Identification of microRNAs associated with invasive and aggressive phenotype in cutaneous melanoma by next-generation sequencing.

A comprehensive repertoire of human microRNAs (miRNAs) that could be involved in early melanoma invasion into the dermis remains unknown. To this end, we sequenced small RNAs (18-30 nucleotides) isolated from an annotated series of invasive melanomas (average invasive depth, 2.0 mm), common melanocytic nevi, and matched normal skin (n=28). Our previously established bioinformatics pipeline identified 765 distinct mature known miRNAs and defined a set of top 40 list that clearly segregated melanomas into thin (0.75 mm) and thick (2.7 mm) groups. Among the top, miR-21-5p, let-7b-5p, let-7a-5p, miR-424-5p, miR-423-5p, miR-21-3p, miR-199b-5p, miR-182-5p, and miR-205-5p were differentially expressed between thin and thick melanomas. In a validation cohort (n=167), measured expression of miR-21-5p and miR-424-5p, not previously reported in melanoma, were significantly increased in invasive compared with in situ melanomas (P<0.0001). Increased miR-21-5p levels were significantly associated with invasive depth (P=0.038), tumor mitotic index (P=0.038), lymphovascular invasion (P=0.0036), and AJCC stage (P=0.038). In contrast, let-7b levels were significantly decreased in invasive and in situ melanomas compared with common and dysplastic nevi (P<0.0001). Decreased let-7b levels were significantly associated with invasive depth (P=0.011), Clark's level (P=0.013), ulceration (P=0.0043), and AJCC stage (P=0.011). These results define a distinct set of miRNAs associated with invasive and aggressive melanoma phenotype.

microRNA in situ hybridization for miR-211 detection as an ancillary test in melanoma diagnosis.

Some melanocytic tumors can be histologically ambiguous causing diagnostic difficulty, which could lead to overtreatment of benign lesions with an unwarranted psychological distress or undertreatment of malignant cancers. Previously, we demonstrated that significantly decreased miR-211 expression in melanomas compared with melanocytic nevi could accurately discriminate malignant from benign tumors. Herein we show microRNA in situ hybridization for fluorescent detection of miR-211, suitable for paraffin-embedded tissues in 109 primary melanocytic tumors. miR-211 expression was significantly lower in melanomas vs nevi (P<0.0001), and receiver operating characteristic curve (area under the curve=0.862) accurately discriminated melanomas from nevi with 90% sensitivity and 86.2% specificity. Qualitatively, all dysplastic nevi expressed miR-211 at high (86%) and low (14%) levels, independent of the degree of nuclear atypia. All 35 melanocytic tumors with Spitz morphology expressed miR-211 independent of morphological classification, where clinical follow-up of these patients showed no recurrence at the site or metastasis in mean and median of 3 (ranging 2-5) years. Moreover, a decision tree learning analysis selected age and miR-211 miRNA in situ hybridization as the predictive variables for benign or malignant outcome in 88 patients correctly classified 92% (81 out of 88) of cases as proven by receiver operating characteristic curve (area under the curve=0.9029). These results support miR-211 as a leading miRNA candidate for melanoma diagnosis and miRNA in situ hybridization as a uniquely uncomplicated ancillary test.

A novel miR-451a isomiR, associated with amelanotypic phenotype, acts as a tumor suppressor in melanoma by retarding cell migration and invasion.

miRNAs are key regulatory small non-coding RNAs involved in critical steps of melanoma tumorigenesis; however, the relationship between sequence specific variations at the 5' or 3' termini (isomiR) of a miRNA and cancer phenotype remains unclear. Deep-sequencing and qRT-PCR showed reduced expression of miR-144/451a cluster and most abundant isomiR (miR451a.1) in dysplastic nevi, in-situ and invasive melanomas compared to common nevi and normal skin (n = 101). miRNA in situ hybridization reproducibly confirmed lost miR-451a.1 in melanoma compared to nevus cells or adjacent keratinocytes. Significantly higher expression of miR-451a.1 was associated with amelanotic phenotype in melanomas (n = 47). In contrast, miR-451a was associated with melanotic phenotype, absent pagetoid scatter of intraepidermal melanocytes, superficial spreading histological subtype and tumor inflammation. Sequencing miRNAs from cultured melanocytes with cytoplasmic melanin gradient (light, medium to dark) showed absent miR-451a while revealing other melanin-associated miRNAs, e.g. miR-30b, miR-100 and miR-590 in darkly and let-7a, let-7i and let-7f in lightly to moderately pigmented cultured melanocytes. Ectopic expression of miR-144/451a in melanoma cell lines resulted in markedly higher levels of mature miR-451a.1 than miR451a or miR-144; and significantly retarded cell migration and inhibited invasion in a glucose-sensitive manner. Surprisingly, these effects were not mediated by calcium binding protein 39 (CAB39), a proven miR451a gene target. miR-144/miR-451a cluster is a novel miRNA locus with tumor suppressive activity in melanoma.

Reduction of Salmonella enterica serovar enteritidis colonization in 20-day-old broiler chickens by the plant-derived compounds trans-cinnamaldehyde and eugenol.

The efficacies of trans-cinnamaldehyde (TC) and eugenol (EG) for reducing Salmonella enterica serovar Enteritidis colonization in broiler chickens were investigated. In three experiments for each compound, 1-day-old chicks (n = 75/experiment) were randomly assigned to five treatment groups (n = 15/treatment group): negative control (-ve S. Enteritidis, -ve TC, or EG), compound control (-ve S. Enteritidis, +ve 0.75% [vol/wt] TC or 1% [vol/wt] EG), positive control (+ve S. Enteritidis, -ve TC, or EG), low-dose treatment (+ve S. Enteritidis, +ve 0.5% TC, or 0.75% EG), and high-dose treatment (+ve S. Enteritidis, +ve 0.75% TC, or 1% EG). On day 0, birds were tested for the presence of any inherent Salmonella (n = 5/experiment). On day 8, birds were inoculated with ∼8.0 log(10) CFU S. Enteritidis, and cecal colonization by S. Enteritidis was ascertained (n = 10 chicks/experiment) after 24 h (day 9). Six birds from each treatment group were euthanized on days 7 and 10 after inoculation, and cecal S. Enteritidis numbers were determined. TC at 0.5 or 0.75% and EG at 0.75 or 1% consistently reduced (P < 0.05) S. Enteritidis in the cecum (≥3 log(10) CFU/g) after 10 days of infection in all experiments. Feed intake and body weight were not different for TC treatments (P > 0.05); however, EG supplementation led to significantly lower (P < 0.05) body weights. Follow-up in vitro experiments revealed that the subinhibitory concentrations (SICs, the concentrations that did not inhibit Salmonella growth) of TC and EG reduced the motility and invasive abilities of S. Enteritidis and downregulated expression of the motility genes flhC and motA and invasion genes hilA, hilD, and invF. The results suggest that supplementation with TC and EG through feed can reduce S. Enteritidis colonization in chickens.

A Novel Vaccine Using Nanoparticle Platform to Present Immunogenic M2e against Avian Influenza Infection.

Using peptide nanoparticle technology, we have designed two novel vaccine constructs representing M2e in monomeric (Mono-M2e) and tetrameric (Tetra-M2e) forms. Groups of specific pathogen free (SPF) chickens were immunized intramuscularly with Mono-M2e or Tetra-M2e with and without an adjuvant. Two weeks after the second boost, chickens were challenged with 107.2 EID50 of H5N2 low pathogenicity avian influenza (LPAI) virus. M2e-specific antibody responses to each of the vaccine constructs were tested by ELISA. Vaccinated chickens exhibited increased M2e-specific IgG responses for each of the constructs as compared to a non-vaccinated group. However, the vaccine construct Tetra-M2e elicited a significantly higher antibody response when it was used with an adjuvant. On the other hand, virus neutralization assays indicated that immune protection is not by way of neutralizing antibodies. The level of protection was evaluated using quantitative real time PCR at 4, 6, and 8 days post-challenge with H5N2 LPAI by measuring virus shedding from trachea and cloaca. The Tetra-M2e with adjuvant offered statistically significant (P < 0.05) protection against subtype H5N2 LPAI by reduction of the AI virus shedding. The results suggest that the self-assembling polypeptide nanoparticle shows promise as a potential platform for a development of a vaccine against AI.

Unexpectedly high proportion of ancestral Manu genotype Mycobacterium tuberculosis strains cultured from tuberculosis patients in Egypt.

Tuberculosis is one of the important public health problems in Egypt. However, limited information on the Mycobacterium tuberculosis genotypes circulating in Egypt is available. A total of 151 M. tuberculosis strains were characterized by spoligotyping. The results revealed that 74.8% of M. tuberculosis isolates grouped into 13 different clusters, while 25.2% had unique spoligotype patterns. Comparison with an international spoligotyping database (the SITVIT2 database) showed that types SIT53 (T1 variant) and SIT54 (Manu2 variant) were the most common types between cluster groups. In addition, new shared types SIT2977, SIT2978, and SIT2979 were observed. The results identified for the first time an unusually high proportion of ancestral Manu strains of M. tuberculosis from patients in Egypt. The percentage of the Manu clade in this study (27.15%) was significantly higher than its overall representation of 0.4% in the SITVIT2 database. We show that in Egypt tuberculosis is caused by a predominant M. tuberculosis genotype belonging to the ancestral Manu lineage which could be a missing link in the split between ancestral and modern tubercle bacilli during the evolution of M. tuberculosis.