Photodynamic treatment outcomes of potentially-malignant lesions and malignancies of the head and neck region: A systematic review

A complete course of photodynamic therapy reduced the risk of malignant transformation of oral leukoplakia

BACKGROUND

Photodynamic therapy (PDT) has shown good short-term efficacy in the treatment of oral leukoplakia (OLK). However, the malignant transformation of OLK was seldom evaluated in most PDT studies. Therefore, this study evaluated the effect of PDT on the risk of malignant transformation of OLK.

METHODS

Kaplan-Meier survival analysis, COX regression, and sensitivity analysis were used to evaluate the effects of PDT on the risk of malignant transformation of OLK. Subgroup analyses were performed to explore the role of PDT in OLK patients with different clinical characteristics.

RESULTS

OLK patients with older age (HR=1.032, P = 0.018) and non-homogeneous lesion (HR=2.104, P = 0.044) had higher risk of malignant transformation. Patients who had finished a complete course of PDT (HR=0.305, P = 0.006) had a significant lower risk of malignant transformation, while those who hadn't finished a complete course of PDT (HR=0.692, P = 0.352) cannot be considered to have such a protective effect. In the subgroup analyses, complete PDT course showed a significant protective effect on malignant transformation of OLK in patients with female sex, no smoking or drinking habits, non-homogeneous lesions, lesions on oral mucosa outside the dangerous region, and any grade of epithelial dysplasia.

CONCLUSIONS

A complete course of PDT could significantly reduce the risk of malignant transformation of OLK, especially in those patients with risk factors of malignant transformation.

Effect of 5-Aminolevulinic Acid (5-ALA) in "ALADENT" Gel Formulation and Photodynamic Therapy (PDT) against Human Oral and Pancreatic Cancers

Oral squamous-cell and pancreatic carcinomas are aggressive cancers with a poor outcome. Photodynamic therapy (PDT) consists of the use of photosensitizer-induced cell and tissue damage that is activated by exposure to visible light. PDT selectively acts on cancer cells, which have an accumulation of photosensitizer superior to that of the normal surrounding tissues. 5-aminolevulinic acid (5-ALA) induces the production of protoporphyrin IX (PpIX), an endogenous photosensitizer activated in PDT. This study aimed to test the effect of a new gel containing 5% v/v 5-ALA (ALAD-PDT) on human oral CAL-27 and pancreatic CAPAN-2 cancer cell lines. The cell lines were incubated in low concentrations of ALAD-PDT (0.05%, 0.10%, 0.20%, 0.40%, 0.75%, 1.0%) for 4 h or 8 h, and then irradiated for 7 min with 630 nm RED light. The cytotoxic effects of ALAD-PDT were measured using the MTS assay. Apoptosis, cell cycle, and ROS assays were performed using flow cytometry. PpIX accumulation was measured using a spectrofluorometer after 10 min and 24 and 48 h of treatment. The viability was extremely reduced at all concentrations, at 4 h for CAPAN-2 and at 8 h for CAL-27. ALAD-PDT induced marked apoptosis rates in both oral and pancreatic cancer cells. Elevated ROS production and appreciable levels of PpIX were detected in both cell lines. The use of ALA-PDT as a topical or intralesional therapy would permit the use of very low doses to achieve effective results and minimize side effects. ALAD-PDT has the potential to play a significant role in complex oral and pancreatic anticancer therapies.

Photodynamic therapy in treatment of squamous cell carcinoma of oral cavity with chlorine e6 photosensitizer with long-term follow up

Photodynamic therapy is an effective method for treating superficial forms of malignant neoplasms, characterized by a minimal risk of damage to normal tissues. In this study, we presented our experience of treating cancer of the oral mucosa using photodynamic therapy, and analyzed the immediate and long-term results of treatment. 38 patients with squamous cell carcinoma of oral cavity mucosa, with a depth of invasion no more than 7 mm, were included in the study. All patients underwent photodynamic therapy with chlorine e6 based photosensitizer. Photosensitizers were administered intravenously 3 hours before irradiation, at a dosage of 1 mg/kg of the patient’s weight. Photodynamic therapy was performed with the following parameters: P – 1.0 W, Ps – 0.31 W/cm2, E – 300 J/cm2. The area of one irradiation field ranged 1.0-2.0 cm2. Treatment effect was evaluated by RECIST 1.1. Overall survival, cancer-specific survival, and disease-free survival were calculated using Kaplan-Meier curves. Evaluation of adverse events was made by .TCAE 5.0 criteria. At 35 (92.1%) out of 38 cases, complete regression was observed after photodynamic therapy. Among them in 3 out of 35 patients relapse was diagnosed in 11.5 to 43.2 months. The total number of patients who didn’t respond to treatment was 6 (15.8%). Follow-up period was 4.2-87.3 months. (mean 42.9). 34 (89.5%) out of 38 patients are alive, 1 (2.6%) died from progression, and three died from other causes. The 5-year overall survival rate was 82.1%, cancer-specific survival rate was 97.0%, and disease-free survival rate was 81.1%. Among the factors significantly (p < 0.05) influencing relapse-free survival: depth of invasion < 5 mm (p – 0.013) and the presence of leukoplakia (p – 0.007). When assessing cancer-specific survival, factors worsening the prognosis were: age >70 years (p – 0.034) and the presence of leukoplakia (p – 0.007). Photodynamic therapy is an alternative treatment method of oral cancer superficial lesions, in case of proper assessment of primary lesion and in case of possibility of full irradiation of the tumor. Moreover, after using photodynamic therapy, the underlying connective-muscular structures are preserved, which promotes rapid healing with minimal scarring, the functions of the affected organ remain intact, and cosmetic defects do not form.

Comparative response to PDT with methyl-aminolevulinate and temoporfin in cutaneous and oral squamous cell carcinoma cells

Cutaneous and Head and Neck squamous cell carcinoma (CSCC, HNSCC) are among the most prevalent cancers. Both types of cancer can be treated with photodynamic therapy (PDT) by using the photosensitizer Temoporfin in HNSCC and the prodrug methyl-aminolevulinate (MAL) in CSCC. However, PDT is not always effective. Therefore, it is mandatory to correctly approach the therapy according to the characteristics of the tumour cells. For this reason, we have used cell lines of CSCC (A431 and SCC13) and HNSCC (HN5 and SCC9). The results obtained indicated that the better response to MAL-PDT was related to its localization in the plasma membrane (A431 and HN5 cells). However, with Temoporfin all cell lines showed lysosome localization, even the most sensitive ones (HN5). The expression of mesenchymal markers and migratory capacity was greater in HNSCC lines compared to CSCC, but no correlation with PDT response was observed. The translocation to the nucleus of β-catenin and GSK3β and the activation of NF-κβ is related to the poor response to PDT in the HNSCC lines. Therefore, we propose that intracellular localization of GSK3β could be a good marker of response to PDT in HNSCC. Although the molecular mechanism of response to PDT needs further elucidation, this work shows that the most MAL-resistant line of CSCC is more sensitive to Temoporfin.

Effect of Hypericin-Mediated Photodynamic Therapy on the Secretion of Soluble TNF Receptors by Oral Cancer Cells

Squamous cell carcinoma is the most common cancer of the head and neck region. In addition to the classic surgical treatment method, alternative therapy methods are sought. One such method is photodynamic therapy (PDT). In addition to the direct cytotoxic effect, it is essential to determine the effect of PDT on persistent tumor cells. The study used the SCC-25 oral squamous cell carcinoma (OSCC) cell line and the HGF-1 healthy gingival fibroblast line. A compound of natural origin-hypericin (HY)-was used as a photosensitizer (PS) at concentrations of 0-1 µM. After two hours of incubation with the PS, the cells were irradiated with light doses of 0-20 J/cm². The 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) test was used to determine sublethal doses of PDT. Cell supernatants subjected to sublethal PDT were assessed for soluble tumor necrosis alpha receptors (sTNF-R1, sTNF-R2). The phototoxic effect was observed starting with a light dose of 5 J/cm² and amplified with the increase in HY concentration and light dose. A statistically significant increase in sTNF-R1 secretion by SCC-25 cells was demonstrated after the PDT with 0.5 µM HY and irradiation with 2 J/cm² (sTNF-R1 concentration = 189.19 pg/mL ± 2.60) compared to the control without HY and irradiated with the same dose of light (sTNF-R1 concentration = 108.94 pg/mL ± 0.99). The baseline production of sTNF-R1 was lower for HGF-1 than for SCC-25, and secretion was not affected by the PDT. The PDT had no effect on the sTNF-R2 production in the SCC-25 or HGF-1 lines.

Developmental synergism in the management of oral potentially malignant disorders

Oral potentially malignant disorders (OPMDs) are associated with an increased risk of occurrence of cancers of the oral cavity or lips. The unifying theme of OPMDs is their potential risk for cancer development. Therefore, the primary objective of the management should be to prevent carcinogenesis. Beyond diagnosis, current strategies for the management of OPMDs predominantly include non-surgical and surgical interventions and a "watch-and-see" approach, such as disease monitoring or surveillance, and preventive strategies. Though no optimal clinical treatment has gained universal approval for reducing or preventing malignant development of OPMDs. Therefore, an urgent need exits for improved treatment properties and effective predictive markers for OPMDs treatment. This review aims to outline recent synergism regarding to the management of OPMDs. Developing new technologies and improved application parameters to promote the treatment efficacy and a novel management prescription approach to OPMDs are proposed.

Revisiting the evidence of photodynamic therapy for oral potentially malignant disorders and oral squamous cell carcinoma: an overview of systematic reviews

BACKGROUND

This study summarized the available evidence about the use of photodynamic therapy (PDT) for the management of oral potentially malignant disorders (OPMD) and oral squamous cell carcinoma (OSCC).

METHODS

An overview of systematic reviews was undertaken based on the 2020 PRISMA statement. Electronic searches were performed in five databases. Studies published up to November 2022 were included. Risk of bias was assessed with the AMSTAR 2 tool.

RESULTS

A total of 30 studies enrolling 9,245 individuals with OPMD (n=7,487) or OSCC (n=1,758) met the selection criteria. All studies examined the efficacy and/or safety of PDT. OPMD were investigated individually in 82.8% of the studies, the most common being oral lichen planus and actinic cheilitis. OSCC was addressed separately in 10.3% of the studies, while only 6.9% evaluated both OPMD and OSCC. Fourteen different types of photosensitizers were described. PDT was used according to the following setting parameters: 417-670 nm, 10-500 mW/cm², 1.5-200 J/cm², and 0.5-143 minutes. Regarding OPMD, leukoerythroplakia showed the best response rates, while oral lichen planus presented a partial or no response in nearly 75% of documented cases. A complete response was observed in 85.9% of OSCC cases, while 14.1% had no resolution.

CONCLUSION

Overall, the response to PDT depended on the type of OPMD/OSCC and the parameters used. Although PDT is an emerging candidate for the treatment of OPMD and OSCC, there is heterogeneity of the methodologies used and the clinical data obtained, particularly regarding the follow-up period.

Decorated Au NPs on lignin coated magnetic nanoparticles: Investigation of its catalytic application in the reduction of aromatic nitro compounds and its performance against human lung cancer

In the recent years, bio-functionalized noble metal doped advanced magnetics nanocomposite materials has been materialized as potential featured catalysts in diverse applications. In this connection, we report herein a novel biogenic lignin driven Au nanoparticle supported Fe₃O₄ composite material. The procedure is free from any harsh reducing or stabilizing agent. Morphology and structural features were assessed following different physicochemical methodologies like FT-IR, FE-SEM, TEM, EDS, XRD, VSM and ICP-OES techniques. Thereafter, the [Fe₃O₄/Lignin/Au] material was successfully employed in the efficient reduction of different nitroarenes in aqueous medium. The process was monitored over UV-Vis spectroscopic study. Excellent yields were achieved with a range of diverse functionalized nitroarenes within 10-45 min of reaction. The nanocatalyst was recycled 10 times without any significant loss of catalytic activity. Distinctiveness of the material's activity was validated by comparing the results in the reduction of 4-nitrophenol. Furthermore, the prepared [Fe₃O₄/Lignin/Au] nanocomposite system exhibited outstanding antioxidant and anticancer effects against five lung cancer cell lines, such as, BICR 3, BICR 78, CALU 1, ChaGo-K-1, and A549. Cytotoxicity assay was determined in terms of % cell viability following MTT protocol. The corresponding IC₅₀ values were obtained as 47, 31, 19, 25, and 31 μg/mL respectively.

Multi-Modal Optical Imaging and Combined Phototherapy of Nasopharyngeal Carcinoma Based on a Nanoplatform

Nasopharyngeal carcinoma (NPC) is a common malignant tumor of the head and neck with a high incidence rate worldwide, especially in southern China. Phototheranostics in combination with nanoparticles is an integrated strategy for enabling simultaneous diagnosis, real-time monitoring, and administration of precision therapy for nasopharyngeal carcinoma (NPC). It has shown great potential in the field of cancer diagnosis and treatment owing to its unique noninvasive advantages. Many Chinese and international research teams have applied nano-targeted drugs to optical diagnosis and treatment technology to conduct multimodal imaging and collaborative treatment of NPC, which has become a hot research topic. In this review, we aimed to introduce the recent developments in phototheranostics of NPC based on a nanoplatform. This study aimed to elaborate on the applications of nanoplatform-based optical imaging strategies and treatment modalities, including fluorescence imaging, photoacoustic imaging, Raman spectroscopy imaging, photodynamic therapy, and photothermal therapy. This study is expected to provide a scientific basis for further research and development of NPC diagnosis and treatment.

ROS Pleiotropy in Melanoma and Local Therapy with Physical Modalities

Metabolic energy production naturally generates unwanted products such as reactive oxygen species (ROS), causing oxidative damage. Oxidative damage has been linked to several pathologies, including diabetes, premature aging, neurodegenerative diseases, and cancer. ROS were therefore originally anticipated as an imperative evil, a product of an imperfect system. More recently, however, the role of ROS in signaling and tumor treatment is increasingly acknowledged. This review addresses the main types, sources, and pathways of ROS in melanoma by linking their pleiotropic roles in antioxidant and oxidant regulation, hypoxia, metabolism, and cell death. In addition, the implications of ROS in various physical therapy modalities targeting melanoma, such as radiotherapy, electrochemotherapy, hyperthermia, photodynamic therapy, and medical gas plasma, are also discussed. By including ROS in the main picture of melanoma skin cancer and as an integral part of cancer therapies, a greater understanding of melanoma cell biology is presented, which ultimately may elucidate additional clues on targeting therapy resistance of this most deadly form of skin cancer.

[Progress on photodynamic therapy in oral diseases]

Photodynamic therapy (PDT) has developed rapidly in basic and clinical research, and its therapeutic prospects have received increasing attention. PDT has the advantages of minimally invasive, low toxicity, high selectivity, good reproducibility, protection of appearance and vital organ function, and has become a treatment. With the development of medicine, the field of application of PDT becomes more wildly, and brings a new direction for the treatment of oral diseases. This article reviews the basic principles, treatment elements and research results of PDT in the treatment of oral diseases.

Small Dysplastic Oral Leucoplakia in a Smoking Woman: a Case Report

Background

Oral leucoplakia is clinical term used to describe white plaques, and that is part of the group of oral potentially malignant disorders. Leucoplakia may show epithelial dysplasia, mainly in harder smoking patient. This case report discusses a small leucoplakia with dysplasia on the tongue's lateral border in a woman, diagnosed early after a routine clinical consultation.

Methods

A 57-year-old female patient consulted to the Oral Diagnosis and Surgery Service of the State University of Ponta Grossa, Brazil. First, the patient was referred for the extraction of her lower incisors due to periodontal disease. During clinical examination, was identified a sessile white plaque, of small size, and located on the tongue's left lateral border. Thus, the lesion's diagnostic hypothesis was oral leucoplakia due to patient be chronic smoker for 40 years. The incisional biopsy was performed, with the epithelial tissue and part of the connective tissue removed.

Results

The histopathological examination revealed a stratified and keratinized pavement epithelium, with cellular atypia, and presence of hyperchromatism and nuclear pleomorphism. However, the alterations were restricted to the epithelium's basal, characterizing a mild dysplasia. The proposed treatment was surgical removal of the lesion, and the patient was also instructed to quit smoking, as well as she continues to follow-up.

Conclusions

The presented case emphasizes the importance of early diagnosis and the orientation of risk factors to smoking patients, even in small lesions that can clinically appear harmless.

Photodynamic Therapy as an Alternative Therapeutic Tool in Functionally Inoperable Oral and Oropharyngeal Carcinoma: A Single Tertiary Center Retrospective Cohort Analysis

Background: Head and neck cancer is typically treated with surgery, radiotherapy, chemoradiation, or a combination of these treatments. This study aims to retrospectively analyse oncological outcomes, adverse events and toxicity of treatment with temoporfin-mediated photodynamic therapy at a single tertiary referral center. More specifically, in a selected group of patients with otherwise (functionally) inoperable oral or oropharyngeal head and neck squamous cell carcinoma.

Methods: Twenty-six consecutive patients who received photodynamic therapy for oral or oropharyngeal squamous cell carcinoma from January 2002 until July 2019 at the University Hospitals Leuven were included. These were (1) patients with an accessible recurrent or new primary tumor in an extensively treated area of the head and neck, not suitable for standard treatment, or (2) patients that were judged medically unfit to undergo standard treatment modalities.

Results: Complete tumor response immediately after PDT was obtained in 76.9% of cases. During follow-up, a proportion of CR patients did recur, to reach recurrence-free rates at six months, one year and two years of 60.6%, 48.5% and 32.3%. Local control at the PDT treated area was 42.3% with a median recurrence free interval time of 9 months. Recurrence-free interval was statistically more favorable for oropharyngeal squamous cell carcinoma (with or without oral cavity extension) in comparison to oral cavity squamous cell carcinoma alone (p < 0.001). During a median follow-up period of 27 months, we report new tumor activity in 80.8% of patients. Median overall and disease-specific survival time was 31 and 34 months, respectively. Most reported adverse events were pain after treatment and facial edema. At the end of follow-up, swallowing and upper airway functionality were preserved in 76.9 and 95.7% of patients, respectively.

Conclusion: Photodynamic therapy is a valuable treatment option in highly selected patients with oral and/or oropharyngeal (functionally) inoperable head and neck squamous cell carcinoma. Treatment with this alternative modality can induce durable local control in an important fraction of treated patients, with an acceptable toxicity profile.

Topical photodynamic therapy in the treatment of benign oral mucosal lesions: A systematic review

BACKGROUND

The introduction of photodynamic therapy (PDT) in various branches of the dental field such as endodontics, implantology, periodontology, and restorative dentistry and oral medicine has become useful in recent decades. This systematic review presents an overview of the literature to evaluate the usefulness of topical PDT for the treatment of benign oral soft tissue lesions and to identify limitations in prior studies to improve PDT applications.

METHODS

We performed a review of the literature using different search engines (PubMed, ISI Web of Science, and the Cochrane Library) employing MeSH terms such as "Photodynamic therapy" and "PDT" in conjunction with other terms. We utilized the Population, Intervention, Comparison, Outcomes, and Study design (PICOS) method to define our study eligibility criteria.

RESULTS

Initial results were 1513. Finally, there were only 21 studies that met our selection criteria. We divided the 21 selected items into two groups: inflammatory diseases and infective diseases.

CONCLUSIONS

Although topical PDT is an easy to perform and well-tolerated treatment and appears to be a valid method with promising results in the treatment of benign lesions of the oral cavity's soft tissues, further studies are needed to complete the current knowledge of this technique.

Host Immune Response Triggered by Graphene Quantum-Dot-Mediated Photodynamic Therapy for Oral Squamous Cell Carcinoma

Introduction

With the innovation of photosensitizers, photodynamic therapy is now widely used in antitumor detection and treatment. Graphene quantum dots (GQDs) are proposed as a promising alternative photosensitizer due to their high biocompatibility, specific photoactivity, and strong tumor concentration. However, the changes in host immunity triggered by GQDs have only rarely been reported.

Methods

In this work, GQDs as photosensitizers were conjugated to polyethylene glycol (PEG) to enhance solubility and blood circulation. The phototoxicity of the resulting GQD-PEG nanomaterials was then detected in vitro and in vivo. The antitumor immunity triggered by GQD-PEG under irradiation was further evaluated in an oral squamous cell carcinoma animal model.

Results

The obtained GQD-PEG nanomaterials exhibited low cytotoxicity, good solution stability, and excellent endocytosis. Both in vitro and in vivo, all demonstrated strong ablation for oral squamous cell carcinoma under irradiation. Meanwhile, host-immunity-related CD8⁺ T cells (cytotoxic T lymphocytes) and proinflammatory cytokines, including IFN-γ and TNF-α, were significantly increased after photo-activated antitumor activity.

Conclusion

These results highlight the dominant role of GQD-PEG in photodynamic therapy and could have significant implications for further combination therapy as a promising antitumor immune response strategy triggered by nanomaterials.

Innovations for prevention and care of oral candidiasis in HIV-infected individuals: Are they available?-A workshop report

Oral candidiasis (OC) is the most prevalent HIV-related oral lesion in patients on combined anti-retroviral therapy (cART) or without cART. Management is challenged in some patients by development of resistance to azole drugs, such as fluconazole. Recent scientific knowledge about OC pathogenesis, the role of OC in the immune reconstitution inflammatory syndrome (IRIS), the relationship of OC with the microbiome, and novelties in OC treatment was discussed in an international workshop format. Literature searches were conducted to address five questions: (a) Considering the pathogenesis of Candida spp. infection, are there any potential therapeutic targets that could be considered, mainly in HIV-infected individuals resistant to fluconazole? (b) Is oral candidiasis part of IRIS in HIV patients who receive cART? (c) Can management of the oral microbiome reduce occurrence of OC in patients with HIV infection? (d) What are the recent advances (since 2015) regarding plant-based and alternative medicines in management of OC? and (e) Is there a role for photodynamic therapy in management of OC in HIV-infected patients? A number of the key areas where further research is necessary were identified to allow a deeper insight into this oral condition that could help to understand its nature and recommend alternatives for care.

Effect of Photodynamic Therapy on Cyclin D1 and P53 mRNA Levels in Head and Neck Squamous Cell Carcinoma Cell Line

Background: Photodynamic Therapy (PDT) is considered as one of the alternative treatments for Head and Neck Squamous Cell Carcinoma (HNSCC). P53 mRNA is a tumor suppressor gene whose mutation increases the likelihood of uncontrolled cancer-like divisions. The mutation of CCND1 oncogenic increases the production of cyclin D1 as a tumorigenic protein. Objectives: This study aimed to determine the effect of PDT using toluidine blue as a photosensitizer on the CCND1 and P53 mRNA levels in the HNSCC cell line. Methods: A human HNSCC cell line from NCBI.C196 designation HN5 was used. Cells were divided into four groups: Group I (HNSCC cell line under the influence of toluidine blue and laser irradiation), group II (HNSCC cell line under the influence of toluidine blue), group III (HNSCC cell line under laser irradiation), group IV (control group, HNSCC cell line). A 660 nm THOR laser using toluidine blue as a photosensitizer was applied. The RNA extraction was performed in three steps, including cell degradation, purification, and precipitation by alcohol. The cDNA was prepared using Takara Kit. The Amplicon kit and Real-Time PCR analysis were used for the assessment of mRNA relative levels. Results: The P53 mRNA relative levels were 1.50 ± 0.33 in group I (P = 0.65), 1.49 ± 0.23 (P =0.5) in group II, and 1.40 ± 1.05 (P = 0.63) in group III. Compared to the control group, the mean increases in CCND1 mRNA were 18.01 ± 3.37 (p=0.04) in group I, 17.69 ± 3.3 (P = 0.03) in group II, and 9.01 ± 6.17 (P = 0.20) in group III. Conclusions: The comparison of the fold change index for P53 and CCND1 mRNA by the one-way ANOVA test showed that despite the increased expression of P53 and CCND1 mRNA in treatment groups compared to the control group, there was no statistically significant difference between the increases in P53 mRNA (P = 0.99) and CCND1 mRNA (P = 0.22) index between the groups. The results of this study could be a starting point for a better understanding of the mechanism of genes in PDT of the HNSCC cell line.

Medical Gas Plasma Jet Technology Targets Murine Melanoma in an Immunogenic Fashion

Medical technologies from physics are imperative in the diagnosis and therapy of many types of diseases. In 2013, a novel cold physical plasma treatment concept was accredited for clinical therapy. This gas plasma jet technology generates large amounts of different reactive oxygen and nitrogen species (ROS). Using a melanoma model, gas plasma technology is tested as a novel anticancer agent. Plasma technology derived ROS diminish tumor growth in vitro and in vivo. Varying the feed gas mixture modifies the composition of ROS. Conditions rich in atomic oxygen correlate with killing activity and elevate intratumoral immune-infiltrates of CD8+ cytotoxic T-cells and dendritic cells. T-cells from secondary lymphoid organs of these mice stimulated with B16 melanoma cells ex vivo show higher activation levels as well. This correlates with immunogenic cancer cell death and higher calreticulin and heat-shock protein 90 expressions induced by gas plasma treatment in melanoma cells. To test the immunogenicity of gas plasma treated melanoma cells, 50% of mice vaccinated with these cells are protected from tumor growth compared to 1/6 and 5/6 mice negative control (mitomycin C) and positive control (mitoxantrone), respectively. Gas plasma jet technology is concluded to provide immunoprotection against malignant melanoma both in vitro and in vivo.

Nanotechnology in Oral Cavity Carcinoma: Recent Trends and Treatment Opportunities

Oral cavity carcinoma (OCC) remains an ongoing public health problem. Emerging nanotechnology provides alternative treatment approaches. This review covers the up-to-date literature in the human OCC treatment field. We explored the growing body of evidence to reveal novel and highly promising diagnostic and therapeutic applications of nanotechnology in this field. Various types of nanoparticles have been tested for applications in OCC. Imaging modalities in addition to nanocarriers are discussed. The encouraging contribution of lymphotropic nanoparticles contrast in the diagnosis of metastatic cervical lymph nodes needs to be confirmed. The development of the sentinel lymph node procedure and photodynamic therapy may lead to breakthrough therapies in order improve clinical outcomes and quality of life. In this perspective, cancer nanotechnology has the potential to revolutionize the treatment of OCC patients.

Stroma-Rich Co-Culture Multicellular Tumor Spheroids as a Tool for Photoactive Drugs Screening

Conventional 3D multicellular tumor spheroids of head and neck squamous cell carcinoma (HNSCC) consisting exclusively of cancer cells have some limitations. They are compact cell aggregates that do not interact with their extracellular milieu, thus suffering from both insufficient extracellular matrix (ECM) deposition and absence of different types of stromal cells. In order to better mimic in vivo HNSCC tumor microenvironment, we have constructed a 3D stroma-rich in vitro model of HNSCC, using cancer-associated MeWo skin fibroblasts and FaDu pharynx squamous cell carcinoma. The expression of stromal components in heterospheroids was confirmed by immunochemical staining. The generated co-culture FaDu/MeWo spheroids were applied to study penetration, distribution and antitumor efficacy of photoactive drugs such as Temoporfin and Chlorin e6 used in the photodynamic therapy flow cytometry and fluorescence microscopy techniques. We also investigated the distribution of photodiagnostic agent Indocyanine Green. We demonstrated that the presence of stroma influences the behavior of photoactive drugs in different ways: (i) No effect on Indocyanine Green distribution; (ii) lower accumulation of Chlorin e6; (iii) better penetration and PDT efficiency of Temoporfin. Overall, the developed stroma-rich spheroids enlarge the arsenal of in vitro pre-clinical models for high-throughput screening of anti-cancer drugs.

Gold as a Possible Alternative to Platinum-Based Chemotherapy for Colon Cancer Treatment

Due to the increasing incidence and high mortality associated with colorectal cancer (CRC), novel therapeutic strategies are urgently needed. Classic chemotherapy against CRC is based on oxaliplatin and other cisplatin analogues; however, platinum-based therapy lacks selectivity to cancer cells and leads to deleterious side effects. In addition, tumor resistance to oxaliplatin is related to chemotherapy failure. Gold(I) derivatives are a promising alternative to platinum complexes, since instead of interacting with DNA, they target proteins overexpressed on tumor cells, thus leading to less side effects than, but a comparable antitumor effect to, platinum derivatives. Moreover, given the huge potential of gold nanoparticles, the role of gold in CRC chemotherapy is not limited to gold(I) complexes. Gold nanoparticles have been found to be able to overcome multidrug resistance along with reduced side effects due to a more efficient uptake of classic drugs. Moreover, the use of gold nanoparticles has enhanced the effect of traditional therapies such as radiotherapy, photothermal therapy, or photodynamic therapy, and has displayed a potential role in diagnosis as a consequence of their optic properties. Herein, we have reviewed the most recent advances in the use of gold(I) derivatives and gold nanoparticles in CRC therapy.

Gold Nanoparticles in Diagnostics and Therapeutics for Human Cancer

The application of nanotechnology for the treatment of cancer is mostly based on early tumor detection and diagnosis by nanodevices capable of selective targeting and delivery of chemotherapeutic drugs to the specific tumor site. Due to the remarkable properties of gold nanoparticles, they have long been considered as a potential tool for diagnosis of various cancers and for drug delivery applications. These properties include high surface area to volume ratio, surface plasmon resonance, surface chemistry and multi-functionalization, facile synthesis, and stable nature. Moreover, the non-toxic and non-immunogenic nature of gold nanoparticles and the high permeability and retention effect provide additional benefits by enabling easy penetration and accumulation of drugs at the tumor sites. Various innovative approaches with gold nanoparticles are under development. In this review, we provide an overview of recent progress made in the application of gold nanoparticles in the treatment of cancer by tumor detection, drug delivery, imaging, photothermal and photodynamic therapy and their current limitations in terms of bioavailability and the fate of the nanoparticles.

Evaluation and Management of Oral Potentially Malignant Disorders

Oral potentially malignant disorders (OPMDs) refer to epithelial lesions and conditions with an increased risk for malignant transformation; oral leukoplakia is the most commonly encountered. Overall, OPMDs have a low risk for malignant transformation, yet the challenge is the difficulty to reliably identify and predict which patients with OPMDs are at the highest risk for malignant transformation. Future research is needed to elucidate the molecular aspects of OPMDs, to improve current diagnostic strategies, leading to personalized management.