Scope of nanotechnology in ovarian cancer therapeutics

Exosomes derived from tumor adjacent fibroblasts efficiently target pancreatic tumors

The application of extracellular vesicles, particularly exosomes (EXs), is rapidly expanding in the field of medicine, owing to their remarkable properties as natural carriers of biological cargo. This study investigates utilization of exosomes derived from stromal cells of tumor adjacent normal tissues (NAF-EXs) for personalized medicine, which can be derived at the time of diagnosis by endoscopic ultrasound. Herein, we show that exosomes (EXs) derived from NAFs demonstrate differential bio-physical characteristics, efficient cellular internalization, drug loading efficiency, pancreatic tumor targeting and delivery of payloads. NAF-derived EXs (NAF-EXs) were used for loading ormeloxifene (ORM), a potent anti-cancer and desmoplasia inhibitor as a model drug. We found that ORM maintains normal fibroblast cell phenotype and renders them incompatible to be triggered for a CAF-like phenotype, which may be due to regulation of Ca2+ influx in fibroblast cells. NAF-EXs-ORM effectively blocked oncogenic signaling pathways involved in desmoplasia and epithelial mesenchymal transition (EMT) and repressed tumor growth in xenograft mouse model. In conclusion, our data suggests preferential tropism of NAF-EXs for PDAC tumors, thus imply feasibility of developing a novel personalized medicine for PDAC patients using autologous NAF-EXs for improved therapeutic outcome of anti-cancer drugs. Additionally, it provides the opportunity of utilizing this biological scaffold for effective therapeutics in combination with standard therapeutic regimen.

Preparation of Liposome Gel by Calcium Cross-Linking Induces the Long-Term Release of DOX to Improve the Antitumor Effect

Doxorubicin (DOX) is one of the most commonly used anticancer drugs; however, its clinical application is greatly limited due to its toxicity and chemotherapy resistance. The delivery of DOX by liposomes (Lipos) can improve the blood circulation time in vivo and reduce toxic side effects, but the drug's accumulation in the tumor is often insufficient for effective treatment. In this study, we present a calcium cross-linked liposome gel for the encapsulation of DOX, demonstrating its superior long-term release capabilities compared to conventional Lipos. By leveraging this enhanced long-term release, we can enhance drug accumulation within tumors, ultimately leading to improved antitumor efficacy. Lipos were prepared using the thin-film dispersion method in this study. We utilized the ion-responsiveness of glutathione-gelatin (GSH-GG) to form the gel outside the Lipos and named the nanoparticles coated with GSH-GG on the outside of Lipos as Lipos@GSH-GG. The average size of Lipos@GSH-GG was around 342.9 nm, with a negative charge of -25.6 mV. The in vitro experiments revealed that Lipos@GSH-GG exhibited excellent biocompatibility and slower drug release compared to conventional Lipos. Further analysis of cellular uptake and cytotoxicity demonstrated that Lipos@GSH-GG loading DOX (DOX&Lipos@GSH-GG) exhibited superior long-term release effects and lower toxic side effects compared to Lipos loading DOX (DOX&Lipos). Additionally, the findings regarding the long-term release effect in vivo and the tumor accumulation within tumor-bearing mice of Lipos@GSH-GG suggested that, compared to Lipos, it demonstrated superior long-term release capabilities and achieved greater drug accumulation within tumors. In vivo antitumor efficacy experiments showed that DOX&Lipos@GSH-GG demonstrated superior antitumor efficacy to DOX&Lipos. Our study highlights Lipos@GSH-GG as a promising nanocarrier with the potential to enhance efficacy and safety by means of long-term release effects and may offer an alternative approach for effective antitumor therapy in the future.

Nanoparticle-mediated therapeutic management in cholangiocarcinoma drug targeting: Current progress and future prospects

Patients with cholangiocarcinoma (CCA) often have an unfavorable prognosis because of its insidious nature, low resectability rate, and poor response to anticancer drugs and radiotherapy, which makes early detection and treatment difficult. At present, CCA has a five-year overall survival rate (OS) of only 5%, despite advances in therapies. New an increasing number of evidence suggests that nanoplatforms may play a crucial role in enhancing the pharmacological effects and in reducing both short- and long-term side effects of cancer treatment. This document reviews the advantages and shortcomings of nanoparticles such as liposomes, polymeric nanoparticle，inorganic nanoparticle, nano-metals and nano-alloys, carbon dots, nano-micelles, dendrimer, nano-capsule, bio-Nanomaterials in the diagnosis and treatment of CCA and discuss the current challenges in of nanoplatforms for CCA.

NIR irradiation-controlled drug release utilizing injectable hydrogels containing gold-labeled liposomes for the treatment of melanoma cancer

Drug-based chemotherapy is associated with serious side effects. We developed a chemotherapeutic system comprising a chitosan hydrogel (CH-HG) containing gold cluster-labeled liposomal doxorubicin (DOX) (CH-HG-GL_DOX) as an injectable drug depot system. CH-HG-GL_DOX can be directly injected into tumor tissue without a surgical procedure, allowing this system to act as a reservoir for liposomal DOX. CH-HG-GL_DOX enhanced the retention time of DOX in tumor tissue and controlled its release in response to near-infrared (NIR) irradiation, resulting in significant inhibition of tumor growth and reduced DOX-related toxicity. The combined effect of CH-HG-GL_DOX and poly (D,L-lactide-co-glycolic acid) nanoparticle-based vaccines increased cytotoxic CD8+ T cell immunity, leading to enhanced synergistic therapeutic efficacy. CH-HG-GL_DOX provides an advanced therapeutic approach for local drug delivery and controlled release of DOX, resulting in reduced toxicity. Here, we suggest a combination strategy for chemo- and immunotherapies, as well as in nanomedicine applications. STATEMENT OF SIGNIFICANCE: We developed an injectable hydrogel containing gold cluster-labeled liposomes for sustained drug release at the tumor site. Moreover, we demonstrated the combined therapeutic efficacy of a hydrogel system and a nanoparticle-based immunotherapeutic vaccine for melanoma cancer. Thus, we show a potential combination approach for chemo- and immunotherapies for cancer treatment.

Resveratrol potentially increased the tumoricidal effect of doxorubicin on SKOV3 cancer stem cells in vitro

Ovarian cancer is associated with a high percentage of recurrence of tumor and resistance to chemotherapy. Cancer stem cells (CSCs) form a rare population with a significant capacity to begin and expand malignant diseases. Eliminating the drug resistance of CSCs by factors that have fewer side effects to the patient is vital. To investigate the effect of resveratrol (RES) and doxorubicin (DOX) on drug resistance and apoptosis of CSCs; at the first, isolation of CSCs from SKOV3 ovarian carcinoma cells and their dosage adjustment (IC₅₀ ) with RES and DOX was performed. Then, isolated CSCs were treated with RES and DOX IC ₅₀ of 55 and 250 nM, respectively. Subsequently, their effects on drug resistance and cell death were evaluated using real-time polymerase chain reaction, rhodamine 123 uptakes. The results of the present study demonstrated that treatment of SKOV3 with 55 μM of RES and 250 nM of DOX simultaneously increased cell viability in CSCs to DOX after 24 and 48 hours by increasing the expression of Bcl-2-associated X protein (BAX) and caspase-3 genes, and decreased the expression and function of multidrug resistance protein 1 (MDR1) and multidrug resistance-associated protein 1 (MRP1) genes indicated by intracellular the rhodamine 123 content. Treatment of RES could increase the activity of DOX cell viability in CSCs originated from SKOV3 ovarian carcinoma and decrease drug resistance capacity to DOX.

Nanoceria-mediated delivery of doxorubicin enhances the anti-tumour efficiency in ovarian cancer cells via apoptosis

Nanocarriers are widely used for effective delivery of anticancer drugs to tumours with potential to improve cancer treatment. Here, we developed a nanoceria (CeO2)-based system for delivery of the anti-cancer drug doxorubicin (DOX) to human ovarian cancer cells. Negatively charged nanoceria could conjugate with the cationic DOX via electrostatic interaction under physiological conditions, forming DOX-loaded nanoceria (CeO2/DOX). CeO2/DOX particles displayed nearly spherical shapes, along with superior drug-loading content (22.41%), loading efficiency (99.51%), and higher cellular uptake and drug release behaviours compared to free DOX. Moreover, DOX was released faster from CeO2/DOX under reductive acidic conditions (pH 5.0, 10 mM glutathione) than under physiological conditions (pH 7.4). The initial intracellular DOX concentration was higher in the free DOX groups than in the CeO2/DOX groups, but quickly reduced to 25% of the initial concentration after 24-h culture. By contrast, CeO2/DOX showed sustained DOX release over time and maintained a high intracellular DOX concentration for up to 72 h. In vitro assays showed that CeO2/DOX exhibited higher cell proliferation inhibition and apoptosis compared with free DOX. These results highlight DOX-loaded nanoceria as a promising therapeutic agent for cancer treatment.

Self-assembled silk fibroin nanoparticles loaded with binary drugs in the treatment of breast carcinoma

Self-assembled nanoparticles of the natural polymer, silk fibroin (SF), are a very promising candidate in drug delivery due to their biocompatible and biodegradable properties. In this study, SF nanoparticles loaded with 5-fluorouracil (5-FU) and curcumin with size 217±0.4 nm and with a loading efficacy of 45% and 15% for 5-FU and curcumin, respectively, were prepared. The in vitro release effect of 5-FU and curcumin from nanoparticles was evaluated as ~100% and ~5%, respectively. It has been revealed that the application of such a nanodrug can increase the level of reactive oxygen species, which in turn induces apoptosis of cancer cells in vitro. Animal studies have shown that tumors could be noticeably reduced after being injected with the drug-entrapped nanoparticles. More apoptotic cells were found after 7 days of treatment with SF nanoparticles by a hematoxylin–eosin staining assay. These results demonstrate the future potential of nanoparticle-loaded binary drugs in the treatment of breast cancer.

Targeted therapy in ovarian cancer

Among female-specific cancers worldwide, ovarian cancer is the leading cause of death from gynecologic malignancy in the western world. Despite radical surgery and initial high response rates to first-line chemotherapy, up to 70% of patients experience relapses with a median progression-free survival of 12-18 months. There remains an urgent need for novel targeted therapies to improve clinical outcomes in ovarian cancer. This review aims to assess current understanding of targeted therapy in ovarian cancer and evaluate the evidence for targeting growth-dependent mechanisms involved in its pathogenesis. Of the many targeted therapies currently under evaluation, the most promising strategies developed thus far are antiangiogenic agents and PARP inhibitors.

Enhanced effect of photodynamic therapy in ovarian cancer using a nanoparticle drug delivery system

Nanoparticles are promising novel drug delivery carriers that allow tumor targeting and controlled drug release. In the present study, we prepared poly butyl-cyanoacrylate nanoparticles (PBCA-NP) entrapped with hypocrellin B (HB) to improve the effect of photodynamic therapy (PDT) in ovarian cancer. An ovarian cancer ascites model using Fischer 344 rats and PBCA-NP entrapped with HB (HB-PBCA-NP) were formed successfully. The pharmacodynamic characteristics and biodistribution of the HB-PBCA-NP system were evaluated by comparison with HB dimethyl sulfoxide (HB-DMSO) and testing at various time-points following intraperitoneal drug administration. HB-PBCA-NP-based PDT combined with cytoreductive surgery was then administrated to the tumor-bearing animals. Kaplan-Meier survival analysis was performed to assess the therapeutic effect of the nanoparticle system. The serum HB concentration peaked 4 h after drug administration in the nanoparticle system, and 1 h with HB-DMSO. The peak exposure time of tumor tissues was also extended (4 vs. 2 h), and PBCA-NP remained present for much longer than HB-DMSO. Although PDT combined with surgery prolonged the survival time significantly compared with surgery alone (84 days, P<0.05), there was no significant difference in the survival time of animals that received either HB-PBCA-NP- or HB-DMSO-based PDT after cytoreductive surgery (99 vs. 95 days, P=0.293). PBCA-NP exhibited potential advantages in controlled drug release and tumor targeting, which was beneficial for HB-based PDT. PDT combined with surgery prolonged the survival time, suggesting that this might be an alternative treatment option for ovarian cancer.

Polymeric nanoassemblies entrapping curcumin overcome multidrug resistance in ovarian cancer

The increasing emergence of multidrug-resistant (MDR) cells presents a challenge to effective cancer therapy. Curcumin (CUR) has multifunctional anticancer properties, but its clinical use has been limited by poor solubility. We developed biodegradable polymeric micelles entrapping CUR in order to improve its antitumor activity and to explore whether it could treat MDR cells. This delivery system produced small micelles with a high encapsulation efficiency, good stability, and slow release of CUR. CUR micelles showed cytotoxic effects in wild-type drug-sensitive A2780s and in paclitaxel-resistant A2780t ovarian adenocarcinoma cells. The concentration of free CUR that reduced cell viability by 50% (IC50) was 1.5 fold and 1.2 fold higher than that of CUR micelles in A2780s and A2780t cells, respectively. Cellular uptake studies indicated that delivery by micelles improved CUR uptake into both cell lines. Cell cycle analysis suggested that CUR micelles induced apoptosis and enhanced G2/M arrest. Overall, CUR micelles may provide a novel strategy to improve the clinical management of MDR ovarian cancer.

Nanoways to overcome docetaxel resistance in prostate cancer

Prostate cancer is the most common non-cutaneous malignancy in American men. Docetaxel is a useful chemotherapeutic agent for prostate cancer that has been available for over a decade, but the length of the treatment and systemic side effects hamper compliance. Additionally, docetaxel resistance invariably emerges, leading to disease relapse. Docetaxel resistance is either intrinsic or acquired by adopting various mechanisms that are highly associated with genetic alterations, decreased influx and increased efflux of drugs. Several combination therapies and small P-glycoprotein inhibitors have been proposed to improve the therapeutic potential of docetaxel in prostate cancer. Novel therapeutic strategies that may allow reversal of docetaxel resistance include alterations of enzymes, improving drug uptake and enhancement of apoptosis. In this review, we provide the most current docetaxel reversal approaches utilizing nanotechnology. Nanotechnology mediated docetaxel delivery is superior to existing therapeutic strategies and a more effective method to induce P-glycoprotein inhibition, enhance cellular uptake, maintain sustained drug release, and improve bioavailability.

The potentials of nanotechnology-based drug delivery system for treatment of ovarian cancer

Ovarian cancer is one of the leading causes for death of women. Every year the percentage of mortality rate is increasing day by day. Various chemotherapeutic agents are used to increase the survival rate of patients with ovarian cancer, but the available conventional dosage forms/marketed preparations are associated with several limitations. The use of nanotechnology in drug delivery contributes to their small size (10-100 nm), which improves the circulation and enables superior accumulation of therapeutic drugs at the tumor sites. In future, the use of nanotechnology will enable passive targeting and further improvements can be made using targeting moieties.

Effect of engineered TiO2 and ZnO nanoparticles on erythrocytes, platelet-rich plasma and giant unilamelar phospholipid vesicles

Background

Massive industrial production of engineered nanoparticles poses questions about health risks to living beings. In order to understand the underlying mechanisms, we studied the effects of TiO₂ and ZnO agglomerated engineered nanoparticles (EPs) on erythrocytes, platelet-rich plasma and on suspensions of giant unilamelar phospholipid vesicles.

Results

Washed erythrocytes, platelet-rich plasma and suspensions of giant unilamelar phospholipid vesicles were incubated with samples of EPs. These samples were observed by different microscopic techniques. We found that TiO₂ and ZnO EPs adhered to the membrane of washed human and canine erythrocytes. TiO₂ and ZnO EPs induced coalescence of human erythrocytes. Addition of TiO₂ and ZnO EPs to platelet-rich plasma caused activation of human platelets after 24 hours and 3 hours, respectively, while in canine erythrocytes, activation of platelets due to ZnO EPs occurred already after 1 hour. To assess the effect of EPs on a representative sample of giant unilamelar phospholipid vesicles, analysis of the recorded populations was improved by applying the principles of statistical physics. TiO₂ EPs did not induce any notable effect on giant unilamelar phospholipid vesicles within 50 minutes of incubation, while ZnO EPs induced a decrease in the number of giant unilamelar phospholipid vesicles that was statistically significant (p < 0,001) already after 20 minutes of incubation.

Conclusions

These results indicate that TiO₂ and ZnO EPs cause erythrocyte aggregation and could be potentially prothrombogenic, while ZnO could also cause membrane rupture.

Enhanced apoptosis of ovarian cancer cells via nanocarrier-mediated codelivery of siRNA and doxorubicin

A folate conjugated ternary copolymer, FA–PEG–PEI–PCL, of poly(ethylene glycol) (PEG), poly(ethylene imine) (PEI), and poly(ɛ-caprolactone) (PCL) was synthesized. The copolymer self-assembled into cationic micelles capable of co-delivering siRNA and the anticancer drug doxorubicin (DOX). This dual functional nanocarrier demonstrated low cytotoxicity and high performance in drug/siRNA delivery. Upon the codelivery of siRNA, targeting the Bcl-2 gene, and DOX, using the folate-targeted nanocarrier, DOX-induced apoptosis in the skov-3 cells overexpressing folate receptor was significantly enhanced through a mechanism of downregulating the antiapoptotic protein Bcl-2, while simultaneously upregulating the proapoptotic protein Bax. This work suggested that the combination of Bcl-2 siRNA and DOX therapies is feasible, based on our dual functional nanocarrier, which set up a good basis for a future in vivo test.

Curcumin nanoformulations: a future nanomedicine for cancer

Curcumin, a natural diphenolic compound derived from turmeric Curcuma longa, has proven to be a modulator of intracellular signaling pathways that control cancer cell growth, inflammation, invasion and apoptosis, revealing its anticancer potential. In this review, we focus on the design and development of nanoparticles, self-assemblies, nanogels, liposomes and complex fabrication for sustained and efficient curcumin delivery. We also discuss the anticancer applications and clinical benefits of nanocurcumin formulations. Only a few novel multifunctional and composite nanosystem strategies offer simultaneous therapy as well as imaging characteristics. We also summarize the challenges to developing curcumin delivery platforms and up-to-date solutions for improving curcumin bioavailability and anticancer potential for therapy.

Progesterone signaling mediated through progesterone receptor membrane component-1 in ovarian cells with special emphasis on ovarian cancer

Various ovarian cell types including granulosa cells and ovarian surface epithelial cells express the progesterone (P4) binding protein, progesterone receptor membrane component-1 (PGRMC1). PGRMC1 is also expressed in ovarian tumors. PGRMC1 plays an essential role in promoting the survival of both normal and cancerous ovarian cell in vitro. Given the clinical significance of factors that regulate the viability of ovarian cancer, this review will focus on the role of PGRMC1 in ovarian cancer, while drawing insights into the mechanism of PGRMC1's action from cell lines derived from healthy ovaries as well as ovarian tumors. Studies using PGRMC1siRNA demonstrated that P4's ability to inhibit ovarian cells from undergoing apoptosis in vitro is dependent on PGRMC1. To confirm the importance of PGRMC1, the ability of PGRMC1-deplete ovarian cancer cell lines to form tumors in intact nude mice was assessed. Compared to PGRMC1-expressing ovarian cancer cells, PGRMC1-deplete ovarian cancer cells formed tumors in fewer mice (80% compared to 100% for controls). Moreover, the number of tumors derived from PGRMC1-deplete ovarian cancer cells was 50% of that observed in controls. Finally, the tumors that formed from PGRMC1-deplete ovarian cancer cells were about a fourth the size of tumors derived from ovarian cancer cells with normal levels of PGRMC1. One reason for PGRMC1-deplete tumors being smaller is that they had a poorly developed microvasculature system. How PGRMC1 regulates cell viability and in turn tumor growth is not known but part of the mechanism likely involves the regulation of genes that promote cell survival and inhibit apoptosis.

Design and engineering of nanogels for cancer treatment

Here, we provide a comprehensive insight into current advances in the use of nanogel-mediated chemotherapy for cancer treatment. Nanogels are composed of cross-linked three-dimensional polymer chain networks that are formed via covalent linkages or self-assembly processes. The porosity between the cross-linked networks of nanogels not only provides an ideal reservoir for loading drugs, oligonucleotides and imaging agents, but also protects them from environmental degradation and hazards. Here, we focus mainly on novel synthetic strategies and key considerations in the design of nanogel-based drug delivery systems for controlled and targeted cancer therapeutic applications.

IBC's 21st Annual Antibody Engineering and 8th Annual Antibody Therapeutics International Conferences and 2010 Annual Meeting of the Antibody Society. December 5-9, 2010, San Diego, CA USA

The 21^st Annual Antibody Engineering and 8^th Annual Antibody Therapeutics international conferences, and the 2010 Annual Meeting of The Antibody Society, organized by IBC Life Sciences with contributions from The Antibody Society and two Scientific Advisory Boards, was held December 5–9, 2010 in San Diego, CA. The conferences featured over 100 presentations and 100 posters, and included a pre-conference workshop on deep-sequencing of antibody genes. The total number of delegates exceeded 800, which set a new attendance record for the conference.

The conferences were organized with a focus on antibody engineering only on the first day and a joint engineering/therapeutics session on the last day. Delegates could select from presentations that occurred in two simultaneous sessions on days 2 and 3. Day 1 included presentations on neutralizing antibodies and the identification of vaccine targets, as well as a historical overview of 20 years of phage display utilization. Topics presented in the Antibody Engineering sessions on day 2 and 3 included antibody biosynthesis, structure and stability; antibodies in a complex environment; antibody half-life; and targeted nanoparticle therapeutics. In the Antibody Therapeutics sessions on days 2 and 3, preclinical and early stage development and clinical updates of antibody therapeutics, including TRX518, SYM004, MM111, PRO140, CVX-241, ASG-5ME, U3-1287 (AMG888), R1507 and trastuzumab emtansine, were discussed and perspectives were provided on the development of biosimilar and biobetter antibodies, including coverage of regulatory and intellectual property issues. The joint engineering/therapeutics session on the last day focused on bispecific and next-generation antibodies. Summaries of most of the presentations are included here, but, due to the large number of speakers, it was not possible to include summaries for every presentation.

Delegates enjoyed the splendid views of the San Diego Bay and proximity to the Gaslamp Quarter provided by the venue. The 22^nd Annual Antibody Engineering and 9th Annual Antibody Therapeutics conferences, and the 2011 Annual Meeting of The Antibody Society, are planned for December 5–8, 2011 at the same location in San Diego, and will include two two-day short courses on Introduction to Antibody Engineering and Protein Characterization for Biotechnology Product Development.