Chemoprevention of skin cancer using low HLB surfactant nanoemulsion of 5-fluorouracil: a preliminary study

Oral delivery of 5-fluorouracil (5-FU) is difficult due to its serious adverse effects and extremely low bioavailability. Therefore, the aim of present investigation was to develop and evaluate low HLB surfactant nanoemulsion of 5-FU for topical chemoprevention of skin cancer. Low HLB surfactant nanoemulsions were prepared by oil phase titration method. Thermodynamically stable nanoemulsions were characterized in terms of droplet size distribution, zeta potential, viscosity and refractive index. Selected formulations and control were subjected to in vitro skin permeation studies through rat skin using Franz diffusion cells. Optimized formulation F9 was subjected to stability and in vitro cytotoxic studies on melanoma cell lines. Enhancement ratio was found to be 22.33 in formulation F9 compared with control and other formulations. The values of steady state flux and permeability coefficient for formulation F9 were found to be 206.40 ± 14.56 µg cm(-2) h(-1) and 2.064 × 10(-2) ± 0.050 × 10(-2 )cm h(-1), respectively. Optimized formulation F9 was found to be physical stable. In vitro cytotoxicity studies on SK-MEL-5 cancer cells indicated that 5-FU in optimized nanoemulsion is much more efficacious than free 5-FU. From these results, it can be concluded that the developed nanoemulsion might be a promising vehicle for chemoprevention of skin cancer.

Cooperative inhibitory effect of sinomenine combined with 5-fluorouracil on esophageal carcinoma

AIM: To investigate the inhibitory effects of sinomenine (SIN) combined with 5-fluorouracil (5-FU) on esophageal carcinoma in vitro and in vivo.

METHODS: Esophageal carcinoma (Eca-109) cells were cultured in DMEM. The single or combined growth inhibition effects of SIN and 5-FU on the Eca-109 cells were examined by measuring the absorbance of CCK-8 dye in living cells. Hoechst 33258 staining and an Annexin V/PI apoptosis kit were used to detect the percentage of cells undergoing apoptosis. Western blotting was used to investigate the essential mechanism underlying SIN and 5-FU-induced apoptosis. SIN at 25 mg/kg and 5-FU at 12 mg/kg every 3 d, either combined or alone, was injected into nude mice and tumor growth inhibition and side effects of the drug treatment were observed.

RESULTS: SIN and 5-FU, both in combination and individually, significantly inhibited the proliferation of Eca-109 cells and induced obvious apoptosis. Furthermore, the combined effects were greater than those of the individual agents (P < 0.05). Annexin V/PI staining and Hoechst 33258 staining both indicated that the percentage of apoptotic cells induced by SIN and 5-FU combined or alone were significantly different from the control (P < 0.05). The up-regulation of Bax and down-regulation of Bcl-2 showed that the essential mechanism of apoptosis induced by SIN and 5-FU occurs via the mitochondrial pathway. SIN and 5-FU alone significantly inhibited the growth of tumor xenografts in vivo, and the combined inhibition rate was even higher (P < 0.05). During the course of chemotherapy, no obvious side effects were observed in the liver or kidneys.

CONCLUSION: The combined effects of SIN and 5-FU on esophageal carcinoma were superior to those of the individual compounds, and the drug combination did not increase the side effects of chemotherapy.

Selenocystine potentiates cancer cell apoptosis induced by 5-fluorouracil by triggering reactive oxygen species-mediated DNA damage and inactivation of the ERK pathway

5-Fluorouracil (5-FU)-based chemotherapy as a first-line treatment is quite limited, because of its inefficiency and clinical resistance to it. The search for chemosensitizers that could augment its efficiency and overcome the drug resistance to 5-FU has kindled great interest among scientists. Selenocystine (SeC), a naturally occurring selenoamino acid, displayed broad-spectrum anticancer activity in our previous studies. This study demonstrates that SeC acts as an effective enhancer of 5-FU-induced apoptosis in A375 human melanoma cells through induction of mitochondria-mediated apoptosis with the involvement of DNA damage-mediated p53 phosphorylation and ERK inactivation. Pretreatment of the cells with SeC significantly enhanced 5-FU-induced loss of mitochondrial membrane potential (∆ψm) by regulating the expression levels of Bcl-2 family proteins. SeC and 5-FU in combination also triggered cell oxidative stress through regulation of the intracellular redox system and led to DNA damage and inactivation of ERK and AKT. Moreover, inhibitors of ERK and AKT effectively enhanced the apoptotic cell death induced by the combined treatment. However, pretreatment of the cells with glutathione reversed the apoptosis induced by SeC and 5-FU and recovered the expression of ERK and AKT inactivation, which revealed the important role of reactive oxygen species in cell apoptosis and regulation of ERK and AKT pathways. Taken together, our results suggest that a strategy of using SeC and 5-FU in combination could be a highly efficient way to achieve anticancer synergism.

Attenuation of nucleoside and anti-cancer nucleoside analog drug uptake in prostate cancer cells by Cimicifuga racemosa extract BNO-1055

This study aimed to investigate the mechanisms underlying the anti-proliferative effects of the ethanolic Cimicifuga racemosa extract BNO-1055 on prostate cells and evaluate its therapeutic potential. BNO-1055 dose-dependently attenuated cellular uptake and incorporation of thymidine and BrdU and significantly inhibited cell growth after long-time exposure. Similar results were obtained using saponin-enriched sub-fractions of BNO-1055. These inhibitory effects of BNO-1055 could be mimicked using pharmacological inhibitors and isoform-specific siRNAs targeting the equilibrative nucleoside transporters ENT1 and ENT2. Moreover, BNO-1055 attenuated the uptake of clinically relevant nucleoside analogs, e.g. the anti-cancer drugs gemcitabine and fludarabine. Consistent with inhibition of the salvage nucleoside uptake pathway BNO-1055 potentiated the cytotoxicity of the de novo nucleotide synthesis inhibitor 5-FU without significantly altering its uptake. Collectively, these data show for the first time that the anti-proliferative effects of BNO-1055 result from hindered nucleoside uptake due to impaired ENT activity and demonstrate the potential therapeutic use of BNO-1055 for modulation of nucleoside transport.

Ultra high-resolution anterior segment optical coherence tomography in the diagnosis and management of ocular surface squamous neoplasia

The development of optical coherence tomography (OCT) technology has helped to usher in a new era of in vivo diagnostic imaging of the eye. The utilization of OCT for imaging of the anterior segment and ocular surface has evolved from time-domain devices to spectral-domain devices with greater penetrance and resolution, providing novel images of anterior segment pathology to assist in diagnosis and management of disease. Ocular surface squamous neoplasia (OSSN) is one such pathology that has proven demonstrable by certain anterior segment OCT machines, specifically the newer devices capable of performing ultra high-resolution OCT (UHR-OCT). Distinctive features of OSSN on high resolution OCT allow for diagnosis and differentiation from other ocular surface pathologies. Subtle findings on these images help to characterize the OSSN lesions beyond what is apparent with the clinical examination, providing guidance for clinical management. The purpose of this review is to examine the published literature on the utilization of UHR-OCT for the diagnosis and management of OSSN, as well as to report novel uses of this technology and potential directions for its future development.

Targeted local simultaneous iontophoresis of chemotherapeutics for topical therapy of head and neck cancers

The objective was to investigate the feasibility of using buccal iontophoresis for the simultaneous delivery of chemotherapeutic agents with a view to developing a new approach to treat head and neck cancers. Short duration cathodal iontophoresis of 5-fluorouracil (5-FU; 20mM) and leucovorin (LV; 10 mM) at 1 mA/cm(2) for 10 or 20 min from aqueous solution and a 2% hydroxyethyl cellulose gel at pH 7.6 was evaluated using bovine mucosa in vitro. Iontophoresis resulted in a statistically significant increase in the mucosal deposition of both drugs as compared to passive diffusion (Student's t-test, α=0.05); in each case, drug delivery was selective for deposition with no permeation being observed. After 20 min of iontophoresis, there was an ~ 8-fold enhancement for 5-FU (1.46 ± 0.86 and 11.93 ± 3.81 μg/cm(2), respectively) and a 3-fold increase for LV (8.31 ± 2.44 and 25.08 ± 6.89 μg/cm(2), respectively) when using aqueous solutions. The same trend was observed when the gel was applied for 10 min; passive delivery of 5-FU from the gel resulted in non-detectable levels in the mucosa, while 4.62 ± 1.76 μg/cm(2) were deposited in the mucosa following iontophoresis. Similarly, iontophoretic delivery of LV from the gel resulted in ~ 3-fold higher deposition as compared to passive diffusion (6.71 ± 1.36 and 21.12 ± 9.94 μg/cm(2), respectively). No drug permeation was observed in either case. In conclusion, iontophoresis can be used for targeted topical delivery of chemotherapeutics to the buccal mucosa and may enable less invasive local therapy of head and neck cancers.

Antitumor effects of anti-CD40/CpG immunotherapy combined with gemcitabine or 5-fluorouracil chemotherapy in the B16 melanoma model

Our previous studies demonstrated that anti-CD40 mAb (anti-CD40) can synergize with CpG oligodeoxynucleotides (CpG) to mediate antitumor effects by activating myeloid cells, such as macrophages in tumor-bearing mice. Separate teams have shown that chemotherapy with gemcitabine (GEM) or 5-fluorouracil (5-FU) can reduce tumor-induced myeloid-derived suppressor cells (MDSC) in mice. In this study we asked if the same chemotherapy regimens with GEM or 5-FU will enhance the antitumor effect of anti-CD40 and CpG. Using the model of B16 melanoma growing intraperitoneally in syngeneic C57BL/6 mice, we show that these GEM or 5-FU treatment regimens reduced MDSC in the peritoneal cavity of tumor-bearing mice. Treatment of mice with GEM or 5-FU did not significantly affect the antitumor function of macrophages as assessed in vitro. In vivo, treatment with these GEM or 5-FU regimens followed by anti-CD40/CpG resulted in antitumor effects similar to those of anti-CD40/CpG in the absence of GEM or 5-FU. Likewise, reduction of MDSC by in vivo anti-Gr-1 mAb treatment did not significantly affect anti-CD40/CpG antitumor responses. Together, the results show that the GEM or 5-FU chemotherapy regimens did not substantially affect the antitumor effects induced by anti-CD40/CpG immunotherapy.

Enhanced antitumor and reduced toxicity effect of Schisanreae polysaccharide in 5-Fu treated Heps-bearing mice

Previous study indicated that the refined polysaccharide from Schisandra could improve the CTX-induced inhibition of T and B lymphocytes proliferation. Accordingly, the enhanced antitumor and reduced toxicity effects of a low molecular weight purified polysaccharide from Schisandra (SCPP11) were investigated in 5-fluorouracil (5-Fu) treated Heps-bearing mice. The results revealed that the SCPP11 (oral administration) exhibited a significant enhanced effect of antitumor activity when combined with 5-Fu. Moreover, a increased effect was also observed in boosting immunity functions when the Heps-bearing mice receiving SCPP11 combination with 5-Fu administration, including increased in thymus indexes and enhancing serum IL-2 and TNF-α secretion. In addition, SCPP11 could ameliorate the hematological and biochemical parameters changes induced by 5-Fu to normal level, and reduce the formation of MDA and enhance the activities of SOD in liver to against 5-Fu induced free radical damage. The above results suggested that the SCPP11 combined with 5-Fu presented enhanced effects on antitumor activity and the SCPP11 could attenuate the 5-Fu-induced toxicity effect. It could serve as a new and promising adjuvant for chemotherapy drugs.

Morphine improved the antitumor effects on MCF-7 cells in combination with 5-Fluorouracil

BACKGROUND

The most frequently used opioid in cancer pain management is morphine which remains a cornerstone for the management of cancer pain, due to the largest experience existing among physicians and widely availability in a variety of formulation. Considering that analgesics on cancer pain is often under the condition of chemotherapy and 5-Fluorouracil (5-FU) is widely used today as a potent drug for the treatment of advanced cancers, whether analgesics such as morphine, interferes the chemotherapy such as 5-FU, arose as a considerable problem.

METHODS

In this study, the MCF-7 breast cancer cells were used to determine the antitumor effects of the 5-FU in combination with morphine. The cell proliferation was determined by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay and the apoptosis was determined by the Annexin V/PI staining and flow cytometry. The immunocytochemistry and western blot was used to determine the Bcl-2 and Bax expression.

RESULTS

It was shown that in MCF-7 cells, the proliferation was inhibited, the apoptosis was promoted, the Bcl-2 expression was suppressed and the Bax expression was promoted by both 5-FU alone and morphine alone, while the superior effects were achieved in combination with the two drugs.

CONCLUSION

These results suggest that the morphine may have the beneficial effects on the antitumor chemotherapy with 5-FU, in stead of interferential effects.

Nicotine increases survival in human colon cancer cells treated with chemotherapeutic drugs

Cigarette smoking is implicated in the development of colon cancer. Furthermore, nicotine increases cell proliferation and inhibits apoptosis through α7-nicotinic acetylcholine receptor (α7-nAChR) activation in human colon carcinoma cells. An open issue is whether nicotine interfere with colorectal cancer pharmacological treatment, by inhibiting drug-mediated apoptosis. To assess this hypothesis, we evaluated nicotine effect on Caco-2 and HCT-8 colon cancer cells, treated with 5-Fluorouracil (5-FU) and Camptothecin (CPT), chemotherapeutics commonly utilized as adjuvant treatment of colon cancer. Nicotine decreased anti-proliferative and pro-apoptotic effects exerted by chemotherapeutics on both cell lines. These effects partially reverted by exposure to α-bungarotoxin (α-BTX), an inhibitor of α7-nAChR. Nicotine addition to Caco-2 and HCT-8, treated with 5-FU or CPT, decreased the cleavage of substrate of caspase 3 and 7, poly-ADP-ribose polymerase (PARP). Moreover, P-ERK/ERK ratio was modified by nicotine addition to 5-FU and CPT treated cells in an opposite manner. However, when co-administrating PD98059, an ERK phosphorylation inhibitor, an increased apoptosis was observed. In Caco-2 and HCT-8 nicotine reverted 5-FU and CPT apoptotic effects through AKT phosphorylation, as demonstrated by apoptotic increase in presence of LY294002, an AKT phosphorylation inhibitor. Nicotine interfered with colorectal cancer pharmacological treatment in vitro by inhibiting apoptosis induced by chemotherapeutic drugs. Nicotine anti-apoptotic effects were exerted through ERK and AKT pathway activation.

Plasma microRNAs predicting clinical outcome in metastatic colorectal cancer patients receiving first-line oxaliplatin-based treatment

The conventional first-line chemotherapy for metastatic colorectal cancer (mCRC) consists of fluorouracil (5-FU) in combination with either oxaliplatin or irinotecan. We have explored microRNAs (miRNAs) in plasma as potential predictive markers to oxaliplatin-based chemotherapy. The expression of 742 miRNAs was examined in plasma samples from 24 mCRC patients (12 responders and 12 non-responders) before onset and after four cycles of 5-FU/oxaliplatin. The top differentially expressed miRNAs between responders and non-responders were selected for further analysis in a validation cohort of 150 patients. In the validation cohort, there was a significant overrepresentation of miRNAs with higher mean expression in the non-responder group than in the responder group before treatment (p < 0.002). Moreover, we found three miRNAs (miR-106a, miR-484, and miR-130b) to be significantly differentially expressed before treatment (p = 0.008, 0.008, and 0.008, respectively). All three miRNAs were upregulated in non-responders. High expression of miR-27b, miR-148a, and miR-326 were associated with decreased progression-free survival (Hazard ratios (HR) of 1.4 (95% CI 1.1-1.8, p = 0.004), 1.3 (95% CI 1.1-1.6, p = 0.007), and 1.4 (95% CI 1.1-1.8, p = 0.008), respectively). miR-326 was also associated with decreased overall survival (HR 1.5 (95% CI 1.1-2.0, p = 0.003)). There were no significantly differentially expressed miRNAs in association with clinical outcome after four cycles of chemotherapy. The present study demonstrates that plasma miRNAs analyzed before treatment may serve as non-invasive markers predicting outcome in mCRC patients treated with 5-FU and oxaliplatin-based chemotherapy.

Methods of overcoming treatment resistance in colorectal cancer

Metastatic colorectal cancer remains a lethal disease with a poor prognosis in the majority of patients. Multiple drug combinations have been developed in recent years that have significantly improved response rates and overall survival however resistance to these drugs is inevitable. Novel agents are currently being developed and participation in clinical trials should be encouraged. In the absence of other treatment options in a patient with good performance status, there is compelling evidence for re-challenging with previously administered agents in different combinations. The aim of this review is to discuss mechanisms of resistance and methods to overcome treatment resistance in patients with metastatic colorectal cancer who are refractory to 5-FU, irinotecan, oxaliplatin, cetuximab and bevacizumab therapy.

The monoclonal antibody CH12 augments 5-fluorouracil-induced growth suppression of hepatocellular carcinoma xenografts expressing epidermal growth factor receptor variant III

5-Fluorouracil (5-FU) is one of the most common chemotherapeutic agents used for the treatment of hepatocellular carcinoma (HCC). However, chemoresistance has precluded the use of 5-FU alone in clinical regimens. Combination therapies with 5-FU and other anticancer agents are considered to be a therapeutic option for patients with HCC. We previously reported that the expression of epidermal growth factor receptor variant III (EGFRvIII) can decrease the sensitivity of HCC cells to 5-FU. To overcome this problem, in this study, we elucidated the mechanism underlying EGFRvIII-mediated 5-FU resistance. We observed that EGFRvIII expression can induce miR-520d-3p downregulation and the ensuing upregulation of the transcription factor E2F-1 and the enzyme thymidylate synthase (TS), which may lead to drug resistance. Intriguingly, we found that CH12, a monoclonal antibody directed against EGFRvIII, and 5-FU together had an additive antitumor effect on EGFRvIII-positive HCC xenografts and significantly improved survival in all mice with established tumors when compared with either 5-FU or CH12 alone. Mechanistically, compared with 5-FU alone, the combination more noticeably downregulated EGFR phosphorylation and Akt phosphorylation as well as the expression of the apoptotic protector Bcl-xL and the cell cycle regulator cyclin D1. Additionally, the combination upregulated the expression of the cell cycle inhibitor p27 in in vivo treatment. More interestingly, CH12 treatment upregulated miR-520-3p and downregulated E2F-1 and TS at the mRNA and protein levels. Collectively, these observations suggest that the combination of 5-FU with mAb CH12 is a potential means of circumventing EGFRvIII-mediated 5-FU resistance in HCC.

Different chemotherapy effects of 5-FU given via different routes of administration

AIM: To determine the concentration of 5-fluorouracil (5-FU) in the portal vein blood and liver in a rabbit model after chemotherapy with 5-FU given via different routes of administration.

METHODS: The portal vein blood and liver biopsy were collected at different time points after intravenous chemotherapy, intraperitoneal chemotherapy or intraperitoneal sustained-releasing chemotherapy with 5-FU. The concentration of 5-FU was measured by HPLC. The area under the concentration-time curve (AUC) was calculated based on the concentration-time curve.

RESULTS: The concentration of 5-FU in the portal vein reached the peak (0.82 μg/mL) two hours after intraperitoneal administration of sustained-releasing agents. The concentration of 5-FU in the portal vein was stable and the drug could be detected until day 16 after treatment. In contrast, the average concentration of 5-FU in the portal vein of animals receiving intraperitoneal injection of 5-FU was 20.67 μg/mL 15 minutes after injection and the drug was undetectable 24 h later. 5-FU in the portal vein of animals receiving intravenous chemotherapy was undetectable 4 h later. AUC in the intravenous, intraperitoneal and sustained-releasing groups was 21.57 μg/(mL•h), 42.85 μg/(mL•h) and 70.08 μg/(mL•h), respectively. 5-FU in liver biopsy could be detected until day 12 after intraperitoneal administration of sustained-releasing agents. In contrast, 5-FU in liver biopsy was undetectable 24 h later in animals receiving intraperitoneal injection of 5-FU.

CONCLUSION: Intraperitoneal sustained-releasing chemotherapy may prolong the effective exposure time of 5-FU in the portal vein and enhance chemotherapeutic effects in the liver.

Combination of cisplatin/S-1 in the treatment of patients with advanced gastric or gastroesophageal adenocarcinoma: Results of noninferiority and safety analyses compared with cisplatin/5-fluorouracil in the First-Line Advanced Gastric Cancer Study

BACKGROUND

The aim of developing oral fluorouracil (5-FU) is to provide a more convenient administration route with similar efficacy and the best achievable tolerance. S-1, a novel oral fluoropyrimidine, was specifically designed to overcome the limitations of intravenous fluoropyrimidine therapies.

PATIENTS AND METHODS

A multicentre, randomised phase 3 trial was undertaken to compare S-1/cisplatin (CS) with infusional 5-FU/cisplatin (CF) in 1053 patients with untreated, advanced gastric/gastroesophageal adenocarcinoma. This report discusses a post-hoc noninferiority overall survival (OS) and safety analyses.

RESULTS

Results (1029 treated; CS = 521/CF = 508) revealed OS in CS (8.6 months) was statistically noninferior to CF (7.9 months) [hazard ratio (HR) = 0.92 (two-sided 95% confidence interval (CI), 0.80-1.05)] for any margin equal to or greater than 1.05. Statistically significant safety advantages for the CS arm were observed [G3/4 neutropenia (CS, 18.6%; CF, 40.0%), febrile neutropenia (CS, 1.7%; CF, 6.9%), G3/4 stomatitis (CS, 1.3%; CF, 13.6%), diarrhoea (all grades: CS, 29.2%; CF, 38.4%) and renal adverse events (all grades: CS, 18.8%; CF, 33.5%)]. Hand-foot syndrome, infrequently reported, was mainly grade 1/2 in both arms. Treatment-related deaths were significantly lower in the CS arm than the CF arm (2.5% and 4.9%, respectively; P<0.047).

CONCLUSION

CS is noninferior to CF with a better safety profile and provides a new treatment option for patients with advanced gastric carcinoma.

Don extract synergizes the antitumor effects of low dose 5-fluorouracil through induction of apoptosis and metabolism

Traditional Chinese medicines have been recognized as a new source of anticancer drugs or chemotherapy adjuvant to enhance the efficacy of chemotherapy and to ameliorate the side effects. This study aimed to investigate the antitumor effects of combined Scutellaria barbata D. Don extract (SBE) and 5-FU treatment in vitro and in vivo and the potential mechanisms. SBE was prepared and analyzed by HPLC. Tumor growth inhibition both in vitro and in vivo, cell apoptosis, apoptosis related protein expressions (P53, bid, bax, bcl-2), caspase-3 activities and 5-FU related enzymes were assessed. SBE could significantly synergize the antitumor effects of low dose 5-FU both in vivo and in vitro. SBE could increase the apoptosis inducing effect of low dose 5-FU in both Bel-7402 and HCT-8 cells. Also, caspase-3 activities, P53 and bax expressions were significantly increased, while bid and bcl-2 expressions were significantly decreased in drug combination groups, compared with individual drug treatment groups. Furthermore, SBE could significantly decrease the mRNA levels of dihydropyrimidine dehydrogenase. These results showed that combined treatment with SBE and low dose 5-FU can significantly inhibit the tumor growth both in vitro and in vivo, which might be related with apoptosis and regulations of 5-FU metabolism.

Bolus 5-fluorouracil as an alternative in patients with cardiotoxicity associated with infusion 5-fluorouracil and capecitabine: a case series

BACKGROUND

5-Fluorouracil (5-FU) is the backbone of chemotherapy regimens approved for treatment of colorectal cancer. The incidence of cardiotoxicity associated with 5-FU ranges from 1.5% to 18%; 48% as anginal symptoms and 2% as cardiogenic shock. Cardiotoxicity is unpredictable and no alternative chemotherapeutics have been defined so far.

PATIENTS AND METHODS

We present a case series of six patients who developed cardiotoxicity on infusional fluorouracil and/or capecitabine and were challenged with bolus 5-FU for the treatment of their malignancies. Four patients were tested for polymorphic abnormality of the human dihydropyrimidine dehydrogenase gene (DPYD) with the TheraGuide 5-FU™ (Myriad Genetic Laboratories, Inc., Salt Lake City, UT, USA) pharmacogenetic test.

RESULTS

Five patients were challenged with oral capecitabine that reproduced clinical and/or diagnostic concerns. All six patients tolerated bolus 5-FU either as a radiosensitizing agent or as chemotherapy without recurrence of a cardiac insult. DPYD was normal in the four patients tested.

CONCLUSION

Cardiotoxicity induced by 5-FU seems to be schedule-dependent. Bolus 5-FU can be used in patients developing cardiotoxicity due to 5-FU infusion or capecitabine with vigilance.

Therapeutic enhancement of S-1 with CPT-11 through down-regulation of thymidylate synthase in bladder cancer

Thymidylate synthase (TS), a target enzyme of 5-fluorouracil (5-FU), is significantly associated with prognosis in various cancers. Recently, it has been reported that S-1, a novel 5-FU-based agent has an effect on bladder cancer. However, in cells with high TS level, S-1 did not have significant effects. Therefore, we examined whether down-regulation of TS enhanced effects of S-1 in them. First, we measured TS level in an aggressive bladder cancer cell line, KU-19-19 by enzyme-linked immunosorbent assay (ELISA) and evaluated its sensitivity to 5-FU using a small interfering RNA (siRNA) for TS. Next, we measured TS mRNA after exposure to various agents. Finally, we evaluated enhancement of cytotoxicity of S-1 by CPT-11 (7-ethyl-10-[4-(1-piperidino)-1-piperidino]carbonyloxycamptothecin) which down-regulated TS in in vivo study. The median TS and dihydropyrimidine dehydrogenase (DPD) level was 53.3 ng/mg and 80.3 ng/mg in KU-19-19 cells, respectively. The 5-FU treatment in KU-19-19 cells transfected with siRNA for TS gene (TYMS) inhibited cell growth more significantly than that for nontargeting control. Down-regulation of TS was observed after exposure to SN-38 (7-ethyl-10-hydroxycamptothecin) in a dose-dependent manner. The combination treatment of 5-FU and SN-38 significantly inhibited cell growth, as compared to the single treatment. Meanwhile, in cells transfected with siRNA for TYMS, neither an additive nor a synergistic effect was observed. Also, combined S-1 and CPT-11 dramatically inhibited tumor growth, compared to S-1 or CPT-11 alone in in vivo study. In conclusion, CPT-11 down-regulated TS level and enhanced the effect of S-1. Thus, the combination therapy with S-1 and CPT-11 might be a novel modality for bladder cancer, even with high TS level.

This study confirmed that thymidylate synthase (TS) level in an aggressive human bladder cancer cell line, KU-19-19, was relatively higher than that in other cancer and presented that irinotecan (CPT-11) could down-regulate TS. Finally, the combination therapy with S-1 and CPT-11 resulted in significant tumor growth inhibition through down-regulation of TS in KU-19-19. Thus, combined S-1 and CPT-11 might be a novel treatment in bladder cancer, even with high TS.

Role of neoadjuvant therapy and adjuvant therapy in treatment of pancreatic cancer

Pancreatic cancer is a highly malignant tumor that has a low resection rate. In Western countries, pancreatic cancer is the fourth cause of death in malignant tumors. Combined therapy is particularly important for the treatment of pancreatic cancer. Preoperative neoadjuvant therapy and postoperative adjuvant therapy are important parts of combined treatment for pancreatic cancer. Adjuvant therapy can improve survival and quality of life of patients with pancreatic cancer, and neoadjuvant therapy can reduce the primary lesion and lymph node metastasis, provide patients with the possibility of surgery to improve radical resection, decrease intraoperative bleeding and postoperative complications, and improve postoperative survival and life quality of patients. This article reviews the role of adjuvant therapy and neoadjuvant therapy in the management of pancreatic cancer.

Establishing a model for assessing DNA damage in murine brain cells as a molecular marker of chemotherapy-associated cognitive impairment

AIMS

Chemotherapy-associated cognitive impairment often follows cancer chemotherapy. We explored chemotherapy-induced DNA damage in the brain cells of mice treated with 5-fluorouracil (5FU), an antineoplastic agent, to correlate the extent of DNA damage to behavioral functioning in an autoshaping-operant mouse model of chemotherapy-induced learning and memory deficits (Foley et al., 2008).

MAIN METHODS

Male, Swiss-Webster mice were injected once with saline or 75 mg/kg 5FU at 0, 12, and 24h and weighed every 24h. Twenty-four h after the last injection, the mice were tested in a two-day acquisition and the retention of a novel response task for food reinforcement. Murine brain cells were analyzed for the presence of single- and double-strand DNA breaks by the single cell gel electrophoresis assay (the Comet assay).

KEY FINDINGS

We detected significant differences (p<0.0001) for all DNA damage characteristics (DNA "comet" tail shape, migration pattern, tail moment and olive moments) between control mice cohort and 5FU-treated mice cohort: tail length - 119 vs. 153; tail moment - 101 vs. 136; olive moment - 60 vs. 82, correspondingly. We found a positive correlation between increased response rates (r=0.52, p<0.05) and increased rate of errors (r=0.51, p<0.05), and DNA damage on day 1. For all 15 mice (saline-treated and 5FU-treated mice), we found negative correlations between DNA damage and weight (r=-0.75, p<0.02).

SIGNIFICANCE

Our results indicate that chemotherapy-induced DNA damage changes the physiological status of the brain cells and may provide insights to the mechanisms for cognitive impairment after cancer chemotherapy.

Bcl-2 gene silence enhances the sensitivity toward 5-Fluorouracil in gastric adenocarcinoma cells. Biomed Pharmacother. 2013;67:615-619. [PMID: 23684481 DOI: 10.1016/j.biopha.2013.03.007]

Because of increased insensitivity or resistance to chemical treatment in tumor patients, specific apoptotic gene silence may provide a rational approach for the development of novel therapeutic strategies. This study was to investigate whether downregulation of Bcl-2 expression by small interfering RNA (siRNA) against the Bcl-2 gene would enhance the apoptosis and sensitivity of gastric adenocarcinoma SGC-7901 cell to 5-Fluorouracil. Transfections of SGC-7901 cells with siRNA were performed using cationic liposomes. Sequence-specific downregulation of Bcl-2 expression was measured by RT-PCR and Western blot analysis. Cell proliferation assay was determined by MTT assay and apoptotic cell rates were determined by flow cytometry assay. Results showed that the siRNA could downregulate Bcl-2 expression, which increased apoptosis and sensitivity of SGC-7901 cell to 5-Fluorouracil (P<0.05). This study indicated that inhibition of Bcl-2 expression by siRNA would be useful a new useful protocol to increase the effect of 5-Fluorouracil on treatment of gastric adenocarcinoma, which may play an important role in developing novel therapeutic strategies in the future.

Nano-engineering of 5-fluorouracil-loaded magnetoliposomes for combined hyperthermia and chemotherapy against colon cancer. Eur J Pharm Biopharm. 2013;85:329-338. [PMID: 23485475 DOI: 10.1016/j.ejpb.2013.01.028]

The present investigation aimed to develop magnetoliposome nanoparticles loaded with 5-fluorouracil by following a reproducible thin film hydration technique. The physicochemical characterization (including electron microscopy analysis, dynamic light scattering, infrared spectrometry, X-ray diffractometry, electrophoresis, and surface thermodynamics) suggested that superparamagnetic magnetite nuclei were successfully embedded into a multilamellar lipid vesicle. Magnetic responsiveness of these nanocomposites was quantitatively analyzed by determining the hysteresis cycle and qualitatively confirmed by microscopic visualizations. A high frequency alternating electromagnetic field was further used to define their heating properties. The absence of cytotoxicity in human colon fibroblast CCD-18 and in human colon carcinoma T-84 cell lines and excellent hemocompatibility of these core/shell particles were demonstrated. Additionally, 5-fluorouracil incorporation was investigated by two procedures: (i) entrapment into the nanoparticulate matrix and (ii) surface deposition onto already formed magnetoliposome particles. The former method reported greater drug loading values and a sustained release profile. Interestingly, 5-fluorouracil release was also triggered by the heating properties of the nanoparticles (hyperthermia-triggered drug release). Hence, we put forward that magnetoliposome particles hold important properties, that is, magnetically targeted delivery, hyperthermia inducing capability, high 5-fluorouracil loading capability, and hyperthermia-triggered burst drug release, suggestive of their potential for a combined antitumor therapy against colon cancer.

The IDEA (International Duration Evaluation of Adjuvant Chemotherapy) Collaboration: Prospective Combined Analysis of Phase III Trials Investigating Duration of Adjuvant Therapy with the FOLFOX (FOLFOX4 or Modified FOLFOX6) or XELOX (3 versus 6 months) Regimen for Patients with Stage III Colon Cancer: Trial Design and Current Status

The International Duration Evaluation of Adjuvant Chemotherapy (IDEA) collaboration was established to prospectively combine and analyze data from several randomized trials conducted around the world to answer whether a three-month course of oxaliplatin-based adjuvant therapy (FOLFOX4/modified FOLFOX6 or XELOX) is non-inferior to the current standard six-month treatment for patients with stage III colon cancer, with a primary endpoint of three years disease-free survival. The IDEA steering committee comprises two members from each group coordinating an individual trial and two members from a secretariat who coordinate combining of the data and management of the joint analysis. Members of the IDEA agreed to combine the data from their individual trials to enable definitive analysis consisting of at least 10,500 patients. With accrual of 8,797 patients at the end of February 2013, the IDEA is on track to achieve its accrual objective of at least 10,500 patients by the end of 2013.

A comparative study of mitomycin C and 5-Fluorouracil trabeculectomy in west Africa

PURPOSE

To report the comparative efficacy and safety of intraoperative 5-fluorouracil (5-FU) or mitomycin C (MMC) in primary trabeculectomy in Nigeria.

MATERIALS AND METHODS

Retrospective chart review of patients undergoing primary antimetabolite trabeculectomy in Lagos, Nigeria between 1996 and 2003. We included 129 patients (132 eyes) of the 210 patients with greater than one year postoperative follow-up. Success rates between groups were compared by Kaplan-Meier survival analysis. IOP changes between groups were compared with ANOVA test. Non-parametric comparisons were performed with the Chi-square test with Yates correction or Fisher exact test. A P value less than 0.05 was considered statistically significant.

RESULTS

Seventy-three eyes underwent 5-FU (5-FU group) and 59 eyes underwent MMC augmentation (MMC group) during primary trabeculectomy. The 5-FU group had longer mean follow-up of 53 ± 26 months than the MMC group (38 ± 18 months, P<0.001). The preoperative intraocular pressure was 25.4 ± 6.2 in the MMC group and 25.8 ± 6.0 mm Hg in the 5FU group (P=0.8). Postoperative IOPs were significantly lower (P<0.05) in the MMC group at all follow up visits except between 30-35 months (P=0.07). The probability of maintaining an IOP less than 19 mmHg and 15 mmHg without additional medication or needle revisions at 2 and 3 years postoperatively was 71 (95% CIs, 54-82%) and 64% (95% CIs, 53-76%) respectively for the 5FU group and 81 (95% CIs,71-92%) and 79% (95% CIs,69-90%) respectively for the MMC group. The MMC group had significantly better survival times, both for IOP less than 19 mm Hg (P=0.03) and IOP less than 15 mm Hg (P= 0.006). At last follow up, 40 eyes (30.3%) had lost more than 2 lines of Snellen visual acuity, 24 from 5-FU and 16 from the MMC group (P=0.8). The MMC group was statistically less likely than the 5-FU group to require medications (18.5% vs. 41.1%, P =0.007) or needle revisions (5.1% vs. 17.8%, P=0.03) to control IOP. Blebitis and endophthalmitis developed in one eye each in both groups. Persistent hypotony was observed in 4 eyes (6.8%) in the MMC group only.

CONCLUSIONS

In this study of Nigerian patients, intraoperative application of MMC was more efficacious than 5-FU in lowering IOP following primary trabeculectomy. However, delayed ocular hypotony was only seen with MMC use.

Management of stage II/III rectal cancer

Pelvic and distant recurrences in rectal cancer can be associated with substantial morbidity, and patients with stage II and III disease are at increased risk for both local and distant failure when compared to patients with earlier stage disease. Refinement of surgical techniques have helped to reduce the risk of recurrence, and adjuvant therapies such as radiation to the tumor and regional lymph nodes and 5-fluorouracil-based systemic therapies have helped to further provide local control and may have an impact on overall survival. Numerous studies have been completed internationally in an effort to determine the optimal treatment regimen for this patient population. The importance of pre-therapy staging is of key importance as sequencing of therapy appears to significantly impact outcome. In the United States, patients with stage II/III rectal cancer are recommended to undergo preoperative concurrent pelvic radiation and chemotherapy followed by surgery several weeks later in order to maximize treatment response, which is then followed by approximately 4 months of adjuvant 5-fluorouracil-based systemic therapy. In Europe, there is substantial evidence supporting the use of neoadjuvant radiation therapy, however the role of concurrent chemotherapy remains a question of debate. Regardless of definitive management strategy, close follow-up in the post-treatment setting is important for early tumor detection and for managing treatment-related side-effects.

Effect of 5-Fu on the ratio of SP cells and expression of HIF-2α and ABCG2 in human gastric cancer cell line SGC7901 under hypoxia

AIM: To investigate the mechanism of resistance to 5-fluorouracil (5-Fu) chemotherapy in gastric cancer cells under hypoxia.

METHODS: The proliferative activity of SGC7901 cells was determined by MTT assay, and the half maximal inhibitory concentration (IC₅₀) of 5-Fu under normoxia and hypoxia was calculated. After 5-Fu at a concentration of IC₅₀ was incubated with cells for 24, 48 or 72 h under hypoxia, the percentage of SP cells was detected by Hoechst 33342 staining, the expression of HIF-2α protein was detected by immunocytochemistry, and the expression of ABCG2 was detected by fluorescence immunocytochemistry.

RESULTS: 5-Fu inhibited the proliferation of SGC7901 cells in a dose- and time-dependent manner under normoxia and hypoxia. The IC₅₀ of 5-Fu under normoxia and hypoxia was 100 mg/L and 200 mg/L, respectively. The ratio of SP cells in SGC7901 cells was 1.87% under nomoxia, and significantly increased after induction by hypoxia for 24, 48, and 72 h. Treatment with 5-Fu had no significant impact on the proportion of SP cells under normoxia, but gradually increased SP cell proportion under hypoxia. The expression levels of HIF-2α and ABCG2 proteins in SGC7901 cells were lower under normoxia. Treatment with 5-Fu had no significant impact on the expression of HIF-2α and ABCG2 proteins under normoxia, but gradually increased their expression under hypoxia.

CONCLUSION: The mechanism underlying the resistance of SGC7901 cells to 5-Fu under hypoxia may be related to inducing HIF-2α and ABCG2 expression and promoting stemness.

Acute Reversible Heart Failure Caused by Coronary Vasoconstriction due to Continuous 5-Fluorouracil Combination Chemotherapy

We present the case of a 51-year-old male patient who received adjuvant chemotherapy consisting of oxaliplatin, bolus and continuous 5-fluorouracil (5-FU) and leucovorin after anterior resection because of locally advanced rectal cancer. Preoperative chemotherapy with capecitabine (an oral 5-FU prodrug) had been well tolerated. Two days after initiation of the first course of chemotherapy, the patient reported typical chest pain. The ECG showed ST elevations and prominent T waves in almost all leads. Due to suspicion of a high-risk acute coronary syndrome, an urgent cardiac catheterization was performed. It showed a generally reduced coronary flow with multiple significant stenoses (including the ostia of the left and right coronary artery), as well as a highly reduced left ventricular function with diffuse hypokinesia. Due to the meanwhile completely stable situation of the patient after medical acute coronary syndrome treatment, no ad hoc intervention was performed to allow further discussion of the optimal management. Thereafter, the patient remained clinically asymptomatic, without any rise in cardiac necrosis parameters; only NT-pro-BNP was significantly elevated. A control cardiac catheterization 2 days later revealed a restored normal coronary artery flow with only coronary calcifications without significant stenoses, as well as a normal left ventricular ejection fraction. Cardiovascular symptoms occurred on the second day of continuous 5-FU treatment. As cardiotoxic effects seem to appear more frequently under continuous application of 5-FU, compared to the earlier established 5-FU bolus regimens, treating medical oncologists should pay special attention to occurring cardiac symptoms and immediately interrupt 5-FU chemotherapy and start a cardiologic work-up.

Hexahydrocurcumin enhances inhibitory effect of 5-fluorouracil on HT-29 human colon cancer cells

AIM: To investigate the ability of hexahydrocurcumin (HHC) to enhance 5-fluorouracil (5-FU) in inhibiting the growth of HT-29 cells by focusing on cyclooxygenase (COX)-2 expression.

METHODS: Antiproliferative effects of HHC and 5-FU, alone and in combination, on growth of HT-29 human colon cancer cells were assessed using 5-diphenyltetrazolium bromide (MTT) reduction assay. In combination treatment, low doses of 5-FU were used combined with various concentrations of HHC to minimize the toxicity and side effects of 5-FU. The therapeutic effects of these drugs on down-regulation of COX-2 mRNA and protein expression were examined using semi-quantitative reverse transcription–polymerase chain reaction (RT-PCR) and Western blotting analysis.

RESULTS: MTT reduction assay indicated that HHC alone markedly decreased the viability of HT-29 human colon cancer cells compared to control. Semi-quantitative RT-PCR analysis indicated that HHC is a selective COX-2 inhibitor. This finding was supported by the observation that HHC significantly down-regulates COX-2 mRNA expression compared to the control (control: 100.05% ± 0.03% vs HHC: 61.01% ± 0.35%, P < 0.05) but does not alter COX-1 mRNA. In combined treatment, addition of HHC to a low dose of 5-FU exerts a synergistic effect against the growth of HT-29 cells by markedly reducing cell viability to a greater degree than monotherapy. Semi-quantitative RT-PCR indicated that 5-FU at the concentration of 5 μmol/L in combination with HHC at the concentration of 25 μmol/L significantly down-regulates COX-2 mRNA expression when compared with values in cells treated with 5-FU or HHC alone (HHC + 5-FU: 31.93% ± 5.69%, 5-FU: 100.66% ± 4.52% vs HHC: 61.01% ± 0.35%, P < 0.05).

CONCLUSION: HHC together with 5-FU exerts a synergistic effect and may prove chemotherapeutically useful in treating human colon cancer.

5-Fluorouracil-induced coronary thrombosis: A case report and review of the literature

5-Fluorouracil (5-FU) is a key component in the treatment of many gastrointestinal tract adenocarcinomas. Despite its proven therapeutic efficacy, this chemotherapeutic agent also possesses several associated cardiac toxicities, including coronary vasospasm and coronary thrombosis. We report a case of acute coronary syndrome with thrombotic subtotal coronary artery occlusion in the setting of home 5-FU infusion highlighting the importance of careful pre-administration cardiac evaluation and close monitoring during drug administration.

Efficacy and safety of metronomic chemotherapy for patients with advanced primary hepatocellular carcinoma with major portal vein tumor thrombosis

Background/Aims

Low-dose metronomic chemotherapy involves the frequent administration of comparatively low doses of cytotoxic agents with no extended breaks, and it may be as efficient as and less toxic than the conventional maximum tolerated dose therapy. This study evaluated the feasibility and therapeutic efficacy of metronomic chemotherapy in patients with advanced hepatocellular carcinoma (HCC) with major portal vein thrombosis (PVT).

Methods

Thirty consecutive HCC patients with major PVT with or without extrahepatic metastasis were prospectively allocated to metronomic chemotherapy consisting of epirubicin being infused through the correct hepatic artery at a dose of 30 mg/body surface area (BSA) every 4 weeks, and cisplatin (15 mg/BSA) and 5-fluorouracil (50 mg/BSA) every week for 3 weeks, with intervening 1 week breaks. The treatment response was assessed using response evaluation criteria in solid tumors (RECIST).

Results

In total, 116 cycles of metronomic chemotherapy were administered to the 30 patients, with a median of 3 cycles given to individual patients (range, 1-15 cycles). Six patients (20.0%) achieved a partial response and six patients (20.0%) had stable disease. The median time to disease progression and overall survival were 63 days (range, 26-631 days) and 162 days (95% confidence interval; range, 62-262 days), respectively. Overall survival was significantly associated with baseline alpha-fetoprotein level (P=0.001) and tumor response (P=0.005). The baseline alpha-fetoprotein level was significantly associated with the disease control rate (P=0.007). Adverse events were tolerable and managed successfully with conservative treatment.

Conclusions

Metronomic chemotherapy may be a safe and useful palliative treatment in HCC patients with major PVT.

Regulation of colon cancer recurrence and development of therapeutic strategies

Recurrence of colon cancer still remains a major issue which affects nearly 50% of patients treated by conventional therapeutics. Although the underlying causative factor(s) is not fully understood, development of drug-resistance has been associated with induction of cancer stem or stem-like cells (CSCs) which constitute a small sub-population of tumor cells known to be highly resistant to chemotherapy. In fact, the discovery of CSCs in a variety of tumors (including colon cancer) has changed the view of carcinogenesis and therapeutic strategies. Emerging reports have indicated that to improve patient outcomes, conventional anticancer therapies should be replaced with specific approaches targeting CSCs. Thus, therapeutic strategies that specifically target CSCs are being sought to reduce the risk of relapse and metastasis. In order to specifically target colon CSCs (while sparing somatic intestinal stem cells), it is critical to identify unique deregulated pathways responsible for self-renewal of CSCs and colon cancer recurrence. Colon CSCs present a unique opportunity to better understand the biology of solid tumors. Thus, a better understanding of the clinical signs and symptoms of colon cancer patients (undergoing surgery or chemotherapy) during perioperative periods, along with the underlying regulatory events affecting the stem/progenitor cell self-renewal and differentiation of colon epithelial cells, is of immense importance. In this review we discuss the implication of clinical factors and the emerging role of CSCs during recurrence of colon cancer along with the development of new therapeutic strategies involving the use of natural agents.

Primary sebaceous gland carcinoma of the bulbar conjunctiva without involvement of eyelid: A clinical dilemma

Sebaceous gland carcinoma usually arises from the meibomian or Zeis glands within the eyelid, but tumor arising primarily from the conjunctiva, especially bulbar conjunctiva, is a rarity. We hereby report a case of a 50-year-old female who presented with a painless mass in the inferior limbus, encroaching the cornea and hanging over the lower eyelid without involving it. Imprint cytology was suggestive of adenosquamous carcinoma. Management consisted of wide local excision, cryotherapy to tumor bed, and topical 5-fluorouracil (5-FU) 1% preoperatively and postoperatively. Histopathologic analysis was in favor of sebaceous gland carcinoma. This case suggests that although sebaceous gland carcinoma commonly originates as a lid tumor, it can present as a bulbar conjunctival mass. Topical 5-FU is a viable and efficient cost-effective alternative for neo-adjuvant and adjuvant treatment of sebaceous gland carcinoma.

Up-regulation of cyclooxygenase-2-derived prostaglandin E(2) in colon cancer cells resistant to 5-fluorouracil

PURPOSE

It has been suggested that constitutive up-regulation of cyclooxygenase (COX)-2 is associated with resistance to apoptosis, increased angiogenesis, and increased tumor invasiveness in various cancers including colon cancer. There are many factors involved in the resistance to 5-fluorouracil (5-FU) in colon cancer. However, little is known about the role of COX-2 in acquired resistance to 5-FU in colon cancer.

METHODS

Hence we investigated whether COX-2 contribute to acquired resistance to 5-FU in colon cancer cells, using cytotoxicity assay for cell survival, reverse transcription-polymerase chain reaction (RT-PCR) for vascular endothelial growth factor (VEGF), quantitative RT-PCR for COX-1 and COX-2, and enzyme-linked immunosorbent assay for PGE(2).

RESULTS

The 5-FU resistant colon cancer cells, SNU-C5/5FUR, showed increased expression of COX-2, prostaglandin E(2) (PGE(2)), and VEGF, compared to its parental cell (SNU-C5). By treatment with meloxicam, the expression of PGE(2) and VEGF was reduced significantly in the resistant cells, but not in the parent cells.

CONCLUSION

These results demonstrate that COX-2 derived PGE(2) is up-regulated and COX-2 inhibitor may have an anti-angiogenic effect in the colon cancer cells resistant to 5-FU.

Capecitabine-induced cardiotoxicity: case report and review of the literature

Capecitabine, an oral prodrug of 5-fluorouracil (5fu), has been integrated into the management of multiple cancer types because of convenience of administration and efficacy comparable with 5fu. Cardiotoxicity induced by 5fu—in particular angina—has been well described in the literature, but reports of adverse cardiac events with capecitabine are also emerging. The mechanism underlying 5fu cardiotoxicity has long been thought to result from coronary vasospasm, but animal-model studies and patient echocardiographic findings both suggest a cardiomyopathic picture. Although 5fu cardiotoxicity is often reversible and can be managed supportively, presentations that are more severe—including arrhythmias, acute ischemic events, and cardiogenic shock—have been documented. In this report, we describe the case of a patient who ultimately required a pacemaker after developing symptomatic bradycardia and sinus arrest while receiving capecitabine for colon cancer.

A Stability-Indicating RP-HPLC Assay Method for 5-Fluorouracil

The present study describes the development of a validated RP-HPLC method for the determination of 5-fluorouracil in presence of its degradation products or other pharmaceutical excipients. Stress studies were performed on 5-fluorouracil and it was found that it degrades sufficiently in alkaline conditions, while negligible degradation was observed in acidic, neutral, oxidative and photolytic conditions. The peaks of the degradation products were not observed in the chromatogram due to the nonchromophoric nature of the degradation moiety formed. The separations were carried out on a C-18 reversed phase column (Phenomenex; Prodigy ODS3V, 250x4.6 mm, 5 mu) using 50mM KH(2)PO(4) (pH, 5.0) as mobile phase at a flow rate of 1.2 ml/min and temperature of 30 degrees . The wavelength of detection was 254 nm. A retention time of nearly 6 minutes was obtained. Analytical validation parameters such as specificity and selectivity, linearity, accuracy and precision were evaluated. The calibration curve for 5-fluorouracil was linear (r(2)=0.999+/-0.0005) from range of 10 mug/ml to 100 mug/ml. Relative standard deviation values for all the key parameters, was less than 2.0 %. The recovery of the drug after standard addition to the degraded sample was found to be 104.69%. Thus, the developed RP-HPLC method was found to be suitable for the determination of 5-fluorouracil in bulk as well as stability samples of the pharmaceutical dosage forms containing various excipients.

Topical treatment options for conjunctival neoplasms

Topical therapies offer a nonsurgical method for treating conjunctival tumors by delivering high drug concentrations to the ocular surface. Over the past ten years, topical agents have been used by investigators to treat various premalignant and malignant lesions of the conjunctiva, such as primary acquired melanosis with atypia, conjunctival melanoma, squamous intraepithelial neoplasia and squamous cell carcinoma of the conjunctiva, and pagetoid spread of the conjunctiva arising from sebaceous cell carcinoma. Despite the enthusiasm generated by the success of these agents, there are unanswered questions regarding the clinical efficacy of this new nonsurgical approach, and whether a single topical agent can achieve cure rates comparable with traditional therapies. Furthermore, the long-term consequences of prolonged courses of topical chemotherapeutic drugs on the ocular surface are unknown, and the ideal regimen for each of these agents is still being refined. In this review, we present specific guidelines for treating both melanocytic and squamous neoplasms of the conjunctiva, utilizing the available data in the literature as well as our own clinical experience at the Memorial Sloan-Kettering Cancer Center.

Topical Mitomycin-C versus Subconjunctival 5-Fluorouracil for Management of Bleb Failure

PURPOSE

To compare the efficacy and safety of topical mitomycin-C (MMC) drops with that of subconjunctival 5-fluorouracil (5-FU) injections for management of early bleb failure after trabeculectomy or combined phacoemulsification and trabeculectomy with posterior chamber intraocular lens implantation (PT+PCIOL).

METHODS

In a randomized comparative study, 37 eyes of 37 patients with impending early bleb failure received MMC 0.02% eye drops for 2 or 4 weeks (19 eyes) or subconjunctival 5-FU injections, 5 mg per dose (18 eyes). Complete success was defined as 5 < IOP ≤ 18 mmHg without medications.

RESULTS

Baseline characteristics were comparable between the study groups. However, there were more cases of combined PT+PCIOL in the MMC group [11 (57.9%) eyes versus 3 (16.7%) eyes, P = 0.017]. Mean preoperative IOP was 20.5±8.85 mmHg in the MMC group and 25.82±11.35 mmHg in the 5-FU group (P = 0.129), which was decreased to 13.2±6.1 and 10.6±4.8 mmHg respectively after 12 months (P = 0.159). There was no significant difference between the study groups in terms of bleb extent (P = 0.170), height (P = 0.178) or vascularity (P = 0.366). At the end of the study, complete success was achieved in 13 eyes (68.4%) in the MMC group and 14 eyes (77.8%) in the 5-FU group (P = 0.714). The survival of success at 8 months (median follow-up) was 89.5% and 86.5% in the MMC and 5-FU groups respectively; the number of glaucoma medications (P = 0.707) and best-corrected visual acuity (P = 0.550) were also comparable. Complication rates were similar in the study groups (P = 0.140).

CONCLUSION

Topical MMC 0.02% has comparable safety and efficacy to subconjunctival 5-FU injections for management of early bleb failure. Topical MMC 0.02% drops are more convenient and can be initiated first, while 5-FU injections may be reserved for eyes with an insufficient response to topical MMC.

A Phase II Study of Docetaxel, Cisplatin and 5- Fluorouracil (TPF) In Patients with Locally Advanced Head and Neck Carcinomas

BACKGROUND

The combination of cisplatin and 5-fluorouracil (PF) is currently considered a standard and effective regimen for the treatment of advanced head and neck carcinomas. The aim of this study was to evaluate the efficacy and safety of docetaxel, cisplatin and 5-fluorouracil (TPF) in patients with unresectable head and neck carcinomas.

METHODS

Forty-six patients with previously untreated non-metastatic stage IV head and neck carcinomas were enrolled. All patients received three cycles of induction chemotherapy with docetaxel (75 mg/m(2)), cisplatin (40 mg/m(2)) (days 1-2), and 5-FU (500 mg/m(2), days 1-3), repeated every 21 days. Following induction chemotherapy, all patients underwent concurrent chemoradiotherapy using weekly cisplatin (30 mg/m(2)) and a median total dose of 70 Gy was delivered. Clinical response rate and toxicity were the primary and secondary end-points of the study.

RESULTS

There were 31 men and 15 women. All patients had non-metastatic stage IV (T2-3N2-3 or T4N0-3) of disease. Overall and complete response rates were 74% and 24% respectively. Advanced T4 classification was associated with poorer response rate (p value=0.042). The major (grade 3-4) treatment-related toxicities were myelosuppression (78%), anorexia (13%), diarrhea (7%), emesis (11%) and stomatitis/pharyngitis (24%).

CONCLUSION

In comparison with the data of historical published trials of the PF regimen, the TPF regimen was more effective. However, the TPF regimen appears to be associated with a higher incidence of major toxicities. Therefore, our limited findings support the TPF regimen as an alternative chemotherapeutic regimen for advanced head and neck carcinomas.

EGCG enhances 5-fluorouracil-induced cell growth inhibition in human hepatocellular carcinoma cell line BEL-7402

AIM: To investigate whether epigallocatechin-3-gallate (EGCG) enhances 5-fluorouracil (5-FU)-induced cell growth inhibition in human hepatocellular carcinoma cell line BEL-7402 and to explore potential mechanisms involved.

METHODS: MTT assay was used to evaluate cell viability. Western blotting analysis was performed to detect protein expression, and small interfering RNA was used to suppress COX-2 expression. ELISA assay was applied to test the release of prostaglandin E2 (PGE2).

RESULTS: Treatment with different concentrations of EGCG (5, 10, 25, or 50 mmol/L) significantly inhibited the growth of BEL-7402 cells compared with control cells (treated with 0.1% DMSO, all P < 0.05). When cells were treated with 10 mmol/L 5-FU in combination with either 5, 10, 25, or 50 mmol/L EGCG, the percentages of viable cell significantly decreased when compared with cells treated with each drug alone, suggesting a synergistic effect between the two drugs. Moreover, EGCG down-regulated the expression of COX-2 and reduced the release of PGE2 in BEL-7402 cells.

CONCLUSION: EGCG enhances 5-FU-induced cell growth inhibition in human hepatocellular carcinoma cell line BEL-7402 possibly by down-regulating COX-2 expression and inhibiting PGE2 release.

Minute liver metastases from a rectal carcinoid: A case report and review

We here report a 43-year-old male patient with minute liver metastases from a rectal carcinoid. Hepatic nodules were diagnosed during surgery, although they were not diagnosed by preoperative computed tomography or ultrasound examination. The rectal carcinoid was resected together with liver metastases and the patient has had no disease recurrence for 5 years following postoperative treatment of hepatic arterial infusion chemotherapy (HAIC) using 5-fluorouracil (5-FU) and oral administration of 1-hexylcarbamoyl-5-fluorouracil (HCFU). In 2003, a health check examination indicated presence of occult blood in his stool. Barium enema study revealed a rectal tumor in the lower rectum and colonoscopy showed a yellowish lesion with a size of 30 mm in diameter. Pathological examination of the biopsy specimen indicated that the rectal tumor was carcinoid. Although preoperative imaging examinations failed to detect liver metastases, 2 min nodules were found on the surface of liver during surgery. A rapid pathological examination revealed that they were metastatic tumors from the rectal carcinoid. Low anterior resection was performed for the rectal tumor and the pathological report indicated that there were 4 metastatic lymph nodes in the rectal mesentery. The patient received treatment by HAIC using 5-FU plus oral administration of HCFU and survived for 5 years.

We also review world-wide current treatments and their efficacy for hepatic metastases of carcinoid tumors.

Effects of paeonol and 5-FU on the proliferation and apoptosis of human esophageal carcinoma EC9706 cells

AIM: To investigate the effects of paeonol alone or in combination with 5-fluorouracil (5-FU) on the proliferation and apoptosis of human esophageal carcinoma EC9706 cells.

METHODS: Six different concentrations of paeonol (7.81, 15.63, 31.25, 62.50, 125.00 and 250.00 mg/L, respectively), three different concentrations of 5-FU (12.50, 25.00 and 50.00 mg/L, respectively), and paeonol (31.25 mg/L) in combination with 5-FU (12.50 mg/L) were used to treat EC9706 cells for different durations (24, 48 and 72 h). Untreated EC9706 cells were used as the control group. The proliferation of EC9706 cells was detected by methyl thiazolyl tetrazolium (MTT) assay after treatment for different durations. After treatment of EC9706 cells with paeonol at concentrations of 31.25, 62.50, 125.00 and 250.00 mg/L for 72 hours, the cell cycle was analyzed by flow cytometry; cell morphological changes were observed using an inverted microscope; the morphology of apoptotic cells was observed by HE staining and light microscopy. The expression of apoptosis-associated proteins Bcl-2 and Bax was detected by immunocytochemistry after treatment of EC9706 cells with paeonol (31.25 mg/L) and 5-FU (12.50 mg/L), alone or in combination, for 48 hours.

RESULTS: Paeonol or 5-FU could significantly inhibit the proliferation of EC9706 cells in a concentration- and time-dependent manner (both P < 0.05). Paeonol in combination with 5-FU showed more significant inhibitory effects on the proliferation of EC9706 cells when compared with paeonol or 5-FU alone (both P < 0.05). Paeonol (125.00 mg/L) treatment altered the cell cycle distribution of EC9706 cells: the percentages of cells in G₀/G₁ and G₂/M phases decreased, while that of cells in S phase increased (G₀/G₁ phase: 21.18% ± 2.28% vs 62.17% ± 5.23%; G₂/M phase: 0.76% ± 0.54% vs 9.92% ± 3.10%; S phase 78.06% ± 2.82% vs 27.91% ± 2.13%; all P < 0.05). Typical apoptotic changes were observed in EC9706 cells treated with paeonol. Both paeonol and 5-FU down-regulated the expression of Bcl-2 and up-regulated the expression of Bax, which was especially prominent in the combination group (2.21 ± 0.14 vs 5.67 ± 0.30 and 4.22 ± 0.34; 8.55 ± 0.33 vs 3.90 ± 0.27 and 6.28 ± 0.26, all P < 0.05).

CONCLUSION: Paeonol can significantly inhibit the proliferation and induce the apoptosis of human esophageal carcinoma EC9706 cells. Paeonol in combination with 5-FU shows a synergistic effect in suppressing the proliferation and promoting the apoptosis of EC9706 cells.

Effects of combined Tan IIA and 5-FU on cell proliferation, apoptosis, and the expression of HIF-1α and mutant P53 in human gastric cancer cell line SGC7901 under hypoxia

AIM: To investigate the effects of combined tanshinone IIA (Tan IIA) and 5-fluorouracil (5-FU) on cell proliferation, apoptosis, and the expressions of hypoxia-inducible factor-1 alpha (HIF-1α) and mutant P53 (mt P53) in human gastric cancer cell line SGC7901 under hypoxia.

METHODS: Hypoxia was induced in SGC7901 cells by cobalt dichloride treatment. SGC7901 cells under hypoxia were treated with different concentrations of Tan IIA in combination with 10.0 mg/L of 5-FU for 24, 48 and 72 hours. Cell proliferation was detected by methyl thiazolyl tetrazolium (MTT) assay. Cell apoptosis was detected by Hoechst staining. The expression of HIF-1α and mt P53 proteins was detected by immunocytochemistry.

RESULTS: Combined Tan IIA and 5-FU significantly inhibited the proliferation of SGC7901 cells (all P < 0.01) in a dose- and time-dependent manner under hypoxia. The reduced proliferation rate of cells incubated with Tan IIA at a concentration of 10 mg/L and 5-FU for 72 hours was 67.46%. Hoechst staining showed that Tan IIA in combination with 5-FU promoted the apoptosis of SGC7901 cells in a dose- and time-dependent manner under hypoxia (all P < 0.01). Immunocytochemical staining revealed that the expression levels of HIF-1α and mt P53 proteins in SGC7901 cells under hypoxia were evidently higher than those in SGC7901 cells under normal conditions (t = 22.786 and 13.914, respectively; both P < 0.01). However, Tan IIA in combination with 5-FU significantly downregulated the expression of HIF-1α and mt P53 proteins in SGC7901 cells under hypoxia (F = 182.234 and 130.062, respectively; both P < 0.01). A significant positive correlation was noted between the expression of HIF-1α and mt P53 in SGC7901 cells (n = 5, r = 0.995, P < 0.01).

CONCLUSION: Tan IIA can significantly enhance 5-FU-mediated growth inhibition and apoptosis induction in SGC7901 cells under hypoxia perhaps by downregulating HIF-1α and mt P53 protein expression.

Sirolimus, bevacizumab, 5-Fluorouracil and irinotecan for advanced colorectal cancer: A pilot study

AIM: To evaluate the efficacy and the safety of combined 5-Fluorouracil, irinotecan, bevacizumab and sirolimus in refractory advanced colorectal carcinoma.

METHODS: We initiated a regimen with at day 1 an injection (iv) of bevacizumab at 5 mg/kg, followed by 180 mg/m² irinotecan, followed by Leucovorin 400 mg/m², followed by a 5-Fluorouracil bolus 400 mg/m² and a 46-h infusion 2400 mg/m². Sirolimus was given orally as continuous administration of 2 mg twice a day every days. This treatment was repeated every 14 d.

RESULTS: A total of 12 patients were enrolled. All patients presented with metastatic disease that had failed at least three lines of chemotherapy that contained oxaliplatin, irinotecan and bevacizumab. Cetuximab failure was also observed in all K-Ras wild-type patients. The median number of cycles was 8.5 (range 2-20) and clinical benefit was observed in eight patients. The median time to progression was 5 mo and the median survival was 8 mo. Grade 3 neutropenia developed in four patients, and grade 3 diarrhea and stomatitis in two.

CONCLUSION: The combination regimen of 5-Fluorouracil, irinotecan, bevacizumab and sirolimus in advanced colorectal carcinoma after failure of classical treatment is feasible and promising. Further evaluation of this combination is required.

Effect of 5-FU on modulation of disarrangement of immune-associated cytokines in experimental acute pancreatitis

AIM: To investigate the effects of 5-Fluorouracil (5-FU) on modulation of pro-inflammatory and anti-inflammatory cytokines in acute pancreatitis and the mechanism of it in the treatment of acute pancreatitis.

METHODS: Male Sprague Dawley rats were assigned to 3 Groups: Group A, sham operated rats as controls (n = 7); Group B, acute pancreatitis induced by ductal injection with 5% sodium cholate at a volume of 1.0 mL/kg without any other treatment; Group C, after the pancreatitis was induced as in Group B, the rats were injected intravenously with 5-FU 40 mg/kg. The animals in Groups B and C were killed at 2, 6 and 24 h after operation (n = 7), and blood samples were taken for measurement of tumor necrosis factor-α (TNF-α), interleukin-1 (IL-1), interleukin-6 (IL-6) (by bioassay), and interleukin-10 (IL-10), transforming growth factor-β (TGF-β) (by ELISA). The wet weight of pancreatic tissue, serum amylase levels and white blood cells were also measured.

RESULTS: Four rats in Group B and one in Group C died after pancreatitis was induced. Both pro-inflammatory cytokines (TNF-α, IL-1, IL-6) at the 2 and 6 h period and the anti-inflammatory cytokines (IL-10, TGF-β) at 24 h increased significantly (P < 0.05) in rats of Group B. After treatment with 5-FU, TNF-α, IL-1, and IL-6 in serum of rats of Group C were inhibited at 2 and 6 h after operation (P < 0.05), and IL-10, TGF-β were inhibited at 24 h compared to Group B (P < 0.05). Obvious improvements in the severity of the acute pancreatitis, including the amylase levels, wet weight of pancreatic tissue and neutrophil counts, were also observed after treatment with 5-FU.

CONCLUSION: 5-FU is an anti-metabolic and immunosuppressive agent which can minimize the abnormal immune cytokine response and relieve the pathophysiological disorders associated with experimental acute pancreatitis.

Drug selection in isolated hepatic perfusion for nonresectable liver tumors: recent trends and perspectives

Isolated hepatic perfusion (IHP) involves a method of complete vascular isolation of the liver to take the advantage of directed intensive chemotherapy that has minimal systemic toxicity. Recent clinical studies mainly employed melphalan with or without tumor necrosis factor alpha (TNF-α), or with hyperthermia in IHP. The results of these studies showed that higher response rates and survival rates could be achieved by IHP than by traditional therapeutics for non-resectable liver tumors. In this article, we discussed the current status, recent developments and future perspectives of drug selection in IHP.

Preparation of chitosan-polyaspartic acid-5-fluorouracil nanoparticles and its anti-carcinoma effect on tumor growth in nude mice

AIM: To prepare chitosan-polyaspartic acid-5-fluorouracil (CTS-Pasp-5Fu) nanoparticles and investigate its anti-carcinoma effect and toxicity.

METHODS: CTS-Pasp-5Fu nanoparticles were synthesized by ionic gelatification. Male BABL/c nude mice were injected with SGC-7901 gastric carcinoma cell line mass to establish a human gastric carcinoma model. They were randomly allocated into 4 groups: CTS-Pasp-5Fu (containing 5-Fu 1.25 mg/kg), 5-Fu (1.25 mg/kg), CTS-Pasp and normal saline groups. Tumor weight was measured and assay of colony forming unit-granulocyte and macrophage (CFU-GM) was performed. The structural change of cells and tissues was observed and the Bax and Bcl-2 genes were detected.

RESULTS: Compared with normal saline, the inhibition rates of tumor growth for the CTS-Pasp, 5-Fu and CTS-Pasp-5Fu groups were 5.58%, 58.69% and 70.82%, respectively. The tumor inhibition rates for the CTS-Pasp, 5-Fu and CTS-Pasp-5Fu groups were 5.09%, 65.3% and 72.79%, respectively. There was a significant decrease in the number of CFU-GM formation and increase of total bilirubin, and alanine aminotransferase in the 5-Fu group, but no change in those of the other three groups. There was no change in white blood cell count and creatinine among the four groups. Pathological section of liver and nephridial tissues showed that the damage in the 5-Fu group was more severe than that in the CTS-Pasp-5Fu group. 5-Fu and CTS-Pasp-5Fu groups could both down-regulate the Bcl-2 expression and up-regulate the Bax expression to different extent, and the accommodate effect of CTS-Pasp-5Fu was more obvious than 5-Fu.

CONCLUSION: The tumor inhibition rate of CTS-Pasp-5Fu nanoparticles is much higher than that of 5-Fu alone.

Effects of endogenous nitric oxide induced by 5-fluorouracil and L-Arg on liver carcinoma in nude mice

AIM: To study the effects of endogeous nitric oxide induced by 5-fluorouracil (5-FU) and L-arginine (L-Arg) on the human liver carcinoma model in nude mice.

METHODS: The human liver carcinoma model in nude mice was established with BEL-7402 cells and normal saline (NS), 5-FU and 5-FU + L-Arg injected intraperitoneally. The tumor size was measured. The necrotic degree and range were observed under microscope. The apoptosis of cancer cell was detected by turmina deoxynucleotidyl transferanse mediated dUTP nick end labeling (TUNEL) method. Immunohistochemical method was performed to determine the expression of iNOS, P16, BAX. The chemical colorimetry was used to test the activity and nitrate reductase method was adopted to test the concentration of nitric oxide (NO) in the tumor tissue. The BI2000 pathological image analyzer was used to analyze the result of immunohistochemistry.

RESULTS: 5-FU combined with L-Arg could inhibit the tumor growth apparently. In NS, 5-FU and 5-FU+L-Arg groups, the changes of tumor volumes were 257.978 ± 59.0, 172.232 ± 66.0 and 91.523 ± 26.7 mm³, respectively (P < 0.05 5-FU vs 5-FU + L-Arg group; P < 0.05 NS vs 5-FU + L-Arg group; P < 0.05, NS vs 5-FU group). The necrotic range and apoptosis index were significantly increased after the drug injection. The necrotic range was biggest in 5-FU + L-Arg group (χ² = 15.963, P < 0.05).

The apoptosis indexes were as follows: NS, 17.4% ± 6.19%; 5-FU, 31.3% ± 12.3%; and 5-FU + L-Arg, 46% ± 15.24% (P < 0.05, 5-FU vs 5-FU + L-Arg; P < 0.05, NS vs 5-FU + L-Arg; P < 0.05, NS vs 5-FU). The expression and activity of iNOS were increased in the tumor tissue. The concentration of NO was also increased. F of optical density of iNOS, iNOS activity and NO concentration are 31.693, 21.949, and 33.909, respectively, P < 0.05. The concentration of NO was related to the expression of P16 and BAX. The correlation coefficient was 0.764 and 0.554.

CONCLUSION: 5-FU combined with L-Arg can inhibit the growth of tumor in nude mice. The effect may be related to inducing the synthesis and increasing the activity of iNOS. The production of NO is increased, and it can enhance the expression of apoptosis-related gene and antioncogene.

Hypoestoxide inhibits tumor growth in the mouse CT26 colon tumor model

AIM: To evaluate the effect of the natural diterpenoid, hypoestoxide (HE) on the growth of established colon cancer in mice.

METHODS: The CT26.WT mouse colon carcinoma cell line was grown and expanded in vitro. Following the expansion, BALB/c mice were inoculated s.c. with viable tumor cells. After the tumors had established and developed to about 80-90 mm³, the mice were started on chemotherapy by oral administration of HE, 5-fluorouracil (5-FU) or combination.

RESULTS: The antiangiogenic HE has previously been shown to inhibit the growth of melanoma in the B16F₁ tumor model in C57BL/6 mice. Our results demonstrate that mean volume of tumors in mice treated with oral HE as a single agent or in combination with 5-FU, were significantly smaller (> 60%) than those in vehicle control mice (471.2 mm³vs 1542.8 mm³, P < 0.01). The significant reductions in tumor burden resulted in pronounced mean survival times (MST) and increased life spans (ILS) in the treated mice.

CONCLUSION: These results indicate that HE is an effective chemotherapeutic agent for colorectal cancer in mice and that HE may be used alone or in combination with 5-FU.