Yosuke Aihara

Nara Medical University, Nara-shi, Nara, Japan

Are you Yosuke Aihara?

Claim your profile

Publications (21)41.81 Total impact

  • [show abstract] [hide abstract]
    ABSTRACT: Given the well-documented adverse side effects of sorafenib, many sorafenib-treated patients may need the reduced initial dose of the compound, and an alternative sorafenib-based therapy, which exerts similar clinical benefit, is anticipated. An angiostatic therapy with sorafenib is considered one of the promising approaches for chemoprevention of hepatocellular carcinoma. The aim of the current study was to elucidate the combination effect of low dose of sorafenib and angiotensin-II receptor blocker (ARB) on hepatocarcinogenesis, especially in conjunction with angiogenesis. The chemopreventive effect on the development of liver preneoplastic lesions, angiogenesis, and several indices was elucidated in rats. We also performed several sets of in vitro experiments to examine the mechanisms involved. Using a non-diabetic rat model of steatohepatitis with choline deficient L-amino acid-defined diet, sorafenib demonstrated marked inhibition of preneoplastic lesions in a dose dependent manner. Combined treatment with ARB (losartan) at a clinically comparable dose and half dose of sorafenib resulted in the inhibitory effect equivalent to that of common dose of sorafenib along with suppression of hepatic neovascularization and potent angiogenic factor, vascular endothelial growth factor. Furthermore, similar combined inhibitory outcomes were observed in several sets of in vitro studies. Since the combinatorial treatment using low doses of sorafenib and ARB could sufficiently induce inhibitory effect on the development of preneoplastic lesions at the magnitude similar to the conventional dose of sorafenib, this regimen may provide new strategy for patients intolerant of the usual dose of sorafenib in the future.
    Journal of Gastroenterology 11/2013; · 3.79 Impact Factor
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: Branched-chain amino acids (BCAAs) reportedly inhibit the incidence of hepatocellular carcinoma (HCC) in patients with liver cirrhosis and obesity that is frequently associated with insulin resistance (IR). We previously reported that BCAAs exert a chemopreventive effect against HCC under IR conditions in rats. The aim of the present study was to examine the effect of BCAAs on the cumulative recurrence of HCC under IR conditions in the clinical practice. BCAA granules (Livact®, 12 g/day) were administered for 60 months following the local curative therapy for HCC, and several indices were determined. Treatment with BCAAs markedly inhibited the cumulative recurrence of HCC in patients with a high IR index [homeostasis model assessment (HOMA)-IR >2.5], but not in patients with HOMA-IR of ≤2.5. BCAA also improved the HOMA-IR, and the inhibitory effect was observed regardless of the serum albumin (Alb) levels. Similarly, BCAA treatment revealed a marked suppressive effect in patients with high fasting insulin [immune reactive insulin (IRI) >15 U/ml], but not with IRI of ≤15. BCAA treatment did not result in differences in HCC recurrence in patients with high and low glucose levels [fasting blood sugar (FBS) >110 and ≤110, respectively]. Furthermore, serum levels of the soluble form of vascular endothelial growth factor receptor 2 (sVEGFR2) were significantly inhibited along with these clinical effects. Our findings indicate that the inhibitory effect of BCAAs was achieved, at least partly, by coordinated effects of anti-angiogenesis and IR improvement. Since BCAAs are widely and safely used in clinical practice to treat patients with chronic liver diseases, BCAAs may represent a new strategy for secondary chemoprevention for HCC patients with IR. Moreover, our findings suggest that sVEGFR2 may be a useful clinical predictive marker for BCAA treatment under IR conditions.
    Oncology Reports 05/2013; · 2.30 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: BACKGROUND: Dipeptidyl peptidase-4 inhibitor (DPP4-I) is clinically used as a new oral antidiabetic agent. Although DPP4 is reportedly associated with the progression of chronic liver diseases, the effect of DPP4-I on liver fibrosis development is still obscure. This study was designed to elucidate the effect of DPP4-I on liver fibrosis development in conjunction with the activated hepatic stellate cells (Ac-HSCs). METHODS: The antifibrotic effect of DPP4-I was assessed in vivo and in vitro using porcine serum-induced experimental liver fibrosis model. DPP4-I, sitagliptin, at a clinically comparable low dose was administered by gavage daily. RESULTS: DPP4-I significantly attenuated liver fibrosis development along with the suppression of hepatic transforming growth factor (TGF)-β1, total collagen, and tissue inhibitor of metalloproteinases-1 in a dose-dependent manner. These suppressive effects occurred almost concurrently with the attenuation of HSCs activation. Our in vitro studies showed that DPP4-I inhibited platelet-derived growth factor-BB-mediated proliferation of the Ac-HSCs as well as upregulation of TGF-β1 and α1(I)-procollagen at magnitudes similar to those of the in vivo studies. The inhibitory effects of DPP4-I against HSCs proliferation and fibrogenic gene expression are mediated through the inhibition of the phosphorylation of ERK1/2, p38 and Smad2/3, respectively. CONCLUSIONS: DPP4-I markedly inhibits liver fibrosis development in rats via suppression of HSCs proliferation and collagen synthesis. These suppressive effects are associated with dephosphorylation of ERK1/2, p38 and Smad2/3 in the HSCs. Since DPP4-I is widely used in clinical practice, this drug may represent a potential new therapeutic strategy against liver fibrosis in the near future.
    Journal of Gastroenterology 03/2013; · 3.79 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: AIM: Renin is a rate-limiting enzyme of the renin-angiotensin system (RAS), and several reports have shown that renin plays an important role in several pathological processes. Although RAS is known to play a pivotal role in the progression of non-alcoholic steatohepatitis (NASH), the role of renin is still obscure. The aim of the current study was to examine the effect of the clinically used direct renin inhibitor (DRI), aliskiren, on the progression of NASH in a rat model. METHODS: The effects of DRI on the choline-deficient L-amino acid-defined (CDAA) diet-induced rat NASH model was examined in conjunction with the activated hepatic stellate cells (Ac-HSC) and neovascularization, both of which are known to play important roles in liver fibrosis development and hepatocarcinogenesis, respectively. RESULTS: DRI exerted a marked inhibitory effect against liver fibrosis development and glutathione-S-transferase placental form (GST-P) positive preneoplastic lesions along with suppression of the Ac-HSC and neovascularization in a dose-dependent manner. DRI also inhibited the hepatic expressions of transforming growth factor-beta 1 (TGF-beta 1), angiotensin-II (AT-II) and vascular endothelial growth factor (VEGF). These results indicated that renin played a pivotal role in the liver fibrosis development and hepatocarcinogenesis of NASH. CONCLUSION: Because DRI is already widely used in the clinical practice with safety, this drug may represent a potential new strategy against the progression of NASH in the future.
    Hepatology Research 01/2013; · 2.07 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: BACKGROUD AND AIM: The innate immune system, including toll-like receptor-4 (TLR4) signaling cascade and angiotensin-II (AT-II) play important roles in the progression of liver fibrosis development, the crosstalk between TLR4 and AT-II has not been elucidated yet. The aim of the current study was to elucidate the effect of AT-II type 1 receptor (AT1-R) blocker (ARB), on the liver fibrosis development, especially in conjunction with the interaction of TLR4 and AT-II in the rat model of nonalcoholic steatohepatitis (NASH). METHODS: F344 rats were fed a choline-deficient L-amino-acid-defined (CDAA) diet for 8 weeks and the effects of losartan (LOS) were elucidated in conjunction with activated hepatic stellate cells (Ac-HSC) activation, TLR4, nuclear factor-κB (NF-κB), and transforming growth factor-β. (TGF-β) expressions. In Vitro study was carried to elucidate the effect of AT-II on several indices including TLR4, myeloid differentiation factor 88 (MyD88), NF-κB, and TGF-β expressions in the rat HSC. RESULTS: ARB markedly inhibited liver fibrosis development along with suppression of the number of Ac-HSC and TGF-β. These inhibitory effects of ARB were almost in parallel with suppression of the hepatic TLR4 and NF-κB expressions. Our in-vitro study showed that AT-II significantly augmented the TLR4 mRNA expression in a dose- and time-dependent manner via AT1-R in the Ac-HSC. AT-II also augmented the lipopolysaccharide (LPS)-induced MyD88, NF-κB, and TGF-β. and these increments were attenuated by treatment with ARB. CONCLUSIONS: These studies indicated that the crosstalk between TLR4 signaling cascade and AT-II plays a pivotal role in liver fibrosis development in NASH.
    Journal of Gastroenterology and Hepatology 01/2013; · 3.33 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: AIM: Both angiotensin-II (AT-II) and aldosterone (Ald) play pivotal roles in the pathogenesis of diseases in several organs including the liver. We previously reported that suppression of AT-II and Ald with angiotensin-converting enzyme inhibitor (ACE-I) and selective Ald blocker (SAB), respectively, attenuated the rat liver fibrogenesis and hepatocarcinogenesis. The aim of our current study was to elucidate the combined effects of ACE-I and SAB in the progression of a non-diabetic rat model of steatohepatitis, and the possible mechanisms involved. METHODS: In the choline-deficient L-amino acid-defined (CDAA) diet-induced model, the effects of ACE-I and SAB on liver fibrosis development and hepatocarcinogenesis were elucidated, especially in conjunction with neovascularization. RESULTS: Treatment with both ACE-I and SAB suppressed the development of liver fibrosis and glutathione-S-transferase placental form (GST-P) positive pre-neoplastic lesions. The combined treatment with both agents exerted more inhibitory effects as compared with either a single agent along with suppression of the activated hepatic stellate cells (Ac-HSC) and neovascularization, both of which play important roles in these processes. Our in vitro study showed that AT-II type 1 receptor blocker (ARB) and SAB inhibited Ac-HSC proliferation and in vitro angiogenesis along with suppression of the in vivo studies. CONCLUSION: Dual blockade of AT-II and Ald suppresses the progression of a non-diabetic rat model of steatohepatitis. Because both agents are widely and safely used in clinical practice, this combination therapy could be an effective new strategy against steatohepatitis in the future.
    Hepatology Research 11/2012; · 2.07 Impact Factor
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: Sorafenib, a multikinase inhibitor, is the first and only drug, which improves significantly the overall survival in patients with advanced hepatocellular carcinoma (HCC). However, many patients experience diverse side effects, some of them severe and unexpected. To date, acute acalculous cholecystitis has not been documented in association with a HCC patient treated with sorafenib. Here, we report the case of a 43-year-old woman with hepatitis C virus-related advanced HCC. She received sorafenib, and later complained of a sudden onset of severe right hypocondrial pain with rebound tenderness and muscle defense. Laboratory examination showed mild elevation of transaminases, biliary enzymes, bilirubin, inflammation markers, and a marked peripheral eosinophilia. Abdominal computed tomography (CT) revealed a swollen gallbladder with exudate associated with severe inflammation without stones or debris. Consequently, sorafenib treatment was stopped immediately, and steroid-pulse therapy was performed. Steroid therapy drastically improved all clinical manifestations along with normalization of CT findings, eosinophilia, and liver functions. In summary, we herein report a rare case of acute severe acalculous cholecystitis associated with sorafenib in the patient with advanced HCC.
    World journal of gastrointestinal oncology. 05/2012; 4(5):115-8.
  • [show abstract] [hide abstract]
    ABSTRACT: Angiogenesis plays a pivotal role in many pathological processes including chronic liver diseases. Various factors, such as renin-angiotensin-aldosterone system (RAAS), insulin resistance (IR), and reactive oxygen species (ROS) contribute reciprocally to promote angiogenesis. Blockade of RAAS by angiotensin-converting enzyme inhibitor (ACE-I) or angiotensin II (AngII) receptor blocker (ARB) markedly attenuates liver fibrosis and hepatocellular carcinoma (HCC) along with suppression of angiogenesis, IR, and ROS. Aldosterone (Ald), a downstream component of AngII, is also involved in these processes, and a selective Ald blocker (SAB) significantly suppressed the progression of chronic liver diseases. The IR status itself has shown to directly accelerate the progression of chronic liver diseases whereas inhibition of ROS by iron chelator suppressed it through augmentation and inhibition of neovascularization. The combination therapy of ACE-I/ARB/SAB with other clinically used agents, such as interferon, imatinib mesylate, vitamin K, iron chelator, and branched-chain amino acids (BCAA) exerted more potent inhibitory effects on the development of liver fibrosis and HCC than the treatment using a single agent alone. Collectively, the anti-angiogenic treatment targeting RAAS, IR, ROS with clinically available agents may become a new therapeutic strategy against the progression of chronic liver diseases.
    Current Medicinal Chemistry 02/2012; 19(12):1889-98. · 4.07 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: An effective therapeutic strategy for suppressing liver fibrosis should improve the overall prognosis of patients with chronic liver diseases. Although enormous efforts are ongoing to develop anti-fibrotic agents, no drugs have yet been approved as anti-fibrotic agents for humans. Insulin resistance (IR) is reportedly involved in the progression of liver fibrosis. The aim of the present study was to evaluate the effect of combination treatment with a clinically used branched-chain amino acid (BCAA) and an angiotensin-converting enzyme inhibitor (ACE-I) on several fibrotic indices in patients with liver cirrhosis under the condition of IR. BCAA granules (Livact; 12 g/day) and/or ACE-I (perindopril; 4 mg/day) were administered, and several indices were analyzed. A 48-month follow-up revealed that the combination treatment with BCAA and ACE-I markedly improved the progression of serum fibrosis markers, whereas single treatment with either BCAA or ACE-I did not exert these inhibitory effects. The plasma level of transforming growth factor-β was significantly attenuated almost in parallel with the suppression of serum fibrosis markers. Furthermore, the combined treatment with BCAA and ACE-I improved the serum albumin level and IR, which was evaluated using the homeostasis model assessment method for IR. Taken together, since both BCAA and ACE-I are widely used with safety in clinical practice, these results indicate that this combination therapy may represent a potential new future strategy against liver fibrosis development in patients with liver cirrhosis under the condition of IR.
    Molecular Medicine Reports 11/2011; 5(2):539-44. · 1.17 Impact Factor
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: Sarcoidosis is a chronic multi-systemic granulomatous disease, and liver involvement frequently occurs. in most cases, no evidence of liver dysfunction is observed, and portal hypertension due to sarcoid liver diseases is a rareoccurrence. Moreover, no case of liver sarcoidosis has ever been reported with confirmation of the disease progression. Herein we describe a patient having hepatic sarcoidosis with severe portal hypertension and liver dysfunction. The diagnosis was histologically confirmed from granulomatous status to established liver cirrhosis over 10 years. A 46-year-old woman developed massive hematemesis due to the rupture of gastric cardial varices. She underwent emergency endoscopic injection sclerotherapy, and clear evidence of chronic hepatic failure. Twelve years ago, she was diagnosed as having sarcoidosis with respiratory clinicalsymptoms. Liver biopsy revealed asymptomatic incidental granulomas without fibrosis development. After a couple of years, features of liver dysfunction were manifest and progressed. Ten years after the first biopsy, a second liver biopsy was performed, and well established dense fibrosis was revealed. Although significant liver dysfunction with portal hypertension is rarely seen in sarcoidosis, this case indicates that we have to consider the possibility that sarcoidosis may cause end-stage liver cirrhosis.
    World journal of hepatology. 10/2011; 3(10):271-4.
  • [show abstract] [hide abstract]
    ABSTRACT: Insulin resistance (IR) is reportedly involved in the progression of hepatocellular carcinoma (HCC). Since neovascularization plays an important role in hepatocarcinogenesis and IR, an angiostatic therapy may be considered as one of the promising approaches for chemoprevention against HCC. The aim of the current study was to examine the combination effect of a clinically used branched-chain amino acid (BCAA) and an angiotensin-converting enzyme inhibitor (ACE-I), both reportedly possess anti-angiogenic and IR-improving activities, on the cumulative recurrence after curative therapy. BCAA granules (Livact; 12 g/day) and/or ACE-I (perindopril; 4 mg/day) were administered after the curative therapy for HCC, and several indices were analyzed. A 48-month follow-up revealed that the combination treatment with BCAA and ACE-I markedly inhibited the cumulative recurrence of HCC under IR conditions, whereas neither single treatment exerted a significant inhibition. The soluble form of the vascular endothelial growth factor (VEGF; a central angiogenic factor) receptor-2 (sVEGFR2) was significantly decreased only three months after the treatment without recurrence. We also observed that IR, determined by the homeostasis model assessment (HOMA-IR), was significantly improved by this regimen, indicating that an inhibitory effect was achieved, at least partly, by coordinated effects of anti-angiogenesis and IR improvement. In conclusion, since both BCAA and ACE-I are widely used in clinical practice with safety, this combination therapy may represent a potential new strategy for chemoprevention against IR-based HCC recurrence in the future. Moreover, sVEGFR2 may become a useful clinical predictive marker of this combination treatment.
    Oncology Reports 08/2011; 26(6):1547-53. · 2.30 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Angiogenesis is a complex and critical process essential for supporting the growth of hepatocellular carcinoma (HCC) as well as hepatocarcinogenesis. Recent studies have revealed that renin-angiotensin system (RAS) is involved in many types of cancer including HCC. Some studies have proven that suppression of angiotensin-II (AT-II) by a clinically used angiotensin-converting enzyme inhibitor (ACE-I) significantly attenuated the HCC growth and hepatocarcinogenesis along with down-regulation of a potent angiogenic factor; namely, the vascular endothelial growth factor (VEGF). When used in combination with the clinical available drugs such as interferon (IFN) and vitamin K (VK), ACE-I exerted more potent anti-tumor activities as compared with either single agent in addition to suppression of the intra-tumoral angiogenesis both in experimental models and clinical practice. It is well known that AT-II plays an important role in the insulin resistance (IR), and IR is reportedly involved in the progression of HCC. The combination of ACE-I and branched-chain amino acids (BCAA) exerted a marked chemopreventive effect against HCC under the condition of IR. In addition to AT-II, aldosterone (Ald), which plays a role in the downstream of AT-II, is also involved in the HCC development, and a clinically used selective Ald blocker (SAB) significantly suppressed the HCC growth and hepatocarcinogenesis. Since ACE-I, IFN, VK, BCAA, and SAB are already in widespread clinical use without any serious adverse effects, they may represent a potential new strategy for cancer therapy and chemoprevention against HCC especially in combination with other angiostatic agents.
    Current Cancer Drug Targets 04/2011; 11(4):431-441. · 4.00 Impact Factor
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: Budd-Chiari syndrome is a very rare pathological entity that ultimately leads to liver failure. Several therapeutic modalities, including percutaneous transluminal angioplasty, have been attempted to save the life of patients with Budd-Chiari syndrome. Few reports have described a salvage living donor liver transplantation performed after percutaneous transluminal angioplasty in a patient with acute Budd-Chiari syndrome. A 26-year-old Japanese man developed severe progressive manifestations, such as massive ascites and hematemesis due to rupture of esophageal varices. After making several investigations, we diagnosed the case as Budd-Chiari syndrome. We first performed percutaneous transluminal angioplasty to dilate a short-segment stenosis of his inferior vena cava. The first percutaneous transluminal angioplasty greatly improved the clinical manifestations. However, after a year, re-stenosis was detected, and a second percutaneous transluminal angioplasty failed to open the severe stricture of his inferior vena cava. Since our patient had manifestations of acute liver failure, we decided to perform salvage living donor liver transplantation from his brother. The transplantation was successfully performed and all clinical manifestations were remarkably alleviated. In cases of recurrent Budd-Chiari syndrome, the blocked hepatic venous outflow is not always relieved, even with invasive therapies. We have to take into account the possibility of adopting alternative salvage therapies if the first therapeutic modalities fail. When invasive therapy such as percutaneous transluminal angioplasty fails, liver transplantation should be considered as an alternative option.
    Journal of Medical Case Reports 03/2011; 5:124.
  • [show abstract] [hide abstract]
    ABSTRACT: Angiotensin II type I receptor blocker and iron chelator reportedly exert suppressive effects on nonalcoholic steatohepatitis (NASH) progression, including liver fibrosis and hepatocarcinogenesis. The aim of this study was to elucidate the combined effect of losartan (LOS), an angiotensin II type I receptor blocker, and deferasirox (DSX), a newly developed oral iron chelator, on the progression of NASH in rats. To induce NASH, F344 rats were fed a choline-deficient l-amino acid-defined diet for 12 wk, and the effects of LOS and DSX at clinically comparable low doses were elucidated in conjunction with oxidative stress, neovascularization, and hepatic stellate cells (HSC) activation, all known to play important roles in the progression of NASH. Treatment with both LOS and DSX suppressed choline-deficient L-amino acid-defined diet-induced liver fibrosis development and hepatocarcinogenesis. This combination treatment exerted a stronger inhibitory effect compared with treatment with a single agent. These inhibitory effects occurred almost concurrently with the suppression of oxidative stress, neovascularization, and HSC activation. Our in vitro study demonstrated that LOS and DSX inhibited angiotensin II-induced proliferation, transforming growth factor-β(1) expression of activated HSC, and in vitro angiogenesis. These results indicated that dual inhibition by combined treatment of LOS and DSX attenuated the progression of NASH. Since both agents are widely used in clinical practice, this combination therapy may represent a potential new strategy against NASH in the near future.
    AJP Gastrointestinal and Liver Physiology 03/2011; 300(6):G1094-104. · 3.65 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: An effective therapeutic strategy for suppressing liver fibrosis development should improve the overall prognosis of patients with chronic liver diseases. Despite efforts to develop anti-fibrotic agents, no drugs have yet been approved as anti-fibrotic treatments for humans. An alternative strategy may be to employ a clinically available agent that also exhibits anti-fibrotic activities, for which the safety of long-term administration has been proven. The aim of the current study was to elucidate the combined effect of clinically used interferon (IFN), ribavirin (Rib) and angiotensin-II receptor blocker (ARB) on liver fibrosis development in mice. A model of CCl4-induced hepatic fibrosis was used to assess the effect of IFN, Rib and ARB. IFN, Rib and ARB were administered after a two-week treatment with CCl4, and the hepatic indices of fibrosis were assessed at eight weeks. Single treatment with IFN, Rib or ARB at the clinically available comparable doses significantly attenuated the liver fibrogenesis associated with the suppression of the number of α-smooth muscle actin positive cells, and the hepatic transforming growth factor-β (TGF-β) mRNA. Hepatic neovascularization, which is also known to play a pivotal role in liver fibrogenesis, and vascular endothelial growth factor (VEGF), a potent angiogenic factor, were also markedly inhibited. Combination treatment with any two agents exerted a more potent inhibitory effect than any single treatment. Moreover, the triple cocktail treatment revealed further suppressive effects than any two agent combination. Furthermore, in vitro studies showed that similar combined effects were observed on the proliferation and TGF-β mRNA expression of activated hepatic stellate cells and endothelial cell tube formation. These results indicate that the cocktail combination treatment of clinically used IFN, Rib and ARB may provide a new strategy for anti-liver fibrosis therapy.
    International Journal of Molecular Medicine 03/2011; 28(1):81-8. · 1.96 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Angiogenesis is a complex and critical process essential for supporting the growth of hepatocellular carcinoma (HCC) as well as hepatocarcinogenesis. Recent studies have revealed that renin-angiotensin system (RAS) is involved in many types of cancer including HCC. Some studies have proven that suppression of angiotensin-II (AT-II) by a clinically used angiotensin-converting enzyme inhibitor (ACE-I) significantly attenuated the HCC growth and hepatocarcinogenesis along with down-regulation of a potent angiogenic factor; namely, the vascular endothelial growth factor (VEGF). When used in combination with the clinical available drugs such as interferon (IFN) and vitamin K (VK), ACE-I exerted more potent anti-tumor activities as compared with either single agent in addition to suppression of the intra-tumoral angiogenesis both in experimental models and clinical practice. It is well known that AT-II plays an important role in the insulin resistance (IR), and IR is reportedly involved in the progression of HCC. The combination of ACE-I and branched-chain amino acids (BCAA) exerted a marked chemopreventive effect against HCC under the condition of IR. In addition to AT-II, aldosterone (Ald), which plays a role in the downstream of AT-II, is also involved in the HCC development, and a clinically used selective Ald blocker (SAB) significantly suppressed the HCC growth and hepatocarcinogenesis. Since ACE-I, IFN, VK, BCAA, and SAB are already in widespread clinical use without any serious adverse effects, they may represent a potential new strategy for cancer therapy and chemoprevention against HCC especially in combination with other angiostatic agents.
    Current cancer drug targets 03/2011; 11(4):431-41. · 5.13 Impact Factor
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: The identification of biomarkers of anti-angiogenic therapy that predict clinical benefit is of vital importance. We previously reported that a combination treatment with clinically available safe agents, specifically angiotensin-converting enzyme inhibitor (ACE-I) and vitamin K (VK), inhibited the cumulative recurrence of hepatocellular carcinoma (HCC) via suppression of the vascular endothelial growth factor (VEGF). The present study aimed to identify non-invasive biological markers that predict the clinically beneficial effect of this combination regimen. A combination of ACE-I (perindopril; 4 mg/day) and VK (menatetrenone; 45 mg/day) was administered for 54 months following curative therapy for HCC. The cumulative recurrence and several indices, which are reportedly considered as biological markers of anti-angiogenic therapies, were analyzed. The combined treatment of ACE-I and VK markedly inhibited the cumulative recurrence of HCC during the 54-month follow-up. The serum VEGF and soluble VEGF receptor (sVEGFR)-2 were significantly suppressed with this combination regimen, whereas sVEGFR-1 was not. In HCC patients without recurrence, a significant suppression of VEGF and sVEGFR-2 was achieved within 6 and 3 months after treatment, respectively. In conclusion, the combination treatment of ACE-I and VK is a potentially novel anti-angiogenic strategy for secondary chemoprevention against HCC since the two agents are widely used in clinical practice without serious side effects. Furthermore, sVEGFR-2 may become a useful clinical predictive marker of this combination treatment.
    Oncology letters 01/2011; 2(1):69-73. · 0.24 Impact Factor
  • [show abstract] [hide abstract]
    ABSTRACT: Although non-alcoholic steatohepatitis (NASH) may progress to cirrhosis and hepatocellular carcinoma (HCC), no effective therapeutic modalities have been fully established yet. Recent studies have shown that the renin-angiotensin-aldosterone-system plays an important role in NASH. The aim of our current study was to elucidate the effects of aldosterone (Ald) inhibition on the progression of NASH. In the choline-deficient L-amino acid-defined diet-induced rat NASH model, the effects of a clinically used selective Ald blocker (SAB) were elucidated in conjunction with the activated hepatic stellate cells (HSC) and neovascularization, which are both known to play important roles in liver fibrosis development and hepatocarcinogenesis, respectively. Liver fibrosis development and the glutathione-S-transferase placental form-positive pre-neoplastic lesions were both markedly attenuated by SAB along with the suppression of the activated HSC and neovascularization. SAB inhibited the hepatic expression of transforming growth factor-beta 1 and also that of the vascular endothelial growth factor. Our in vitro study showed that SAB also inhibited the Ald-induced HSC proliferation and in vitro angiogenesis in a dose-dependent manner. These results indicated that Ald plays a pivotal role in the progression of NASH. Considering that SAB is already widely used in clinical practice, this drug could represent a potential new strategy against NASH in the future.
    International Journal of Molecular Medicine 09/2010; 26(3):407-13. · 1.96 Impact Factor
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: Although administration of the vascular endothelial growth factor (VEGF), a potent angiogenic factor, could improve the overall survival of destroyed sinusoidal endothelial cells (SEC) in chemically induced murine acute hepatic failure (AHF), the mechanistic roles of the VEGF receptors have not been elucidated yet. The respective roles of VEGF receptors; namely, Flt-1 (VEGFR-1: R1) and KDR/Flk-1 (VEGFR-2: R2), in the D-galactosamine (Gal-N) and lipopolysaccharide (LPS)-induced AHF were elucidated with specific neutralizing monoclonal antibody against R1 and R2 (R1-mAb and R2-mAb, respectively). The serum ALT elevation, with a peak at 24 h after Gal-N+LPS intoxication, was markedly augmented by means of the R1-mAb and R2-mAb. The aggregative effect of R2-mAb was more potent than that of R1-mAb, and the survival rate was 70% in the R2-mAb-treated group and 100% in the other groups. The results of SEC destruction were almost parallel to those of the ALT changes. Our in-vitro study showed that R1-mAb and R2-mAb significantly worsened the Gal-N+LPS-induced cytotoxicity and apoptosis of SEC mediated by caspase-3, which were almost of similar magnitude to those in the in-vivo study. In conclusion, these results indicated that R2 is a major regulator of the salvage effect of VEGF on the maintenance of SEC architecture and the anti-apoptotic effects against chemically-induced murine AHF.
    Journal of Angiogenesis Research 01/2010; 2:16.
  • Source
    [show abstract] [hide abstract]
    ABSTRACT: Apart from simple steatosis, the non-alcoholic steatohepatitis (NASH) can progress into liver fibrosis and cirrhosis. To date, however, no widely accepted therapeutic modalities have been established against NASH in the clinical practice. To find out promising new therapeutic agents, it is important to employ an appropriate experimental model of NASH, such as association with insulin resistance. In the current study, we found that losartan, a clinically used angiotensin-II type 1 receptor blocker, significantly attenuated a choline-deficient L-amino acid-defined (CDAA) diet-induced steatohepatitis in obese diabetic- and insulin resistance-associated Otsuka Long-Evans Tokushima Fatty (OLETF) rats. The transforming growth factor-beta, a well-known major fibrogenic cytokine, was also suppressed in a similar magnitude to that of the fibrosis area. Noteworthy was the finding that these inhibitory effects were achieved even at a clinically comparable low dose. Since losartan is widely used without serious side effects in the clinical practice, this agent may be an effective new therapeutic strategy against NASH.
    BMC Research Notes 06/2009; 2:70.