Somatic A-to-I RNA-edited RHOA isoform 2 specific-R176G mutation promotes tumor progression in lung adenocarcinoma.

Adenosine-to-inosine (A-to-I) RNA editing is the most common posttranscriptional editing to create somatic mutations and increase proteomic diversity. However, the functions of the edited mutations are largely underexplored. To identify novel targets in lung adenocarcinoma (LUAD), we conducted a genome-wide somatic A-to-I RNA editing analysis of 23 paired adjacent normal and LUAD transcriptomes and identified 26,280 events, including known nonsynonymous AZIN1-S367G and novel RHOAiso2 (RHOA isoform 2)-R176G, tubulin gamma complex associated protein 2 (TUBGCP2)-N211S, and RBMXL1-I40 M mutations. We validated the edited mutations in silico in multiple databases and in newly collected LUAD tissue pairs with the SEQUENOM MassARRAY® and TaqMan PCR Systems. We selected RHOAiso2-R176G due to its significant level, isoform-specificity, and being the most common somatic edited nonsynonymous mutation of RHOAiso2 to investigate its roles in LUAD tumorigenesis. RHOAiso2 is a ubiquitous but low-expression alternative spliced isoform received a unique Alu-rich exon at the 3' RHOA mRNA to become an editing RNA target, leading to somatic hypermutation and protein diversity. Interestingly, LUAD patients harboring the RHOAiso2-R176G mutation were associated with aberrant RHOA functions, cancer cell proliferation and migration, and poor clinical outcomes in transcriptome analysis. Mechanistically, RHOAiso2-R176G mutation-expressing LUAD cells potentiate RHOA-guanosine triphosphate (GTP) activity to phosphorylate ROCK1/2 effectors and enhance cell proliferation and migration in vitro and increase tumor growth in xenograft and systemic metastasis models in vivo. Taken together, the RHOAiso2-R176G mutation is a common somatic A-to-I edited mutation of the hypermutated RHOA isoform 2. It is an oncogenic and isoform-specific theranostic target that activates RHOA-GTP/p-ROCK1/2 signaling to promote tumor progression.

Long noncoding RNA Smyca coactivates TGF-ß/Smad and Myc pathways to drive tumor progression.

BACKGROUND: Metastasis and chemoresistance are major culprits of cancer mortality, but factors contributing to these processes are incompletely understood. METHODS: Bioinformatics methods were used to identify the relations of Smyca expression to clinicopathological features of human cancers. RNA-sequencing analysis was used to reveal Smyca-regulated transcriptome. RNA pull-down and RNA immunoprecipitation were used to examine the binding of Smyca to Smad3/4 and c-Myc/Max. Chromatin immunoprecipitation and chromatin isolation by RNA purification were used to determine the binding of transcription factors and Smyca to various gene loci, respectively. Real-time RT-PCR and luciferase assay were used to examine gene expression levels and promoter activities, respectively. Xenograft mouse models were performed to evaluate the effects of Smyca on metastasis and chemoresistance. Nanoparticle-assisted gapmer antisense oligonucleotides delivery was used to target Smyca in vivo. RESULTS: We identify lncRNA Smyca for its association with poor prognosis of many cancer types. Smyca potentiates metabolic reprogramming, migration, invasion, cancer stemness, metastasis and chemoresistance. Mechanistically, Smyca enhances TGF-ß/Smad signaling by acting as a scaffold for promoting Smad3/Smad4 association and further serves as a Smad target to amplify/prolong TGF-ß signaling. Additionally, Smyca potentiates c-Myc-mediated transcription by enhancing the recruitment of c-Myc/Max complex to a set of target promoters and c-Myc binding to TRRAP. Through potentiating TGF-ß and c-Myc pathways, Smyca synergizes the Warburg effect elicited by both pathways but evades the anti-proliferative effect of TGF-ß. Targeting Smyca prevents metastasis and overcomes chemoresistance. CONCLUSIONS: This study uncovers a lncRNA that coordinates tumor-relevant pathways to orchestra a pro-tumor program and establishes the clinical values of Smyca in cancer prognosis and therapy.

Prognostic comparative genes predict targets for sorafenib combination therapies in hepatocellular carcinoma.

With the increasing incidence and mortality of human hepatocellular carcinoma (HCC) worldwide, revealing innovative targets to improve therapeutic strategies is crucial for prolonging the lives of patients. To identify innovative targets, we conducted a comprehensive comparative transcriptome analysis of 5,410 human HCCs and 974 mouse liver cancers to identify concordantly expressed genes associated with patient survival. Among the 664 identified prognostic comparative HCC (pcHCC) genes, upregulated pcHCC genes were associated with prognostic clinical features, including large tumor size, vascular invasion and late HCC stages. Interestingly, after validating HCC patient prognoses in multiple independent datasets, we matched the 664 aberrant pcHCC genes with the sorafenib-altered genes in TCGA_LIHC patients and found these 664 pcHCC genes were enriched in sorafenib-related functions, such as downregulated xenobiotic and lipid metabolism and upregulated cell proliferation. Therapeutic agents targeting aberrant pcHCC genes presented divergent molecular mechanisms, including suppression of sorafenib-unrelated oncogenic pathways, induction of sorafenib-unrelated ferroptosis, and modulation of sorafenib transportation and metabolism, to potentiate sorafenib therapeutic effects in HCC combination therapy. Moreover, the pcHCC genes NCAPG and CENPW, which have not been targeted in combination with sorafenib treatment, were knocked down and combined with sorafenib treatment, which reduced HCC cell viability based on disruption to the p38/STAT3 axis, thereby hypersensitizing HCC cells. Together, our results provide important resources and reveal that 664 pcHCC genes represent innovative targets suitable for developing therapeutic strategies in combination with sorafenib based on the divergent synergistic mechanisms for HCC tumor suppression.

A novel HIF1α-STIL-FOXM1 axis regulates tumor metastasis.

BACKGROUND: Metastasis is the major cause of morbidity and mortality in cancer that involves in multiple steps including epithelial-mesenchymal transition (EMT) process. Centrosome is an organelle that functions as the major microtubule organizing center (MTOC), and centrosome abnormalities are commonly correlated with tumor aggressiveness. However, the conclusive mechanisms indicating specific centrosomal proteins participated in tumor progression and metastasis remain largely unknown. METHODS: The expression levels of centriolar/centrosomal genes in various types of cancers were first examined by in silico analysis of the data derived from The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), and European Bioinformatics Institute (EBI) datasets. The expression of STIL (SCL/TAL1-interrupting locus) protein in clinical specimens was further assessed by Immunohistochemistry (IHC) analysis and the oncogenic roles of STIL in tumorigenesis were analyzed using in vitro and in vivo assays, including cell migration, invasion, xenograft tumor formation, and metastasis assays. The transcriptome differences between low- and high-STIL expression cells were analyzed by RNA-seq to uncover candidate genes involved in oncogenic pathways. The quantitative polymerase chain reaction (qPCR) and reporter assays were performed to confirm the results. The chromatin immunoprecipitation (ChIP)-qPCR assay was applied to demonstrate the binding of transcriptional factors to the promoter. RESULTS: The expression of STIL shows the most significant increase in lung and various other types of cancers, and is highly associated with patients' survival rate. Depletion of STIL inhibits tumor growth and metastasis. Interestingly, excess STIL activates the EMT pathway, and subsequently enhances cancer cell migration and invasion. Importantly, we reveal an unexpected role of STIL in tumor metastasis. A subset of STIL translocate into nucleus and associate with FOXM1 (Forkhead box protein M1) to promote tumor metastasis and stemness via FOXM1-mediated downstream target genes. Furthermore, we demonstrate that hypoxia-inducible factor 1α (HIF1α) directly binds to the STIL promoter and upregulates STIL expression under hypoxic condition. CONCLUSIONS: Our findings indicate that STIL promotes tumor metastasis through the HIF1α-STIL-FOXM1 axis, and highlight the importance of STIL as a promising therapeutic target for lung cancer treatment.

PSPC1 is a new contextual determinant of aberrant subcellular translocation of oncogenes in tumor progression.

Dysregulation of nucleocytoplasmic shuttling is commonly observed in cancers and emerging as a cancer hallmark for the development of anticancer therapeutic strategies. Despite its severe adverse effects, selinexor, a selective first-in-class inhibitor of the common nuclear export receptor XPO1, was developed to target nucleocytoplasmic protein shuttling and received accelerated FDA approval in 2019 in combination with dexamethasone as a fifth-line therapeutic option for adults with relapsed refractory multiple myeloma (RRMM). To explore innovative targets in nucleocytoplasmic shuttling, we propose that the aberrant contextual determinants of nucleocytoplasmic shuttling, such as PSPC1 (Paraspeckle component 1), TGIF1 (TGF-ß Induced Factor Homeobox 1), NPM1 (Nucleophosmin), Mortalin and EBP50, that modulate shuttling (or cargo) proteins with opposite tumorigenic functions in different subcellular locations could be theranostic targets for developing anticancer strategies. For instance, PSPC1 was recently shown to be the contextual determinant of the TGF-ß prometastatic switch and PTK6/ß-catenin reciprocal oncogenic nucleocytoplasmic shuttling during hepatocellular carcinoma (HCC) progression. The innovative nucleocytoplasmic shuttling inhibitor PSPC1 C-terminal 131 polypeptide (PSPC1-CT131), which was developed to target both the shuttling determinant PSPC1 and the shuttling protein PTK6, maintained their tumor-suppressive characteristics and exhibited synergistic effects on tumor suppression in HCC cells and mouse models. In summary, targeting the contextual determinants of nucleocytoplasmic shuttling with cargo proteins having opposite tumorigenic functions in different subcellular locations could be an innovative strategy for developing new therapeutic biomarkers and agents to improve cancer therapy.

PSPC1 Potentiates IGF1R Expression to Augment Cell Adhesion and Motility.

Paraspeckle protein 1 (PSPC1) overexpression in cancers is known to be the pro-metastatic switch of tumor progression associated with poor prognosis of cancer patients. However, the detail molecular mechanisms to facilitate cancer cell migration remain elusive. Here, we conducted integrated analysis of human phospho-kinase antibody array, transcriptome analysis with RNA-seq, and proteomic analysis of protein pulldown to study the molecular detail of PSPC1-potentiated phenotypical transformation, adhesion, and motility in human hepatocellular carcinoma (HCC) cells. We found that PSPC1 overexpression re-assembles and augments stress fiber formations to promote recruitment of focal adhesion contacts at the protruding edge to facilitate cell migration. PSPC1 activated focal adhesion-associated kinases especially FAK/Src signaling to enhance cell adhesion and motility toward extracellular matrix (ECM). Integrated transcriptome and gene set enrichment analysis indicated that PSPC1 modulated receptor tyrosine kinase IGF1R involved in the focal adhesion pathway and induction of diverse integrins expression. Knockdown IGF1R expression and treatment of IGF1R inhibitor suppressed PSPC1-induced cell motility. Interestingly, knockdown PSPC1-interacted paraspeckle components including NONO, FUS, and the lncRNA Neat1 abolished PSPC1-activated IGF1R expression. Together, PSPC1 overexpression induced focal adhesion formation and facilitated cell motility via activation of IGF1R signaling. PSPC1 overexpression in tumors could be a potential biomarker of target therapy with IGF1R inhibitor for improvement of HCC therapy.

PSPC1: a contextual determinant of tumor progression.

Protein-tyrosine kinase 6 (PTK6) sequestrated by its substrate paraspeckle component 1 (PSPC1) in nucleus is a tumor suppressor. PSPC1 functions as a contextual determinant of oncogenic subcellular translocations to synergize PSPC1/ß-catenin and PTK6 tumorigenesis. Besides, PSPC1 C-terminal interacting domain (PSPC1-CT131), a dual inhibitor of PSPC1 and PTK6, suppresses cancer progression.

Targeting protein tyrosine phosphatase PTP-PEST (PTPN12) for therapeutic intervention in acute myocardial infarction.

AIMS: The myocardial ischaemia/reperfusion (I/R) injury is almost inevitable since reperfusion is the only established treatment for acute myocardial infarction (AMI). To date there is no effective strategy available for reducing the I/R injury. Our aim was to elucidate the mechanisms underlying myocardial I/R injury and to develop a new strategy for attenuating the damage it causes. METHODS AND RESULTS: Using a mouse model established by ligation of left anterior descending artery, we found an increase in activity of protein tyrosine phosphatases (PTPs) in myocardium during I/R. Treating the I/R-mice with a pan-PTP inhibitor phenyl vinyl sulfone attenuated I/R damage, suggesting PTP activation to be harmful in I/R. Through analysing RNAseq data, we showed PTPs being abundantly expressed in mouse myocardium. By exposing primary cardiomyocytes ablated with specific endogenous PTPs by RNAi to hypoxia/reoxygenation (H/R), we found a role that PTP-PEST (PTPN12) plays to promote cell death under H/R stress. Auranofin, a drug being used in clinical practice for treating rheumatoid arthritis, may target PTP-PEST thus suppressing its activity. We elucidated the molecular basis for Auranofin-induced inactivation of PTP-PEST by structural studies, and then examined its effect on myocardial I/R injury. In the mice receiving Auranofin before reperfusion, myocardial PTP activity was suppressed, leading to restored phosphorylation of PTP-PEST substrates, including ErbB-2 that maintains the survival signalling of the heart. In line with the inhibition of PTP-PEST activity, the Auranofin-treated I/R-mice had smaller infarct size and better cardiac function. CONCLUSIONS: PTP-PEST contributes to part of the damages resulting from myocardial I/R. The drug Auranofin, potentially acting through the PTP-PEST-ErbB-2 signalling axis, reduces myocardial I/R injury. Based on this finding, Auranofin could be used in the development of new treatments that manage I/R injury in patients with AMI.

Integrative analyses of noncoding RNAs reveal the potential mechanisms augmenting tumor malignancy in lung adenocarcinoma.

Precise noncoding RNA (ncRNA)-based network prediction is necessary to reveal ncRNA functions and pathological mechanisms. Here, we established a systemic pipeline to identify prognostic ncRNAs, predict their functions and explore their pathological mechanisms in lung adenocarcinoma (LUAD). After in silico and experimental validation based on evaluations of prognostic value in multiple LUAD cohorts, we selected the PTTG3P pseudogene from among other prognostic ncRNAs (MIR497HG, HSP078, TBX5-AS1, LOC100506990 and C14orf64) for mechanistic studies. PTTG3P upregulation in LUAD cells shortens the metaphase to anaphase transition in mitosis, increases cell viability after cisplatin or paclitaxel treatment, facilitates tumor growth that leads to poor survival in orthotopic lung models, and is associated with a poor survival rate in LUAD patients in the TCGA cohort who received chemotherapy. Mechanistically, PTTG3P acts as an ncRNA that interacts with the transcription factor FOXM1 to regulate the transcriptional activation of the mitotic checkpoint kinase BUB1B, which augments tumor growth and chemoresistance and leads to poor outcomes for LUAD patients. Overall, we established a systematic strategy to uncover prognostic ncRNAs with functional prediction methods suitable for pan-cancer studies. Moreover, we revealed that PTTG3P, due to its upregulation of the PTTG3P/FOXM1/BUB1B axis, could be a therapeutic target for LUAD patients.

PSPC1-interchanged interactions with PTK6 and ß-catenin synergize oncogenic subcellular translocations and tumor progression.

Hepatocellular carcinoma (HCC) is one of the most lethal cancers worldwide due to metastasis. Paraspeckle component 1 (PSPC1) upregulation has been identified as an HCC pro-metastatic activator associated with poor patient prognosis, but with a lack of targeting strategy. Here, we report that PSPC1, a nuclear substrate of PTK6, sequesters PTK6 in the nucleus and loses its metastasis driving capability. Conversely, PSPC1 upregulation or PSPC1-Y523F mutation promotes epithelial-mesenchymal transition, stemness, and metastasis via cytoplasmic translocation of active PTK6 and nuclear translocation of ß-catenin, which interacts with PSPC1 to augment Wnt3a autocrine signaling. The aberrant nucleocytoplasmic shuttling of active PTK6/ß-catenin is reversed by expressing the PSPC1 C-terminal interacting domain (PSPC1-CT131), thereby suppressing PSPC1/PTK6/ß-catenin-activated metastasis to prolong the survival of HCC orthotopic mice. Thus, PSPC1 is the contextual determinant of the oncogenic switch of PTK6/ß-catenin subcellular localizations, and PSPC1-CT131 functions as a dual inhibitor of PSPC1 and PTK6 with potential for improving cancer therapy.

A New Switch for TGFß in Cancer.

The TGFß cytokine plays dichotomous roles during tumor progression. In normal and premalignant cancer cells, the TGFß signaling pathway inhibits proliferation and promotes cell-cycle arrest and apoptosis. However, the activation of this pathway in late-stage cancer cells could facilitate the epithelial-to-mesenchymal transition, stemness, and mobile features to enhance tumorigenesis and metastasis. The opposite functions of TGFß signaling during tumor progression make it a challenging target to develop anticancer interventions. Nevertheless, the recent discovery of cellular contextual determinants, especially the binding partners of the transcription modulators Smads, is critical to switch TGFß responses from proapoptosis to prometastasis. In this review, we summarize the recently identified contextual determinants (such as PSPC1, KLF5, 14-3-3ζ, C/EBPß, and others) and the mechanisms of how tumor cells manage the context-dependent autonomous TGFß responses to potentiate tumor progression. With the altered expression of some contextual determinants and their effectors during tumor progression, the aberrant molecular prometastatic switch might serve as a new class of theranostic targets for developing anticancer strategies.

PSPC1 potentiates TGF-ß-dependent metastatic dissemination.

Metastatic reprogramming toward malignant tumor progression relies on the activation of oncogenic regulators, yet the cellular determinants remain elucidated. Through identification of aberrant prognostic cancer genes, we identified paraspeckle component 1 (PSPC1) functions as a master activator of metastatic reprogramming by activating epithelial-to-mesenchymal transition (EMT), stemness and TGF-ß1 pro-metastatic switch.

Mutations in NOTCH1 and nucleotide excision repair genes are correlated with prognosis of hepatitis B virus-associated hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is the fifth most common cancer and the second leading cause of cancer-related mortality because of its poor prognosis. Therefore, identifying targetable genetic mutations and mutational signatures associated with prognosis and treatment strategies are needed. Ultra-deep sequencing of 409 cancer genes using formalin-fixed paraffin-embedded tissue from 33 male patients with hepatitis B virus-associated HCC was performed to identify mutational signatures associated with the prognosis of HCC. A total of 47 genes were found to be mutated in more than 10% of patients. Chromatin remodeling genes were overrepresented in the mutation profile. We found patient survival was associated with mutations in NOTCH1 and the nucleotide excision repair genes which have not been described previously in HCC. From the mutation profile, six patients were eligible for Sorafenib treatment. Among the remaining patients, 7 patients had mutations in genes that are targets for other cancer drugs and 16 patients had mutations in potentially targetable genes. Only one patient carried no potential drug target. We identified mutational signatures associated with the patient survival of HCC. The findings may facilitate identifying subgroups of patients with a poor prognosis as well as potential drug targets for use in personalized strategies for HCC treatment.

EIF3C-enhanced exosome secretion promotes angiogenesis and tumorigenesis of human hepatocellular carcinoma.

Targeting tumor angiogenesis is a common strategy against human hepatocellular carcinoma (HCC). However, identification of molecular targets as biomarker for elevating therapeutic efficacy is critical to prolong HCC patient survival. Here, we showed that EIF3C (eukaryotic translation initiation factor 3 subunit C) is upregulated during HCC tumor progression and associated with poor patient survival. Expression of EIF3C did not alter proliferation and expression of other tumor progressive genes such as HIF1A, TGFß1 and VEGF, but reduced cell migration in HCC cells. Nevertheless, expression of EIF3C in HCC cells significantly increase secretion of extracellular exosomes confirmed by increased exosomes labelling by PKH26 fluorescent dye, vesicles in exosome size detected by electronic microscopy and nanoparticle tracking analysis, and expression of divergent exosome markers. The EIF3C-increased exosomes were oncogenic to potentiate tumor angiogenesis via tube formation of HUVEC cells and growth of vessels by plugs assays on nude mice. Subcutaneous inoculation of EIF3C-exosomes mixed with Huh7 HCC cells not only promoted growth of vessels but also increased expression of EIF3C in tumors. Conversely, treatment of exosome inhibitor GW4869 reversed aforementioned oncogenic assays. We identified EIF3C activated expression of S100A11 involved in EIF3C-exosome increased tube formation in angiogenesis. Simultaneous high expression of EIF3C and S100A11 in human HCC tumors for RNA level in TCGA and protein level by IHC are associated with poor survival of HCC patients. Collectively, our results demonstrated that EIF3C overexpression is a potential target of angiogenesis for treatment with exosome inhibitor or S100A11 reduction to suppress HCC angiogenesis and tumorigenesis.

PSPC1 mediates TGF-ß1 autocrine signalling and Smad2/3 target switching to promote EMT, stemness and metastasis.

Activation of metastatic reprogramming is critical for tumour metastasis. However, more detailed knowledge of the underlying mechanism is needed to enable targeted intervention. Here, we show that paraspeckle component 1 (PSPC1), identified in an aberrant 13q12.11 locus, is upregulated and associated with poor survival in patients with cancer. PSPC1 promotes tumorigenesis, epithelial-to-mesenchymal transition (EMT), stemness and metastasis in multiple cell types and in spontaneous mouse cancer models. PSPC1 is the master activator for transcription factors of EMT and stemness and accompanies c-Myc activation to facilitate tumour growth. PSPC1 increases transforming growth factor-ß1 (TGF-ß1) secretion through an interaction with phosphorylated and nuclear Smad2/3 to potentiate TGF-ß1 autocrine signalling. Moreover, PSPC1 acts as a contextual determinant of the TGF-ß1 pro-metastatic switch to alter Smad2/3 binding preference from tumour-suppressor to pro-metastatic genes. Having validated the PSPC1-Smads-TGF-ß1 axis in various cancers, we conclude that PSPC1 is a master activator of pro-metastatic switches and a potential target for anti-metastasis drugs.

CISD2 Haploinsufficiency Disrupts Calcium Homeostasis, Causes Nonalcoholic Fatty Liver Disease, and Promotes Hepatocellular Carcinoma.

CISD2 is located within the chromosome 4q region frequently deleted in hepatocellular carcinoma (HCC). Mice with Cisd2 heterozygous deficiency develop a phenotype similar to the clinical manifestation of nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). Cisd2 haploinsufficiency causes a low incidence (20%) of spontaneous HCC and promotes HBV-associated and DEN-induced HCC; conversely, 2-fold overexpression of Cisd2 suppresses HCC in these models. Mechanistically, Cisd2 interacts with Serca2b and mediates its Ca2+ pump activity via modulation of Serca2b oxidative modification, which regulates ER Ca2+ uptake and maintains intracellular Ca2+ homeostasis in the hepatocyte. CISD2 haploinsufficiency disrupts calcium homeostasis, causing ER stress and subsequent NAFLD and NASH. Hemizygous deletion and decreased expression of CISD2 are detectable in a substantial fraction of human HCC specimens. These findings substantiate CISD2 as a haploinsufficient tumor suppressor and highlights Cisd2 as a drug target when developing therapies to treat NAFLD/NASH and prevent HCC.

Pyrimidine metabolic rate limiting enzymes in poorly-differentiated hepatocellular carcinoma are signature genes of cancer stemness and associated with poor prognosis.

Cellular metabolism of cancer cell is generally recognized to provide energy for facilitating tumor growth, but little is known about the aberrant metabolism in tumor progression and its prognostic value. Here, we applied integrated genomic approach to uncover the aberrant expression of metabolic enzymes in poorly-differentiated human hepatocellular carcinoma (HCC) for revealing targets against HCC malignancy. A total of 135 upregulated (22 are rate-limiting enzymes (RLEs)) and 362 down-regulated (77 are RLEs) metabolic genes were identified and associated with poor patient survival in large-cohorts of HCC patients in TCGA-LIHC and two other independent transcriptomic studies. Ten out of 22 upregulated RLEs in poorly-differentiated HCC are critical enzymes in pyrimidine metabolism pathways in association with stemness features by gene enrichment analysis and upregulated in ALDH1+ stem-like HCC subpopulations. By focusing on three RLEs including TK1, TYMS and DTYMK of dTTP biosynthesis pathway, expression of 3 RLEs in well-differentiated HCC cells increased ALDH1+ and spheroid stemness population but reversed by knockdown in poorly-differentiated HCC cells. Up-regulated 3 RLEs in HCC were associated with poor patient survival in multiple cohorts. Together, we identified aberrant pyrimidine pathway in poorly-differentiated HCC promotes cancer stemness served as potential theranostic target for battling HCC tumor progression.

Identification of novel cancer fusion genes using chromosome breakpoint screening.

Gene fusion due to rearrangement or translocation of chromosomes is a powerful mutational mechanism during tumorigenesis. Several new high-resolution technologies have recently been developed to evaluate large numbers of small aberrations as candidate loci for fusion gene screening. In our previous whole-genome screening study using 500K SNP arrays, we identified more than 700 homozygous deletions (HDs) and amplicons in 23 cancer cell lines. To explore novel fusion genes in cancer, we established stringent criteria for defining HD and amplicon breakpoints. Then genomic PCR and sequencing analyses identified a fusion gene, FNDC3B-PRKCI, that resulted from chromosome intra-rearrangement. Western blotting and 3'-RACE analyses revealed that the chimeric transcript was an in-frame fusion between FNDC3B and PRKCI. Finally, cell migration and colony formation assays suggested that FNDC3B-PRKCI is a potential oncogene.

Genome-wide linkage analysis and regional fine mapping identified variants in the RYR3 gene as a novel quantitative trait locus for circulating adiponectin in Chinese population.

Adiponectin is adipocyte-secreted cytokine with potent insulin-sensitizing action in peripheral tissues. The heritability of plasma adiponectin is high in Han Chinese population.To identify genetic loci influencing plasma adiponectin levels in Chinese population, we performed a genome-wide linkage scan in 1949 Chinese participants of the Stanford Asia-Pacific Program for Hypertension and Insulin Resistance family study and mapped a quantitative trail locus located on chromosome 15 at 31 cM (logarithm of odds = 3.04) with 1-logarithm of odds support interval at 24 to 34 cM. Within this mapped region, we further genotyped a total of 68 single-nucleotide polymorphisms in 12 genes. Association analysis revealed that haplotypes composed of single-nucleotide polymorphisms in the ryanodine receptor 3 (RYR3) gene had strongest association with plasma adiponectin. RYR3 haplotypes were also associated with systolic (P = 0.001) and diastolic (P = 7.1 × 10) blood pressure and high-density lipoprotein cholesterol (P = 1.4 × 10). Furthermore, an inverse relationship between expression of RYR3 and adiponectin was observed in human abdominal adipose tissue. In conclusion, a genome-wide linkage scan and regional association fine-mapping identified variants in the RYR3 gene as a quantitative trail locus for plasma adiponectin levels in Chinese population.