Crown-Rump Length Measured in the Early First Trimester as a Predictor of Low Birth Weight

The aim of this study is to assess the association between crown-rump length (CRL) measured before the 10th gestational week and birth weight. Results from 316 transvaginal ultrasonography scans at the 46th, 53rd, 60th, 67th, and 74th days of pregnancy were compared in low birth weight (LBW) versus normal birth weight groups. A positive correlation between CRL and birth weight was observed when CRL was measured at days 60, 67, and 74. CRL measured on the 67th day of pregnancy was significantly smaller in the LBW group than in the normal birth weight group. A cut-off value of CRL=26.5 mm measured at day 67 has the highest power to predict LBW.     

Isolated foveal hypoplasia with secondary nystagmus and low vision is associated with a homozygous SLC38A8 mutation

Foveal hypoplasia, always accompanied by nystagmus, is found as part of the clinical spectrum of various eye disorders such as aniridia, albinism and achromatopsia. However, the molecular basis of isolated autosomal recessive foveal hypoplasia is yet unknown. Individuals of apparently unrelated non consanguineous Israeli families of Jewish Indian (Mumbai) ancestry presented with isolated foveal hypoplasia associated with congenital nystagmus and reduced visual acuity. Genome-wide homozygosity mapping followed by fine mapping defined a 830 Kb disease-associated locus (LOD score 3.5). Whole-exome sequencing identified a single missense mutation in the homozygosity region: c.95T>G, p.(Ile32Ser), in a conserved amino acid within the first predicted transmembrane domain of SLC38A8. The mutation fully segregated with the disease-associated phenotype, demonstrating an ∼10% carrier rate in Mumbai Jews. SLC38A8 encodes a putative sodium-dependent amino-acid/proton antiporter, which we showed to be expressed solely in the eye. Thus, a homozygous SLC38A8 mutation likely underlies isolated foveal hypoplasia.     

Targeting protein-trafficking pathways alters melanoma treatment sensitivity

Protein-trafficking pathways are targeted here in human melanoma cells using methods independent of oncogene mutational status, and the ability to up-regulate and down-regulate tumor treatment sensitivity is demonstrated. Sensitivity of melanoma cells to cis-diaminedichloroplatinum II (cDDP, cis-platin), carboplatin, dacarbazine, or temozolomide together with velaparib, an inhibitor of poly (ADP ribose) polymerase 1, is increased by up to 10-fold by targeting genes that regulate both protein trafficking and the formation of melanosomes, intracellular organelles unique to melanocytes and melanoma cells. Melanoma cells depleted of either of the protein-trafficking regulators vacuolar protein sorting 33A protein (VPS33A) or cappuccino protein (CNO) have increased nuclear localization of cDDP, increased nuclear DNA damage by platination, and increased apoptosis, resulting in increased treatment sensitivity. Depleted cells also exhibit a decreased proportion of intracellular, mature melanosomes compared with undepleted cells. Modulation of protein trafficking via cell-surface signaling by binding the melanocortin 1 receptor with the antagonist agouti-signaling protein decreased the proportion of mature melanosomes formed and increased cDDP sensitivity, whereas receptor binding with the agonist melanocyte-stimulating hormone resulted in an increased proportion of mature melanosomes formed and in decreased sensitivity (i.e., increased resistance) to cDDP. Mutation of the protein-trafficking gene Hps6, known to impair the formation of mature melanosomes, also increased cDDP sensitivity. Together, these results indicate that targeting protein-trafficking molecules markedly increases melanoma treatment sensitivity and influences the degree of melanosomes available for sequestration of therapeutic agents.     

Siah2‐deficient mice show impaired skin wound repair

Hypoxia is associated with the dermal wound healing process and hypoxia signaling is presumed to be crucial for normal wound repair. The Siah2 ubiquitin ligase controls the abundance of hypoxia‐inducible factor‐1 alpha, and loss of Siah2 results in destabilization of hypoxia‐inducible factor‐1 alpha under hypoxia. Utilizing Siah2^?/? mice we demonstrate that cutaneous wound healing is impaired in these mice. Wounds in Siah2^?/? mice heal slower and are associated with delayed induction of myofibroblast infiltration and reduced collagen deposition. This coincides with delayed angiogenesis and reduced macrophage infiltration into the wounds of Siah2^?/? mice. We furthermore demonstrate that primary Siah2^?/? dermal fibroblasts have reduced migratory capacities and produce less collagen than wild‐type fibroblasts. Additionally, Siah2^?/? fibroblasts showed conserved responses to transforming growth factor‐β at the receptor level (pSmad 2C activation) but reduced responses downstream. Together, our data show, for the first time, that Siah2 is involved as a positive regulator in the wound healing response. Understanding the role of hypoxia signaling in tissue repair and fibrosis and interference with the hypoxia signaling pathway via regulation of Siah2 may provide new targets for clinical regulation of fibrosis and scarring.