Objective To establish a stable colorectal cancer model in liver specific insulin-like growth factor (IGF)-1 deficient (LID) mice and examine the potential relationship between IGF-1 level and risk of mice constitutional colorectal cancer. Methods ①Establishment of a colorectal cancer model: The LID mice, in which IGF-1 level in circulation was 25% of BALB/c mice. Induction of colorectal cancer was achieved by using the 1,1 Dimethylhydrazine (DMH) with hypodermic injection at transverse part. ②Eighty fresh samples of cancer tissues and adjacent tissues were obtained from LID mice (experimental group) and BALB/c mice (control group). The expression of IGF-1 was studied by immunohistochemical assay (SP method). Results ①Weight loss occurred in both experimental group and control group after injection. Compared with the body weight before injection on 18 weeks and 24 weeks in each group, there were significant differences after injection at the same phase in each group (P＜0.05). ②The results of IGF-1 expression in cancer tissues and adjacent tissues: IGF-1 got a diffuse distribution in cancer cell cytoplasm. The positive expressions of IGF-1 in the cancer tissues and their adjacent cancer tissues were 6/7, 2/7 and 13/16, 7/16 respectively in experimental group and control group. There were significant differences between the cancer tissues and adjacent tissues inside both groups (P＜0.05). There were no significant differences inside both of cancer tissues and adjacent tissues respectively between experimental group and control group (Pgt;0.05). Conclusion In the established colorectal cancer model by DMH, IGF-1 plays an important role in the development and progression of colorectal cancer.
Objective To investigate the relationship between the level of serum-insulin like growth factor-1( IGF-1) and the nut ritional status of cancerous cachexia. Methods Colon cancer CT-26 cells were implanted subcutaneously to 30 liver2specified IGF-1 gene deleted (L ID) C57BL/ 6 mice to establish cancerous cachexia model and theother 30 C57BL/ 6 mice were included as cont rol group. The serum levels of IGF-1 , cytokine TNF-αand IL-6 , bloodglucose , albumin and t riglyceride were detected respectively on day 14 , 18 and 22 af ter the plantation of tumor. Thebody weight of mice , tumor weight and the weight af ter tumor removed in two group s were measured respectively.Results Af ter the plantation , the levels of IGF-1 in L ID group at different times were all significantly lower thanthose in cont rol group ( Plt; 0. 05) . The serum levels of TNF-α, IL-6 , blood glucose and t riglyceride were ascendinggradually over time ( Plt; 0. 05) , but weight s af ter tumor removed and the level of albumin were descending in twogroup s ( Plt; 0. 05) . Compared with the cont rol group , the serum levels of IL-6 , TNF-α, blood glucose and t riglyceride in L ID tumor-bearing mice were all significantly higher at different time point s ( P lt; 0. 05) . On day 18 and 22 ,the weight s af ter tumor removed and the amount of ingestion in L ID group were significantly lower than those in thecont rol group ( Plt; 0. 05) . Conclusion Compared with the low level of IGF-1 in cancerous cachexia , normal level ofserum IGF-1 may represent lower degree of cancerous cachexia2related cytokines and better nut ritional state , whichmay provide a novel idea of the therapy of cancerous cachexia.
OBJECTIVE: To investigate the effect of combined treatment of recombinant human growth hormone (rhGH) and insulin-like growth factor-1 (IGF-1) on wound healing and protein catabolism in burned rats. METHODS: Forty Wistar rats with deep II degree scald injury were divided randomly into four groups and received rhGH (0.1 U/kg.d), rhGH (0.1 U/kg.d) plus IGF-1 (2.0 mg/kg.d), IGF-1 (2.0 mg/kg.d) and Ringer’s solution (2 ml/kg.d, as control group) respectively. The wound healing time and protein catabolism levels of every groups were compared after 2 weeks. RESULTS: Total body weight began to increase after 2 weeks in rhGH group and rhGH plus IGF-1 group, but in control group, it was occurred after 4-5 weeks. The body weight of rhGH plus IGF-1 group was 1.65 times than that of rhGH group. The wound healing time in rhGH plus IGF-1 group (17.1 +/- 4.4) days was significantly lower than that of rhGH (20.5 +/- 4.8) days and control group (29.7 +/- 6.3) days. The protein level of rhGH plus IGF-1 group was significantly higher than that of control group and rhGH group. CONCLUSION: It suggests that rhGH plus IGF-1 with synergism is more effective in promoting wound healing and increasing the protein catabolism.
Objective To investigate the impacts of neoadjuvant chemotherapy on the expression of insulin-like growth factor-1 receptor (IGF-1R) and on operation procedure and the significance of prognosis. Methods The expression of IGF-1R in 40 patients with breast cancer before and after neoadjuvant chemotherapy was measured by immunohistochemistry. The diagnosis was proved by core biopsy. All the patients took the TAC chemotherapy regimen. Modified radical operation was performed after two chemotherapy cycles and the IGF-1R expression was measured again. The clinical effect of neoadjuvant chemotherapy was assessed according to WHO criterion by measuring the size of tumor by physical examination and B type ultrasound. Results After neoadjuvant chemotherapy the tumor size shrank in 29 patients, there was no CR (complete response) or PD (progressed disease) to be documented. IGF-1R expression could be downregulated in 25 patients. Conclusion Neoadjuvant chemotherapy can inhibit the tumor growth by downregulation of the expression of IGF-1R.
Objective To investigate the expression of transforminggrowth factor β1(TGF-β1) and insulin-like growth factorⅠ(IGF-Ⅰ)in new bone after low frequency micromovement. Methods Fifteen female sheep from Shandong province were involved in the study and their bilateral tibias transversely osteotomized in the middle shafts with a defect of 2 mm.The hind limbs were fixed with unilateral external fixators connected to a controlled micromovement device. Ten days after osteotomy, one hind limb of each sheep randomlywas selected to perform micromovement at an amplitude of 0.25 mm and a frequency of 1 Hertz, 30 min a day for 4 weeks ( micromovement group). The other hindlimb served as the control group. Five sheep were sacrificed at 3,4 and 6 weeks after osteotomy, respectively, and specimens were harvested for detecting the expression of TGF-β1 and IGF-Ⅰby immunohistochemistry and RT-PCR. Results Immunohistochemistry: In the third postoperative week in the micromovement group, the expression of TGF-β1 was detected in different areas of new chondrocytes at the margin of callus, mainly in proliferating area, and IGF-Ⅰexpressed in osteoblasts at the margin of endochondral ossification area, calcified and mature chondrocytes and osteocytes. There was seldom expression ofIGF-Ⅰ and little expression of TGF-β1 in the corresponding area in the control one. In the 4th postoperative week in the micromovement group, theexpression of TGF-β1 diminished gradually with the mature of new bone and be located in extracellular matrix and osteoblasts around ossified areas; The expression ofIGF-Ⅰ reached the peak and be located mainly in osteoblasts of new bone surface, maturing osteocytes and calcifing osteoid. But there was little expression of them in the control group. In the sixth postoperative week in the micromovement group, there was a little expression of IGF-Ⅰ expression but little expression of TGF-β1; there was nearly no expression of them in the control group. In the micromovement group, the absorbance values of TGF-β1 at 3 and 4 weeksand of IGF-Ⅰat 3, 4 and 6 weeks were significantlyhigher than those in control group（P＜0.05）. RTPCR: In the third and fourth postoperative weeks in the micromovement group, there was higher expression of mRNA of TGF-β1 and TGF-I than those in control group; in the sixth postoperative week, the expression diminished gradually, but was higher than that in control group. The absorbance values of TGF-β1 at 3 and 4 weeks and IGF-Ⅰat 3, 4 and 6weeks were significantly higher than those of control group（P＜0.05）. Conclusion Low frequency and controlled micromovement in the early stage of the fracture healing can promote the expression of TGF-β1 and IGF-Ⅰ.They worked together to regulate the process of the endochondral ossification, while in the late stage the differentiation of osteocytes and mineralization of osteoid were regulated mainly by IGF-Ⅰ, which played an important role in regulating the cell biological behavior during micromovement.
ObjectiveTo investigate the relationship between insulin-like growth factor binding protein (IGFBP) gene with pancreatic cancer. MethodsThe relevant literatures at home and abroad in recent years were reviewed. From the pancreatic cancer related genes, IGFBP related tumors and the correlation between IGFBP and pancreatic cancer research and other aspects of the previous research results were summaried. ResultsMost of the studies suggested that IGFBP could inhibit the function of tumor cells through the IGF dependent pathway, but the deletion or mutation of IGFBP gene and its regulation mechanism are still unclear. ConclusionIGFBP is closely related to the tumor, but its specific effects and mechanism of pancreatic cancer has not been settled. In order to affect the degree of cell differentiation, regulation of tumor growth and metastasis probability through the change of endogenous IGFBP gene level, the further studie is needed.
Objective To investigate the ability of repairing bone defect with the compound of recombinant human insulinlike growth factor 1 (rhIGF-1), coralline hydroxyapatite(CHA) and autogeneous red bone marrow(ARBM), and to study the feasibility of the compounds being used as bone substitute materials. Methods Bilateral radius bone defects(11 mm in length) were created in 54 Chinese rabbits,which were randomly divided into 3 groups, and two different materials were randomly transplanted into the bilateral defects:in group 1, with material A(rhIGF-1/CHA/ARBM) and material B(CHA/ARBM); in group 2, with material C(rhIGF-1/CHA) and material D(CHA); in group 3, with E(autograft) and F(no implant) as controls. At 2, 4, 8 and 12 weeks, the effects were assessed by X-ray andimage analysis, biomechanics(at 12 weeks), as well as histological observation. Results X-ray and image analysis showed that material A of group 1was significantly superior to any other materials(P＜0.01). Antibending biomechanic detection showed that material A and Ewas significantly superior to the other materials(Plt;0.01), but no significant difference was found between A and E in the 12th week(Pgt;0.05). And by histological observation, in analogical bone morphological progress, materials C and D obviously inferior to materials A, B and E, but there was no significant difference between materials C and D. F had no evidence of new bone rebridging. Conclusion The recombinant compound CHA/ARBM(rhIGF-1),which posseses the potential ability of osteogenesis,osteoconduction and osteoinduction for bone defect repairing,can serve as a new type of autogenous bone substitute material.
Objective To explore the ability of insulin-like growth factor-Ⅰ (IGF-Ⅰ) and hyaluracan acid in prompting chondrogenesis of engineering cartilage tissue.Methods Human articular chondrocytes were isolatedand cultured in DMEM plus 10% fetal bovine serum. They were divided into three groups：hyaluracan acid+chondrocytes + IGF-Ⅰ group(IGF-Ⅰ group), hyaluracan acid+chondrocytes group(cell group), hyaluracan acid group(control group). The ability of chondrogenesis was investigated by HE and toluidine blue staining, human collagen Ⅱ immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR).Results Both cell group and IGF-Ⅰ group could develop into cartilage tissue in the sixth week while control group could not. The number of cartilage lacuna in IGF-Ⅰ group were more than that in cell group. Human collagen Ⅱ immunohistochemistry showed that there were ber positive cell in IGF-Ⅰ group than in cell group, collagen Ⅱ mRNA expression was more higher and collagen Ⅰ mRNA expression was lower in IGF-Ⅰ group than in cell group. Conclusion Insulin growth factorⅠ can prompt chondrogenesis of engineering cartilage tissue and ameliorate the quality of engineering cartilage tissue in vitro.
Objective To determine the effect of insulin-like growth factor-1 (IGF-1) on angiogenesis in mouse breast cancer model of lower and normal serum IGF-1 levels after using angiogenesis inhibitor ginsenoside Rg3 （GS Rg3）. Methods The breast cancer models were established in control mice and liver specific IGF-1 deficient (LID) mice by feeding DMBA and were treated with GS Rg3. Vascular endothelial growth factor (VEGF) and F8-RAg were detected by immunohistochemical method in breast cancer tissues. IGF-1 gene and angiogenesis relating genes were detected by gene chip in breast cancer and normal breast tissue. Results The incidence rate of breast cancer in LID mice was lower than that in control mice (P＜0.05). VEGF expression and microvessel density of LID mice were lower than those in control mice (P＜0.05). Compared to the control mice, IGF-1, FGF-1, TGF-β1 and HGF genes were increased, and FGFR-2, PDGF-A and PDGF-B genes were decreased in breast cancer of LID mice. After GS Rg3 treatment, VEGFa, EGF, EGFR, PDGF-A and FGFR-2 genes were increased, IGF-1 and TGF-β1 genes were decreased in breast cancer of LID mice compared with the control mice. Conclusion IGF-1 may be involved in mouse breast cancer progression and associated with the growth of blood vessels. Angiogenesis inhibitor may play an antitumor role by IGF-1 and TGF-β1.
Objective To probe the relationship between the levels of two hormone,growth hormone (GH) and insulin-I like growth factor-I(IGF-I),and diabetic retinopathy (DR) in the patients with noninsulindependent diabetic mellitus (NIDDM)． Methods The direct radioimmunoassay was used to determine GH and IGF-I in the serum of 38 normal cotrols,61 NIDDM patients without DR,77 patients with the simple DR and 48 patients with the proliferative DR．Difference among these groups were analysed and compared by the methods of t test,F test and correlation analysis． Results The results showed that the levels of GH and IGF-I in the patients with diabetes [GH(1.659plusmn;1.509)ng/ml，IGF-I(118.7plusmn;52.0) ng/ml] were significantly higher than those in the normal controls [GH(0.619plusmn;0.351)ng/ml，IGF-I (63.6plusmn;30.6) ng/ml)] (P＜0.01),and those in the DR group were higher than those in the NIDDM without retinopathy group (P＜0.01),and levels of GH and IGF-I in the proliferative DR group [GH(2.953plusmn;1.648) ng/ml，IGF-I (159.2plusmn;47.5) ng/ml] ) were significantly higher than those in the simple DR group [GH(1.742plusmn;1.523) ng/ml，IGF-I (123.6plusmn;40.6) ng/ml] (P＜0.01)．SeveritY of DR was positively correlated with the levels of GH and IGF-I(P＜0.01)． Conclusion The results indicate that GH and IGF-I levels in the serum of patients with diabetes might be correlated with mechanisms and development of DR． (Chin J Ocul Fundus Dis,2000,16:30-31)