Extended liver resection after preoperative chemotherapy: influence on regeneration and endoplasmic reticulum stress response

Liver regeneration after extensive hepatectomy in rats: effect of preoperative chemotherapy with intravenous 5-fluorouracil

PURPOSE

To evaluate the effect of preoperative intravenous chemotherapy with 5-fluorouracil on liver regeneration in an experimental model of major hepatectomy in rats.

METHODS

Wistar rats were divided into two groups of 20 animals each and submitted to 70% hepatectomy 24 h after intravenous injection of 5-fluorouracil 20 mg/kg (fluorouracil group, FG) or 0.9% saline (control group, CG). After hepatectomy, each group was subdivided into two subgroups of 10 animals each according to the day of sacrifice (24 h or 7 days). Liver weight during regeneration, liver regeneration rate using Kwon formula, and the immunohistochemical markers proliferating cell nuclear antigen (PCNA) and Ki-67 were used to assess liver regeneration.

RESULTS

At early phase (24 h after hepatectomy) it was demonstrated the negative effect of 5-fluorouracil on liver regeneration when assessed by Kwon formula (p < 0.0001), PCNA analysis (p = 0.02). With regeneration process complete (7 days), it was possible to demonstrate the sustained impairment of chemotherapy with 5-fluorouracil on hepatocytes regeneration phenomenon when measured by Kwon formula (p = 0.009), PCNA analysis (p = 0.0001) and Ki-67 analysis (0.001).

CONCLUSIONS

Preoperative chemotherapy with intravenous 5-fluorouracil negatively affected the mechanisms of liver regeneration after major hepatectomy in rats.

Curcumin Reduces Colorectal Cancer Cell Proliferation and Migration and Slows In Vivo Growth of Liver Metastases in Rats

Background: New therapeutic approaches are an essential need for patients suffering from colorectal cancer liver metastases. Curcumin, a well-known plant-derived polyphenol, has been shown to play a role in the modulation of multiple signaling pathways involved in the development and progression of certain cancer cells in vitro. This study aims to assess the anti-tumor effect of curcumin on CC531 colorectal cancer cells, both in vitro and in vivo. Methods: On CC531 cultures, the cell viability and cell migration capacity were analyzed (wound healing test) 24, 48, and 72 h after treatment with curcumin (15, 20, 25, or 30 µM). Additionally, in WAG/RijHsd tumor-bearing rats, the total and individual liver lobe tumor volume was quantified in untreated and curcumin-treated animals (200 mg/kg/day, oral). Furthermore, serum enzyme measurements (GOT, GPT, glucose, bilirubin, etc.) were carried out to assess the possible effects on the liver function. Results: In vitro studies showed curcumin’s greatest effects 48h after application, when all of the tested doses reduced cell proliferation by more than 30%. At 72 h, the highest doses of curcumin (25 and 30 µM) reduced cell viability to less than 50%. The wound healing test also showed that curcumin inhibits migration capacity. In vivo, curcumin slowed down the tumor volume of liver implants by 5.6-fold (7.98 ± 1.45 vs. 1.41 ± 1.33; p > 0.0001). Conclusions: Curcumin has shown an anti-tumor effect against liver implants from colorectal cancer, both in vitro and in vivo, in this experimental model.

Sinusoidal obstruction syndrome in the animal model: influence on liver surgery

PURPOSE

In recent years, multimodal treatment approaches have led to an increased median survival time of patients with colorectal liver metastases. In particular, this results from new perioperative chemotherapy regimens, which in turn are accompanied by an increased risk of perioperative bleeding and/or liver failure due to the hepatotoxic side effects. Nineteen to 58 % of patients treated with oxaliplatin develop sinusoidal obstruction syndrome (SOS). The influence of preexisting SOS on liver surgery remains controversial.

METHODS

Animals were operated 4 days after SOS induction with monocrotaline and received either vascular occlusion in the form of Pringle maneuver (PM) or hepatectomy (LR; 70 %) or a combination of both (LR + PM). Postoperative liver function was assessed by determination of liver enzyme levels, bile production, and tissue oxygen saturation.

RESULTS

Preexisting SOS impaired morbidity after liver resection, reflected by elevated liver enzyme levels, reduced bile secretion, and low liver tissue oxygenation levels. Mortality was increased by up to 25 %. Additional ischemia in the form of PM showed no further impact in the LR ± PM group compared to LR alone.

CONCLUSION

PM without LR results in high enzyme distribution in the SOS group. SOS significantly affects the outcome after liver resection in our experimental rat model only without PM and showed no protective effect in ischemia in the form of PM.