The overall understanding of the molecular etiologies of intellectual disability (ID) and developmental delay (DD) is increasing as next-generation sequencing technologies identify genetic variants in individuals with such disorders. However, detailed analyses conclusively confirming these variants, as well as the underlying molecular mechanisms explaining the diseases, are often lacking. Here, we report on an ID syndrome caused by de novo heterozygous loss-of-function (LoF) mutations in SON. The syndrome is characterized by ID and/or DD, malformations of the cerebral cortex, epilepsy, vision problems, musculoskeletal abnormalities, and congenital malformations. Knockdown of son in zebrafish resulted in severe malformation of the spine, brain, and eyes. Importantly, analyses of RNA from affected individuals revealed that genes critical for neuronal migration and cortex organization (TUBG1, FLNA, PNKP, WDR62, PSMD3, and HDAC6) and metabolism (PCK2, PFKL, IDH2, ACY1, and ADA) are significantly downregulated because of the accumulation of mis-spliced transcripts resulting from erroneous SON-mediated RNA splicing. Our data highlight SON as a master regulator governing neurodevelopment and demonstrate the importance of SON-mediated RNA splicing in human development.

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Deletions on chromosome 9q are seen in a subset of acute myeloid leukemia (AML) cases and are specifically associated with t(8;21) AML. We previously defined the commonly deleted region in del(9q) AML and characterized the genes in this interval. To determine the critical lost gene(s) that might cooperate with the AML1-ETO fusion gene produced by t(8;21), we developed a set of shRNAs directed against each gene in this region. Within this library, shRNAs to TLE1 and TLE4 were the only shRNAs capable of rescuing AML1-ETO expressing U937T-A/E cells from AML1-ETO-induced cell-cycle arrest and apoptosis. Knockdown of TLE1 or TLE4 levels increased the rate of cell division of the AML1-ETO-expressing Kasumi-1 cell line, whereas forced expression of either TLE1 or TLE4 caused apoptosis and cell death. Knockdown of Gro3, a TLE homolog in zebrafish, cooperated with AML1-ETO to cause an accumulation of noncirculating hematopoietic blast cells. IntroductionOne of the most common genetic aberrations in acute myeloid leukemia (AML) is the balanced chromosomal translocation t(8;21). This translocation, seen in 8% to 13% of de novo AML cases, 1-3 creates the RUNX1-MTG8/AML1-ETO fusion gene. AML1-ETO is insufficient for leukemogenesis as evidenced by mouse models, 4-7 the detection of fusion gene transcripts in AML patients in long-term remission, 8,9 as well as the finding of transcripts in newborns who did not develop t(8;21) AML for more than 10 years. 10 Although AML1-ETO expression promotes the maintenance of early hematopoietic precursors, 11,12 it markedly inhibits short-term expansion of primary human bone marrow cells and the proliferation of committed progenitors and CD34 ϩ cells. 13 This suggests a model in which secondary mutations are required to further transform preleukemic stem cells and allow their progeny to expand.Deletion of a portion of the long arm of chromosome 9, del(9q), is a recurring abnormality in malignant myeloid diseases reported in approximately 2% of AML cases and is nonrandomly associated with t(8;21). Approximately 36% to 50% of samples with del(9q) have t(8;21); conversely, 7% to 14% of pediatric AML samples with t(8;21) have del(9q). 1,[14][15][16] After numerical abnormalities, del(9q) is the single most common associated structural chromosomal abnormality seen with t(8;21) AML, indicating loss of function of a gene or genes on chromosome 9q may be one of the most important cooperating genes in t(8;21) AML.In a search for this cooperating gene(s), we recently narrowed the commonly deleted region (CDR) in 43 del(9q) AML samples to less than 2.4 Mb at 9q21.32-9q21.33. There are 10 known genes within, or immediately adjacent to, this region -TLE (transducin like enhancer of split)-1, FRMD3, UBQLN1, GKAP42, KIF27, HNRPK, SLC28A3, RMI1 (Q9H9A7), and NTRK2, and 3 novel or potential genes, RASEF, C9orf103 (ENSG00000148057), and C9orf64 (Q8N2B1). 17 Sequence analysis of the coding regions of these genes failed to identify clearly inactivating mutations in the remaining allele in del(9q) AML sampl...

Background: HSF1 influences chemoresistance in cancer. Results: Chemotherapy activates HSF1, leading to direct transcriptional regulation of autophagy related gene, ATG7. In vitro findings are supported by patient sample study. Conclusion: HSF1 regulates cytoprotective, heat shock-independent autophagy by directly regulating ATG7, which plays an important role in chemoresistance. Significance: Identification of novel HSF1/ATG7 axis in chemoresistance strongly supports development of robust combination therapies, targeting it in cancer.

Focal adhesion kinase (FAK) is an integrin-associated protein tyrosine kinase that is frequently overexpressed in advanced human cancers. Recent studies have demonstrated that aside from FAK’s catalytic activity in cancer cells, its cellular localization is also critical for regulating the transcription of chemokines that promote a favorable tumor microenvironment (TME) by suppressing destructive host immunity. In addition to the protumor roles of FAK in cancer cells, FAK activity within cells of the TME may also support tumor growth and metastasis through various mechanisms, including increased angiogenesis and vascular permeability and effects related to fibrosis in the stroma. Small molecule FAK inhibitors have demonstrated efficacy in alleviating tumor growth and metastasis, and some are currently in clinical development phases. However, several preclinical trials have shown increased benefits from dual therapies using FAK inhibitors in combination with other chemotherapies or with immune cell activators. This review will discuss the role of nuclear FAK as a driver for tumor cell survival as well as potential therapeutic strategies to target FAK in both tumors and the TME.

IntroductionAcute myeloid leukemia (AML) is a heterogeneous disease that is classified based on the presence of specific cytogenetic abnormalities as well as the French-American-British (FAB) classification of the leukemic cells and immunophenotype. One of the common translocations identified in leukemia is between chromosome 8q22 and chromosome 21q22 ( Figure 1a). 1 It is associated with nearly 40% of cases of FAB-M2 AML and 8% to 20% of all cases of AML depending on the genetic background and geographic location of the population. The (8;21) translocation is also observed in approximately 6% of AML M1 and, more rarely, in AML M0, M4, M5, and other myeloproliferative syndromes. 2,3 The involved genes are, on chromosome 8, MTG8 or ETO, meaning myeloid translocation gene or eight twenty-one, respectively, 4,5 and AML1 (acute myeloid leukemia factor 1) on chromosome 21. 4 The commonly used name for the t(8;21) fusion protein is AML1-MTG8 or AML1-ETO, and we refer to it as AML1-ETO in this review. AML1 was also discovered from other studies that are not related to t(8;21) and has several different names. 6 Its HUGO (Nomenclature Committee of the Human Genome Organization) name is RUNX1. In correlation, MTG8/ETO is named RUNX1T1 for RUNX1 translocation 1.The t(8;21) generates the 2 fusion genes AML1-ETO and ETO-AML1 ( Figure 1B). AML1-ETO mRNA is easily detectable using polymerase chain reaction (PCR) primers on 2 sides of the fusion point. However, ETO-AML1 mRNA was not identified using a similar approach (E. Kanbe, D.-E.Z., unpublished data, February 2003). This result indicates that the ETO-AML1 transcript is not expressed, is expressed at an extremely low level, or is highly unstable due to degradation. All of the studies on t(8;21) have therefore focused on AML1-ETO.Most of the coding region of the ETO gene is fused to the AML1 amino terminus containing the DNA-binding runt homology domain (RHD) to generate an AML1-ETO fusion protein ( Figure 1C). 4,5,7 The ETO gene has 14 exons. The original cloned AML1-ETO cDNA contained ETO exons 2 through 11; the fusion transcript produces an AML1-ETO protein of 752 amino acids ( Figure 1C). 8 The ETO portion of the full-length AML1-ETO protein contains 3 proline-serine-threonine (PST)-rich regions and 4 Nervy homology regions (NHR1-4) ( Figure 1C). 9 The PST-rich regions have multiple potential kinase phosphorylation sites (SP [Serine-Proline] and TP [Threonine-Proline]). Phosphorylation of ETO has been reported although no kinase involved in its phosphorylation has been identified. 10 NHR1, also called the TAF (TATA box binding protein associated factor) homology domain, shares a sequence similarity with TAF110 and other related TAFs. NHR2 has a hydrophobic amino acid heptad repeat, which is critical for ETO oligomerization. 11 NHR3 contains a predicted coiled-coil structure. NHR4 is a myeloid-Nervy-DEAF1 (MYND) homology domain with 2 predicted zinc finger motifs.Expression of the AML1-ETO fusion gene is under the control of the AML1 promoter. The AML1 gene has 2 promot...

In the present report, three different shapes of chitosan-capped gold nanoparticles (nanospheres, nanostars, and nanorods) were synthesized to investigate the effects of shape on cytotoxicity and cellular uptake in cancer cells. Green tea extract was utilized as a reducing agent to reduce gold salts to gold nanospheres. Gold nanostars were prepared using an as-prepared nanosphere solution as a seed solution. Gold nanorods were synthesized using a conventional method. All three types of gold nanoparticles showed their characteristic surface plasmon resonance bands upon UV-visible spectrophotometry. In high-resolution transmission electron microscopy images, lattice structures were clearly observed in all three shapes, confirming the crystalline nature of the nanoparticles. All three colloidal solutions of gold nanoparticles retained colloidal stability in various solutions. To assess cytotoxicity, the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed on four cancer cell lines. The cytotoxicity was the highest in nanorods, followed by nanostars and finally nanospheres. The cellular uptake of gold nanoparticles in human hepatocyte carcinoma cells (HepG2) was measured, and the results followed the order nanospheres > nanorods > nanostars. The outcomes of the current study may assist in the shape design of gold nanoparticles for therapeutic applications as drug delivery vehicles in the field of nanomedicine.

IntroductionThe AML1-ETO (AE) protein from a common chromosomal translocation t(8;21) contains 5 known functional domains ( Figure 1A), the Drosophila runt homology domain (RHD) from AML1 and 4 Drosophila Nervy homology regions (NHRs) from ETO. The Runt domain is responsible for binding to DNA, interacting with its heterodimerization partner core-binding factor-␤ (CBF-␤), and binding to other transcription regulators. 1,2 NHR1 shares sequence similarity with TAF110. NHR2 is critical for ETO oligomerization; NHR3 contains a predicted coiled-coil structure; NHR4 is a myeloid-Nervy-DEAF1 homology domain with zinc-chelating motifs.To understand the molecular mechanism of AE in leukemogenesis, several mouse models have been established. Studies using these models revealed that AE expression was not sufficient to induce leukemia. 3-7 However, with additional mutation(s), AE is necessary for causing acute myeloid leukemia (AML). 8,9 Recently, we identified C-terminal-truncated AE proteins (AEtr and AE9a) as potent inducers of leukemia development in mice. 10,11 Interestingly, the naturally occurring spliced isoform AE9a was detected in t(8;21) patients. 11 In this report, we investigated the importance of different known AE domains in leukemogenesis using the AE9a mouse leukemia model. Methods AnimalsThe MF-1 mice, as previously described, 10,11 were housed in a pathogenfree facility. All procedures were approved by Institutional Animal Care and Use Committee of The Scripps Research Institute. Retroviral constructionThe different ETO deletion constructs were as previously described. 12 The cDNA fragments with deletions were inserted into the MigR1-AE9a construct. MigR1-AE9aR174Q and MigR1-AEtrL148D were generated from pCDNA6-HA-AE-R174Q and pCMV5-AE-L148D, respectively. All deletion and point mutation constructs were confirmed by sequencing. Fetal liver cell isolation, retroviral infection, transplantation, and flow cytometryThese procedures were as described previously. 10,11 Mouse survival and statistic analysesThe Kaplan-Meier survival curve and statistic analyses were performed using GraphPad Prism4 software (GraphPad Software, San Diego, CA). Results and discussionTo investigate the important domains of AE in leukemogenesis, we used a series of point mutation and internal deletion mutants of C-terminal-truncated AE proteins to perform hematopoietic cell retroviral transduction and transplantation assays ( Figure 1A). The expression of these fusion proteins was confirmed by Western blotting ( Figure 1B). Based on previous reports, the L148D mutation should disrupt AE binding to DNA and CBF-␤, 13 and the R174Q mutation should prevent AE DNA binding but not significantly interfere with the interaction between AE and CBF-␤. 14 Furthermore, AE9a-delNHR1 will not interact with E proteins, 15 AE9a-delNHR2 cannot form oligomers with itself ( Figure S1, available on the Blood website; see the Supplemental Materials link at the top of the online article) or with any MTG family The online version of this article contains a d...