phytochlorin and Mouth-Neoplasms

Hypoxia is an important pathological hallmark of the tumor microenvironment, associated with metabolic alterations, cell proliferation, aggressiveness, metastasis, and therapy resistance in cancers. Hypoxia impedes the outcome of photodynamic therapy (PDT), which is largely dependent on molecular oxygen to generate cytotoxic

Topics: Animals; Antineoplastic Agents; Carcinoma, Squamous Cell; Cell Line, Tumor; Chlorophyllides; Head and Neck Neoplasms; Hypoxia; Mice; Mouth Neoplasms; Nanomedicine; Nanoparticles; Oxygen; Photochemotherapy; Photosensitizing Agents; Platinum; Porphyrins; Squamous Cell Carcinoma of Head and Neck

Activation of the epithelial to mesenchymal transition (EMT) in photodynamic therapy (PDT) can lead to the recurrence and progression of tumors. To enhance the effects of PDT, it is essential to inhibit the Wnt/β-catenin signaling pathway involved in EMT progression. Herein, we used polyethylene glycol-polyethyleneimine-chlorin e6 (PEG-PEI-Ce6) nanoparticles to efficiently deliver Wnt-1 small interfering RNA (siRNA) to the cytoplasm of KB cells (oral squamous cell carcinoma) that were subjected to PDT. Wnt-1 siRNA effectively inhibited the Wnt/β-catenin signaling pathway, reducing the expression of Wnt-1, β-catenin and vimentin that are crucial to the EMT. Combined with Wnt-1 siRNA, PEG-PEI-Ce6 nanoparticle mediated PDT inhibited cell growth and enhanced the cancer cell killing effect remarkably. Our results show the promise of combination therapy of PEG-PEI-Ce6 nanoparticles for delivery of Wnt-1 siRNA along with PDT in the treatment of oral cancer.

Topics: Cell Line, Tumor; Chlorophyllides; Epithelial-Mesenchymal Transition; Humans; Mouth Neoplasms; Nanoparticles; Photochemotherapy; Polyethylene Glycols; Polyethyleneimine; Porphyrins; RNA, Small Interfering; RNAi Therapeutics; Wnt1 Protein

Overexpression of epidermal growth factor receptor (EGFR) is observed in oral squamous cell carcinoma (OSCC) and is associated with increased proliferation, metastasis and therapeutic resistance. We aim to develop a novel drug delivery system comprised of a photosensitizer Chlorin e6 (Ce6) that is encapsulated in a viral envelope and tagged with anti-EGFR antibody to target OSCC.. Ce6 was encapsulated in both virosomes (Ce6-Vir) and virosomes tagged with anti-EGFR antibody (Ce6-Vir-EGFR'). In vitro studies were conducted to assess the cellular uptake and bioavailability of the photosensitizer in OSCC cells. Ce6 alone or in constructs was then administered in a hamster cheek pouch model and fluorescence imaging and spectroscopy was performed.. In vitro results showed that the uptake of Ce6-Vir-EGFR' was lower than that for Ce6-Vir and Ce6 possibly due to its large size. Nevertheless, in vivo results showed significant tumor specificity of Ce6-Vir-EGFR' compared to Ce6. The tumor to normal mucosa ratio showed that Ce6-Vir-EGFR' can successfully target OSCC lesions and therefore shows potential for use in fluorescence diagnosis of OSCC.. Both the virosome-Ce6 constructs were internalized by OSCC cells and successfully used for fluorescence imaging. Tagging with anti-EGFR antibody further improved the targeting ability toward OSCC.

Topics: 9,10-Dimethyl-1,2-benzanthracene; Animals; Antibodies, Monoclonal; Carcinogens; Cell Line, Tumor; Cell Survival; Cheek; Chlorophyllides; Cricetinae; ErbB Receptors; Fluorescence; Humans; Male; Microscopy, Fluorescence; Mouth Mucosa; Mouth Neoplasms; Optical Imaging; Photosensitizing Agents; Porphyrins; Virosomes

The activity of chlorin e6 (Ce6) in photodynamic therapy of cancers is significantly reduced by its propensity to form aggregates. It was postulated that disaggregation of Ce6 could be achieved with the use of hydroxypropyl-beta-cyclodextrin (HP-β-CD) through solubility enhancement.. An initial phase solubility study of Ce6 was conducted with various concentrations of HP-β-CD at three different pH conditions, i.e. pH 3, pH 5 and pH 7. Solubility-induced disaggregation of Ce6 was illustrated by fluorescence spectroscopy and singlet oxygen generation studies. Interaction between Ce6 and HP-β-CD was further demonstrated by solid-state characterization techniques. Inclusion complex formulations were tested for improved efficacy on squamous cancer cell lines.. Increase in Ce6 solubility was observed, especially at pH 7, indicating the formation of inclusion complex between Ce6 and HP-β-CD. This resulted in disaggregation of Ce6 aggregates illustrated by fluorescence spectroscopy. The mode of binding was predominated by H-bonding supported by temperature-dependent binding studies and molecular simulation work. The inclusion complex demonstrated improved photodynamic efficacy through enhanced singlet oxygen generation and phototoxicity on human oral squamous carcinoma cells.. pH-dependent complexation between Ce6- and HP-β-CD-induced disaggregation of Ce6 aggregates and the resultant formulations facilitated improved PDT efficacy on tested cancer cell lines.

Topics: 2-Hydroxypropyl-beta-cyclodextrin; beta-Cyclodextrins; Calorimetry, Differential Scanning; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Survival; Chlorophyllides; Crystallography, X-Ray; Dose-Response Relationship, Drug; Drug Compounding; Head and Neck Neoplasms; Humans; Hydrogen-Ion Concentration; Models, Molecular; Mouth Neoplasms; Photochemotherapy; Photosensitizing Agents; Porphyrins; Powder Diffraction; Singlet Oxygen; Solubility; Spectrometry, Fluorescence; Spectroscopy, Fourier Transform Infrared; Squamous Cell Carcinoma of Head and Neck; Thermodynamics; Time Factors

Despite the advantages of using photodynamic therapy (PDT) for the treatment of head and neck tumors, it can only be used to treat early stage flat lesions due to the limited tissue penetration ability of the visible light. Here, we developed near-infrared (NIR) excitable upconversion nanoparticle (UCN) based PDT agent that can specifically target epithelial growth factor receptor (EGFR) overexpressing oral cancer cells, in a bid to widen the application of PDT against thick and solid advanced or recurrent head and neck cancers. In vivo studies using the synthesized anti-EGFR-PEG-TiO2-UCNs following systemic administration displayed no major sub-acute or long term toxic effects in terms of blood biochemical, hematological or histopathological changes at a concentration of 50 mg/kg. NIR-PDT even in the presence of a 10 mm tissue phantom placed over the xenograft tumor, showed significant delay in tumor growth and improved survival rate compared to conventional chlorin-e6 (Ce6) PDT using 665 nm red light. Our work, one of the longest study till date in terms of safety (120 d), PDT efficacy (35 d) and survival (60 d), demonstrates the usefulness of UCN based PDT technology for targeted treatment of thick and bulky head and neck tumors.

Topics: Animals; Biocompatible Materials; Cell Line, Tumor; Chlorophyllides; Drug Delivery Systems; ErbB Receptors; Female; Humans; Infrared Rays; Mice, Inbred BALB C; Mice, Nude; Mouth Neoplasms; Nanoparticles; Photochemotherapy; Photosensitizing Agents; Porphyrins; Reactive Oxygen Species; Titanium; Xenograft Model Antitumor Assays

Oral squamous cell carcinoma (OSCC) represents 90% of all oral cancers and is characterized with poor prognosis and low survival rate. Epidermal growth factor receptor (EGFR) is highly expressed in oral cancer and is a target for cancer therapy and prevention. In this present work, we evaluate the efficacy of photodynamic therapy (PDT) in combination with an EGFR inhibitor, nimotuzumab in oral cancer cell lines and OSCC xenograft tumor model. PDT is a promising and minimally invasive treatment modality that involves the interaction of a photosensitizer, molecular oxygen and light to destroy tumors. We demonstrated that EGFR inhibitors nimotuzumab and cetuximab exhibits anti-angiogenic properties by inhibiting the migration and invasion of oral cancer cell lines and human endothelial cells. The EGFR inhibitors also significantly reduced tube formation of endothelial cells. Chlorin e6-PDT in combination with nimotuzumab and cetuximab reduced cell proliferation in different oral cancer and endothelial cells. Furthermore, our in vivo studies showed that the combination therapy of PDT and nimotuzumab synergistically delayed tumor growth when compared with control and PDT treated tumors. Downregulation of EGFR, Ki-67 and CD31 was observed in the tumors treated with combination therapy. Analysis of the liver and kidney function markers showed no treatment related toxicity. In conclusion, PDT outcome of oral cancer can be improved when combined with EGFR inhibitor nimotuzumab.

Topics: Animals; Antibodies, Monoclonal, Humanized; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Proliferation; Chlorophyllides; Combined Modality Therapy; Drug Synergism; ErbB Receptors; Head and Neck Neoplasms; Human Umbilical Vein Endothelial Cells; Humans; Mice; Mice, Inbred BALB C; Mice, Nude; Mouth Neoplasms; Photochemotherapy; Porphyrins; Radiation-Sensitizing Agents; Random Allocation; Squamous Cell Carcinoma of Head and Neck; Xenograft Model Antitumor Assays

Quantification of fluorescence in vivo is complicated by the influence of tissue optical properties on the collected fluorescence signal. When tissue optical properties in the measurement volume are quantified, one can obtain the intrinsic fluorescence, which equals the product of fluorophore absorption coefficient and quantum yield. We applied this method to in vivo single-fiber fluorescence spectroscopy measurements on mouse tongue, skin, liver, and oral squamous cell carcinoma, where we detected intrinsic fluorescence spectra of the photosensitizers chlorin e6 and Bremachlorin at t=[3,4.5,6,24,48]  h incubation time. We observed a tissue-dependent maximum of 35% variation in the total correction factor over the visible wavelength range. Significant differences in spectral shape over time between sensitizers were observed. Although the wavelength position of the fluorescence intensity maximum for ce6 shifted to the red, Bremachlorin showed a blue shift. Furthermore, the Bremachlorin peak appeared to be broader than the ce6 fluorescence peak. Intrinsic fluorescence intensity, which can be related to photosensitizer concentration, was decreasing for all time points but showed significantly more Bremachlorin present compared to ce6 at long incubation times. Results from this study can be used to define an optimal treatment protocol for Bremachlorin-based photodynamic therapy.

Topics: Animals; Carcinoma, Squamous Cell; Chlorophyll; Chlorophyllides; Female; Fluorescence; Green Fluorescent Proteins; Liver; Mice; Mice, Inbred BALB C; Mice, Nude; Microscopy, Fluorescence; Mouth Neoplasms; Normal Distribution; Optics and Photonics; Photochemotherapy; Photosensitizing Agents; Porphyrins; Skin; Spectrometry, Fluorescence; Spectrophotometry; Tongue

Immunophotodiagnosis uses a fluorescence-labeled monoclonal antibody (MAb) that recognizes a tumor-associated antigen to image the fluorescence emitted from the fluorophore-bound MAb that has localized in the tissue. It may be used to diagnose malignant or precancerous lesions, to delineate the margins for tumor resection, or as a feedback mechanism to assess response to treatment. In oral precancer, the epidermal growth factor receptor (EGFR) is overexpressed and could be used as a marker for early detection or as a target for therapy. The goal of this study was to test an anti-EGFR MAb (C225) coupled to either the near-infrared fluorescent dye N,N'-di-carboxypentyl-indodicarbocyanine-5,5'-disulfonic acid for detection or a photochemically active dye (chlorin(e6)) for therapy of early premalignancy in the hamster cheek pouch carcinogenesis model. Fluorescence levels in the carcinogen-treated tissue correlated with the histological stage of the lesions when the C225-N,N'-di-carboxypentyl-indodicarbocyanine-5,5'-disulfonic acid conjugate was used but did not do so with the irrelevant conjugates. Discrete areas of clinically normal mucosa with high fluorescence (hot spots) were subsequently shown by histology to contain dysplastic areas. The best contrast between normal and carcinogen-treated cheek pouches was found at 4-8 days after injection. To test the potential of immunophotodiagnosis as a feedback modality for therapeutic intervention, experiments were conducted with the same MAb conjugated to chlorin(e6) followed by illumination to reduce expression of the EGFR by a photodynamic effect. Subsequent immunophotodiagnosis showed that this treatment led to a significant reduction in fluorescence in the carcinogen-treated cheek pouch compared with nonilluminated areas. This difference between illuminated and dark areas was not seen in the normal cheek pouch. Taken together, the results demonstrate the potential for development of immunophotodiagnosis as a diagnostic tool and as a method of monitoring response to therapy and that the EGFR may be an appropriate target in head and neck cancer.

Topics: Animals; Antibodies, Monoclonal; Carcinoma, Squamous Cell; Chlorophyllides; Cricetinae; ErbB Receptors; Fluorescent Dyes; Humans; Immunoconjugates; Immunotherapy; Male; Mesocricetus; Mouth Neoplasms; Phototherapy; Pilot Projects; Porphyrins; Precancerous Conditions; Radiation-Sensitizing Agents; Tumor Cells, Cultured