ABSTRACT
In this study, the maximum tolerated dose (MTD) of lobaplatin (LBP) when it was combined with docetaxel (TXT) for the treatment of solid tumours that had progressed following chemotherapy was determined, and toxicities to this regimen were evaluated. A modified Fibonacci method was used for the dose escalation of LBP. The patients received TXT (at a fixed dose of 60 mg/m2) on day one (d1) and LBP (at an initial tested dose of 30 mg/m2) on day two (d2) of a treatment cycle that was repeated every 21 days. Each dose group consisted of at least three cases. In the absence of dose-limiting toxicity (DLT), we proceeded to the next dose group, with a dose increment of 5 mg/m2 between groups, until DLT occurred. The dose immediately below the dose that produced DLT was regarded as the MTD. The 17 patients examined in this study completed a total of 58 cycles of chemotherapy, and a total of three dose-escalation groups (30 mg/m2 LBP, 35 mg/m2 LBP, and 40 mg/m2 LBP) were established. The main adverse event that was observed was myelosuppression. DLT occurred in four patients, including three patients in the 40 mg/m2 LBP group and one patient in the 35 mg/m2 LBP group. In total, three out of the four patients in the 40 mg/m2 LBP group exhibited DLT. We determined that the treatment administered to the 35 mg/m2 LBP group represented the MTD. Thus, our phase I trial revealed that the MTD for the tested LBP combination regimen was 35 mg/m2 LBP and 60 mg/m2 TXT. This regimen resulted in mild adverse reactions and favourable patient tolerance. Therefore, we recommend the use of these dosages in phase II clinical trials.
ABSTRACT
Gastric cancer is the fourth most common type of cancer globally and accounts for the second highest cancer-associated mortality rate in the world. Current treatment strategies for gastric cancer include surgery, radiotherapy, chemotherapy and targeted therapy. Intraperitoneal (IP) chemotherapy may increase the IP concentrations of chemotherapy drugs and reduce the systemic toxicity. At present, IP chemotherapy is used to treat patients with advanced gastric cancer, which has a high rate of peritoneal recurrence. The present study evaluated the feasibility of using docetaxel, cisplatin and fluorouracil (DCF) in an IP and intravenous (IV) dual chemotherapy regimen for the treatment of advanced gastric cancer. The treatment-associated adverse reactions and preliminary efficacy were reported. The first dose level utilized the full dose of DCF: Docetaxel, day one, 45 mg/m2 (IP) and day eight, 30 mg/m2 (IV); cisplatin (DDP), day one, 75 mg/m2 (IP); and fluorouracil (FU), days one to five, 750 mg/m2 (continuous IV). A total of six patients were treated at this level and two patients withdrew due to serious adverse reactions. Taking into account that the the tolerated doses used in combination regimens for Eastern populations are lower than that of the corresponding doses for Western populations, the dosages of the three drugs were all reduced by 20% in the application of the second dose level: Docetaxel, day one, 30 mg/m2 (IP) and day eight, 30 mg/m2 (IV); DDP, day two, 60 mg/m2 (IP); and FU, days one to five, 600 mg/m2 (continuous IV). A total of 26 patients were treated at this level. The main adverse reaction was bone marrow suppression, with grade III/IV neutropenia, leukopenia and febrile neutropenia accounting for 61.5, 53.8 and 19.2% of reactions, respectively, and grade III/IV anemia and thrombocytopenia accounting for 19.2 and 15.4% of reactions, respectively. Gastrointestinal adverse reactions primarily consisted of abdominal pain, with grade III/IV abdominal pain accounting for 30.8% of reactions. Only 7.7% of the patients withdrew from the treatment. The median time to progression (TTP) was five months [95% confidence interval (CI), 1.0-9.0 months], and the median overall survival (OS) was nine months (95% CI, 7.4-10.6 months). It was concluded that the DCF regimen with reduced dosage should be applied. IP and IV dual chemotherapy for the treatment of unresectable advanced gastric cancer is tolerated and demonstrated a good initial efficacy. Strategies for mitigating and reducing the adverse gastrointestinal reactions, particularly abdominal pain, may be the focus of future studies.
ABSTRACT
Ras mutations contribute to human cancer development. The present study assessed the Ras V12 mutation in hepatocellular carcinoma (HCC) cells and the role of its silencing in vitro and in nude mouse xenografts. HCC BEL7402 cells expressed mutations of V12 (Val/Gly) and wild-type H-Ras, whereas SMMC7721 cells only expressed wild-type H-Ras. The shRNA constructs specifically silenced mutated H-Ras expression in BEL7402 cells, but did not affect wild-type Ras expression in SMMC7721 cells. Silencing of mutated H-Ras expression reduced BEL7402 cell viability, induced apoptosis and arrested cells at the G0/G1 phase of the cell cycle. Expression of phospho-Akt was also significantly decreased, while several apoptotic proteins were also activated. Furthermore, sensitivity of stably H1-shRNA and H2-shRNA transfected BEL7402 cells to cisplatin treatment was increased by 7.19- and 5.39-fold, respectively, compared to that in the negative control cells, and apoptosis-related gene expression was also altered. Intraperitoneal administration of cisplatin led to a substantial reduction in HCC xenograft growth by 81 and 77% in the H1-shRNA and H2-shRNA transfected tumor xenografts, respectively, compared to a 37% reduction in mice bearing negative control tumor cells. These data demonstrate that knockdown of mutated H-Ras V12 expression induced chemosensitivity of HCC cells to cisplatin treatment in vitro and in vivo.
