The present and future of combination chemotherapy in bladder cancer

Enhancing photodynamyc therapy efficacy by combination therapy: dated, current and oncoming strategies

Combination therapy is a common practice in many medical disciplines. It is defined as the use of more than one drug to treat the same disease. Sometimes this expression describes the simultaneous use of therapeutic approaches that target different cellular/molecular pathways, increasing the chances of killing the diseased cell. This short review is concerned with therapeutic combinations in which PDT (Photodynamyc Therapy) is the core therapeutic partner. Besides the description of the principal methods used to assess the efficacy attained by combinations in respect to monotherapy, this review describes experimental results in which PDT was combined with conventional drugs in different experimental conditions. This inventory is far from exhaustive, as the number of photosensitizers used in combination with different drugs is very large. Reports cited in this work have been selected because considered representative. The combinations we have reviewed include the association of PDT with anti-oxidants, chemotherapeutics, drugs targeting topoisomerases I and II, antimetabolites and others. Some paragraphs are dedicated to PDT and immuno-modulation, others to associations of PDT with angiogenesis inhibitors, receptor inhibitors, radiotherapy and more. Finally, a look is dedicated to combinations involving the use of natural compounds and, as new entries, drugs that act as proteasome inhibitors.

Investigating the cytotoxic and apoptosis inducing effects of monoterpenoid stylosin in vitro

The aim of this study was to investigate the cytotoxic and anticancer activities of stylosin, a monoterpene extracted from an edible plant, Ferula ovina, on 5637 and HFF3 cells using MTT and comet assays and DAPI staining. To assess stylosin effects, cells were cultured in the presence of various concentrations of stylosin during three days; the IC(50) of stylosin on cancerous 5637 cells was less than its value on HFF3 normal cells, indicating that it might have anticancer properties. Investigating the mechanism of stylosin action revealed that it quickly induced DNA lesions and increased the number of apoptotic cells.

Diimine platinum(II) and palladium(II) complexes of dithiocarbamate derivative as potential antitumor agents: synthesis, characterization, cytotoxicity, and detail dna-binding studies

The synthesis and chemical characterization of two structurally related platinum(II) and palladium(II) complexes, [M(2,2'-bipyridine)(morpholinedithiocarbamate)]NO(3) or [M(bpy)(mor-dtc)]NO(3), where M = Pt(II) or Pd(II), are described. Studies of anti-tumor activities of these complexes against human cell tumor lines (K(562)) have been carried out. They show 50% cytotoxic concentration (Cc(50)) values much lower than that of cisplatin. Both of these water soluble complexes have been shown to interact with calf thymus DNA (ct-DNA) using difference absorption-, fluorescence-, and circular dichroism-titration techniques. These studies showed that both complexes exhibit cooperative binding and presumably intercalate in DNA. These complexes unexpectedly denature DNA at very low concentrations (50-100 microM). Several binding and thermodynamic parameters are also described.

Vinflunine in the treatment of bladder cancer

Vinflunine (VFL) is a third-generation bifluorinated semi-synthetic vinca alkaloid obtained by superacidic chemistry from its parent compound, vinorelbine. As with the other vinca alkaloids, the main antineoplastic effects of VFL arise from its interaction with tubulin, the major component of microtubules in mitotic spindles. In contrast to other vinca alkaloids, VFL shows some distinctive properties in terms of tubulin binding, possibly explaining its superior antitumor activity in vitro and in vivo compared with vinorelbine as well as its excellent safety profile. In transitional cell carcinoma (TCC), two single-agent phase II trials were performed testing VFL in platinum-pretreated patients, showing moderate response rates and promising disease control rates. Therefore, the first phase III trial in modern times for second-line TCC of the urothelium was designed in order to further investigate the activity of VFL. First results were presented at the 2008 ASCO conference. VFL appears to be a possible treatment option for patients with TCC progressing after first-line platinum-containing chemotherapy.

Methotrexate, vinblastine, doxorubicin and cisplatin combination regimen as salvage chemotherapy for patients with advanced or metastatic transitional cell carcinoma after failure of gemcitabine and cisplatin chemotherapy

We investigated the safety and efficacy of a methotrexate, vinblastine, doxorubicin and cisplatin (M-VAC) combination regimen as second-line chemotherapy for patients with advanced or metastatic transitional cell carcinoma who failed first-line gemcitabine and cisplatin (GC) chemotherapy. Thirty patients who had progressed or relapsed after GC chemotherapy as first-line treatment were enrolled in this study. The major toxicities were neutropaenia and thrombocytopaenia. A grade 3 or 4 neutropaenia occurred in 19 (63.3%) and a grade 3 or 4 thrombocytopaenia developed in nine patients (30.0%). There were no life-threatening complications during the study. The overall response was 30%. A complete response was achieved in two patients (6.7%) and a partial response in seven (23.3%). The overall disease control rate was 50%. Seven out of 16 patients who had responded previously to GC responded to M-VAC, while 2 out of 14 who had not responded to GC responded to M-VAC. The median response duration was 3.9 months and the median progression-free survival was 5.3 months. The median overall survival was 10.9 months. M-VAC showed encouraging efficacy and reversible toxicities in patients who had progressed after GC chemotherapy and, especially, M-VAC appears to be a reasonable option as a sequential treatment regimen in patients who responded previously to GC chemotherapy.

Preparation and characterization of N-succinyl-N′-octyl chitosan micelles as doxorubicin carriers for effective anti-tumor activity

N-Succinyl-N'-octyl chitosan (SOC) was prepared and characterized by elemental analysis, FTIR, (1)H NMR, WAXD and TG. An anticancer drug, doxorubicin (DOX), was incorporated into polymeric micelles forming by SOC in aqueous solutions. Critical micelle concentrations (CMC) of SOC were determined by fluorescence spectroscopy. The DOX-loaded SOC micelles were characterized by measurement of size and drug loading. The loading content of DOX increased with increasing drug-to-carrier ratio, and the more amount of the octyl chain, the higher the drug loading content. The average size, which was affected by the amount of octyl chain and drug loading content, was in the range of 100-200 nm. The polymeric micelles containing doxorubicin in the core region exhibited a sustained release and more cytotoxic activity against HepG2, A549, BGC and K562 than doxorubicin alone, this can be attributed to an endocytosis mechanism rather than passive diffusion.

Paclitaxel with cisplatin as salvage treatment for patients with previously treated advanced transitional cell carcinoma of the urothelial tract

BACKGROUND

This study was performed to evaluate the safety and efficacy of paclitaxel with cisplatin as salvage therapy in patients previously treated with gemcitabine and cisplatin (G/C) for advanced transitional cell carcinoma (TCC) of the urothelial tract.

METHODS

Twenty-eight patients with metastatic or locally advanced TCC who had received prior G/C chemotherapy were enrolled. All patients received paclitaxel (175 mg/m(2)) and cisplatin (60 mg/m(2)) every 3 weeks for eight cycles or until disease progression.

RESULTS

The median age was 61 years (range, 43-83 years), and the median Eastern Cooperative Oncology Group performance status was 1 (range, 0-2). The overall response rate was 36% [95% confidence interval (95% CI) = 18-54], with three complete responses and seven partial responses. The median time to progression was 6.2 months (95% CI = 3.9-8.5), and the median overall survival was 10.3 months (95% CI = 6.1-14.1). The most common Grade 3/4 nonhematologic and hematologic toxicities were emesis (10 of 28 patients; 36%) and neutropenia (5 of 110 cycles; 5%).

CONCLUSIONS

Salvage chemotherapy with paclitaxel and cisplatin displayed promising results with tolerable toxicity profiles in patients with metastatic or locally advanced TCC who had been pretreated with G/C.

Sequential gemcitabine and cisplatin followed by docetaxel as first-line treatment of advanced urothelial carcinoma: a multicenter phase II study of the Hellenic Oncology Research Group

BACKGROUND

The purpose of this study was to investigate the toxicity and efficacy of the sequential administration of gemcitabine (GMB) in combination with cisplatin (CDDP) followed by docetaxel (Taxotere) as first-line treatment of advanced urothelial carcinoma.

PATIENTS AND METHODS

Patients [aged </=70 years and performance status (PS) (Eastern Cooperative Oncology Group) 0-2] with previously untreated locally advanced/recurrent or metastatic urothelial carcinoma were eligible. Study treatment consisted of GMB (1000 mg/m(2), days 1 and 8) and CDDP (70 mg/m(2), day 1) (GP regimen), every 21 days for a total of four cycles followed by docetaxel (D; 100 mg/m(2), day 1) every 21 days for four cycles.

RESULTS

Thirty-eight patients with a median age of 67 years were enrolled; 67% of them had PS 0 and 87% stage IV disease. Patients received a median of four GP and four D cycles per patient. Grade 3-4 neutropenia occurred in 27% and 63% patients with GP and D, respectively. Grade 3-4 thrombocytopenia occurred in 11% of patients, only with the GP regimen. Other toxic effects were mild. There was no toxic death. The objective response rate was 55.2% [95% CI: 39.45%-71.07%]. Five patients had complete response (13.15%) and 16 patients had partial response (42.1%), while nine patients had disease stabilization (23.7%) (intention-to-treat analysis). After a median follow-up period of 13 months (range 1.5-40.5 months), the median time to progression was 6.8 months (range 1-40.5 months), the median overall survival 13 months (range 1.5-40.5 months), and the 1-year survival rate 55.3%.

CONCLUSION

The sequential administration of GP followed by D is active and well tolerated as first-line treatment of advanced urothelial carcinoma and merits to be further evaluated.

A phase II study of vinflunine in bladder cancer patients progressing after first-line platinum-containing regimen

A multicentre phase II trial to determine the efficacy of vinflunine as second-line therapy in patients with advanced transitional cell carcinoma (TCC) of the bladder; secondary objectives were to assess duration of response, progression-free survival (PFS) and overall survival (OS), and to evaluate the toxicity associated with this treatment. Patients had tumours that failed or progressed after first-line platinum-containing regimens for advanced or metastatic disease, or had progressive disease after platinum-containing chemotherapy given with adjuvant or neoadjuvant intent. Response and adverse events were assessed according to WHO criteria and NCI-CTC (version 2), respectively. Out of 51 patients treated with 320 mg m(-2) of vinflunine, nine patients responded to the therapy yielding an overall response rate of 18% (95% CI: 8.4-30.9%), and 67% (95%CI: 52.1-79.3%) achieved disease control (PR+SD). Of note, responses were seen in patients with relatively poor prognostic factors such as a short (<12 months) interval from prior platinum therapy (19%, including an 11% response rate in those progressing <3 months after platinum treatment), prior treatment for metastatic disease (24%), prior treatment with vinca alkaloids (14%) and visceral involvement (20%). The median duration of response was 9.1 months (95% CI: 4.2-15.0) and the median PFS was 3.0 months (95% CI: 2.4-3.8). The median OS was 6.6 months (95% CI: 4.8-7.6). The main haematological toxicity was grade 3-4 neutropenia, observed in 67% of patients (42% of cycles). Febrile neutropenia was observed in five patients (10%) and among them two were fatal. Constipation was frequently observed (but was manageable and noncumulative) and was grade 3-4 in only 8% of patients. The incidence of grade 3 nausea and vomiting was very low (4 and 6% of patients, respectively). Neither grade 3-4 sensory neuropathy nor severe venous irritation was observed. Moreover, and of importance in this particular study population, no grade 3-4 renal function impairment was observed. Vinflunine is an active agent for the treatment of platinum-pretreated bladder cancer, and these results warrant further investigation in phase III trials, either as monotherapy or in combination with other agents as treatment of advanced/metastatic TCC of the bladder.

Micelle delivery of doxorubicin increases cytotoxicity to prostate carcinoma cells

The use of doxorubicin as a chemotherapeutic agent is hindered by its toxic side effects on the normal cells of the body. The objective of this study was to determine if micelle-delivered doxorubicin could increase the effectiveness of doxorubicin against prostate carcinoma cells. Rat prostate carcinoma cells (MatLu) were cultured under standard conditions. Phosphate-buffered saline (PBS), doxorubicin and/or micelle solution (Pluronic 10500 solution) was added to the cell suspensions and incubated for 3 h. After incubation, cells were washed twice. Analysis consisted of: 1) immediate cell count and 2) proliferation assay at 24 and 144 h. After 24 h, samples with micelle-incorporated doxorubicin had 75% (10% pluronic with 10 microg/ml doxorubicin) and 80% (1% pluronic with 10 microg/ml doxorubicin) cell proliferation results compared with the control group. After 144-h incubation, these same two groups demonstrated cell proliferation results of only 30 and 43% of the control group. The in vitro cytotoxicity of doxorubicin against prostate carcinoma cells was dramatically increased by incorporating the molecule with polymeric micelles.

Combined chemotherapeutic and photodynamic treatment on human bladder cells by hematoporphyrin–platinum(II) conjugates

Four porphyrin-platinum complexes, conceived as a new approach in cancer therapy by combining the cytostatic activity of cisplatin or oxaliplatin and the photodynamic effect of hematoporphyrin in the same molecule, were studied in detail with respect to solubility and stability in cell culture medium as well as in terms of cytotoxicity and phototoxicity against J82 bladder cancer cells and UROtsa, normal urothelial cells. This study demonstrated that the most active and promising compound among the porphyrin-platinum conjugates investigated was the water-soluble porphyrin-platinum complex 4 (diammine[7,12-bis[1-(polyethyleneglycol-750-monomethylether-1-yl)ethyl]-3,8,13,17-tetramethylporphyrin-2,18-dipropionato]platinum(II)) which exhibited a synergistic antiproliferative effect compared to cisplatin and hematoporphyrin alone or a combination of the drugs.