Hepatocyte growth factor protects retinal ganglion cells by increasing neuronal survival and axonal regeneration in vitro and in vivo

Background Paracrine stimulation of endogenous repair, rather than direct tissue regeneration, is increasingly accepted as a major mode of therapeutic stem and progenitor cell action; yet, this principle has not been fully established in vivo . Adipose-derived stem cells (ASCs) secrete many factors and promote reperfusion and tissue repair in ischemia models. RNA interference was used to silence the expression of the abundant protein, hepatocyte growth factor (HGF), to determine its contribution to ASC potency in vivo . Methods and Results Dual-cassette lentiviral vectors, expressing GFP and either a small hairpin RNA (shRNA) specific for HGF mRNA (shHGF) or a control sequence (shCtrl), were used to stably transduce ASCs (ASC-shHGF or ASC-shCtrl). ASC-shHGF secreted 5-fold less HGF, which resulted in a reduced ability of these cells to promote survival, proliferation and migration of mature and progenitor endothelial cells in vitro ( p <0.01). HGF knockdown also severely impaired the ability of ASCs to promote reperfusion in a mouse hindlimb ischemia model. Perfusion of the ischemic leg at 15 d in mice treated with ASC-Ctrl was 84±4%, compared to only 69±5% for ASC-shHGF ( p <0.05). Even so, ASC-shHGF retained residual activity as indicated by greater reperfusion ( p <0.05) than with saline treatment (58±6%). Capillary densities in ischemic tissues from each group followed a similar rank order (ASC-Ctrl>ASC-shHGF>saline) ( p <0.05 between each group). While there was no difference in total GFP + cells in ischemic limbs at 5 d after infusion, indicating similar homing potentials, 3-fold fewer ASC-shHGF were present in ischemic tissues at 15 d compared to ASC-shCtrl ( p <0.01). This was accompanied by an increase in TUNEL-positive ASC-shHGF cells (61 ± 0.1%) compared to ASC-Ctrl (41% ± 3.2%) in ischemic tissues at 5 d ( p <0.01); suggesting that attenuated potency of ASC-shHGF was related to reduced survival in ischemic tissues. Conclusions These results indicate that secretion of HGF is critically important for ASC potency. In addition to promoting endogenous repair, the data suggest that an important effect of HGF is autocrine promotion of ASC survival in ischemic tissue. Enhanced donor cell survival is an important goal for increasing the efficacy of cell therapy.

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Glucocorticoid effects on axonal regeneration of retinal ganglion cells in vitro

Restorative Neurology and Neuroscience ◽

10.3233/rnn-1994-6201 ◽

1994 ◽

Vol 6 (2) ◽

pp. 83-87

Author(s):

Barbara Szymankiewicz-Rak ◽

Jörg Mey ◽

Solon Thanos

Keyword(s):

Retinal Ganglion Cells ◽

Axonal Regeneration ◽

Ganglion Cells ◽

Retinal Ganglion

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First-in-human phase I trial of anti-hepatocyte growth factor antibody (YYB101) in refractory solid tumor patients

Therapeutic Advances in Medical Oncology ◽

10.1177/1758835920926796 ◽

2020 ◽

Vol 12 ◽

pp. 175883592092679

Author(s):

Seung Tae Kim ◽

Jung Yong Hong ◽

Se Hoon Park ◽

Joon Oh Park ◽

Young Whan Park ◽

...

Keyword(s):

Growth Factor ◽

Hepatocyte Growth Factor ◽

Phase I ◽

Cancer Patients ◽

Phase I Trial ◽

Maximum Tolerated Dose ◽

Safety And Efficacy ◽

Hepatocyte Growth

Background: YYB101, a humanized monoclonal antibody against hepatocyte growth factor (HGF), has shown safety and efficacy in vitro and in vivo. This is a first-in-human trial of this antibody. Materials and Methods: YYB101 was administered intravenously to refractory cancer patients once every 4 weeks for 1 month, and then once every 2 weeks until disease progression or intolerable toxicity, at doses of 0.3, 1, 3, 5, 10, 20, 30 mg/kg, according to a 3+3 dose escalation design. Maximum tolerated dose, safety, pharmacokinetics, and pharmacodynamics were studied. HGF, MET, PD-L1, and ERK expression was evaluated for 9 of 17 patients of the expansion cohort (20 mg/kg). Results: In 39 patients enrolled, no dose-limiting toxicity was observed at 0.3 mg/kg, and the most commonly detected toxicity was generalized edema ( n = 7, 18.9%) followed by pruritis and nausea ( n = 5, 13.5%, each), fatigue, anemia, and decreased appetite ( n = 4, 10.8%, each). No patient discontinued treatment because of adverse events. YYB101 showed dose-proportional pharmacokinetics up to 30 mg/kg. Partial response in 1 (2.5%) and stable disease in 17 (43.5%) were observed. HGF, MET, PD-L1, and ERK proteins were not significant predictors for treatment response. However, serum HGF level was significantly lowered in responders upon drug administration. RNA sequencing revealed a mesenchymal signature in two long-term responders. Conclusion: YYB101 showed favorable safety and efficacy in patients with refractory solid tumors. Based on this phase I trial, a phase II study on the YYB101 + irinotecan combination in refractory metastatic colorectal cancer patients is planned. Conclusion: ClinicalTrials.gov Identifier: NCT02499224

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Protamine enhances the proliferative activity of hepatocyte growth factor in rats

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.1998.274.1.g21 ◽

1998 ◽

Vol 274 (1) ◽

pp. G21-G28 ◽

Cited By ~ 1

Author(s):

Ke-Xin Liu ◽

Yukio Kato ◽

Tai-Ichi Kaku ◽

Kunio Matsumoto ◽

Toshikazu Nakamura ◽

...

Keyword(s):

Growth Factor ◽

Hepatocyte Growth Factor ◽

Proliferative Activity ◽

Plasma Clearance ◽

Mitogenic Response ◽

Enhancing Effect ◽

A Cell ◽

Hepatocyte Growth

The effect of protamine on the proliferative activity of hepatocyte growth factor (HGF) was examined in α-naphthyl isothiocyanate-intoxicated rats. Protamine preinjection increased the hepatocyte labeling index induced by HGF four- to fivefold. A similar effect was also observed in partially hepatectomized rats. Because a cell surface heparin-like substance can bind to HGF and protamine has an affinity for heparin, protamine may affect HGF pharmacokinetics. In fact, protamine injection caused a transient increase in plasma HGF concentrations after administration of HGF and, in vitro, protamine eluted HGF prebound to heparin-Sepharose. Protamine also reduced the plasma clearance of HGF and increased 2.5-fold the exposure of hepatocytes to HGF in vivo. The enhancing effect of protamine on the mitogenic response of hepatocytes to HGF was also observed in vitro (∼2-fold after protamine pretreatment compared with HGF alone), suggesting that the enhancing effect of protamine on HGF-induced liver regeneration results from dual effects exerted by protamine 1) lowering the overall elimination of HGF and 2) directly stimulating hepatocyte mitosis induced by HGF.

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