Multifunctional PEGylated Albumin/IR780/Iron Oxide Nanocomplexes for Cancer Photothermal Therapy and MR Imaging

A novel combined therapeutic strategy of Nano-EN-IR@Lip mediated photothermal therapy and stem cell inhibition for gastric cancer

Recurrence and metastasis of gastric cancer is a major therapeutic challenge for treatment. The presence of cancer stem cells (CSCs) is a major obstacle to the success of current cancer therapy, often leading to treatment resistance and tumor recurrence and metastasis. Therefore, it is important to develop effective strategies to eradicate CSCs. In this study, we developed a combined therapeutic strategy of photothermal therapy (PTT) and gastric cancer stem cells (GCSCs) inhibition by successfully synthesizing nanoliposomes loaded with IR780 (photosensitizer) and EN4 (c-Myc inhibitor). The nanocomposites are biocompatible and exhibit superior photoacoustic (PA) imaging properties. Under laser irradiation, IR780-mediated PTT effectively and rapidly killed tumor cells, while EN4 synergistically inhibited the self-renewal and stemness of GCSCs by suppressing the expression and activity of the pluripotent transcription factor c-Myc, preventing the tumor progression of gastric cancer. This Nano-EN-IR@Lip is expected to be a novel clinical nanomedicine for the integration of gastric cancer diagnosis, treatment and prevention.

Tumor-activated targetable photothermal chemotherapy using IR780/zoledronic acid-containing hybrid polymeric nanoassemblies with folate modification to treat aggressive breast cancer

To effectively treat aggressive breast cancer by tumor-activated targetable photothermal chemotherapy, in this work, folate (FA)-modified hybrid polymeric nanoassemblies (HPNs) with a poly(ethylene glycol) (PEG)-detachable capability are developed as vehicles for tumor-targeted co-delivery of IR780, a lipophilic photothermal reagent, and zoledronic acid (ZA), a hydrophilic chemotherapy drug. Through hydrophobic interaction-induced co-assembly, IR780 molecules and ZA/poly(ethylenimine) (PEI) complexes were co-encapsulated into a poly(lactic-co-glycolic acid) (PLGA)-rich core stabilized by the amphiphilic FA-modified D-α-tocopheryl poly(ethylene glycol) succinate (FA-TPGS) and acidity-sensitive PEG-benzoic imine-octadecane (C18) (PEG-b-C18) conjugates. The developed FA-ZA/IR780@HPNs with high ZA and IR780 payloads not only showed excellent colloidal stability in a serum-containing milieu, but also promoted IR780-based photostability and photothermal conversion efficiency. Furthermore, for FA-ZA/IR780@HPNs under simulated physiological conditions, the premature leakage of IR780 and ZA molecules was remarkably declined. In a mimetic acidic tumor microenvironment, the uptake of FA-ZA/IR780@HPNs by FA receptor-overexpressed 4T1 breast cancer cells was remarkably promoted by PEG detachment combined with FA receptor-mediated endocytosis, thus effectively hindering migration of cancer cells and augmenting the anticancer efficacy of photothermal chemotherapy. Notably, the in vivo studies demonstrated that the FA-ZA/IR780@HPNs largely deposited at 4T1 tumor sites and profoundly suppressed tumor growth and metastasis without severe systemic toxicity upon near infrared (NIR)-triggered IR780-mediated hyperthermia integrated with ZA chemotherapy. This work presents a practical strategy to treat aggressive breast tumors with tumor-triggered targetable photothermal chemotherapy using FA-ZA/IR780@HPNs.

Carbohydrate polymers-based surface modified nano delivery systems for enhanced target delivery to colon cancer - A review

Carbohydrate polymers-based surface-modified nano-delivery systems have gained significant attention in recent years for enhancing targeted delivery to colon cancer. These systems leverage carbohydrate polymers' unique properties, such as biocompatibility, biodegradability, and controlled release. These properties make them suitable candidates for drug delivery applications. Nano-delivery systems loaded with bioactive compounds are well-studied for targeted colorectal cancer delivery. However, those drugs' target reach is still limited in various nano-delivery systems. To overcome this limitation, surface modification of nanoparticles with carbohydrate polymers like chitosan, pectin, alginate, and guar gum showed enhanced target-reaching capacity along with enhanced anticancer efficacy. Recently, a chitosan-decorated PLGA nanoparticle was constructed with tannic acid and vitamin E and showed long-term release of specific targets along with higher anticancer efficacy. Similarly, Chitosan-conjugated glucuronic acid-coated silica nanoparticles loaded with capecitabine were studied against colon cancer and found to be the pH-responsive controlled release of capecitabine with higher anticancer efficacy. Surface-modified carbohydrate polymers have promising potential for improving colon cancer target delivery. By leveraging the unique properties of these polymers, such as surface modification, pH responsiveness, mucoadhesion, controlled drug release, and combination therapy, researchers are working toward developing more effective and targeted treatment strategies for colon cancer.

Nanoparticles for imaging-guided photothermal therapy of colorectal cancer

Colorectal cancer (CRC) is one of the most common malignancies with a high mortality rate worldwide. While surgery, chemotherapy, and radiotherapy have shown some effectiveness in improving survival rates, they come with drawbacks such as side effects and harm to healthy tissues. The theranostic approach, which integrates the processes of cancer diagnosis and treatment, can minimize biological side effects. Photothermal therapy (PTT) is an emerging treatment method that usages light-sensitive agents to generate heat at the tumor site and induce thermal erosion. The development of nanotechnology for CRC treatment using imaging-guided PTT has garnered significant. Nanoparticles with suitable physical and chemical properties can enhance the efficiency of cancer diagnosis and PTT. This approach enables the monitoring of cancer treatment progress and safeguards healthy tissues. In this article, we concisely introduce the application of metal nanoparticles, polymeric nanoparticles, and carbon nanoparticles in imaging-guided PTT of colorectal cancer.

IONPs-Based Medical Imaging in Cancer Care: Moving Beyond Traditional Diagnosis and Therapeutic Assessment

Cancer-related burden of morbidity and mortality is rapidly rising worldwide. Medical imaging plays an important role in every phase of cancer management, including diagnosis, staging, treatment planning and evaluation. Iron oxide nanoparticles (IONPs) could serve as contrast agents or labeling agents to enhance the identification and visualization of pathological tissues as well as target cells. Multimodal or multifunctional imaging can be easily acquired by modifying IONPs with other imaging agents or functional groups, allowing the accessibility of combined imaging techniques and providing more comprehensive information for cancer care. To date, IONPs-enhanced medical imaging has gained intensive application in early diagnosis, monitoring treatment as well as guiding radio-frequency ablation, sentinel lymph node dissection, radiotherapy and hyperthermia therapy. Besides, IONPs mediated imaging is also capable of promoting the development of anti-cancer nanomedicines through identifying patients potentially sensitive to nanotherapeutics. Based on versatile imaging modes and application fields, this review highlights and summarizes recent research advances of IONPs-based medical imaging in cancer management. Besides, currently existing challenges are also discussed to provide perspectives and advices for the future development of IONPs-based imaging in cancer management.

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.

Multiplexed imaging in oncology

In oncology, technologies for clinical molecular imaging are used to diagnose patients, establish the efficacy of treatments and monitor the recurrence of disease. Multiplexed methods increase the number of disease-specific biomarkers that can be detected simultaneously, such as the overexpression of oncogenic proteins, aberrant metabolite uptake and anomalous blood perfusion. The quantitative localization of each biomarker could considerably increase the specificity and the accuracy of technologies for clinical molecular imaging to facilitate granular diagnoses, patient stratification and earlier assessments of the responses to administered therapeutics. In this Review, we discuss established techniques for multiplexed imaging and the most promising emerging multiplexing technologies applied to the imaging of isolated tissues and cells and to non-invasive whole-body imaging. We also highlight advances in radiology that have been made possible by multiplexed imaging.

Photo-induced processes of iron oxide nanoparticles to enhance laser therapy

Nanoparticles are used as drug carriers to increase the selectivity and effectiveness of therapy, as well as for combined therapy that utilizes different effects. Iron oxide nanoparticles are promising in this aspect. Due to magnetic properties, they can be used as a contrast agent for magnetic resonance imaging. Also, iron oxide nanoparticles could be coated with a photosensitizer for photodynamic therapy and their laser or magnetic heating can be used for phototherapy. Local enhancement of the electromagnetic field near iron oxide nanoparticles can increase the fluorescence intensity of photosensitizers and the efficiency of singlet oxygen generation. This paper presents the results of a study of iron oxide nanoparticles focused on the photophysical aspects of the formation of “hot spots” under laser irradiation. The photoinduced effects of iron oxide nanoparticles observed in in vitro experiments lead to the rupture of lysosomes. Theoretical modeling showed that the heating of iron oxide nanoparticles with a radius of 35 nm under the action of laser radiation is about 89°C and 19°C for wavelengths of 458 and 561 nm, respectively. Local field enhancement occurs in pairs of nanoparticles of various sizes and strongly depends on the distance between them. The maximum gain is achieved at small distances between nanoparticles. For a dimer of nanoparticles with radii of 10 and 35 nm at a distance of 1 nm, an enhancement factor of two orders of magnitude was obtained. The investigated phenomenon of «hot spots» is in demand for precision therapy, because the photo-induced processes occur at small distances between nanoparticles, in areas of their high accumulation.

Trends in targeted delivery of nanomaterials in colon cancer diagnosis and treatment

Colon cancer is an adenocarcinoma, which subsequently develops into malignant tumors, if not treated properly. The current colon cancer therapy mainly revolves around chemotherapy, radiotherapy and surgery, but the search continues for more effective interventions. With the advancement of nanoparticles (NPs), it is now possible to diagnose and treat colon cancers with different types, shapes, and sizes of NPs. Nanoformulations such as quantum dots, iron oxide, polymeric NPs, dendrimers, polypeptides, gold NPs, silver NPs, platinum NPs, and cerium oxide have been either extensively used alone or in combination with other nanomaterials or drugs in colon cancer diagnosis, and treatments. These nanoformulations possess high biocompatibility and bioavailability, which makes them the most suitable candidates for cancer treatment. The size and shape of NPs are critical to achieving an effective drug delivery in cancer treatment and diagnosis. Most NPs currently are under different testing phases (in vitro, preclinical, and clinical), whereas some of them have been approved for therapeutic applications. We have comprehensively reviewed the recent advances in the applications of NPs-based formulations in colon cancer diagnosis and treatment.

Hyaluronic acid functionalized biodegradable mesoporous silica nanocomposites for efficient photothermal and chemotherapy in breast cancer

Chemotherapy is one of conventional treatment methods for breast cancer, but drug toxicity and side effects have severely limited its clinical applications. Photothermal therapy has emerged as a promising method that, upon combination with chemotherapy, can better treat breast cancer. In this context, a biodegradable mesoporous silica nanoparticle (bMSN NPs) system was developed for loading doxorubicin (DOX) and IR780, to be potentially applied in the treatment of breast cancer. IR780 is encapsulated in the pores of bMSN NPs by hydrophobic adsorption, while DOX is adsorbed on the surface of the bMSN NPs by hyaluronic acid electrostatically, to form the bMID NPs. Transmission electron microscopy, fluorescence spectrum and UV absorption spectrum are used to prove the successful encapsulation of IR780 and the loading of DOX. In vitro experiments have shown bMID NPs present an excellent therapeutic effect on breast cancer cells. In vivo fluorescence imaging results have indicated that bMID NPs can accumulate in tumor sites gradually and achieve in vivo long-term circulation and continuous drug release. Furthermore, bMID NPs have provided obvious antitumor effects in breast cancer mouse models, thus evolving as an efficient platform for breast cancer therapy.

Injectable in situ forming hydrogels incorporating dual-nanoparticles for chemo-photothermal therapy of breast cancer cells

Chemo-photothermal therapy (chemo-PTT) mediated by nanomaterials holds a great potential for cancer treatment. However, the tumor uptake of the systemically administered nanomaterials was recently found to be below 1%. To address this limitation, the development of injectable tridimensional polymeric matrices capable of delivering nanomaterials directly into the tumor site appears to be a promising approach. In this work, an injectable in situ forming ionotropically crosslinked chitosan-based hydrogel co-incorporating IR780 loaded nanoparticles (IR/BPN) and Doxorubicin (DOX) loaded nanoparticles (DOX/TPN) was developed for application in breast cancer chemo-PTT. The produced hydrogels (IR/BPN@Gel and IR/BPN+DOX/TPN@Gel) displayed suitable physicochemical properties and produced a temperature increase of about 9.1 °C upon exposure to Near Infrared (NIR) light. As importantly, the NIR-light exposure also increased the release of DOX from the hydrogel by 1.7-times. In the in vitro studies, the combination of IR/BPN@Gel with NIR light (photothermal therapy) led to a reduction in the viability of breast cancer cells to 35%. On the other hand, the non-irradiated IR/BPN+DOX/TPN@Gel (chemotherapy) only diminished cancer cells' viability to 85%. In contrast, the combined action of IR/BPN+DOX/TPN@Gel and NIR light reduced cancer cells' viability to about 9%, demonstrating its potential for breast cancer chemo-PTT.

Fe3O4 magnetic nanoparticles ameliorate albumin-induced tubulointerstitial fibrosis by autophagy related to Rab7

Albuminuria is a primary feature in patients with CKD and an important contributor to tubulointerstitial fibrosis (TIF) development. Autophagy has been considered to be involved in renal tubular injury caused by albuminuria. Fe₃O₄ magnetic nanoparticles are related to many cellular activities, such as autophagy and inflammation. Rab7, a molecule involved in both endocytosis and autophagy, has been identified to protect renal tubular epithelial cells from albumin by regulating autophagy and MMP-2 activity in the early stage of albumin stimulation, but its role in the advanced stage is still unclear. Therefore, to investigate the effect of Fe₃O₄ magnetic nanoparticles on chronic renal tubular injury induced by excess albumin and to further determine the specific role of Rab7, we established a mouse model of TIF by intravenous injection of cationic bovine serum albumin (C-BSA) in Rab7-overexpressing transgenic mice. Our data revealed the decreased autophagy level, weakened MMP-2 activity and exacerbated renal tubular injury in these BSA-overloaded mice; furthermore, the degree of injury was more serious in Rab7-overexpressing transgenic mice. However, the application of Fe₃O₄ magnetic albumin nanoparticles (Fe₃O₄@BSA) enhanced MMP-2 activity and alleviated renal tubular injury, and these changes were mediated by an autophagy-dependent mechanism. Taken together, our results indicated that long-term albumin stimulation combined with overexpression of Rab7 could further decrease MMP-2 activity, exacerbate renal tubular injury and accelerate the development of TIF. Fe₃O₄@BSA could be a promising targeted tool for the management of CKD patients.

Tumor microenvironment-responsive and oxygen self-sufficient oil droplet nanoparticles for enhanced photothermal/photodynamic combination therapy against hypoxic tumors

The combination of photothermal and photodynamic therapy (PTT/PDT) shows pronounced potential as a prominent therapeutic strategy for tumor treatment. However, the efficacy is limited by insufficient tumor-targeted delivery of PTT and PDT reagents and the hypoxic nature of the tumor microenvironment. To overcome these limitations, tumor acidity-responsive lipid membrane-enclosed perfluorooctyl bromide oil droplet nanoparticles (NPs) surface modified with N-acetyl histidine-modified D-α-tocopheryl polyethylene glycol 1000 succinate (PFOB@IMHNPs) were developed, capable of co-delivering oxygen, IR780 (a photothermal agent) and mTHPC (a photodynamic sensitizer) into tumors. Through self-sufficient oxygen transportation in combination with promotion of cellular uptake upon acid-triggered generation of surface positive charge, the PFOB@IMHNPs effectively delivered IR780 and mTHPC and produced singlet oxygen within hypoxic TRAMP-C1 cells following exposure to irradiation at 660 nm. This led to effective killing of hypoxic cancer cells in vitro. Importantly, when irradiation at 808 and 660 nm was carried out, PT/PD combination therapy utilizing PFOB@IMHNPs dramatically suppressed the growth of TRAMP-C1 tumors through effective tumor-targeted cargo delivery and relief of tumor hypoxia. Our results suggest the high potential of the PFOB@IMHNPs developed in this study in clinical application for cancer treatment.

Theranostic Nanoparticles with Aggregation-Induced Emission and MRI Contrast Enhancement Characteristics as a Dual-Modal Imaging Platform for Image-Guided Tumor Photodynamic Therapy

Introduction

Advanced tumor-targeted theranostic nanoparticles play a key role in tumor diagnosis and treatment research. In this study, we developed a multifunctional theranostic platform based on an amphiphilic hyaluronan/poly-(N-ε-carbobenzyloxy-L-lysine) derivative (HA-g-PZLL), superparamagnetic iron oxide (SPIO) and aggregation-induced emission (AIE) nanoparticles for tumor-targeted magnetic resonance (MR) and fluorescence (FL) dual-modal image-guided photodynamic therapy (PDT).

Materials and Methods

The amphiphilic hyaluronan acid (HA) derivative HA-g-PZLL was synthesized by grafting hydrophobic poly-(N-ε-carbobenzyloxy-L-lysine) (PZLL) blocks onto hyaluronic acid by a click conjugation reaction. The obtained HA-g-PZLLs self-assembled into nanoparticles in the presence of AIE molecules and SPIO nanoparticles to produce tumor-targeted theranostic nanoparticles (SPIO/AIE@HA-g-PZLLs) with MR/FL dual-modal imaging ability. Cellular uptake of the theranostic nanoparticles was traced by confocal laser scanning microscopy (CLSM), flow cytometry and Prussian blue staining. The intracellular reactive oxygen species (ROS) generation characteristics of the theranostic nanoparticles were evaluated with CLSM and flow cytometry. The effect of PDT was evaluated by cytotoxicity assay. The dual-mode imaging ability of the nanoparticles was evaluated by a real-time near-infrared fluorescence imaging system and magnetic resonance imaging scanning.

Results

The resulting theranostic nanoparticles not only emit red fluorescence for high-quality intracellular tracing but also effectively produce singlet oxygen for photodynamic tumor therapy. In vitro cytotoxicity experiments showed that these theranostic nanoparticles can be efficiently taken up and are mainly present in the cytoplasm of HepG2 cells. After internalization, these theranostic nanoparticles showed serious cytotoxicity to the growth of HepG2 cells after white light irradiation.

Discussion

This work provides a simple method for the preparation of theranostic nanoparticles with AIE characteristics and MR contrast enhancement, and serves as a dual-modal imaging platform for image-guided tumor PDT.

Recent advances in theranostic polymeric nanoparticles for cancer treatment: A review

Nanotheranostics is fast-growing pharmaceutical technology for simultaneously monitoring drug release and its distribution, and to evaluate the real time therapeutic efficacy through a single nanoscale for treatment and diagnosis of deadly disease such as cancers. In recent two decades, biodegradable polymers have been discovered as important carriers to accommodate therapeutic and medical imaging agents to facilitate construction of multi-modal formulations. In this review, we summarize various multifunctional polymeric nano-sized formulations such as polymer-based super paramagnetic nanoparticles, ultrasound-triggered polymeric nanoparticles, polymeric nanoparticles bearing radionuclides, and fluorescent polymeric nano-sized formulations for purpose of theranostics. The use of such multi-modal nano-sized formulations for near future clinical trials can assist clinicians to predict therapeutic properties (for instance, depending upon the quantity of drug accumulated at the cancerous site) and observed the progress of tumor growth in patients, thus improving tailored medicines.

Prototypic Heptamethine Cyanine Incorporating Nanomaterials for Cancer Phototheragnostic

Developing technologies that allow the simultaneous diagnosis and treatment of cancer (theragnostic) has been the quest of numerous interdisciplinary research teams. In this context, nanomaterials incorporating prototypic near infrared (NIR)-light responsive heptamethine cyanines have been showing very promising results for cancer theragnostic. The precisely engineered features of these nanomaterials endow them with the ability to achieve a high tumor accumulation, enabling a tumor's visualization by NIR fluorescence and photoacoustic imaging modalities. Upon interaction with NIR light, the tumor-homed heptamethine cyanine-incorporating nanomaterials can also produce a photothermal/photodynamic effect with a high spatio-temporal resolution and minimal side effects, leading to an improved therapeutic outcome. This progress report analyses the application of nanomaterials incorporating prototypic NIR-light responsive heptamethine cyanines (IR775, IR780, IR783, IR797, IR806, IR808, IR820, IR825, IRDye 800CW, and Cypate) for cancer photothermal therapy, photodynamic therapy, and imaging. Overall, the continuous development of nanomaterials incorporating the prototypic NIR absorbing heptamethine cyanines will cement their phototheragnostic capabilities.

Non-invasive In Vivo Imaging of Cancer Using Surface-Enhanced Spatially Offset Raman Spectroscopy (SESORS)

Rationale: The goal of imaging tumors at depth with high sensitivity and specificity represents a significant challenge in the field of biomedical optical imaging. 'Surface enhanced Raman scattering' (SERS) nanoparticles (NPs) have been employed as image contrast agents and can be used to specifically target cells in vivo. By tracking their unique "fingerprint" spectra, it becomes possible to determine their precise location. However, while the detection of SERS NPs is very sensitive and specific, conventional Raman spectroscopy imaging devices are limited in their inability to probe through tissue depths of more than a few millimetres, due to scattering and absorption of photons by biological tissues. Here, we combine the use of "Spatially Offset Raman spectroscopy" (SORS) with that of "surface-enhanced resonance Raman spectroscopy" (SERRS) in a technique known as "surface enhanced spatially offset resonance Raman spectroscopy" (SESO(R)RS) to image deep-seated glioblastoma multiforme (GBM) tumors in vivo in mice through the intact skull. Methods: A SORS imaging system was built in-house. Proof of concept SORS imaging was achieved using a PTFE-skull-tissue phantom. Imaging of GBMs in the RCAS-PDGF/N-tva transgenic mouse model was achieved through the use of gold nanostars functionalized with a resonant Raman reporter to create SERRS nanostars. These were then encapsulated in a thin silica shell and functionalized with a cyclic-RGDyK peptide to yield integrin-targeting SERRS nanostars. Non-invasive in vivo SORS image acquisition of the integrin-targeted nanostars was then performed in living mice under general anesthesia. Conventional non-SORS imaging was used as a direct comparison. Results: Using a low power density laser, GBMs were imaged via SESORRS in mice (n = 5) and confirmed using MRI and histopathology. The results demonstrate that via utilization of the SORS approach, it is possible to acquire clear and distinct Raman spectra from deep-seated GBMs in mice in vivo through the skull. SESORRS images generated using classical least squares outlined the tumors with high precision as confirmed via MRI and histology. Unlike SESORRS, conventional Raman imaging of the same areas did not provide a clear delineation of the tumor. Conclusion: To the best of our knowledge this is the first report of in vivo SESO(R)RS imaging. In a relevant brain tumor mouse model we demonstrate that this technique can overcome the limitations of conventional Raman imaging with regards to penetration depth. This work therefore represents a significant step forward in the potential clinical translation of SERRS nanoparticles for high precision cancer imaging.

Surface-enhanced Resonance Raman Scattering Nanoprobe Ratiometry for Detecting Microscopic Ovarian Cancer via Folate Receptor Targeting

Ovarian cancer represents the deadliest gynecologic malignancy. Most patients present at an advanced stage (FIGO stage III or IV), when local metastatic spread has already occurred. However, ovarian cancer has a unique pattern of metastatic spread, in that tumor implants are initially contained within the peritoneal cavity. This feature could enable, in principle, the complete resection of tumor implants with curative intent. Many of these metastatic lesions are microscopic, making them hard to identify and treat. Neutralizing such micrometastases is believed to be a major goal towards eliminating tumor recurrence and achieving long-term survival. Raman imaging with surface enhanced resonance Raman scattering nanoprobes can be used to delineate microscopic tumors with high sensitivity, due to their bright and bioorthogonal spectral signatures. Here, we describe the synthesis of two 'flavors' of such nanoprobes: an antibody-functionalized one that targets the folate receptor - overexpressed in many ovarian cancers - and a non-targeted control nanoprobe, with distinct spectra. The nanoprobes are co-administered intraperitoneally to mouse models of metastatic human ovarian adenocarcinoma. All animal studies were approved by the Institutional Animal Care and Use Committee of Memorial Sloan Kettering Cancer Center. The peritoneal cavity of the animals is surgically exposed, washed, and scanned with a Raman microphotospectrometer. Subsequently, the Raman signatures of the two nanoprobes are decoupled using a Classical Least Squares fitting algorithm, and their respective scores divided to provide a ratiometric signal of folate-targeted over untargeted probes. In this way, microscopic metastases are visualized with high specificity. The main benefit of this approach is that the local application into the peritoneal cavity - which can be done conveniently during the surgical procedure - can tag tumors without subjecting the patient to systemic nanoparticle exposure. False positive signals stemming from non-specific binding of the nanoprobes onto visceral surfaces can be eliminated by following a ratiometric approach where targeted and non-targeted nanoprobes with distinct Raman signatures are applied as a mixture. The procedure is currently still limited by the lack of a commercial wide-field Raman imaging camera system, which once available will allow for the application of this technique in the operating theater.

Gold nanorod-encapsulated biodegradable polymeric matrix for combined photothermal and chemo-cancer therapy

PURPOSE

A biocompatible nanocomplex system co-encapsulated with gold nanorods (AuNRs) and doxorubicin (DOX) was investigated for its potentials on the combined photothermal- and chemotherapy.

MATERIALS AND METHODS

Hydrophobic AuNRs were synthesized by the hexadecyltrimethyl-ammonium bromide (CTAB)-mediated seed growth method, and then, they received two-step surface modifications of polyethylene glycol (PEG) and dodecane. The AuNR/DOX/poly(lactic-co-glycolic acid) (PLGA) nanocomplexes were prepared by emulsifying DOX, AuNR, and PLGA into aqueous polyvinyl alcohol solution by sonication. Human serum albumin (HSA) was used to coat the nanocomplexes to afford HSA/AuNR/DOX-PLGA (HADP). Size and surface potential of the HADP nanocomplexes were determined by using a Zetasizer. Cytotoxicity and cellular uptake of the HADP were analyzed by using MTT assay and flow cytometry, respectively. In vitro anticancer effects of the HADP were studied on various cancer cell lines. To assess the therapeutic efficacy, CT26 tumor-bearing mice were intravenously administered with HADP nanocomplexes and laser treatments, followed by monitoring of the tumor growth and body weight.

RESULTS

Size and surface potential of the HADP nanocomplexes were 245.8 nm and -8.6 mV, respectively. Strong photothermal effects were verified on the AuNR-loaded PLGA nanoparticles (NPs) in vitro. Rapid and repeated drug release from the HADP nanocomplexes was successfully achieved by near-infrared (NIR) irradiations. HSA significantly promoted cellular uptake of the HADP nanocomplexes to murine colon cancer cells as demonstrated by cell imaging and flow cytometric studies. By combining photothermal and chemotherapy, the HADP nanocomplexes exhibited strong synergistic anticancer effects in vitro and in vivo.

CONCLUSION

An NIR-triggered drug release system by encapsulating hydrophobic AuNR and DOX inside the PLGA NPs has been successfully prepared in this study. The HADP NPs show promising combined photothermal- and chemotherapeutic effects without inducing undesired side effects on a murine colon cancer animal model.

Three-dimensional angiography fused with CT/MRI for multimodal imaging of nanoparticles based on Ba4Yb3F17:Lu3+,Gd3+

Designing nanosized multi-modality contrast agents for high-resolution imaging is challenging since most agents are only useful for single-mode imaging. In this work, we successfully synthesized biocompatible polyethylene glycol (PEG-) and l-glutamine (GLN-) modified Ba4Yb3F17:Lu3+,Gd3+ nanoparticles (LNPs@PEG@GLN) that can be employed as a multi-modality contrast agent. Fluorescence dye-modified LNPs@PEG@GLN nanoparticles can be used for computed tomography (CT), magnetic resonance imaging (MRI), and fluorescence imaging (FI). They display high X-ray absorption, outstanding T2-weighted imaging capability, and good fluorescence uptake. Furthermore, LNPs@PEG@GLN enhances contrast efficiencies for different imaging modalities in vivo. Interestingly, LNPs@PEG@GLN is a promising agent for CT angiography. These nanoparticles could be a promising contrast agent for multi-modality imaging and diagnosing vascular diseases.