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A rigorous high-quality sequencing strategy was used to sequence the entire mitochondrial genome in macrodissected prostate cancer tissue and distant benign cells and analyze frequency and nature of somatic mtDNA mutations and their suitability for monitoring malignant transformation, tumor progression and metastasis. The somatic mutations in transfer RNAs (tRNAs) was found to be associated with elevated prostate specific antigen (PSA) levels, and the degree of heteroplasmy increased with increasing tumor activity and hence somatic mutations in the mitochondrial genome are frequent events in prostate cancer.

Abstract: The constitutive criterion for the evolutionary successful clade of ecdysozoans is a protective exoskeleton. In insects the exoskeleton, the so-called cuticle consists of three functional layers, the waterproof envelope, the proteinaceous epicuticle and the chitinous procuticle that are produced as an extracellular matrix by the underlying epidermal cells. Here, we present our electron-microscopic study of cuticle differentiation during embryogenesis in the fruit fly Drosophila melanogaster. We conclude that cuticle differentiation in the Drosophila embryo occurs in three phases. In the first phase, the layers are established. Interestingly, we find that establishment of the layers occurs partially simultaneously rather than in a strict sequential manner as previously proposed. In the second phase the cuticle thickens. Finally, in the third phase, when secretion of cuticle material has ceased, the chitin laminae acquire their typical orientation, and the epicuticle of the denticles and the head skeleton darken. Our work will help to understand the phenotypes of embryos mutant for genes encoding essential cuticle factors, in turn revealing mechanisms of cuticle differentiation. [Copyright &y& Elsevier]