Identification and functional characterization of ASK/Dbf4, a novel cell survival gene in cutaneous melanoma with prognostic relevance

Malignant melanoma is one of the most aggressive and invasive metastatic tumors derived from melanocytes that have undergone malignant transformation by acquisition of genetic and epigenetic alterations. Oligonucleotide microarray-based screening of distinct stages in the tumor progression model of cutaneous melanoma identified ASK/Dbf4, as a novel determinant for melanoma development. Quantitative real-time polymerase chain reaction-based confirmation of ASK/Dbf4 on a series of benign nevi, dysplastic nevi, primary cutaneous melanomas and cutaneous melanoma metastases; and a number of other controls using normal human melanocytes as calibrator not only revealed a melanoma-specific over-expression but also revealed that higher ASK/Dbf4-expressing melanomas were associated with lower relapse-free survival. Additionally, we also confirmed the observed over-expression of ASK/Dbf4 in melanoma using western blot analysis and immunohistochemistry. As ASK/Dbf4 is known to be a cyclin-like regulatory subunit of mammalian Cdc7 from the studies in yeast, the present study investigated its role in melanoma cells. In keeping with its expected role, our data suggest that up-regulated ASK/Dbf4 is localized in the nucleus and binds to human Cdc7 to form Cdc7-ASK/Dbf4 complexes in several analyzed melanoma cell lines. Further, we demonstrate that small interfering RNA-mediated depletion of ASK/Dbf4 retarded melanoma cell survival and proliferation. In summary, we report the differential regulation of a novel gene, namely ASK/Dbf4, in melanoma and suggest that up-regulation of ASK/Dbf4 is a novel molecular determinant with prognostic relevance that confers a proliferative advantage in cutaneous melanoma.     

Multiple Familial Trichoepithelioma with Malignant Transformation

Trichoepithelioma (TE) is a benign tumor of follicular origin that presents as small, skin-colored papules predominantly on the face. When more than one family member is affected, the disease is known as multiple familial trichoepithelioma (MFT). It is a rare autosomal dominant (AD) skin disease. Malignant transformation is very rare. We present a case of MFT in a female patient and her father with malignant transformation to basal cell carcinoma (BCC) in the father. We summarized the main histological differential parameters between TE and BCC and applied immunophenotyping for both by administration of Bcl2, CD34, CD10 and androgen receptor (AR) antibodies.     

Genome‐wide single nucleotide polymorphism‐based autozygosity mapping facilitates identification of mutations in consanguineous families with epidermolysis bullosa

Autozygosity mapping (AM) is a technique utilised for mapping homozygous autosomal recessive (AR) traits and facilitation of genetic diagnosis. We investigated the utility of AM for the molecular diagnosis of heterogeneous AR disorders, using epidermolysis bullosa (EB) as a paradigm. We applied this technique to a cohort of 46 distinct EB families using both short tandem repeat (STR) and genome‐wide single nucleotide polymorphism (SNP) array‐based AM to guide targeted Sanger sequencing of EB candidate genes. Initially, 39 of the 46 cases were diagnosed with homozygous mutations using this method. Independently, 26 cases, including the seven initially unresolved cases, were analysed with an EB‐targeted next‐generation sequencing (NGS) panel. NGS identified mutations in five additional cases, initially undiagnosed due to the presence of compound heterozygosity, deep intronic mutations or runs of homozygosity below the set threshold of 2 Mb, for a total yield of 44 of 46 cases (95.7%) diagnosed genetically.     

Pre-treatment or post-treatment with hydroxychloroquine demonstrates neuroprotective effects in cerebral ischemia/reperfusion

Stroke is a serious life-threatening medical condition and is one of the principal reasons for death and disabilities worldwide. The aim of the present study was to determine the neuroprotective effects of hydroxychloroquine (HCQ) and the timing of its administration in cerebral ischemia/reperfusion (I/R) in rats. A global I/R model was used, and HCQ was administered in either pre- or post-treatment doses of 25 and 50 mg/kg. Effects of HCQ on infarct size, histological changes, oxidative stress, and learning and memory were evaluated. Phospho-AMPK and SQSTM1/p62 protein levels were also measured to elucidate the possible mechanisms involved. HCQ in both pre- (at doses of 25 and 50 mg/kg) or post-treatment (at a dose of 50 mg/kg) protocols reduces brain infarct size and histopathological changes and improves learning and memory after cerebral I/R. Pre-treatment with HCQ reduced AMPK activity with no significant effect on SQSTM1/p62 increment. Post-treatment with HCQ increased AMPK activity and SQSTM1/p62 protein levels. Our results show the neuroprotective effects of HCQ on cerebral I/R through the reduction in infarct size, histopathological changes, and improvement in memory and learning functions. Moreover, AMPK and autophagy may play a role in this protective effect.     

Systematic review of the diagnosis and management of necrotising otitis externa: Highlighting the need for high-quality research

Objectives

To present a systematic review and critical analysis of clinical studies for necrotising otitis externa (NOE), with the aim of informing best practice for diagnosis and management.

Design

Medline, Embase, Cochrane Library and Web of Science were searched from database inception until 30 April 2021 for all clinical articles on NOE. The review was registered on PROSPERO (ID: CRD42020128957) and conducted in accordance with PRISMA guidelines.

Results

Seventy articles, including 2274 patients were included in the final synthesis. Seventy-three percent were retrospective case series; the remainder were of low methodological quality. Case definitions varied widely. Median patient age was 69.2 years; 68% were male, 84% had diabetes and 10% had no reported immunosuppressive risk factor. Otalgia was almost universal (96%), with granulation (69%) and oedema (76%) the commonest signs reported. Pseudomonas aeruginosa was isolated in 62%, but a range of bacterial and fungal pathogens were reported and 14% grew no organism. Optimal imaging modality for diagnosis or follow-up was unclear. Median antimicrobial therapy duration was 7.2 weeks, with no definitive evidence for optimal regimens. Twenty-one percent had surgery with widely variable timing, indication, or procedure. One-year disease-specific mortality was 2%; treatment failure and relapse rates were 22% and 7%, respectively.

Conclusion

There is a lack of robust, high-quality data to support best practice for diagnosis and management for this neglected condition. A minimum set of reporting requirements is proposed for future studies. A consensus case definition is urgently needed to facilitate high-quality research.     

Defibrillation strategies for refractory ventricular fibrillation out-of-hospital cardiac arrest: A systematic review and network meta-analysis

Background and Objective

Double sequential external defibrillation (DSED) and vector-change defibrillation (VCD) have been suggested to enhance clinical outcomes for patients with ventricular fibrillation (VF) refractory of standard defibrillation (SD). Therefore, this network meta-analysis aims to evaluate the comparative efficacy of DSED, VCD, and SD for refractory VF.

Methods

A systematic review and network meta-analysis synthesizing randomized controlled trials (RCTs) and comparative observational studies retrieved from PubMed, EMBASE, WOS, SCOPUS, and Cochrane through November 15th, 2022. R software netmeta and netrank package (R version 4.2.0) and meta-insight software were used to pool dichotomous outcomes using odds ratio (OR) presented with the corresponding confidence interval (CI). Our protocol was prospectively published in PROSPERO with ID: CRD42022378533 .

Results

We included seven studies with a total of 1632 participants. DSED was similar to SD in survival to hospital discharge (OR: 1.14 with 95% CI [0.55, 2.83]), favorable neurological outcome (modified Rankin scale ≤2 or cerebral performance category ≤2) (OR: 1.35 with 95% CI [0.46, 3.99]), and return of spontaneous circulation (ROSC) (OR: 0.81 with 95% CI [0.43; 1.5]). In addition, VCD was similar to SD in survival to hospital discharge (OR: 1.12 with 95% CI [0.27, 4.57]), favorable neurological outcome (OR: 1.01 with 95% CI [0.18, 5.75]), and ROSC (OR: 0.88 with 95% CI [0.24; 3.15]).

Conclusion

Double sequential external defibrillation and VCD were not associated with enhanced outcomes in patients with refractory VF out-of-hospital cardiac arrest, compared to SD. However, the current evidence is still inconclusive, warranting further large-scale RCTs.