Inhibition of breast cancer with transdermal tamoxifen-encapsulated lipoplex

Application of biomacromolecule-based passive penetration enhancement technique in superficial tumor therapy: A review

Transdermal drug delivery (TDD) has shown great promise in superficial tumor therapy due to its noninvasive and avoidance of the first-pass effect. Especially, passive penetration enhancement technique (PPET) provides the technical basis for TDD by temporarily altering the skin surface structure without requiring external energy. Biomacromolecules and their derived nanocarriers offer a wide range of options for PPET development, with outstanding biocompatibility and biodegradability. Furthermore, the abundant functional groups on biomacromolecule surfaces can be modified to yield functional materials capable of targeting specific sites and responding to stimuli. This enables precise drug delivery to the tumor site and controlled drug release, with the potential to replace traditional drug delivery methods and make PPET-related personalized medicine a reality. This review focuses on the mechanism of biomacromolecules and nanocarriers with skin, and the impact of nanocarriers' surface properties of nanocarriers on PPET efficiency. The applications of biomacromolecule-based PPET in superficial tumor therapy are also summarized. In addition, the advantages and limitations are discussed, and their future trends are projected based on the existing work of biomacromolecule-based PPET.

A landscape of recent advances in lipid nanoparticles and their translational potential for the treatment of solid tumors

Lipid nanoparticles (LNPs) are biocompatible drug delivery systems that have found numerous applications in medicine. Their versatile nature enables the encapsulation and targeting of various types of medically relevant molecular cargo, including oligonucleotides, proteins, and small molecules for the treatment of diseases, such as cancer. Cancers that form solid tumors are particularly relevant for LNP-based therapeutics due to the enhanced permeation and retention effect that allows nanoparticles to accumulate within the tumor tissue. Additionally, LNPs can be formulated for both locoregional and systemic delivery depending on the tumor type and stage. To date, LNPs have been used extensively in the clinic to reduce systemic toxicity and improve outcomes in cancer patients by encapsulating chemotherapeutic drugs. Next-generation lipid nanoparticles are currently being developed to expand their use in gene therapy and immunotherapy, as well as to enable the co-encapsulation of multiple drugs in a single system. Other developments include the design of targeted LNPs to specific cells and tissues, and triggerable release systems to control cargo delivery at the tumor site. This review paper highlights recent developments in LNP drug delivery formulations and focuses on the treatment of solid tumors, while also discussing some of their current translational limitations and potential opportunities in the field.

Breaking barriers: bilosomes gel potentials to pave the way for transdermal breast cancer treatment with Tamoxifen

OBJECTIVE

Breast cancer affects women globally, regardless of age or location. On the other hand, Tamoxifen (TXN), a class II biopharmaceutical drug is acting as a prophylactic/treating agent for women at risk of and/or with hormone receptor-positive breast cancer. However, its oral administration has life-threatening side effects, which have led researchers to investigate alternative delivery methods. One such method is transdermal drug delivery utilizing bile salts as penetration enhancers, aka Bilosomes.

METHODS

Bilosomes formulations were optimized statistically for the outcome of vesicle shape, size, and entrapment efficiency using two types of bile, i.e. sodium taurocholate and sodium cholate. These bilosomes were then loaded into HPMC base gel and further characterized for their morphology, drug content, pH, viscosity, spreadability and eventually ex-vivo skin penetration and deposition studies.

RESULTS

Findings showed that sodium cholate has superiority as a penetration enhancer over sodium taurocholate in terms of morphological characterizes, zeta potential, and cumulative amounts of tamoxifen permeated per unit area (15.13 ± 0.71 μg/cm2 and 6.51 ± 0.6 μg/cm2 respectively). In fact, bilosomes designed with sodium cholate provided around 9 folds of skin deposition compared to TXN non-bilosomal gel.

CONCLUSION

Bilosomes gels could be a promising option for locally delivering tamoxifen to the breast through the skin, offering an encouraging transdermal solution.

A flexible liposomal polymer complex as a platform of specific and regulable immune regulation for individual cancer immunotherapy

BACKGROUND

The applicability and therapeutic efficacy of specific personalized immunotherapy for cancer patients is limited by the genetic diversity of the host or the tumor. Side-effects such as immune-related adverse events (IRAEs) derived from the administration of immunotherapy have also been observed. Therefore, regulatory immunotherapy is required for cancer patients and should be developed.

METHODS

The cationic lipo-PEG-PEI complex (LPPC) can stably and irreplaceably adsorb various proteins on its surface without covalent linkage, and the bound proteins maintain their original functions. In this study, LPPC was developed as an immunoregulatory platform for personalized immunotherapy for tumors to address the barriers related to the heterogenetic characteristics of MHC molecules or tumor associated antigens (TAAs) in the patient population. Here, the immune-suppressive and highly metastatic melanoma, B16F10 cells were used to examine the effects of this platform. Adsorption of anti-CD3 antibodies, HLA-A2/peptide, or dendritic cells' membrane proteins (MP) could flexibly provide pan-T-cell responses, specific Th1 responses, or specific Th1 and Th2 responses, depending on the host needs. Furthermore, with regulatory antibodies, the immuno-LPPC complex properly mediated immune responses by adsorbing positive or negative antibodies, such as anti-CD28 or anti-CTLA4 antibodies.

RESULTS

The results clearly showed that treatment with LPPC/MP/CD28 complexes activated specific Th1 and Th2 responses, including cytokine release, CTL and prevented T-cell apoptosis. Moreover, LPPC/MP/CD28 complexes could eliminate metastatic B16F10 melanoma cells in the lung more efficiently than LPPC/MP. Interestingly, the melanoma resistance of mice treated with LPPC/MP/CD28 complexes would be reversed to susceptible after administration with LPPC/MP/CTLA4 complexes. NGS data revealed that LPPC/MP/CD28 complexes could enhance the gene expression of cytokine and chemokine pathways to strengthen immune activation than LPPC/MP, and that LPPC/MP/CTLA4 could abolish the LPPC/MP complex-mediated gene expression back to un-treatment.

CONCLUSIONS

Overall, we proved a convenient and flexible immunotherapy platform for developing personalized cancer therapy.

Transdermal nanolipoplex simultaneously inhibits subcutaneous melanoma growth and suppresses systemically metastatic melanoma by activating host immunity

Benefit for clinical melanoma treatments, the transdermal neoadjuvant therapy could reduce surgery region and increase immunotherapy efficacy. Using lipoplex (Lipo-PEG-PEI-complex, LPPC) encapsulated doxorubicin (DOX) and carrying CpG oligodeoxynucleotide; the transdermally administered nano-liposomal drug complex (LPPC-DOX-CpG) would have high cytotoxicity and immunostimulatory activity to suppress systemic metastasis of melanoma. LPPC-DOX-CpG dramatically suppressed subcutaneous melanoma growth by inducing tumor cell apoptosis and recruiting immune cells into the tumor area. Animal studies further showed that the colonization and growth of spontaneously metastatic melanoma cells in the liver and lung were suppressed by transdermal LPPC-DOX-CpG. Furthermore, NGS analysis revealed IFN-γ and NF-κB pathways were triggered to recruit and activate the antigen-presenting-cells and effecter cells, which could activate the anti-tumor responses as the major mechanism responsible for the therapeutic effect of LPPC-DOX-CpG. Finally, we have successfully proved transdermal LPPC-DOX-CpG as a promising penetrative carrier to activate systemic anti-tumor immunity against subcutaneous and metastatic tumor.

Mineral medicine: from traditional drugs to multifunctional delivery systems

Mineral drugs are an important constituent of traditional Chinese medicine (TCM). Taking minerals that contain heavy metals as drugs is a very national characteristic part of TCM. However, the safety and scientific nature of mineral drugs are controversial owing to their heavy metals and strong toxicity. In 2000, the Food and Drug Administration (FDA) authorized arsenic trioxide (ATO) as first-line therapy for acute promyelocytic leukemia. This makes the development and utilization of mineral drugs become a research hotspot. The development of nanomedicine has found a great prospect of mineral drugs in nano-delivery carriers. And that will hold promise to address the numerous biological barriers facing mineral drug formulations. However, the studies on mineral drugs in the delivery system are few at present. There is also a lack of a detailed description of mineral drug delivery systems. In this review, the advanced strategies of mineral drug delivery systems in tumor therapy are summarized. In addition, the therapeutic advantages and research progress of novel mineral drug delivery systems are also discussed. Here, we hope that this will provide a useful reference for the design and application of new mineral drug delivery systems.

Current understandings and clinical translation of nanomedicines for breast cancer therapy

Breast cancer is one of the most frequently diagnosed cancers that is threatening women's life. Current clinical treatment regimens for breast cancer often involve neoadjuvant and adjuvant systemic therapies, which somewhat are associated with unfavorable features. Also, the heterogeneous nature of breast cancers requires precision medicine that cannot be fulfilled by a single type of systemically administered drug. Taking advantage of the nanocarriers, nanomedicines emerge as promising therapeutic agents for breast cancer that could resolve the defects of drugs and achieve precise drug delivery to almost all sites of primary and metastatic breast tumors (e.g. tumor vasculature, tumor stroma components, breast cancer cells, and some immune cells). Seven nanomedicines as represented by Doxil® have been approved for breast cancer clinical treatment so far. More nanomedicines including both non-targeting and active targeting nanomedicines are being evaluated in the clinical trials. However, we have to realize that the translation of nanomedicines, particularly the active targeting nanomedicines is not as successful as people have expected. This review provides a comprehensive landscape of the nanomedicines for breast cancer treatment, from laboratory investigations to clinical applications. We also highlight the key advances in the understanding of the biological fate and the targeting strategies of breast cancer nanomedicine and the implications to clinical translation.

Transdermal Drug delivery: A step towards treatment of cancer

BACKGROUND

Transdermal drug delivery is an emerging and tempting system over oral and hypodermic drug delivery system. With the new developments in skin penetration techniques, anticancer drugs ranging from hydrophilic macromolecules to lipophilic drugs can be administered via transdermal route to treat cancer.

OBJECTIVE

In the present review, various approaches to enhance the transdermal delivery of drugs is discussed including the micro and nanotechnology based transdermal formulations like chemotherapy, gene therapy, immunotherapy, phototherapy, vaccines and medical devices. Limitations and advantages of various transdermal technologies is also elaborated.

METHOD

In this review, patent applications and recent literature of transdermal drug delivery systems employed to cure mainly cancer are covered.

RESULTS

Transdermal drug delivery systems have proved their potential to cure cancer. They increase the bioavailability of drug by site specific drug delivery and can reduce the side effects/toxicity associated with anticancer drugs.

CONCLUSION

The potential of transdermal drug delivery systems to carry the drug may unclutter novel ways for therapeutic intercessions in various tumors.

Lipid Nanoparticulate Drug Delivery Systems: Recent Advances in the Treatment of Skin Disorders

The multifunctional role of the human skin is well known. It acts as a sensory and immune organ that protects the human body from harmful environmental impacts such as chemical, mechanical, and physical threats, reduces UV radiation effects, prevents moisture loss, and helps thermoregulation. In this regard, skin disorders related to skin integrity require adequate treatment. Lipid nanoparticles (LN) are recognized as promising drug delivery systems (DDS) in treating skin disorders. Solid lipid nanoparticles (SLN) together with nanostructured lipid carriers (NLC) exhibit excellent tolerability as these are produced from physiological and biodegradable lipids. Moreover, LN applied to the skin can improve stability, drug targeting, occlusion, penetration enhancement, and increased skin hydration compared with other drug nanocarriers. Furthermore, the features of LN can be enhanced by inclusion in suitable bases such as creams, ointments, gels (i.e., hydrogel, emulgel, bigel), lotions, etc. This review focuses on recent developments in lipid nanoparticle systems and their application to treating skin diseases. We point out and consider the reasons for their creation, pay attention to their advantages and disadvantages, list the main production techniques for obtaining them, and examine the place assigned to them in solving the problems caused by skin disorders.

Topical transdermal chemoprevention of breast cancer: where will nanomedical approaches deliver us?

Despite the high incidence of breast cancer, there are few pharmacological prevention strategies for the high-risk population and those that are available have low adherence. Strategies that deliver drugs directly to the breasts may increase drug local concentrations, improving efficacy, safety and acceptance. The skin of the breast has been proposed as an administration route for local transdermal therapy, which may improve drug levels in the mammary tissue, due to both deep local penetration and percutaneous absorption. In this review, we discuss the application of nanotechnology-based strategies for the delivery of well established and new agents as well as drug repurposing using the topical transdermal route to improve the outcomes of preventive therapy for breast cancer.

Transdermal Delivery of Chemotherapeutics: Strategies, Requirements, and Opportunities

Chemotherapeutic drugs are primarily administered to cancer patients via oral or parenteral routes. The use of transdermal drug delivery could potentially be a better alternative to decrease the dose frequency and severity of adverse or toxic effects associated with oral or parenteral administration of chemotherapeutic drugs. The transdermal delivery of drugs has shown to be advantageous for the treatment of highly localized tumors in certain types of breast and skin cancers. In addition, the transdermal route can be used to deliver low-dose chemotherapeutics in a sustained manner. The transdermal route can also be utilized for vaccine design in cancer management, for example, vaccines against cervical cancer. However, the design of transdermal formulations may be challenging in terms of the conjugation chemistry of the molecules and the sustained and reproducible delivery of therapeutically efficacious doses. In this review, we discuss the nano-carrier systems, such as nanoparticles, liposomes, etc., used in recent literature to deliver chemotherapeutic agents. The advantages of transdermal route over oral and parenteral routes for popular chemotherapeutic drugs are summarized. Furthermore, we also discuss a possible in silico approach, Formulating for Efficacy™, to design transdermal formulations that would probably be economical, robust, and more efficacious.

Positively Charged Nanoparticle Delivery of n-Butylidenephthalide Enhances Antitumor Effect in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the second and sixth leading cause of cancer death in men and woman in 185 countries statistics, respectively. n-Butylidenephthalide (BP) has shown anti-HCC activity, but it also has an unstable structure that decreases its potential antitumor activity. The aim of this study was to investigate the cell uptake, activity protection, and antitumor mechanism of BP encapsulated in the novel liposome LPPC in HCC cells. BP/LPPC exhibited higher cell uptake and cytotoxicity than BP alone, and combined with clinical drug etoposide (VP-16), BP/LPPC showed a synergistic effect against HCC cells. Additionally, BP/LPPC increased cell cycle regulators (p53, p-p53, and p21) and decreased cell cycle-related proteins (Rb, p-Rb, CDK4, and cyclin D1), leading to cell cycle arrest at the G₀/G₁ phase in HCC cells. BP/LPPC induced cell apoptosis through activation of both the extrinsic (Fas-L and Caspase-8) and intrinsic (Bax and Caspase-9) apoptosis pathways and activated the caspase cascade to trigger HCC cell death. In conclusion, the LPPC complex improved the antitumor activity of BP in terms of cytotoxicity, cell cycle regulation and cell apoptosis, and BP/LPPC synergistically inhibited cell growth during combination treatment with VP-16 in HCC cells. Therefore, BP/LPPC is potentially a good candidate for clinical drug development or for use as an adjuvant for clinical drugs as a combination therapy for hepatocellular carcinoma.

Enhancement of cytotoxicity and induction of apoptosis by cationic nano-liposome formulation of n-butylidenephthalide in breast cancer cells

Breast cancer is the second most common malignancy in women. Current clinical therapy for breast cancer has many disadvantages, including metastasis, recurrence, and poor quality of life. Furthermore, it is necessary to find a new therapeutic drug for breast cancer patients to meet clinical demand. n-Butylidenephthalide (BP) is a natural and hydrophobic compound that can inhibit several tumors. However, BP is unstable in aqueous or protein-rich environments, which reduces the activity of BP. Therefore, we used an LPPC (Lipo-PEG-PEI complex) that can encapsulate both hydrophobic and hydrophilic compounds to improve the limitation of BP. The purpose of this study is to investigate the anti-tumor mechanisms of BP and BP/LPPC and further test the efficacy of BP encapsulated by LPPC on SK-BR-3 cells. BP inhibited breast cancer cell growth, and LPPC encapsulation (BP/LPPC complex) enhanced the cytotoxicity on breast cancer by stabilizing the BP activity and offering endocytic pathways. Additionally, BP and LPPC-encapsulated BP induced cell cycle arrest at the G₀/G₁ phase and might trigger both extrinsic as well as intrinsic cell apoptosis pathway, resulting in cell death. Moreover, the BP/LPPC complex had a synergistic effect with doxorubicin of enhancing the inhibitory effect on breast cancer cells. Consequently, LPPC-encapsulated BP could improve the anti-cancer effects on breast cancer in vitro. In conclusion, BP exhibited an anti-cancer effect on breast cancer cells, and LPPC encapsulation efficiently improved the cytotoxicity of BP via an acceleration of entrapment efficiency to induce cell cycle block and apoptosis. Furthermore, BP/LPPC exhibited a synergistic effect in combination with doxorubicin.

Enhanced anticancer activity and endocytic mechanisms by polymeric nanocarriers of n-butylidenephthalide in leukemia cells

PURPOSE

The purpose of this study was to investigate the antitumor mechanisms of n-butylidenephthalide (BP) and to further examine the delivery efficacy of polycationic liposome containing PEI and polyethylene glycol complex (LPPC)-encapsulated BP in leukemia cells.

METHODS

MTS, flow cytometric and TUNEL assays were performed to assess cell viability and apoptosis. BP and BP/LPPC complex delivery efficiency was analyzed by full-wavelength fluorescent scanner and fluorescence microscope. The expressions of cell cycle- and apoptosis-related proteins were conducted by Western blotting.

RESULTS

The results showed that BP inhibited leukemia cell growth by inducing cell cycle arrest and cell apoptosis. LPPC-encapsulated BP rapidly induced endocytic pathway activation, resulting in the internalization of BP into leukemia cells, causing cell apoptosis within 1 h.

CONCLUSIONS

LPPC encapsulation enhanced the cytotoxic activity of BP and did not influence the effects of BP induction that suggested LPPC-encapsulated BP might be developed as anti-leukemia drugs in future.

Antitumor Effects of N-Butylidenephthalide Encapsulated in Lipopolyplexs in Colorectal Cancer Cells

Colorectal cancer (CRC) is the third most common type of cancer and the second most common cause of cancer-related death in the world. N-Butylidenephthalide (BP), a natural compound, inhibits several cancers, such as hepatoma, brain tumor and colon cancer. However, due to the unstable structure, the activity of BP is quickly lost after dissolution in an aqueous solution. A polycationic liposomal polyethylenimine and polyethylene glycol complex (LPPC), a new drug carrier, encapsulates both hydrophobic and hydrophilic compounds, maintains the activity of the compound, and increases uptake of cancer cells. The purpose of this study is to investigate the antitumor effects and protection of BP encapsulated in LPPC in CRC cells. The LPPC encapsulation protected BP activity, increased the cytotoxicity of BP and enhanced cell uptake through clathrin-mediated endocytosis. Moreover, the BP/LPPC-regulated the expression of the p21 protein and cell cycle-related proteins (CDK4, Cyclin B1 and Cyclin D1), resulting in an increase in the population of cells in the G₀/G₁ and subG₁ phases. BP/LPPC induced cell apoptosis by activating the extrinsic (Fas, Fas-L and Caspase-8) and intrinsic (Bax and Caspase-9) apoptosis pathways. Additionally, BP/LPPC combined with 5-FU synergistically inhibited the growth of HT-29 cells. In conclusion, LPPC enhanced the antitumor activity and cellular uptake of BP, and the BP/LPPC complex induced cell cycle arrest and apoptosis, thereby causing death. These findings suggest the putative use of BP/LPPC as an adjuvant cytotoxic agent for colorectal cancer.

Novel Tamoxifen Nanoformulations for Improving Breast Cancer Treatment: Old Wine in New Bottles

Breast cancer (BC) is one of the leading causes of death from cancer in women; second only to lung cancer. Tamoxifen (TAM) is a hydrophobic anticancer agent and a selective estrogen modulator (SERM), approved by the FDA for hormone therapy of BC. Despite having striking efficacy in BC therapy, concerns regarding the dose-dependent carcinogenicity of TAM still persist, restricting its therapeutic applications. Nanotechnology has emerged as one of the most important strategies to solve the issue of TAM toxicity, owing to the ability of nano-enabled-formulations to deliver smaller concentrations of TAM to cancer cells, over a longer period of time. Various TAM-containing-nanosystems have been successfully fabricated to selectively deliver TAM to specific molecular targets found on tumour membranes, reducing unwanted toxic effects. This review begins with an outline of breast cancer, the current treatment options and a history of how TAM has been used as a combatant of BC. A detailed discussion of various nanoformulation strategies used to deliver lower doses of TAM selectively to breast tumours will then follow. Finally, a commentary on future perspectives of TAM being employed as a targeting vector, to guide the delivery of other therapeutic and diagnostic agents selectively to breast tumours will be presented.

Encapsulated n-Butylidenephthalide Efficiently Crosses the Blood-Brain Barrier and Suppresses Growth of Glioblastoma

Background

n-Butylidenephthalide (BP) has anti-tumor effects on glioblastoma. However, the limitation of BP for clinical application is its unstable structure. A polycationic liposomal polyethylenimine (PEI) and polyethylene glycol (PEG) complex (LPPC) has been developed to encapsulate BP for drug structure protection. The purpose of this study was to investigate the anti-cancer effects of the BP/LPPC complex on glioblastoma in vitro and in vivo.

Methods

DBTRG-05MG tumor bearing xenograft mice were treated with BP and BP/LPPC and then their tumor sizes, survival, drug biodistribution were measured. RG2 tumor bearing F344 rats also treated with BP and BP/LPPC and then their tumor sizes by magnetic resonance imaging for evaluation blood–brain barrier (BBB) across and drug therapeutic effects. After treated with BP/LPPC in vitro, cell uptake, cell cycle and apoptotic regulators were analyzed for evaluation the therapeutic mechanism.

Results

In athymic mice, BP/LPPC could efficiently suppress tumor growth and prolong survival. In F334 rats, BP/LPPC crossed the BBB and led to tumor shrinkage. BP/LPPC promoted cell cycle arrest at the G₀/G₁ phase and triggered the extrinsic and intrinsic cell apoptosis pathways resulting cell death. BP/LPPC also efficiently suppressed VEGF, VEGFR1, VEGFR2, MMP2 and MMP9 expression.

Conclusion

BP/LPPC was rapidly and efficiently transported to the tumor area across the BBB and induced cell apoptosis, anti-angiogenetic and anti-metastatic effects in vitro and in vivo.

Inhibition of 3β-Hydroxysteroid Dehydrogenase Type 1 Suppresses Interleukin-6 in Breast Cancer

BACKGROUND

Recently, we demonstrated that the expression of 3β-hydroxysteroid dehydrogenase type 1 (HSD3B1) in breast cancer is associated with shorter recurrence-free survival, and genetic or pharmacologic inhibition of HSD3B1 reduced colony formation and xenograft growth. However, the mechanisms are unclear.

METHODS

Triple-negative MDA-MB-231 and BT-20 breast cancer cells underwent HSD3B1 silencing. Microarray and bioinformatic analysis were performed. The interleukin-6 (IL-6) expression and secretion were evaluated using real-time quantitative polymerase chain reaction and enzyme-linked immunosorbent assay. Clonogenic ability and cell viability were determined in the absence or presence of recombinant IL-6.

RESULTS

Functional and pathway enrichment analyses showed that HSD3B1 silencing modulates the expression of several growth factors and cytokines. Cells transfected with HSD3B1-targeting small interfering RNA or treated with an HSD3B1 inhibitor (trilostane) had decreased IL-6 expression and secretion. HSD3B1 inhibition reduced colony formation, which was partially rescued by IL-6 supplementation. The HSD3B1 knockdown enhanced paclitaxel sensitivity, and IL-6 treatment partially reversed the augmented cytotoxicity.

CONCLUSIONS

Our findings suggest that the therapeutic potential of targeting HSD3B1 is in part mediated by IL-6 suppression.

Antitumor Effect of n-Butylidenephthalide Encapsulated on B16/F10 Melanoma Cells In Vitro with a Polycationic Liposome Containing PEI and Polyethylene Glycol Complex

Advanced melanoma can metastasize to distal organs from the skin and yield an aggressive disease and poor prognosis even after treatment with chemotherapeutic agents. The compound n-Butylidenephthalide (BP) is isolated from Angelica sinensis, which is used to treat anemia and gynecological dysfunction in traditional Chinese medicine. Studies have indicated that BP can inhibit cancers, including brain, lung, prostate, liver, and colon cancers. However, because BP is a natural hydrophobic compound, it is quickly metabolized by the liver within 24 h, and thus has limited potential for development in cancer therapy. This study investigated the anticancer mechanisms of BP through encapsulation with a novel polycationic liposome containing polyethylenimine (PEI) and polyethylene glycol complex (LPPC) in melanoma cells. The results demonstrated that BP/LPPC had higher cytotoxicity than BP alone and induced cell cycle arrest at the G₀/G₁ phase in B16/F10 melanoma cells. The BP/LPPC-treated cell indicated an increase in subG₁ percentage and TUNEL positive apoptotic morphology through induction of extrinsic and intrinsic apoptosis pathways. The combination of BP and LPPC and clinical drug 5-Fluorouracil had a greater synergistic inhibition effect than did a single drug. Moreover, LPPC encapsulation improved the uptake of BP values through enhancement of cell endocytosis and maintained BP cytotoxicity activity within 24 h. In conclusion, BP/LPPC can inhibit growth of melanoma cells and induce cell arrest and apoptosis, indicating that BP/LPPC has great potential for development of melanoma therapy agents.

Temperature-sensitive liposomes for co-delivery of tamoxifen and imatinib for synergistic breast cancer treatment

Co-delivery of chemotherapeutic agents using nanocarriers is a promising strategy for enhancing therapeutic efficacy of anticancer agents. The aim of this work was to develop tamoxifen and imatinib dual drug loaded temperature-sensitive liposomes to treat breast cancer. Liposomes were prepared using 1, 2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), monopalmitoyl-2-hydroxy-sn-glycero-3-phosphocholine (MPPC), and different surface active agents. The liposomes were characterized for the average particle size, zeta potential, transition temperature, and drug release below and above liposomal transition temperature. The temperature-sensitive liposomes co-encapsulated with tamoxifen and imatinib were investigated for their synergistic activity against MCF-7 and MDA-MB-231 breast cancer cells. The liposomal nanoparticles showed a transition temperature of 39.4 °C and >70% encapsulation efficiency for tamoxifen and imatinib. The temperature-responsive liposomes showed more than 80% drug released within 30 min above transition temperature. Dual drug loaded liposomes showed synergistic growth inhibition against MCF-7 and MDA-MB-231 breast cancer cells. Co-delivery of tamoxifen and imatinib using temperature-sensitive liposomes can be developed as a potential targeting strategy against breast cancer.

Engineered nanomaterials and human health: Part 2. Applications and nanotoxicology (IUPAC Technical Report)

Research on engineered nanomaterials (ENM) has progressed rapidly from the very early stages of studying their unique, size-dependent physicochemical properties and commercial exploration to the development of products that influence our everyday lives. We have previously reviewed various methods for synthesis, surface functionalization, and analytical characterization of ENM in a publication titled ‘Engineered Nanomaterials: Preparation, Functionalization and Characterization’. In this second, inter-linked document, we first provide an overview of important applications of ENM in products relevant to human healthcare and consumer goods, such as food, textiles, and cosmetics. We then highlight the challenges for the design and development of new ENM for bio-applications, particularly in the rapidly developing nanomedicine sector. The second part of this document is dedicated to nanotoxicology studies of ENM in consumer products. We describe the various biological targets where toxicity may occur, summarize the four nanotoxicology principles, and discuss the need for careful consideration of the biodistribution, degradation, and elimination routes of nanosized materials before they can be safely used. Finally, we review expert opinions on the risk, regulation, and ethical aspects of using engineered nanomaterials in applications that may have direct or indirect impact on human health or our environment.

Solid lipid nanoparticles: Reversal of tamoxifen resistance in breast cancer

The objective of the present study was to investigate the effect of tamoxifen (Tam) loaded solid lipid nanoparticles (SLNs) on MCF7 Tam-resistant breast cancer cells (MCF7-TamR). Tam-SLNs were produced by the hot homogenization method. The characterization studies of Tam-SLNs demonstrated good physical stability with small particle size. The in vitro cytotoxicity results showed that Tam-SLNs enhanced the efficacy of Tam and reversed the acquired Tam resistance by inducing apoptosis, altering the expression levels of specific miRNA and the related apoptosis-associated target-genes in both MCF7 and MCF7-TamR cells without damaging the MCF10A control cells (p < 0.05). In conclusion, we demonstrated a molecular mechanism of the induction of apoptosis by Tam-SLNs in MCF7 and MCF7-TamR cells, and thus, we demonstrated that Tam-SLNs were more effective than Tam. The present study suggests that the use SLNs may be a potential therapeutic strategy to overcome Tam-resistance in breast cancer for clinical use.

Significant role of cationic polymers in drug delivery systems

Cationic polymers are characterized as the macromolecules that possess positive charges, which can be either inherently in the polymer side chains and/or its backbone. Based on their origins, cationic polymers are divided in two category including natural and synthetic, in which the possessed positive charges are as result of primary, secondary or tertiary amine functional groups that could be protonated in particular situations. Cationic polymers have been employed commonly as drug delivery agents due to their superior encapsulation efficacy, enhanced bioavailability, low toxicity and improved release profile. In this paper, we focus on the most prominent examples of cationic polymers which have been revealed to be applicable in drug delivery systems and we also discuss their general synthesis and surface modification methods as well as their controlled release profile in drug delivery.

Biocompatible Phospholipid-Based Mixed Micelles for Tamoxifen Delivery: Promising Evidences from In - Vitro Anticancer Activity and Dermatokinetic Studies

Tamoxifen (TAM) is frequently prescribed for the management breast cancer, but is associated with the challenges like compromised aqueous solubility and poor bioavailability to the target site. It was envisioned to develop phospholipid-based mixed micelles to explore the promises offered by the biocompatible carriers. Various compositions were prepared, employing soya lecithin, polysorbate 80, sodium chloride/dextrose, and water, by self-assembled technique. The formulations were characterized for micromeritics and evaluated for in vitro drug release, hemolysis study, dermatokinetic studies on rodents, and cytotoxicity on MCF-7 cell lines. Cellular uptake of the system was also studied using confocal laser scanning microscopy. The selected composition was of sub-micron range (28.81 ± 2.1 nm), with spherical morphology. During in-vitro studies, the mixed micelles offered controlled drug release than that of conventional gel. Cytotoxicity was significantly enhanced and IC₅₀ value was reduced that of the naïve drug. The bioavailability in epidermis and dermis skin layers was enhanced approx. fivefold and threefold, respectively. The developed nanosystem not only enhanced the efficacy of the drug but also maintained the integrity of skin, as revealed by histological studies. The developed TAM-nanocarrier possesses potential promises for safe and better delivery of TAM.

A review on current nanomaterials and their drug conjugate for targeted breast cancer treatment

Breast cancer is the most common malignancy worldwide, especially among women, with substantial after-treatment effects. The survival rates of breast cancer have decreased over the years even with the existence of various therapeutic strategies, specifically, chemotherapy. Clinical drugs administered for breast cancer appear to be non-targeting to specific cancer sites leading to severe side effects and potentially harming healthy cells instead of just killing cancer cells. This leads to the need for designing a targeted drug delivery system. Nanomaterials, both organic and inorganic, are potential drug nanocarriers with the ability of targeting, imaging and tracking. Various types of nanomaterials have been actively researched together with their drug conjugate. In this review, we focus on selected nanomaterials, namely solid-lipid, liposomal, polymeric, magnetic nanoparticles, quantum dots, and carbon nanotubes and their drug conjugates, for breast cancer studies. Their advantages, disadvantages and previously conducted studies were highlighted.