Effects of Taxotere and taxol on in vitro colony formation of freshly explanted human tumor cells

Natural compounds as lactate dehydrogenase inhibitors: potential therapeutics for lactate dehydrogenase inhibitors-related diseases

Lactate dehydrogenase (LDH) is a crucial enzyme involved in energy metabolism and present in various cells throughout the body. Its diverse physiological functions encompass glycolysis, and its abnormal activity is associated with numerous diseases. Targeting LDH has emerged as a vital approach in drug discovery, leading to the identification of LDH inhibitors among natural compounds, such as polyphenols, alkaloids, and terpenoids. These compounds demonstrate therapeutic potential against LDH-related diseases, including anti-cancer effects. However, challenges concerning limited bioavailability, poor solubility, and potential toxicity must be addressed. Combining natural compounds with LDH inhibitors has led to promising outcomes in preclinical studies. This review highlights the promise of natural compounds as LDH inhibitors for treating cancer, cardiovascular, and neurodegenerative diseases.

Do Steroids Matter? A Retrospective Review of Premedication for Taxane Chemotherapy and Hypersensitivity Reactions

PURPOSE

Despite the widespread use of the taxanes paclitaxel and docetaxel for a variety of cancers and their well-known association with hypersensitivity reactions (HSRs), there is still significant variation in the prescribing practices of steroids for premedication. Premedication almost always includes dexamethasone, which can be associated with multiple adverse effects if taken for extended periods of time. This study reviews the pattern of steroid premedication in patients who received paclitaxel or docetaxel at Stanford Cancer Institute between January 2010 and June 2020.

METHODS

We used an electronic query of the electronic medical record followed up with a manual review of patient charts to ask whether we could find a correlation between steroid premedication dosing and the incidence or severity of HSRs with the first taxane dose. Variables considered included steroid dose and route, dose and type of taxane, clinical cancer group, sex, and race.

RESULTS

Five thousand two hundred seventeen patients were identified as having received paclitaxel or docetaxel, and 3,181 met criteria for our analysis. There were 264 (8.3%) HSRs. In adjusted multivariate analysis, we found no correlation of HSR rate or severity among any of the variables evaluated except gynecology oncology clinic patients, who had an increased risk (hazard ratio [HR] 1.34) of HSRs overall and high-grade HSRs (HR 2.34), and female patients, who had a higher rate of HSRs overall (HR 1.26), but not high-grade HSRs.

CONCLUSION

Neither dexamethasone dose nor route correlated with subsequent HSRs. Given the potential for adverse events from repeated high-dose steroids, our findings suggest that routine use of lower doses, such as a single 10 mg dose of dexamethasone, as premedication for taxanes to prevent HSRs is preferable to the current prescribing guidelines.

Targeting Strategies for Enhancing Paclitaxel Specificity in Chemotherapy

Paclitaxel (PTX) has been used for cancer treatment for decades and has become one of the most successful chemotherapeutics in the clinic and financially. However, serious problems with its use still exist, owing to its poor solubility and non-selective toxicity. With respect to these issues, recent advances have addressed the water solubility and tumor specificity related to PTX application. Many measures have been proposed to remedy these limitations by enhancing tumor recognition via ligand-receptor-mediated targeting as well as other associated strategies. In this review, we investigated various kinds of ligands that have emerged as PTX tumor-targeting tools. In particular, this article highlights small molecule-, protein-, and aptamer-functionalized conjugates and nanoparticles (NPs), providing a promising approach for PTX-based individualized treatment prospects.

Targeting Strategies for Enhancing Paclitaxel Specificity in Chemotherapy

Paclitaxel (PTX) has been used for cancer treatment for decades and has become one of the most successful chemotherapeutics in the clinic and financially. However, serious problems with its use still exist, owing to its poor solubility and non-selective toxicity. With respect to these issues, recent advances have addressed the water solubility and tumor specificity related to PTX application. Many measures have been proposed to remedy these limitations by enhancing tumor recognition via ligand-receptor-mediated targeting as well as other associated strategies. In this review, we investigated various kinds of ligands that have emerged as PTX tumor-targeting tools. In particular, this article highlights small molecule-, protein-, and aptamer-functionalized conjugates and nanoparticles (NPs), providing a promising approach for PTX-based individualized treatment prospects.

Dexamethasone induces docetaxel and cisplatin resistance partially through up-regulating Krüppel-like factor 5 in triple-negative breast cancer

PURPOSE

Dexamethasone (Dex), a glucocorticoid (GC), is used as a pretreatment drug in cancer patients undergoing chemotherapy. Dex functions by binding to the glucocorticoid receptor (GR) to prevent allergic reactions and severe chemotherapeutic side effects such as nausea and vomiting. However, the mechanisms by which Dex causes chemoresistance remain unknown.

METHODS

We used docetaxel and cisplatin to treat triple-negative breast cancer (TNBC) cells with or without Dex and assessed cell proliferation using a sulforhodamine B colorimetric (SRB) assay. Additionally, Western blotting was employed to measure Krüppel-like factor 5 (KLF5), GR and several apoptosis-related proteins. To determine how the GR regulates KLF5, we used qRT-PCR, luciferase reporter assays and ChIP assays. Finally, we detected the involvement of Dex in TNBC chemotherapeutic resistance using HCC1806 xenograft model in vivo.

RESULTS

In this study, we demonstrated that Dex induces docetaxel and cisplatin resistance in TNBC cells in vitro and in vivo. Dex up-regulates pro-survival transcription factor KLF5 expression at both mRNA and protein levels dependent on GR. Importantly, Dex failed to promote cancer cell survival and tumor growth when KLF5 induction was blocked.

CONCLUSIONS

We conclude that KLF5 is a Dex-induced gene that contributes to Dex-mediated drug chemoresistance, providing a potential novel target for TNBC treatment.

Review : Pharmacokinetics and pharmacodynamics of the taxanes

Objectives. To review the pharmacokinetics and pharmacodynamics of docetaxel and paclitaxel.

Data Sources. We reviewed the literature through a MEDLINE search from 1982 to 1996. The terms docetaxel, paclitaxel, taxanes, and taxoids were used in the search. Relevant articles cited in literature obtained by MEDLINE searching, as well as new articles published in early 1997 in specific oncology journals, were also considered.

Data Extraction. We have reviewed the current literature with regard to the chemistry, mechanisms of action and pharmacology, pharmacokinetics, clini cal use, adverse effects, drug interactions, formula tion, dosage, administration, and pharmaceutical is sues of the taxanes.

Conclusion. Both docetaxel and paclitaxel are novel antineoplastic agents with significant activity in many types of cancer. The pharmacokinetics of both agents are best characterized by a three-compartment disposition profile. However, the pharmacokinetics of paclitaxel, not docetaxel, are non-linear and can be described by a saturation process in distribution and elimination. The nonlinearity appears to be associated more frequently with shorter infusions and/or higher doses. There is evidence suggesting that the time duration of paclitaxel concentrations maintained above 0.1 μM/L (T>0.1 μM ) is associated with improved survival and development of toxicity. On the other hand, currently there is no information relating opti mal systemic exposure of docetaxel to efficacy and toxicity. In addition, these pharmacokinetic-pharma codynamic relationship may change with therapy with antineoplastic agents and other agents adminis tered concurrently, and necessitates additional phar macokinetic-pharmacodynamic investigations.

Efficacy and Safety Assessment of Paclitaxel in Patients with Docetaxel-Resistant Esophageal Squamous Cell Carcinoma

Background: Incomplete cross-resistances between paclitaxel (PTX) and docetaxel (DTX) has been demonstrated in several types of cancer. The objective of the present study was to assess the existence of cross-resistance between PTX and DTX in esophageal squamous cell carcinoma. Methods: Patients in the PTX group received PTX without DTX pretreatment, patients in the prior DTX (Pr-DTX) group received PTX after the development of resistance to DTX, and patients in the DTX group received DTX without subsequent PTX treatment. Results: A total of 73 patients were enrolled. The response rates to PTX in the PTX and Pr-DTX groups were 22.7 and 20.0%, respectively. The median progression-free survival times from the first day of PTX treatment in the PTX and Pr-DTX groups were 113 (95% CI 56-154) and 97 days (95% CI 36-189), respectively. The median overall survival times from the first day of DTX treatment in the Pr-DTX and DTX groups were 315 (95% CI 124-453) and 148 days (95% CI 139-177), respectively. Conclusions: There is no or incomplete clinical cross-resistance between PTX and DTX in esophageal squamous cell carcinoma. Replacement of DTX with PTX is a suitable treatment option for patients with DTX-resistant esophageal squamous cell carcinoma.

Taxanes: impact on breast cancer therapy

Taxanes play an important role in the management of early-stage and advanced-stage breast cancer. Initial studies sought to determine whether there was antitumor activity in patients with metastatic disease, and identify the optimal agent, dose, and schedule. Subsequent studies established a role for both paclitaxel and docetaxel as adjuvant therapy, determined whether they should be administered concurrently or sequentially with other cytotoxic agents, and also determined the optimal agent, dose, and schedule. Taxanes have also been combined with biologic agents, including anti-HER2-directed therapy and antiangiogenic therapy. The aim of this article is to provide a review of pivotal trials evaluating taxane therapy that have informed the current approach for the use of taxanes in early-stage and advanced-stage breast cancer.

Paclitaxel-based versus docetaxel-based regimens in metastatic breast cancer: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVES

Docetaxel and paclitaxel show significant clinical activity in metastatic breast cancer (MBC) and have been approved for MBC by the U.S. Food and Drug Administration, but it is still unclear whether a paclitaxel-based regimen improves outcomes over a docetaxel-based regimen in patients with MBC. We therefore performed a meta-analysis of randomized controlled trials to compare the safety and efficacy of these two regimens in MBC.

METHODS

We systematically searched for randomized controlled trials that comparing paclitaxel-based with docetaxel-based regimens in patients with MBC in PubMed (up to January 2012), Embase (1980 to January 2012), and the Cochrane databases (up to January 2012). Abstracts presented at conferences (up to January 2011) were also searched. Data were extracted from the studies by two independent reviewers. The meta-analysis was performed by Stata version 12.0 software (Stata Corporation, College Station, TX, USA).

RESULTS

Seven eligible trials involving 1694 patients with MBC were selected. Our results showed that a paclitaxel-based regimen was comparable to a docetaxel-based regimen for MBC patients in terms of OS (HR: 0.87, 95% CI: 0.60-1.27, p = 0.48), PFS (HR: 0.76, 95% CI: 0.58-1.00, p = 0.052), TTP (HR: 1.13, 95% CI: 0.81-1.58, p = 0.46), and ORR (RR: 1.01, 95% CI: 0.88-1.15, p = 0.92), but fewer grade 3 or 4 adverse events including anemia (RR: 0.64, 95% CI: 0.44-0.94, p = 0.023), neutropenia (RR: 0.74, 95% CI: 0.58-0.93, p = 0.011), febrile neutropenia (RR: 0.38, 95% CI: 0.15-0.96, p = 0.041), thrombopenia (RR: 0.62, 95% CI: 0.41-0.96, p = 0.033), mucositis (RR: 0.082, 95% CI: 0.025-0.27, p < 0.001), diarrhea (RR: 0.19, 95% CI: 0.081-0.47, p < 0.001) and fatigue (RR: 0.43, 95% CI: 0.20-0.96, p = 0.039) were observed in the paclitaxel-based regimen. However, limitations of our study needed to be considered when interpreting these results: our study was a meta-analysis of published data, and there was significant heterogeneity among included trials. Potential publication bias might also exist.

CONCLUSION

The present systematic review and meta-analysis demonstrates that both taxane-based regimens have comparable efficacy for patients with MBC, and the paclitaxel-based regimen is associated with less toxicity and better tolerability, especially in older patients and when used in weekly regimens.

Effect of dose and dosage interval on the oral bioavailability of docetaxel in combination with a curcumin self-emulsifying drug delivery system (SEDDS)

The present study investigated the effects of a curcumin self-emulsifying drug delivery systems (SEDDS) on the pharmacokinetics of orally administered docetaxel in rats. A single dose of docetaxel was orally administered (30 mg/kg) alone or after oral curcumin SEDDS (25, 50, 100 and 150 mg/kg) administration with time intervals of 0, 15 and 30 min, respectively. After oral administration, the C (max) and the area under the plasma concentration-time curve (AUC) of docetaxel were significantly increased (0 min, p < 0.05; 15 and 30 min, p < 0.01) by 2.2, 4.7 and 4.6 times and 2.0, 3.8 and 4.1 times compared to that of control group, respectively, after treatment with curcumin SEDDS (100 mg/kg) for each interval. Moreover, The C (max) of docetaxel was increased by 2.6 and 4.4 times in response to 25 and 50 mg/kg curcumin SEDDS treatment, respectively, the corresponding AUC was increased by about 2.4 and 3.1 times, and consequently the absolute bioavailabilities of docetaxel in these two treatment groups were 7.9 and 10.4%, respectively, which showed a significant increase of about 2.4- and 3.2-fold in comparison to the control value (3.3%). However, no further increase in either AUC or C (max) values of docetaxel was observed as the curcumin SEDDS dose was increased from 50 to 150 mg/kg. It is worth noting that the presence of curcumin SEDDS did not significantly decrease the systemic clearance, which was shown by the almost unchanged terminal half-life (t (1/2)) of docetaxel in all treatment groups. Thus, the enhanced bioavailability of oral docetaxel by curcumin SEDDS seemed to be likely due to an inhibition function of cytochrome P450 (CYP) 3A and P-glycoprotein (Pgp) in the intestines of the rats. However, further in vivo studies are needed to verify these hypotheses.

A phase I/II trial of non-pegylated liposomal doxorubicin, docetaxel and trastuzumab as first-line treatment in HER-2-positive locally advanced or metastatic breast cancer

AIM

To assess the activity and safety of non-pegylated liposomal doxorubicin (Myocet®) in combination with docetaxel and trastuzumab as first-line treatment of patients with HER-2/neu-positive metastatic breast cancer (MBC).

PATIENTS AND METHODS

The maximum tolerated dose of the combination was defined in the phase I part of the study. In the phase II part, 45 HER-2/neu-positive MBC patients were enrolled to receive 6-8 cycles of Myocet® 50 mg/m2 (day 1), docetaxel 30 mg/m2 (days 2 and 9) plus trastuzumab (day 2, 4 mg/kg followed by 2 mg/kg/week) every 21 d until unacceptable toxicity or progression occurred. Objective response (primary end-point) and treatment tolerability were assessed according to World Health Organisation criteria. Cardiotoxicity was defined as signs and/or symptoms of congestive heart failure and/or a decrease in left ventricular ejection fraction (LVEF).

RESULTS

The overall response rate was 55.6% (complete response 8.9%, partial response 46.7%), with a median time-to-progression of 10.9 months (C.I. 8.7-15.0). Median overall survival was not reached. The most frequent grade 3-4 adverse events were granulocytopaenia (60.0%), leukocytopenia (43.2%) and alopecia (35.6%). Grade 3-4 diarrhoea, pain, oral and skin toxicity (4.4%, each) and nausea/vomiting, thrombocytopenia and elevated alkaline phosphatase (2.2%, each) were also reported. In 2 patients LVEF fell to <50%, with a decrease from baseline>15%. LVEF median values remained stable from baseline to the end of the study (60%).

CONCLUSIONS

The combination of Myocet®, docetaxel and trastuzumab is safe and shows promising activity as first-line treatment of HER-2-positive MBC.

Radiation-sensitizing effect of low-concentration docetaxel on human esophageal squamous cell carcinoma cell lines

Esophageal squamous cell carcinoma (ESCC) is more sensitive to radiation and chemotherapy than other cancers of the digestive system, and combined modality therapy may represent a promising treatment method. The radiation-sensitizing effect of docetaxel on ESCC cell lines was investigated. A colony formation assay was performed in which ESCC cell lines (TE2, TE3) and A431 were exposed to docetaxel (from 1.0×10(-11) to 10(-7) M) for 3 h to determine the concentration of docetaxel that was not able to kill individual cells (i.e., the non-cytocidal concentration). Individual cell lines were then exposed to the non-cytocidal concentration of docetaxel prior to, during, and after irradiation to determine whether the timing of docetaxel administration affected cell survival. In addition, flow-cytometry was performed, and the cell cycle was examined prior to and after docetaxel exposure to assess the mechanism of docetaxel as a radiation sensitizer. Docetaxel exhibited a concentration-dependent cytocidal effect, with a different IC(50) for each cell type. Almost no cytocidal effect was observed at the following docetaxel concentrations: A431, ≤1.0×10(-10) M; TE-2 and TE-3, ≤1.0×10(-9) M. Concurrent treatment with docetaxel and radiation tended to decrease cell survival in all the cell lines compared with docetaxel or radiation alone. Cell survival was lowest when the cells were treated using X-ray irradiation after docetaxel exposure (p<0.05). Flow cytometry revealed that in all three cell lines, docetaxel exposure increased the G2/M cell fraction with a higher increase in the cell line that exhibited the highest radiosensitivity. This study demonstrated that the administration of docetaxel at a non-cytocidal concentration prior to radiotherapy produced a synergistic cell-killing effect in SCC cell lines.

The microtubule as a breast cancer target

Manifestations of non-equilibrium polarity, random transgressions, and catastrophes are not conditions usually associated with a sense of normalcy. Yet these disquieting features distinguish a utilitarian behavior known as dynamic instability, the signature characteristic of the microtubule. Long known to be a tumor target, disruption of this fragile attribute is associated with some of the most effective agents used to treat breast cancer today. Although the biology of the microtubule is under intense investigation much still remains unknown. As such, our understanding of regulatory molecules and resistance mechanisms are still rudimentary, further compromising our ability to develop novel therapeutic strategies to improve microtubule inhibitors. This review focuses on several classes of anti-microtubule agents and their effects on the functional dynamics of the targeted polymer. The primary objective is to critically examine the molecular mechanisms that contribute to tumor cell death, tumor-resistance, and incident neurotoxicity.

Impact of MAGE-A antigens on taxane response in oral squamous cell carcinoma

MAGE-A antigens are a subgroup of cancer/testis antigens that are exclusively expressed in malignant cells. Only scarce information on the function of MAGE-A antigens is available. There is some evidence that they may influence the response to chemotherapeutic drugs. This study aimed to evaluate the impact of the MAGE-A antigen subgroups MAGE-A2, -A3, -A4 and -A6 on oral squamous cell carcinoma cell lines treated with docetaxel and paclitaxel. Five oral squamous cell carcinoma cell lines were characterized for their quantitative expression of MAGE-A2, -A3, -A4 and -A6. The cell lines were treated with concentrations ranging from 0.025 to 0.8 μM of docetaxel and paclitaxel. The amount of viable cells after 24 and 48 h was measured. The measurements were statistically correlated with MAGE-A expression. All cell lines responded to docetaxel and paclitaxel. One cell line showed a statistically significant weaker response to the taxane treatment. This cell line was the only one that expressed MAGE-A4. MAGE-A4 has a statistically significant impact on the tumour response to docetaxel and paclitaxel in oral squamous cell carcinoma. This may influence treatment options and the course of the disease. Therefore, patients should be evaluated for MAGE-A4 expression before treatment with taxanes.

Paclitaxel combined with ifosfamide in anthracycline- and docetaxel-pretreated metastatic breast cancer: activity independence of prior docetaxel resistance

BACKGROUND

We evaluated the efficacy and tolerability of combined paclitaxel and ifosfamide in anthracycline- and docetaxel-pretreated metastatic breast cancer (MBC).

METHODS

Patients received paclitaxel (175 mg/m(2) i.v. in a 3-h infusion) on day 1 and ifosfamide (1.5 g/m(2) i.v. in a 15-min infusion) on days 1-3, every 3 weeks for a maximum of nine cycles. The tumor response was assessed every two cycles.

RESULTS

We enrolled 34 patients with a median age of 50 years. Thirty patients had visceral metastases. Anthracycline- and docetaxel-based chemotherapy had previously been administered to 18/13 and 13/21 patients, respectively, in (neo)adjuvant/metastatic settings. Three patients had not previously received anthracycline due to abnormal cardiac functions. A total of 174 cycles of chemotherapy were delivered with a median of six cycles. The response rate under the intent-to-treat analysis was 23.5% (all partial responses) with a median response duration of 14 months. The disease control rate was 70.6%. The median progression-free and overall survival were 5.9 and 8.5 months, respectively. There was no apparent relationship between activity and prior docetaxel resistance. The incidence of grade III/IV neutropenia was 46.6% (81 of 174 cycles) with febrile neutropenia of only 1.7%. Major grade III/IV non-hematological toxicities included peripheral neuropathy (6 of 34 patients) and infection (4 of 34 patients). There were no treatment-related deaths.

CONCLUSION

Paclitaxel combined with ifosfamide was effective and tolerable in anthracycline-/docetaxel-pretreated MBC. Overcoming docetaxel resistance by using paclitaxel in combination with ifosfamide needs to be addressed through further investigation.

A phase II study of oxaliplatin, docetaxel, and GM-CSF in patients with previously treated advanced melanoma

PURPOSE

Although much focus has been placed on immunotherapy for melanoma, further development of chemotherapy approaches is needed. Melanoma is responsive to platinum compounds and taxanes, but there is limited experience with combinations of these agents. Oxaliplatin has been reported to have detectable activity in melanoma, and a phase I study has identified a tolerable dose and schedule of oxaliplatin in combination with docetaxel and hematopoietic growth factor support. GM-CSF has a theoretical advantage of immune potentiation. These considerations supported the study of oxaliplatin, docetaxel, and GM-CSF in patients with advanced melanoma.

METHODS

Eligibility included adequate organ function, PS<or=2, at most one prior chemotherapy and one prior immunotherapy, no prior treatment with oxaliplatin or taxanes and no chremophor allergy. After premedication, docetaxel was administered day 1 at 75 mg/m2, then oxaliplatin on day 2 at 85 mg/m2. GM-CSF (250 mcg/m2) was administered s.c. days 3-12. Cycles were 21 days in length, and disease reevaluation was performed every two cycles by RECIST criteria.

RESULTS

Nineteen patients received at least one cycle, eight with one prior systemic therapy, five with two prior systemic therapies. Five patients did not complete two cycles and were not formally evaluable for response. Five patients had stable disease (SD), including one who failed two prior therapies and went on to receive ten cycles. The remaining nine patients displayed progressive disease (PD) after two cycles. Notable toxicities included seven cases (37%) of grade III/IV neutropenia and two (11%) hypersensitivity reactions.

CONCLUSIONS

This combination of oxaliplatin, docetaxel, and GM-CSF has limited clinical activity in previously treated patients with advanced melanoma. Exploration in treatment-naïve patients may still be warranted.

Paclitaxel and docetaxel in the treatment of breast cancer

BACKGROUND

Paclitaxel and docetaxel are considered fundamental drugs in the treatment of breast cancer.

OBJECTIVES

To review the current role of taxanes in the treatment breast cancer, with emphasis on data from randomized trials comparing the two taxanes.

METHODS

We have reviewed the available evidence in the literature to gauge the results of therapy of early and advanced breast cancer with taxanes.

RESULTS

Clinically benefits were first shown in metastatic setting. More recently, benefits have also been seen in the therapy of early-stage disease. It seems reasonable to consider either drug as standard treatment for node-positive early stage or metastatic breast cancer. Future studies should explore the optimal way of combining taxanes with novel biological and cytotoxic drugs.

CONCLUSION

Based on existing evidence, clinicians should choose a taxane-based regimen for their patients, according to clinical activity, toxicity profile, pharmacokinetics, and a dosing schedule that best meets the therapeutic needs and convenience.

An economic evaluation of docetaxel and paclitaxel regimens in metastatic breast cancer in the UK

Paclitaxel and docetaxel have been available for the treatment of metastatic breast cancer (MBC) since the 1990s. However, until very recently, comparisons between these two drugs have been difficult due to lack of direct comparative clinical evidence and differences in trial patient populations. To conduct a cost-effectiveness analysis comparing docetaxel with paclitaxel regimens in the treatment of MBC previously treated with an anthracycline from the perspective of the UK NHS. A cost-utility analysis was performed using a Markov model to compare taxanes in MBC patients who had progressed after treatment with an anthracycline-containing chemotherapy regimen: docetaxel 100 mg/m2 1-hour intravenous (IV) infusion every 21 days versus paclitaxel 175 mg/m2 3-hour IV infusion every 21 days (Pac3w). In parallel, additional analyses were performed versus paclitaxel administered in 1-weekly cycles (Pac1w), and a nano albumin-bound form of paclitaxel (Nab-P) given every 3 weeks. Progression-free survival (PFS), overall survival (OS) and adverse events used in the model were derived from a randomized trial directly comparing docetaxel with Pac3w; the comparisons of docetaxel versus the other two paclitaxel regimens were indirect, using patient-level data from a trial comparing Pac3w with Pac1w, and from the published literature comparing Pac3w with Nab-P. Utility values for response, progression and adverse events were derived from the literature. Direct treatment costs related to progression, best supportive care and adverse events were estimated using clinical trials data, published literature, NHS reference costs and published drug prices. The estimated costs of growth colony-stimulating factors and blood transfusion were also included in the model. The model was used to predict the expected total costs ( pound, year 2005-6 values), QALYs gained, incremental cost/life-year gained (LY) and cost/QALY over a 10-year time period. In the base-case analysis, docetaxel improved QALYs by 0.33, 0.29 and 0.22 compared with Pac3w, Pac1w and Nab-P, respectively. The incremental cost-effectiveness ratios (ICERs) for docetaxel were pound 12 032/QALY versus Pac3w, pound 4583/QALY versus Pac1w and pound 14 ,694/QALY versus Nab-P. The ICER was sensitive to the hazard ratios for PFS and OS between the comparators, the drug cost of initial treatment and the treatment costs after progression. Taking into account parameter uncertainty, and comparing all four treatments simultaneously, at a willingness to pay of pound 20,000 per QALY gained, the probability of docetaxel being the most cost-effective treatment was around 70%. In the base-case scenario, docetaxel compared with Pac3w is estimated to have a cost-effectiveness ratio that falls within the acceptable threshold in the UK. The study also suggests that docetaxel may be cost effective versus Pac1w and Nab-P, although there is more uncertainty around these findings.

Docetaxel as salvage therapy in highly pretreated and drug resistant gastrointestinal carcinomas

Introduction

Despite many efforts to develop new chemotherapies for metastatic upper gastrointestinal (GI) cancer, overall prognosis continues to be fatal, particularly in gastric and pancreatic cancer. Many of these patients deserve second-or third-line treatment after failure of first-line chemotherapy. Therefore, we analysed toxicity and response rate of weekly docetaxel after failed upfront regimes in these upper GI cancer patients.

Patients and Methods

Between 2001 and 2006, 18 patients received docetaxel based regimes (35 mg/m² weekly) after informed consent. Response rates were determined using RECIST criteria or tumor progression if clinically evident. Toxicities were graded based on NCI CTC criteria (version 2). Most patients had gastric cancer (13/18). The remaining entities comprised of bilio-pancreatic cancer (5/18).

Results

Docetaxel was administered as 2nd line therapy in 28% (5/18), 3rd line therapy in 56% (10/18) and 4th or 5th line therapy in 17% (3/18). The average docetaxel dose was 38 mg/m² (Median: 35 mg/m²) once weekly. Over a treatment duration of 14.7 weeks, the average dosage was 58 gr per patient and week. Overall, docetaxel was well tolerated with only few chemotherapy-associated toxicities (Grade 3/4), including nausea (17%), polyneuropathy (17%), anorexia (11%), neutropenia (6%) and leukopenia (17%).

Docetaxel administration did not achieve any complete responses (CR) and one (5.6%) partial response (PR) was seen (1/18). In addition 5 patients (27.8%) had stable disease (SD), thus inducing a tumor control rate of 33.3% (6/18). Median progression-free survival was 2.4 months for all patients, 2.1 months in the gastric-cancer and 2.4 months in the bilio-pancreatic cancer subgroups respectively. After first docetaxel administration median survival for all patients was 4.5 months, patients with gastric cancer survived for 4.9 months whereas patients suffering from bilio-pancreatic carcinoma survived for 4.2 months. However, taken together 27% (5/18) had a remarkable overall survival of more than 2.5 years.

Discussion

In severely pretreated patients, with documented chemoresistant GI tumors, weekly docetaxel was well tolerated, presented good tumor control rate and overall survival. Therefore, this regimen may be used as salvage treatment in individual patients with upper GI cancers.

The multidisciplinary management of gastrointestinal cancer. Multimodal treatment of gastric cancer

Although radical surgical R0 resections are the basis of cure for gastric cancer, surgery alone only provides long-term survival in 20-30% of patients with advanced-stage disease. Thus, in Western and European countries, advanced gastric cancer has a high risk of recurrence and metachronous metastases. Very recently, multimodal strategies combining different neoadjuvant and/or adjuvant protocols have improved the prognosis of gastric cancer when combined with surgery with curative intent. As used in palliative regimens, the combination of cisplatin with intravenous or oral fluoropyrimidines has been the integral component of such (neo)adjuvant strategies. However, the cytotoxic agents docetaxel, oxaliplatin and irinotecan and new targeted biologicals such as cetuximab, bevacizumab or panitumumab are currently under investigation, with or without irradiation, in multimodal treatment regimens. These studies may further increase R0 resection rates, and prolong disease-free and overall survival times in the treatment of advanced gastric cancer. This article reviews the most relevant literature on multimodal treatment of gastric cancer, and discusses future strategies to improve locoregional failures.

Naringin, a grapefruit flavanone, protects V79 cells against the bleomycin-induced genotoxicity and decline in survival

The effect of naringin, a grapefruit flavonone was studied on bleomycin-induced genomic damage and alteration in the survival of cultured V79 cells. Exposure of V79 cells to bleomycin induced a concentration dependent elevation in the frequency of binucleate cells bearing micronuclei (MNBNC) and a maximum number of MNBNCs were observed in the cells treated with 50 microg ml(-1) bleomycin, the highest concentration evaluated. This genotoxic effect of bleomycin was reflected in the cell survival, where a concentration dependent decline was observed in the cells treated with different concentrations of bleomycin. Treatment of cells with 1 mm naringin before exposure to different concentrations of bleomycin arrested the bleomycin-induced decline in the cell survival accompanied by a significant reduction in the frequency of micronuclei when compared with bleomycin treatment alone. The cell survival and micronuclei induction were found to be inversely correlated. The repair kinetics of DNA damage induced by bleomycin was evaluated by exposing the cells to 10 microg ml(-1) bleomycin using single cell gel electrophoresis. Treatment of V79 cells with bleomycin resulted in a continuous increase in DNA damage up to 6 h post-bleomycin treatment as evident by migration of more DNA into the tails (% tail DNA) of the comets and a subsequent increase in olive tail moment (OTM), an index of DNA damage. Treatment of V79 cells with 1 mm naringin reduced bleomycin-induced DNA damage and accelerated DNA repair as indicated by a reduction in % tail DNA and OTM with increasing assessment time. A maximum reduction in the DNA damage was observed at 6 h post-bleomycin treatment, where it was 5 times lower than bleomycin alone. Our study, which was conducted on the basis of antioxidant, free radical scavenging and metal chelating properties of naringin demonstrates that naringin reduced the genotoxic effects of bleomycin and consequently increased the cell survival and therefore may act as a chemoprotective agent in clinical situations.

Docetaxel in the management of ovarian cancer

Standard first-line treatment for Stage IC-IV ovarian cancer is currently a platinum agent or a combination of a platinum agent with a taxane. The use of a taxane compound in addition to single-agent platinum is increasingly preferred to platinum alone. In countries such as the UK, the taxane paclitaxel has been approved by the government for first-line use. However, it has yet to receive US Food and Drug Administration approval in the USA for use in this context. Typically, in countries such as the UK, patients with advanced ovarian cancer receive a combination of paclitaxel and carboplatin first line, both drugs given 3-weekly by intravenous infusion. Subsequent trials have demonstrated that the second-generation taxane docetaxel can be used as a substitute for paclitaxel; sharing many of its actions but with a different toxicity profile. However, docetaxel has not yet received approval for standard use. Here, the clinical development of docetaxel and its present and future place in the management of ovarian cancer is discussed.

Randomized Phase III Study of Docetaxel Compared With Paclitaxel in Metastatic Breast Cancer

Purpose

This randomized, controlled, multicenter, open-label, phase III study compared docetaxel versus paclitaxel in patients with advanced breast cancer that had progressed after an anthracycline-containing chemotherapy regimen.

Patients and Methods

Patients (n = 449) were randomly assigned to receive either docetaxel 100 mg/m2(n = 225) or paclitaxel 175 mg/m2(n = 224) on day 1, every 21 days until tumor progression, unacceptable toxicity, or withdrawal of consent.

Results

In the intent-to-treat population, both the median overall survival (OS, 15.4 v 12.7 months; hazard ratio [HR], 1.41; 95% CI, 1.15 to 1.73; P = .03) and the median time to progression (TTP, 5.7 months v 3.6 months; HR, 1.64; 95% CI, 1.33 to 2.02; P < .0001) for docetaxel were significantly longer than for paclitaxel, and the overall response rate (ORR, 32% v 25%; P = .10) was higher for docetaxel. These results were confirmed by multivariate analyses. The incidence of treatment-related hematologic and nonhematologic toxicities was greater for docetaxel than for paclitaxel; however, quality-of-life scores were not statistically different between treatment groups over time.

Conclusion

Docetaxel was superior to paclitaxel in terms of OS and TTP. ORR was higher for docetaxel. Hematologic and nonhematologic toxicities occurred more frequently in the docetaxel group. The global quality-of-life scores were similar for both agents over time.

Phase I and pharmacokinetic study of docetaxel combined with melphalan and carboplatin, with autologous hematopoietic progenitor cell support, in patients with advanced refractory malignancies

The purpose of this study was to define the maximal tolerated dose (MTD), extramedullary toxicities, and pharmacokinetics of docetaxel combined with high-dose melphalan and carboplatin with autologous hematopoietic progenitor cell support. Fifty-nine patients with advanced refractory malignancy (32 breast cancer, 10 non-Hodgkin lymphoma, 6 germ cell tumors, 4 Hodgkin disease, 4 ovarian cancer, 2 sarcoma, and 1 unknown primary adenocarcinoma) with a median of 3 prior chemotherapy regimens and a median of 3 organs involved were enrolled. Treatment included docetaxel (150-550 mg/m2 infused over 2 hours on day -6), melphalan (150-165 mg/m2 infused over 15 minutes from day -5 to -3), and carboplatin (1000-1300 mg/m2 as a 72-hour continuous infusion from day -5). Five patients died from direct regimen-related organ toxicity (2 capillary leak syndrome, 2 enterocolitis, and 1 hepatic toxicity), and 1 additional patient died from pulmonary aspergillosis. The docetaxel MTD was defined as 400 mg/m 2 , combined with melphalan (150 mg/m2 ) and carboplatin (1000 mg/m2 ). The MTD cohort was expanded to enroll a total of 26 patients, 1 of whom died from toxic enterocolitis. The remaining 25 patients presented the following extramedullary toxicity profile, which was manageable and largely reversible: stomatitis, myoarthralgias, peripheral neuropathy, gastrointestinal and cutaneous toxicities, and syndrome of inappropriate antidiuretic hormone secretion. Docetaxel exhibited linear pharmacokinetics in the dose range tested (150-550 mg/m2 ). Pharmacodynamic correlations were noted between the docetaxel area under the curve and peripheral neuropathy or stomatitis. The response rate among 38 patients with measurable disease was 95%, with 47% complete responses. At a median follow-up of 26 months (range, 7-72 months), the 3-year event-free survival and overall survival were 26% and 36%, respectively. In conclusion, a 4-fold dose escalation of docetaxel, combined with melphalan and carboplatin, is feasible with autologous hematopoietic progenitor cell support. The notable activity of this regimen in treatment-refractory patients warrants its further evaluation.

Docetaxel-based chemotherapy as second-line treatment for paclitaxel-based chemotherapy-resistant hormone-refractory prostate cancer: A pilot study

OBJECTIVES

To examine docetaxel (DTX)-based chemotherapy in paclitaxel (PTX)-based chemotherapy-resistant hormone-refractory prostate cancer (HRPC) to investigate the activity and degree of toxicity in a pilot study. We have previously reported on the effectiveness of combination chemotherapy with PTX, estramustine (EMP), and carboplatin against HRPC. Although many patients with HRPC initially responded to this PTX/EMP-based combination chemotherapy, most finally progressed to PTX-resistant status within a mean of less than 1 year. DTX is an inhibitor of microtubule depolymerization like PTX and has demonstrated activity against PTX-resistant metastatic tumors.

METHODS

The subjects were 15 patients with HRPC who displayed disease progression while receiving PTX/EMP/carboplatin combination chemotherapy. The patients were treated with intravenous DTX 30 mg/m2 weekly, oral EMP 10 mg/kg daily, and intravenous carboplatin (dosed to an area under the curve of 6) on day 1 of every 4-week cycle. Treatment was continued until disease progression or excessive toxicity.

RESULTS

Each patient received a median of eight consecutive cycles. The prostate-specific antigen level decreased by 50% or more in 33.3% of patients and by 90% or more in 13.3%. The median follow-up was 49.6 weeks, with median time to progression of 25.0 weeks and median overall survival of 54.0 weeks. One patient died of interstitial pneumonitis. One patient developed secondary osteomyelodysplastic syndrome. The major severe toxicities were grade 3 or 4 anemia in 66.7% of patients, leukopenia in 26.7%, and thrombocytopenia in 40.0%.

CONCLUSIONS

The results of our study have shown that DTX is comparatively active for heavily pretreated patients with PTX-resistant HRPC. However, given the significant toxicities and small subject population, well-designed Phase I-II trials of the improved regimen are warranted.

Phase III randomized trial of docetaxel-carboplatin versus paclitaxel-carboplatin as first-line chemotherapy for ovarian carcinoma

BACKGROUND

Chemotherapy with a platinum agent and a taxane (paclitaxel) is considered the standard of care for treatment of ovarian carcinoma. We compared the combination of docetaxel-carboplatin with the combination of paclitaxel-carboplatin as first-line chemotherapy for stage Ic-IV epithelial ovarian or primary peritoneal cancer.

METHODS

We randomly assigned 1077 patients to receive docetaxel at 75 mg/m2 of body surface area (1-hour intravenous infusion) or paclitaxel at 175 mg/m2 (3-hour intravenous infusion). Both treatments then were followed by carboplatin to an area under the plasma concentration-time curve of 5. The treatments were repeated every 3 weeks for six cycles; in responding patients, an additional three cycles of single-agent carboplatin was permitted. Survival curves were calculated by the Kaplan-Meier method, and hazard ratios were estimated with the Cox proportional hazards model. All statistical tests were two-sided.

RESULTS

After a median follow-up of 23 months, both groups had similar progression-free survival (medians of 15.0 months for docetaxel-carboplatin and 14.8 months for paclitaxel-carboplatin; hazard ratio [HR] docetaxel-paclitaxel = 0.97, 95% confidence interval [CI] = 0.83 to 1.13; P = .707), overall survival rates at 2 years (64.2% and 68.9%, respectively; HR = 1.13, 95% CI = 0.92 to 1.39; P = .238), and objective tumor (58.7% and 59.5%, respectively; difference between docetaxel and paclitaxel = -0.8%, 95% CI = -8.6% to 7.1%; P = .868) and CA-125 (75.8% and 76.8%, respectively; difference docetaxel-paclitaxel = -1.0%, 95% CI = -7.2% to 5.1%; P = .794) response rates. However, docetaxel-carboplatin was associated with substantially less overall and grade 2 or higher neurotoxicity than paclitaxel-carboplatin (grade > or =2 neurosensory toxicity in 11% versus 30%, difference = 19%, 95% CI = 15% to 24%; P<.001; grade > or =2 neuromotor toxicity in 3% versus 7%, difference = 4%, 95% CI = 1% to 7%; P<.001). Treatment with docetaxel-carboplatin was associated with statistically significantly more grade 3-4 neutropenia (94% versus 84%, difference = 11%, 95% CI = 7% to 14%; P<.001) and neutropenic complications than treatment with paclitaxel-carboplatin, although myelosuppression did not influence dose delivery or patient safety. Global quality of life was similar in both arms, but substantive differences in many symptom scores favored docetaxel.

CONCLUSIONS

Docetaxel-carboplatin appears to be similar to paclitaxel-carboplatin in terms of progression-free survival and response, although longer follow-up is required for a definitive statement on survival. Thus, docetaxel-carboplatin represents an alternative first-line chemotherapy regimen for patients with newly diagnosed ovarian cancer.

Rapid analysis of docetaxel in human plasma by tandem mass spectrometry with on-line sample extraction

A simple, rapid, and sensitive analytical method for the measurement of docetaxel in human plasma was developed and validated. The method is based on positive electrospray ionization tandem mass spectrometry (ESI+-MS-MS) with on-line sample extraction. It uses paclitaxel as internal standard for calibration. The on-line sample extraction minimizes sample handling and is readily adopted for automation. Quantitation of plasma docetaxel was done by the multiple reaction monitoring (MRM) mode. The method had a linear calibration range of 1.00-3000 ng/mL with a correlation coefficient >0.9999. The limit of quantitation (LOQ) for docetaxel in plasma was 1.00 ng/mL. The on-line extraction recovery of docetaxel was between 86.1-94.7%, with %CV < or = 6.1%. This method has high accuracy (90.1-96.3%), and excellent intra-assay (0.6-3.8%) and inter-assay (2.0-5.7%) precision. Its applicability to clinical samples was demonstrated by measuring patient plasma samples after treatment of weekly docetaxel at 25 mg/m2 as 60-min infusion.

Preclinical pharmacology of the taxanes: implications of the differences

Taxanes are one of the most powerful classes of compounds among all chemotherapeutic drugs. Only 30 years separate the isolation of the first taxane from the results of direct clinical comparisons in metastatic breast, ovarian, and lung cancer between the two taxanes available in routine clinical practice. These results suggest a more favorable benefit-to-risk ratio for docetaxel compared to paclitaxel when these drugs are used as single agents or in combination with other chemotherapeutic agents in an every-3-week dosing regimen. Pharmacological data support the difference between the taxanes, likely explaining the clinical results. Considering the molecular pharmacology of the two drugs, docetaxel appears to bind to beta-tubulin with greater affinity and has a wider cell cycle activity than paclitaxel. Docetaxel also appears to have direct antitumoral activity via an apoptotic effect mediated by bcl-2 phosphorylation. In addition, docetaxel has a longer retention time in tumor cells than paclitaxel because of greater uptake and slower efflux. Pharmacokinetics and pharmacodynamics of the taxanes show both agents to be extensively metabolized in the liver, and paclitaxel has a nonlinear pharmacokinetic behavior while docetaxel has linear pharmacokinetics. These differences explain the more simple treatment schedule and favorable results for docetaxel as a single agent and in combination therapy. Last, but not least, there is a pharmacokinetic interaction between paclitaxel and the anthracyclines, an active class of compounds commonly used in the treatment of breast cancer. This pharmacokinetic interaction is associated with greater cardio- and myelotoxicities, which are sequence dependent. These pharmacological data likely explain the different clinical development strategies for the two molecules as well as the different clinical results from individual trials and direct comparisons.

Docetaxel: an alternative taxane in ovarian cancer

The taxanes paclitaxel and docetaxel are potent chemotherapeutic agents that block tubulin depolymerisation, leading to the inhibition of microtubule dynamics and cell cycle arrest. Although docetaxel and paclitaxel share a mutual tubulin binding site, mechanistic and pharmacological differences exist between these agents. For example, docetaxel has increased potency and an improved therapeutic index compared with paclitaxel, and its short 1-h infusion offers a substantial clinical advantage over the prolonged infusion durations required with paclitaxel. In clinical studies, docetaxel monotherapy demonstrated good response rates and an acceptable toxicity profile in both paclitaxel- and platinum-refractory ovarian cancer patients. In particular, neurotoxicity — a dominant side effect with both paclitaxel and cisplatin — occurs at a low incidence with docetaxel, making docetaxel a promising agent for combining cisplatin and other platinum compounds. In Phase II studies, the combination of docetaxel with either cisplatin or carboplatin has yielded impressive response rates of 69–74 and 81–87%, respectively. Furthermore, Phase III data suggest that docetaxel–carboplatin and paclitaxel–carboplatin are similarly efficacious with respect to progression-free survival and clinical response, although neurotoxicity occurs more frequently with the paclitaxel regimen. While paclitaxel–carboplatin remains the standard treatment for the management of advanced ovarian cancer, docetaxel–carboplatin appears to be a promising alternative, particularly in terms of minimising the incidence and severity of peripheral neuropathy.

Docetaxel with concurrent radiotherapy in head and neck cancer

Recent studies in the treatment of head and neck cancer suggest that combined chemoradiation is superior to radiation alone with regard to local-regional control. Agents that have shown activity as radiosensitizers include platinum agents and taxanes. Docetaxel is a semisynthetic taxane that affects polymerized tubulin both to promote microtubule formation and to inhibit its disassembly. As a single agent, docetaxel shows significant antitumor activity in head and neck cancer in the neoadjuvant setting. Docetaxel also exhibits potent radiosensitizing capability. Because docetaxel is a phase-specific agent, frequent administration of docetaxel offers the potential for enhancement of radiosensitization. Current trials are exploring the optimal dose and schedule of administration of docetaxel with concurrent radiotherapy in patients with head and neck cancer.

AMD473 (ZD0473) exhibits marked in vitro anticancer activity in human tumor specimens taken directly from patients

AMD473 (ZD0473; cis-amminedichloro[2-methylpyridine]platinum [II]) is a new generation anticancer agent that, in preclinical studies, shows evidence of an extended spectrum of antitumor activity and overcomes platinum resistance mechanisms. Here we evaluate the activity of AMD473 (ZD0473) in a panel of 120 human tumor specimens using a soft agar cloning assay (human tumor colony-forming assay). When tumor cells were treated with 1.0, 4.0 or 16.0 microg/ml AMD473 (ZD0473) for 2 h, in vitro responses were observed in 18% (9/51), 33% (17/51) and 44% (19/43) of assessable specimens. Treatment of tumor cells with the same concentrations of AMD473 (ZD0473) for 24 h resulted in responses of 33% (16/48), 63% (30/48) and 85% (35/41). AMD473 (ZD0473) (16 microg/ml; 24 h) demonstrated activity towards 100% of the non-small cell lung (5/5) and ovarian (8/8) cancer specimens and 73% (8/11) of the breast cancer specimens treated. Low levels of cross-resistance to cisplatin cyclophosphamide, 5-flurouracil, etoposide and gemcitabine were observed. There was a positive relationship between AMD473 (ZD0473) concentration and effect, and a significant difference between response to 2- versus 24-h exposure to 4 or 16 microg/ml (p=0.003 and p=0.001, respectively). These responses demonstrate efficacy at pharmacologically relevant concentrations, suggesting AMD473 (ZD0473) deserves further evaluation.

Decreased response to paclitaxel versus docetaxel in HER-2/neu transfected human breast cancer cells

Taxanes are effective in the treatment of metastatic breast cancer. Docetaxel has been shown to be more potent than paclitaxel in inducing bcl-2 phosphorylation and apoptosis and is clinically active in some paclitaxel-resistant breast tumors. HER-2/neu overexpression has been shown to correlate with resistance to hormonal therapy as well as chemotherapy. Using a HER-2/neu transfected MCF-7 human breast cancer cell line, we investigated the role of HER-2/neu overexpression on resistance to paclitaxel and docetaxel treatment. A control vector transfected MCF-7 human breast cancer cell line (MCF/neo) and a HER-2/neu transfected MCF-7 line (MCF/18) were treated with various concentrations of docetaxel or paclitaxel. Cell number was assessed using the MTT tetrazolium dye assay. In the control vector transfected MCF/neo cell line, paclitaxel and docetaxel gave similar dose-dependent growth inhibition ( p = 0.175). In HER-2/neu transfected MCF/18 cells, docetaxel treatment resulted in a dose-dependent inhibition similar to that seen in MCF/neo cells. Paclitaxel, however, gave significantly less growth inhibition than docetaxel in the HER-2/neu overexpressing MCF/18 cells (p = 0.0003). These data suggest that HER-2/neu overexpression may contribute to paclitaxel resistance. In contrast, the cytotoxic effects of docetaxel in these breast carcinoma cells are not affected by HER-2/neu expression. Therefore, docetaxel may be the preferred taxane therapy in HER-2/neu overexpressing breast tumors.

A phase II study of docetaxel in paclitaxel-resistant ovarian and peritoneal carcinoma: a Gynecologic Oncology Group study

OBJECTIVES

Docetaxel is an inhibitor of microtubule depolymerization and has demonstrated activity in paclitaxel-resistant breast cancer and gynecologic cancer. The Gynecologic Oncology Group (GOG) conducted a study of docetaxel in paclitaxel-resistant ovarian and peritoneal carcinoma to determine its activity, and nature and degree of toxicity, in this cohort of patients.

METHODS

Patients with platinum- and paclitaxel-resistant ovarian or peritoneal carcinoma, defined as progression while on or within 6 months of therapy, were eligible if they had measurable disease and had not received more than one chemotherapy regimen. Docetaxel at a dose of 100 mg/m(2) was administered iv over 1 h every 21 days. A prophylactic regimen of oral dexamethasone 8 mg bid was begun 24 h before docetaxel administration and continued for 48 h thereafter. Hepatic function was strictly monitored.

RESULTS

Sixty patients were entered and treated with a total of 256 courses, with all 60 evaluable for toxicity and 58 evaluable for response. Responses were observed in 22.4% of patients, with 5.2% achieving complete response and 17.2% achieving partial response (95% CI, 12.5-35.3%). The median duration of response was 2.5 months. The likelihood of observing a response did not appear to be related to the length of the prior paclitaxel-free interval or duration of prior paclitaxel infusions. The principal adverse effect of grade 4 neutropenia occurred in 75% of patients. There was one treatment-related death. Dose reductions were required in 36% of patients.

CONCLUSIONS

Docetaxel is active in paclitaxel-resistant ovarian and peritoneal cancer but, in view of significant hematologic toxicity, further study is warranted to ascertain its optimal dose and schedule.

Weekly docetaxel/paclitaxel in pretreated metastatic breast cancer

The purpose of our study was to evaluate the feasibility and efficacy of weekly docetaxel/paclitaxel in pretreated advanced breast cancer patients. Twenty-six patients with metastatic breast cancer were included in this study. Three different schedules of treatment were administered. The starting schedule, A1, consisted of docetaxel 60 mg/m2 on day 1 plus paclitaxel 60 mg/m2 over 1 hour, weekly for 18 weeks; this schedule was considered feasible if at least 70% of the planned doses were given on time and without reduction. Schedule A2 consisted of the same doses administered on days 1 and 8 every 3 weeks, and schedule B consisted of docetaxel 25 mg/m2 followed by paclitaxel 40 mg/m2 for 1 hour on days 1 and 8 every 3 weeks for a total of 6 cycles. All patients had received prior anthracyclines, and 19 patients were pretreated with taxanes. Seventy-seven percent of patients had received at least 2 prior lines of chemotherapy. Twenty-five patients are assessable for toxicity and efficacy. A total of 109 cycles of chemotherapy have been administered, with a median of 4 cycles per patient (range, 1-8 cycles). The median delivered dose intensity was 27 mg/m2/week for paclitaxel (range, 18-50 mg/m2/week) and 17 mg/m2/week (range, 12-39 mg/m2/week) for docetaxel. Six patients received schedule A1. This schedule was considered not feasible due to neutropenia grade > 2, mucositis, and diarrhea grade 2, which required dose reduction/omission in 33% of administrations. For this reason, treatment in the following 5 patients was omitted on day 15 (schedule A2). Schedule B was found to be more feasible with 16% of dose reductions/omissions. The overall response rate was 68% (95% CI, 50%-86%) with a median duration of response of 10 months (range, 2-18+ months). Treatment was well tolerated; myelosuppression was rare and grade 3 cutaneous toxicity was observed in only 2 patients. In conclusion, weekly docetaxel/paclitaxel is active at low dosages and was well tolerated as salvage chemotherapy in metastatic breast cancer. This regimen represents a valid option as a salvage treatment in taxane- and anthracycline-pretreated patients.

Docetaxel plus vinorelbine as salvage chemotherapy in advanced breast cancer: a phase II study

PRECIS

Administration of a combined regimen of docetaxel plus vinorelbine every 4 weeks is feasible and shows activity in heavily pretreated patients with advanced breast cancer.

PURPOSE

To determine the activity and tolerance of docetaxel plus vinorelbine in heavily pretreated patients with advanced breast cancer.

METHODS

Thirty-five metastatic breast cancer patients with ECOG performance status of 0-2 received docetaxel (80 mg/m2 given intravenously) on day 1 and vinorelbine (30 mg/m2 given intravenously) on days 1 and 14, every 4 weeks. The median number of prior chemotherapy regimens was 2 (range: 1-4). Twenty-five patients (71.4%) had been treated previously using intensive therapy approaches with peripheral blood-derived stem cell (PBSC) support, including high-dose chemotherapy (11 patients), multicyclic dose-intensive chemotherapy supported with repeated PBSC infusions (seven patients), or both (seven patients). Twenty-eight patients (80%) received previous chemotherapy for metastatic disease. Adjuvant therapy in the remaining seven patients consisted of high-dose chemotherapy and PBSC support or an anthracycline-containing regimen.

RESULTS

The total number of courses was 229, and the median number of courses per patient was 6 (range: 1-16). There was one toxic death (2.8%). Grade 3-4 toxicities included mucositis (17.1%), neutropenia (37.1%), anemia (5.7%), vomiting (2.9%), and asthenia (14.3%). Eighteen patients (58%; 95% CI: 40.6-75.4%) achieved an objective response, including four complete responses (12.9%) and 14 partial responses (45.1%). Overall response rate was 51.4% (95% CI: 34.8-67.9%). After a median follow-up of 20 months (range: 2-42), overall survival was 20 months (95% CI: 16-24), and median time to progression was 13 months (95% CI: 7-19).

CONCLUSION

This combination shows activity and an acceptable toxicity profile in patients with advanced breast cancer.

Monotherapy with paclitaxel as third-line chemotherapy against anthracycline-pretreated and docetaxel-refractory metastatic breast cancer

We describe a patient with anthracycline-pretreated and docetaxel-refractory metastatic breast cancer who achieved a complete response after third-line chemotherapy with paclitaxel. A 59-year-old woman underwent modified radical mastectomy for advanced cancer in her left breast after local arterial neoadjuvant chemotherapy with anthracycline. Postoperatively anthracycline-containing adjuvant therapy was administered. Pulmonary metastases occurred 15 months after surgery, which did not respond to 4 cycles of second-line chemotherapy with docetaxel, given at 60 mg/m(2) every 3 weeks. Therefore 210 mg/m(2) of paclitaxel was given every 3 weeks as third-line monotherapy and induced a complete response with grade 3 neutropenia and hair loss as the major adverse effects. We suggest that paclitaxel is potentially effective as third-line monotherapy for anthracycline-resistant and docetaxel-refractory metastatic breast cancer.

Growth-inhibiting effects of intralesional docetaxel and paclitaxel on an experimental model of malignant neuroectodermal tumor

Taxoids are effective agents against a wide variety of tumors, but their effectiveness on neuroectodermal tumors is not well-known. For this reason we have carried out an experimental study on the effect of intratumoral administration of docetaxel (DC) and paclitaxel (PC) on tumor growth, using a murine model of malignant neuroectodermal tumor. The results showed a delay in tumor growth in animals treated with PC compared with controls (dose of 5 mg/kg, three times per week every other day, forming a cycle; three cycles were completed with a break of a week between each cycle). The total dose administered to each animal was 45 mg/kg. When DC was administered, the results showed distinct tumor growth inhibition and tumor regression in 80% of animals (intratumoral administration at a dose of 5 mg/kg, three times per week every other day forming a cycle; three cycles were completed with a break of a week between each cycle). The total dose administered to each animal was 20 mg/kg. These results suggest the utility of taxoids, mainly DC, by intralesional administration, on malignant tumors of the nervous system.

Selective enhanced phosphorylation of shrimp beta-tubulin by PKC-delta with PEP(taxol), a synthetic peptide encoding the taxol binding region

Beta-tubulin cDNA from the shrimp Penaeus japonicus was isolated by homology cloning. Expression of cDNA in Escherichia coli yielded a 55 kDa polypeptide, positive for monoclonal antibodies against mammalian beta-tubulin. Autoradiography demonstrated the bacterially expressed hepatopancreas beta-tubulin of P. japonicus is specifically phosphorylated by the delta isoenzyme of protein kinase C (PKC-delta) purified from the plasma membrane of the shrimp heart, in the presence of the receptor for activated PKC (RACK), but not in its absence. Purified shrimp heart PKC-delta is able to phosphorylate bacterially expressed shrimp beta-tubulin without the presence of Ca(++), but requires Mg(++). The kinase activity of purified PKC-delta on bacterially expressed beta-tubulin was enhanced by incubation with PEP(taxol), a synthetic peptide encoding the taxol-binding region of beta-tubulin. In other words, PEP(taxol) modulates the kinase activity of PKC-delta through RACK.

Taxanes in lung cancer: a review with focus on the European experience

The introduction of new agents in the treatment of lung cancer raised in the past few years new interest in clinical research on this topic. The use of taxanes as paclitaxel and docetaxel may represent a significant progress in the treatment of lung cancer. Taxanes used as single agents show a substantial activity in lung cancer and, because of their unique mechanism of action, it is possible to combine these drugs with other non-cross-resistant agents. Taxanes share a radiosensitizing effect and their use with concurrent radiotherapy appears to become a new standard. This review will focus on the European clinical experience in the treatment of lung cancer with the two compounds.

Effects of docetaxel in combination with radiation on human head and neck cancer cells (ZMK-1) and cervical squamous cell carcinoma cells (CaSki )

The purpose of this study was to determine, as we did for paclitaxel, the cytotoxic and radiosensitizing potential of docetaxel in human head and neck cancer cells (ZMK-1), and in cervical squamous cell carcinoma cells (CaSki). ZMK-1 cells were incubated with docetaxel for 3, 9 or 24 hr before irradiation and 24 hr after irradiation. CaSki cells were incubated with docetaxel 24 hr before and after irradiation. For ZMK-1 cells, the docetaxel concentrations (0.7, 0.7 and 0.35 nM) were determined to obtain approximately equivalent cell survival at the different incubation times (3, 9 and 24 hr, respectively). For CaSki cells, the necessary concentration of docetaxel was 0.07 nM. Radiation doses were given from 0 to 7 Gy. Cell survival was measured by a standard clonogenic assay after a 9-day incubation. Flow cytometry was used to measure the capacity of docetaxel to accumulate cells in the G2/M phase of the cell cycle. We observed a weak accumulation of cells in the G2/M phase for the ZMK-1 cells and a pronounced accumulation for CaSki cells. For docetaxel incubation before irradiation, the isoeffect enhancement ratios for ZMK-1 cells determined at the 37% survival level were 1.18, 2.01, and 2.40 for pre-incubation at 3, 9 and 24 hr, respectively; for CaSki cells the ratio was 1.44. For a docetaxel incubation of 24 hr after irradiation, the isoeffect enhancement ratios determined at the 37% survival level were 1.54 and 1.17 for the ZMK-1, and CaSki cells, respectively. A radiosensitizing effect of docetaxel could be demonstrated unambiguously in the two cell lines used. In contrast to our previously published results with paclitaxel, docetaxel seems to be a better radiosensitizer than paclitaxel.