Benefits of nanoencapsulation for the hypercin-mediated photodetection of ovarian micrometastases

Current development of theragnostic nanoparticles for women's cancer treatment

In the biomedical industry, nanoparticles (NPs-exclusively small particles with size ranging from 1-100 nanometres) are recently employed as powerful tools due to their huge potential in sophisticated and enhanced cancer theragnostic (i.e. therapeutics and diagnostics). Cancer is a life-threatening disease caused by carcinogenic agents and mutation in cells, leading to uncontrolled cell growth and harming the body's normal functioning while affecting several factors like low levels of reactive oxygen species, hyperactive antiapoptotic mRNA expression, reduced proapoptotic mRNA expression, damaged DNA repair, and so on. NPs are extensively used in early cancer diagnosis and are functionalized to target receptors overexpressing cancer cells for effective cancer treatment. This review focuses explicitly on how NPs alone and combined with imaging techniques and advanced treatment techniques have been researched against 'women's cancer' such as breast, ovarian, and cervical cancer which are substantially occurring in women. NPs, in combination with numerous imaging techniques (like PET, SPECT, MRI, etc) have been widely explored for cancer imaging and understanding tumor characteristics. Moreover, NPs in combination with various advanced cancer therapeutics (like magnetic hyperthermia, pH responsiveness, photothermal therapy, etc), have been stated to be more targeted and effective therapeutic strategies with negligible side effects. Furthermore, this review will further help to improve treatment outcomes and patient quality of life based on the theragnostic application-based studies of NPs in women's cancer treatment.

The Application of Nanoparticle-Based Imaging and Phototherapy for Female Reproductive Organs Diseases

Various female reproductive disorders affect millions of women worldwide and bring many troubles to women's daily life. Let alone, gynecological cancer (such as ovarian cancer and cervical cancer) is a severe threat to most women's lives. Endometriosis, pelvic inflammatory disease, and other chronic diseases-induced pain have significantly harmed women's physical and mental health. Despite recent advances in the female reproductive field, the existing challenges are still enormous such as personalization of disease, difficulty in diagnosing early cancers, antibiotic resistance in infectious diseases, etc. To confront such challenges, nanoparticle-based imaging tools and phototherapies that offer minimally invasive detection and treatment of reproductive tract-associated pathologies are indispensable and innovative. Of late, several clinical trials have also been conducted using nanoparticles for the early detection of female reproductive tract infections and cancers, targeted drug delivery, and cellular therapeutics. However, these nanoparticle trials are still nascent due to the body's delicate and complex female reproductive system. The present review comprehensively focuses on emerging nanoparticle-based imaging and phototherapies applications, which hold enormous promise for improved early diagnosis and effective treatments of various female reproductive organ diseases.

Nanoformulations - Insights Towards Characterization Techniques

BACKGROUND

Drug-loaded novel nanoformulations are gaining importance due to their versatile properties compared to conventional pharmaceutical formulations. Nanomaterials, apart from their multifactorial benefits, have a wider scope in the prevention, treatment, and diagnosis of cancer. Understanding the chemistry of drug-loaded nano-formulations to elicit its behaviour both at molecular and systemic levels is critical in the present scenario. Drug-loaded nanoformulations are controlled by their size, shape, surface chemistry, and release behavior. The major pharmaceutical drug loaded nanocarriers reported for anticancer drug delivery for the treatment of various forms of cancers such as lung cancer, liver cancer, breast cancer, colon cancer, etc include nanoparticles, nanospheres, nanodispersions, nanocapsules, nanomicelles, cubosomes, nanoemulsions, liposomes and niosomes. The major objectives in designing anticancer drug-loaded nanoformulations are to manage the particle size/morphology correlating with the drug release to fulfil the specific objectives. Hence, nano characterizations are very critical both at in vitro and in vivo levels.

OBJECTIVE

The main objective of this review paper is to summarise the major characterization techniques used for the characterization of drug-loaded nanoformulations. Even though information on characterization techniques of various nano-formulations is available in the literature, it is scattered. The proposed review will provide a comprehensive understanding of nanocharacterization techniques.

CONCLUSION

To conclude, the proposed review will provide insights towards the different nano characterization techniques along with their recent updates, such as particle size, zeta potential, entrapment efficiency, in vitro release studies (chromatographic HPLC, HPTLC, and LC-MS/MS analysis), EPR analysis, X-ray diffraction analysis, thermal analysis, rheometric, morphological analysis etc. Additionally, the challenges encountered by the nano characterization techniques will also be discussed.

Hypericin photodynamic activity in DPPC liposomes - part II: stability and application in melanoma B16-F10 cancer cells

Hypericin (Hyp) is considered a promising photosensitizer for Photodynamic Therapy (PDT), due to its high hydrophobicity, affinity for cell membranes, low toxicity and high photooxidation activity. In this study, Hyp photophysical properties and photodynamic activity against melanoma B16-F10 cells were optimized using DPPC liposomes (1,2-dipalmitoyl-sn-glycero-3-phosphocholine) as a drug delivery system. This nanoparticle is used as a cell membrane biomimetic model and solubilizes hydrophobic drugs. Hyp oxygen singlet lifetime (τ) in DPPC was approximately two-fold larger than that in P-123 micelles (Pluronic™ surfactants), reflecting a more hydrophobic environment provided by the DPPC liposome. On the other hand, singlet oxygen quantum yield values (Φ_Δ¹O₂) in DPPC and P-123 were similar; Hyp molecules were preserved as monomers. The Hyp/DPPC liposome aqueous dispersion was stable during fluorescence emission and the liposome diameter remained stable for at least five days at 30 °C. However, the liposomes collapsed after the lyophilization/rehydration process, which was resolved by adding the lyoprotectant Trehalose to the liposome dispersion before lyophilization. Cell viability of the Hyp/DPPC formulation was assessed against healthy HaCat cells and high-metastatic melanoma B16-F10 cells. Hyp incorporated into the DPPC carrier presented a higher selectivity index than the Hyp sample previously solubilized in ethanol under the illumination effect. Moreover, the IC₅₀ was lower for Hyp in DPPC than for Hyp pre-solubilized in ethanol. These results indicate the potential of the formulation of Hyp/DPPC for future biomedical applications in PDT treatment.

Copolymeric micelles as efficient inert nanocarrier for hypericin in the photodynamic inactivation of Candida species

Aim: To evaluate the efficacy of photodynamic inactivation (PDI) mediated by hypericin encapsulated in P-123 copolymeric micelles (P123-Hyp) alone and in combination with fluconazole (FLU) against planktonic cells and biofilm formation of Candida species Materials & methods: PDI was performed using P123-Hyp and an LED device with irradiance of 3.0 mW/cm2 . Results: Most of isolates (70%) were completely inhibited with concentrations up to 2.0 μmol/l of HYP and light fluence of 16.2 J/cm2. FLU-resistant strains had synergic effect with P123-HYP-PDI and FLU. The biofilm formation was inhibited in all species, in additional the changes in Candida morphology observed by scanning electron microscopy. Conclusion: P123-Hyp-PDI is a promising option to treat fungal infections and medical devices to prevent biofilm formation and fungal spread.

Development of copolymeric nanoparticles of hypocrellin B: Enhanced phototoxic effect and ocular distribution

In the present work, we have developed a photosensitizer hypocrellin B (HB) and nano silver loaded PLGA-TPGS nanoparticles with improved singlet oxygen production for enhanced photodynamic effect for the efficient treatment of age related macular degeneration. Random copolymer (PLGA-TPGS) synthesized by ring opening and bulk polymerization was characterized by IR, ¹H NMR and TGA analysis. HBS-CP-NPs prepared by nanoprecipitation techniques were spherical shaped 89.6-753.6nm size particles with negative zeta potential. The average encapsulation efficiency was 84.06±11.43% and HB release from the HBS-CP-NPs was found to be biphasic with a slow release of 1.41% in the first 8h and 48.91% during 3days as measured by RP-HPLC. DSC thermograms indicate that HB was dispersed as amorphous form in HBS-CP-NPs. The ROS generation level of HBS-CP-NPs was significantly higher than that of HB/HB-CP-NPs. The production of ¹O₂ of HBS-CP-NPs has been assessed using EPR spectrometer. The ¹O₂ generating efficiency follows the order of nano silver>HB-CP-NPs>HBS-CP-NPs>pure HB drug solution. The superior phototoxic effect of HBS-CP-NPs (85.5% at 50μM) was attained at 2h irradiation in A549 cells. Significant anti angiogenic effect of HBS-CP-NPs was observed in treated CAM embryos. Following intravenous injection of HBS-CP-NPs to rabbits, the maximum amount of HB was found in retina (3h), iris (9h), aqueous humour (9h) and vitreous humour (9h).

Hypocrellin B and nano silver loaded polymeric nanoparticles: Enhanced generation of singlet oxygen for improved photodynamic therapy

A nanoparticulate photodynamic approach was employed with an objective to achieve enhanced production of singlet oxygen (¹O₂), for the management of posterior segment eye diseases like age related macular degeneration. The hypocrellin B (HB) loaded poly lactide-co-glycolide nanoparticle formulations were incorporated with nano silver (HBS-NPs). The optimized HBS-NPs contained 2.60±0.06mg/mL of HB and showed (i) 135.6 to 828.2nm size range, and (ii) negative zeta potential with a narrow polydispersity index. The DSC thermograms suggested the amorphous nature of HB inside the HBS-NPs. With the average encapsulation efficiency of 92.9±1.79%, the drug release from the HBS-NPs followed a biphasic pattern with an initial burst of 3.50% during first 8h followed by a sustained release of 47.82% within 3days. The interaction between nano silver and HB as assessed by the increase in spectral intensity of Raman spectrum demonstrates that HB may be attached over the nano silver. Generation of reactive oxygen species (ROS) by HBS-NPs was significantly higher than that of HB/HB-NPs. The singlet oxygen generating efficiency assessed using EPR spectrometer follows the order of nano silver>HB-NPs>pure HB drug solution>HBS-NPs. The HBS-NPs had a concentration and time dependent phototoxicity on A549 (human adeno lung carcinoma) cells in the presence of light providing a superior phototoxic effect (82.2% at 50μM) at 2h irradiation. The CAM treated with HBS-NPs showed a significant anti-angiogenic effect compared to a blank formulation. In vivo biodistribution studies revealed that intravenous administration of HBS-NPs lead into significant exposure to the posterior segment of the eye. This proof of principle study demonstrates that HB based nanoparticles may be a valuable new tool for application in ocular photodynamic therapy for the treatment of AMD in future.

Development of nanoscale approaches for ovarian cancer therapeutics and diagnostics

Ovarian cancer is the deadliest of all gynecological cancers and the fifth leading cause of death due to cancer in women. This is largely due to late-stage diagnosis, poor prognosis related to advanced-stage disease, and the high recurrence rate associated with development of chemoresistance. Survival statistics have not improved significantly over the last three decades, highlighting the fact that improved therapeutic strategies and early detection require substantial improvements. Here, we review and highlight nanotechnology-based approaches that seek to address this need. The success of Doxil, a PEGylated liposomal nanoencapsulation of doxorubicin, which was approved by the FDA for use on recurrent ovarian cancer, has paved the way for the current wave of nanoparticle formulations in drug discovery and clinical trials. We discuss and summarize new nanoformulations that are currently moving into clinical trials and highlight novel nanotherapeutic strategies that have shown promising results in preclinical in vivo studies. Further, the potential for nanomaterials in diagnostic imaging techniques and the ability to leverage nanotechnology for early detection of ovarian cancer are also discussed.

Hypericin-loaded lipid nanocapsules for photodynamic cancer therapy in vitro

Hypericin (Hy), a naturally occurring photosensitizer (PS), is extracted from Hypericum perforatum plants, commonly known as St. John's wort. The discovery of the in vitro and in vivo photodynamic activities of hypericin as a photosensitizer generated great interest, mainly to induce a very potent antitumoral effect. However, this compound belongs to the family of naphthodianthrones which are known to be poorly soluble in physiological solutions and produce non-fluorescent aggregates (A. Wirz et al., Pharmazie, 2002, 57, 543; A. Kubin et al., Pharmazie, 2008, 63, 263). These phenomena can reduce its efficiency as a photosensitizer for the clinical application. In the present contribution, we have prepared, characterized, and studied the photochemical properties of Hy-loaded lipid nanocapsule (LNC) formulations. The amount of singlet oxygen ((1)O2) generated was measured by the use of p-nitroso-dimethylaniline (RNO) as a selective scavenger under visible light irradiation. Our results showed that Hy-loaded LNCs suppressed aggregation of Hy in aqueous media, increased its apparent solubility, and enhanced the production of singlet oxygen in comparison with free drug. Indeed, encapsulation of Hy in LNCs led to an increase of (1)O2 quantum yield to 0.29-0.44, as compared to 0.02 reported for free Hy in water. Additionally, we studied the photodynamic activity of Hy-loaded LNCs on human cervical carcinoma (HeLa) and Human Embryonic Kidney (HEK) cells. The cell viability decreased radically to 10-20% at 1 μM, reflecting Hy-loaded LNC25 phototoxicity.

Gold nanoparticle-enhanced and size-dependent generation of reactive oxygen species from protoporphyrin IX

Photosensitizer, protoporphyrin IX (PpIX), was conjugated with Au nanoparticles (Au NPs) of 19, 66, and 106 nm diameter to study the size-dependent enhancement of reactive oxygen species (ROS) formation enabled by Au NPs. The ROS enhancement ratio is determined to be 1:2.56:4.72 in order of increasing Au NP size, in general agreement with theoretically calculated field enhancement to the fourth power. The convergence of the experimental and simulated results suggests that Au NP-enhanced and size-dependent ROS formation can be attributed directly to the localized electromagnetic field as a result of surface plasmonic resonance of Au NPs under light irradiation. In vitro study on the ROS formation enabled by PpIX-conjugated Au NPs in human breast cancer cells (MDA-MB-231) revealed the similar size-dependent enhancement of intracellular ROS formation, while the enhancement greatly depended on cellular uptake of Au NPs. Cellular photodynamic therapy revealed that cell destruction significantly increased in the presence of Au NPs. Compared to the untreated control (0% destruction), 22.6% cell destruction was seen in the PpIX alone group and more than 50% cell destruction was obtained for all PpIX-conjugated Au NPs. The 66 nm Au NPs yielded the highest cell destruction, consistent with the highest cellular uptake and highest ROS formation. Clearly, the complex cellular environment, size-dependent cellular uptake of Au NPs, and ROS generations are vital contributors to the overall cellular PDT efficacy.

Targeted Therapy of Cancer Using Photodynamic Therapy in Combination with Multi-faceted Anti-Tumor Modalities

Photodynamic therapy (PDT) has emerged as one of the important therapeutic options in the management of cancer and other diseases. PDT involves a tumor-localized photosensitizer (PS), which when appropriately illuminated by visible light converts oxygen into cytotoxic reactive oxygen species (ROS), that attack key structural entities within the targeted cells, ultimately resulting in necrosis or apoptosis. Though PDT is a selective modality, it can be further enhanced by combining other targeted therapeutic strategies that include the use of synthetic peptides and nanoparticles for selective delivery of photosensitizers. Another potentially promising strategy is the application of targeted therapeutics that exploit a myriad of critical pathways involved in tumorigenesis and metastasis. Vascular disrupting agents that eradicate tumor vasculature during PDT and anti-angiogenic agents that targets specific molecular pathways and prevent the formation of new blood vessels are novel therapeutic approaches that have been shown to improve treatment outcome. In addition to the well-documented mechanisms of direct cell killing and damage to the tumor vasculature, PDT can also activate the body's immune response against tumors. Numerous pre-clinical studies and clinical observations have demonstrated the immuno-stimulatory capability of PDT. Herein, we aim to integrate the most important findings with regard to the combination of PDT and other novel targeted therapy approaches, detailing its potential in cancer photomedicine.