Pegylated liposomal doxorubicin (Lipo-Dox®) combined with cyclophosphamide and 5-fluorouracil is effective and safe as salvage chemotherapy in taxane-treated metastatic breast cancer: an open-label, multi-center, non-comparative phase II study

Thirty years from FDA approval of pegylated liposomal doxorubicin (Doxil/Caelyx): an updated analysis and future perspective

In 2025, it will be 30 years since the initial clinical approval of pegylated liposomal doxorubicin (PLD) by the Food and Drug Administration. PLD predated the field of nanomedicine and became a model nanomedicine setting key pharmacological principles (prolonged circulation, slow drug release and the enhanced permeability and retention (EPR) effect) for clinical application of other nano-drugs in cancer therapy. The impressive reduction of cardiotoxicity conferred by PLD is the most valuable clinical asset. While PLD has gained a strong foothold in relapsed ovarian cancer and metastatic breast cancer, it has not been extensively tested in primary (neoadjuvant) and adjuvant therapy and has not fulfilled the expectations from the results in animal models efficacy-wise. This discrepancy may be due to the large dose gap between mice and humans and the apparent variability of the EPR effect in human cancer. PLD is a complex product and we are still in a learning curve regarding a number of factors such as its interaction with the complement system and its immune modulatory properties, as well as its integration in multimodality therapy that may potentiate its value and role in cancer therapy.

Pegylated liposomal doxorubicin combined with cyclophosphamide and vincristine in pediatric patients with relapsed/refractory solid tumor: a single-arm, open-label, phase I study

Background

The combined vincristine, pegylated liposomal doxorubicin (PLD), and cyclophosphamide (VPC) regimen has never been studied in pediatric patients.

Methods

This open-label, single-center, single-arm phase I study utilizing a "3 + 3" design enrolled children with relapsed/refractory (R/R) solid tumors. Three dose levels of PLD (Duomeisu®) were studied (30, 40, or 50 mg/m2) in combination with cyclophosphamide (1500 mg/m2), mesna (1500 mg/m2), and vincristine (1.5 mg/m2, maximum 2 mg) once every 3 weeks. The primary endpoints included safety, the maximum tolerated dose (MTD) of PLD (Duomeisu®), and the recommended phase 2 dose (RP2D) of PLD (Duomeisu®) for further phase 2 investigation. The secondary endpoints were objective response rate (ORR) and disease control rate (DCR). This study is registered with ClinicalTrials.gov, NCT04213612.

Findings

Between January 7, 2020, and November 18, 2021, 34 patients were eligible and evaluable for toxicity, while 26 patients were evaluable for response. The MTD of PLD (Duomeisu®) was 30 mg/m2. The most common adverse event (AE) was grade 3 or 4 neutropenia (61.8%). The most common grade 1 or 2 non-hematologic AE and cardiotoxicity effects were vomiting (35.3%) and abnormal electrocardiogram T waves (20.6%), respectively. ORR and DCR to VPC regimen after two cycles were 50.0% and 92.3%, respectively. Targeted gene panel sequencing revealed the activation of TP53 mutation may be an adverse prognostic factor.

Interpretation

The VPC regimen showed a promising safety profile and had preliminary efficacy in children with R/R solid tumors. The RP2D for PLD (Duomeisu®) combined with cyclophosphamide and vincristine is 30 mg/m2 once every 3 weeks.

Funding

CSPC Ouyi Pharmaceutical Co., Ltd., Shijiazhuang, the National Key Research and Development Program of China [No. 2022YFC2705005], the National Natural Science Foundation of China [No. 82203303], and the Basic and Applied Basic Research Foundation of Guangdong Province [No. 2021A1515110234].

Nanoparticles-encapsulated doxorubicin alleviates drug resistance of osteosarcoma via inducing ferroptosis

To determine the effects of polymeric nanoparticle for doxorubicin (Dox) delivery and treatment of drug-resistant Osteosarcoma (OS) cells. Methoxy-polyethylene glycol amino (mPEG-NH2) and platinum bio-mimetic polycaprolactone-cysteine (PtBMLC) were crosslinked to obtain glutathione (GSH)-responsive mPEG-NH2-PtBMLC polymer to encapsulate Dox (named as Nano-Dox). The particle size and zeta potential of the nanoparticles were measured, and internalization of Dox by OS cells was observed. After treatment with Nano-Dox, cell proliferation was determined by cell counting kit 8 (CCK-8) and colony formation assay. Cell migration and invasion were determined by Transwell assay. Cell cycle arrest was assessed by flow cytometry. The induction of ferroptosis was analyzed by abnormal accumulation of total iron, Fe2+. Nano-Dox exhibited a stronger localization in OS cells (p < 0.01). Nano-Dox induced more significant suppression of drug-resistant OS cell growth (p < 0.01), migration (p < 0.01), and invasion (p < 0.01), compared with the single Dox treatment group, along with decreased expression of N-cadherin, Snail, and Vimentin, suggesting impaired cancer migration and invasion. The treatment with Nano-Dox induced notable cell cycle arrest at G0/G1 phase (p < 0.01) and accumulation of iron, Fe2+, and MDA (p < 0.01), as well as suppressed the protein levels of glutathione peroxidase 4 (GPX4) and SLC7A11. Administration of ferroptosis inhibitor (Fer-1) reversed the anti-proliferation effects of Nano-Dox (p < 0.01). The Dox delivered by the polymeric nanoparticle system notably enhanced its effects on suppressing the growth, migration, and invasion of drug-resistant OS cells via inducing ferroptosis. The application of environment response polymer enhanced the delivery of Dox and the therapeutic effects on OS.

The Survival Benefit of Pegylated Liposomal Doxorubicin-Based Neoadjuvant Chemotherapy in the Management of Breast Cancer

Purpose: This study aims to evaluate the short-term outcomes and prognosis and the cardiac safety of pegylated liposomal doxorubicin (PLD)-based neoadjuvant chemotherapy (NAC) compared with epirubicin-based therapy in breast cancer treatment. Methods: In total, 304 patients diagnosed with stages II and III breast cancer were enrolled that included 97 cases treated with PLD and 207 controls treated with epirubicin in NAC. The effectiveness of the antibreast cancer treatment was evaluated using overall survival (OS) and disease-free survival (DFS) metrics, whereas cardiac toxicity was measured through the left ventricular ejection fraction (LVEF) and electrocardiogram (ECG) assessments. Results: The 5-year DFS and OS rates in the PLD group were 84.5% and 88.7% (with 15 recurrences and 11 deaths), respectively, whereas in the control group, these rates were 72.9% and 79.2% (with 56 recurrences and 43 deaths). Regarding cardiac toxicity, there was no significant difference in ECG abnormalities or LVEF decline between the two groups. Conclusions: The study suggests that PLD-based NAC may provide substantial benefits in terms of DFS and OS, along with a safe cardiac toxicity profile, in patients with stage II-III breast cancer.

Nanoparticles as Drug Delivery Systems: A Review of the Implication of Nanoparticles' Physicochemical Properties on Responses in Biological Systems

In the last four decades, nanotechnology has gained momentum with no sign of slowing down. The application of inventions or products from nanotechnology has revolutionised all aspects of everyday life ranging from medical applications to its impact on the food industry. Nanoparticles have made it possible to significantly extend the shelf lives of food product, improve intracellular delivery of hydrophobic drugs and improve the efficacy of specific therapeutics such as anticancer agents. As a consequence, nanotechnology has not only impacted the global standard of living but has also impacted the global economy. In this review, the characteristics of nanoparticles that confers them with suitable and potentially toxic biological effects, as well as their applications in different biological fields and nanoparticle-based drugs and delivery systems in biomedicine including nano-based drugs currently approved by the U.S. Food and Drug Administration (FDA) are discussed. The possible consequence of continuous exposure to nanoparticles due to the increased use of nanotechnology and possible solution is also highlighted.

Pegylated liposomal doxorubicin (Duomeisu®) monotherapy in patients with HER2-negative metastatic breast cancer heavily pretreated with anthracycline and taxanes: a single-arm, phase II study

PURPOSE

To evaluate the efficacy and safety of pegylated liposomal doxorubicin (PLD) in patients with human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer (MBC) heavily pretreated with anthracycline and taxanes.

METHODS

In this single-arm, phase II study, patients with HER2-negative MBC previously treated with anthracycline and taxanes as second- to fifth chemotherapy received PLD (Duomeisu^®, generic doxorubicin hydrochloride liposome) 40 mg/m² every 4 weeks until disease progression, unacceptable toxicity, or completion of six cycles. Primary endpoint was progression-free survival (PFS). Secondary endpoints included overall survival (OS), objective response rate (ORR), disease control rate (DCR), clinical benefit rate (CBR), and safety.

RESULTS

Of 44 enrolled patients (median age, 53.5 years; range, 34-69), 41 and 36 were evaluable for safety and efficacy, respectively. In total, 59.1% (26/44) of patients had ≥ 3 metastatic sites, 86.4% (38/44) had visceral disease, and 63.6% (28/44) had liver metastases. Median PFS was 3.7 months (95% confidence interval [CI] 3.3-4.1) and median OS was 15.0 months (95% CI 12.1-17.9). ORR, DCR, and CBR were 16.7%, 63.9%, and 36.1%, respectively. The most common adverse events (AEs) were leukopenia (53.7%), fatigue (46.3%), and neutropenia (41.5%), with no grade 4/5 AEs. The most common grade 3 AEs were neutropenia (7.3%) and fatigue (4.9%). Patients experienced palmar-plantar-erythrodysesthesia (24.4%, 2.4% grade 3), stomatitis (19.5%, 7.3% grade 2), and alopecia (7.3%). One patient displayed a left ventricular ejection fraction decline of 11.4% from baseline after five cycles of PLD therapy.

CONCLUSION

PLD (Duomeisu^®) 40 mg/m² every 4 weeks was effective and well-tolerated in patients with HER2-negative MBC heavily pretreated with anthracycline and taxanes, revealing a potentially viable treatment option for this population. Trial registration Chinese Clinical Trial Registry: ChiCTR1900022568.

New advances in pharmaceutical strategies for sensitizing anti-PD-1 immunotherapy and clinical research

Attempts have been made continuously to use nano-drug delivery system (NDDS) to improve the effect of antitumor therapy. In recent years, especially in the application of immunotherapy represented by antiprogrammed death receptor 1 (anti-PD-1), it has been vigorously developed. Nanodelivery systems are significantly superior in a number of aspects including increasing the solubility of insoluble drugs, enhancing their targeting ability, prolonging their half-life, and reducing side effects. It can not only directly improve the efficacy of anti-PD-1 immunotherapy, but also indirectly enhance the antineoplastic efficacy of immunotherapy by boosting the effectiveness of therapeutic modalities such as chemotherapy, radiotherapy, photothermal, and photodynamic therapy (PTT/PDT). Here, we summarize the studies published in recent years on the use of nanotechnology in pharmaceutics to improve the efficacy of anti-PD-1 antibodies, analyze their characteristics and shortcomings, and combine with the current clinical research on anti-PD-1 antibodies to provide a reference for the design of future nanocarriers, so as to further expand the clinical application prospects of NDDSs. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Ultrasound-Responsive Nanocarriers for Breast Cancer Chemotherapy

Breast cancer is the most common type of cancer and it is treated with surgical intervention, radiotherapy, chemotherapy, or a combination of these regimens. Despite chemotherapy's ample use, it has limitations such as bioavailability, adverse side effects, high-dose requirements, low therapeutic indices, multiple drug resistance development, and non-specific targeting. Drug delivery vehicles or carriers, of which nanocarriers are prominent, have been introduced to overcome chemotherapy limitations. Nanocarriers have been preferentially used in breast cancer chemotherapy because of their role in protecting therapeutic agents from degradation, enabling efficient drug concentration in target cells or tissues, overcoming drug resistance, and their relatively small size. However, nanocarriers are affected by physiological barriers, bioavailability of transported drugs, and other factors. To resolve these issues, the use of external stimuli has been introduced, such as ultrasound, infrared light, thermal stimulation, microwaves, and X-rays. Recently, ultrasound-responsive nanocarriers have become popular because they are cost-effective, non-invasive, specific, tissue-penetrating, and deliver high drug concentrations to their target. In this paper, we review recent developments in ultrasound-guided nanocarriers for breast cancer chemotherapy, discuss the relevant challenges, and provide insights into future directions.

Nanomedicine-Based Delivery Strategies for Breast Cancer Treatment and Management

Breast cancer is one of the most common types of cancer among women globally. It is caused by mutations in the estrogen/progesterone receptors and conventional treatment methods are commonly utilized. About 70–80 percent of individuals with the early-stage non-metastatic disease may be cured. Conventional treatment is far less than the optimal ratio, as demonstrated through the high mortality rate of women with this cancer. However, conventional treatment methods like surgery, radiotherapy, and chemotherapy are not as effective as expected and lead to concerns about low bioavailability, low cellular uptake, emerging resistance, and adverse toxicities. A nanomedicine-based approach is a promising alternative for breast cancer treatment. The present era is witnessing rapid advancements in nanomedicine as a platform for investigating novel therapeutic applications and modern intelligent healthcare management strategies. This paper focuses on nanomedicine-based therapeutic interventions that are becoming more widely accepted for improving treatment effectiveness and reducing undesired side effects in breast cancer patients. By evaluating the state-of-the-art tools and taking the challenges involved into consideration, various aspects of the proposed nano-enabled therapeutic approaches have been discussed in this review.

Current Trends and Challenges in Pharmacoeconomic Aspects of Nanocarriers as Drug Delivery Systems for Cancer Treatment

Nanotherapy is a part of nanomedicine that involves nanoparticles as carriers to deliver drugs to target locations. This novel targeting approach has been found to resolve various problems, especially those associated with cancer treatment. In nanotherapy, the carrier plays a crucial role in handling many of the existing challenges, including drug protection before early-stage degradations of active substances, allowing them to reach targeted cells and overcome cell resistance mechanisms. The present review comprises the following sections: the first part presents the introduction of pharmacoeconomics as a branch of healthcare economics, the second part covers various beneficial aspects of the use of nanocarriers for in vitro, in vivo, and pre- and clinical studies, as well as discussion on drug resistance problem and present solutions to overcome it. In the third part, progress in drug manufacturing and optimization of the process of nanoparticle synthesis were discussed. Finally, pharmacokinetic and toxicological properties of nanoformulations due to up-to-date studies were summarized. In this review, the most recent developments in the field of nanotechnology's economic impact, particularly beneficial applications in medicine were presented. Primarily focus on cancer treatment, but also discussion on other fields of application, which are strongly associated with cancer epidemiology and treatment, was made. In addition, the current limitations of nanomedicine and its huge potential to improve and develop the health care system were presented.

Delivery of doxorubicin loaded P18 conjugated-poly(2-ethyl-oxazoline)-DOPE nanoliposomes for targeted therapy of breast cancer

Breast cancer, a heterogeneous disease, has the highest incidence rate and is a major cause of death in females worldwide. Drug delivery by using nanotechnology has shown great promise for improving cancer treatment. Nanoliposomes are known to have enhanced accumulation ability in tumors due to prolonged systemic circulation. Peptide 18 (P18), a tumor homing peptide targeting keratin-1 (KRT-1), was previously shown to have high binding affinity towards breast cancer cells. In this study, we investigate the ability of P18 conjugated PEtOx-DOPE nanoliposomes (P18-PEtOx-DOPE) for the targeted delivery of doxorubicin to AU565 breast cancer model. Toxicology studies of PEtOx-DOPE nanoliposomes performed on normal breast epithelial cells (MCF10A), showed minimal toxicity. Doxorubicin delivery by P18-PEtOx-DOPE to AU565 cells induces cytotoxicity in a dose and time dependent manner causing mitotic arrest in G2/M phase at 24 h. Anti-cancer activity of P18-PEtOx-DOPE-DOX nanoliposomes on AU565 cells was detected by Annexin V/PI apoptosis assay. In terms of in vivo antitumor efficacy, P18-PEtOx-DOPE-DOX nanoliposomes administration to AU565 CD-1 nu/nu mice model showed significant decrease in tumor volume suggesting that DOX delivered by these nanoliposomes elicited a strong antitumor response comparable to the free delivery of doxorubicin. Overall, our results offered preclinical proof for the use of P18-PEtOx-DOPE-DOX nanoliposomes in KRT-1⁺ breast cancer therapy.

Advances in the application of nanotechnology in reducing cardiotoxicity induced by cancer chemotherapy

Advances in the development of anti-tumour drugs and related technologies have resulted in a significant increase in the number of cancer survivors. However, the incidence of chemotherapy-induced cardiotoxicity (CIC) has been rising continuously, threatening their long-term survival. The integration of nanotechnology and biomedicine has brought about an unprecedented technological revolution and has promoted the progress of anti-tumour therapy. In this review, we summarised the possible mechanisms of CIC, evaluated the role of nanoparticles (including liposomes, polymeric micelles, dendrimers, and hydrogels) as drug carriers in preventing cardiotoxicity and proposed five advantages of nanotechnology in reducing cardiotoxicity: Liposomes cannot easily penetrate the heart's endothelial barrier; optimized delivery strategies reduce distribution in important organs, such as the heart; targeting the tumour microenvironment and niche; stimulus-responsive polymer nano-drug carriers rapidly iterate; better economic benefits were obtained. Nanoparticles can effectively deliver chemotherapeutic drugs to tumour tissues, while reducing the toxicity to heart tissues, and break through the dilemma of existing chemotherapy to a certain extent. It is important to explore the interactions between the physicochemical properties of nanoparticles and optimize the highly specific tumour targeting strategy in the future.

Liposomes: An Emerging Approach for the Treatment of Cancer

BACKGROUND

Conventional drug delivery agents for a life-threatening disease, i.e., cancer, lack specificity towards cancer cells, producing a greater degree of side effects in the normal cells with a poor therapeutic index. These toxic side effects often limit dose escalation of anti-cancer drugs, leading to incomplete tumor suppression/ cancer eradication, early disease relapse, and ultimately, the development of drug resistance. Accordingly, targeting the tumor vasculatures is essential for the treatment of cancer.

OBJECTIVE

To search and describe a safer drug delivery carrier for the treatment of cancer with reduced systemic toxicities.

METHOD

Data were collected from Medline, PubMed, Google Scholar, Science Direct using the following keywords: 'liposomes', 'nanocarriers', 'targeted drug delivery', 'ligands', 'liposome for anti-cancerous drugs', 'treatment for cancer' and 'receptor targeting.'

RESULTS

Liposomes have provided a safe platform for the targeted delivery of encapsulated anti-cancer drugs for the treatment of cancer, which results in the reduction of the cytotoxic side effects of anti-cancer drugs on normal cells.

CONCLUSION

Liposomal targeting is a better emerging approach as an advanced drug delivery carrier with targeting ligands for anti-cancer agents.

Fever and breast cancer: A critical review of the literature and possible underlying mechanisms

Fever is a common feature in various pathological conditions that manifests a series of molecular events in the internal milieu. Much less attention has been paid to the clinical importance and the management of fever in breast cancer patients. However, several studies have reported an association between postoperative fever and poor treatment outcomes in breast cancer patients. The fever is a side effect of chemotherapy and a manifestation of cancer recurrence. The postmenopausal breast cancer patients experience another body temperature disturbance that is known as a hot flashes. Here, we reviewed the literature regarding postoperative fever and the possible underlying molecular and cellular mechanisms. Then the efficacy of non-steroidal anti-inflammatory drugs was discussed as a therapeutic option to control postoperative fever. Finally, we reviewed the chemotherapy-induced neutropenic fever and cancer vaccination-induced fever.

Long-Term Cardiac Safety and Survival Outcomes of Neoadjuvant Pegylated Liposomal Doxorubicin in Elderly Patients or Prone to Cardiotoxicity and Triple Negative Breast Cancer. Final Results of the Multicentre Phase II CAPRICE Study

Background

The CAPRICE trial was designed to specifically evaluate neoadjuvant pegylated liposomal doxorubicin (PLD) in elderly patients or in those with other cardiovascular risk factors in whom conventional doxorubicin was contraindicated. The primary analysis of the study showed a pathological complete response (pCR) of 32% and no significant decreases in LVEF during chemotherapy. Here, we report important secondary study objectives: 5-year cardiac safety, disease-free survival (DFS), overall survival (OS) and breast cancer specific survival (BCSS).

Methods

In this multicentre, single-arm, phase II trial, elderly patients or those prone to cardiotoxicity and high risk stage II-IIIB breast cancer received PLD (35 mg/m²) plus cyclophosphamide (600 mg/m²) every 4 weeks for 4 cycles, followed by paclitaxel for 12 weeks as neoadjuvant chemotherapy (NAC). Left ventricular ejection fraction (LVEF) monitorization, electrocardiograms and cardiac questionnaires were performed at baseline, during treatment and at 9, 16, 28 and 40 weeks thereafter. The primary endpoint was pCR and 5-year cardiac safety, DFS, BCSS and OS were also analyzed.

Results

Between Oct 2007, and Jun 2010, 50 eligible patients were included. Median age was 73 (35-84) years, 84% were older than 65; 64% of patients suffered from hypertension, and 10% had prior cardiac disease. Most of tumors (88%) were triple negative. No significant decreases in LVEF were observed. The mean baseline LVEF was 66.6% (52-86) and after a median follow-up of 5 years, mean LVEF was 66 (54.5-73). For intention to treat population, 5-year DFS was 50% (95% CI 40.2-68.1) and 5-year OS was 56% (95%CI 41.2-68.4). There were 8 non-cancer related deaths, achieving a 5 years BCSS of 67.74% (CI 95%:54.31%- 81.18%).

Conclusion

At 5-year follow-up, this PLD-based NAC regimen continued to be cardiac-safe and effective in a population of very high-risk breast cancer patients. This scheme should be considered as an option in elderly patients or in those with other risks of developing cardiotoxicity.

Trial Registration Number

ClinicalTrials.gov reference NCT00563953.

Metronomic vinorelbine is an excellent and safe treatment for advanced breast cancer: a retrospective, observational study

Advanced breast cancer (ABC) has become a chronic disease. In such a situation, an effective therapy with low toxicities and economically acceptable is needed. Metronomic vinorelbine (mVNR) has been proved to be effective on the control of MBC. The aim of this study is to evaluate the efficacy and safety of mVNR as the salvage therapy for patients with ABC. Oral vinorelbine (VNR) was administered at 70 mg/m2, fractionated on days 1, 3, and 5, for 3 weeks on and 1 week off. Once the mVNR was combined with trastuzumab, or was combined with bevacizumab, the schedule was changed to 2 weeks on and 1 week off. Clinical data of patients with ABC who had received treatment with mVNR and tumor characteristics were collected and analyzed. From Mar. 2013 to Dec, 2020, there were 90 patients with ABC received mVNR. The overall response rate was 53.3% and overall disease control rate (DCR) was 78.9% in this study, including 4 (4.4%) cases reached complete response, 44 (48.9%) cases reached partial response and 23 (25.6%) cases were table disease. The median time to treatment failure (TTF) of the Lumina A patients was 13.3 months, Lumina B patients was 9.1 months, Her-2 enrich patients was 8.9 months, and triple negative breast cancer (TNBC) patients was 5.6 months. Median overall survival time for Lumina A, Lumina B, Her-2 enrich and TNBC were 54.6 months, 53.3 months, 59.5 months and 24.5 months separately. Side effects were minimal and manageable. Metronomic VNR can be an effective treatment for ABC either works as a switch maintenance or salvage therapy. In combination with target therapy or hormonal therapy, mVNR can further improve TTF and DCR with minimal toxicities. Further study should focus on the optimal dosage, schedule and combination regimen.

From Nanoparticles to Cancer Nanomedicine: Old Problems with New Solutions

Anticancer nanomedicines have been studied over 30 years, but fewer than 10 formulations have been approved for clinical therapy today. Despite abundant options of anticancer drugs, it remains challenging to have agents specifically target cancer cells while reducing collateral toxicity to healthy tissue. Nanocompartments that can be selective toward points deeply within malignant tissues are a promising concept, but the heterogeneity of tumor tissue, inefficiency of cargo loading and releasing, and low uniformity of manufacture required from preclinical to commercialization are major obstacles. Technological advances have been made in this field, creating engineered nanomaterials with improved uniformity, flexibility of cargo loading, diversity of surface modification, and less inducible immune responses. This review highlights the developmental process of approved nanomedicines and the opportunities for novel materials that combine insights of tumors and nanotechnology to develop a more effective nanomedicine for cancer patients.

Optimized 5-Fluorouridine Prodrug for Co-Loading with Doxorubicin in Clinically Relevant Liposomes

Liposome-based drug delivery systems have allowed for better drug tolerability and longer circulation times but are often optimized for a single agent due to the inherent difficulty of co-encapsulating two drugs with differing chemical profiles. Here, we design and test a prodrug based on a ribosylated nucleoside form of 5-fluorouracil, 5-fluorouridine (5FUR), with the final purpose of co-encapsulation with doxorubicin (DOX) in liposomes. To improve the loading of 5FUR, we developed two 5FUR prodrugs that involved the conjugation of either one or three moieties of tryptophan (W) known respectively as, 5FUR−W and 5FUR−W₃. 5FUR−W demonstrated greater chemical stability than 5FUR−W3 and allowed for improved loading with fewer possible byproducts from tryptophan hydrolysis. Varied drug ratios of 5FUR−W: DOX were encapsulated for in vivo testing in the highly aggressive 4T1 murine breast cancer model. A liposomal molar ratio of 2.5 5FUR−W: DOX achieved a 62.6% reduction in tumor size compared to the untreated control group and a 33% reduction compared to clinical doxorubicin liposomes in a proof-of-concept study to demonstrate the viability of the co-encapsulated liposomes. We believe that the new prodrug 5FUR−W demonstrates a prodrug design with clinical translatability by reducing the number of byproducts produced by the hydrolysis of tryptophan, while also allowing for loading flexibility.

Comparison of transcatheter arterial chemoembolization with raltitrexed plus liposomal doxorubicin vs. tegafur plus pirarubicin for unresectable hepatocellular carcinoma

BACKGROUND

There is still no general consensus on the optimal chemotherapeutic agent selection for transcatheter arterial chemoembolization (TACE) in unresectable hepatocellular carcinoma (HCC). The present study aimed to compare the efficacy and safety of TACE with raltitrexed plus liposomal doxorubicin (R + PGLD) vs. tegafur plus pirarubicin (T + P) in patients with unresectable HCC.

METHODS

A total of 148 patients with unresectable HCC treated with TACE between January 2012 and December 2016 were retrospectively analyzed. Of them, 74 patients were in the R + PGLD group and 74 patients were in the T + P group (1:1). The treatment response of the tumor, overall survival (OS) time, and adverse effects were compared between the two groups.

RESULTS

There were no significant differences in patient characteristics or embolization effect (lipiodol deposition) between the two groups (P>0.05). R + PGLD treatment had a better clinical efficacy than T + P treatment (OR: 64.9% vs. 45.9%, P=0.031; DC: 89.2% vs. 74.3%, P=0.032). Portal vein invasion, hepatic vein invasion, tumor size and BCLC stage were associated with OR or DC after TACE using R + PGLD treatment. Survival analysis revealed that patients who received TACE with R + PGLD had a better prognosis than those treated with T + P. Moreover, some complications in the R + PGLD group, including vomiting, myelosuppression and cardiotoxicity, were significantly lower than those in the T + P group (P<0.05).

CONCLUSIONS

TACE with raltitrexed and liposomal doxorubicin could reduce the incidence of adverse reactions and significantly improve the OS of patients with unresectable HCC.

ICON: a randomized phase IIb study evaluating immunogenic chemotherapy combined with ipilimumab and nivolumab in patients with metastatic hormone receptor positive breast cancer

BACKGROUND

Immunotherapy with checkpoint inhibitors (CPI) targeting PD-1 or CTLA-4 has emerged as an important treatment modality for several cancer forms. In hormone receptor positive breast cancer (HR + BC), this therapeutic approach is largely unexplored. We have started a clinical trial, ICON (CA209-9FN), evaluating CPI combined with selected chemotherapy in patients with metastatic HR + BC. The tumor lymphocyte infiltration is predictive for the effect of chemotherapy in BC. In ICON, we use anthracycline, which are considered as "immunogenic" chemotherapy, and low-dose cyclophosphamide, which has been reported to counter immunosuppressive cells.

METHODS

ICON is a randomized exploratory phase IIb study evaluating the safety and efficacy of combining nivolumab (nivo; anti-PD-1) and ipilimumab (ipi; anti-CTLA-4) with chemotherapy in subjects with metastatic HR + BC. Primary objectives are aassessment of toxicity and progression-free survival. The trial will enrol 75 evaluable subjects, randomized 2:3 into two arms (A:B). Patients in Arm A receive only chemotherapy, i.e. pegylated liposomal doxorubicin (PLD 20 mg/m² intravenously every 2nd week) + cyclophosphamide (cyclo; 50 mg per day, first 2 weeks in each 4 week cycle). Patients in Arm B receive PLD + cyclo + ipilimumab (1 mg intravenously every 6th week) + nivolumab (240 mg intravenously every 2nd week). Patients in arm A will be offered ipi + nivo after disease progression.

DISCUSSION

ICON is among the first clinical trials combining chemotherapy with PD-1 and CTLA-4 blockade, and the first in BC. There is a strong preclinical rationale for exploring if anthracyclines, which are considered to induce immunogenic cell death, synergize with CPI, and for combining PD-1 and CTLA-4 blockade, as these checkpoints are important in different phases of the immune response. If the ICON trial suggests acceptable safety and provide a signal of clinical efficacy, further studies are warranted. The cross-over patients from Arm A receiving ipilimumab/nivolumab without concomitant chemotherapy represent the first BC cohort receiving this therapy. The ICON trial includes a series of translational sub-projects addressing clinically important knowledge gaps. These studies may uncover biomarkers or mechanisms of efficacy and resistance, thereby informing the development of novel combinatory regimes and of personalised biomarker-based therapy. Trial registration NCT03409198, Jan 24th 2018; https://clinicaltrials.gov/ct2/show/record/NCT03409198.

ALICE: a randomized placebo-controlled phase II study evaluating atezolizumab combined with immunogenic chemotherapy in patients with metastatic triple-negative breast cancer

BACKGROUND

Immunotherapy with checkpoint inhibitors (CI) represents an important novel development in cancer treatment. Metastatic triple-negative breast cancer (mTNBC) is incurable, with a median survival of only ~ 13 months. We have initiated the randomized placebo-controlled phase IIb study ALICE, evaluating PD-L1 blockade combined with immunogenic chemotherapy in mTNBC patients (n = 75). Intriguingly, the host immune response is strongly predictive for the effect of chemotherapy in mTNBC. In the ALICE trial, we release the brake on the immune response by use of atezolizumab, an inhibitory antibody against PD-L1. We utilize anthracyclines, shown to trigger the immune system, and low-dose cyclophosphamide, which has been reported to counter immunosuppressive cells.

METHODS

ALICE is a randomized, double-blind, placebo-controlled exploratory phase II study evaluating the safety and efficacy of atezolizumab when combined with immunogenic chemotherapy in subjects with mTNBC. The trial will enroll 75 evaluable subjects, randomized 2:3 into two arms (A:B). The patients receive identical chemotherapy, i.e. pegylated liposomal doxorubicin (PLD 20 mg/m² intravenously every 2nd week) + cyclophosphamide (50 mg per day, first 2 weeks in each 4 week cycle). Patients in arm A receive placebo, while patients in arm B receive atezolizumab. The primary objectives are assessment of toxicity and progression-free survival. The secondary objectives include overall survival, tumor response rate, clinical benefit rate, patient reported outcomes, biomarkers and assessment of tumor-immune evolution during therapy.

DISCUSSION

The question of how CI should be combined with chemotherapy, is a key challenge facing the field. There is a strong preclinical rationale for exploring if anthracyclines, which are considered to induce immunogenic cell death, synergize with PD-L1 blockade, and if low-dose cyclophosphamide counters tumor tolerance. However, the data from patients is as yet very limited, and the clinical evaluation of these hypotheses is among the key objectives in the ALICE trial. The study includes extensive biobanking and translational sub-projects, also addressing other clinically important questions. These analyses may uncover mechanisms of drug efficacy or tumor resistance, and identify biomarkers allowing personalized therapy. If the trial suggests acceptable safety of the ALICE therapy and provide a signal of clinical efficacy, further studies are warranted. Trial registration NCT03164993, May 24th 2017; https://clinicaltrials.gov/ct2/show/record/NCT03164993.

Pegylated liposomal doxorubicin as neoadjuvant therapy for stage II-III locally advanced breast cancer

Conventional anthracyclines represent a cornerstone drug in the treatment of breast cancer. Pegylated liposomal doxorubicin (PLD) has similar efficacy to anthracyclines with reduced toxicity. This study was to compare the efficacy and safety of PLD-based neoadjuvant chemotherapy (NAC) with epirubicin-based treatment for breast cancer. 81 breast cancer patients were enrolled in this retrospective study. The objective response rate (ORR) in the PLD group was 74.1%, the 3-year disease-free survival(DFS) and overall survival(OS) were 81.5% and 88.9%. The PLD group achieved similar efficacy to the EPI group. The PLD group showed a low rate of neutropenia , nausea and vomiting, but a higher rate of mucositis and hand-foot syndrome. In neoadjuvant chemotherapy for invasive breast cancer, PLD provides comparable efficacy to epirubicin with a safe cardiac toxicity profile and manageable adverse effects.

Progress in Polymeric Nano-Medicines for Theranostic Cancer Treatment

Cancer is a life-threatening disease killing millions of people globally. Among various medical treatments, nano-medicines are gaining importance continuously. Many nanocarriers have been developed for treatment, but polymerically-based ones are acquiring importance due to their targeting capabilities, biodegradability, biocompatibility, capacity for drug loading and long blood circulation time. The present article describes progress in polymeric nano-medicines for theranostic cancer treatment, which includes cancer diagnosis and treatment in a single dosage form. The article covers the applications of natural and synthetic polymers in cancer diagnosis and treatment. Efforts were also made to discuss the merits and demerits of such polymers; the status of approved nano-medicines; and future perspectives.

Pegylated liposomal doxorubicin plus cyclophosphamide followed by docetaxel as neoadjuvant chemotherapy in locally advanced breast cancer (registration number: ChiCTR1900023052)

Anthracyclines have a profound effect on breast cancer. However, at higher dosages, there are many toxic side effects associated with their use; these include bone marrow suppression, alopecia, gastrointestinal reactions and cardiotoxicity. Pegylated liposomal doxorubicin (PEG-LG) has been demonstrated to achieve equivalent efficacy to conventional doxorubicin, with significantly lower cardiotoxicity. We conducted an open-label, multicenter, single-armed clinical trial useing an NAC regimen based on four cycles of PEG-LD 40 mg/m² plus cyclophosphamide (CPM) 600 mg/m² on day 1 of a 21 day schedule, followed by four cycles of docetaxel (DTX) 85 mg/m² on day 1 of a 21 day schedule. The primary endpoint analysed was the pathological complete response rate (pCR) in the breast, while treatment toxicities and safety were also assessed. The results showed that the breast pCR rate was 18.75% (95% CI 11.5-26.0%). Among the different molecular cancer types, the triple negative breast cancer patients had the highest pCR, at 43.75%. No significant decrease in left ventricular ejection fraction was observed. Our data tends to draw the conclusion that this regimen is a viable option for the neoadjuvant treatment of patients with LABC, especially in the triple-negative subtype and patients with heart abnormalities. We believe the efficacy and the safety of this regimen is likely to be the same based on published data from other studies but that this cannot be certain without a randomized trial.

Inhibition of circular RNA CDR1as increases chemosensitivity of 5-FU-resistant BC cells through up-regulating miR-7

This study aims to explore the mechanism of Circular RNA CDR1as implicating in regulating 5-fluorouracil (5-FU) chemosensitivity in breast cancer (BC) by competitively inhibiting miR-7 to regulate CCNE1. Expressions of CDR1as and miR-7 in 5-FU-resistant BC cells were determined by RT-PCR. CCK-8, colony formation assay and flow cytometry were applied to measure half maximal inhibitory concentration (IC50), 5-Fu chemosensitivity and cell apoptosis. Western blot was used to detect the expressions of apoptosis-related factors. CDR1as was elevated while miR-7 was inhibited in 5-FU-resistant BC cells. Cells transfected with si-CDR1as or miR-7 mimic had decreased IC50 and colony formation rate, increased expressions of Bax/Bcl2 and cleaved-Caspase-3/Caspase-3, indicating inhibition of CDR1as and overexpression of miR-7 enhances the chemosensitity of 5-FU-resistant BC cells. Targetscan software indicates a binding site of CDR1as and miR-7 and that CCNE1 is a target gene of miR-7. miR-7 can gather CDR1as in BC cells and can inhibit CCNE1. In comparison to si-CDR1as group, CCNE1 was increased and chemosensitivity to 5-Fu was suppressed in si-CDR1as + miR-7 inhibitor group. When compared with miR-7 mimic group, CDR1as + miR-7 mimic group had increased CCNE1 and decreased chemosensitivity to 5-Fu. Nude mouse model of BC demonstrated that the growth of xenotransplanted tumour in si-CDR1as + miR-7 inhibitor group was faster than that in si-CDR1as group. The tumour growth in CDR1as + miR-7 mimic group was faster than that in miR-7 mimic group. CDR1as may regulate chemosensitivity of 5-FU-resistant BC cells by inhibiting miR-7 to regulate CCNE1.

Anticancer and cardio-protective effects of liposomal doxorubicin in the treatment of breast cancer

Breast cancer (BC) is a highly prevalent disease, accounting for the second highest number of cancer-related mortalities worldwide. The anthracycline doxorubicin (DOX), isolated from Streptomyces peucetius var. caesius, is a potent chemotherapeutic drug that is successfully used to treat various forms of liquid and solid tumors and is currently approved to treat BC. DOX exerts its effects by intercalation into DNA and inhibition of topoisomerases I and II, causing damage to DNA and the formation of reactive oxygen species (ROS), resulting in the activation of caspases, which ultimately leads to apoptosis. Unfortunately, DOX also can cause cardiotoxicity, with patients only allowed a cumulative lifetime dose of 550 mg/m². Efforts to decrease cardiotoxicity and to increase the blood circulation time of DOX led to the US Food and Drug Administration (FDA) approval of a PEGylated liposomal formulation (L-DOX), Doxil^® (known internationally as Caelyx^®). Both exhibit better cardiovascular safety profiles; however, they are not currently FDA approved for the treatment of metastatic BC. Here, we provide detailed insights into the mechanism of action of L-DOX and its most common side effects and highlight results of its use in clinical trials for the treatment of BC as single agent and in combination with other commonly used chemotherapeutics.

Sertoli Cells Loaded with Doxorubicin in Lipid Micelles Reduced Tumor Burden and Dox-Induced Toxicity

The toxic side effects of doxorubicin (Dox) limit its long-term use as a lung cancer chemotherapeutic. Additionally, drug delivery to the deep lung is challenging. To address these challenges, isolated rat Sertoli cells (SCs) were preloaded with Dox conjugated to lipid micelle nanoparticles (SC-DLMNs) and delivered to mouse lungs. These immunocompetent cells, when injected intravenously, travel to the lung, deliver the payload, and get cleared by the system quickly without causing any adverse reaction. We observed that SC-DLMNs effectively treated Lewis lung carcinoma 1-induced lung tumors in mice and the drug efficacy was comparable to SC-Dox treatment. Mice treated with SC-DLMNs also showed significantly less toxicity compared to those treated with SC-Dox. The encapsulation of Dox in lipid micelle nanoparticles reduced the toxicity of Dox and the SC-based delivery method ensured drug delivery to the deep lung without evoking any immune response. Taken together, these results provide a novel SC-based nanoparticle drug delivery method for improved therapeutic outcome of cardiotoxic antilung cancer drugs.

Proanthocyanidins from Uncaria rhynchophylla induced apoptosis in MDA-MB-231 breast cancer cells while enhancing cytotoxic effects of 5-fluorouracil

Breast cancer is the most frequently diagnosed cancer and cause of cancer death in women worldwide. Current treatments often result in systematic toxicity and drug resistance. Combinational use of non-toxic phytochemicals with chemotherapeutic agents to enhance the efficacy and reduce toxicity would be one promising approach. In this study, bioactive proanthocyanidins from Uncaria rhynchophylla (UPAs) were isolated and their anti-breast cancer effects alone and in combination with 5- fluorouracil (5-FU) were investigated in MDA-MB-231 breast cancer cells. The results showed that UPAs significantly inhibited cell viability and migration ability in a dose-dependent manner. Moreover, UPAs induced apoptosis in a dose-dependent manner which was associated with increased cellular reactive oxygen species production, loss of mitochondrial membrane potential, increases of Bax/Bcl-2 ratio and levels of cleaved caspase 3. Treatments of the cells with UPAs resulted in an increase in G2/M cell cycle arrest. Cytotoxic effects of 5-FU against MDA-MB-231 cells were enhanced by UPAs. The combination treatment of UPAs and 5-FU for 48 h elicited a synergistic cytotoxic effect on MDA-MB-231 cells. Altogether, these data suggest that UPAs are potential therapeutic agents for breast cancer.

Nanomedicine applications in the treatment of breast cancer: current state of the art

Breast cancer is the most common malignant disease in women worldwide, but the current drug therapy is far from optimal as indicated by the high death rate of breast cancer patients. Nanomedicine is a promising alternative for breast cancer treatment. Nanomedicine products such as Doxil^® and Abraxane^® have already been extensively used for breast cancer adjuvant therapy with favorable clinical outcomes. However, these products were originally designed for generic anticancer purpose and not specifically for breast cancer treatment. With better understanding of the molecular biology of breast cancer, a number of novel promising nanotherapeutic strategies and devices have been developed in recent years. In this review, we will first give an overview of the current breast cancer treatment and the updated status of nanomedicine use in clinical setting, then discuss the latest important trends in designing breast cancer nanomedicine, including passive and active cancer cell targeting, breast cancer stem cell targeting, tumor microenvironment-based nanotherapy and combination nanotherapy of drug-resistant breast cancer. Researchers may get insight from these strategies to design and develop nanomedicine that is more tailored for breast cancer to achieve further improvements in cancer specificity, antitumorigenic effect, antimetastasis effect and drug resistance reversal effect.

Cancer drug delivery in the nano era: An overview and perspectives (Review)

Nanomaterials are increasingly used as drug carriers for cancer therapy. Nanomaterials also appeal to researchers in the areas of cancer diagnosis and biomarker discovery. Several antitumor nanodrugs are currently being tested in preclinical and clinical trials and show promise in therapeutic and other settings. We review the development of nanomaterial drug carriers, including liposomes, polymer nanoparticles, dendritic polymers, and nanomicelles, for the diagnosis and treatment of various cancers. The prospects of nanomaterials as drug carriers for future clinical applications are also discussed.

Use of liposomal doxorubicin for adjuvant chemotherapy of breast cancer in clinical practice

Breast cancer is one of the malignant tumors with the highest morbidity and mortality. It is helpful to reduce the rate of tumor recurrence and metastasis by treating breast cancer with adjuvant chemotherapy, so as to increase the cure rate or survival of patients. In recent years, liposomes have been regarded as a kind of new carrier for targeted drugs. Being effective for enhancing drug efficacy and reducing side effects, they have been widely used for developing anticancer drugs. As a kind of anthracycline with high anticancer activity, doxorubicin can treat or alleviate a variety of malignant tumors effectively when it is used on its own or in combination with other anticancer drugs. Although liposomal doxorubicin has been extensively used in the adjuvant chemotherapy of breast cancer, its exact therapeutic efficacy and side effects have not been definitely proven. Various clinical studies have adopted different combined regimes, dosages, and staging, so their findings differ to certain extent. This paper reviews the clinical application of liposomal doxorubicin in the adjuvant chemotherapy of breast cancer and illustrates therapeutic effects and side effects of pegylated liposomal doxorubicin (PLD) and non-PLD (NPLD) in clinical research, in order to discuss the strategies for applying these drugs in such adjuvant chemotherapy, looking forward to providing references for related research and clinical treatment in terms of dosage, staging, combined regimes, and analysis methods and so on.

In Vivo Tracking of Chemokine Receptor CXCR4-Engineered Mesenchymal Stem Cell Migration by Optical Molecular Imaging

CXCR4, the stromal cell-derived factor-1 receptor, plays an important role in the migration of hematopoietic progenitor/stem cells to injured and inflamed areas. Noninvasive cell tracking methods could be useful for monitoring cell fate. Therefore, in this study, we evaluated the efficacy of an intravenous infusion of genetically engineered mesenchymal stem cells (MSCs) overexpressing CXC chemokine receptor 4 (CXCR4) to home to the tumor, by optical imaging. We constructed a retroviral vector containing CXCR with dual reporter genes, eGFP and Fluc2, under the control of an EF1α promoter (pBABE-EF1α-CXCR4-eGFP-IRES-Fluc2). We also developed an eGFP-Fluc2 construct in the Retro-X retroviral vector (Retro-X-eGFP-Fluc2). MSCs were transduced with retroviruses to generate CXCR4-overexpressing MSCs (MSC-CXCR4/Fluc2) and MSCs (MSC/Fluc2). CXCR4 mRNA and protein expression was confirmed by RT-PCR and Western blotting, respectively, and it was higher in MSC-CXCR4/Fluc2 than in naive MSCs. eGFP expression was confirmed by confocal microscopy. The transfected MSC-CXCR4/Fluc2 cells showed higher migratory capacity than naive MSCs observed in Transwell migration assay. The in vivo migration of CXCR4-overexpressing MSCs to MDAMB231/Rluc tumor model by BLI imaging was also confirmed. Intravenous delivery of genetically modified MSCs overexpressing CXCR4 with a Fluc2 reporter gene may be a useful, noninvasive BLI imaging tool for tracking cell fate.

An Abraded Surface of Doxorubicin-Loaded Surfactant-Containing Drug Delivery Systems Effectively Reduces the Survival of Carcinoma Cells

An effective antitumor remedy is yet to be developed. All previous approaches for a targeted delivery of anticancer medicine have relied on trial and error. The goal of this study was to use structural insights gained from the study of delivery systems and malignant cells to provide for a systematic approach to the development of next-generation drugs. We used doxorubicin (Dox) liposomal formulations. We assayed for cytotoxicity via the electrical current exclusion method. Dialysis of the samples yielded information about their drug release profiles. Information about the surface of the delivery systems was obtained through synchrotron small-angle X-ray scattering (SAXS) measurements. SAXS measurements revealed that Dox-loading yielded an abraded surface of our Dox liposomal formulation containing soybean oil, which also correlated with an effective reduction of the survival of carcinoma cells. Furthermore, a dialysis assay revealed that a higher burst of Dox was released from soybean oil-containing preparations within the first five hours. We conclude from our results that an abraded surface of Dox-loaded drug delivery system increases their efficacy. The apparent match between surface geometry of drug delivery systems and target cells is suggested as a steppingstone for refined development of drug delivery systems. This is the first study to provide a systematic approach to developing next-generation drug carrier systems using structural insights to guide the development of next-generation drug delivery systems with increased efficacy and reduced side effects.

Organic nanoparticle systems for spatiotemporal control of multimodal chemotherapy

INTRODUCTION

Chemotherapeutic drugs are used in combination to target multiple mechanisms involved in cancer cell survival and proliferation. Carriers are developed to deliver drug combinations to common target tissues in optimal ratios and desirable sequences. Nanoparticles (NP) have been a popular choice for this purpose due to their ability to increase the circulation half-life and tumor accumulation of a drug. Areas covered: We review organic NP carriers based on polymers, proteins, peptides, and lipids for simultaneous delivery of multiple anticancer drugs, drug/sensitizer combinations, drug/photodynamic therapy or drug/photothermal therapy combinations, and drug/gene therapeutics with examples in the past three years. Sequential delivery of drug combinations, based on either sequential administration or built-in release control, is introduced with an emphasis on the mechanistic understanding of such control. Expert opinion: Recent studies demonstrate how a drug carrier can contribute to co-localizing drug combinations in optimal ratios and dosing sequences to maximize the synergistic effects. We identify several areas for improvement in future research, including the choice of drug combinations, circulation stability of carriers, spatiotemporal control of drug release, and the evaluation and clinical translation of combination delivery.

DOXIL when combined with Withaferin A (WFA) targets ALDH1 positive cancer stem cells in ovarian cancer

Ovarian cancer is a highly aggressive and deadly disease. Currently, the treatment for ovarian cancer entails cytoreductive surgery followed by chemotherapy, mainly cisplatin or carboplatin combined with paclitaxel. Although this regimen is initially effective in a high percentage of cases, unfortunately, after few months of initial treatment, tumor relapse occurs due to platinum-resistance. DOXIL (liposomal preparation of doxorubicin) is a choice of drug for recurrent ovarian cancer. However, its response rate is very low and is accompanied by myocardial toxicity. Resistance to chemotherapy and recurrence of cancer is primarily attributed to the presence of cancer stem cells (CSCs), a small population of cells present in cancer. Effect of DOXIL and withaferin A (WFA), both alone and in combination, was investigated on cell proliferation of ovarian cancer cell line A2780 and tumor growth in SCID mice bearing i.p. ovarian tumors. ALDH1 cells were isolated from A2780 using cell sorter, and effect of DOXIL and WFA both alone and in combination on tumorigenic function of ALDH1 was studied using spheroids formation assays in vitro. Western blots were performed to examine the expression of ALDH1 and Notch 1 genes. In our studies, we showed, for the first time, that DOXIL when combined with withaferin A (WFA) elicits synergistic effect on inhibition of cell proliferation of ovarian cancer cells and inhibits the expression of ALDH1 protein, a marker for ALDH1 positive cancer stem cells (CSCs), and Notch1, a signaling pathway gene required for self-renewal of CSCs. Inhibition of expression of both ALDH1 and Notch1 genes by WFA was found to be dose dependent, whereas DOXIL (200 nM) was found to be ineffective. SCID mice, bearing i.p. ovarian tumors, were treated with a small dose of DOXIL (2 mg/kg) in combination with a sub-optimal dose of WFA (2 mg/kg) which resulted in a highly significant (60% to 70%) reduction in tumor growth, and complete inhibition of metastasis compared to control. In contrast, WFA treatment showed a significant reduction in tumor growth but no change in metastasis compared to control. DOXIL showed non-significant reduction in tumor growth and no change in metastasis compared to control. Isolated ALDH1 positive CSCs treated with the combination of DOXIL and WFA resulted in a significant reduction in spheroids formation (tumorigenic function of CSCs) and expression of ALDH1 protein. WFA when used alone at a concentration of 1.5 μM was found to be highly effective in suppression of ALDH1 expression, whereas DOXIL at a concentration of 200 nM was found to be ineffective. DOXIL in combination with WFA elicits synergistic effects, targets cancer stem cells, and has potential to minimize induction of drug resistance and reoccurrence of cancer. Based on our studies, we conclude that the combination of DOXIL with WFA has the potential to be an effective therapy for ovarian cancer and may ameliorate DOXIL related side effects as well as recurrence of ovarian cancer leading to increase in patients' survival rate.