The bright side of sound: perspectives on the biomedical application of sonoluminescence.

Light is a physical phenomenon that is very important to human life, and has been investigated in its nature, behaviour and properties throughout human history although the most impressive improvements in the use of light in human activities, and of course in medicine, began just two centuries ago. However, despite the enormous progress in diagnosis, therapy and surgery to assess health and treat diseases, the delivery of light sources in vivo remains a challenge. In this regard, several strategies have been developed to overcome this drawback, the most interesting of which is the involvement of ultrasound. In this review, the authors examine how ultrasound may improve light delivery in vivo with a special emphasis on one of the most intriguing ultrasound-mediated phenomena called sonoluminescence, which is the conversion of mechanical ultrasound energy into light.

Biological Effect Evaluation of Glutathione-Responsive Cyclodextrin-Based Nanosponges: 2D and 3D Studies.

This study aims to evaluate the bioeffects of glutathione-responsive ß-cyclodextrin-based nanosponges (GSH-NSs) on two- (2D) and three-dimensional (3D) cell cultures. The bioeffects of two types of GSH-NS formulations, with low (GSH-NS B) and high (GSH-NS D) disulfide-bond content, were evaluated on 2D colorectal (HCT116 and HT-29) and prostatic (DU-145 and PC3) cancer cell cultures. In particular, the cellular uptake of GSH-NS was evaluated, as their effects on cell growth, mitochondrial activity, membrane integrity, cell cycle distribution, mRNA expression, and reactive oxygen species production. The effect of GSH-NSs on cell growth was also evaluated on multicellular spheroids (MCS) and a comparison of the GSH-NS cell growth inhibitory activity, in terms of inhibition concentration (IC)50 values, was performed between 2D and 3D cell cultures. A significant decrease in 2D cell growth was observed at high GSH-NS concentrations, with the formulation with a low disulfide-bond content, GSH-NS B, being more cytotoxic than the formulation with a high disulfide-bond content, GSH-NS D. The cell growth decrease induced by GSH-NS was owing to G1 cell cycle arrest. Moreover, a significant down-regulation of mRNA expression of the cyclin genes CDK1, CDK2, and CDK4 and up-regulation of mRNA expression of the cyclin inhibitor genes CDKN1A and CDKN2A were observed. On the other hand, a significant decrease in MCS growth was also observed at high GSH-NS concentrations, but not influenced by the nanosponge disulfide-bond content, with the MCS IC50 values being significantly higher than those obtained on 2D cell cultures. GSH-NSs are suitable nanocarries as they provoke limited cellular effects, as cell cycle arrest only occurred at concentrations significantly higher than those used for drug delivery.

Recent Developments in Antibacterial Therapy: Focus on Stimuli-Responsive Drug-Delivery Systems and Therapeutic Nanoparticles.

Conventional drugs used for antibacterial therapy display several limitations. This is not due to antibiotics being ineffective, but rather due to their low bioavailability, limited penetration to sites of infection and the rise of drug-resistant bacteria. Although new delivery systems (e.g., nanoparticles) that are loaded with antibacterial drugs have been designed to overcome these limitations, therapeutic efficacy does not seem to have improved. Against this backdrop, stimuli-responsive antibiotic-loaded nanoparticles and materials with antimicrobial properties (nanoantibiotics) present the ability to enhance therapeutic efficacy, while also reducing drug resistance and side effects. These stimuli can either be exogenous (e.g., light, ultrasound) or endogenous (e.g., pH, variation in redox gradient, enzymes). This promising therapeutic approach relies on advances in materials science and increased knowledge of microorganism growth and biofilm formation. This review provides an overview in the field of antibacterial drug-delivery systems and nanoantibiotics that benefit from a response to specific triggers, and also presents a number of future prospects.

Donor CYP3A5 genotype influences tacrolimus disposition on the first day after paediatric liver transplantation.

AIM: The aim of the present study was to investigate the influence of the cytochrome P450 (CYP) 3A4/5 genotype in paediatric liver transplant recipients and donors, and the contribution of age and gender to tacrolimus disposition on the first day after transplantation. METHODS: The contribution of the CYP3A4/5 genotype in paediatric liver transplant recipients and donors to the tacrolimus blood trough concentrations (C0 ) and the tacrolimus concentration/weight-adjusted dose ratio on day 1 was evaluated in 67 liver-transplanted children: 33 boys and 34 girls, mean age 4.5 years. RESULTS: Donor CYP3A5 genotype appears to be significantly associated with tacrolimus disposition on the first day after liver transplantation (P < 0.0002). Other physiological factors, such as recipient age and donor gender may also play a role and lead to significant differences in tacrolimus C0 and tacrolimus concentration/weight-adjusted dose ratio on day 1. However, according to the general linear model, only recipient age appears to be independently associated with tacrolimus disposition on the first day after liver transplantation (P < 0.03). Indeed, there was a faster tacrolimus metabolism in children under 6 years of age (P < 0.02). CONCLUSIONS: Donor CYP3A5 genotype, recipient age and, to a lesser extent, donor gender appear to be associated with tacrolimus disposition on day 1 after transplant. This suggests that increasing the starting tacrolimus doses in paediatric patients under 6 years of age who receive a graft from a male extensive metabolizer may enhance the possibility of their tacrolimus levels reaching the therapeutic range sooner.

Targeting the NLRP3 Inflammasome to Reduce Diet-Induced Metabolic Abnormalities in Mice.

Although the molecular links underlying the causative relationship between chronic low-grade inflammation and insulin resistance are not completely understood, compelling evidence suggests a pivotal role of the nucleotide-binding oligomerization domain (NOD)-like receptor pyrin domain containing 3 (NLRP3) inflammasome. Here we tested the hypothesis that either a selective pharmacological inhibition or a genetic downregulation of the NLRP3 inflammasome results in reduction of the diet-induced metabolic alterations. Male C57/BL6 wild-type mice and NLRP3-/- littermates were fed control diet or high-fat, high-fructose diet (HD). A subgroup of HD-fed wild-type mice was treated with the NLRP3 inflammasome inhibitor BAY 11-7082 (3 mg/kg intraperitoneally [IP]). HD feeding increased plasma and hepatic lipids and impaired glucose homeostasis and renal function. Renal and hepatic injury was associated with robust increases in profibrogenic markers, while only minimal fibrosis was recorded. None of these metabolic abnormalities were detected in HD-fed NLRP3-/- mice, and they were dramatically reduced in HD-mice treated with the NLRP3 inflammasome inhibitor. BAY 11-7082 also attenuated the diet-induced increase in NLRP3 inflammasome expression, resulting in inhibition of caspase-1 activation and interleukin (IL)-1ß and IL-18 production (in liver and kidney). Interestingly, BAY 11-7082, but not gene silencing, inhibited nuclear factor (NF)-κB nuclear translocation. Overall, these results demonstrate that the selective pharmacological modulation of the NLRP3 inflammasome attenuates the metabolic abnormalities and the related organ injury/dysfunction caused by chronic exposure to HD, with effects similar to those obtained by NLRP3 gene silencing.

Modulation of butyrate anticancer activity by solid lipid nanoparticle delivery: an in vitro investigation on human breast cancer and leukemia cell lines.

PURPOSE: Histone modification has emerged as a promising approach to cancer therapy. The short-chain fatty acid, butyric acid, a histone deacetylase (HD) inhibitor, has shown anticancer activity. Butyrate transcriptional activation is indeed able to withdraw cancer cells from the cell cycle, leading to programmed cell death. Since butyrate's clinical use is hampered by unfavorable pharmacokinetic and pharmacodynamic properties, delivery systems, such as solid lipid nanoparticles (SLN), have been developed to overcome these constraints. METHODS: In order to outline the influence of butyrate delivery on its anticancer activity, the effects of butyrate as a free (sodium butyrate, NB) or nanoparticle (cholesteryl butyrate solid lipid nanoparticles, CBSLN) formulation on the growth of different human cancer cell lines, such as the promyelocytic leukemia, HL-60, and the breast cancer, MCF-7 was investigated. A detailed investigation into the mechanism of the induced cytotoxicity was also carried out, with a special focus on the modulation of HD and cyclin-dependent kinase (CDK) mRNA gene expression by real time PCR analysis. RESULTS: In HL-60 cells, CBSLN induced a higher and prolonged expression level of the butyrate target genes at lower concentrations than NB. This led to a significant decrease in cell proliferation, along with considerable apoptosis, cell cycle block in the G0/G1 phase, significant inhibition of total HD activity and overexpression of the p21 protein. Conversely, in MCF-7 cells, CBSLN did not enhance the level of expression of the butyrate target genes, leading to the same anticancer activity as that of NB. CONCLUSIONS: Solid lipid nanoparticles were able to improve butyrate anticancer activity in HL-60, but not in MCF-7 cells. This is consistent with difference in properties of the cells under study, such as expression of the TP53 tumor suppressor, or the transporter for short-chain fatty acids, SLC5A8.

Evaluation of the cytotoxic and immunomodulatory effects of sonodynamic therapy in human pancreatic cancer spheroids.

Sonodynamic therapy (SDT) exploits the energy generated by ultrasound (US) to activate sound-sensitive drugs (sonosensitizers), leading to the generation of reactive oxygen species (ROS) and cancer cell death. Two-dimensional (2D) and three-dimensional (3D) cultures of human pancreatic cancer BxPC-3 cells were chosen as the models with which to investigate the therapeutic effects of the US-activated sonosensitizer IR-780 as pancreatic cancer is still one of the most lethal types of cancer. The effects of SDT, including ROS production, cancer cell death and immunogenic cell death (ICD), were extensively investigated. When subjected to US, IR-780 triggered significant ROS production and caused cancer cell death after 24 h (p ≤ 0.01). Additionally, the activation of dendritic cells (DCs) led to an effective immune response against the cancer cells undergoing SDT-induced death. BxPC-3 spheroids were developed and studied extensively to validate the findings observed in 2D BxPC-3 cell cultures. An analysis of the pancreatic cancer spheroid section revealed significant SDT-induced cancer cell death after 48 h after the treatment (p ≤ 0.01), with this being accompanied by the presence of SDT-induced damage-associated molecular patterns (DAMPs), such as calreticulin (CRT) and high mobility group box 1 (HMGB1). In conclusion, the data obtained demonstrates the anticancer efficacy of SDT and its immunomodulatory potential via action as an ICD-inducer.

Exploring the redox potential induced by low-intensity focused ultrasound on tumor masses.

Cancer is still a major health problem worldwide despite huge efforts being spent on its biomedical research. Beyond the mainstream therapeutic interventions (i.e., surgery, chemotherapy, immunotherapy and radiotherapy), further significant progresses in anticancer therapy could rely on the development of novel treatment paradigms. To this end, one emerging approach consists in the use of non-thermal low-intensity focused ultrasound (LIFU) for conditioning cancer molecules and/or cancer-targeted compounds, thereby leading to cancer cell death with least side-effects. Cellular redox homeostasis manifested as the generation of reactive oxygen species (ROS) during energy metabolism as well as the antioxidant capacity is interwoven to the composition, size and anatomical location of the tumor masses. The higher content of "oxide free radicals" in cancers makes them vulnerable to disruption of redox homeostasis than in the healthy cells and therefore, one of the best options for preferentially eradicating them is increasing their oxidative stress, excessively. A little is known about the modulation of cellular redox homeostasis by LIFU, and so it will be of great interest and utility to understand the effects of LIFU on the energy metabolism of cancer cells. This review is intended to improve our knowledge on the effect of LIFU on cancer cells with particular reference to its redox metabolism for ultrasound-based therapies. Thereby, it could pave the way for exploring novel methodologies and designing combined anti-cancer therapies, especially, for faster and safer eradication of drug resistant and metastasizing solid tumors.

ROS-generating nanoplatforms as selective and tunable therapeutic weapons against cancer.

Reactive species refers to a group of chemicals, mainly reactive oxygen species (ROS) and reactive nitrogen species (RNS), that are naturally formed by cells as a byproduct of cell metabolism and regulated by various internal and external factors. Due to their highly chemical reactivity, ROS play a crucial role in physiological and pathological processes which is why studies on ROS regulation for disease treatment show attracted increasing interest. Notably, ROS are now studied as a powerful therapeutic weapon in ROS-regulating therapies such as ROS-based cytotoxic therapies mediated by ROS-increasing agents for cancer treatment. Thanks to the significant progress in nanotechnology, innovative nanoplatforms with ROS-regulating activities have been developed to look for effective ROS-related nanomedicines. In this review, studies on ROS-based cytotoxic therapies against cancer as photodynamic therapy (PDT), sonodynamic therapy (SDT), radiation therapy (RT) and chemodynamic therapy (CDT) are discussed, with a focus on the stimuli-responsive ROS-generating nanoplatforms developed for breaking the current therapeutic limits of ROS-based cytotoxic therapies. Finally, we suppose that our review on this developing field will be valuable for promoting the progress of ROS-based cytotoxic therapies not only in basic research but overall, in translational research and clinical application.

Development of ARPE-19-Equipped Ocular Cell Model for In Vitro Investigation on Ophthalmic Formulations.

Repeated intravitreal (IVT) injections in the treatment of retinal diseases can lead to severe complications. Developing innovative drug delivery systems for IVT administration is crucial to prevent adverse reactions, but requires extensive investigation including the use of different preclinical models (in vitro, ex vivo and in vivo). Our previous work described an in vitro tricompartmental ocular flow cell (TOFC) simulating the anterior and posterior cavities of the human eye. Based on promising preliminary results, in this study, a collagen scaffold enriched with human retinal pigmented epithelial cells (ARPE-19) was developed and introduced into the TOFC to partially mimic the human retina. Cells were cultured under dynamic flow conditions to emulate the posterior segment of the human eye. Bevacizumab was then injected into the central compartment of the TOFC to treat ARPE-19 cells and assess its effects. The results showed an absence of cytotoxic activity and a significant reduction in VEGF fluorescent signal, underscoring the potential of this in vitro model as a platform for researching new ophthalmic formulations addressing the posterior eye segment, eventually decreasing the need for animal testing.

Ultrasound boosts doxorubicin efficacy against sensitive and resistant ovarian cancer cells.

Ovarian cancer (OC) is characterised by the highest mortality of all gynaecological malignancies, frequent relapses, and the development of resistance to drug therapy. Sonodynamic therapy (SDT) is an innovative anticancer approach that combines a chemical/drug (sonosensitizer) with low-intensity ultrasound (US), which are both harmless per sé, with the sonosensitizer being acoustically activated, thus yielding localized cytotoxicity often via reactive oxygen species (ROS) generation. Doxorubicin (Doxo) is a potent chemotherapeutic drug that has also been recommended as a first-line treatment against OC. This research work aims to investigate whether Doxo can be used at very low concentrations, in order to avoid its significant side effects, as a sonosensitiser under US exposure to promote cancer cell death in Doxo non-resistant (A2780/WT) and Doxo resistant (A2780/ADR) human OC cell lines. Moreover, since recurrence is an important issue in OC, we have also investigated whether the proposed SDT with Doxo induces immunogenic cell death (ICD) and thus hinders OC recurrence. Our results show that the sonodynamic anticancer approach with Doxo is effective in both A2780/WT and A2780/ADR cell lines, and that it proceeds via a ROS-dependent mechanism of action and immune sensitization that is based on the activation of the ICD pathway.

Surface Functionalised Parenteral Nanoemulsions for Active and Homotypic Targeting to Melanoma.

Despite recent progressions in cancer genomic and immunotherapies, advanced melanoma still represents a life threat, pushing to optimise new targeted nanotechnology approaches for specific drug delivery to the tumour. To this aim, owing to their biocompatibility and favourable technological features, injectable lipid nanoemulsions were functionalised with proteins owing to two alternative approaches: transferrin was chemically grafted for active targeting, while cancer cell membrane fragments wrapping was used for homotypic targeting. In both cases, protein functionalisation was successfully achieved. Targeting efficiency was preliminarily evaluated using flow cytometry internalisation studies in two-dimensional cellular models, after fluorescence labelling of formulations with 6-coumarin. The uptake of cell-membrane-fragment-wrapped nanoemulsions was higher compared to uncoated nanoemulsions. Instead, the effect of transferrin grafting was less evident in serum-enriched medium, since such ligand probably undergoes competition with the endogenous protein. Moreover, a more pronounced internalisation was achieved when a pegylated heterodimer was employed for conjugation (p < 0.05).

Exploiting Shock Waves to Trigger the Anticancer Sonodynamic Activity of 5-Aminolevulinc Acid-Derived Protoporphyrin IX on In Vitro 2D and 3D Cancer Models.

Sonodynamic therapy (SDT) is a noninvasive method for cancer treatment based on selective activation of a sonosensitiser by ultrasound (US), which results in the generation of reactive oxygen species (ROS) and cancer cell death. SDT uses a similar approach to photodynamic therapy (PDT), but can overcome the main drawback of PDT, i.e., poor tissue penetration of light. This research work investigated the anticancer effect of SDT on various two- (2D) and three-dimensional (3D) in vitro tumour models, using PDT as a reference treatment. Sonodynamic experiments were performed with pulsed US, specifically with shock waves (SW) and the prodrug 5-aminolevulinic acid (Ala), which is converted-at the mitochondrial level-into the sonosensitiser protoporphyrin IX (PPIX). SW-mediated PPIX sonodynamic activation resulted in a significant decrease in cell proliferation, especially on human fibrosarcoma (HT-1080) cells, where PPIX accumulation was higher compared to human melanoma (A2058) and neuroblastoma (SH-SY5 Y) cells. Moreover, SW-mediated SDT showed significant ROS generation, cell line-dependent in its amount, probably due to differences in Ala-induced PPIX synthesis. In all cancer cell lines, apoptosis was highlighted as the main cancer cell death pathway determined by SW-mediated SDT, along with significant cytochrome c release, and a consequent increase in DNA damage. The efficacy of SDT with SW and Ala in halting cancer cell proliferation was also confirmed in 3D cancer spheroids. The present study suggests that SW-mediated SDT is a valuable approach to slow down tumour proliferation, thus opening an innovative scenario in cancer treatment.

The promising interplay between sonodynamic therapy and nanomedicine.

Sonodynamic therapy (SDT) is a non-invasive approach for cancer treatment in which chemical compounds, named sonosensitizers, are activated by non-thermal ultrasound (US), able to deeply penetrate into the tissues. Despite increasing interest, the underlying mechanisms by which US triggers the sonosensitizer therapeutic activity are not yet clearly elucidate, slowing down SDT clinical application. In this review we will discuss the main mechanisms involved in SDT with particular attention to the sonosensitizers involved for each described mechanism, in order to highlight how much important are the physicochemical properties of the sonosensitizers and their cellular localization to predict their bioeffects. Moreover, we will also focus our attention on the pivotal role of nanomedicine providing the sonodynamic anticancer approach with the ability to shape US-responsive agents to enhance specific sonodynamic effects as the sonoluminescence-mediated anticancer effects. Indeed, SDT is one of the biomedical fields that has significantly improved in recent years due to the increased knowledge of nanosized materials. The shift of the nanosystem from a delivery system for a therapeutic agent to a therapeutic agent in itself represents a real breakthrough in the development of SDT. In doing so, we have also highlighted potential areas in this field, where substantial improvements may provide a valid SDT implementation as a cancer therapy.

Ultrasound Triggers Hypericin Activation Leading to Multifaceted Anticancer Activity.

The use of ultrasound (US) in combination with a responsive chemical agent (sonosensitizer) can selectively trigger the agent's anticancer activity in a process called sonodynamic therapy (SDT). SDT shares some properties with photodynamic therapy (PDT), which has been clinically approved, but sets itself apart because of its use of US rather than light to achieve better tissue penetration. SDT provides anticancer effects mainly via the sonosensitizer-mediated generation of reactive oxygen species (ROS), although the precise nature of the underpinning mechanism is still under debate. This work investigates the SDT anticancer activity of hypericin (Hyp) in vitro in two- (2D) and three-dimensional (3D) HT-29 colon cancer models, and uses PDT as a yardstick due to its well-known Hyp phototoxicity. The cancer cell uptake and cellular localization of Hyp were investigated first to determine the proper noncytotoxic concentration and incubation time of Hyp for SDT. Furthermore, ROS production, cell proliferation, and cell death were evaluated after Hyp was exposed to US. Since cancer relapse and transporter-mediated multidrug resistance (MDR) are important causes of cancer treatment failure, the US-mediated ability of Hyp to elicit immunogenic cell death (ICD) and overcome MDR was also investigated. SDT showed strong ROS-mediated anticancer activity 48 h after treatment in both the HT-29 models. Specific damage-associated molecular patterns that are consistent with ICD, such as calreticulin (CRT) exposure and high-mobility group box 1 protein (HMGB1) release, were observed after SDT with Hyp. Moreover, the expression of the ABC transporter, P-glycoprotein (P-gp), in HT-29/MDR cells was not able to hinder cancer cell responsiveness to SDT with Hyp. This work reveals, for the first time, the US responsiveness of Hyp with significant anticancer activity being displayed, making it a full-fledged sonosensitizer for the SDT of cancer.

Formulation of curcumin-loaded solid lipid nanoparticles produced by fatty acids coacervation technique.

Curcumin (CU) loaded solid lipid nanoparticles (SLNs) of fatty acids (FA) were prepared with a coacervation technique based on FA precipitation from their sodium salt micelles in the presence of polymeric non-ionic surfactants. Myristic, palmitic, stearic, and behenic acids, and different polymers with various molecular weights and hydrolysis grades were employed as lipid matrixes and stabilisers, respectively. Generally, spherical-shaped nanoparticles with mean diameters below 500 nm were obtained, and using only middle-high hydrolysis, grade-polymer SLNs with diameters lower than 300 nm were produced. CU encapsulation efficiency was in the range 28-81% and highly influenced by both FA and polymer type. Chitosan hydrochloride was added to FA SLN formulations to produce bioadhesive, positively charged nanoparticles. A CU-chitosan complex formation could be hypothesised by DSC analysis, UV-vis spectra and chitosan surface tension determination. A preliminary study on HCT-116 colon cancer cells was developed to evaluate the influence of CU-loaded FA SLNs on cell viability.

The Effective Combination between 3D Cancer Models and Stimuli-Responsive Nanoscale Drug Delivery Systems.

Stimuli-responsive drug-delivery systems (DDSs) have emerged as a potential tool for applications in healthcare, mainly in the treatment of cancer where versatile nanocarriers are co-triggered by endogenous and exogenous stimuli. Two-dimensional (2D) cell cultures are the most important in vitro model used to evaluate the anticancer activity of these stimuli-responsive DDSs due to their easy manipulation and versatility. However, some limitations suggest that these in vitro models poorly predict the outcome of in vivo studies. One of the main drawbacks of 2D cell cultures is their inadequate representation of the 3D environment's physiological complexity, which sees cells interact with each other and the extracellular matrix (ECM) according to their specific cellular organization. In this regard, 3D cancer models are a promising approach that can overcome the main shortcomings of 2D cancer cell cultures, as these in vitro models possess many peculiarities by which they mimic in vivo tumors, including physiologically relevant cell-cell and cell-ECM interactions. This is, in our opinion, even more relevant when a stimuli-responsive DDS is being investigated. In this review, we therefore report and discuss endogenous and exogenous stimuli-responsive DDSs whose effectiveness has been tested using 3D cancer cell cultures.

5-Aminolevulinic Acid Triggered by Ultrasound Halts Tumor Proliferation in a Syngeneic Model of Breast Cancer.

Sonodynamic therapy is a bimodal therapeutic approach in which a chemical compound and ultrasound (US) synergistically act to elicit oxidative damage, triggering cancer cell death. Despite encouraging results, mainly for anticancer treatment, sonodynamics is still far from having a clinical application. Therefore, to close the gap between the bench and bedside, more in vivo studies are needed. In this investigation, the combined effect of 5-aminolevulinic acid (Ala), a natural porphyrin precursor, plus exposure to US, was investigated in vivo on a syngeneic breast cancer model. Real-time RT-PCR, Western blotting, and immunohistochemistry assays were performed to evaluate the effect of sonodynamic treatment on the main cancer hallmarks. The sonodynamic-treated group had a significant reduction (p ≤ 0.0001) in tumor size compared to the untreated group, and the Ala- and US-only treated groups, where a strong decrease (p ≤ 0.0001) in Ki67 protein expression was the most relevant feature of sonodynamic-treated cancer tissues. Moreover, oxidative stress was confirmed as the pivotal driver of the anticancer effect through cell cycle arrest, apoptosis, and autophagy; thus, sonodynamics should be explored further for cancer treatment.

Sonodynamic Treatment Induces Selective Killing of Cancer Cells in an In Vitro Co-Culture Model.

Sonodynamic Therapy (SDT) is a new anticancer strategy based on ultrasound (US) technique and is derived from photodynamic therapy (PDT); SDT is still, however, far from clinical application. In order to move this therapy forward from bench to bedside, investigations have been focused on treatment selectivity between cancer cells and normal cells. As a result, the effects of the porphyrin activation by SDT on cancer (HT-29) and normal (HDF 106-05) cells were studied in a co-culture evaluating cell cytotoxicity, reactive oxygen species (ROS) production, mitochondrial function and plasma membrane fluidity according to the bilayer sonophore (BLS) theory. While PDT induced similar effects on both HT-29 and HDF 106-05 cells in co-culture, SDT elicited significant cytotoxicity, ROS production and mitochondrial impairment on HT-29 cells only, whereas HDF 106-05 cells were unaffected. Notably, HT-29 and HDF 106-05 showed different cell membrane fluidity during US exposure. In conclusion, our data demonstrate a marked difference between cancer cells and normal cells in co-culture in term of responsiveness to SDT, suggesting that this different behavior can be ascribed to diversity in plasma membrane properties, such as membrane fluidity, according to the BLS theory.

Early impact of donor CYP3A5 genotype and Graft-to-Recipient Weight Ratio on tacrolimus pharmacokinetics in pediatric liver transplant patients.

Tacrolimus (TAC) pharmacokinetics is influenced by the donor CYP3A5 genotype and the age of pediatric liver recipients. However, an optimization of a genotype-based algorithm for determining TAC starting is needed to earlier achieve stable target levels. As the graft itself is responsible for its metabolism, the Graft-to-Recipient Weight Ratio (GRWR) might play a role in TAC dose requirements. A single-center study was carried out in a cohort of 49 pediatric recipients to analyse the impact of patient and graft characteristics on TAC pharmacokinetics during the first 15 post-transplant days. Children < 2 years received grafts with a significantly higher GRWR (4.2%) than children between 2-8 (2.6%) and over 8 (2.7%). TAC concentration/weight-adjusted dose ratio was significantly lower in recipients from CYP3A5*1/*3 donors or with extra-large (GRWR > 5%) or large (GRWR 3-5%) grafts. The donor CYP3A5 genotype and GRWR were the only significant predictors of the TAC weight adjusted doses. Patients with a GRWR > 4% had a higher risk of acute rejection, observed in 20/49 (41%) patients. In conclusion, TAC starting dose could be guided according to the donor CYP3A5 genotype and GRWR, allowing for a quicker achievement of target concentrations and eventually reducing the risk of rejection.