The antitumor activity of tumor-homing peptide-modified thermosensitive liposomes containing doxorubicin on MCF-7/ADR: in vitro and in vivo

Cell penetrating peptides: Highlighting points in cancer therapy

Cell-penetrating peptides (CPPs), first identified in HIV a few decades ago, deserved great attention in the last two decades; especially to support the penetration of anticancer drug means. In the drug delivery discipline, they have been involved in various approaches from mixing with hydrophobic drugs to the use of genetically conjugated proteins. The early classification as cationic and amphipathic CPPs has been extended to a few more classes such as hydrophobic and cyclic CPPs so far. Developing potential sequences utilized almost all methods of modern science: choosing high-efficiency peptides from natural protein sequences, sequence-based comparison, amino acid substitution, obtaining chemical and/or genetic conjugations, in silico approaches, in vitro analysis, animal experiments, etc. The bottleneck effect in this discipline reveals the complications that modern science faces in drug delivery research. Most CPP-based drug delivery systems (DDSs) efficiently inhibited tumor volume and weight in mice, but only in rare cases reduced their levels and continued further processes. The integration of chemical synthesis into the development of CPPs made a significant contribution and even reached the clinical stage as a diagnostic tool. But constrained efforts still face serious problems in overcoming biobarriers to reach further achievements. In this work, we reviewed the roles of CPPs in anticancer drug delivery, focusing on their amino acid composition and sequences. As the most suitable point, we relied on significant changes in tumor volume in mice resulting from CPPs. We provide a review of individual CPPs and/or their derivatives in a separate subsection.

Enhanced anti-breast cancer efficacy of co-delivery liposomes of docetaxel and curcumin

The successful treatment of breast cancer is hampered by toxicity to normal cells, impaired drug accumulation at the tumor site, and multidrug resistance. We designed a novel multifunctional liposome, CUR-DTX-L, to co-deliver curcumin (CUR) and the chemotherapeutic drug docetaxel (DTX) for the treatment of breast cancer in order to address multidrug resistance (MDR) and the low efficacy of chemotherapy. The mean particle size, polydispersity index, zeta potential, and encapsulation efficiency of CUR-DTX-L were 208.53 ± 6.82 nm, 0.055 ± 0.001, -23.1 ± 2.1 mV, and 98.32 ± 2.37%, respectively. An in vitro release study and CCK-8 assays showed that CUR-DTX-L has better sustained release effects and antitumor efficacy than free drugs, the antitumor efficacy was verified by MCF-7 tumor-bearing mice, the CUR-DTX-L showed better antitumor efficacy than other groups, and the in vivo pharmacokinetic study indicated that the plasma concentration-time curve, mean residence time, and biological half-life time of CUR-DTX-L were significantly increased compared with free drugs, suggesting that it is a promising drug delivery system for the synergistic treatment of breast cancer.

Decapeptide Modified Doxorubicin Loaded Solid Lipid Nanoparticles as Targeted Drug Delivery System against Prostate Cancer

Growing instances of prostate cancer with poor prognosis have become a challenging task in cancer therapy. Luteinizing-hormone-releasing-hormone (LHRH) receptors are overexpressed in prostate cancer cells. Polyethylene glycol (PEG) conjugated lipids exhibit superiority in terms of retention/circulation in biological systems. PEGylated dipalmitoylphosphatedylethanolamine (DPPE-PEG), covalently linked with 6-hydrazinopyridine-3-carboxylic-acid, was conjugated with new LHRH-receptor positive peptide analog (DPPE-PEG-HYNIC-d-Glu-His-Trp-Ser-Tyr-d-Asn-Leu-d-Gln-Pro-Gly-NH₂). Surface modified doxorubicin (DOX) loaded solid lipid nanoparticle (SLN) was prepared using soylecithin, stearic acid and Poloxamer-188 by solvent emulsification/evaporation method for targeted delivery of DOX into prostate cancer cells. SLN, DOX loaded SLN (DSLN) and surface modified DSLN (M-DSLN) were characterized by means of their size, zeta potential, morphology, storage time, drug payload, and subsequent release kinetics studies. Homogeneity of surface morphology, upon modification of SLN, was revealed from the dynamic light scattering, atomic force microscopy, and scanning electron microscopic studies. Homogeneous adsolubilization of DOX throughout the hydrophobic moiety of SLN was established by the differential scanning calorimetric studies. Release of DOX were sustained in DSLN and M-DSLN. Cellular uptake and in vitro activities of formulations against LHRH positive PC3/SKBR3 cancer cell lines revealed higher cellular internalization, cytotoxicity that followed the sequence DOX < DSLN < M-DSLN. Dye staining and flow cytometry studies revealed higher apoptosis in cancer cells. Such receptor specific drug delivery systems are considered to have substantial potential in prostate cancer therapy.

Peptide-functionalized liposomes as therapeutic and diagnostic tools for cancer treatment

Clinically efficacious medication in anticancer therapy has been successfully designed with liposome-based nanomedicine. The liposomal formulation in cancer drug delivery can be facilitated with a functionalized peptide that mediates the specific drug delivery opportunities with increased drug penetrability, specific accumulation in the targeted site, and enhanced therapeutic efficacy. This review aims to focus on recent advances in peptide-functionalized liposomal formulation techniques in cancer diagnosis and treatment regarding recently published literature. It also will highlight different aspects of novel liposomal formulation techniques that incorporate surface functionalization with peptides for better anticancer effect and current challenges in peptide-functionalized liposomal drug formulation.

The dynamics and role of sphingolipids in eukaryotic organisms upon thermal adaptation

All living beings have an optimal temperature for growth and survival. With the advancement of global warming, the search for understanding adaptive processes to climate changes has gained prominence. In this context, all living beings monitor the external temperature and develop adaptive responses to thermal variations. These responses ultimately change the functioning of the cell and affect the most diverse structures and processes. One of the first structures to detect thermal variations is the plasma membrane, whose constitution allows triggering of intracellular signals that assist in the response to temperature stress. Although studies on this topic have been conducted, the underlying mechanisms of recognizing thermal changes and modifying cellular functioning to adapt to this condition are not fully understood. Recently, many reports have indicated the participation of sphingolipids (SLs), major components of the plasma membrane, in the regulation of the thermal stress response. SLs can structurally reinforce the membrane or/and send signals intracellularly to control numerous cellular processes, such as apoptosis, cytoskeleton polarization, cell cycle arresting and fungal virulence. In this review, we discuss how SLs synthesis changes during both heat and cold stresses, focusing on fungi, plants, animals and human cells. The role of lysophospholipids is also discussed.

Targeting Delivery of Platelets Inhibitor to Prevent Tumor Metastasis

Activated platelets have a high affinity for tumor cells, and consequently, they can protect tumor cells from environmental stress and immune attacks. Therefore, preventing platelet-tumor cell interaction can lead to the elimination of circulating tumor cells via natural killer cells and finally metastasis inhibition. It is also shown that CREKA (Cys-Arg-Glu-Lys-Ala), a tumor-homing pentapeptide, targets fibrin-fibronectin complexes that are found on the tumor stroma and the vessel walls. In this study, we linked CREKA to Ticagrelor, a reversible antagonist of the P2Y₁₂ receptor on platelets. In vitro experiments indicated that CREKA-Ticagrelor could not only inhibit the platelet-induced migration of tumor cells with an invasive phenotype but also prevent tumor-platelet interaction. In vivo antitumor and antimetastasis results of this drug showed that CREKA-Ticagrelor could specifically target the tumor tissues within 24 h post intravenous injection and suppress lung metastasis. Meanwhile, by having this antiplatelet drug targeted, its side effects were minimized, and bleeding risk was decreased. Thus, CREKA-Ticagrelor offers an efficient antimetastatic agent.

Decapeptide functionalized targeted mesoporous silica nanoparticles with doxorubicin exhibit enhanced apoptotic effect in breast and prostate cancer cells

BACKGROUND

Considering the increase in cancer cases and number of deaths per year worldwide, development of potential therapeutics is imperative. Mesoporous silica nanoparticles (MSNPs) are among the potential nanocarriers having unique properties for drug delivery. Doxorubicin (DOX), being the most commonly used drug, can be efficiently delivered to gonadotropin-releasing hormone (GnRH)-overexpressing cancer cells using functionalized MSNPs.

AIM

We report the development of decapeptide-conjugated MSNPs loaded with DOX for the targeted drug delivery in breast and prostate cancer cells.

MATERIALS AND METHODS

MSNPs were synthesized and subsequently functionalized with an analog of GnRH by using a heterobifunctional polyethylene glycol as a linker. These targeted MSNPs were then characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and Raman spectroscopy. An anticancer drug DOX was loaded and then characterized for drug loading. DOX-loaded nanocarriers were then studied for their cellular uptake using confocal microscopy. The cytotoxicity of DOX-loaded targeted MSNPs and DOX-loaded bare MSNPs was studied by performing MTT assay on MCF-7 (breast cancer) and LNCaP (prostate cancer) cells. Further, acridine orange/ethidium bromide staining, as well as flow cytometry, was performed to confirm the apoptotic mode of cancer cell death.

RESULTS

MSNPs were conjugated with polyethylene glycol as well as an agonist of GnRH and subsequently loaded with DOX. These targeted and bare MSNPs showed excellent porous structure and loading of DOX. Further, higher uptake of DOX-loaded targeted MSNPs was observed as compared to DOX-loaded bare MSNPs in GnRH-overexpressing breast (MCF-7) and prostate (LNCaP) cancer cells. The targeted MSNPs also showed significantly higher (P<0.001) cytotoxicity than DOX-loaded bare MSNPs at different time points. After 48 hours of treatment, the IC50 value for DOX-loaded targeted MSNPs was found to be 0.44 and 0.43 µM in MCF-7 and LNCaP cells, respectively. Acridine orange/ethidium bromide staining and flow cytometry analysis further confirmed the pathway of cell death through apoptosis.

CONCLUSION

This study suggests GnRH analog-conjugated targeted MSNPs can be the suitable and promising approach for targeted drug delivery in all hormone-dependent cancer cells.

pH-sensitive PEGylation of RIPL peptide-conjugated nanostructured lipid carriers: design and in vitro evaluation

BACKGROUND

RIPL peptide (IPLVVPLRRRRRRRRC)-conjugated nanostructured lipid carriers (RIPL-NLCs) can facilitate selective drug delivery to hepsin (Hpn)-expressing cancer cells, but they exhibit low stability in the blood. Generally, biocompatible and nontoxic poly(ethylene glycol) surface modification (PEGylation) can enhance NLC stability, although this may impair drug delivery and NLC clearance. To attain RIPL-NLC steric stabilization without impairing function, pH-sensitive cleavable PEG (cPEG) was grafted onto RIPL-NLCs (cPEG-RIPL-NLCs).

METHODS

Various types of NLC formulations including RIPL-NLCs, PEG-RIPL-NLCs, and cPEG-RIPL-NLCs were prepared using the solvent emulsification-evaporation method and characterized for particle size, zeta potential (ZP), and cytotoxicity. The steric stabilization effect was evaluated by plasma protein adsorption and phagocytosis inhibition studies. pH-sensitive cleavage was investigated using the dialysis method under different pH conditions. Employing a fluorescent probe (1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate [DiI]), in vitro drug delivery capacity of the cPEG-RIPL-NLCs under different pH conditions was also performed on Hpn-expressing SKOV3 cells and 3D-tumor spheroids.

RESULTS

All prepared NLCs showed homogenous dispersion (<220 nm in size) with a negative ZP (-18 to -22 mV), except for positively charged RIPL-NLCs (~10 mV), revealing no significant cytotoxicity in either SKOV3 or RAW 264.7 cell lines. cPEG-RIPL-NLC protein adsorption was 1.75-fold less than that of RIPL-NLCs, and PEGylation significantly reduced the macrophage uptake. PEG detachment from the cPEG-RIPL-NLCs was pH-sensitive and time dependent. At 2 hours incubation, cPEG-RIPL-NLCs and PEG-RIPL-NLCs exhibited comparable cellular uptake at pH 7.4, whereas cPEG-RIPL-NLC uptake was increased over 2-fold at pH 6.5. 3D-spheroid penetration also demonstrated pH-sensitivity: at pH 7.4, cPEG-RIPL-NLCs could not penetrate deep into the spheroid core region during 2 hours, whereas at pH 6.5, high fluorescence intensity in the core region was observed for both cPEG-RIPL-NLC-and RIPL-NLC-treated groups.

CONCLUSION

cPEG-RIPL-NLCs are good candidates for Hpn-selective drug targeting in conjunction with pH-responsive PEG cleavage.

Tumor-targeting delivery of herb-based drugs with cell-penetrating/tumor-targeting peptide-modified nanocarriers

Cancer has become one of the leading causes of mortality globally. The major challenges of conventional cancer therapy are the failure of most chemotherapeutic agents to accumulate selectively in tumor cells and their severe systemic side effects. In the past three decades, a number of drug delivery approaches have been discovered to overwhelm the obstacles. Among these, nanocarriers have gained much attention for their excellent and efficient drug delivery systems to improve specific tissue/organ/cell targeting. In order to enhance targeting efficiency further and reduce limitations of nanocarriers, nanoparticle surfaces are functionalized with different ligands. Several kinds of ligand-modified nanomedicines have been reported. Cell-penetrating peptides (CPPs) are promising ligands, attracting the attention of researchers due to their efficiency to transport bioactive molecules intracellularly. However, their lack of specificity and in vivo degradation led to the development of newer types of CPP. Currently, activable CPP and tumor-targeting peptide (TTP)-modified nanocarriers have shown dramatically superior cellular specific uptake, cytotoxicity, and tumor growth inhibition. In this review, we discuss recent advances in tumor-targeting strategies using CPPs and their limitations in tumor delivery systems. Special emphasis is given to activable CPPs and TTPs. Finally, we address the application of CPPs and/or TTPs in the delivery of plant-derived chemotherapeutic agents.

Effect of XlogP and Hansen Solubility Parameters on Small Molecule Modified Paclitaxel Anticancer Drug Conjugates Self-Assembled into Nanoparticles

Small molecule modified anticancer drug conjugates (SMMDCs) can self-assemble into nanoparticles (NPs) as therapeutic NP platforms for cancer treatment. Here we demonstrate that the XlogP and Hansen solubility parameters of paclitaxel (PTX) SMMDCs is essential for SMMDCs self-assembling into NPs. The amorphous state of PTX SMMDCs will also affect SMMDCs self-assembling into NPs. However, the antitumor activity of these PTX SMMDCs NPs decreased along with their XlogP values, indicating that a suitable XlogP value for designing the SMMDCs is important for self-assembling into NPs and for possessing antitumor activity. For higher level XlogP SMMDCs, a degradable linker should be considered in the design of SMMDCs to overcome the problem of lower antitumor activity. It is preferable that the hydrophilic groups in the SMMDCs should be present on the surface of self-assembling NPs.

Glioma and microenvironment dual targeted nanocarrier for improved antiglioblastoma efficacy

Drug delivery systems based on nanoparticles (nano-DDS) have aroused attentions for the treatment of glioblastoma (GBM), the most malignant brain cancer with a dismal prognosis. However, there are still numerous unmet challenges for traditional nano-DDS, such as the poor nanoparticle penetration, short retention in the GBM parenchyma and low glioma targeting ability. Herein, we used Pep-1 and CREKA peptides to construct a novel multifunctional GBM targeting nano-DDS (PC-NP). Pep-1 was used to overcome the blood-brain tumor barrier (BBTB) and home to glioma cells via interleukin-13 receptor-α2-mediated endocytosis, and CREKA was used to bind to fibrin-fibronectin complexes abundantly expressed in tumor microenvironment for enhanced retention in the GBM. Biological studies showed that the cellular uptake of PC-NP by U87MG cells was significantly enhanced compared with the non-targeting NP. Furthermore, CREKA modification increased the binding capacity of PC-NP to fibrin-fibronectin complexes as confirmed by the competition experiment. In accordance with the increased cellular uptake, PC-NP remarkably increased the cytotoxicity of its payload paclitaxel (PTX) against U87MG cells with an IC₅₀ of 0.176 μg/mL. In vivo fluorescence imaging and antiglioma efficacy evaluation further confirmed that PC-NP accumulated effectively and penetrated deeply into GBM tissue. PC-NP-PTX exhibited a median survival time as long as 61 days in intracranial GBM-bearing mice. In conclusion, our findings indicated PC-NP as a promising nano-DDS for GBM targeting delivery of anticancer drugs.

Science to Practice: Molecular-targeted Drug Delivery in Combination with Radiofrequency Ablation of Liver Cancer: A Magic Bullet?

In an effort to improve the technical success rates and clinical outcomes of radiofrequency (RF) ablation, Yan et al validated the use of a tumor-penetrating peptide and thermosensitive doxorubicin (DOX)-loaded nanoparticles in combination with RF ablation in a hepatocellular carcinoma mouse model. By achieving higher chemotherapeutic drug concentrations in target lesions, fewer toxic effects, and improved survival end points in an animal tumor model, the authors conclude that superior tumor treatment with RF ablation is possible when combined with molecular-targeted drug delivery systems.

Targeting Strategies for the Combination Treatment of Cancer Using Drug Delivery Systems

Cancer cells have characteristics of acquired and intrinsic resistances to chemotherapy treatment-due to the hostile tumor microenvironment-that create a significant challenge for effective therapeutic regimens. Multidrug resistance, collateral toxicity to normal cells, and detrimental systemic side effects present significant obstacles, necessitating alternative and safer treatment strategies. Traditional administration of chemotherapeutics has demonstrated minimal success due to the non-specificity of action, uptake and rapid clearance by the immune system, and subsequent metabolic alteration and poor tumor penetration. Nanomedicine can provide a more effective approach to targeting cancer by focusing on the vascular, tissue, and cellular characteristics that are unique to solid tumors. Targeted methods of treatment using nanoparticles can decrease the likelihood of resistant clonal populations of cancerous cells. Dual encapsulation of chemotherapeutic drug allows simultaneous targeting of more than one characteristic of the tumor. Several first-generation, non-targeted nanomedicines have received clinical approval starting with Doxil® in 1995. However, more than two decades later, second-generation or targeted nanomedicines have yet to be approved for treatment despite promising results in pre-clinical studies. This review highlights recent studies using targeted nanoparticles for cancer treatment focusing on approaches that target either the tumor vasculature (referred to as 'vascular targeting'), the tumor microenvironment ('tissue targeting') or the individual cancer cells ('cellular targeting'). Recent studies combining these different targeting methods are also discussed in this review. Finally, this review summarizes some of the reasons for the lack of clinical success in the field of targeted nanomedicines.

High yield, scalable and remotely drug-loaded neutrophil-derived extracellular vesicles (EVs) for anti-inflammation therapy

Extracellular vesicles (EVs) are nanoscale membrane-formed compartments naturally secreted from cells, which are intercellular mediators regulating physiology and pathogenesis, therefore they could be a novel therapeutic carrier for targeted delivery. However, the translation of EVs is hindered by the heterogeneous composition, low yield, inefficient drug loading and unlikely scalability. Here we report a strategy to generate EVs using nitrogen cavitation (NC-EVs) that instantly disrupts neutrophils to form nanosized membrane vesicles. NC-EVs are similar to naturally secreted EVs (NS-EVs), but contain less subcellular organelles and nuclear acids. The production of NC-EVs was increased by 16 folds and is easy to scale up for clinical use compared to NS-EVs. To examine the usefulness of NC-EVs as a drug delivery platform, piceatannol (an anti-inflammation drug) was remotely loaded in NC-EVs via the pH gradient. We found that piceatannol-loaded NC-EVs dramatically alleviated acute lung inflammation/injury and sepsis induced by lipopolysaccharide (LPS). Our studies reveal that nitrogen cavitation is a novel approach to efficiently generate EVs from any cell type and could be exploited for personalized nanomedicine.

Rituximab-conjugated, doxorubicin-loaded microbubbles as a theranostic modality in B-cell lymphoma

This study evaluated rituximab-conjugated, doxorubicin-loaded microbubbles (RDMs) in combination with ultrasound as molecular imaging agents for early diagnosis of B cell lymphomas, and as a targeted drug delivery system. Rituximab, a monoclonal CD20 antibody, was attached to the surfaces of doxorubicin-loaded microbubbles. RDM binding to B cell lymphoma cells was assessed using immunofluorescence. The cytotoxic effects of RDMs in combination with ultrasound (RDMs+US) were evaluated in vitro in CD20+ and CD20– cell lines, and its antitumor activities were assessed in Raji (CD20+) and Jurkat (CD20–) lymphoma cell-grafted mice. RDMs specifically bound to CD20+ cells in vitro and in vivo. Contrast enhancement was monitored in vivo via ultrasound. RDM peak intensities and contrast enhancement durations were higher in Raji than in Jurkat cell-grafted mice (P<0.05). RDMs+US treatment resulted in improved antitumor effects and reduced systemic toxicity in Raji cell-grafted mice compared with other treatments (P<0.05). Our results showed that RDMs+US enhanced tumor targeting, reduced systemic toxicity, and inhibited CD20+ B cell lymphoma growth in vivo. Targeted RDMs could be employed as ultrasound molecular imaging agents for early diagnosis, and are an effective targeted drug delivery system in combination with ultrasound for CD20+ B cell malignancy treatment.

State of the Art of Stimuli-Responsive Liposomes for Cancer Therapy

Specific delivery of therapeutic agents to solid tumors and their bioavailability at the target site are the most clinically important and challenging goals in cancer therapy. Liposomes are promising nanocarriers and have been well investigated for cancer therapy. In spite of preferred accumulation in tumors via the enhanced permeability and retention (EPR) effect, inefficient drug release at the target site and endosomal entrapment of long circulating liposomes are very important obstacles for achieving maximum anticancer efficacy. Thus, additional strategies such as stimulus-sensitive drug release are necessary to improve efficacy. Stimuli-sensitive liposomes are stable in blood circulation, however, activated by responding to external or internal stimuli and control the cargo release at the target site. This review focuses on state of the art of stimuli-responsive liposomes. Both external stimuli-responsive liposomes, including hyperthermia (HT), magnetic, light, and ultrasound-sensitive liposomes and internal stimuli (pH, reduction, and enzyme) responsive liposomes are covered.

A54 Peptide Modified and Redox-Responsive Glucolipid Conjugate Micelles for Intracellular Delivery of Doxorubicin in Hepatocarcinoma Therapy

Redox-responsive nanomaterials applied in drug delivery systems (DDS) have attracted an increasing attention in pharmaceutical research as a carrier for antitumor therapy. However, there would be unwanted drug release from a redox-responsive DDS with no selection at nontarget sites, leading to undesirable toxicities in normal tissues and cells. Here, an A54 peptide modified and PEGylated reduction cleavable glucolipid conjugate (A54-PEG-CSO-ss-SA, abbreviated to APC_ssA) was designed for intracellular delivery of doxorubicin (DOX). The synthesized APC_ssA could be assembled via micellization self-assembly in aqueous water above the critical micelle concentration (54.9 μg/mL) and exhibited a high drug encapsulation efficiency (77.92%). The APC_ssA micelles showed an enhanced redox sensitivity in that the disulfide bond could be degraded quickly and the drug would be released from micelles in 10 mM levels of glutathione (GSH). The cellular uptake studies highlighted the affinity of APC_ssA micelles toward the hepatoma cells (BEL-7402) compared to that toward HepG2 cells. In contrast with the nonresponsive conjugate, the drug was released from APC_ssA micelles more quickly in 10 mM level of GSH concentration (tumor cells). Moreover, the DOX-loaded APC_ssA micelles displayed an increased cytotoxicity which was 1.6- to 2.0-fold that of unmodified and nonresponsive micelles. In vivo, the APC_ssA micelles had stronger distribution to liver and hepatoma tissue and prolonged the circulation and retention time, while the drug release only occurred in the tumor tissue. The APC_ssA/DOX showed the tumor inhibition rate equal to that of commercial doxorubicin hydrochloric without negative consequence. This study suggested that the APC_ssA/DOX showed promising potential to treat the tumor for its special tumor targeting, selective intracellular drug release, enhanced antitumor activity, and reduced toxicity on normal tissues.

Recent insights in nanotechnology-based drugs and formulations designed for effective anti-cancer therapy

The rapid development of nanotechnology provides alternative approaches to overcome several limitations of conventional anti-cancer therapy. Drug targeting using functionalized nanoparticles to advance their transport to the dedicated site, became a new standard in novel anti-cancer methods. In effect, the employment of nanoparticles during design of antineoplastic drugs helps to improve pharmacokinetic properties, with subsequent development of high specific, non-toxic and biocompatible anti-cancer agents. However, the physicochemical and biological diversity of nanomaterials and a broad spectrum of unique features influencing their biological action requires continuous research to assess their activity. Among numerous nanosystems designed to eradicate cancer cells, only a limited number of them entered the clinical trials. It is anticipated that progress in development of nanotechnology-based anti-cancer materials will provide modern, individualized anti-cancer therapies assuring decrease in morbidity and mortality from cancer diseases. In this review we discussed the implication of nanomaterials in design of new drugs for effective antineoplastic therapy and describe a variety of mechanisms and challenges for selective tumor targeting. We emphasized the recent advantages in the field of nanotechnology-based strategies to fight cancer and discussed their part in effective anti-cancer therapy and successful drug delivery.