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The singular BRCA1/2 mutational landscape of Asturias is updated 10 years after the first study. We analyzed BRCA1 and BRCA2 pathogenic variants in 1653 index cases. In total, 238 families were identified to carry a pathogenic variant, 163 families in BRCA1 and 75 families in BRCA2. This yielded a prevalence rate of 14.4%. Seven recurrent variants were found accounting for 55% of the cases. Among them, three are widely distributed (BRCA1 c.211A>G, c.470_471del and c.3331_3334del) and four had been reported as novel in Asturias: two in BRCA1 (c.1674del and c.2901_2902dup) and two in BRCA2 (c.2095C>T and c.4040_4035delinsC). A common haplotype was established for all recurrent variants indicating a shared ancestral origin. Three splicing analyses are shown: BRCA1:c.5152+3A>C and BRCA1:c.5333‐3T>G that lead to skipping of exon 18, and 22 respectively, and BRCA1:c.5278‐1G>T giving rise to two transcripts, one lacking exon 21 (p.Ille1760Glyfs*60) and one lacking the first 8 nucleotides of exon 21 (p.Phe1761Asnfs*14), supporting pathogenicity for these variants. [ABSTRACT FROM AUTHOR]

The article discusses the impact of functionally relevant germline CD5 variants on the prognosis of chronic lymphocytic leukaemia (CLL). CD5 variants were found to have influenced the natural behavior of CLL cell biology and its outcome. CD5 signalling was also considered a relevant factor for the production of B1a cell autocrine growth factor interleukin 10.

MT1- MMP ( MMP14) is a collagenolytic enzyme located at the cell surface and implicated in extracellular matrix ( ECM) remodeling. Mmp14−/− mice present dwarfism, bone abnormalities, and premature death. We demonstrate herein that the loss of MT1- MMP also causes cardiac defects and severe metabolic changes, and alters the cytoskeleton and the nuclear lamina structure. Moreover, the absence of MT1- MMP induces a senescent phenotype characterized by up-regulation of p16 INK 4a and p21 CIP 1/ WAF 1, increased activity of senescence-associated β-galactosidase, generation of a senescence-associated secretory phenotype, and somatotroph axis alterations. Consistent with the role of retinoic acid signaling in nuclear lamina stabilization, treatment of Mmp14−/− mice with all- trans retinoic acid reversed the nuclear lamina alterations, partially rescued the cell senescence phenotypes, ameliorated the pathological defects in bone, skin, and heart, and extended their life span. These results demonstrate that nuclear architecture and cell senescence can be modulated by a membrane protease, in a process involving the ECM as a key regulator of nuclear stiffness under cell stress conditions. [ABSTRACT FROM AUTHOR]

Malignant peripheral nerve sheath tumors ( MPNSTs) are soft-tissue sarcomas that can arise either sporadically or in association with neurofibromatosis type 1 ( NF1). These aggressive malignancies confer poor survival, with no effective therapy available. We present the generation and characterization of five distinct MPNST orthoxenograft models for preclinical testing and personalized medicine. Four of the models are patient-derived tumor xenografts ( PDTX), two independent MPNSTs from the same NF1 patient and two from different sporadic patients. The fifth model is an orthoxenograft derived from an NF1-related MPNST cell line. All MPNST orthoxenografts were generated by tumor implantation, or cell line injection, next to the sciatic nerve of nude mice, and were perpetuated by 7-10 mouse-to-mouse passages. The models reliably recapitulate the histopathological properties of their parental primary tumors. They also mimic distal dissemination properties in mice. Human stroma was rapidly lost after MPNST engraftment and replaced by murine stroma, which facilitated genomic tumor characterization. Compatible with an origin in a catastrophic event and subsequent genome stabilization, MPNST contained highly altered genomes that remained remarkably stable in orthoxenograft establishment and along passages. Mutational frequency and type of somatic point mutations were highly variable among the different MPNSTs modeled, but very consistent when comparing primary tumors with matched orthoxenografts generated. Unsupervised cluster analysis and principal component analysis ( PCA) using an MPNST expression signature of ~1,000 genes grouped together all primary tumor-orthoxenograft pairs. Our work points to differences in the engraftment process of primary tumors compared with the engraftment of established cell lines. Following standardization and extensive characterization and validation, the orthoxenograft models were used for initial preclinical drug testing. Sorafenib (a BRAF inhibitor), in combination with doxorubicin or rapamycin, was found to be the most effective treatment for reducing MPNST growth. The development of genomically well-characterized preclinical models for MPNST allowed the evaluation of novel therapeutic strategies for personalized medicine. [ABSTRACT FROM AUTHOR]

Mutations in the nuclear envelope protein lamin A or in its processing protease ZMPSTE24 cause human accelerated aging syndromes, including Hutchinson-Gilford progeria syndrome. Similarly, Zmpste24-deficient mice accumulate unprocessed prelamin A and develop multiple progeroid symptoms, thus representing a valuable animal model for the study of these syndromes. Zmpste24-deficient mice also show marked transcriptional alterations associated with chromatin disorganization, but the molecular links between both processes are unknown. We report herein that Zmpste24-deficient mice show a hypermethylation of rDNA that reduces the transcription of ribosomal genes, being this reduction reversible upon treatment with DNA methyltransferase inhibitors. This alteration has been previously described during physiological aging in rodents, suggesting its potential role in the development of the progeroid phenotypes. We also show that Zmpste24-deficient mice present global hypoacetylation of histones H2B and H4. By using a combination of RNA sequencing and chromatin immunoprecipitation assays, we demonstrate that these histone modifications are associated with changes in the expression of several genes involved in the control of cell proliferation and metabolic processes, which may contribute to the plethora of progeroid symptoms exhibited by Zmpste24-deficient mice. The identification of these altered genes may help to clarify the molecular mechanisms underlying aging and progeroid syndromes as well as to define new targets for the treatment of these dramatic diseases. [ABSTRACT FROM AUTHOR]

Matrix metalloproteinases (MMPs) have been implicated in numerous tissue-remodeling processes. The finding that mice deficient in collagenase-2 (MMP-8) are more susceptible to develop skin cancer, prompted us to investigate the role of this protease in cutaneous wound healing. We have observed a significant delay in wound closure in MMP8-/- mice and an altered inflammatory response in their wounds, with a delay of neutrophil infiltration during the first days and a persistent inflammation at later time points. These changes were accompanied by alterations in the TGF-β1 signaling pathway and by an apoptosis defect in MMP8-/- mice. The delay in wound healing observed in MMP8-/- mice was rescued by bone marrow transplantation from wildtype mice. Analysis of other MMPs showed that MMP8-/-mice had a significant increase in the expression of MMP-9, suggesting that both proteases might act coordinately in this process. This possibility was further supported by the novel finding that MMP-8 and MMP-9 form specific complexes in vivo. Taken together, these data indicate that MMP-8 participates in wound repair by contributing to the resolution of inflammation and open the possibility to develop new strategies for treating wound healing defects. [ABSTRACT FROM AUTHOR]

Focal adhesion kinase (FAK) was first identified as a viral Src (v-Src) substrate, but the role of FAK in Src transformation events remains undefined. We show that stable expression of the FAK C-terminal domain (termed FRNK) in v-Src-transformed NIH 3T3 fibroblasts inhibited cell invasion through Matrigel and blocked experimental metastases in nude mice without effects on cell motility. FRNK inhibitory activity was dependent upon its focal contact localization. FRNK expression disrupted the formation of a v-Src-FAK signaling complex, inhibited p130Cas tyrosine phosphorylation, and attenuated v-Src-stimulated ERK and JNK kinase activation. However, FRNK did not affect v-Src-stimulated Akt activation, cell growth in soft agar, or subcutaneous tumor formation in nude mice. FRNK-expressing cells exhibited decreased matrix metalloproteinase-2 (MMP-2) mRNA levels and MMP-2 secretion. Transient FRNK expression in human 293 cells inhibited exogenous MMP-2 promoter activity and overexpression of wild-type but not catalytically-inactive (Ala-404) MMP-2 rescued v-Src- stimulated Matrigel invasion in the presence of FRNK. Our findings show the importance of FAK in Src-stimulated cell invasion and support a rote for Src-FAK signaling associated with elevated tumor cell metastases. [ABSTRACT FROM AUTHOR]

The only inhibitor of human salivary α-amylase identified so far in Hordeum has been isolated from barley cv. Bomi endosperm. This protein has the same N-terminal sequence (23 residues), molecular mass, and isoelectric point as one of the subunits of the barley tetrameric inhibitor previously characterized. However, enzymatic cleavage of both proteins with endoproteinase Glu-C revealed that they are products of different genes. The two isoforms have diverged in their aggregative and inhibitory properties. Thus, the subunit previously characterized forms, along with two other subunits, a tetramer active towards insect but not human salivary α-amylase, while the isoform reported here behaves as a homodimer effective against the human enzyme. These results are discussed in the context of the evolution of the cereal α-amylase inhibitor family. [ABSTRACT FROM AUTHOR]