A Comprehensive Review of Taxane Treatment in Breast Cancer: Clinical Perspectives and Toxicity Profiles

Taxanes, such as paclitaxel and docetaxel, have transformed the landscape of breast cancer treatment, playing pivotal roles in chemotherapy protocols for both early-stage and advanced/metastatic diseases. While these agents have demonstrated remarkable efficacy in enhancing patient outcomes, they are also linked to a range of adverse effects that can impact treatment tolerability and quality of life. This comprehensive review offers an in-depth exploration of taxane therapy in breast cancer, with a focus on clinical perspectives and toxicity profiles. We delineate the mechanisms of action of taxanes, their clinical effectiveness across various breast cancer subtypes, and the prevalent adverse effects encountered in clinical practice. Moreover, we deliberate on strategies for mitigating taxane-associated toxicity and optimizing treatment selection and sequencing based on individual patient characteristics and therapeutic objectives. Finally, we underscore areas for future research and advancement, encompassing the development of novel formulations, the identification of predictive biomarkers for treatment response, and the exploration of combination therapies to bolster therapeutic outcomes. By amalgamating existing evidence and clinical insights, this review aims to apprise clinicians and researchers of the current status of taxane treatment in breast cancer and steer endeavors toward further enhancing patient care and outcomes.

Bevacizumab-induced proteinuria and its association with antihypertensive drugs: A retrospective cohort study using a Japanese administrative database

Proteinuria is a major side-effect of the anti-tumor drug bevacizumab, although its incidence and risk factors in the real world are still unclear. Although renin-angiotensin-aldosterone system inhibitors are used clinically to prevent proteinuria, their efficacy remains unclear. The aim of the present study was to reveal the incidence and risk factors of bevacizumab-induced proteinuria and examine the effectiveness of antihypertensive drugs in preventing proteinuria. We conducted a retrospective cohort study using the National Hospital Organization Clinical Data Archives and Medical Information Analysis Databank. Hospitalized patients who received bevacizumab between January 1, 2016, and June 30, 2019, were included. The study outcome was proteinuria within 12 months of bevacizumab administration. Patient characteristics, laboratory tests, and medications were compared between patients with and without proteinuria using multivariable logistic regression analysis. Among the 2,458 patients, 27% developed proteinuria after bevacizumab administration. Nursing dependence (odds ratio [OR], 2.40; 95% confidence interval [CI], 1.89-3.05; P<0.001) and systolic blood pressure ≥140 mmHg (OR, 1.44; 95% CI, 1.17-1.79; P<0.001) were identified as risk factors. Patients with an estimated glomerular filtration rate (eGFR) of 60-89, 45-59, and <45 mL/min/1.73 m2 had 29.7%, 76.8%, and 66.0% higher odds of proteinuria, respectively, than those with an eGFR ≥90 mL/min/1.73 m2. No significant relationship was observed between antihypertensive drugs and the occurrence of proteinuria. More patients may suffer from proteinuria after bevacizumab administration than previously reported. Nursing dependence and systolic blood pressure are predictive risk factors for bevacizumab-induced proteinuria. Patients at risk of proteinuria should be closely monitored.

Use of paclitaxel carried in lipid core nanoparticles in patients with late-stage solid cancers with bone metastases: Lack of toxicity and therapeutic benefits

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LDE-PTX at 175 mg/m²/3wk dose was devoid of toxicity at > 3rd line treatment.

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Among 18 LDE-PTX treated patients, 9 had PFS > 6 months and 2 had PFS > 1 yr.

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LDE-PTX diminished bone pain and improved quality of life in all treated patients.

^{Patients with heavily pretreated, late-stage cancer and bone metastasis are usually poor candidates for further chemotherapy. Previously, we showed that association to lipid nanoparticles (LDE) drastically decreases the toxicity of anti-cancer drugs. Here, we tested the hypothesis that paclitaxel (PTX) carried in LDE could benefit end-of-life patients with painful bone metastases that had been previously treated with conventional PTX. Methods: Eighteen consecutive patients with late-stage cancer, 8 with breast, 5 with prostate and 5 with lung carcinoma, aged 59±9 years, were included in this study. All were receiving opioid medication. LDE-PTX was administered at 175 mg/m 2 every 3 weeks until disease progression. Clinical imaging examinations and serum biochemistry determinations were performed to monitor disease progression. Intensity of bone pain, use of opioid medications and occurrence of pathological bone fractures were also evaluated. Results: In total, 104 chemotherapy cycles were performed and none of the patients showed clinical and laboratorial toxicities or pathological bone fractures. In all patients, pain was reduced so as to allow substitution of non-opioid for opioid medication. Median progression-free survival (PFS) was four months (95% CI 2.4-5.5), but in five patients PFS was longer than 6 months. Conclusions: Absence of observable clinical and laboratorial toxicities from LDE-PTX treatment, improvement of bone pain and the possible effect on PFS in some patients, despite previous use of conventional PTX, suggest that LDEPTX merits further clinical investigation.}

A Phase I Study of an MPS1 Inhibitor (BAY 1217389) in Combination with Paclitaxel Using a Novel Randomized Continual Reassessment Method for Dose Escalation

PURPOSE

Monopolar spindle 1 (MPS1) kinase inhibitor, BAY 1217389 (BAY) synergizes with paclitaxel. This phase I study assessed the combination of BAY with paclitaxel using a novel randomized continuous reassessment method (rCRM) to improve dose determination.

PATIENTS AND METHODS

Patients with solid tumors were randomized to receive oral BAY (twice daily 2-days-on/5-days-off) with weekly paclitaxel (90 mg/m²) or paclitaxel monotherapy in cycle 1. Dose escalation was guided by CRM modeling. Primary objectives were to assess safety, establish the MTD of BAY, and to evaluate the pharmacokinetic profiles for both compounds. Simulations were performed to determine the contribution of the rCRM for dose determination.

RESULTS

In total, 75 patients were enrolled. The main dose-limiting toxicities were hematologic toxicities (55.6%). The MTD of BAY was established at 64 mg twice daily with paclitaxel. Inclusion of a control arm enabled the definitive attribution of grade ≥3 neutropenia to higher BAY exposure [AUC_0-12 (P< 0.001)]. After determining the MTD, we included 19 patients with breast cancer at this dose for dose expansion. Other common toxicities were nausea (45.3%), fatigue (41.3%), and diarrhea (40.0%). Overall confirmed responses were seen in 31.6% of evaluable patients. Simulations showed that rCRM outperforms traditional designs in determining the true MTD.

CONCLUSIONS

The combination of BAY with paclitaxel was associated with considerable toxicity without a therapeutic window. However, the use of the rCRM design enabled us to determine the exposure-toxicity relation for BAY. Therefore, we propose that the rCRM could improve dose determination in phase I trials that combine agents with overlapping toxicities.

Nanopaclitaxel therapy: an evidence based review on the battle for next-generation formulation challenges

The poor solubility of paclitaxel (PTX), the most commonly used anticancer drug (Taxol^®), has long hindered the development of successful formulations. In 2005, the launch of Abraxane^®, a human albumin-based preparation of PTX, competed with Taxol^® in the commercial market. The success of Abraxane pushed other generic preparations aside, sparking competition among the global pharmaceutical companies to develop the novel and superior PTX nanotechnology-driven formulations. Unsurprisingly, the success underlying with cancer treatment using nano PTX therapy has now entered into a new era of drug development, patentability, preclinical and clinical evaluation, leading eventually to a significant increase in the regulatory approval of the products. The present article aims to provide recent progress in the development of nano PTX formulations by various pharmaceutical companies for safe and effective drug therapies for patients benefit.

Safety and Efficacy of Docetaxel, Bevacizumab, and Everolimus for Castration-resistant Prostate Cancer (CRPC)

BACKGROUND

Previous data suggests that co-targeting mammalian target of rapamycin and angiogenic pathways may potentiate effects of cytotoxic chemotherapy. We studied combining mammalian target of rapamycin and vascular endothelial growth factor inhibition with docetaxel in castrate-resistant prostate cancer (CRPC).

METHODS

Eligible patients had progressive, metastatic, chemotherapy-naive CRPC. Docetaxel and bevacizumab were given intravenously day 1 with everolimus orally daily on a 21-day cycle across 3 dose levels (75:15:2.5, 75:15:5, and 65:15:5; docetaxel mg/m2, mg/kg bevacizumab, and mg everolimus, respectively). Maintenance therapy with bevacizumab/everolimus without docetaxel was allowed after ≥ 6 cycles.

RESULTS

Forty-three subjects were treated across all dose levels. Maximal tolerated doses for the combined therapies observed in the phase 1B portion of the trial were: docetaxel 75 mg/m2, bevacizumab 15 mg/kg, and everolimus 2.5 mg. Maximal prostate-specific antigen decline ≥ 30% and ≥ 50% was achieved in 33 (79%) and 31 (74%) of patients, respectively. Best response by modified Response Evaluation Criteria In Solid Tumors criteria in 25 subjects with measurable disease at baseline included complete or partial response in 20 (80%) patients. The median progression-free and overall survival were 8.9 months (95% confidence interval, 7.4-10.6 months) and 21.9 months (95% confidence interval, 18.4-30.3 months), respectively. Hematologic toxicities were the most common treatment-related grade ≥ 3 adverse events including: febrile neutropenia (12; 28%), lymphopenia (12; 28%), leukocytes (10; 23%), neutrophils (9; 21%), and hemoglobin (2; 5%). Nonhematologic grade ≥ 3 adverse events included: hypertension (8; 19%), fatigue (3; 7%), pneumonia (3; 7%), and mucositis (4; 5%). There was 1 treatment-related death owing to neutropenic fever and pneumonia in a patient treated at dose level 3 despite dose modifications and prophylactic growth factor support.

CONCLUSIONS

Docetaxel, bevacizumab, and everolimus can be safely administered in CRPC and demonstrate a significant level of anticancer activity, meeting the predetermined response criteria. However, any potential benefit of combined therapy must be balanced against increased risk for toxicities. Our results do not support the hypothesis that this combination of agents improves upon the results obtained with docetaxel monotherapy in an unselected population of chemotherapy-naive patients with CRPC.

Targeted therapies in breast cancer: New challenges to fight against resistance

Breast cancer is the most common type of cancer found in women and today represents a significant challenge to public health. With the latest breakthroughs in molecular biology and immunotherapy, very specific targeted therapies have been tailored to the specific pathophysiology of different types of breast cancers. These recent developments have contributed to a more efficient and specific treatment protocol in breast cancer patients. However, the main challenge to be further investigated still remains the emergence of therapeutic resistance mechanisms, which develop soon after the onset of therapy and need urgent attention and further elucidation. What are the recent emerging molecular resistance mechanisms in breast cancer targeted therapy and what are the best strategies to apply in order to circumvent this important obstacle? The main scope of this review is to provide a thorough update of recent developments in the field and discuss future prospects for preventing resistance mechanisms in the quest to increase overall survival of patients suffering from the disease.

Genotypes of CYP2C8 and FGD4 and their association with peripheral neuropathy or early dose reduction in paclitaxel-treated breast cancer patients

Background:

The purpose of this study was to evaluate single-nucleotide polymorphisms (SNPs) in genes encoding key metabolising enzymes or involved in pharmacodynamics for possible associations with paclitaxel-induced peripheral neuropathy.

Methods:

The study population consists of 188 women from the multicenter, randomised, phase II ATX trial (BOOG2006-06; EudraCT number 2006-006058-83) that received paclitaxel and bevacizumab without or with capecitabine as first-line palliative therapy of HER2-negative metastatic breast cancer. Genotyping of CYP2C8*3 (c.416G>A), CYP3A4*22 (c.522-191C>T), TUBB2A (c.-101T>C), FGD4 (c.2044-236G>A) and EPHA5 (c.2895G>A) was performed by real-time PCR. Toxicity endpoints were cumulative dose (1) until first onset of grade ⩾1 peripheral neuropathy and (2) until first paclitaxel dose reduction from related toxicity (NCI-CTCAE version 3.0). SNPs were evaluated using the Kaplan–Meier method, the Gehan–Breslow–Wilcoxon test and the multivariate Cox regression analysis.

Results:

The rate of grade ⩾1 peripheral neuropathy was 67% (n=126). The rate of dose reduction was 46% (n=87). Age ⩾65 years was a risk factor for peripheral neuropathy (HR=1.87, P<0.008), but not for dose reduction. When adjusted for age, body surface area and total cumulative paclitaxel dose, CYP2C8*3 carriers had an increased risk of peripheral neuropathy (HR=1.59, P=0.045). FGD4 c.2044-236 A-allele carriers had an increased risk of paclitaxel dose reduction (HR per A-allele=1.38, P=0.036) when adjusted for total cumulative paclitaxel dose.

Conclusions:

These findings may point towards clinically useful indicators of early toxicity, but warrant further investigation.

A pilot study to determine the timing and effect of bevacizumab on vascular normalization of metastatic brain tumors in breast cancer

Background

To determine the appropriate time of concomitant chemotherapy administration after antiangiogenic treatment, we investigated the timing and effect of bevacizumab administration on vascular normalization of metastatic brain tumors in breast cancer patients.

Methods

Eight patients who participated in a phase II trial for breast cancer-induced refractory brain metastases were enrolled and subjected to 4 dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) examinations that evaluated Peak, Slope, iAUC₆₀, and Ktrans before and after treatment. The treatment comprised bevacizumab on Day 1, etoposide on Days 2–4, and cisplatin on Day 2 in a 21-day cycle for a maximum of 6 cycles. DCE-MRI was performed before treatment and at 1 h, 24 h, and 21 days after bevacizumab administration.

Results

Values of the 4 DCE-MRI parameters reduced after bevacizumab administration. Compared with baseline values, the mean reductions at 1 and 24 h were −12.8 and −24.7 % for Peak, −46.6 and −65.8 % for Slope, −27.9 and −55.5 % for iAUC₆₀, and −46.6 and −63.9 % for Ktrans, respectively (all P < .05). The differences in the 1 and 24 h mean reductions were significant (all P < .05) for all the parameters. The generalized estimating equation linear regression analyses of the 4 DCE-MRI parameters revealed that vascular normalization peaked 24 h after bevacizumab administration.

Conclusion

Bevacizumab induced vascular normalization of brain metastases in humans at 1 and 24 h after administration, and the effect was significantly higher at 24 h than at 1 h.

Trial registration

ClinicalTrials.gov, identifier NCT01281696, registered prospectively on December 24, 2010

Investigation of antitumor effects of sorafenib and lapatinib alone and in combination on MCF-7 breast cancer cells

BACKGROUND

Breast cancer evolution and tumor progression are controlled by complex interactions between steroid receptors and growth factor receptor signaling. Aberrant growth factor receptor signaling can augment or suppress estrogen receptor function in hormone-dependent breast cancer cells. Thus, we aimed to investigate antitumor effects of sorafenib and lapatinib alone and in combination on MCF-7 breast cancer cells.

MATERIALS AND METHODS

Cytotoxicity of the sorafenib and lapatinib was tested in MCF-7 cells by XTT assays. 50, 25, 12.5 and 6.25μM concentrations of sorafenib and 200, 100, 50 and 25μM concentrations of lapatinib were administered alone and in combination. Results were evaluated as absorbance at 450nM and IC50 values are calculated according to the absorbance data

RESULTS

Both sorafenib and lapatinib showed concentration dependent cytotoxic effects on MCF-7 cells. Sorafenib exerted cytotoxic effects with an IC50 value of 32.0μM; in contrast with lapatinib the IC50 was 136.6μM. When sorafenib and lapatinib combined, lapatinib increased cytotoxic effects of sorafenib at its ineffective concentrations. Also at the concentrations where both drugs had cytotoxic effects, combination show strong anticancer effects and killed approximately 70 percent of breast cancer cells.

CONCLUSIONS

Combinations of tyrosine kinase inhibitors and cytotoxic agents or molecular targeted therapy has been successful for many types of cancer. The present study shows that both sorafenib and lapatinib alone are effective in the treatment of breast cancer. Also a combination of these two agents may be a promising therapeutic option in treatment of breast cancer.

Nab-paclitaxel/bevacizumab/carboplatin chemotherapy in first-line triple negative metastatic breast cancer

BACKGROUND

Triple negative metastatic breast cancer can be difficult to treat with primarily cytotoxic options. Nab-paclitaxel has demonstrated improved PFS and tolerability compared with standard cremophor-solubilized paclitaxel; based on this, we examined the efficacy and safety of combining weekly nab-paclitaxel with carboplatin and bevacizumab in TNMBC.

PATIENTS AND METHODS

In this phase II, multicenter trial, patients with first-line TNMBC received nab-paclitaxel (100 mg/m(2)) and carboplatin (area under the curve = 2) on days 1, 8, 15, and bevacizumab (10 mg/kg) on days 1 and 15 of a 28-day cycle. The primary end point was safety and tolerability and secondary end points included PFS, ORR, and CBR. PFS was calculated using the Kaplan-Meier method.

RESULTS

Between July 16, 2007, and October 3, 2011, 34 patients were enrolled at 4 centers. Median age was 50.0 (range, 30-76) years and 77% (n = 26) of patients received previous adjuvant therapy. Median PFS was 9.2 months (95% confidence interval [CI], 7.8-25.1 months). The CBR was 94% (95% CI, 80%-99%), and ORR was 85% (95% CI, 69%-95%) for the combination. The regimen was well tolerated with the most common grade 3/4 adverse events being neutropenia (n = 18; 53%) and thrombocytopenia (n = 6; 18%), with other serous events including 1 grade 3 and 1 grade 4 thrombotic event and 1 febrile neutropenia.

CONCLUSION

The combination of nab-paclitaxel, bevacizumab, and carboplatin as first-line treatment for TNMBC was efficacious and well tolerated. The PFS, CBR, and ORR, and tolerability of the regimen, compares favorably with other standard first-line therapies.

Neoadjuvant bevacizumab: surgical complications of mastectomy with and without reconstruction

Neoadjuvant therapy (NAC) is commonly used in operable breast cancer. Previous studies have suggested a high rate of postoperative complications after NAC. We prospectively evaluated the surgical complications in a cohort of patients who underwent mastectomy following neoadjuvant adriamycin/cytoxan/taxol (AC/T) plus bevacizumab (bev) and compared the rate of complications to a matched cohort of neoadjuvant AC/T without bev. One hundred patients with HER2-negative breast cancer enrolled in a single-arm trial of neoadjuvant AC/T plus bev (cohort 1), 60 of these patients underwent mastectomy and were matched with 59 patients who received standard neoadjuvant AC/T (cohort 2) over a similar time period in the same healthcare system. All patients underwent mastectomy with or without reconstruction. Fisher's exact tests were used to compare complication rates, with p < 0.05 considered significant. Patients were matched well in terms of demographics. The overall complication rate was 32 % in cohort 1 and 31 % in cohort 2 (p value = 1, Table 1). In cohort 1, 7 of 23 (30 %) patients who underwent immediate expander/implant reconstruction had complications, including 2 patients who had explantation of their reconstructions. In cohort 2, 0 of 8 (0 %) had complications (p value = 0.15). Nearly a third of patients undergoing NAC with AC/T with or without bev developed a postoperative complication after mastectomy. The use of bev was not associated with a significant increase in surgical complications, although this is a nonrandomized data set with a small sample size. As larger data sets become available with the use of neoadjuvant bevacizumab with mastectomy, further refinement may be necessary.

Anti-Neoplastic Cytotoxicity of Gemcitabine-(C4-amide)-[anti-HER2/neu] in Combination with Griseofulvin against Chemotherapeutic-Resistant Mammary Adenocarcinoma (SKBr-3)

Introduction

Gemcitabine is a pyrimidine nucleoside analog that becomes triphosphorylated and in this form it competitively inhibits cytidine incorporation into DNA strands. Diphosphorylated gemcitabine irreversibly inhibits ribonucleotide reductase thereby preventing deoxyribonucleotide synthesis. Functioning as a potent chemotherapeutic, gemcitabine decreases neoplastic cell proliferation and induces apoptosis which accounts for its effectiveness in the clinical treatment of several leukemia and carcinoma cell types. A brief plasma half-life due to rapid deamination, chemotherapeuticresistance and sequelae restricts gemcitabine utility in clinical oncology. Selective “targeted” gemcitabine delivery represents a molecular strategy for prolonging its plasma half-life and minimizing innocent tissue/organ exposure.

Methods

A previously described organic chemistry scheme was applied to synthesize a UV-photoactivated gemcitabine intermediate for production of gemcitabine-(C₄-amide)-[anti-HER2/neu]. Immunodetection analysis (Western-blot) was applied to detect the presence of any degradative fragmentation or polymerization. Detection of retained binding-avidity for gemcitabine-(C₄-amide)-[anti-HER2/neu] was determined by cell-ELISA using populations of chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) that highly over-express the HER2/neu trophic membrane receptor. Anti-neoplastic cytotoxicity of gemcitabine-(C₄-amide)-[anti-HER2/neu] and the tubulin/microtubule inhibitor, griseofulvin was established against chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3). Related investigations evaluated the potential for gemcitabine-(C₄-amide)-[anti-HER2/neu] in dual combination with griseofulvin to evoke increased levels of anti-neoplastic cytotoxicity compared to gemcitabine-(C₄-amide)-[anti-HER2/neu].

Results

Covalent gemcitabine-(C₄-amide)-[anti-HER2/neu] immunochemotherapeutic and griseofulvin exerted anti-neoplastic cytotoxicity against chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3). Covalent gemcitabine-(C₄-amide)-[anti-HER2/neu] immunochemotherapeutic or gemcitabine in dual combination with griseofulvin created increased levels of anti-neoplastic cytotoxicity that were greater than was attainable with gemcitabine-(C₄-amide)-[anti-HER2/neu] or gemcitabine alone.

Conclusion

Gemcitabine-(C₄-amide)-[anti-HER2/neu] in dual combination with griseofulvin can produce enhanced levels of anti-neoplastic cytotoxicity and potentially provide a basis for treatment regimens with a wider margin-of-safety. Such benefits would be possible through the collective properties of; [i] selective “targeted” gemcitabine delivery; [ii] relatively lower toxicity of griseofulvin compared to many if not most conventional chemotherapeutics; [iii] reduced total dosage requirements faciliated by additive or synergistic anti-cancer properties; and [iv] differences in sequelae for gemcitabine-(C₄-amide)-[anti-HER2/neu] compared to griseofulvin functioning as a tubulin/microtubule inhibitor.

The impact of Bevacizumab (Avastin) on survival in metastatic solid tumors--a meta-analysis and systematic review

Purpose

To evaluate the effect of Bevacizumab in combination with chemotherapy on overall survival of patients with metastatic solid tumors.

Design

A systematic literature search to identify randomized trials comparing chemotherapy with and without Bevacizumab in metastatic cancer. The primary end point was overall survival (OS) and the secondary end points were progression free survival (PFS) and toxicity. A meta-analysis was performed for each tumor type and for the combination of all tumors.

Results

24 randomized trials with 8 different types of malignancies were included in this meta-analysis. Patients treated with Bevacizumab had an OS benefit, hazard ratio (HR) 0.89 (95% CI 0.84–0.93, P<0.00001 I²-4%). The combined analysis showed a PFS benefit with a HR 0.71 (95% CI 0.68–0.74, P<0.00001, I²-54%). The toxicity analysis showed a statistically significant increase in fatal adverse events (FAEs) in the Bevacizumab treatment arm, risk ratio (RR) 1.47 (95% CI 1.1–1.98). A separate analysis of the lung cancer trials showed an increased risk of fatal pulmonary hemorrhage with a RR of 5.65 (95% CI 1.26–25.26). The risk of G3–4 adverse events was increased: RR 1.2 (95% CI 1.15–1.24).

Conclusion

in this combined analysis Bevacizumab improved OS (with little heterogeneity) and PFS. These results should be considered in the light of lack of markers predictive of response and the increased severe and fatal toxicity seen with Bevacizumab treatment.

Paclitaxel and bevacizumab in first-line treatment for HER2-negative metastatic breast cancer: single-center experience

The aim of our analysis was to report the outcome and safety of patients treated with bevacizumab and paclitaxel as first-line treatment for HER2-negative metastatic breast cancer. Between February 2009 and August 2011, 62 consecutive patients received paclitaxel 90 mg/m(2) on days 1, 8, and 15 and bevacizumab (BV) 10 mg/kg intravenously on days 1 and 15, every 28-day cycle. After 6 cycles of combined treatment, patients were given maintenance BV every 3 weeks (15 mg/kg) until progression disease or unacceptable toxicity. At time of analysis, median overall survival was 12.3 months (range 4.6-44.8 months), progression-free survival was 8.1 months (range 2.3-33.2 months), and time to treatment failure was 8.4 months (range 2.3-33.2 months). Our results confirmed the efficacy and the acceptable toxicity profile of bevacizumab plus paclitaxel as first-line regimen for metastatic breast cancer.

Influence of Alternative Tubulin Inhibitors on the Potency of a Epirubicin-Immunochemotherapeutic Synthesized with an Ultra Violet Light-Activated Intermediate: Influence of incorporating an internal/integral disulfide bond structure and Alternative Tubulin/Microtubule Inhibitors on the Cytotoxic Anti-Neoplastic Potency of Epirubicin-(C3-amide)-Anti-HER2/neu Synthesized Utilizing a UV-Photoactivated Anthracycline Intermediate

Immunochemotherapeutics, epirubicin-(C₃-amide)-SS-[anti-HER2/neu] with an internal disulfide bond, and epirubicin-(C₃-amide)-[anti-HER2/neu] were synthesized utilizing succinimidyl 2-[(4,4'-azipentanamido) ethyl]-1,3'-dithioproprionate or succinimidyl 4,4-azipentanoate respectively. Western blot analysis was used to determine the presence of any immunoglobulin fragmentation or IgG-IgG polymerization. Retained HER2/neu binding characteristics of epirubicin-(C₃-amide)-[anti-HER2/neu] and epirubicin-(C₃-amide)-SS-[anti-HER2/neu] were validated by cell-ELISA using a mammary adenocarcinoma (SKBr-3) population that highly over-expresses trophic HER2/neu receptor complexes. Cytotoxic anti-neoplastic potency of epirubicin-(C₃-amide)-[anti-HER2/neu] and epirubicin-(C₃-amide)-SS-[anti-HER2/neu] between epirubicin-equivalent concentrations of 10^-10 M and 10^-6 M was determined by measuring the vitality/proliferation of chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3 cell type). Cytotoxic anti-neoplastic potency of benzimidazoles (albendazole, flubendazole, membendazole) and griseofulvin were assessed between 0-to-2 μg/ml and 0-to-100 μg/ml respectively while mebendazole and griseofulvin were analyzed at fixed concentrations of 0.35 μg/ml and 35 g/ml respectively in dual combination with gradient concentrations of epirubicin-(C₃-amide)-[anti-HER2/neu] and epirubicin-(C₃-amide)-SS-[anti-HER2/neu]. Cytotoxic anti-neoplastic potency for epirubicin-(C₃-amide)-[anti-HER2/neu] and epirubicin-(C₃-amide)-SS-[anti-HER2/neu] against chemotherapeutic-resistant mammary adenocarcinoma (SKBr-3) was nearly identical at epirubicin-equivalent concentrations of 10^-10 M and 10^-6 M. The benzimadazoles also possessed cytotoxic anti-neoplastic activity with flubendazole and albendazole being the most and least potent respectively. Similarly, griseofulvin had cytotoxic anti-neoplastic activity and was more potent than methylselenocysteine. Both mebendazole and griseofulvin when applied in dual combination with either epirubicin-(C₃-amide)-[anti-HER2/neu] or epirubicin-(C₃-amide)-SS-[anti-HER2/neu] produced enhanced levels of cytotoxic anti-neoplatic potency.

Maintenance bevacizumab beyond first-line paclitaxel plus bevacizumab in patients with Her2-negative hormone receptor-positive metastatic breast cancer: efficacy in combination with hormonal therapy

Background

Data on efficacy of bevacizumab (B) beyond first-line taxane -including regimen (BT) as first-line treatment are lacking. Although preclinical results that anti-angiogenic agents combined with hormonal therapy (HT) could be active, no clinical data exist about combination of maintenance Bevacizumab (mBev) with HT.

Methods

Thirty-five patients who experienced a response after first-line BT, were given mBev at the dose of 15 mg/kg every 3 weeks. Among 30 pts with hormonal receptor-positive metastatic breast cancer (MBC), 20 (66.6%) received HT with mBev (mHTBev). Objective of the study was the outcome and safety of mBev and in two groups of patients receiving HT or not.

Results

Complete response and partial response was achieved/maintained in 4 (11.4%) and 13 (37.1%) patients, respectively (overall response rate: 48.5%). Clinical benefit was obtained on 23 patients (65.7%). Median of mBev PFS and clinical benefit were 6.8 months (95% CI: 0.8-12.7) and 17.1 months (95% CI :12.2-21.9), respectively. Median PFS of patients who received mHTBev was longer than mBev without HT (13 months and 4.1 months, respectively, p = 0.05). The most common severe toxicities were proteinuria (11.4%) and hypertension (8.5%). No additional toxicity was observed with HTBev.

Conclusion

Maintenance bevacizumab with or without anti-hormonal therapy in patients with hormone receptor positive breast cancer is tolerable and associated with long-term clinical outcome; these results encourage the strategy of prolonging bevacizumab until progression in combination with anti-hormonal agents.

Critical issues on high-dose chemotherapy with autologous hematopoietic progenitor cell transplantation in breast cancer patients

INTRODUCTION

High-dose chemotherapy (HDC) with autologous hematopoietic progenitor cell transplantation (AHPCT) for high-risk (HR) or metastatic breast cancer (MBC) is no longer an option.

AREAS COVERED

An expert panel including medical oncologists and hematologists produce an opinion paper on the use of HDC and AHPCT in BC patients and they explain why they believe that; despite inconclusive results thus far, this treatment should have an ongoing role in breast cancer management under clinical trials.

EXPERT OPINION

HDC with AHPCT has become a safe treatment modality and an advantage in disease-free survival has been observed in most of the studies with HDC, with the caveat that today, even a limited relapse-free survival and progression-free survival benefit is sufficient for the approval of new antineoplastic agents. Moreover, in HRBC, an overall survival benefit by HDC could be achieved in the HER2-ve and triple-negative populations and, in this setting, HDC with AHPCT represents a therapeutic option that can be proposed to well-informed patients. In MBC, the HDC approach should be investigated further in selected patients with HER2-ve, chemosensitive disease. This paper is not intended to give any conclusion, but rather to open a debate on the value of HDC in HR and MBC.

Mechanisms of Resistance to Trastuzumab and Novel Therapeutic Strategies in HER2-Positive Breast Cancer

HER2-positive breast cancers have poorer prognosis and are prime candidates for molecular-targeted therapy because they are driven by the unique mechanism of HER2 oncogene addiction. While anti-HER2 agents such as trastuzumab and lapatinib are integral to the treatment of HER2-positive breast cancer, intrinsic and secondary resistance pose a significant challenge, underscoring the need to develop novel anti-HER2 therapies. In recent years, an array of promising and novel anti-HER2 therapeutic agents and their combinations have entered various stages of clinical development. However, questions remain on the optimal sequences of HER2-directed therapies and selection of patients for the most appropriate drug or combinations; incompletely defined mechanisms of trastuzumab action and resistance have also dampened the progress of more successful biomarker-driven treatment approaches. This paper summarizes existing preclinical and clinical evidence on the mechanisms of trastuzumab action and resistance and provides an up-to-date overview of novel HER2-directed therapies in clinical development.

Benefit-risk assessment of bevacizumab in the treatment of breast cancer

An evaluation of the benefit-versus-risk of bevacizumab in the treatment of advanced breast cancer is timely and relevant. Recently, the US FDA has withdrawn the approval of bevacizumab as a therapeutic option for the treatment of advanced breast cancer, generating controversy in the scientific community. Although the pivotal study (Eastern Cooperative Oncology Group 2100 trial [E2100]) had shown doubling of the progression-free survival when bevacizumab was added to chemotherapy, this magnitude of benefit could not be replicated in subsequent studies. Furthermore, individual studies and meta-analyses failed to demonstrate an overall survival benefit with the addition of bevacizumab to different chemotherapy regimens. In addition, this agent is associated with an increased incidence of serious adverse events such as hypertension, congestive heart failure and thromboembolism, and its cost is likely to be a consideration in its use for many patients worldwide. Retrospective biomarker-based studies aiming to identify the subpopulation of patients most likely to benefit from the addition of bevacizumab to standard chemotherapy in breast cancer should be a research priority.

Combined-modality radioimmunotherapy: synergistic effect of paclitaxel and additive effect of bevacizumab

INTRODUCTION

This study was undertaken to investigate the effect of paclitaxel and bevacizumab on the therapeutic efficacy of (90)Y-labeled B3 monoclonal antibody, directed against Le(y) antigen, for the treatment of Le(y)-positive A431 tumors implanted subcutaneously in the right hind flank of nude mice.

METHODS

When the tumor size reached ~200 mm(3), the mice received a single dose of intravenous (iv) (90)Y-labeled B3 (60 μCi/150 μg or 100 μCi/150 μg B3), intraperitoneal paclitaxel (40 mg/kg) or iv bevacizumab (5 mg/kg) for monotherapy. To investigate the effect of combined therapies on survival, the mice were treated with two or three agents in the following combinations: (90)Y-B3 on day 0 and paclitaxel on day 1; bevacizumab on -1 day and (90)Y-B3 on day 0; bevacizumab on -1 day and paclitaxel on day 1; bevacizumab, (90)Y-B3 and paclitaxel each at 1-day intervals. The mice with no treatment were used as a control. The tumor volume at 1000 mm(3) was used as a surrogate end point of survival.

RESULTS

Compared to control animals, paclitaxel delayed tumor growth with a significantly longer median survival time (P<.001), whereas bevacizumab alone showed a less pronounced effect on a median survival time (P=.18). (90)Y-B3 increased the median survival time in a dose-dependent manner (P<.05). The combined therapy of bevacizumab with paclitaxel produced a trend toward an increase of the median survival time compared to paclitaxel alone (P=.06), whereas bevacizumab combined with (90)Y-B3 showed a statistically insignificant increase in the median survival time compared to (90)Y-B3 alone (P=.25). The tumor sizes of all animals in these groups reached the surrogate end point of survival by day 35. In contrast, the combined therapy involving (90)Y-B3 with paclitaxel showed a striking synergistic effect in shrinking tumors and prolonging the survival time (P<.001); on day 120, three of nine mice (33%) and six of six mice (100%) were alive without tumor when treated with 60 μCi (90)Y-B3 and 100 μCi (90)Y-B3, respectively. The addition of bevacizumab treatment 1 day before the combined therapy of 60 μCi (90)Y-B3 with paclitaxel did not produce a statistically significant increase in survival when compared to the (90)Y-B3 with paclitaxel (P>.10). Fluorescence microscopy analysis indicated that paclitaxel increased, whereas bevacizumab decreased, the accumulation and penetration of Alexa Fluor 647-B3 into tumor microenvironment compared to the control (P<.05).

CONCLUSION

Our findings on the paclitaxel effect support a hypothesis that the increased tumor accumulation and penetration of (90)Y-B3 as well as the high radiosensitization of tumor cells by paclitaxel may be the major factors responsible for the synergistic effect of the combined therapy involving (90)Y-B3 with paclitaxel.

Chemoprevention in colorectal cancer--where we stand and what we have learned from twenty year's experience

INTRODUCTION

Colorectal chemoprevention is a strategy aimed at preventing tumour progression before irreversible changes to the proteome are in full progress. Chemoprevention is not a new concept. In fact, medical practitioners since the early 19th century have tried various herbal and medicinal products as methods that could prevent tumours. The current understanding of tumourigenesis and cellular signalling focuses on a more targeted approach and paves the way for better understanding of colorectal chemoprevention.

METHODS

The online databases PubMed, Medline, Medscape Oncology and Scirrus were searched for articles of relevance. The Keyword involved the following words: "Colorectal Cancer Chemoprevention", "Colorectal Cancer", "Chemoprevention", "Adenoma-Carcinoma Sequence" and "Colorectal Polyps". The search was started from the period of June 1995 until September 2010 inclusive.

RESULTS

More than 50 natural and synthetic compounds have been shown to have chemotherapeutic effect but the majority of these agents are still in their early experimental stages and hence far from our subject of discussion. Our discussion will focus on large scale randomised trials on human subjects or established compounds. Within the context of chemoprevention, Non-steroidal anti-inflammatory agents have undergone extensive research and have shown promising results with large scale randomised trials. Additionally, metformin, resveratrol, Histone deacetylase inhibitors, Src kinases as well monoclonal antibodies have shown promising results as well.

CONCLUSION

Colorectal cancer is the fourth most common cancer in the world. In the UK alone the number of cases reported in 2008 was almost 40,000 which make it the third most common tumour nationwide. Curative intent surgery or Colectomy is the treatment of choice for most cases of bowel cancer; however, in a select subpopulation of patients who have been colonoscopically diagnosed to harbour pre-malignant lesions, have a family history of colorectal cancer, or have been genetically diagnosed and treated surgically for colorectal tumours; chemoprevention might play a crucial role in deterring further tumour progression. The very latest studies that are in publication or are just accruing results are giving us encouraging data that might suggest whether mass scale ingestion of a specific medication might deter colorectal tumour progression.

Efficacy and safety of bevacizumab in combination with docetaxel for the first-line treatment of elderly patients with locally recurrent or metastatic breast cancer: results from AVADO

BACKGROUND

Oncologic treatment in elderly patients is challenging, due to comorbidities, often impaired organ function, limited clinical trial evidence, inadequate guidelines and no consistent 'elderly' definition. We report exploratory sub-analyses of safety and efficacy in elderly patients, defined as ⩾ 65years old, in AVastin And DOcetaxel (AVADO) receiving first-line bevacizumab plus docetaxel for metastatic breast cancer (mBC).

PATIENTS AND METHODS

Patients with HER2-negative, locally recurrent or mBC were randomised to 3-weekly docetaxel (100mg/m(2)) with placebo, bevacizumab 7.5mg/kg or bevacizumab 15 mg/kg, for 9 cycles or until disease progression or unacceptable toxicity. Patients had no prior chemotherapy for mBC.

RESULTS

Progression-free survival (PFS) was increased with bevacizumab in the elderly subpopulation (n=127), the effect being greater with higher dose (hazard ratio=0.63 [95% confidence interval (CI) 0.383-1.032] versus 0.76 [95% CI: 0.46-1.262], respectively). PFS was numerically similar in the elderly and overall populations, but the former failed to achieve statistical significance. Overall response rates for docetaxel plus placebo, bevacizumab 7.5mg/kg and 15 mg/kg were 44.7%, 36.6% and 50.0%, respectively. Effects on survival were not statistically significant. Bevacizumab was well tolerated in elderly patients, the most common adverse effects were neutropenia and febrile neutropenia; there was no excess of grade⩾3 cardiovascular events. There was no clear correlation between baseline hypertension and its development during study treatment.

CONCLUSIONS

In this exploratory sub-analysis in AVADO, bevacizumab plus docetaxel showed efficacy in elderly patients similar to the overall study population. There were no unexpected safety signals in patients aged 65 years or older.

Biologically targeted cancer therapy and marginal benefits: are we making too much of too little or are we achieving too little by giving too much?

We describe the development and approval of biologically targeted agents in the clinic through examples chosen from the experience with inhibitors of the epidermal growth factor (EGF) and VEGF pathways. Despite extensive biological rationale for the use of these classes of molecules, marginal clinical benefits have been observed in broad patient populations, and the agents have entered into general clinical practice. We discuss why this situation is unsatisfactory because marginal general benefit may often be at the expense of toxicity to nonbenefiting or even harmed patients. Finally, we point out that emerging technologies bring the promise of allowing the identification of patients who might potentially benefit from a therapy. However, development of this technology will not move forward without broader recognition of its need by the range of stakeholders, including patients, advocates, academic and private oncologists, drug sponsors, and those who develop drugs and diagnostic tests.

Treatment options for patients with triple-negative breast cancer

Breast cancer is a heterogeneous disease composed of different subtypes, characterized by their different clinicopathological characteristics, prognoses and responses to treatment. In the past decade, significant advances have been made in the treatment of breast cancer sensitive to hormonal treatments, as well as in patients whose malignant cells overexpress or amplify HER2. In contrast, mainly due to the lack of molecular targets, little progress has been made in the treatment of patients with triple-negative breast cancer. Recent improved understanding of the natural history, pathophysiology, and molecular features of triple-negative breast cancers have provided new insights into management and therapeutic strategies for women affected with this entity. Ongoing and planned translational clinical trials are likely to optimize and improve treatment of women with this disease.

Through a glass darkly: advances in understanding breast cancer biology, 2000-2010

Our understanding of breast cancer as a clinical and biologic entity has been gaining granularity for several decades; in particular, the importance of hormone receptors and HER2 were realized long ago and have served as the impetus for therapeutic agents that have improved the cure rate of estrogen receptor-positive and HER2-positive breast cancer and the lives of thousands of women. The past decade brought even more understanding of the complexity of breast cancer biology through the development and clinical applications of array-based technologies for discovery and prognostication. We now realize that there are at least 5 intrinsic subtypes within breast cancer, at least one of which-the basal-like-currently lacks targeted therapies and is the most pressing therapeutic challenge for the next decade. We have several validated prognostic profiles that allow increased thoughtfulness in adjuvant decision making. With this understanding also comes the recognition that if breast cancer represents several biologically distinct entities, then breast cancer risk assessment and treatment must take this heterogeneity into account, which complicates trial design and interpretation. Despite therapeutic advances and the development of a number of targeted agents against hormone receptor signaling, HER2, and angiogenesis, we have significant challenges to overcome. These include the need for more tissue-based studies to allow us to understand the mechanisms of sensitivity and resistance within and across subtypes, and the need to revisit risk and prevention by subtype.