Nanomedicine therapeutic approaches to overcome cancer drug resistance

Self-assembling peptide-etoposide nanofibers for overcoming multidrug resistance

We developed a new strategy to overcome the MDR of etoposide using self-assembling nanofibers. Compared with the original etoposide, the inhibitory activity of Nap-GFFpYK-etoposide1/2 against murine Lewis lung cancer or breast cancer cells was increased 10 times, and 20 times on these cells with artificially overexpressed MDR1. Our method to synthesize and separate etoposide isomers provides a new strategy for the modification of this drug.

Selenium-doped calcium phosphate biomineral reverses multidrug resistance to enhance bone tumor chemotherapy

The construction of a functional drug delivery system to reverse the multidrug resistance (MDR) of bone tumors in cases of failed chemotherapy remains a challenge. Herein, we demonstrate a selenium-doped calcium phosphate (Se-CaP) biomineral with high biocompatibility, biodegradability and pH-sensitive drug release properties. Se-CaP may not only serve as an effective drug-carrier to enhance the uptake of doxorubicin (DOX), but may also synchronously induce caspases-mediated apoptosis of osteosarcoma by generating intracellular reactive oxygen species (ROS). Furthermore, in vitro and in vivo studies obviously demonstrate that Se-CaP can reverse the MDR of osteosarcoma by down-regulating the expression of MDR-related ABC (ATP binding cassette) transporters proteins (ABCB1 and ABCC1). Finally, DOX-loaded Se-CaP can significantly inhibit DOX-resistant MG63 (MG63/DXR) tumor growth in nude mice. Considering its biomimetic chemical properties, the Se-CaP biomineral, with the multiple functions mentioned above, could be a promising candidate for treating bone tumors with MDR characteristics.

Lipoproteins-Nanocarriers as a Promising Approach for Targeting Liver Cancer: Present Status and Application Prospects

The prevalence of liver cancer is increasing over the years and it is the fifth leading cause of mortality worldwide. The intrusive features and burden of low survival rate make it a global health issue in both developing and developed countries. The recommended chemotherapy drugs for patients in the intermediate and advanced stages of various liver cancers yield a low response rate due to the nonspecific nature of drug delivery, thus warranting the search for new therapeutic strategies and potential drug delivery carriers. There are several new drug delivery methods available to ferry the targeted molecules to the specific biological environment. In recent years, the nano assembly of lipoprotein moieties (lipidic nanoparticles) has emerged as a promising and efficiently tailored drug delivery system in liver cancer treatment. This increased precision of nano lipoproteins conjugates in chemotherapeutic targeting offers new avenues for the treatment of liver cancer with high specificity and efficiency. This present review is focused on concisely outlining the knowledge of liver cancer diagnosis, existing treatment strategies, lipoproteins, their preparation, mechanism and their potential application in the treatment of liver cancer.

Maximizing the potency of oxaliplatin coated nanoparticles with folic acid for modulating tumor progression in colorectal cancer

One of the challenges of nanotechnology is to improve the efficacy of treatments for diseases, in order to reduce morbidity and mortality rates. Following this line of study, we made a nanoparticle formulation with a small size, uniform surfaces, and a satisfactory encapsulation coefficient as a target for colorectal cancer cells. The results of binding and uptake prove that using the target system with folic acid works: Using this system, cytotoxicity and cell death are increased when compared to using free oxaliplatin. The data show that the system maximized the efficiency of oxaliplatin in modulating tumor progression, increasing apoptosis and decreasing resistance to the drug. Thus, for the first time, our findings suggest that PLGA-PEG-FA increases the antitumor effectiveness of oxaliplatin by functioning as a facilitator of drug delivery in colorectal cancer.

Combined pH-responsive chemotherapy and glutathione-triggered photosensitization to overcome drug-resistant hepatocellular carcinoma — a SPP/JPP Young Investigator Award paper

Doxorubicin (DOX) resistance, which results in a reduced accumulation of DOX in the nucleus and hence decreased DNA damage, is a major challenge for chemotherapy against hepatocellular carcinoma. In this paper, we combined chemotherapy with photodynamic therapy (PDT) to combat DOX-resistant human hepatocellular carcinoma cells. We have prepared the polymeric micelles conjugating with DOX and zinc(II) phthalocyanine (ZnPc) through a pH-responsive hydrazone linker and a glutathione (GSH)-responsive disulfide linker, respectively. The polymeric micelles (DOX-ZnPc-micelles) exhibited a spherical shape with a size of about 98 nm diameter and showed excellent stability in aqueous solution. Due to the self-quenching of the ZnPc inside the micelles, DOX-ZnPc-micelles did not emit fluorescence upon red light irradiation. Drug release experiments verified that DOX and ZnPc could be released under acidic conditions and reducing environments, respectively. A higher concentration of DOX was internalized into DOX-resistant R-HepG2 cells through the delivery of polymeric micelles when compared with the free DOX, hence DOX-ZnPc-micelles exhibited a significant enhancement in anticancer activity. The IC[Formula: see text] value of DOX against R-HepG2 cells was found to be 21 [Formula: see text]M when combined with PDT and it was 5-fold less than that of a single treatment of DOX (102 [Formula: see text]M). The DOX-ZnPc-micelles could induce cell apoptosis and necrosis on R-HepG2 cells by combined therapeutic modalities, while these micelles induced only apoptosis on HepG2 cells. We have demonstrated that utilization of polymeric micelles can significantly enhance the cellular uptake and cytotoxicity of DOX against R-HepG2 cells when compared with free DOX. Moreover, PDT can act as an adjuvant therapeutic modality and combine with chemotherapy to further improve therapeutic efficacy. Overall speaking, DOX-ZnPc-micelles can overcome DOX resistance and induce a synergistic therapeutic effect against DOX-resistant R-HepG2 cells, hence improving the therapeutic efficacy when compared with monotherapy.

Targeted delivery of 5-fluorouracil-1-acetic acid (5-FA) to cancer cells overexpressing epithelial growth factor receptor (EGFR) using virus-like nanoparticles

Chemotherapy is widely used in cancer treatments. However, non-specific distribution of chemotherapeutic agents to healthy tissues and normal cells in the human body always leads to adverse side effects and disappointing therapeutic outcomes. Therefore, the main aim of this study was to develop a targeted drug delivery system based on the hepatitis B virus-like nanoparticle (VLNP) for specific delivery of 5-fluorouracil-1-acetic acid (5-FA) to cancer cells expressing epithelial growth factor receptor (EGFR). 5-FA was synthesized from 5-fluorouracil (5-FU), and it was found to be less toxic than the latter in cancer cells expressing different levels of EGFR. The cytotoxicity of 5-FA increased significantly after being conjugated on the VLNP. A cell penetrating peptide (CPP) of EGFR was displayed on the VLNP via the nanoglue concept, for targeted delivery of 5-FA to A431, HT29 and HeLa cells. The results showed that the VLNP displaying the CPP and harboring 5-FA internalized the cancer cells and killed them in an EGFR-dependent manner. This study demonstrated that the VLNP can be used to deliver chemically modified 5-FU derivatives to cancer cells overexpressing EGFR, expanding the applications of the VLNP in targeted delivery of chemotherapeutic agents to cancer cells overexpressing this transmembrane receptor.

Drug Delivery Systems of Natural Products in Oncology

In recent decades, increasing interest in the use of natural products in anticancer therapy field has been observed, mainly due to unsolved drug-resistance problems. The antitumoral effect of natural compounds involving different signaling pathways and cellular mechanisms has been largely demonstrated in in vitro and in vivo studies. The encapsulation of natural products into different delivery systems may lead to a significant enhancement of their anticancer efficacy by increasing in vivo stability and bioavailability, reducing side adverse effects and improving target-specific activity. This review will focus on research studies related to nanostructured systems containing natural compounds for new drug delivery tools in anticancer therapies.

Reducing Doxorubicin resistance in breast cancer by liposomal FOXM1 aptamer: In vitro and in vivo

AIMS

Drug resistance is one of the main obstacles in cancer chemotherapy. The forkhead box M1 (FOXM1) is a transcription factor and its overexpression in breast cancer is related to resistance to chemotherapy. In this study, we prepare liposomal FOXM1 aptamer (Lip-FOXM1apt) and evaluate its effects on Doxorubicin (Dox) resistance in vitro and in vivo.

MAIN METHODS

MTT assay, cell association, cellular uptake, Annexin V-FITC/PI dual staining assay were investigated in MDA-MB-231, MCF-7, 4T1. In vivo studies were performed in 4T1 tumor-bearing BALB/c mice.

KEY FINDINGS

We found that the combination therapy of Dox and Lip-FOXM1apt significantly increases both Dox cytotoxicity on cancer cells as well as Dox-induced apoptosis. Administering Lip-FOXM1apt remarkably improved the anti-tumor efficacy of Dox in mice model that was strikingly more effective than Dox monotherapy.

SIGNIFICANCE

Taken together, this study provides a new strategy to overcome Dox resistance and merits further investigation.

Co-delivery of a RanGTP inhibitory peptide and doxorubicin using dual-loaded liposomal carriers to combat chemotherapeutic resistance in breast cancer cells

BACKGROUND

Multidrug resistance (MDR) limits the beneficial outcomes of conventional breast cancer chemotherapy. Ras-related nuclear protein (Ran-GTP) plays a key role in these resistance mechanisms, assisting cancer cells to repair damage to DNA. Herein, we investigate the co-delivery of Ran-RCC1 inhibitory peptide (RAN-IP) and doxorubicin (DOX) to breast cancer cells using liposomal nanocarriers.

RESEARCH DESIGN

A liposomal delivery system, co-encapsulating DOX, and RAN-IP, was prepared using a thin-film rehydration technique. Dual-loaded liposomes were optimized by systematic modification of formulation variables. Real-Time-Polymerase Chain Reaction was used to determine Ran-GTP mRNA expression. In vitro cell lines were used to evaluate the effect of loaded liposomes on the viability of breast and lung cancer cell lines. In vivo testing was performed on a murine Solid Ehrlich Carcinoma model.

RESULTS

RAN-IP reversed the Ran-expression-mediated MDR by inhibiting the Ran DNA damage repair function. Co-administration of RAN-IP enhanced sensitivity of DOX in breast cancer cell lines. Finally, liposome-mediated co-delivery with RAN-IP improved the anti-tumor effect of DOX in tumor-bearing mice when compared to single therapy.

CONCLUSIONS

This study is the first to show the simultaneous delivery of RAN-IP and DOX using liposomes can be synergistic with DOX and lead to tumor regression in vitro and in vivo.

LINC00470 promotes tumour proliferation and invasion, and attenuates chemosensitivity through the LINC00470/miR-134/Myc/ABCC1 axis in glioma

Glioma is the most common primary malignant tumour in the brain; temozolomide (TMZ) is the most prevalent chemotherapeutic drug currently used to combat this cancer. We reported previously that the long intergenic non‐protein coding RNA 470 (LINC00470) is a novel prognostic biomarker for glioma and promotes the tumour growth in an intracranial transplantation mouse model. However, the effects of LINC00470 on glioma cell proliferation, invasion and TMZ chemosensitivity, as well as its molecular mechanism, remain unclear. In this study, we found elevated expression levels of LINC00470 and MYC in glioma tissues and cells and decreased expression of microRNA‐134 (miR‐134). Functional studies have shown that LINC00470 promotes proliferation and invasion, and attenuates chemosensitivity of glioma cells, while miR‐134 exerts the opposite effect. In the rescue experiments, the tumorigenic effect of LINC00470 was offset by miR‐134. In the mechanism study, we found that LINC00470 was a competitive endogenous RNA (ceRNA) of miR‐134 and that miR‐134 can directly target MYC and negatively regulate its expression. Furthermore, MYC was positively correlated with ATP‐binding cassette subfamily C member 1 (ABCC1) expression in glioma cells and MYC up‐regulated ABCC1 expression. Further studies found that LINC00470 regulated MYC by sponging miR‐134 to regulate the expression of ABCC1. We concluded that LINC00470 promoted the expression of MYC and ABCC1 by suppressing miR‐134, thus promoting glioma cell proliferation and invasion, and attenuating TMZ chemosensitivity. Moreover, the LINC00470/miR‐134/MYC/ABCC1 axis constitutes a potential therapeutic target.

Development of Novel Heparin/Protamine Nanoparticles Useful for Delivery of Exogenous Proteins In Vitro and In Vivo

We previously reported that heparin/protamine particles (LHPPs) produced as nanoparticles through simple mixing of raw materials exhibit sustained protein release and can be retained in cells. In the present study, we modified LHPPs without employing any organic synthetic approach. The resulting LHPPs were re-named as improved LHPPs (i-LHPPs) and have the ability to retain cell-penetrating peptides (GRKKRRQRRRPPQ) based on electrostatic interactions. We examined whether i-LHPPs can introduce exogenous proteins (i.e., lacZ protein encoding bacterial β-galactosidase) into cultured cells in vitro, or into murine hepatocytes in vivo through intravenous injection to anesthetized mice. We found an accumulation of the transferred protein in both in vitro cultured cells and in vivo hepatocytes. To the best of our knowledge, reports of successful in vivo delivery to hepatocytes are rare. The i-LHPP-based protein delivery technique will be useful for in vivo functional genetic modification of mouse hepatocytes using Cas9 protein-mediated genome editing targeting specific genes, leading to the creation of hepatic disease animal models for research that aims to treat liver diseases.

Past, Present, and Future of Anticancer Nanomedicine

This review aims to summarize the methods that have been used till today, highlight methods that are currently being developed, and predict the future roadmap for anticancer therapy. In the beginning of this review, established approaches for anticancer therapy, such as conventional chemotherapy, hormonal therapy, monoclonal antibodies, and tyrosine kinase inhibitors are summarized. To counteract the side effects of conventional chemotherapy and to increase limited anticancer efficacy, nanodrug- and stem cell-based therapies have been introduced. However, current level of understanding and strategies of nanodrug and stem cell-based therapies have limitations that make them inadequate for clinical application. Subsequently, this manuscript reviews methods with fewer side effects compared to those of the methods mentioned above which are currently being investigated and are already being applied in the clinic. The newer strategies that are already being clinically applied include cancer immunotherapy, especially T cell-mediated therapy and immune checkpoint inhibitors, and strategies that are gaining attention include the manipulation of the tumor microenvironment or the activation of dendritic cells. Tumor-associated macrophage repolarization is another potential strategy for cancer immunotherapy, a method which activates macrophages to immunologically attack malignant cells. At the end of this review, we discuss combination therapies, which are the future of cancer treatment. Nanoparticle-based anticancer immunotherapies seem to be effective, in that they effectively use nanodrugs to elicit a greater immune response. The combination of these therapies with others, such as photothermal or tumor vaccine therapy, can result in a greater anticancer effect. Thus, the future of anticancer therapy aims to increase the effectiveness of therapy using various therapies in a synergistic combination rather than individually.

Cancer stem cells and nanomedicine: new opportunities to combat multidrug resistance?

'Multidrug resistance' (MDR) is a difficult challenge for cancer treatment. The combined role of cytochrome P450 enzymes (CYPs) and active efflux transporters (AETs) in cancer cells appears relevant in inducing MDR. Chemotherapeutic drugs can be substrates of both CYPs and AETs and CYP inducers or inhibitors can produce the same effects on AETs. In addition, a small subpopulation of cancer stem-like cells (CSCs) appears to survive conventional chemotherapy, leading to recurrent disease. Natural products appear efficacious against CSCs; their combinational treatments with standard chemotherapy are promising for cancer eradication, in particular when supported by nanotechnologies.

Near-infrared photoresponsive drug delivery nanosystems for cancer photo-chemotherapy

Drug delivery systems (DDSs) based on nanomaterials have shown a promise for cancer chemotherapy; however, it remains a great challenge to localize on-demand release of anticancer drugs in tumor tissues to improve therapeutic effects and minimize the side effects. In this regard, photoresponsive DDSs that employ light as an external stimulus can offer a precise spatiotemporal control of drug release at desired sites of interest. Most photoresponsive DDSs are only responsive to ultraviolet-visible light that shows phototoxicity and/or shallow tissue penetration depth, and thereby their applications are greatly restricted. To address these issues, near-infrared (NIR) photoresponsive DDSs have been developed. In this review, the development of NIR photoresponsive DDSs in last several years for cancer photo-chemotherapy are summarized. They can achieve on-demand release of drugs into tumors of living animals through photothermal, photodynamic, and photoconversion mechanisms, affording obviously amplified therapeutic effects in synergy with phototherapy. Finally, the existing challenges and further perspectives on the development of NIR photoresponsive DDSs and their clinical translation are discussed.

Curcumin Nanoparticles and Their Cytotoxicity in Docetaxel-Resistant Castration-Resistant Prostate Cancer Cells

Most prostate cancer patients develop resistance to anti-androgen therapy. This is referred to as castration-resistant prostate cancer (CRPC). Docetaxel (DTX) is the mainstay treatment against CRPC. However, over time patients eventually develop DTX resistance, which is the cause of the cancer-related mortality. Curcumin (CUR) as a natural compound has been shown to have very broad pharmacological activities, e.g., anti-inflammatory and antioxidant properties. However, CUR is very hydrophobic. The objective of this study was to develop CUR nanoparticles (NPs) and evaluate their cytotoxicity in DTX-resistant CRPC cells for the treatment of DTX-resistant CRPC. We tested solubility of CUR in different lipids and surfactants. Finally, Miglyol 812 and D-alpha-tocopheryl poly (ethylene glycol) succinate 1000 (TPGS) were chosen to prepare lipid-based NPs for CUR. We fully characterized CUR NPs that had particle size < 150 nm, high drug loading (7.5%), and entrapment efficiency (90%). Moreover, the CUR NPs were successfully lyophilized without using cryoprotectants. We tested the cytotoxicity of blank NPs, free CUR, and CUR NPs in sensitive DU145 and PC3 cells as well as their matching docetaxel-resistant cells. Cytotoxicity studies showed that blank NPs were very safe for all tested prostate cancer cell lines. Free CUR overcame the resistance in PC3 cells, but not in DU145 cells. In contrast, CUR NPs significantly increased CUR potency in all tested cell lines. Importantly, CUR NPs completely restored CUR potency in both resistant DU145 and PC3 cells. These results demonstrate that the CUR NPs have potential to overcome DTX resistance in CRPC.

ROS-Mediated Therapeutic Strategy in Chemo-/Radiotherapy of Head and Neck Cancer

Head and neck cancer is a highly genetic and metabolic heterogeneous collection of malignancies of the lip, oral cavity, salivary glands, pharynx, esophagus, paranasal sinuses, and larynx with five-year survival rates ranging from 12% to 93%. Patients with head and neck cancer typically present with advanced stage III, IVa, or IVb disease and are treated with comprehensive modality including chemotherapy, radiotherapy, and surgery. Despite advancements in treatment modality and technique, noisome recurrence, invasiveness, and resistance as well as posttreatment complications severely influence survival rate and quality of life. Thus, new therapeutic strategies are urgently needed that offer enhanced efficacy with less toxicity. ROS in cancer cells plays a vital role in regulating cell death, DNA repair, stemness maintenance, metabolic reprogramming, and tumor microenvironment, all of which have been implicated in resistance to chemo-/radiotherapy of head and neck cancer. Adjusting ROS generation and elimination to reverse the resistance of cancer cells without impairing normal cells show great hope in improving the therapeutic efficacy of chemo-/radiotherapy of head and neck cancer. In the current review, we discuss the pivotal and targetable redox-regulating system including superoxide dismutases (SODs), tripeptide glutathione (GSH), thioredoxin (Trxs), peroxiredoxins (PRXs), nuclear factor erythroid 2-related factor 2/Kelch-like ECH-associated protein 1 (Nrf2/keap1), and mitochondria electron transporter chain (ETC) complexes and their roles in regulating ROS levels and their clinical significance implicated in chemo-/radiotherapy of head and neck cancer. We also summarize several old drugs (referred to as the non-anti-cancer drugs used in other diseases for a long time) and small molecular compounds as well as natural herbs which effectively modulate cellular ROS of head and neck cancer to synergize the efficacy of conventional chemo-/radiotherapy. Emerging interdisciplinary techniques including photodynamic, nanoparticle system, and Bio-Electro-Magnetic-Energy-Regulation (BEMER) therapy are promising measures to broaden the potency of ROS modulation for the benefit of chemo-/radiotherapy in head and neck cancer.

Tetrandrine: a review of its anticancer potentials, clinical settings, pharmacokinetics and drug delivery systems

OBJECTIVES

Tetrandrine, a natural bisbenzylisoquinoline alkaloid, possesses promising anticancer activities on diverse tumours. This review provides systematically organized information on cancers of tetrandrine in vivo and in vitro, discuss the related molecular mechanisms and put forward some new insights for the future investigations.

KEY FINDINGS

Anticancer activities of tetrandrine have been reported comprehensively, including lung cancer, colon cancer, bladder cancer, prostate cancer, ovarian cancer, gastric cancer, breast cancer, pancreatic cancer, cervical cancer and liver cancer. The potential molecular mechanisms corresponding to the anticancer activities of tetrandrine might be related to induce cancer cell apoptosis, autophagy and cell cycle arrest, inhibit cell proliferation, migration and invasion, ameliorate metastasis and suppress tumour cell growth. Pharmaceutical applications of tetrandrine combined with nanoparticle delivery system including liposomes, microspheres and nanoparticles with better therapeutic efficiency have been designed and applied encapsulate tetrandrine to enhance its stability and efficacy in cancer treatment.

SUMMARY

Tetrandrine was proven to have definite antitumour activities. However, the safety, bioavailability and pharmacokinetic parameter studies on tetrandrine are very limited in animal models, especially in clinical settings. Our present review on anticancer potentials of tetrandrine would be necessary and highly beneficial for providing guidelines and directions for further research of tetrandrine.

3D culture technologies of cancer stem cells: promising ex vivo tumor models

Cancer stem cells have been shown to be important in tumorigenesis processes, such as tumor growth, metastasis, and recurrence. As such, many three-dimensional models have been developed to establish an ex vivo microenvironment that cancer stem cells experience under in vivo conditions. Cancer stem cells propagating in three-dimensional culture systems show physiologically related signaling pathway profiles, gene expression, cell-matrix and cell-cell interactions, and drug resistance that reflect at least some of the tumor properties seen in vivo. Herein, we discussed the presently available Cancer stem cell three-dimensional culture models that use biomaterials and engineering tools and the biological implications of these models compared to the conventional ones.

A phase I dose-escalation and pharmacokinetic study of a micellar nanoparticle with entrapped docetaxel (CPC634) in patients with advanced solid tumours

BACKGROUND

CPC634 is docetaxel entrapped in core-cross linked polymeric micelles. In preclinical studies, CPC634 demonstrated enhanced pharmacokinetics and improved therapeutic index. This phase I dose escalation study is the first-in-human study with CPC634.

METHODS

adult patients with advanced solid tumours received CPC634 intravenously either 3-weekly (Q3W) (part 1, dose range 15-100 mg/m²), 2-weekly (Q2W) (part 2, 45 mg/m²) or Q3W with dexamethasone premedication (part 3, 60 mg/m²).

RESULTS

thirty-three patients were enrolled. Skin toxicity was dose limiting (DLT) at ≥60 mg/m² in part 1 and at 45 mg/m² in part 2 and was the most common CPC634 related grade ≥ 3 adverse event (24%). With dexamethasone premedication no DLTs were observed at 60 mg/m² Q3W. CPC634 exhibited a dose-proportional pharmacokinetic profile. At 60 mg/m², the plasma area under the curve was 4067.5 ± 2974.0 ng/h/mL and the peak plasma level 217.3 ± 91.9 ng/mL with a half-life of 39.7 ± 9.4 h for released docetaxel.

CONCLUSION

CPC634 could be administered safely upon pretreatment with dexamethasone. Cumulative skin toxicity was the main DLT. The recommended phase 2 dose was determined at 60 mg/m² Q3W with dexamethasone premedication.

The Pattern of Residual Tumor After Neoadjuvant Chemotherapy for Locally Advanced Esophageal Cancer and Its Clinical Significance

OBJECTIVES

To investigate the residual pattern of esophageal cancer in the esophageal wall after neoadjuvant chemotherapy (NAC) and its clinical significance.

BACKGROUND

NAC is a standard treatment for locally advanced esophageal cancer; however, residual tumor patterns in resected specimens after NAC and their clinico-pathological characteristics remain unknown.

METHODS

One hundred twenty consecutive patients with cT3 or deeper esophageal cancer underwent curative esophagectomy after NAC and achieved grade 2 histological responses between 2000 and 2016. Hematoxylin-eosin staining of residual tumor sections revealed 4 remnant categories: Type 1: shallow, Type 2: central, Type 3: deep, and Type 4: diffuse. We examined associations between these Types and clinico-pathological factors, including prognosis.

RESULTS

Forty-five (38%) specimens had no residual tumor cells in the mucosal layer. The adventitia layer displayed the lowest residual tumor cell frequency (18%) among all layers. Types 1, 2, 3, and 4 residual tumor patterns were found in 49 (41%), 33 (28%), 9 (8%), and 29 (24%) patients, respectively. Type 4 showed the maximum standard uptake value after NAC; Types 3 and 4 had higher ratios of venous invasion than Type 1 or 2. Patients with Type 3 or 4 more frequently developed pleural dissemination or distant metastasis than patients with Type 1 or 2. Survival was similar among the 4 Types.

CONCLUSIONS

After NAC for locally advanced esophageal cancer, the shallow residual tumor pattern was most common, but approximately 40% of specimens showed no tumor cells in the mucosal layer. Deep and diffuse remnant patterns were associated with high risks of pleural dissemination and distant metastasis.

Temozolomide, Gemcitabine, and Decitabine Hybrid Nanoconjugates: From Design to Proof-of-Concept (PoC) of Synergies toward the Understanding of Drug Impact on Human Glioblastoma Cells

This paper emphasizes the synthesis of novel hybrid drug nanoparticles (Hyb-D-AuNPs) based on gold-temozolomide (TMZ) complexes combined with gemcitabine (GEM) and decitabine (DAC) to improve the efficiency and reduce the resistance of U87 malignant glial cells against TMZ. All products were evaluated by several spectroscopic techniques (Raman, UV-Vis) and transmission electron microscopy (TEM). Besides, for therapeutic purposes, the effect of these nanoparticles on cell proliferation and toxicity was evaluated, which clearly showed a synergic action of TMZ and GEM. Through the analysis of the exometabolome by nuclear magnetic resonance (NMR), the metabolic changes in the culture medium were measured in glial cells. Moreover, these nanoparticles are especially appropriated to the thermal destruction of cancer in the case of photothermal therapy due to their photothermal heating properties. This study presents an original chemical approach that it could play a central role in the field of nanomedicine, with novel perspectives for the development of new drugs and active targeting in glioblastoma multiforme (GBM) cancer therapy.

Gas-blasting nanocapsules to accelerate carboplatin lysosome release and nucleus delivery for prostate cancer treatment

To improve therapeutic effect and reduce severely side effects of carboplatin (CBP), the gas-generating nanocapsules were developed to accelerate CBP lysosome release and nucleus delivery. CBP/SB-NC was prepared by co-loading CBP and NaHCO₃ (SB) in nanocapsules using w/o/w emulsification solvent evaporation. They exhibited vesicle-like spherical morphology, uniform particle size and negative zeta potential. Reaching the tumor site with a relatively high concentration is the first step for CBP delivery and the results showed that CBP/SB-NC could effectively increase drug accumulation at tumor site. After that, the drug delivery carriers need to be internalized into tumor cells and the in vitro cellular uptake ability results showed CBP/SB-NC could be internalized into RM-1 cells more efficient than CBP solution. After internalized by RM-1 cells, the gas-blasting release process was tested in acid environment. It was demonstrated that 5 mg/ml NaHCO₃ was optimal to achieve pH-responsive gas-blasting release. In vitro release results showed that CBP significantly rapid release in acid environment (pH 5.0) compared to neutral pH (pH 7.4) (P < 0.05). Meanwhile, TEM and the change of the concentration of H⁺ results exhibited that the explosion of CBP/SB₅-NC was more easily happened in lysosome acid environment (pH 5.0). The blasting release can accelerate CBP lysosome release to cytoplasm. Furthermore, the nucleus delivery results showed CBP/SB₅-NC can promote pH-triggered rapid nucleus delivery. And the results of Pt-DNA adduct assay showed that the binding efficiency between CBP and DNA of CBP/SB₅-NC was higher than CBP solution. At last, in vitro and in vivo anti-tumor efficacy proved that CBP/SB₅-NC could enhance anti-tumor activity for prostate cancer therapy. CBP/SB₅-NC also showed superior safety in vitro and in vivo by hemolysis assay and histopathological study. All of the results demonstrate that CBP/SB₅-NC would be an efficient gas-blasting release formulation to enhance prostate cancer treatment.

The effects of umbilical cord-derived macrophage exosomes loaded with cisplatin on the growth and drug resistance of ovarian cancer cells

Objective: To assess the feasibility of an exosome-based drug delivery platform for the potent chemotherapeutic agent cisplatin to treat ovarian cancer.Significance: Exosomes have recently been used as drug delivery vehicles because of their natural advantages. Platinum-resistant forms of ovarian cancer require novel drug delivery methods to improve patient outcomes.Methods: We developed and compared different methods of loading exosomes released by mononuclear M1 and M2 macrophages from umbilical cord blood with cisplatin. We characterized the morphology, drug capacity, method of cellular entry, and antitumor efficacy of the exosomes in vitro.Results: Disruption of the exosomal membrane by sonication facilitated a high loading efficiency. Importantly, incorporation of cisplatin into umbilical cord blood-derived M1 macrophage exosomes increased its cytotoxicity 3.3× in drug-resistant A2780/DDP cells and 1.4× in drug-sensitive A2780 cells over chemotherapy alone. Loading of cisplatin into M2 exosomes increased its cytotoxicity by nearly 1.7× in drug-resistant A2780/DDP cells and 1.4× in drug-sensitive A2780 cells.Conclusions: We conclude that cisplatin-loaded M1 exosomes are potentially powerful new tools for the delivery of chemotherapeutics to treat cancers regardless of drug resistance.

Current status of in vivo bioanalysis of nano drug delivery systems

The development of nano drug delivery systems (NDDSs) provides new approaches to fighting against diseases. The NDDSs are specially designed to serve as carriers for the delivery of active pharmaceutical ingredients (APIs) to their target sites, which would certainly extend the benefit of their unique physicochemical characteristics, such as prolonged circulation time, improved targeting and avoiding of drug-resistance. Despite the remarkable progress achieved over the last three decades, the understanding of the relationships between the in vivo pharmacokinetics of NDDSs and their safety profiles is insufficient. Analysis of NDDSs is far more complicated than the monitoring of small molecular drugs in terms of structure, composition and aggregation state, whereby almost all of the conventional techniques are inadequate for accurate profiling their pharmacokinetic behavior in vivo. Herein, the advanced bioanalysis for tracing the in vivo fate of NDDSs is summarized, including liquid chromatography tandem-mass spectrometry (LC-MS/MS), Förster resonance energy transfer (FRET), aggregation-caused quenching (ACQ) fluorophore, aggregation-induced emission (AIE) fluorophores, enzyme-linked immunosorbent assay (ELISA), magnetic resonance imaging (MRI), radiolabeling, fluorescence spectroscopy, laser ablation inductively coupled plasma MS (LA-ICP-MS), and size-exclusion chromatography (SEC). Based on these technologies, a comprehensive survey of monitoring the dynamic changes of NDDSs in structure, composition and existing form in system (i.e. carrier polymers, released and encapsulated drug) with recent progress is provided. We hope that this review will be helpful in appropriate application methodology for investigating the pharmacokinetics and evaluating the efficacy and safety profiles of NDDSs.

New Synthetic Peptides Conjugated to Gold Nanoclusters: Antibiotic Activity Against Escherichia coli O157:H7 and Methicillin-Resistant Staphylococcus aureus (MRSA)

Gold nanoclusters protected with bovine serum albumin (AuNC) can be used in multiple biomedical applications through functionalization with two new and bioactive peptides. Both cationic peptides sequences of 17 amino acids in length and the cysteine residue at its C-terminus were designed and synthesized. Peptides were obtained by solid phase synthesis using the Fmoc strategy. Peptides may be coupled via disulfide bonds to AuNC with hydrodynamic size ~ 2 nm ± 0.3 determined by dynamic light scattering and it had a zeta potential value equal to - 42 mV. Peptides named NBC2253 and NBC2254 were attached to the AuNC using N-succinimidyl-3-(2-pyridyl-dithiol) propionate as crosslinker agent. AuNC@NBC2253 was more active against methicillin-resistant Staphylococcus aureus (MIC50 6.5 µM) and AuNC@NBC2254 exhibited higher antimicrobial activity than the free peptides on Escherichia coli O157:H7 (MIC50 3.5 µM). No hemolysis was detected for any of the peptides. It is evidenced that these antimicrobial peptides conjugated to AuNC serve as promising agents to combat some multi-resistant bacterial strains and that the specific binding of these antimicrobial peptides to gold nanoclusters improves the interaction of these nanostructured systems with the biological target.

Improving Treatment Efficacy of In Situ Forming Implants via Concurrent Delivery of Chemotherapeutic and Chemosensitizer

P-glycoprotein (Pgp), a member of the ATP-binding cassette family, is one of the major causes of multidrug resistance in tumors. Current clinical treatments to overcome MDR involve the co-delivery of a Pgp inhibitor and a chemotherapeutic. A concern for this treatment that has led to varied clinical trial success is the associated systemic toxicities involving endogenous Pgp. Local drug delivery systems, such as in situ forming implants (ISFIs), alleviate this problem by delivering a high concentration of the drug directly to the target site without the associated systemic toxicities. ISFIs are polymeric drug solutions that undergo a phase transition upon injection into an aqueous environment to form a solid drug eluting depot allowing for a high initial intratumoral drug concentration. In this study, we have developed an ISFI capable of overcoming the Pgp resistance by co-delivering a chemotherapeutic, Doxorubicin (Dox), with a Pgp inhibitor, either Pluronic P85 or Valspodar (Val). Studies investigated in vitro cytotoxicity of Dox when combined with either Pgp inhibitor, effect of the inhibitors on release of Dox from implants in PBS, in vivo Dox distribution and retention in a subcutaneous flank colorectal murine tumor, and therapeutic response characterized by tumor growth curves and histopathology. Dox + Val showed a 4-fold reduction in the 50% lethal dose (LD₅₀) after 48 hours. Concurrent delivery of Dox and Val showed the greatest difference at 16 days post injection for both Dox penetration and retention. This treatment group had a 5-fold maximum Dox penetration compared to Dox alone ISFIs (0.53 ± 0.22 cm vs 0.11 ± 0.11 cm, respectively, from the center of the ISFI). Additionally, there was a 3-fold increase in normalized total intratumoral Dox intensity with the Dox + Val ISFIs compared to Dox alone ISFIs (0.54 ± 0.11 vs 0.18 ± 0.09, respectively). Dox + Val ISFIs showed a 2-fold reduction in tumor growth and a 27.69% increase in necrosis 20 days post-injection compared to Dox alone ISFIs. These findings demonstrate that co-delivery of Dox and Val via ISFI can avoid systemic toxicity issues seen with clinical Pgp inhibitors.

Therapeutic potentials of curcumin in the treatment of non-small-cell lung carcinoma

Non-small-cell lung carcinoma (NSCLC) is one of the most lethal malignancies that include more than 80% of lung cancer cases worldwide. During the past decades, plants and plant-derived products have attracted great interest in the treatment of various human diseases. Curcumin, the turmeric isolated natural phenolic compound, has shown a promising chemo-preventive and anticancer agent. Numerous studies have shown that curcumin delays the initiation and progression of NSCLC by affecting a wide range of molecular targets and cell signalling pathways including NF-kB, Akt, MAPKS, BCL-2, ROS and microRNAs (miRNAs). However, the poor oral bioavailability and low chemical stability of curcumin remain as major challenges in the utilisation of this compound as a therapeutic agent. Different analogs of curcumin and new delivery systems (e.g., micelles, nanoparticles and liposomes) provided promising solutions to overcome these obstacles and improve curcumin pharmacokinetic profile. The present review focuses on current reported studies about anti-NSCLC effects of curcumin. NSCLC involved miRNAs whose expression is regulated by curcumin has also been discussed. Furthermore, recent researches on the use of curcumin analogs and delivery systems to enhance the curcumin benefits in NSCLC are also described.

Influence of Hydrophobic Chains in Nanocarriers on Antitumor Efficacy of Docetaxel Nanoparticles

The composition of amphiphilic nanocarriers can affect the antitumor efficacy of drug-loaded nanoparticles and should be researched systematically. In this paper, to study the influence of hydrophobic chains, an amphiphilic copolymer (PEG₄₅PCL₁₇) and hydrophilic PEG (PEG₄₅) were utilized as nanocarriers to prepare docetaxel-loaded nanoparticles (DTX/PEG₄₅PCL₁₇ nanoparticles and DTX/PEG₄₅ nanoparticles) through an antisolvent precipitation method. The two DTX nanoparticles presented a similar drug loading content of approximately 60% and a sheet-like morphology. During the preparation procedure, the drug loading content affected the morphology of DTX nanoparticles, and the nanocarrier composition influenced the particle size. Compared with DTX/PEG₄₅ nanoparticles, DTX/PEG₄₅PCL₁₇ nanoparticles showed a smaller mean diameter and better in vitro and in vivo antitumor activity. The cytotoxicity of DTX/PEG₄₅PCL₁₇ nanoparticles against 4T1 cells was 1.31 μg mL^-1, 3.4-fold lower than that of DTX/PEG₄₅ nanoparticles. More importantly, DTX/PEG₄₅PCL₁₇ nanoparticles showed significantly higher antitumor activity in vivo, with an inhibition rate over 80%, 1.5-fold higher than that of DTX/PEG₄₅ nanoparticles. Based on these results, antitumor activity appears to be significantly affected by the particle size, which was determined by the composition of the nanocarrier. In summary, to improve antitumor efficacy, the amphiphilic structure should be considered and optimized in the design of nanocarriers.

Metastatic disease in head & neck oncology

The head and neck district represents one of the most frequent sites of cancer, and the percentage of metastases is very high in both loco-regional and distant areas. Prognosis refers to several factors: a) stage of disease; b) loco-regional relapses; c) distant metastasis. At diagnosis, distant metastases of head and neck cancers are present in about 10% of cases with an additional 20-30% developing metastases during the course of their disease. Diagnosis of distant metastases is associated with unfavorable prognosis, with a median survival of about 10 months. The aim of the present review is to provide an update on distant metastasis in head and neck oncology. Recent achievements in molecular profiling, interaction between neoplastic tissue and the tumor microenvironment, oligometastatic disease concepts, and the role of immunotherapy have all deeply changed the therapeutic approach and disease control. Firstly, we approach topics such as natural history, epidemiology of distant metastases and relevant pathological and radiological aspects. Focus is then placed on the most relevant clinical aspects; particular attention is reserved to tumours with distant metastasis and positive for EBV and HPV, and the oligometastatic concept. A substantial part of the review is dedicated to different therapeutic approaches. We highlight the role of immunotherapy and the potential effects of innovative technologies. Lastly, we present ethical and clinical perspectives related to frailty in oncological patients and emerging difficulties in sustainable socio-economical governance.

Melanin-Like Nanomaterials for Advanced Biomedical Applications: A Versatile Platform with Extraordinary Promise

Developing efficient, sustainable, and biocompatible high-tech nanoplatforms derived from naturally existing components in living organisms is highly beneficial for diverse advanced biomedical applications. Melanins are nontoxic natural biopolymers owning widespread distribution in various biosystems, possessing fascinating physicochemical properties and playing significant physiological roles. The multifunctionality together with intrinsic biocompatibility renders bioinspired melanin-like nanomaterials considerably promising as a versatile and powerful nanoplatform with broad bioapplication prospects. This panoramic Review starts with an overview of the fundamental physicochemical properties, preparation methods, and polymerization mechanisms of melanins. A systematical and well-bedded description of recent advancements of melanin-like nanomaterials regarding diverse biomedical applications is then given, mainly focusing on biological imaging, photothermal therapy, drug delivery for tumor treatment, and other emerging biomedicine-related implementations. Finally, current challenges toward clinical translation with an emphasis on innovative design strategies and future striving directions are rationally discussed. This comprehensive and detailed Review provides a deep understanding of the current research status of melanin-like nanomaterials and is expected to motivate further optimization of the design of novel tailorable and marketable multifunctional nanoplatforms in biomedicine.

Sensitizing activities of nitric oxide donors for cancer resistance to anticancer therapeutic drugs

Cancer is not a single disease but it constitutes a large variety of different types that are also different from each other phenotypically and molecularly. Although the standard treatments have resulted in clinical responses in a subset of patients, though, many patients relapse and no longer respond to further treatments. Hence, both the innate and adaptive resistance to treatments are the main challenges in today's treatment strategies. Noteworthy, several novel treatment strategies, particularly immunotherapies, used alone or in combination, have been developed and that have significantly improved the therapeutic response of many unresponsive cancer patients. Nevertheless, even with the latest new developments of therapeutics that were effective in a larger subset of patients, there is still an urgent need to treat the remaining unresponsive subset of patients. This requires the development of new targeting agents of superior antitumor activities that will lead to overcoming the unaffected resistance by current treatments. There has been accumulating evidence suggesting nitric oxide donors as such targeting agents and considering their pleiotropic antitumor activities, including both the reversal of chemo and immuno-resistance of various unresponsive resistant cancers. The in vitro and in vivo preclinical findings corroborate the sensitizing antitumor activities of nitric oxide donors. In addition, a few clinical findings with NO donors that have been applied in patients have corroborated their antitumor and sensitizing activities in combination with standard therapies. In this review, the role and underlying mechanisms by which nitric oxide donors sensitize cancer resistant cells to both chemotherapy and immunotherapy are briefly described.

Continuous synthesis of drug nanocrystals by solid hollow fiber cooling crystallization

Size reduction of drug with poor water solubility to nanoscale is an effective way to help improve the efficacy of drug delivery to the human body. A solid hollow fiber cooling crystallization technique has been adopted to continuously produce griseofulvin drug nanoparticles under modest conditions with accurate controllability. In the solid hollow fiber cooling crystallization device, drug solution flowed through the bores of solid hollow fibers while the cooling liquid was circulated counter-currently in the shell side of the device to cool down the drug solution in the tube side. Due to intense heat exchange between the cooling liquid and the drug solution through the thin fiber walls, the temperature of drug solution decreased rapidly so that drug nanoparticles were precipitated out from the solution by sudden reduction of solubility. Through variation of the experimental conditions and parameters, the mean size of the produced nanoparticles was regulated and controlled. The nanoparticles were dispersed uniformly, the chemical structure and bonds of prepared nanoparticles was the same with as-received griseofulvin. Both raw material and NPs the polymorph(s) present form I, the melting point was 220 °C. Drug dissolution testing was also executed to verify that nanocrystals have a higher dissolution profile.

Cross-Linked Pillar[6]arene Nanosponges Fabricated by the Use of a Supra-Amphiphilic Template: Cargo Encapsulation and Overcoming Multidrug Resistance

We report a general fabrication method for water-soluble pillar[n]arene nanosponges (NS) by the use of a supra-amphiphilic template. For the first time, a supra-amphiphilic template is used to conveniently control the size of host molecule-based NS. The intrinsic cavity of water-soluble pillar[6]arene could stably encapsulate dyes (acridine orange and indocyanine green) and antitumor drugs (doxorubicin hydrochloride and mitoxantrone) by host-guest interaction. NS could deliver antitumor drugs to cancer cells. Multidrug resistance (MDR) of cancer cells (MCF-7/ADR) is overcome by the use of NS with a ninefold reduction in the IC₅₀ value compared to that of the free drug (3.4 μM vs 34.4 μM). Mechanistic studies show that stable encapsulation of the antitumor drug is the reason to overcome MDR.