Chitosan Ascorbate Nanoparticles for the Vaginal Delivery of Antibiotic Drugs in Atrophic Vaginitis.

The aim of the present work was the development of chitosan ascorbate nanoparticles (CSA NPs) loaded into a fast-dissolving matrix for the delivery of antibiotic drugs in the treatment of atrophic vaginitis. CSA NPs loaded with amoxicillin trihydrate (AX) were obtained by ionotropic gelation in the presence of pentasodium tripolyphosphate (TPP). Different CSA:TPP and CSA:AX weight ratios were considered and their influence on the particle size, polydispersion index and production yield were investigated. CSA NPs were characterized for mucoadhesive, wound healing and antimicrobial properties. Subsequently, CSA NPs were loaded in polymeric matrices, whose composition was optimized using a DoE (Design of Experiments) approach (simplex centroid design). Matrices were obtained by freeze-drying aqueous solutions of three hydrophilic excipients, polyvinylpirrolidone, mannitol and glycin. They should possess a mechanical resistance suitable for the administration into the vaginal cavity and should readily dissolve in the vaginal fluid. In addition to antioxidant properties, due to the presence of ascorbic acid, CSA NPs showed in vitro mucoadhesive, wound healing and antimicrobial properties. In particular, nanoparticles were characterized by an improved antimicrobial activity with respect to a chitosan solution, prepared at the same concentration. The optimized matrix was characterized by mechanical resistance and by the fast release in simulated vaginal fluid of nanoparticles characterized by unchanged size.

Impact of CYP19A1 and ESR1 variants on early-onset side effects during combined endocrine therapy in the TEXT trial.

BACKGROUND: Single nucleotide polymorphisms (SNPs) in the estrogen receptor 1 (ESR1) and cytochrome P450 19A1 (CYP19A1) genes have been associated with breast cancer risk, endocrine therapy response and side effects, mainly in postmenopausal women with early breast cancer. This analysis aimed to assess the association of selected germline CYP19A1 and ESR1 SNPs with early-onset hot flashes, sweating and musculoskeletal symptoms in premenopausal patients enrolled in the Tamoxifen and Exemestane Trial (TEXT). METHODS: Blood was collected from consenting premenopausal women with hormone-responsive early breast cancer, randomly assigned to 5-years of tamoxifen plus ovarian suppression (OFS) or exemestane plus OFS. DNA was extracted with QIAamp kits and genotyped for two CYP19A1 (rs4646 and rs10046) and three ESR1 (rs2077647, rs2234693 and rs9340799) SNPs by a real-time pyrosequencing technique. Adverse events (AEs) were recorded at baseline and 3-monthly during the first year. Associations of the genotype variants with grade ≥2 early-onset targeted AEs of hot flashes/sweating or musculoskeletal events were assessed using logistic regression models. RESULTS: There were 2660 premenopausal patients with breast cancer in the intention-to-treat population of TEXT, and 1967 (74 %) are included in this translational study. The CYP19A1 rs10046 variant T/T, represented in 23 % of women, was associated with a reduced incidence of grade ≥2 hot flashes/sweating (univariate odds ratio (OR) = 0.78; 95 % CI 0.63-0.97; P = 0.03), more strongly in patients assigned exemestane + OFS (TT vs CT/CC: OR = 0.65, 95 % CI = 0.48-0.89) than assigned tamoxifen + OFS (OR = 0.94, 95 % CI = 0.69-1.27, interaction P = 0.03). No association with any of the CYP19A1/ESR1 genotypes and musculoskeletal AEs was found. CONCLUSION: The CYP19A1 rs10046 variant T/T favors lower incidence of hot flashes/sweating under exemestane + OFS treatment, suggesting endocrine-mediated effects. Based on findings from others, this SNP may potentially enhance treatment adherence and treatment efficacy. We plan to evaluate the clinical impact of this polymorphism during time, pending sufficient median follow up. TRIAL REGISTRATION: ClinicalTrials.gov NCT00066703, registered August 6, 2003.

A Presurgical Study of Oral Silybin-Phosphatidylcholine in Patients with Early Breast Cancer.

Silybin-phosphatidylcholine is an orally bioavailable complex of silybin, a polyphenolic flavonolignan derived from milk thistle, endowed with potential anticancer activity in preclinical models. The purpose of this window of opportunity trial was to determine, for the first time in early breast cancer patients, the breast tissue distribution of silybin. Twelve breast cancer patients received silybin-phosphatidylcholine, 2.8 g daily for 4 weeks prior to surgery. Silybin levels were measured before (SIL) and after (TOT-SIL) enzymatic hydrolysis by high-performance liquid chromatography (HPLC)-MS/MS in biologic samples (plasma, urine, breast cancer, and surrounding normal tissue). Fasting blood samples were taken at baseline, before the last administration, and 2 hours later. All patients were fully compliant and completed the treatment program. No toxicity was observed. SIL and TOT-SIL were undetectable in baseline samples. Despite a high between-subject variability, repeated administration of Siliphos achieved levels of TOT-SIL of 31,121 to 7,654 ng/mL in the plasma and up to 1,375 ng/g in breast cancer tissue. SIL concentrations ranged from 10,861 to 1,818 ng/mL in plasma and up to 177 ng/g in breast cancer tissue. Median TOT-SIL concentration was higher in the tumor as compared with the adjacent normal tissue (P = 0.018). No significant change in either blood levels of IGF-I and nitric oxide or Ki-67 in tumors was noted. Silybin-phosphatidylcholine, taken orally, can deliver high blood concentrations of silybin, which selectively accumulates in breast tumor tissue. These findings provide the basis for a future phase II biomarker trial in breast cancer prevention.

Comparison of poloxamer- and chitosan-based thermally sensitive gels for the treatment of vaginal mucositis.

CONTEXT: The local treatment of vaginal mucositis requires an intimate and prolonged contact of anti-infective drugs with the mucosa. This can be achieved by means of mucoadhesive and thermally sensitive vehicles, capable of gelifying at the physiological temperature. OBJECTIVE: The aim of the present work was to compare the potentiality of poloxamer 407 (PLX)/chitosan lactate (CS-L) and CS-L/glycerophosphate (GP) mixtures as mucoadhesive thermally sensitive vehicles for the treatment of vaginal mucositis. MATERIALS AND METHODS: PLX/CS-L and CS-L/GP mixtures were characterized for gelation and mucoadhesion properties as well as for bioactive (antimicrobial and wound healing) properties. Finally, the mixtures were loaded with amoxicillin trihydrate as model drug and characterized for drug release and washability properties. RESULTS AND DISCUSSION: The addition of CS-L to PLX causes an increase in PLX gelation temperature from 30 °C to the physiological temperature. The dilution with simulated vaginal fluid causes an increase in gelation time of PLX/CS-L mixture, while no variation of such parameter is observed for CS-L/GP mixture which is nevertheless characterized by poorer elastic properties. The stronger mucoadhesion properties of CS-L/GP mixture counterbalance the poorer elasticity of the gel and are responsible for a longer drug contact with the biological substrate. CS-L/GP mixture is moreover characterized by better bioactive properties than PLX-based mixture. CONCLUSION: CS-L/GP mixture represents a promising thermally sensitive vehicle.

Circulating hormones and breast cancer risk in premenopausal women: a randomized trial of low-dose tamoxifen and fenretinide.

Tamoxifen and fenretinide have been extensively studied and exhibit breast cancer-preventing activity. We aimed to assess their effect on sex hormones, sex hormone binding globulin (SHBG) and retinol, and their association with mammographic density (MD) and breast cancer events. In a double-blind, placebo-controlled trial, premenopausal women at risk for breast cancer were randomized to tamoxifen 5 mg/day, fenretinide, both agents, or placebo for 2 years. We measured MD and circulating concentrations of follicle-stimulating hormone, luteinizing hormone (LH), estradiol, progesterone, testosterone, androstenedione, dehydro-epiandrosteronesulfate, prolactin, SHBG, and retinol at baseline and on yearly intervals. The associations with breast cancer events were evaluated through competing risk and Cox regression survival models. Low-dose tamoxifen markedly and enduringly increased SHBG, whereas the increases in testosterone, estradiol, and prolactin and reduction in LH weakened after 1 year. Fenretinide increased testosterone and androstenedione and decreased retinol. MD correlated directly with SHBG and inversely with retinol. After a median follow-up of 12 years, the 10-year cumulative incidence of breast cancer events was 37 % in women with SHBG ≤ 59.3 nmol/L, 22 % in women with SHBG between 59.3 and 101 nmol/L, and 19 % in women with SHBG > 101 nmol/L (P = 0.018). The difference among SHBG tertiles remained statistically significant at multivariable analysis: HR = 2.26 (95 % CI 1.04, 4.89) for the lowest versus the highest tertile. We conclude that low-dose tamoxifen or fenretinide exhibits favorable hormonal profiles as single agents, further supporting their administration for prevention of breast cancer in premenopause. Notably, SHBG levels were inversely associated with breast neoplastic events.

Development of sponge-like dressings for mucosal/transmucosal drug delivery into vaginal cavity.

The aim of the present work was the development of vaginal sponge-like dressings based on chitosan ascorbate (CS) and on hyaluronic acid sodium salt/lysine acetate (HAS) combination. Sponge-like dressings were prepared by freeze-drying and characterized for mechanical resistance and mucoadhesion. CS dressings show higher mechanical and mucoadhesion properties in comparison with HAS dressing. The enzymatic inhibition properties of the dressings were evaluated in vitro against carboxipeptidase A in view of their employment for vaginal delivery of peptidic drugs. All the dressings were able to inhibit carboxipeptidase activity; CS dressings, independently of polymer MW, completely inhibited enzyme activity. Release and penetration enhancement properties of the dressings loaded with a high molecular weight hydrophilic molecule, fluorescein isothiocyanate dextran (FD4), were assessed. CS dressings were able to prolong FD4 release. All the dressings showed penetration enhancement properties into pig vaginal mucosa although to a different extent: greater for dressings based on CS than for that containing HAS. Moreover, CS dressings demonstrated intrinsic antimicrobial properties. The suitability of sponge-like systems for the treatment of vaginal infections was assessed by loading the CS dressing characterized by the best mechanical and antimicrobial properties with an antibiotic drug (clyndamicin-2-phosphate) and by checking drug release.