Endothelial-Specific Overexpression of Histone Deacetylase 2 Protects Mice against Endothelial Dysfunction and Atherosclerosis.

BACKGROUND/AIMS: We recently described a novel regulatory role for histone deacetylase 2 (HDAC2) in protecting endothelial cells from oxidized low-density lipoprotein (OxLDL)-induced injury. In this study, we examined the effects of endothelial-specific HDAC2 overexpression on endothelial-dependent vasorelaxation and atherogenesis in vivo. METHODS: Endothelial-specific HDAC2-overexpressing transgenic mice (HDAC2-Tg) were generated under control of the Tie2 promoter. An atherosclerosis model was produced by injecting HDAC2-Tg and wild-type (WT) mice with adeno-associated virus encoding a PCSK9 gain-of-function mutant under control of a liver-specific promoter and feeding them a high-fat diet for 12 weeks. Aortic stiffness in vivo was determined by measuring pulse wave velocity. Wire myography was used to measure endothelium dependent (acetylcholine) and independent (sodium nitroprusside) relaxation in isolated mice aortas. Atherosclerotic plaque burden in aortas was determined by Oil Red O staining and protein expression was determined by western blotting. RESULTS: At baseline, HDAC2-Tg mice had normal mean arterial blood pressure (MAP) and body weight, but pulse wave velocity (PWV), an inverse measure of vascular health and stiffness, was decreased, suggesting that their vessels were more compliant. Moreover, basal nitric oxide production was enhanced in the vessels of HDAC2-Tg mice as compared to that in WT controls, although no significant differences in acetylcholine (endothelial component)- or sodium nitroprusside (non-endothelial component)-mediated relaxation were observed. However, after exposure to OxLDL, aortas from HDAC2-Tg mice exhibited greater acetylcholine-induced relaxation than did those from WT mice. Thus, endothelial-specific vasodilator production was enhanced despite oxidative injury. Atherosclerosis induction in WT mice led to a significant increase in PWV, but in HDAC2-Tg mice, PWV and MAP remained unchanged. Further, aortic rings from HDAC2-Tg exhibited better endothelial-dependent vascular relaxation than did those from WT mice, but not when treated with nitric oxide synthase inhibitor L-NAME. Finally, plaque burden, determined by Oil red O staining, was significantly increased in WT, but not HDAC2-Tg mice, subjected to the atherogenic model. Deletion of endothelial HDAC2 led to impaired endothelial cell-dependent vascular relaxation and increased PWV, compared with those in littermate controls. CONCLUSION: HDAC2 protects against endothelial dysfunction and atherogenesis induced by oxidized lipids. Hence, overexpression or activation of HDAC2 represents a novel therapy for endothelial dysfunction and atherosclerosis. HDAC2-Tg mice provide an opportunity to determine the role of endothelial HDAC2 in vascular endothelial homeostasis.

Hypoxia Triggers SENP1 (Sentrin-Specific Protease 1) Modulation of KLF15 (Kruppel-Like Factor 15) and Transcriptional Regulation of Arg2 (Arginase 2) in Pulmonary Endothelium.

OBJECTIVE: KLF15 (Kruppel-like factor 15) has recently been shown to suppress activation of proinflammatory processes that contribute to atherogenesis in vascular smooth muscle, however, the role of KLF15 in vascular endothelial function is unknown. Arginase mediates inflammatory vasculopathy and vascular injury in pulmonary hypertension. Here, we tested the hypothesis that KLF15 is a critical regulator of hypoxia-induced Arg2 (arginase 2) transcription in human pulmonary microvascular endothelial cells (HPMEC). APPROACH AND RESULTS: Quiescent HPMEC express ample amounts of full-length KLF15. HPMECs exposed to 24 hours of hypoxia exhibited a marked decrease in KLF15 protein levels and a reciprocal increase in Arg2 protein and mRNA. Chromatin immunoprecipitation indicated direct binding of KLF15 to the Arg2 promoter, which was relieved with HPMEC exposure to hypoxia. Furthermore, overexpression of KLF15 in HPMEC reversed hypoxia-induced augmentation of Arg2 abundance and arginase activity and rescued nitric oxide (NO) production. Ectopic KLF15 also reversed hypoxia-induced endothelium-mediated vasodilatation in isolated rat pulmonary artery rings. Mechanisms by which hypoxia regulates KLF15 abundance, stability, and compartmentalization to the nucleus in HPMEC were then investigated. Hypoxia triggered deSUMOylation of KLF15 by SENP1 (sentrin-specific protease 1), and translocation of KLF15 from nucleus to cytoplasm. CONCLUSIONS: KLF15 is a critical regulator of pulmonary endothelial homeostasis via repression of endothelial Arg2 expression. KLF15 abundance and nuclear compartmentalization are regulated by SUMOylation/deSUMOylation-a hypoxia-sensitive process that is controlled by SENP1. Strategies including overexpression of KLF15 or inhibition of SENP1 may represent novel therapeutic targets for pulmonary hypertension.

Present and future perspectives of photodynamic therapy for cutaneous squamous cell carcinoma.

Cutaneous squamous cell carcinoma (SCC) is the second most common skin cancer. Surgery remains the main stay of treatment, but some patients are not eligible for surgery and, more importantly, lesions at critical sites need nonsurgical approaches for tissue preservation. In this context, photodynamic therapy (PDT) has been extensively studied as noninvasive or minimally invasive treatment, and studies have shown promising results in terms of safety, efficacy, and cosmetic outcome. Also, studies have proposed different mechanism for its efficacy. However, human studies demonstrating its efficacy are limited in terms of sample size and tumor depth of invasion. Good results are mainly seen in case reports of microinvasive SCC, which is defined as SCC limited to papillary dermis. This inadequacy is due to inadequate penetration of topically applied photosensitizers through keratinized tumor surfaces. To overcome these hurdles, pretreatment with lasers or microneedles and encapsulation of photosensitizers into nanoparticles have been tried. Hence, the present article will discuss studies that have demonstrated the efficacy and safety of PDT for cutaneous SCC, studies that have postulated the mechanism of action of PDT, agents that have been used as PDT enhancers, and finally, the recent use of adjuvant therapy in combination with PDT.

Opsin 3 and 4 mediate light-induced pulmonary vasorelaxation that is potentiated by G protein-coupled receptor kinase 2 inhibition.

We recently demonstrated that blue light induces vasorelaxation in the systemic mouse circulation, a phenomenon mediated by the nonvisual G protein-coupled receptor melanopsin (Opsin 4; Opn4). Here we tested the hypothesis that nonvisual opsins mediate photorelaxation in the pulmonary circulation. We discovered Opsin 3 (Opn3), Opn4, and G protein-coupled receptor kinase 2 (GRK2) in rat pulmonary arteries (PAs) and in pulmonary arterial smooth muscle cells (PASMCs), where the opsins interact directly with GRK2, as demonstrated with a proximity ligation assay. Light elicited an intensity-dependent relaxation of PAs preconstricted with phenylephrine (PE), with a maximum response between 400 and 460 nm (blue light). Wavelength-specific photorelaxation was attenuated in PAs from Opn4-/- mice and further reduced following shRNA-mediated knockdown of Opn3. Inhibition of GRK2 amplified the response and prevented physiological desensitization to repeated light exposure. Blue light also prevented PE-induced constriction in isolated PAs, decreased basal tone, ablated PE-induced single-cell contraction of PASMCs, and reversed PE-induced depolarization in PASMCs when GRK2 was inhibited. The photorelaxation response was modulated by soluble guanylyl cyclase but not by protein kinase G or nitric oxide. Most importantly, blue light induced significant vasorelaxation of PAs from rats with chronic pulmonary hypertension and effectively lowered pulmonary arterial pressure in isolated intact perfused rat lungs subjected to acute hypoxia. These findings show that functional Opn3 and Opn4 in PAs represent an endogenous "optogenetic system" that mediates photorelaxation in the pulmonary vasculature. Phototherapy in conjunction with GRK2 inhibition could therefore provide an alternative treatment strategy for pulmonary vasoconstrictive disorders.

3D Hybrid Small Scale Devices.

Interfacing nano/microscale elements with biological components in 3D contexts opens new possibilities for mimicry, bionics, and augmentation of organismically and anatomically inspired materials. Abiotic nanoscale elements such as plasmonic nanostructures, piezoelectric ribbons, and thin film semiconductor devices interact with electromagnetic fields to facilitate advanced capabilities such as communication at a distance, digital feedback loops, logic, and memory. Biological components such as proteins, polynucleotides, cells, and organs feature complex chemical synthetic networks that can regulate growth, change shape, adapt, and regenerate. Abiotic and biotic components can be integrated in all three dimensions in a well-ordered and programmed manner with high tunability, versatility, and resolution to produce radically new materials and hybrid devices such as sensor fabrics, anatomically mimetic microfluidic modules, artificial tissues, smart prostheses, and bionic devices. In this critical Review, applications of small scale devices in 3D hybrid integration, biomicrofluidics, advanced prostheses, and bionic organs are discussed.

Vertikale Übertragung des Herpes-simplex-Virus: eine Aktualisierung.

Infektionen mit den Herpes-simplex-Viren (HSV)-1 und -2 haben weltweit eine hohe Prävalenz. Eine HSV-Infektion während der Schwangerschaft kann eine neonatale Herpes-Infektion verursachen, die durch eine lebenslange Infektion mit Latenz- und Reaktivierungsperioden gekennzeichnet ist. Ein Säugling kann sich in utero (5 %), peripartal (85 %) oder postnatal (10 %) mit dem HS-Virus infizieren. Herpes neonatorum ist eine seltene aber bedeutsame Infektion, die mit schwerer Morbidität und Mortalität assoziiert sein kann, insbesondere bei Dissemination oder Beteiligung des zentralen Nervensystems. Fortschritte bei Diagnose und Therapie haben zur Verringerung der Mortalität sowie, in geringerem Ausmaß, zu einem verbesserten neurologischen Outcome geführt. Dennoch sind weitere Verbesserungen wünschenswert. Dabei ist es entscheidend, Ärzte in die Lage zu versetzen, diejenigen Säuglinge, die einem erhöhten Risiko einer HSV-Infektion ausgesetzt sind, zu erkennen und die Mutter-Kind-Übertragung effektiver zu verhindern. Ein lohnendes Ziel für die Zukunft ist die Entwicklung neuer antiviraler Wirkstoffe mit höherer Wirksamkeit.

Vertical transmission of herpes simplex virus: an update.

Herpes simplex virus (HSV)-1 and -2 infections are highly prevalent worldwide. HSV infection during pregnancy can result in neonatal herpes infection, which is characterized by lifelong infection with periods of latency and reactivation. HSV can be acquired by an infant during one of three periods: in utero (5 %), peripartum (85 %), or postnatal (10 %). Neonatal HSV is a rare but significant infection that may be associated with severe morbidity and mortality, especially if there is dissemination or central nervous system involvement. Diagnostic and therapeutic advances have led to a reduction in mortality and, to a lesser extent, improvement of neurodevelopmental outcomes, but further developments are still needed. It is essential to improve the clinician's ability to identify infants who are at increased risk of HSV infection and to prevent mother-to-child transmission. The development of novel antiviral agents with higher efficacy is a worthwhile aim for the future.

Cystathionine γ-lyase protects vascular endothelium: a role for inhibition of histone deacetylase 6.

Endothelial cystathionine γ-lyase (CSEγ) contributes to cardiovascular homeostasis, mainly through production of H2S. However, the molecular mechanisms that control CSEγ gene expression in the endothelium during cardiovascular diseases are unclear. The aim of the current study is to determine the role of specific histone deacetylases (HDACs) in the regulation of endothelial CSEγ. Reduced CSEγ mRNA expression and protein abundance were observed in human aortic endothelial cells (HAEC) exposed to oxidized LDL (OxLDL) and in aortas from atherogenic apolipoprotein E knockout (ApoE-/-) mice fed a high-fat diet compared with controls. Intact murine aortic rings exposed to OxLDL (50 µg/ml) for 24 h exhibited impaired endothelium-dependent vasorelaxation that was blocked by CSEγ overexpression or the H2S donor NaHS. CSEγ expression was upregulated by pan-HDAC inhibitors and by class II-specific HDAC inhibitors, but not by other class-specific inhibitors. The HDAC6 selective inhibitor tubacin and HDAC6-specific siRNA increased CSEγ expression and blocked OxLDL-mediated reductions in endothelial CSEγ expression and CSEγ promoter activity, indicating that HDAC6 is a specific regulator of CSEγ expression. Consistent with this finding, HDAC6 mRNA, protein expression, and activity were upregulated in OxLDL-exposed HAEC, but not in human aortic smooth muscle cells. HDAC6 protein levels in aortas from high-fat diet-fed ApoE-/- mice were comparable to those in controls, whereas HDAC6 activity was robustly upregulated. Together, our findings indicate that HDAC6 is upregulated by atherogenic stimuli via posttranslational modifications and is a critical regulator of CSEγ expression in vascular endothelium. Inhibition of HDAC6 activity may improve endothelial function and prevent or reverse the development of atherosclerosis.NEW & NOTEWORTHY Oxidative injury to endothelial cells by oxidized LDL reduced cystathionine γ-lyase (CSEγ) expression and H2S production, leading to endothelial dysfunction, which was prevented by histone deacetylase 6 (HDAC6) inhibition. Our data suggest HDAC6 as a novel therapeutic target to prevent the development of atherosclerosis.

Obesity-induced vascular inflammation involves elevated arginase activity.

Obesity-induced vascular dysfunction involves pathological remodeling of the visceral adipose tissue (VAT) and increased inflammation. Our previous studies showed that arginase 1 (A1) in endothelial cells (ECs) is critically involved in obesity-induced vascular dysfunction. We tested the hypothesis that EC-A1 activity also drives obesity-related VAT remodeling and inflammation. Our studies utilized wild-type and EC-A1 knockout (KO) mice made obese by high-fat/high-sucrose (HFHS) diet. HFHS diet induced increases in body weight, fasting blood glucose, and VAT expansion. This was accompanied by increased arginase activity and A1 expression in vascular ECs and increased expression of tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), interleukin-10 (IL-10), vascular cell adhesion molecule-1 (VCAM-1), and intercellular adhesion molecule-1 (ICAM-1) mRNA and protein in both VAT and ECs. HFHS also markedly increased circulating inflammatory monocytes and VAT infiltration by inflammatory macrophages, while reducing reparative macrophages. Additionally, adipocyte size and fibrosis increased and capillary density decreased in VAT. These effects of HFHS, except for weight gain and hyperglycemia, were prevented or reduced in mice lacking EC-A1 or treated with the arginase inhibitor 2-(S)-amino-6-boronohexanoic acid (ABH). In mouse aortic ECs, exposure to high glucose (25 mM) and Na palmitate (200 µM) reduced nitric oxide production and increased A1, TNF-α, VCAM-1, ICAM-1, and MCP-1 mRNA, and monocyte adhesion. Knockout of EC-A1 or ABH prevented these effects. HFHS diet-induced VAT inflammation is mediated by EC-A1 expression/activity. Limiting arginase activity is a possible therapeutic means of controlling obesity-induced vascular and VAT inflammation.

A review of the mechanism of action of lasers and photodynamic therapy for onychomycosis.

Onychomycosis is one of the most common diseases in the field of dermatology. It refers to the fungal infection of the nail plate or nail bed with high incidence in the general population. The available treatment options for onychomycosis have limited use due to side effects, drug interactions, and contraindications, which necessitates the application of an alternative treatment for onychomycosis. In the recent years, lasers and photodynamic therapy (PDT) have been recognized as alternative treatment options. Most of the previous studies have found them to be safe and effective treatment modalities in this indication; however, the results varied greatly and the in vitro and in vivo outcomes are contradictory. In the present review, studies related to the mechanism of action of lasers and PDT for the treatment of onychomycosis will be discussed, with a focus on to find explanation to the contradictory results.

Fractional carbon-dioxide (CO2) laser-assisted topical therapy for the treatment of onychomycosis.

BACKGROUND: Inability of topical medications to penetrate via nail plate brings a great challenge to clinicians in treating onychomycosis. Furthermore, oral medications are not appropriate for all patients because of drug interactions, adverse effects, and contraindications. OBJECTIVE: We sought to evaluate the clinical efficacy of fractional carbon-dioxide laser-assisted topical therapy for onychomycosis. METHODS: In total, 75 patients with 356 onychomycotic nails confirmed by mycologic examination were included in this study. All the affected nails received 3 sessions of laser therapy at 4-week intervals and once-daily application of terbinafine cream for 3 months. RESULTS: In all, 94.66% and 92% of the treated patients were potassium hydroxide and culture negative, respectively, after 3 months of treatment. However, only 84% and 80% were potassium hydroxide and culture negative, respectively, at 6 months of follow-up. Using Scoring Clinical Index for Onychomycosis electronic calculator, 73.33% of the patients scored higher than 6 and 26.66% of the patients scored 6 or less. Those who scored more than 6 were evaluated clinically and 98.18% of them showed response to treatment at 3 months and 78.18% of them at 6 months of follow-up. LIMITATION: Lack of control group and short duration of follow-up are limitations. CONCLUSIONS: Fractional carbon-dioxide laser therapy combined with topical antifungal was found to be effective in the treatment of onychomycosis. However, randomized clinical studies are needed before it can be widely used in clinics.

Arginase inhibition enhances angiogenesis in endothelial cells exposed to hypoxia.

Hypoxia-induced arginase elevation plays an essential role in several vascular diseases but influence of arginase on hypoxia-mediated angiogenesis is completely unknown. In this study, in vitro network formation in bovine aortic endothelial cells (BAEC) was examined after exposure to hypoxia for 24h with or without arginase inhibition. Arginase activity, protein levels of the two arginase isoforms, eNOS, and VEGF as well as production of NO and ROS were examined to determine the involvement of arginase in hypoxia-mediated angiogenesis. Hypoxia elevated arginase activity and arginase 2 expression but reduced active p-eNOS(Ser1177) and NO levels in BAEC. In addition, both VEGF protein levels and endothelial elongation and network formation were reduced with continued hypoxia, whereas ROS levels increased and NO levels decreased. Arginase inhibition limited ROS, restored NO formation and VEGF expression, and prevented the reduction of angiogenesis. These results suggest a fundamental role of arginase activity in regulating angiogenic function.

Laser treatment for onychomycosis: a review.

It has always been difficult to treat onychomycosis due to decrease ability of topical agents to penetrate the nail and reach the affected nail bed. Oral antifungal have shown good response but due to longer duration course it has potential to cause systemic side effects, leading to patient non-adherence and adverse events. Lasers, therefore, have been suggested for the treatment of onychomycosis due to their minimally invasive nature and the potential for requiring fewer treatment sessions. The aim of writing this article is to review a literature regarding treatment of onychomycosis by laser. This article will discuss about all the available laser treatment options for onychomycosis as well as their currently published, peer-reviewed literature.

Photodynamic therapy as an alternative treatment in patients with invasive cutaneous SCC where surgery is not feasible: Single center experience.

The aim of this study was to demonstrate the efficacy of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) as an alternative treatment in cutaneous squamous cell carcinoma (cSCC) patients who are not fit for surgery. Thirty-three invasive cSCC patients who, for some reasons, cannot undergo surgery were enrolled in this study. All patients received plum blossom needle (PBN) pretreated ALA-PDT combined with topical application of 5% imiquimod cream. Two patients dropped the study because of severe pain and two patients discontinue treatment due to lack of response. Of 29 patients, who completed the treatment, 5 patients had complete response after 2-9 sessions of PDT and these patients had no recurrence till 18 months after treatment. Twenty-four patients achieved partial response and are satisfied with treatment outcome in terms of decreased symptoms and improved quality of life. PBN pretreated PDT in combination with topical imiquimod may be a viable treatment option for non resectable cSCC lesions.

Biomimetic human small muscular pulmonary arteries.

Changes in structure and function of small muscular arteries play a major role in the pathophysiology of pulmonary hypertension, a burgeoning public health challenge. Improved anatomically mimetic in vitro models of these microvessels are urgently needed because nonhuman vessels and previous models do not accurately recapitulate the microenvironment and architecture of the human microvascular wall. Here, we describe parallel biofabrication of photopatterned self-rolled biomimetic pulmonary arterial microvessels of tunable size and infrastructure. These microvessels feature anatomically accurate layering and patterning of aligned human smooth muscle cells, extracellular matrix, and endothelial cells and exhibit notable increases in endothelial longevity and nitric oxide production. Computational image processing yielded high-resolution 3D perspectives of cells and proteins. Our studies provide a new paradigm for engineering multicellular tissues with precise 3D spatial positioning of multiple constituents in planar moieties, providing a biomimetic platform for investigation of microvascular pathobiology in human disease.

CCL8 enhances sensitivity of cutaneous squamous cell carcinoma to photodynamic therapy by recruiting M1 macrophages.

BACKGROUND: Antitumor immunity induced by photodynamic therapy (PDT) is believed to depend on the degree of local and systemic inflammation. The recruitment of leukocytes, in particular by the chemokine CCL8, to the sites of tissue damage has been strongly associated with the initiation of inflammatory reactions. OBJECTIVE: To evaluate whether and how CCL8 enhances the immune response against tumors in 5-aminolevulinic acid (ALA)-mediated PDT. METHODS: In this study, we investigated the effect of ALA-PDT-induced CCL8 expression on the recruitment and polarization of macrophages using immunohistochemistry, western blot and Transwell cell migration assay. We evaluated CCL8 expression following ALA-PDT in vitro and in vivo by using RT-PCR, western blot, and ELISA in clinical cutaneous squamous cell carcinoma (cSCC) samples, a mouse model of cSCC, tumor cells, and macrophages. The effect of the combination of ALA-PDT with CCL8 treatment on anti-tumor immunity was tested in the mouse model. RESULTS: We found that ALA-PDT enhanced CCL8 expression, increased the number of macrophages in tumor, and stimulated their M1 pro-inflammatory phenotype characterized by high expression levels of CD16 and CD80, low expression level of CD163, and absence of CD206 expression. Furthermore, CCL8 enhanced the effect of ALA-PDT on cSCC in mice, such a combination of CCL8 and ALA-PDT had a stronger positive effect in the treatment of mouse cSCC than PDT alone and suppressed tumor volume regrowth. CONCLUSION: ALA-PDT induces CCL8 expression and recruits M1 macrophages, thus suppressing tumor growth.

Dermatologic manifestations of inflammatory bowel disease: a review.

Inflammatory bowel disease (IBD) is a chronic relapsing disease of the gastrointestinal tract with unknown etiology and pathogenesis. It includes Crohn's disease (CD) and ulcerative colitis (UC). Approximately one-third of the patients with IBD are seen to develop extraintestinal manifestations, among which cutaneous manifestations are the most common and should be managed in close collaboration with a dermatologist. Depending upon the nature of the association, skin conditions associated with IBD can be listed under 4 categories: specific, reactive, secondary to malnutrition or malabsorption, and secondary to drug therapy. Skin conditions that do not fit into these categories are listed under the fifth category named as miscellaneous by some authors. The aim of the present review is to discuss some of the noteworthy skin disorders associated with IBD and highlight their importance in context to IBD.

Application of high frequency ultrasound in dermatology.

High frequency ultrasound (HFUS) refers to the ultrasound probe frequency of more than 10 MHz. HFUS has shorter wavelengths, is absorbed more easily, and is therefore not as penetrating. This explains its use for superficial structures and hence its increasing application in the field of dermatology. HFUS is a simple, reliable, and noninvasive technique that is being used along with the physical examination for the assessment, diagnosis, and management of many dermatologic conditions. In addition, it can also be used for the evaluation of normal skin structure. In the present article, we aim to describe the basic principles of cutaneous ultrasound, imaging findings of normal skin, and current applications of HFUS in the diagnosis, treatment, and follow-up of various dermatologic conditions.

Therapeutic effect of Imiquimod enhanced ALA-PDT on cutaneous squamous cell carcinoma.

BACKGROUND: Topical photodynamic therapy (PDT) is approved treatment for actinic keratosis, basal cell carcinoma and Bowen's disease. But currently it is not recommended for invasive squamous cell carcinoma (SCC) of the skin because inadequate penetration of topically applied photosensitizers lead to poor treatment response. Imiquimod (IMQ) as an immune response modifier and Toll-like receptor 7 (TLR7) agonist, is known to exhibit antitumor activity. As an adjunct therapy, it is recently seen to enhance the effect of PDT. METHOD: This is an in vivo experiment performed on 52 SCC implanted mice model. The mice were equally divided into four groups: IMQ group, IMQ + PDT group, PDT group and control group. The mice in IMQ + PDT group were treated with 3 sessions of 5% IMQ cream and ALA-PDT. Mice in IMQ group received only 5% IMQ cream. Similarly, mice in PDT group received only ALA-PDT and control mice received no treatment. The treatment efficacy was compared among these groups via tumor volume and digital photographs. In addition, immunohistochemical (IHC) markers, q PCR and detection of apoptosis were studied on 12 UV induced mice model. After successful result of this animal experiment, we performed human study on two patients with invasive cSCC on lips and foot. The patients were treated with daily application of 5% imiquimod cream and ALA-PDT at 2 weeks interval. Treatment response was assessed via clinical examination, digital photographs and dermoscopy findings. RESULTS: The study demonstrated that combination approach of IMQ + PDT has better effect than IMQ alone or PDT alone. It also showed increased expression of IL-6, IL-8, IFN-α, CXCL9, CXCL10 and TNF-α in IMQ + PDT group but at different time points following treatment (P < 0.05). IHC staining showed that the number of CD4+ cells was similar in IMQ + PDT and PDT groups but CD8+ cells was almost double in IMQ + PDT group when compared to PDT group. In addition, the number of apoptotic cell was maximum in IMQ + PDT group. Human study also delivered excellent results in both the patients with complete clearance of lesion after 3-6 sessions of treatment. CONCLUSION: PDT combined with imiquimod may have enhanced effect for the treatment of invasive cSCC. Maximum number of apoptotic cells in IMQ + PDT group can be attributed to increased number of CD8 + T cells in this group. Additional mechanism of enhanced efficacy in IMQ + PDT group may be due to increased expression of markers tested in this study.

Zinc pthalocyanine-loaded chitosan/mPEG-PLA nanoparticles-mediated photodynamic therapy for the treatment of cutaneous squamous cell carcinoma.

Zinc pthalocyanine (ZnPc) is a second-generation photodynamic therapy (PDT) sensitizer with sufficient PDT activity for squamous cell carcinoma (SCC). ZnPc is hydrophobic and insoluble in water, which creates hurdles in systemic administration and hence restricts its use in clinic. Here we have loaded ZnPc on chitosan/methoxy polyethylene glycol-polylactic acid (CPP) nanoparticles to form Z-CPP to enhance PDT efficacy. In vitro and in vivo studies were performed to see dark toxicity of the compounds ZnPc, CPP and Z-CPP. Then PDT was done and its growth inhibitory effect on SCC cells was evaluated. In addition, reactive oxygen species (ROS) formation and apoptosis of cancer cells following PDT were studied. The results showed that the tested compounds exhibit no dark toxicity and the effect of PDT was significantly better with Z-CPP when compared to free ZnPc (P < .05). Photoactivation of Z-CPP led to a dose-dependent growth inhibition of cancer cells of >50% at 1 µM to >80% at 10 µM concentration. Also Z-CPP-treated cells had highest number of apoptotic cells and produced more ROS compared to free ZnPc-treated cells (P < .05). Hence, this study suggests that Z-CPP is a suitable pharmaceutical compound to increase PDT efficacy.