Sorafenib inhibits liver regeneration in rats

Design, synthesis and biological evaluation of a new thieno[2,3-d]pyrimidine-based urea derivative with potential antitumor activity against tamoxifen sensitive and resistant breast cancer cell lines

Breast cancer (BC) and endocrine resistance to chemotherapy are challenging problems where angiogenesis plays fundamental roles. Thus, targeting of VEGFR-2 signalling pathway has been an attractive approach. In this study, we synthesised a new sorafenib analogue, thieno[2,3-d]pyrimidine based urea derivative, KM6. It showed 65% inhibition of VEGF2 tyrosine kinase activity and demonstrated a potential antitumor activity in TAM-resistant, LCC2, and its parental MCF7 BC cells. KM6 retained the sensitivity of LCC2 through upregulation of key enzymes of apoptosis and proteins of cell death including caspases 3, 8, 9, P53, BAX/BCL-2 ratio and LDH in media. It downregulated mRNA expression of Ki-67, survivin, Akt, and reduced levels of ROS and glucose uptake. Moreover, KM6 reduced the levels of inflammation markers PGE2, COX2, IL-1β and IL6 and metastasis markers MMP-2 and MMP-9. In conclusion, KM6 is a promising compound for ER + and TAM-resistant BC with many potential antitumor and polypharmacological mechanisms.

Coordinated cytochrome P450 expression in mouse liver and intestine under different dietary conditions during liver regeneration after partial hepatectomy

Liver resection is performed to remove tumors in patients with liver cancer, but the procedure's suitability depends on the regenerative ability of the liver. It is important to consider the effects of exogenous factors, such as diets, on liver regeneration for the recovery of function. The evaluation of drug metabolism during liver regeneration is also necessary because liver dysfunction is generally observed after the operation. Here, we investigated the influence of a purified diet (AIN-93G) on liver regeneration and changes in the mRNA expression of several cytochrome P450 (CYP) isoforms in the liver and small intestine using a two-thirds partial hepatectomy (PH) mouse model fed with a standard diet (MF) and a purified diet. Liver regeneration was significantly delayed in the purified diet group relative to that in the standard diet group. The liver Cyp2c55 and Cyp3a11 expression was increased at 3 day after PH especially in the purified diet group. Bile acid may partly cause the differences in liver regeneration and CYP expression between two types of diets. On the other hand, Cyp3a13 expression in the small intestine was transiently increased at day 1 after PH in both diet groups. The findings suggest that compensatory induction of the CYP expression occurred in the small intestine after attenuation of drug metabolism potential in the liver. The present results highlight the importance of the relationship between liver regeneration, drug metabolism, and exogenous factors for the effective treatment, including surgery and medication, in patients after liver resection or transplantation.

A new technique for accelerated liver regeneration: An experimental study in rats

BACKGROUND

Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) is used to accelerate growth of the future liver remnant. We investigated alternative methods for increasing the future liver remnant.

METHODS

A total of 152 rats were randomized as follows: (1) sham; (2) portal vein ligation; (3) portal vein ligation/surgical split (ALPPS); (4) portal vein ligation/split of the liver with a radiofrequency ablation needle; (5) portal vein ligation/radiofrequency ablation of the deportalized liver (portal vein ligation/radiofrequency ablation necrosis in the deportalized liver); (6) portal vein ligation/radiofrequency ablation of the future liver remnant (portal vein ligation/radiofrequency ablation-future liver remnant); and (7) controls. Animals were evaluated on postoperative days 2 and 4. Bodyweight, liver parameters, hepatic regeneration rate, proinflammatory cytokines, hepatocyte proliferation, and gene expression were measured.

RESULTS

Hepatic regeneration rate indicated a steady increase in all intervention groups compared with sham rats (P < .001). At postoperative day 2, the hepatic regeneration rate was significantly higher in the portal vein ligation/radiofrequency ablation necrosis in the deportalized liver group than in the portal vein ligation group (P = .039). On postoperative day 4, we found significant differences between the portal vein ligation group and the ALPPS (P = .015), portal vein ligation/split of the liver with a radiofrequency ablation needle (P = .010), and portal vein ligation/radiofrequency ablation necrosis in the deportalized liver (P = .046) groups. Hepatocyte proliferation was significantly higher at all times compared with sham rats. On postoperative day 4, we found a significantly higher proliferation in groups 3, 4, 5, and 6 compared to portal vein ligation. Gene analysis revealed upregulation of genes involved in cellular proliferation and downregulation of genes involved in cellular homeostasis in all intervention groups. Between the intervention groups, gene expression was nearly identical. Biochemical markers and proinflammatory cytokines were comparable between groups.

CONCLUSION

The surplus liver regeneration after ALPPS is probably mediated through parenchymal damage and subsequent release of growth stimulators, which again upregulates genes involved in cellular regeneration and downregulates genes involved in cellular homeostasis. We also demonstrate that growth of the future liver remnant, comparable to that seen after ALPPS, could be achieved by radiofrequency ablation treatment of the deportalized liver, that is, a procedure in which the initial step in humans can be performed percutaneously.

Liver regeneration is dependent on the extent of hepatectomy

BACKGROUND

The upper limit for the size of hepatectomy is approximately 90% in rats. The aim of the study was to assess quantitatively using stereological methods the impact on liver function, regeneration rate (RR), and hepatocyte proliferation of varying hepatectomy size in a rat model.

MATERIALS AND METHODS

A total of 104 male Wistar rats were subjected to 30%, 70%, or 90% partial hepatectomy, sham operation, or no operation. Euthanization and harvesting of liver tissue and blood took place at postoperative days 1, 3, and 5 (n = 8 per group). Liver-specific biochemistry and RR were evaluated. Hepatocyte proliferation was estimated by immunohistochemical staining for Ki-67 antigen using unbiased stereological principles.

RESULTS

Liver RR in the 90% group increased by a 6.6 fold during the 5 postoperative days compared with only a minor increase in both the 70% and 30% partial hepatectomy groups. The highest number of Ki-67-positive hepatocytes was observed in the 70% group at postoperative day 1 and for the 90% group at postoperative day 3. Prothrombin-proconvertin ratio was significantly lower in the 90% group 1 d after surgery compared with all other groups, however, nearly normalized at postoperative day 5.

CONCLUSIONS

We show that liver RR and the number of proliferating hepatocytes increase, whereas the initial hepatic synthetic capacity decreases with increasing hepatectomy size.

Anti-inflammatory liposomes have no impact on liver regeneration in rats

INTRODUCTION

Surgical resection is the gold standard in treatment of hepatic malignancies, giving the patient the best chance to be cured. The liver has a unique capacity to regenerate. However, an inflammatory response occurs during resection, in part mediated by Kupffer cells, that influences the speed of regeneration. The aim of this study was to investigate the effect of a Kupffer cell targeted anti-inflammatory treatment on liver regeneration in rats.

METHODS

Two sets of animals, each including four groups of eight rats, were included. Paired groups from each set received treatment with placebo, low dose dexamethasone, high dose dexamethasone or low dose anti-CD163 dexamethasone. Subsequently, the rats underwent 70% partial hepatectomy. The two sets were evaluated on postoperative day 2 or 5, respectively. Blood was drawn for circulating markers of inflammation and liver cell damage; liver tissue was sampled for analysis of regeneration rate and proliferation index.

RESULTS

The high dose dexamethasone group had significantly lower body and liver weight than the placebo and anti-CD163-dex groups. There were no differences in liver regeneration rates between groups. Hepatocyte proliferation was completed faster in the placebo group, although this was not significant. The anti-CD163-dex group showed increased blood levels of albumin and alanine aminotransferase and a diminished inflammatory response in terms of significantly reduced haptoglobin, α2-macroglobulin and Interleukine-6.

CONCLUSION

Low dose dexamethasone targeted to Kupffer cells does not affect histological liver cell regeneration after 70% hepatectomy in rats, but reduces the inflammatory response judged by circulating markers of inflammation.

The effect of sorafenib on liver regeneration and angiogenesis after partial hepatectomy in rats

BACKGROUND

Liver regeneration is vital for the survival of patients submitted to extensive liver resection as a treatment of hepatocellular carcinoma (HCC). Sorafenib is a multikinase inhibitor of angiogenesis and cell division, both of which are integral components of liver regeneration. We investigated the effect of preoperative treatment with sorafenib, a drug used for the treatment of HCC, on liver regeneration and angiogenesis in healthy rats, after two-thirds partial hepatectomy (PH2/3).

METHODS

In total 48 Wistar rats received intragastric injections of sorafenib (30 mg/kg/d) or vehicle, underwent PH2/3, and were sacrificed at 48, 96 or 168 hours after that. The regenerative index of the liver remnant was studied, as well as the mitotic index. DNA synthesis and angiogenesis were estimated by immunohistochemistry for the Ki-67 and CD34 antigens, respectively.

RESULTS

Sorafenib reduced significantly the regenerative index at all time points but not the mitotic index at 48, 96 or 168 hours. Deoxyribonucleic acid (DNA) synthesis and angiogenesis were not affected significantly either.

CONCLUSIONS

Sorafenib, when administered preoperatively, reduces incompletely and transiently the regeneration of the liver after PH2/3 in rats. This could mean that sorafenib can be used as neoadjuvant treatment of patients with HCC prior to liver resection, but further experimental and clinical studies are needed to establish the safety of this treatment. Hippokratia 2015; 19 (3): 249-255.

Postoperative but not preoperative treatment with sorafenib inhibits liver regeneration in rats

BACKGROUND

Sorafenib, a multikinase inhibitor, has been shown to halt the growth of hepatocellular carcinoma. The aim of the present study was to investigate the effect of Sorafenib on liver regeneration in healthy rats.

METHODS

In two substudies we examined the effect of pre- or post-operative treatment with Sorafenib (15 mg/kg/d). Wistar rats (n = 120) received either Sorafenib (S) or placebo (P). After 70% partial hepatectomy, the rats were euthanized on postoperative days 2, 4, or 8. Body weight and liver weight were recorded and regeneration rate (RR) calculated. Hepatocyte proliferation was estimated by immunohistochemistry for Ki-67 antigen using unbiased stereological methods.

RESULTS

Eleven animals (9%) died after surgery. In the preoperative substudy, lower body weight gains during the gavage period in the S group were found. No difference between groups S and P regarding liver weight gain, liver RRs, and hepatocyte proliferation on postoperative days 2 and 4 were found. In the postoperative substudy, significantly lower values of liver weight gain, liver RRs, and hepatocyte proliferation were found in the S group.

CONCLUSIONS

In our rat model, Sorafenib did not increase posthepatectomy mortality. Postoperative treatment significantly impaired liver regeneration. Preoperative treatment impaired body weight during the gavage period, but was without effect on liver regeneration.