gamma-linolenic-acid and Urinary-Bladder-Neoplasms

Gamma-linolenic acid (GLA) is known to be cytotoxic to malignant cells. We assessed the efficacy of the novel intravesical formulation, meglumine gamma-linolenic acid (MeGLA), in a phase II trial, in patients with recurrent, superficial bladder cancer.. Thirty patients with recurrent, superficial transitional cell carcinoma (TCC) were recruited. The tumour pattern was recorded at flexible cystoscopy. Patients received a single intravesical instillation of 50ml of either 50mg (1mg/ml) (15 patients), or 125mg (2.5mg/ml) (15 patients) of MeGLA in water, retained for one hour. At subsequent cystoscopy, the tumour patterns were recorded, prior to undertaking routine cystodiathermy. Biopsies were obtained for histological assessment. Responses were divided into complete, partial or none.. All 30 patients retained the drug for 1 hour without significant local or systemic side effects. There were 4 (13%) complete responses, 9 (30%) partial responses, and 17 (57%) non-responders. Histology showed no evidence of damage to surrounding urothelium.. Our data confirms the safety and tolerability of MeGLA, which is consistent with findings from a previous phase I trial. A response rate of 43% also indicates that MeGLA has a significant cytotoxic effect against TCC and the results are similar to those obtained using standard, single-dose, intravesical regimens.

Topics: Administration, Intravesical; Adult; Carcinoma, Transitional Cell; Drug Combinations; Female; gamma-Linolenic Acid; Humans; Male; Meglumine; Treatment Outcome; Urinary Bladder Neoplasms

Anthracyclines have been established as first-line drugs for intravesical use in the treatment of patients with superficial bladder carcinoma, although they result only in a modest reduction in tumor recurrence rates. The essential fatty acid gamma-linolenic acid (GLA) also is an effective cytotoxic agent against superficial bladder carcinoma when it is applied topically. The objective of this study was to assess the efficacy of combined epirubicin and GLA with the purpose of developing a suitable model for modification of existing intravesical regimens.. The human urothelial carcinoma cell lines MGH-U1 and RT112 were used in standard cytotoxicity assays and were exposed to meglumine GLA (MeGLA) and epirubicin in two-dimensional concentration matrices. A thiozolyl blue (methyl-thiazoldiphenyl tetrazolium) assay was used to determine residual cell biomass. Drug interaction was quantified by median-effect analysis software (CalcuSyn), and the evaluation of drug uptake utilized fluorescence confocal microscopy (FCM) and flow cytometry.. MeGLA caused a significant enhancement of anthracycline uptake, viewed by FCM, from 92 fluorescence units to 222 fluorescence units (P < 0.001). Flow cytometry confirmed the increased drug uptake and showed that the mean epirubicin content per cell increased from 23 to 57 units and from 8 to 24 units for MGH-U1 and RT112 cells, respectively (99% confidence interval < 0.3). This resulted in improved cytotoxicity, and it was shown that the drugs acted synergistically with all but the highest MeGLA concentrations.. The efficacy of epirubicin was enhanced significantly when it was used in combination with most concentrations of MeGLA (< 300 microg/mL), and the two agents acted synergistically. There was a corresponding increase in epirubicin uptake by cells under these conditions. At high MeGLA concentrations, however, anthracycline solubility was compromised, and drug synergy was lost.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Transitional Cell; Cell Division; Drug Synergism; Epirubicin; Flow Cytometry; gamma-Linolenic Acid; Humans; Meglumine; Microscopy, Confocal; Tumor Cells, Cultured; Urinary Bladder Neoplasms

The objective of this research was to assess the effects of the novel intravesical drug MeGLA in a physiologically representative model of superficial bladder cancer. Petri dishes were used to culture 5 mm square explants of rat bladder in minimal volumes of supplemented culture medium. Parental and resistant MGH-U1 urothelial cancer cells were transfected with a green fluorescent protein (GFP) vector. Transfectants were purified by flow cytometry. Cells were seeded onto the prepared organ cultures and imaging was performed using confocal microscopy. Confirmation of the tumour colonies was done using scanning electron microscopy. MeGLA was added at various concentrations to the colonies and its effects noted over several days. Results showed that colonies of GFP-MGH-U1 cells established themselves on the explants and could be identified by confocal microscopy. The colonies could then be followed over several days. The colonies were able to survive high concentrations of the drug of up to 1 mg/ml, 400 times the IC > 90% for monolayers and equivalent to doses in clinical use. We conclude that MeGLA is less effective in this system than on monolayer cell lines. However, it showed cytotoxic effects which were comparable to those seen with conventional agents in the same system.

Topics: Animals; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; gamma-Linolenic Acid; Humans; Meglumine; Neoplasms, Experimental; Organ Culture Techniques; Rats; Rats, Wistar; Urinary Bladder Neoplasms

This study investigated the effect on drug uptake in multidrug resistant cells by the incorporation of the essential fatty acid gamma-linolenic acid (GLA). The cell lines used were the MCF-7/R resistant human breast cancer and MGH-U1/R bladder cancer. Uptake of drug (doxorubicin, epirubicin, mitoxantrone and idarubicin) after the incorporation of GLA was investigated quantitatively by flow cytometry and qualitatively by confocal microscopy. There was no observable overall increase in drug uptake due to GLA incorporation into the cells as shown by flow cytometry. However, an increase in uptake of the chemotherapeutic agent idarubicin was observed in GLA-treated resistant cells compared with untreated cells using the confocal microscope. This overall increase in cellular drug uptake was not accompanied by a change in cellular drug distribution. Only one drug, mitoxantrone, displayed a change in intracellular drug distribution due to GLA incorporation into MCF-7/R cells. This suggests that essential fatty acid incorporation into the cellular membranes of some resistant cells may cause a shift in the intracellular distribution of certain chemotherapeutic drugs.

Topics: Anthracyclines; Breast Neoplasms; Drug Resistance, Multiple; Drug Resistance, Neoplasm; Female; Flow Cytometry; gamma-Linolenic Acid; Humans; Tumor Cells, Cultured; Urinary Bladder Neoplasms

The essential fatty acid gamma-linolenic acid (GLA) is an effective cytotoxic agent when applied topically and for prolonged periods to tumour cells. Topical application, by intravesical therapy, is firmly established in the treatment of superficial bladder cancer. However, this form of therapy is limited to a maximum duration of 2 h. At such a short drug exposure time, does GLA retain its cytotoxicity? We have examined this question by exposing the superficial bladder cancer cell lines MGH-U1 and RT112 to meglumine-GLA (MeGLA) for time intervals ranging from 30 min to 2 h, at drug concentrations ranging from 1000 to 1.95 microg/ml. The MTT viable biomass assay was used to assess cell kill. Greater than 90% inhibition was observed at a concentration of 125 microg/ml (IC > 90), at 2 h drug exposure. At shorter drug exposure times, higher drug concentrations were needed to induce the same effect. At 1 h drug exposure, the IC > 90 was recorded at 500 microg/ml. In vivo intravesical tolerance studies were conducted in rats. Rats exposed to 2.5 mg/ml MeGLA intravesically for 2 h or less remained well and bladder histology showed minimal changes. This study confirms that GLA retains its cytotoxicity at short drug exposure times and is well tolerated by normal bladder mucosa in vivo. Bladder mucosa tolerated > 10x the concentration required for the IC > 90 in vitro. MeGLA is therefore a feasible intravesical agent for superficial bladder cancer.

Topics: Administration, Intravesical; Animals; Cell Survival; Female; gamma-Linolenic Acid; Humans; Rats; Rats, Inbred F344; Time Factors; Tumor Cells, Cultured; Urinary Bladder Neoplasms

To compare the tumoricidal efficacy of meglumine gamma-linolenic acid (MeGLA), mitomycin C, epirubicin and water on two urothelial cell lines, and to establish the effect of serum protein levels derived from bladder cancer resection craters on the action of these agents.. The human urothelial cell lines MGHU-1 and RT112 and their drug-resistant variants were exposed to short pulses of aqueous MeGLA, mitomycin, epirubicin and water. Both adherent and suspended cells were exposed to these agents. The MTT viable biomass assay and a clonogenic assay were used to establish tumoricidal efficacy. These experiments were then repeated to assess the effect of added serum proteins on the test results. Estimates of protein in the waste irrigation fluid from 10 patients undergoing transurethral resection of bladder tumour (TURBT) were used to select the quantity of protein used in the study, to establish the clinical relevance.. MeGLA caused > 95% reduction in the residual viable biomass of adherent cells, compared with < 50% reduction with any other agent. Both epirubicin and mitomycin were as effective as MeGLA in preventing colony formation from suspended drug-sensitive (parental) cells. However, using multidrug-resistant (MDR) cell lines, only MeGLA prevented any colony formation, although counts were greatly reduced by mitomycin and epirubicin. Water was least effective as a tumoricidal agent on both adherent and suspended cells. On the latter, water was markedly inactivated by adding 5% serum. TURBT waste irrigation fluid was found frequently to contain such quantities of serous fluid contamination, as shown by albumin estimates in waste fluid from 10 consecutive patients undergoing this procedure.. MeGLA is an effective tumoricidal agent against both parental and MDR cell lines. Its efficacy is maintained in the presence of clinically relevant serum contamination.

Topics: Antibiotics, Antineoplastic; Carcinoma, Transitional Cell; Cell Adhesion; Drug Resistance, Neoplasm; Epirubicin; gamma-Linolenic Acid; Humans; Mitomycin; Neoplasm Recurrence, Local; Neoplasm Seeding; Serum Albumin; Tumor Cells, Cultured; Tumor Stem Cell Assay; Urinary Bladder Neoplasms; Water

Topics: Administration, Intravesical; gamma-Linolenic Acid; Humans; Urinary Bladder Neoplasms

To assess the cytotoxicity of Meglumine gamma linolenic acid (MeGLA) in serum-free application on 2 urothelial cancer cell lines, to examine whether the instant kill action of MeGLA is retained in a serum free environment, and to study the pharmacokinetics of intravesical instillation of gamma linolenic acid (GLA).. The 2 human urothelial cancer cell lines (MGH-U1 & RT112) were utilized in classical cytotoxicity assays in which drug exposure lasted 2 hours in serum or in serum-free application. The thiozolyl blue (MTT) assay was used to quantify the residual viable biomass 5 days later. Immediate cytotoxicity was also compared in serum and serum-free application. Four Wistar rats were used to study the intravesical absorption profile of tritiated GLA (3H-GLA).. There was a 10-fold enhancement of the lytic efficacy of MeGLA in serum-free application and this enhancement was also observed in experiments assessing instant kill. There was a similar enhancement of efficacy seen in the multi-drug resistant (MDR) clone of cells. The absorption profile showed < 2% of instilled counts were absorbed and the commonest destination for the absorbed GLA was the liver.. The cytotoxic action of MeGLA was enhanced in serum free application. This enhancement was maintained when cells expressed the MDR phenotype. There was limited absorption from the bladder. MeGLA is a feasible intravesical agent for use in superficial bladder cancer.

Topics: Administration, Intravesical; Animals; Carcinoma, Transitional Cell; Coloring Agents; Culture Media, Serum-Free; Drug Screening Assays, Antitumor; gamma-Linolenic Acid; Humans; Rats; Rats, Wistar; Tetrazolium Salts; Thiazoles; Tumor Cells, Cultured; Urinary Bladder Neoplasms