mechanism of ETG in improving the quality of oocyte may be related with the elevation of IGF-1R mRNA level in ovarian granular cells.

Animals ; Cleavage Stage, Ovum ; physiology ; Drugs, Chinese Herbal ; pharmacology ; Female ; Gene Expression ; Male ; Mice ; Oocytes ; drug effects ; physiology ; Ovary ; metabolism ; RNA, Messenger ; biosynthesis ; genetics ; Random Allocation ; Receptor, IGF Type 1 ; biosynthesis ; genetics

The importance of insulin-like growth factor 1 receptor (IGF-1R) signaling in malignant behaviour of tumour cells is well established. Inhibiting the activity of IGF-1R may result in striking apoptosis in malignant cells growing. IGF-1R antibodies which are currently in phase I and II clinical trials and several IGF-IR TKIs have preclinically been characterized. This review describes recent developments of small molecule tyrosine kinase inhibitors.
Animals ; Apoptosis ; drug effects ; Benzimidazoles ; pharmacology ; Catechin ; analogs & derivatives ; pharmacology ; Cell Line, Tumor ; Humans ; Neoplasms ; pathology ; Piperazines ; pharmacology ; Protein Kinase Inhibitors ; pharmacology ; Pyridones ; pharmacology ; Pyrimidines ; pharmacology ; Pyrroles ; pharmacology ; Receptor, IGF Type 1 ; antagonists & inhibitors ; chemistry ; metabolism ; Signal Transduction

PTEN/MMAC1 is a tumor suppressor gene that is mutated in a variety of advanced and metastatic cancers. Its major function is likely to be the phosphatase activity that regulates the phosphotidylinositol (PI)3-kinase/ Akt pathway. On the other hand, IGF system plays an important role in cell proliferation and cell survival via PI3-kinase/Akt and mitogen-activated protein kinase pathways in many cancer cells. To evaluate effect of PTEN on cell growth and IGF system in gastric cancer, human gastric adenocarcinoma cells (SNU-5 & -216) were transfected with human PTEN cDNA. Those PTEN- transfected gastric cancer cells had a lower proliferation rate than the pcDNA3-transfected cells. PTEN overexpression induced a profound decrease in the IGF-II and IGF-IR expression levels, and downregulation of IGF-II expression by PTEN was mediated through the regulation of the IGF-II promoter. In addition, a PI3-kinase inhibitor, LY294002, induced the downregulation of IGF-II expression. The PTEN-overexpressing SUN-5 and -216 cells were more sensitive to death induced by etoposide and adriamycin that induce DNA damage than the pcDNA3-transfected cells. These findings suggest that PTEN suppresses the cell growth through modulation of IGF system and sensitizing cancer cells to cell death by anticancer drugs.
Antineoplastic Agents/*pharmacology ; Cell Line, Tumor ; Cell Proliferation/drug effects ; *Down-Regulation ; Humans ; Insulin-Like Growth Factor II/*genetics/*metabolism ; PTEN Phosphohydrolase/genetics/*metabolism ; Receptor, IGF Type 1/genetics/metabolism ; Research Support, Non-U.S. Gov't ; Stomach Neoplasms/*genetics/metabolism/*pathology

OBJECTIVETo investigate the effect of Chinese herbs for nourishing yin and removing fire (NYRF) on gene expressions of estrogen receptor alpha (ER alpha), insulin-like growth factor-1 receptor (IGF-1R) and epithelial growth factor receptor (EGFR) in the epiphyseal growth plate of the female pubertal rats.

METHODSThe rats were randomly divided into the control group and the intervened group. Immunohistochemistry and realtime-PCR methods were used to measure the gene expression of ER alpha, IGF-1R and EGFR and their protein synthesis in epiphyseal growth plate.

RESULTSAfter being intervened with NYRF, the gene expressions of ER alpha and IGF-1R were down-regulated and their protein synthesis markedly reduced, while those of EGFR were unchanged.

CONCLUSIONNYRF can modulate the development and maturation of bone by regulating the expressions of ER alpha and IGF-1R in the epiphyseal growth plate.

Animals ; Disease Models, Animal ; Drugs, Chinese Herbal ; pharmacology ; Estrogen Receptor alpha ; genetics ; metabolism ; Female ; Gene Expression ; drug effects ; Growth Plate ; drug effects ; metabolism ; Humans ; Protein Biosynthesis ; drug effects ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Receptor, Epidermal Growth Factor ; genetics ; metabolism ; Receptor, IGF Type 1 ; genetics ; metabolism ; Yin-Yang

OBJECTIVETo investigate the effects and the mechanisms of stanozolol (ST) on the proliferation, maturation and differentiation of in vitro cultured growth plate chondrocyte isolated from gonadotropin releasing hormone analogue (GnRHa)-treated adolescent rats, to study if ST mediates the proliferation of chondrocytes via the estrogen receptor alpha (ERalpha), androgen receptor (AR) and/or insulin-like growth factor-1 receptor (IGF-1R) and interactions of the two receptor and IGF-1R receptor signaling pathway, to investigate the mechanism of the biological effects in ST promoting bone growth/maturity at molecular level.

METHODThe rats were weaned at the end of 3 weeks and intramuscular injection of triptorelin of GnRHa preparations, qow x 2 was started. The rats were sacrificed at the end of 7 weeks, and then the tibiae growth plates were taken out with sterile procedure. The chondrocytes were obtained by two-time enzyme digestion method, and the experiments were carried out with the primary chondrocytes. Immunohistochemical staining of proliferating cell nuclear antigen (PCNA) and Western blot analysis were applied.

RESULTThe results of PCNA demonstrated that stanozolol enhanced the proliferation of the chondrocytes, time-course studies showed that the proliferation were maximally stimulated by stanozolol after 2 days of incubation and decreased again after longer periods of incubation. The expression of p-ERalpha, p-IGF-1R and p-extracellular-signal regulated kinase 1/2 (ERK1/2) increased with the incubation period of ST treatment, and reached the peak value at a certain time, and then gradually decreased. The expression of p-ERalpha, p-IGF-1R and p-ERK1/2 increased with the elevation of ST concentration, and reached the peak value at 10(-9) - 10(-8) mol/L, then gradually decreased. ST induced-p-ERalpha expression was partially blocked by ERalpha and mitogen-activated protein kinase kinase inhibitors. ST induced-p-IGF-1R expression was partially blocked by ERalpha and IGF-1R inhibitors. ST induced-p-ERK1/2 expression was partially blocked by mitogen-activated protein kinase kinase and IGF-1R inhibitors.

CONCLUSIONAs an androgen derivation, ST exerts its biological effects of promoting proliferation of the long bone growth plate chondrocytes via activating the classic ERalpha receptor pathway and mitogen-activated protein kinase pathway, and at the same time, by activation of IGF-1R. Both IGF-1R and ERalpha can promote "cross-talk" of two systems' receptor signal through mitogen-activated protein kinase signal pathway.

Androgens ; pharmacology ; Animals ; Cells, Cultured ; Chondrocytes ; cytology ; drug effects ; metabolism ; Estrogen Receptor alpha ; metabolism ; Female ; Growth Plate ; drug effects ; metabolism ; Mitogen-Activated Protein Kinase 3 ; metabolism ; Rats ; Receptor Cross-Talk ; Receptor, IGF Type 1 ; metabolism ; Signal Transduction ; drug effects ; Stanozolol ; pharmacology