Octreotide Acetate (Sandostatin) is a potent, long-acting synthetic somatostatin octapeptide analog that inhibits secretion of growth hormone.

Groups treated with Octreotide demonstrated a substantial reduction in tumor volume compared to those administered saline. The Octreotide-PPSG formulation (1.4 mg/kg, i.p.) exhibited a superior antitumor effect over the Octreotide-solution (100 μg/kg, i.p.). Furthermore, Octreotide treatments significantly suppressed the expression levels of SSTR2 and SSTR5 in rats with primary HCC, in comparison to the saline group, with Octreotide-PPSG achieving a more pronounced suppression than Octreotide-solution. In addition, a dose of octreotide acetate markedly lowered serum gastrin levels to about a third of the initial levels within 2 hours, maintaining this effect for around 6 hours. On the 21st day, a sustained-release form of octreotide acetate (5 mg intramuscular, every 4 weeks) was introduced.

Octreotide (acetate) is formulated in saline.MiceThirty mice with HCC xenografts are randomLy divided into three groups: (A) Octreotide-soln group, (B) Octreotide-PPSG group, and (C) control group. Octreotide-soln group receives i.p. injection of 100 μg/kg octreotide-soln once a day and totally for consecutive 14 days. Octreotide-PPSG group receives a single subcutaneous injection of 1.4 mg/kg Octreotide-PPSG, and the injection volume is about 0.2 mL. Control group receives i.p. injection of saline once a day for consecutive 14 days. Treatment starts on the next day after injection of H22 hepatoma cell suspension and maintains for 14 days. Tumor growth is monitored by periodic caliper measurements on day 7 and day 14 post seeding. Tumor volumes (V) are calculated based on the length and width of tumor by Eq. RatTwelve male SD rats are divided into two groups, and housed in standard cages at 25°C, with free access to food and water for a week prior to the experiment. Rats are subcutaneously injected with Octreotidereotide solution (Octreotide-soln) or Octreotide-PPSG at an equivalent single dose of 20 mg/kg. The dose is determined based on the clinical dose of Octreotide-soln in human. Rats are fasted for 12 h before dosing and food is returned approximately 2 h post dosing. Blood samples are collected at predetermined time points using heparinized Eppendorf tubes. Immediately after collection, the blood samples are placed on ice until centrifuged at 3000 g for 10 min within 1 h. The plasma is collected and stored at ?20°C until analysis.