Effects of granulocyte-colony stimulating factor on peritoneal defense mechanisms and bacterial translocation after administration of systemic chemotherapy in rats

AIM: To investigate the effects of granulocyte-colony stimulating factor (G-CSF) on peritoneal defense mechanisms and bacterial translocation after systemic 5-Fluorouracil (5-FU) administration.

METHODS: Thirty Wistar albino rats were divided into three groups; the control, 5-FU and 5-FU + G-CSF groups. We measured bactericidal activity of the peritoneal fluid, phagocytic activity of polymorphonuclear leucocytes in the peritoneal fluid, total peritoneal cell counts and cell types of peritoneal washing fluid. Bacterial translocation was quantified by mesenteric lymph node, liver and spleen tissue cultures.

RESULTS: Systemic 5-FU reduced total peritoneal cell counts, neutrophils and macrophage numbers. It also altered bactericidal activity of the peritoneal fluid and phagocytic activity of polymorphonuclear leucocytes in the peritoneal fluid. 5-FU also caused significant increase in frequencies of bacterial translocation at the liver and mesenteric lymph nodes. G-CSF decreased bacterial translocation, it significantly enhanced bactericidal activity of the peritoneal fluid and phagocytic activity of polymorphonuclear leucocytes in the peritoneal fluid. It also increased total peritoneal cell counts, neutrophils and macrophage numbers.

CONCLUSION: Systemic 5-FU administration caused bacterial translocation, decreased the bactericidal activity of peritoneal fluid and phagocytic activity of polymorphonuclear leucocytes in the peritoneal fluid. G-CSF increased both bactericidal activity of the peritoneal fluid and phagocytic activity of polymorphonuclear leucocytes in the peritoneal fluid, and prevented the bacterial translocation. We conclude that intraperitoneal GCSF administration protects the effects of systemic 5-FU on peritoneal defense mechanisms.

5-Fluorouracil-related enhancement of adenoviral infection is Coxsackievirus-adenovirus receptor independent and associated with morphological changes in lipid membranes

AIM: To evaluate the mechanism underlying the effects of 5-Fluorouracil (5-FU) on adenoviral infection.

METHODS: Low and high Coxsackievirus-Adenovirus Receptor (CAR) expressing human colon carcinoma cell lines were treated with 5-FU and two E1-deleted adenoviral constructs, one transferring GFP (Ad/CMV-GFP) the other bax (Ad/CEA-bax). The number of infected cells were monitored by GFP expression. To evaluate the effects of 5-FU in a receptor free system, Ad/GFP were encapsulated in liposomes and treated with 5-FU. Ad/GFP release was estimated with PCR and infection of 293 cells with the supernatant. Electron microscopy of the Ad5-GFP-liposome complex was made to investigate morphological changes of the liposomes after 5-FU.

RESULTS: Infection rates of all cell lines increased from 50% to 98% with emerging 5-FU concentrations. The enhanced viral uptake was independent of the CAR expression. Additionally, 5-FU treated liposomes released 2-2.5 times more adenoviruses. Furthermore, 5-FU-treated liposomes appeared irregular and porous-like.

CONCLUSION: adenoviral uptake is enhanced in the presence of 5-FU irrespective of CAR and is associated with morphological changes in membranes making the combination of both a promising option in gene therapy.

Role of recombinant adenovirus IkBaM in 5-fluorouracil-induced apoptosis of gastric carcinoma SGC-7901 cells

AIM: To investigate the role of recombinant adenovirus IkBaM (Ad-IkBaM) on the apoptosis of gastric carcinoma SGC-7901 cells induced by 5-fluorouracil (5-FU) as well as the possible mechanism.

METHODS: The cultured SGC-7901 cells were divided into group A, B and C. The cells in group A and B were infected with Ad-IkBaM and Ad-IkBa, respectively, and those in group C served as controls. 5-FU was added to each group at the concentration of 5 mg/L, respectively. Electrophoretic mobility shift assays were used to detect the activation of nuclear facter kappa B (NF-κB) in all the groups, and the 5-FU-induced apoptosis of SGC-7901 cells was tested by MTT and TUNEL method.

RESULTS: After 5-FU treatment, NF-κB was activated in gastric carcinoma cells, but in the cells infected with Ad-IkBaM, the activity of NF-κB was inhibited. MTT assay indicated that the apoptosis rate of cells infected with Ad-IkBaM (56.36% ± 0.60%) was significantly higher than that of cells infected with Ad-IkBa (47.50% ± 1.42%), or without infection (42.95% ± 1.27%) (P < 0.001). TUNEL method showed that the apoptosis rate was 29.7% ± 2.5% in the cells infected with Ad-IkBaM, which was also significantly higher than that of cells infected with Ad-IkBa (20.0% ± 2.6%) or without infection (12.3% ± 1.1%) (P < 0.01). Therefore, infection with Ad-IkBaM markedly promoted the apoptosis induced by 5-FU.

CONCLUSION: Infection with Ad-IkBaM can effectively inhibit the activation of NF-κB in human SGC-7901 cells, and increase the apoptosis induced by 5-FU.

Expression and clinical significance of thymidine phosphorylase and dihydropyrimidine dehydrogenase in colorectal carcinoma

AIM: To investigate the expression levels and their clinical significances of thymidine phosphorylase (TP) and dihydropyrimidine dehydrogenase (DPD) in colorectal carcinoma.

METHODS: Enzyme linked immunosorbent assay (ELISA) and immunohistochemistry were used to detect the expression of TP and DPD protein in 54 cases of colorectal carcinoma and the corresponding cancer-adjacent tissues, and the correlations between TP/DPD expression and clinicopathological features were statistically analyzed.

RESULTS: The level of TP expression was significantly higher in cancer tissues than that in cancer-adjacent tissues (1026 ± 492 vs 387 ± 226 μkat/g protein, P < 0.01), but DPD expression was not markedly different between cancer and cancer-adjacent tissues (P = 0.510). ELISA showed that TP contents were correlated with lymph node metastasis (P = 0.003) and Dukes stages (P = 0.026), whereas DPD tended to be highly expressed in males (P = 0.023) and mucinous adenocarcinoma (P = 0.013). Immunohistochemistry showed that the positive rates of TP and DPD expression were 53.70%(29/54) and 44.44%(24/54), respectively, in colorectal carcinoma and TP seemed to be highly expressed in patients with lymph node metastasis (P = 0.016) and late Dukes stages (P = 0.075), while DPD expression had significant correlation with the gender (P = 0.044).

CONCLUSION: TP level is higher in colorectal cancer tissues than that in normal ones and it is correlated with clinical staging. DPD level has no difference between colorectal cancer tissues and normal tissues, but it is highly expressed in males.

A phase II study of irinotecan, 5-fluorouracil and leucovorin for treatment in patients with previously untreated advanced colorectal cancer

PURPOSE

We prospectively conducted a non-randomized phase II trial to evaluate the efficacy and safety of combination irinotecan, leucovorin (LV) and 5-fluorouracil (FU) as a first-line regimen for treating patients with previously untreated advanced colorectal cancer (CRC).

MATERIALS AND METHODS

Twenty-six previously untreated patients with advanced, recurrent or metastatic CRC were enrolled in this study. The patients received either irinotecan 180 mg/m(2) on day 1 with LV bolus of 200 mg/m(2) and FU bolus of 400 mg/m(2), and this was followed by FU continuous infusion of 600 mg/m(2) on day 1 and day 2 (the FOLFIRI regimen), or they were treated with LV bolus of 400 mg/m(2) and FU bolus of 400 mg/m(2) followed by FU continuous infusion of 2,400 mg/m(2) for 46 hours (the simplified FOLFIRI regimen), and these treatments were repeated every 2 weeks until disease progression.

RESULTS

The objective response rate was 23.1% (6/26) respectively, for both treatments. The median time to progression was 5.3 months (range: 0.4 approximately 19.9), and the overall survival was 11.2 months (range: 0.5 approximately 52.3). The prognostic factor for longer survival was the Eastern Cooperative Oncology Group (ECOG) performance status (PS). The non-hematological toxicities were similar for both treatment groups, with more frequent grade >or=3 neutropenia being noted for the simplified FOLFIRI regimen.

CONCLUSION

The biweekly irinotecan based regimen was demonstrated to have a moderate antitumor activity with acceptable toxicity profiles, and the ECOG PS was the independent prognostic factor.

Combination chemotherapy of oxaliplatin, 5-fluorouracil and low dose leucovorin in patients with advanced colorectal cancer

PURPOSE

The aim of this study was to evaluate the efficacy and tolerability of the oxaliplatin, 5-fluorouracil (5-FU) and low dose leucovorin (LV) combination in patients with advanced colorectal cancer.

MATERIALS AND METHODS

Patients with unresectable or recurrent colorectal carcinomas were prospectively accrued. Up to one prior chemotherapy regimen was allowed. Patients received oxaliplatin, 85 mg/m(2), administered as a 2-hour infusion on day 1, followed by LV, 20 mg/m(2), as a bolus and 5-FU, 1,500 mg/m(2), via continuous infusion for 24 hours on days 1 and 2. Treatment was repeated every 2 weeks until disease progression or adverse effects prohibited further therapy.

RESULTS

Between August 1999 and May 2004, 31 patients were enrolled in this study. Of the patients enrolled, 24 and 31 were evaluable for tumor response and survival analysis, respectively. The patients' characteristics included a median age of 59, with 6 (19%) having had prior chemotherapy. No patient achieved a complete response, but nine (38%) attained a partial response. Seven (29%) patients maintained a stable disease and 8 (33%) experienced increasing disease. The median duration of the response was 6 months. After a median follow-up of 9.6 months, the median time to progression was 3.8 months, with a median survival of 10.7 months. The hematological toxicities were mild to moderate, with no treatment-related mortality or infection. The major non-hematological toxicity was gastrointestinal toxicity.

CONCLUSION

The combination chemotherapy of oxaliplatin, low dose LV and continuous infusion of 5-FU is safe and has a cost-benefit, but is a moderately effective regimen in advanced colorectal cancer. A randomized trial comparing low and high dosages of leucovorin in the FOLFOX regimen is warranted.

Re-evaluation of antitumor effects of combination chemotherapy with interferon-α and 5-fluorouracil for advanced hepatocellular carcinoma

AIM: To evaluate the efficacy of combination chemotherapy with interferon-α (IFN α ) and 5-fluorouracil (5-FU) in patients with advanced hepatocellular carcinoma (HCC).

METHODS: Twenty-eight HCC patients in advanced stage were enrolled in the study. They were treated with IFNα / 5-FU combination chemotherapy. One cycle of therapy lasted for 4 wk. IFNα (3×10⁶ units) was subcutaneously injected thrice weekly on days 1, 3, and 5 for 3 wk, and 5-FU (500 mg/d) was administered via the proper hepatic artery for 5 consecutive days per week for 3 wk. No drugs were administered during the 4^th wk. The effect of combination chemotherapy was evaluated in each patient after every cycle based on the reduction of tumor volume.

RESULTS: After the 1^st cycle of therapy, 16 patients showed a partial response (PR, 57.1%) but none showed a complete response (CR, 0%). At the end of therapy, the number of patients who showed a CR, PR, or no response (NR) was 1, 10, and 17, respectively. The response rate for therapy (CR+PR) was 21.5%. Biochemical tests before therapy were compared between responsive (CR+PR) and non-responsive (NR) patients, but no significant differences were found for any of the parameters examined, indicating that no reasonable predictors could be identified in our analysis.

CONCLUSION: Attempts should be made to discriminate between responders and non-responders by evaluating tumor size after the first cycle of IFNα /5-FU combination chemotherapy. For non-responders, therapy should not proceed to the next cycle, and instead, different combination of anticancer drugs should be explored.

Successful treatment of advanced hepatocellular carcinoma by combined administration of 5-fluorouracil and pegylated interferon-α

We report a case of hepatocellular carcinoma (HCC) treated successfully by transarterial chemoembolization (TACE) followed by combination therapy of 5-fluorouracil (5-FU) and pegylated interferon-α (PEG-IFN-α). In the present case, the patient had massive and advanced HCC with a diameter of over 8 cm located in segment 7 (S7) of the liver. Furthermore, the tumor invaded into the major branch of the portal vein (Vp3). After TACE, combined administration of 5-FU and PEG-IFN-α was performed for 5 mo. HCC was totally eradicated and the serum levels of tumor markers were markedly decreased by the treatment. Although it has been reported that the combined use of conventional IFN-α and 5-FU showed striking effects on HCC in some cases, this case may suggest the more promising effect of PEG-IFN-α with a long-lasting effect, in the combined use with 5-FU for the treatment of massive advanced HCC.

Anti-hepatocarcinoma effects of 5-fluorouracil encapsulated by galactosylceramide liposomes in vivo and in vitro

AIM: To study the anti-hepatocarcinoma effects of 5-fluorouracil (5-Fu) encapsulated by galactosylceramide liposomes (5-Fu-GCL) in vivo and in vitro.

METHODS: Tumor-bearing animal model and HepA cell line were respectively adopted to evaluate the anti-tumor effects of 5-Fu-GCL in vivo and in vitro. Tumor cell growth inhibition effects of 5-Fu-GCL in vitro were assessed by cell viability assay and MTT assay. In vivo experiment, the inhibitory effects on tumor growth were evaluated by tumor inhibition rate and animal survival days. High performance liquid chromatography was used to detect the concentration-time course of 5-Fu-GCL in intracellular fluid in vitro and the distribution of 5-Fu-GCL in liver tumor tissues in vivo. Apoptosis and cell cycle of tumor cells were demonstrated by flow cytometry.

RESULTS: In vitro experiment, 5-Fu-GCL (6.25-100 μmol/L) and free 5-Fu significantly inhibited HepA cell growth. Furthermore, IC₅₀ of 5-Fu-GCL (34.5 μmol/L) was lower than that of free 5-Fu (51.2 μmol/L). In vivo experiment, 5-Fu-GCL (20, 40, 80 mg/kg) significantly suppressed the tumor growth in HepA bearing mice model. Compared with free 5-Fu, the area under curve of 5-Fu-GCL in intracellular fluid increased 2.6 times. Similarly, the distribution of 5-Fu-GCL in liver tumor tissues was significantly higher than that of free 5-Fu. After being treated with 5-Fu-GCL, the apoptotic rate and the proportion of HepA cells in the S phase increased, while the proportion in the G0/G1 and G2/M phases decreased.

CONCLUSION: 5-Fu-GCL appears to have anti-hepato-carcinoma effects and its drug action is better than free 5-Fu. Its mechanism is partly related to increased drug concentrations in intracellular fluid and liver tumor tissues, enhanced tumor cell apoptotic rate and arrest of cell cycle in S phase.

Phase II study of irinotecan, 5-fluorouracil, and leucovorin in relapsed or metastatic colorectal cancer as first-line therapy

BACKGROUND

The purpose of this study was to assess the efficacy and toxicity of biweekly irinotecan plus 5-fluorouracil (FU) and leucovorin (LV) in patients with relapsed or metastatic colorectal cancer.

MATERIALS AND METHODS

Between March 2002 and May 2004, 24 patients with histologically confirmed relapsed or metastatic colorectal cancer were enrolled in this study. One chemotherapy cycle consisted of irinotecan 180 mg/m(2) on days 1 and 15; 5-FU 400 mg/m(2) bolus IV with 600 mg/m(2) by a 22 hour intravenous infusion on days 1, 2, 15 and 16; and leucovorin 20 mg/m(2) on days 1, 2, 15 and 16, every 4 weeks.

RESULTS

The median age of the 24 was 57.5 years (range, 38 approximately 69). Their metastatic sites included: the liver (62.5%), lung (20.8%), peritoneum (16.7%), lymph node (12.5%), ovary (8.3%) and pelvis/vagina (8.3%). Twenty-two patients were evaluable for a response. Six and 7 patients achieved partial responses and stable diseases, respectively. The overall response rate was 27.3% (95% Confidence interval; 10.3 approximately 44.5%). The median follow-up duration for surviving patients was 14.7 months (range, 1.7 approximately 26.5). Median overall survival (OS) and 1-year OS rates were 19 months and 86.3%, respectively. Median response duration and median progression free survival were 7.47 and 5.57 months, respectively. A total of 83 cycles (median 4 cycles) were administered. The main non-hematologic toxicities were nausea/vomiting (44.5%/18.1%) and diarrhea (8.4%). The most common hematologic toxicity was NCI grade I/II anemia (31.3%) and grade I/II neutropenia was 10.8%. There was no life-threatening toxicity.

CONCLUSION

The results suggested that irinotecan, 5-FU and leucovorin combination chemotherapy in a biweekly schedule is a practical and tolerable treatment option in patients with advanced colorectal cancer.

Randomized phase III trial of cisplatin, epirubicin, leucovorin, 5-fluorouracil (PELF) combination versus 5-fluorouracil alone as adjuvant chemotherapy in curative resected stage III gastric cancer

PURPOSE

The combination of cisplatin, epirubicin, leucovorin and 5-fluorouracil (PELF) administration, as adjuvant chemotherapy after curative resection for gastric cancer, was compared with 5-fluorouracil (5-FU) administration alone. This paper reports the results of a prospective randomized comparison of the two regimens, PELF and 5-FU.

METHODS

From August 1996 to July 1999, 54 patients were selected subsequent to being diagnosed with stage III cancer after a curative resection for gastric cancer. The patients were stratified according to stage IIIA/IIIB and subtotal/total gastrectomy, and then they were randomized into each treatment group, i.e. the PELF or 5-FU alone groups.

RESULTS

54 assessable patients were enrolled in this study: 28 received PELF and 26 received 5-FU alone. 12 patients relapsed in each group and the median follow-up duration was 42 months (range: 10 approximately 77 months). The overall survival rate and disease-free survival rate (DFS) were not significantly different between two groups, (5-year survival of PELF vs. 5-FU: 57% vs. 64%, 5-year DFS: 54% vs. 51%). The PELF combination was more toxic in terms of anemia, anorexia, nausea and diarrhea than the 5-FU.

CONCLUSIONS

This study showed that the PELF combination, as an adjuvant therapy for gastric cancer after a curative resection, was a less effective treatment, and it had more toxic effects than the 5-FU.

Combination Chemotherapy of Oxaliplatin, 5-Fluorouracil, and Leucovorin in 5-Fluorouracil-Pretreated Patients with Metastatic Colorectal Cancer

PURPOSE

To evaluate the efficacy and toxicity of oxaliplatin in combination with 5-fluorouracil (5-FU) and leucovorin (LV) in patients with metastatic colorectal cancer who previously treated with 5-FU-based chemotherapy.

MATERIALS AND METHODS

Between April 1999 and January 2001, thirty-two patients were enrolled in this study. Oxaliplatin 130 mg/m2 was given intravenously (IV) on day 1 as was 5-FU 500 mg/m2 IV followed by continuous infusion of 5-FU 3,000 mg/m2 and LV 100 mg/m2 for 48 hours administered every 3 weeks. Six patients had received 5-FU as an adjuvant setting and 26 patients as a palliative regimen.

RESULTS

The median age of the patients was 50 years (range; 19-69) and the dominant sites of metastasis were the liver, lung or both in 9, 5 and 2 patients respectively. In 30 evaluable patients, the overall response rate was 27% including 1 complete response and 7 partial responses. The median response duration was 28 weeks (95% confidence interval; 22~34 weeks) and the median progression free survival of all patients was 24 weeks (95% confidence interval; 15~33 weeks). A median 5 cycles (range; 2~9) and total 155 cycles were performed in 32 patients. 150 cycles were evaluable for toxicity. The most common hematologic toxicity was grade 1~2 anemia in 78 cycles (52%). Leukopenia (39%) and thrombocytopenia (23%) were fully reversible. The most common non-hematologic toxicity was nausea/vomiting (43/30%) followed by diarrhea (23%), hepatotoxicity (21%) and neurotoxicity (21%). One patient ceased therapy due to grade 4 diarrhea. No other severe toxicity interrupted this treatment.

CONCLUSION

Oxaliplatin, 5-FU and LV in combination showed significant activity in previously treated metastatic colorectal cancer with favorable toxicity.