Hepatocyte Growth Factor mRNA Levels Research Articles

Identification of Basophils as Source of Hepatocyte Growth Factor (HGF) In CML: a Potential Trigger of Disease Acceleration.

AbstractAbstract 1202Chronic myeloid leukemia (CML) is a myeloproliferative disorder in which BCR/ABL leads to enhanced survival of leukemic cells. Several different angiogenic molecules, including vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF), have been implicated in the pathogenesis of CML. Enhanced production of these pro-angiogenic molecules in CML may be associated with disease acceleration. However, little is known so far about the exact origin of these growth factors and about mechanisms underlying their production and secretion in CML cells. In the current study, we analyzed the cellular distribution of HGF and its receptor c-MET in CML cells, and explored the mechanism of expression of HGF in BCR/ABL-transformed cells. As assessed by immunostaining of bone marrow sections and isolated blood and bone marrow samples, the HGF protein was found to be expressed in a subset of leukemic cells in all patients tested. In addition, CML cells were found to express HGF mRNA and c-MET mRNA. In consecutive experiments, we were able to show that basophils are the primary source of HGF in CML. In particular, highly enriched sorted CD203c+ CML basophils were found to express substantial amounts of HGF mRNA as well as the HGF protein. Correspondingly, leukemic cell samples obtained from patients with accelerated phase CML were found to contain higher HGF mRNA levels compared to cells obtained from patients in chronic phase or blast phase CML. Finally, HGF mRNA and the HGF protein were detectable in the basophil-committed CML cell line KU812, but not in the more immature Ph+ cell line K562. We next asked whether expression of HGF in CML cells depends on BCR/ABL. To address this question, Ba/F3 cells with doxycycline-inducible expression of BCR/ABL were employed. However, BCR/ABL failed to induce expression of HGF mRNA or the HGF protein in Ba/F3 cells. Correspondingly, the BCR/ABL-blocker imatinib was found to inhibit expression of VEGF mRNA, but did not inhibit HGF mRNA expression in KU812 cells. Next, we examined the expression of c-MET in CML cells. c-MET mRNA was found to be expressed in KU812 and K562 cells, in highly enriched CD34+/CD38- CML stem cells, and less abundantly in more mature CD34+/CD38+ CML cells and CML basophils. The c-MET inhibitor MSC-2156119J-15 (Merck-Serono Darmstadt, Germany) was found to counteract growth of primary CML cells, K562 cells, and KU812 cells with comparable IC50 values (0.5-1.0 μM). In summary, our data suggest that HGF is a BCR/ABL-independent basophil-derived mediator in CML. Basophils and basophil-derived mediators may play a more active role in CML-acceleration as has been considered previously. Whether targeting of HGF or/and c-MET is an effective approach to block acceleration in CML remains to be elucidated. Disclosures:Valent:Novartis: Honoraria, Research Funding; Merck-Serono: Research Funding.

Adipose-Derived Stromal Cell Autologous Transplantation Ameliorates Pulmonary Arterial Hypertension Induced by Shunt Flow in Rat Models

Hyperkinetic pulmonary arterial hypertension (PAH) severely influences the success of operation for congenital heart disease and deteriorates the prognosis of disease. Adipose-derived stromal cell (ADSC) is a good alternative multipotent stem cell for regeneration medicine. PAH rat models were established by arteriovenous shunt and ADSCs were isolated, cultured, and labeled in vitro. Twelve weeks after shunt operation, rats received an injection of 5 × 10(7) ADSCs. Two weeks after transplantation, hemodynamic abnormality induced by the shunt flow and the hypertrophy of right ventricle were reversed, which was confirmed by invasive measurement and echocardiography examination. The PAH rats receiving cell transplantation demonstrated decreased remodeling of small arteries in the lung; immunohistochemistry analysis showed augmented expression of hepatocyte growth factor (HGF) and increased number of pulmonary small arteries. Western blot and real-time reverse transcriptase-polymerase chain reaction indicated that the protein and mRNA levels of HGF and endothelial nitric oxide synthase increased, respectively, in the lung after cell transplantation. Our results suggested that ADSC transplantation can ameliorate PAH induced by shunt flow by enhancing the expression of HGF and subsequently promoting angiogenesis in the injured lung tissue.

The HGF/c-Met signaling pathway in Hodgkin lymphoma

Abstract Abstract 1551 Poster Board I-574 Introduction Hodgkin lymphoma (HL) is a B-cell neoplasm characterized by a minority of neoplastic cells, the so-called Hodgkin and Reed-Sternberg (HRS) cells, which are located within an extensive infiltrate of reactive cells. Aberrant signaling of various receptor tyrosine kinases (RTKs) via autocrine or paracrine mechanisms contributes to the survival and proliferation of HRS cells. Activation of the hepatocyte growth factor (HGF)/c-Met signaling pathway has been implicated in the pathophysiology of many cancers, but its role in HL is poorly investigated. In this study, we investigated the expression of c-Met and HGF in HL patient tissues and studied the cell physiological effects of the HGF/c-Met signaling pathway using a c-Met tyrosine kinase inhibitor SU11274 in HL cell lines. Methods The expression of c-Met and HGF in HL patient tissues was studied by immunohistochemistry on a HL tissue microarray. The c-Met expression level was determined by Western blotting, while HGF mRNA and protein levels were measured by quantitative (q)RT-PCR and ELISA in four HL cell lines, i.e. L428, KMH2, L1236 and U-HO1. The effects of SU11274 treatment on the activity of the HGF/c-Met signaling pathway was determined by detection of phosphorylated downstream targets by Western blotting. Effects on cell growth and cell cycle were determined by 3-(4,5- Dimethylthiazol -2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay and by flow cytometry with Propidium iodide (PI), respectively. Results C-Met was detected in HRS cells in 55% (26/47) of HL patient tissues. Expression of HGF was detected in HRS cells in 5 c-Met positive and 2 c-Met negative HL patient tissues. C-Met was highly expressed in L428 compared to three other HL cell lines, whereas HGF was highly expressed in KMH2 and not or only weakly in the other three HL cell lines. Detectable levels of phosphorylated c-Met (p-Met) were observed only in L428 consistent with the high basal expression level of c-Met. Phosphorylation of c-Met, Akt and Erk1/2 were upregulated upon HGF stimulation of L428 cells. This activation could be blocked by inhibiting c-Met activation with SU11274. In functional studies, SU11274 suppressed cell growth in L428, promoted G2/M cell cycle arrest after 24h incubation, and induced tetraploidy after 48h. Washing of the cells after induction of G2/M arrest resulted in normal cell cycle progression indicating that the G2/M cell cycle arrest was reversible. Inhibition of PI3K, MEK1/2 and Erk1/2, three downstream targets of the HGF/c-Met signaling pathway, also induced G2/M cell cycle arrest in L428, indicating that these factors are involved in the G2/M cell cycle arrest induced by SU11274. Conclusion Co-expression of c-Met and HGF in HRS cells was observed in 11% of the HL patient tissues and HGF/c-Met signaling pathway regulates cell growth and cell cycle progression in L428 cells. Disclosures No relevant conflicts of interest to declare.

Changes in islet microvasculature following streptozotocin-induced β-cell loss and subsequent replacement in the neonatal rat

Neonatal rats undergo considerable beta-cell regeneration after depletion with streptozotocin (STZ). Since the intraislet vasculature is necessary for both beta-cell growth and function, we examined changes in vascular morphology following STZ. Neonatal Wistar rats (4 days) were injected with 70 mg/kg STZ, or buffer, and were examined between days 4 and 40 postinjection. Animals receiving STZ were relatively hyperglycemic for eight days, but became normoglycemic subsequent to a partial recovery of beta-cell mass. However, glucose tolerance remained impaired. The intraislet area occupied by capillaries was significantly reduced by approximately 20% following STZ, mainly within the beta-cell-rich islet core, but had recovered by day 40. Vascular endothelial growth factor (VEGF) was localized to beta-cells, and pancreatic VEGF mRNA levels in control animals showed a progressive increase between days 4 and 20. This rise was delayed following STZ, but by day 20 VEGF mRNA abundance exceeded that in control pancreas. Hepatocyte growth factor (HGF) was localized to intraislet endothelial cells. Levels of HGF mRNA increased until day 16 in control rats, but subsequently declined to low levels. Following STZ, HGF mRNA had declined prematurely after day 12. Type IV collagen was localized to the extracellular matrix around the intraislet vasculature. The islet area immunopositive for collagen was significantly reduced at all times following STZ. Results indicate that there is a relative loss of intraislet vasculature following STZ, which may limit subsequent beta-cell regeneration through both local growth factor and extracellular matrix interactions.

Met Over-Expression Is a Prognostic Factor for Myeloma Patients Treated with Novel Agents.

Abstract 1821Poster Board I-847 BackgroundOver-expression of the tyrosine kinase receptor Met has been reported in several solid tumors and increases cell proliferation, cell migration (scattering) and neoplastic angiogenesis. The Hepatocyte Growth Factor (HGF) is the only known Met ligand and the HGF/Met pathway seems to play a pivotal role in Multiple Myeloma (MM) pathogenesis. HGF is secreted by bone marrow stromal cells and Met is expressed at the surface of malignant plasma cells and endothelial cells. The phosphorylation of Met induced by HGF is a strong signal for cell growth and migration. The activity of the HGF/Met pathway and the heterogeneity of HGF/Met expression on MM cells suggest that the over-expression of Met could be a prognostic marker in MM patients. AimsTo investigate the role of HGF/Met pathway as prognostic marker predictive of response rate, progression-free survival (PFS) and overall survival (OS) in MM patients treated with novel agents. Methods102 newly diagnosed MM patients received the PAD-Mel100-LP-L regimen (Palumbo A, Abs 159, ASH 2008): as induction, four 21-day PAD cycles (Bortezomib, Pegylated-lyposomal-doxorubicin, Dexamethasone); as transplantation, tandem Mel100 (Melphalan 100 mg/m2) followed by stem cell support; as consolidation four 28-day LP cycles (Lenalidomide plus Prednisone) followed by Lenalidomide alone as maintenance. Samples from 47 newly diagnosed patients enrolled in this study have been analyzed. On CD138+ and CD138- cells separated from bone marrow (BM) aspirate, HGF and Met mRNA levels have been evaluated using a quantitative Real-Time PCR (qRT-PCR) on Abi Prism 7900 (Applied Biosystems). The JUM2 cell line was used as a calibrator for relative quantification of mRNA using the σσCt approach and Gus has been used as housekeeping gene. The cut-off value of Met mRNA expression/percentage calibrator was selected according to Receiver Operating Characteristic (ROC) analysis. ResultsmRNA expression of Met was higher in CD138+ cells than in CD138- cells (median 103, range 2 – 586 vs median 31, range 0-243 respectively; p=0.002). Met mRNA expression was significantly higher in CD138+ cells of patients with suboptimal response (partial response PR, stable disease SD, progression disease PD), compared with patients achieving complete response (CR) or very good partial remission (VGPR) (median 140 range 27-586 vs median 36.5 range 1-163 respectively; p=0.0001) (FIG 1A). With a median follow-up of 18 months, the 2-year PFS was 54% in patients with high Met mRNA expression and 87% in patients with low Met mRNA expression (p=0.007, FIG 1B); 2-year OS was 72% in patients with high Met mRNA expression and 95% in patients with low Met mRNA expression (p=0.047, FIG 1C). Patients with high levels of Met mRNA displayed albumin and beta-2-microglobuline levels similar to that observed in patients with low levels of Met mRNA. The BM plasma cells infiltration was also comparable (median 61% vs 65%) within the two groups. A similar percentage of patients in both groups showed the following cytogenetic abnormalities: t(4;14), t(14;16), del17 and del13. Interestingly, the percentage of patients carrying t(11;14) was higher in the group of patients with low Met mRNA levels in comparison with patients with high Met mRNA levels (28% vs 6%). mRNA expression of HGF was similar in responders and non responders patients and did not predict PFS and OS. Conclusion1) mRNA level of Met on CD 138+ cells is a biological marker predictive of response; 2) high level of Met mRNA at diagnosis delineates significantly inferior progression-free and overall survival in MM patients treated with both bortezomib and lenalidomide based regimens. [Display omitted] DisclosuresPatriarca:Celgene: Honoraria. Caravita:Celgene: Consultancy. Ladetto:Celgene: Research Funding; Janssen-Cilag: Research Funding. Boccadoro:Celgene: Consultancy, advisory Committees, Research Funding; Janssen-Cilag: Consultancy, advisory Committees, Research Funding; Pharmion: Consultancy, advisory Committees, Research Funding. Palumbo:Celgene: Honoraria; Janssen-Cilag: Honoraria.

The HGF/c-Met Signaling Pathway in Hodgkin Lymphoma.

Abstract 1551Poster Board I-574 IntroductionHodgkin lymphoma (HL) is a B-cell neoplasm characterized by a minority of neoplastic cells, the so-called Hodgkin and Reed-Sternberg (HRS) cells, which are located within an extensive infiltrate of reactive cells. Aberrant signaling of various receptor tyrosine kinases (RTKs) via autocrine or paracrine mechanisms contributes to the survival and proliferation of HRS cells. Activation of the hepatocyte growth factor (HGF)/c-Met signaling pathway has been implicated in the pathophysiology of many cancers, but its role in HL is poorly investigated. In this study, we investigated the expression of c-Met and HGF in HL patient tissues and studied the cell physiological effects of the HGF/c-Met signaling pathway using a c-Met tyrosine kinase inhibitor SU11274 in HL cell lines. MethodsThe expression of c-Met and HGF in HL patient tissues was studied by immunohistochemistry on a HL tissue microarray. The c-Met expression level was determined by Western blotting, while HGF mRNA and protein levels were measured by quantitative (q)RT-PCR and ELISA in four HL cell lines, i.e. L428, KMH2, L1236 and U-HO1. The effects of SU11274 treatment on the activity of the HGF/c-Met signaling pathway was determined by detection of phosphorylated downstream targets by Western blotting. Effects on cell growth and cell cycle were determined by 3-(4,5- Dimethylthiazol -2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay and by flow cytometry with Propidium iodide (PI), respectively. ResultsC-Met was detected in HRS cells in 55% (26/47) of HL patient tissues. Expression of HGF was detected in HRS cells in 5 c-Met positive and 2 c-Met negative HL patient tissues. C-Met was highly expressed in L428 compared to three other HL cell lines, whereas HGF was highly expressed in KMH2 and not or only weakly in the other three HL cell lines. Detectable levels of phosphorylated c-Met (p-Met) were observed only in L428 consistent with the high basal expression level of c-Met. Phosphorylation of c-Met, Akt and Erk1/2 were upregulated upon HGF stimulation of L428 cells. This activation could be blocked by inhibiting c-Met activation with SU11274. In functional studies, SU11274 suppressed cell growth in L428, promoted G2/M cell cycle arrest after 24h incubation, and induced tetraploidy after 48h. Washing of the cells after induction of G2/M arrest resulted in normal cell cycle progression indicating that the G2/M cell cycle arrest was reversible. Inhibition of PI3K, MEK1/2 and Erk1/2, three downstream targets of the HGF/c-Met signaling pathway, also induced G2/M cell cycle arrest in L428, indicating that these factors are involved in the G2/M cell cycle arrest induced by SU11274. ConclusionCo-expression of c-Met and HGF in HRS cells was observed in 11% of the HL patient tissues and HGF/c-Met signaling pathway regulates cell growth and cell cycle progression in L428 cells. DisclosuresNo relevant conflicts of interest to declare.

Hepatocyte growth factor gene expression after massive small bowel resection: lack of stimulation in lung and liver.

Both hepatic and renal regeneration are associated with rapid increases in hepatocyte growth factor (HGF)mRNA levels, not only in the regenerating tissue, but also in the lung. In this study, changes in the levels of HGF mRNA in the terminal ileum and also in distal organs in the rat following massive small bowel resection (MSBR) have been investigated with a sensitive S1 nuclease assay. HGF mRNA levels are low in the ileum and increase only transiently post-MSBR. In contrast to the other models of regeneration, no increase in HGF mRNA levels is observed in the lung nor in kidney and liver post-MSBR. This suggests that the ileum does not release "injurin", the putative humoral mediator of the response of the lung observed after hepatectomy or nephrectomy.

Tea Polyphenols Decrease Serum Levels of Prostate-Specific Antigen, Hepatocyte Growth Factor, and Vascular Endothelial Growth Factor in Prostate Cancer Patients and Inhibit Production of Hepatocyte Growth Factor and Vascular Endothelial Growth Factor In vitro

The purpose of this study was to determine the effects of short-term supplementation with the active compounds in green tea on serum biomarkers in patients with prostate cancer. Twenty-six men with positive prostate biopsies and scheduled for radical prostatectomy were given daily doses of Polyphenon E, which contained 800 mg of (-)-epigallocatechin-3-gallate (EGCG) and lesser amounts of (-)-epicatechin, (-)-epigallocatechin, and (-)-epicatechin-3-gallate (a total of 1.3 g of tea polyphenols), until time of radical prostatectomy. Serum was collected before initiation of the drug study and on the day of prostatectomy. Serum biomarkers hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), insulin-like growth factor (IGF)-I, IGF binding protein-3 (IGFBP-3), and prostate-specific antigen (PSA) were analyzed by ELISA. Toxicity was monitored primarily through liver function enzymes. Changes in serum components were analyzed statistically using the Wilcoxon signed rank test. Cancer-associated fibroblasts were treated with EGCG, and HGF and VEGF protein and mRNA levels were measured. HGF, VEGF, PSA, IGF-I, IGFBP-3, and the IGF-I/IGFBP-3 ratio decreased significantly during the study. All of the liver function tests also decreased, five of them significantly: total protein, albumin, aspartate aminotransferase, alkaline phosphatase, and amylase. The decrease in HGF and VEGF was confirmed in prostate cancer-associated fibroblasts in vitro. Our results show a significant reduction in serum levels of PSA, HGF, and VEGF in men with prostate cancer after brief treatment with EGCG (Polyphenon E), with no elevation of liver enzymes. These findings support a potential role for Polyphenon E in the treatment or prevention of prostate cancer.

Differences in the temporal expression of regulatory growth factors during choroidal neovascular development

Although the roles of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and hepatocyte growth factor (HGF) in pathologic neovascularization have been well characterized in certain tissues, their particular functions and expression patterns in choroidal neovascularization (CNV) have not been clearly established. After localized laser trauma to Bruch's membrane to induce CNV development, the temporal changes in mRNA and protein expression of these 3 cytokines were documented and compared histologically to areas of immunofluorescence, the proliferation of endothelial cells, neovascular development, and temporal changes in vascular permeability. Changes in mRNA and protein levels of bFGF and HGF occurred quickly and reached peak expression within hours. This activity corresponded in time to intense and localized immunofluorescence for these cytokines within the choriocapillaris within laser lesion sites. During this same initial time period, mRNA upregulation of VEGF occurred, primarily within the neural retina and this expression corresponded to intense immunolabeling of Müller cells immediately adjacent to the lesion sites. By 3 days after lasering, increased VEGF 164 protein expression was measurable, whereas early neovascular development histologically corresponded to HGF and bFGF mRNA expansion into the developing choroidal neovascular membrane (CNVM). At 7 days, CNV expansion, maturation, and increased vascular permeability corresponded to peak VEGF mRNA and protein expression and to immunofluorescence of the CNVM. Differences also occurred in the expression of precursor and activated isoforms of these cytokines in the retinal pigment epithelium/choroid as compared to those in the retina. These molecular and immunocytochemical results suggest that bFGF and HGF may be important as initial regulators neovascularization in this CNV model; whereas VEGF may be important during later phases of angiogenesis and neovascular hyperpermeability.

Hepatocyte Growth Factor and Sonic Hedgehog Expression in Cerebellar Neural Progenitor Cells Costimulate Medulloblastoma Initiation and Growth

Medulloblastomas are malignant brain tumors that arise by transformation of neural progenitor cells in the cerebellum in children. Treatment-related neurotoxicity has created a critical need to identify signaling molecules that can be targeted therapeutically to maximize tumor growth suppression and minimize collateral neurologic injury. In genetically engineered mice, activation of Sonic Hedgehog (Shh) signaling in neural stem cells in the developing cerebellum induces medulloblastomas. Hepatocyte growth factor (HGF) and its cell surface receptor c-Met are highly expressed in human medulloblastomas, and elevated levels of c-Met and HGF mRNA predict an unfavorable prognosis for patients. HGF is neuroprotective for cerebellar granule cells and promotes growth of human medulloblastoma cells in culture and in murine xenografts. We modeled the ability of HGF to induce medulloblastomas in mice using a version of the RCAS/tv-a system that allows gene transfer to cerebellar neural progenitors during their postnatal expansion phase when these cells are highly susceptible to transformation. Here, we report a high frequency of medulloblastoma formation in mice after postnatal expression of HGF in cooperation with Shh. Some tumors showed neurocytic differentiation similar to that in human nodular medulloblastomas with activated Shh signaling. Systemic administration of a monoclonal antibody against HGF prolonged survival of mice bearing Shh + HGF-induced medulloblastomas by stimulating apoptosis. These findings indicate a role for HGF in medulloblastoma initiation and growth and show efficacy of HGF-targeted therapy in a mouse model of endogenously arising tumors.

Effect of hepatocyte growth factor on methionine adenosyltransferase genes and growth is cell density‐dependent in HepG2 cells

Hepatocyte growth factor (HGF) is a potent hepatocyte mitogen but its effect in liver cancer is conflicting. Methionine adenosyltransferase (MAT) is an essential enzyme encoded by two genes (MAT1A and MAT2A), while a third gene (MAT2beta) encodes for a subunit that regulates the MAT2A-encoded isoenzyme. MAT1A is silenced while MAT2A and MAT2beta are induced in hepatocellular carcinoma (HCC). The current work examined expression of HGF/c-met in HCC and whether HGF regulates MAT genes and growth in HepG2 cells. We found the mRNA levels of HGF and c-met are markedly increased in HCC. To study the influence of cell density, HepG2 cells were plated under high-density (HD) or low-density (LD) and treated with HGF (10 ng/ml). Cell density had a dramatic effect on MAT1A expression, being nearly undetectable at LD to a ninefold induction under HD. Cell density also determined the effect of HGF. At HD, HGF increased the mRNA levels of p21 and p27, while lowering the levels of MAT genes, cyclin A, and c-met. At LD, HGF increased the mRNA levels of cyclin A, MAT2A, MAT2beta, and c-met. Consistently, HGF inhibits growth under HD but stimulates growth under LD. HGF induced sustained high ERK activation under HD as compared to LD. In summary, HGF induces genes favoring growth and is mitogenic when HepG2 cells are plated under LD; however, the opposite occurs under HD. This involves cell density-dependent differences in HGF-induced ERK activation. This may explain why HGF is mitogenic only when there is loss of cell-cell contact in vivo.

Antinecrotic and antiapoptotic effects of hepatocyte growth factor on cholestatic hepatitis in a mouse model of bile-obstructive diseases

Cholestasis, an impairment of bile outflux, frequently occurs in liver diseases. In this process, an overaccumulation of bile acids causes hepatocyte necrosis and apoptosis, leading to advanced hepatitis. Hepatocyte growth factor (HGF) is mitogenic toward hepatocytes, but it is still unclear whether HGF has physiological and therapeutic functions during the progression of cholestasis. Using anti-HGF IgG or recombinant HGF in mice that had undergone bile duct ligation (BDL), we investigated the involvement of HGF in cholestasis-induced hepatitis. After the BDL surgery, HGF and c-Met mRNA levels transiently increased in livers during the progression of cholestatic hepatitis. When c-Met tyrosine phosphorylation was blocked in the livers of BDL-treated mice by anti-HGF IgG, hepatic dysfunction became evident, associated with the acceleration of hepatocyte necrosis and apoptosis. Inversely, administration of recombinant HGF into the mice led to the prevention of cholestasis-induced inflammation: HGF suppressed the hepatic expression of intracellular adhesion molecule-1 and neutrophil infiltration in BDL-treated mice. As a result, parenchymal necrosis was suppressed in the HGF-injected BDL mice. In addition, HGF supplement therapy reduced the number of apoptotic hepatocytes in cholestatic mice, associated with the early induction of Bcl-xL. The administration of HGF enhanced hepatic repair, via accelerating G1/S progression in hepatocytes. Our study showed that 1) upregulation of HGF production is required for protective mechanisms against cholestatic hepatitis and 2) enhancement of the intrinsic defense system by adding HGF may be a reasonable strategy to attenuate hepatic inflammation, necrosis, and apoptosis under bile-congestive conditions.

Effects of Shenshuning Recipe on expression of hepatocyte growth factor in rats with glomerulosclerosis

To investigate the effects of Shenshuning Recipe (SSNR) on gene expression of hepatocyte growth factor (HGF) in renal tissues in rats with glomerulosclerosis. Glomerulosclerosis was induced in 42 rats by unilateral nephrectomy and intravenous injection of doxorubicin. Then these 42 rats were randomly divided into three groups: untreated group, SSNR-treated group and benazepril-treated group. Another eight rats were included into sham-operation group. The rats in the SSNR-treated group and the benazepril-treated group were fed SSNR or benazepril respectively for 8 weeks. The levels of 24 h urine protein (Upr), serum creatinine (Cr) and blood urea nitrogen (BUN) of rats in each group were examined. The renal morphological changes were observed under microscope, and the diameter of glomerular capillary, mesangial matrix and glomerulosclerosis index were analyzed by image analysis software. Reverse transcription-polymerase chain reaction (RT-PCR) method was used to detect the gene expression of HGF in the renal tissues. The levels of 24 h Upr, serum Cr and BUN in the untreated group were remarkably increased than those in the sham-operation group (P<0.01). The pathological morphological changes in the untreated group showed that the glomerulosclerosis was diffused around the renal tissue and the capillaries were shrunk. The expression level of mesangial matrix was up-regulated and the glomerulosclerosis index was 3.32+/-0.35. The expression level of HGF mRNA in the untreated group was obviously lower than that in the sham-operation group (P<0.05). The levels of 24 h Upr, serum Cr and BUN in the SSNR-treated group and the benazepril-treated group were remarkably decreased as compared with those in the untreated group, while the expression levels of HGF mRNA were both obviously higher than that in the untreated group (P<0.01). The pathological morphological changes in the SSNR-treated group and the benazepril-treated group were both alleviated. There was no significant difference in therapeutic effect between the SSNR-treated group and the benazepril-treated group. Shenshuning Recipe can up-regulate the expression of HGF mRNA, decrease the mesangial matrix, and improve the renal function, so that it may retard the development of glomerulosclerosis.

Expression of osteopontin and HGF/Met in adult soft tissue tumors

There is a need for molecular markers that predict biological behavior of adult soft tissue tumors. Elevated levels of osteopontin (OPN) a transformation-linked protein, have been associated with poor survival in many cancers. OPN induces cell migration in cancer cells, in part through activation of the hepatocyte growth factor (HGF) receptor (Met) and its signaling pathway. Met expression has been associated with a poor prognosis in some sarcomas. In a series of 15 patients with adult soft tissue tumors, we found that mRNA levels of OPN (p=0.015), Met (p=0.03) and HGF (p

Amelioration of Pulmonary Emphysema by In Vivo Gene Transfection With Hepatocyte Growth Factor in Rats

Hepatocyte growth factor (HGF) is an important mitogen and morphogen that contributes to the repair process after lung injury. The goal of the present study was to characterize its role in pulmonary emphysema, which may lead to the development of new treatment strategies with HGF. HGF mRNA and protein levels in lung tissue and plasma from elastase-induced emphysema rats transiently increased, then declined significantly to below the basal level in a time-dependent manner (P<0.01). Furthermore, changes in HGF were correlated with histologically progressive emphysematous changes and deterioration in pulmonary physiology. Use of the HVJ (hemagglutinating virus of Japan) envelope method resulted in successful transfection of cDNA encoding human HGF, as demonstrated by an efficient expression of HGF in alveolar endothelial and epithelial cells. Transfection of HGF resulted in a more extensive pulmonary vasculature and inhibition of alveolar wall cell apoptosis, and those effects led to improved exercise tolerance and gas exchange (P<0.05), which persisted for more than 1 month. Decreased HGF expression due to a failure in sustained endogenous production after injury was associated with emphysema-related histopathologic and physiological changes in the present rat model. In addition, induction of HGF expression by a gene-transfection method resulted in improved pulmonary function via inhibition of alveolar cell apoptosis, enhancement of alveolar regeneration, and promotion of angiogenesis.

MET and HGF predict outcome in colorectal cancer

Abstract Introduction: MET, a receptor tyrosine kinase, and its ligand, hepatocyte growth factor (HGF), are critical in cellular proliferation, motility, and invasion. We hypothesize that elevated MET and HGF gene expression predicts metastatic spread and poor survival in colorectal (CR) cancer patients. Methods: In 60 primary CR adenocarcinomas, MET and HGF mRNA was quantified with Real-Time RT-PCR. Using random primed cDNA and gene-specific PCR, specimen threshold cycle was measured and standard curves generated. Tumor mRNA levels were extrapolated, normalized to 18S RNA and compared to pooled matched normal mucosa. Median follow-up for survival analysis was 6 years. Results: When compared with normal tissue, a > 2 fold elevation in MET mRNA was seen in 69% of tumors with 48% having > 10 fold increases. Elevated HGF mRNA was noted in 47% of tumors with 19% having a > 10 fold increase. MET and HGF mRNA levels were correlated (p = 0.01). 33 patients had low expression of both genes (LOW MET/HGF) while 27 patients had high expression of both (HIGH MET/HGF). HIGH MET/HGF was associated with nodal and distant metastases (Table). Further, HIGH MET/HGF gene expression predicted poor survival (RR = 2.3, p Factor High MET/HGF n (%) Low MET/HGF n (%) p Value Relative Risk All patients 27 (100) 33 (100) — — Grade 1 1 (4) 1 (3) 0.57 — 2 23 (85) 24 (72) 3 3 (11) 8 (24) T stage 1 1 (4) 1 (3) 0.96 — 2 5 (19) 8 (24) 3 18 (67) 21 (64) 4 3 (11) 3 (9) N stage 0 9 (33) 21 (64) 0.02 1.9 1/2 18 (67) 12 (36) M stage 0 15 (56) 26 (79) 0.05 2.1 1 12 (44) 7 (21) AJCC stage 1/2 5 (19) 18 (55) 0.004 1.8 3/4 22 (81) 15 (45) Conclusions: Over-expression of MET and HGF identifies a metastatic phenotype. These molecular markers may be exploited for identifying tumors with aggressive biology and are potential therapeutic targets.

MRNA expression of fibroblast growth factors and hepatocyte growth factor in rat plantaris muscle following denervation and compensatory overload.

We addressed the question of whether hypertrophy induced by compensatory overload differs according to innervation status, and how fibroblast growth factors (FGF) and hepatocyte growth factor (HGF) mRNAs are expressed in the rat plantaris muscle during overload (OL) and/or denervation. Male Wistar rats were divided into four groups (Normal-Cont, Normal-OL, Denervated-Cont, and Denervated-OL). according to the plantaris denervation and/or overload. Three weeks later, plantaris weight in Denervated-Cont and Denervated-OL was significantly lower than in the Normal-Cont. The muscle weights in the Normal-OL were higher than in the Normal-Cont. The muscle weights in the Denervated-OL were higher than in the Denervated-Cont. Three days after the treatment, FGF-2, FGF-6, FGF-7 and HGF mRNAs in the Normal-OL were significantly higher than those in the Normal-Cont. FGF-2, FGF-6, FGF-7 and HGF mRNAs in the Denervated-OL were also significantly higher after 3 days than those in the Denervated-Cont. After 7 days, FGF-2, FGF-5, FGF-6, FGF-7 and HGF mRNAs were significantly higher in the Normal-OL than those in the Normal-Cont. At 21 days, FGF-1, FGF-6 and HGF mRNA levels were significantly increased. In the Denervated-OL, FGF-2, FGF-7 and HGF mRNAs at 7 days, and FGF-2 mRNA at 21 days were significantly higher than those in the Denervated-Cont. FGF-2 and FGF-6 mRNA levels decreased significantly following denervation; however, FGF-1, FGF-5, FGF-7 and HGF mRNA levels increased and maintained this increase for the 21-days treatment period. Muscle hypertrophy was thus induced by compensatory overload irrespective of innervation status, possibly in association with certain FGFs and HGF. The differential mRNA expression patterns of FGFs and HGF observed following compensatory overload and/or denervation suggest distinct roles for individual FGFs and HGF in muscle hypertrophy and/or atrophy.

Cisplatin up-regulates the in vivo biosynthesis and degradation of renal polyamines and c-Myc expression.

Time-dependent changes in polyamine metabolism and c-Myc expression are reported in kidney of mice treated with cisplatin, a widely used anticancer drug. We show that cisplatin significantly induces the expression of two enzymes critical to proper homeostasis of cellular polyamines, ornithine decarboxylase (ODC) and spermidine/spermine N1-acetyltransferase (SSAT). We also document the cross-talk between signalling pathway(s) induced by cisplatin injury to renal tubules and the testosterone/androgen receptor pathway. Their interaction results in a decrease in testosterone-induced ODC activity and ODC mRNA level, and in differential modulation of SSAT expression. Moreover, cisplatin and antifolate CB 3717, another nephrotoxic drug examined, severalfold up-regulate expression of c-Myc mRNA, albeit with different kinetics. However, cisplatin, contrary to CB 3717, does not induce renal hepatocyte growth factor (HGF)/c-Met expression being without effect on HGF mRNA level and significantly down-regulating c-Met transmembrane receptor message. In conclusion, these in vivo studies document significant cisplatin-induced modulation of polyamine biosynthesis/degradation and up-regulation of c-Myc expression, and suggest that c-Myc transcription factor is involved in the induction of ODC in kidney injured with antifolate, but not with cisplatin.

Time course of changes in growth factor mRNA levels in muscle of steroid-implanted and nonimplanted steers.

We used a muscle biopsy technique in conjunction with real-time PCR analysis to examine the time course of changes in muscle IGF-I, IGFBP-3, myostatin, and hepatocyte growth factor (HGF) mRNA in the longissimus muscles of Revalor-S-implanted and nonimplanted steers on d 0, 7, 12, and 26 after implantation (nine steers/treatment group). Administration of a Revalor-S implant increased (P < 0.01) ADG and improved (P < 0.05) feed efficiency, 36 and 34%, respectively, compared with steers that received no implant during the 26-d trial. Daily dry matter intake did not differ (P > 0.15) between nonimplanted and implanted steers. Steers receiving the Revalor-S implant had increased (P < 0.001) circulating IGF-I concentrations compared with nonimplanted steers. The longissimus muscles of steers receiving the Revalor-S implant contained increased (P < 0.001) IGF-I mRNA levels compared with longissimus muscles of nonimplanted steers over the 26-d duration of the study. Longissimus muscle IGF-I mRNA levels in implanted steers were increased (P < 0.003) relative to d-0 concentrations on d 7 and 12 (101% and 128%, respectively), and byd 26, longissimus muscle mRNA levels were more than three times (P < 0.0001) those in the longissimus muscles of the same steers on d 0. There was no treatment effect on the level of IGFBP-3, myostatin, or HGF mRNA in the longissimus muscle at any time point; however, levels of IGFBP-3, myostatin, and HGF mRNA increased with time on feed. Based on current and previous studies, we hypothesize that the increased IGF-I level in muscle of implanted steers by d 7 of implantation stimulates satellite cell proliferation and maintains a high number of proliferating satellite cells at a point in the growth curve where satellite cell numbers and activity are normally dropping off. This would prolong the period of rapid muscle growth, resulting in the observed increased rate and efficiency of muscle deposition in implanted steers.

Involvement of hepatocyte growth factor in branching morphogenesis of murine salivary gland.

We investigated the involvement of hepatocyte growth factor (HGF) in salivary gland (SG) branching morphogenesis. The mouse submandibular gland (SMG) starts to develop at embryonic day 11.5-12 (E11.5-E12), and branching morphogenesis occurs in the area between the mandibular bone and tongue between E14 and E16.5. Real-time reverse transcriptase-polymerase chain reaction showed that the expression of the c-met/HGF receptor gene in SMG increased and peaked between E14 and E16.5, concomitant with epithelial branching, and high levels of HGF mRNA were detected in the surrounding mesenchyme at E14-E15.5. Although strong expression of the HGF and c-met transcripts was observed in the tongue muscles, this expression was limited at E13.5-E14.5. Serum-free organ cultures were established, in which SG rudiments that contained SMG and sublingual gland (SLG) primordia (explant 1) and SMG/SLG rudiments with peripheral tissue that included part of the tongue muscle (explant 2) were isolated from E13.5 or E14 embryos. Mesenchyme-free SMG epithelium was obtained by the removal of mesenchymal tissue from explant 1. In the explant 1 and 2 organ cultures, SMG/SLG rudiments showed growth and branching morphogenesis, while mesenchyme-free epithelium failed to grow. When E13.5 or E14 mesenchyme-free epithelium and a recombinant human HGF (rh-HGF) -soaked bead were placed on Matrigel, the epithelium migrated toward the bead and formed branches, while the E13 epithelium failed to branch. The exogenous application of rh-HGF and anti-HGF antibody to the SMG/SLG rudiment cultures resulted in stimulation and inhibition, respectively, of branching morphogenesis. However, the response of E13.5 SMG to rh-HGF was very weak, while the branching of E14 SMG was enhanced strongly by rh-HGF. The branching morphogenesis of SMG was also inhibited by the addition of either antisense HGF or c-met oligodeoxynucleotides to the cultures. The development of SMG in explant 2, which was significantly better than in explant 1, was comparable to that seen in vivo. Moreover, the expression of both HGF and c-Met in the SMG of explant 2 was higher than in the SMG of explant 1. These findings provide the first demonstration that the branching morphogenesis of SMG is regulated by interactions with the surrounding mesenchyme-derived HGF and c-met expression in SMG, which occur concomitant with epithelial branching. The present data also suggest that the HGF that is released transiently from tongue muscles may contribute to the rapid development of SMG at the branching stage.