Extracellular Metabolic Energetics Can Promote Cancer Progression

Colon cancer progression is characterized by growth of the primary tumor in the colon followed by metastasis to distant organs. The metastatic cascade involves invasion of cells from the primary tumor into the surrounding tissue, entering into and survival of cancer cells in the circulation, arrival at the end organ and finally colonization of the end organ. The liver is the primary site of colon cancer metastatic colonization, with over 70% of colon cancer patients experiencing liver metastases. Despite current standard-of-care surgical intervention and broad spectra cytotoxic chemotherapeutics, the survival rate of patients with metastatic disease is less then 5%. A greater understanding of the biology and molecular determinants of liver colonization is therefore of great importance to the scientific and clinical community. This thesis presents unbiased approaches to identify regulators of liver metastasis in colon cancer and the elucidation of the mechanisms involved. The first part of this thesis describes the identification of two microRNAs, miR- 483-5p and miR-551a as suppressors of liver metastasis by human colon cancer cells using two parallel, complementary xenograft models of colon cancer metastasis. The first approach involved a functional library-based in vivo screen of 661 microRNAs. The second approach utilized in vivo selection of liver metastatic colon cancer cell population from poorly metastatic parental population. Functional studies revealed both microRNAs to target a common downstream effector gene, Creatine Kinase Brain (CKB). CKB was found to promote metastasis and the second part of this thesis present mechanistic studies that describe CKB-mediated modulation of intra- and extracellular energetics by colon cancer cells that contributed to colon cancer cell survival in the liver microenvironment, allowing for development of macrometastases and finally liver colonization. Further investigation identified the membrane transporter SLC6a8 as an important effector of the CKB pathway and also a promoter of colon cancer metastasis. The final part of this study reveals miR-483-5p, miR-551a, CKB and SLC6a8 to be clinically relevant across multiple patient datasets and archival patient samples. MiR-483-5p and miR-551a were found to be down-regulated in liver metastases of patients relative to primary tumors, while CKB and SLC6a8 were up-regulated. In addition, proof-of-principle therapeutic experiments involving adeno associated viral delivery of the microRNAs and small molecule inhibition of CKB and SLC6a8 demonstrated the therapeutic potential of targeting this pathway in suppressing colon cancer metastasis

Anti-tumor effect of Liqi, a traditional Chinese medicine prescription, in tumor bearing mice

<p>Abstract</p> <p>Background</p> <p><it>Liqi</it>, an herbal preparation used in traditional Chinese medicine, has been used to treat cancer in China for centuries. We investigated the anti-tumor effects of liqi and their mechanisms in mice that had been xenografted with tumors.</p> <p>Methods</p> <p>Sarcoma 180 tumor, Lewis lung carcinoma, and SGC-7901 cells were implanted in BALB/c mice, C57BL/6 mice, and BALB/c nude mice, respectively. Liqi was administered to subgroups of these mice. The tumor weight and size were measured. Cell cycle analysis and T lymphocyte subsets were determined by flow cytometry. The activity of NK cells and TNF was tested using cytotoxicity assay on YAC-1 cells and L929 cells, respectively, and the activity of IL-2 was tested with an IL-2-dependent CTLL-2 cell proliferation assay. Platelet aggregation was monitored by measuring electric impedance, and the levels of thromboxane A2 (TXA₂) and prostacyclin (PGI₂) in blood were measured by ¹²⁵I-TXB₂and ¹²⁵I-Keto-PGF_1αradioimmunoassay.</p> <p>Results</p> <p>The results showed that liqi inhibited tumor growth in tumor-implanted mice and arrested the cell proliferation in the G0/G1 phase and reduced the portion of cells in S and G2/M phase for SGC-7901 cells. Liqi increased the activity of NK cells and TNF-α, stimulated IL-2 production and activity, and regulated T lymphocyte subpopulations. Liqi inhibited the Lewis lung carcinoma metastasis by inhibiting platelet aggregation and normalizing the balance between TXA₂and PGI₂.</p> <p>Conclusion</p> <p>All these findings demonstrated that liqi has an anti-tumor effect in vivo. The mechanism may be related to immune regulation and anticoagulation effects.</p

Potential of Core-Collapse Supernova Neutrino Detection at JUNO

JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve

Detection of the Diffuse Supernova Neutrino Background with JUNO

As an underground multi-purpose neutrino detector with 20 kton liquid scintillator, Jiangmen Underground Neutrino Observatory (JUNO) is competitive with and complementary to the water-Cherenkov detectors on the search for the diffuse supernova neutrino background (DSNB). Typical supernova models predict 2-4 events per year within the optimal observation window in the JUNO detector. The dominant background is from the neutral-current (NC) interaction of atmospheric neutrinos with 12C nuclei, which surpasses the DSNB by more than one order of magnitude. We evaluated the systematic uncertainty of NC background from the spread of a variety of data-driven models and further developed a method to determine NC background within 15\% with {\it{in}} {\it{situ}} measurements after ten years of running. Besides, the NC-like backgrounds can be effectively suppressed by the intrinsic pulse-shape discrimination (PSD) capabilities of liquid scintillators. In this talk, I will present in detail the improvements on NC background uncertainty evaluation, PSD discriminator development, and finally, the potential of DSNB sensitivity in JUNO

Real-time Monitoring for the Next Core-Collapse Supernova in JUNO

Core-collapse supernova (CCSN) is one of the most energetic astrophysical events in the Universe. The early and prompt detection of neutrinos before (pre-SN) and during the SN burst is a unique opportunity to realize the multi-messenger observation of the CCSN events. In this work, we describe the monitoring concept and present the sensitivity of the system to the pre-SN and SN neutrinos at the Jiangmen Underground Neutrino Observatory (JUNO), which is a 20 kton liquid scintillator detector under construction in South China. The real-time monitoring system is designed with both the prompt monitors on the electronic board and online monitors at the data acquisition stage, in order to ensure both the alert speed and alert coverage of progenitor stars. By assuming a false alert rate of 1 per year, this monitoring system can be sensitive to the pre-SN neutrinos up to the distance of about 1.6 (0.9) kpc and SN neutrinos up to about 370 (360) kpc for a progenitor mass of 30$M_{\odot}$ for the case of normal (inverted) mass ordering. The pointing ability of the CCSN is evaluated by using the accumulated event anisotropy of the inverse beta decay interactions from pre-SN or SN neutrinos, which, along with the early alert, can play important roles for the followup multi-messenger observations of the next Galactic or nearby extragalactic CCSN.Comment: 24 pages, 9 figure

The Transcriptional Activator Krüppel-like Factor-6 Is Required for CNS Myelination

Growth factors of the gp130 family promote oligodendrocyte differentiation, and viability, and myelination, but their mechanisms of action are incompletely understood. Here, we show that these effects are coordinated, in part, by the transcriptional activator Krüppel-like factor-6 (Klf6). Klf6 is rapidly induced in oligodendrocyte progenitors (OLP) by gp130 factors, and promotes differentiation. Conversely, in mice with lineage-selective Klf6 inactivation, OLP undergo maturation arrest followed by apoptosis, and CNS myelination fails. Overlapping transcriptional and chromatin occupancy analyses place Klf6 at the nexus of a novel gp130-Klf-importin axis, which promotes differentiation and viability in part via control of nuclear trafficking. Klf6 acts as a gp130-sensitive transactivator of the nuclear import factor importin-α5 (Impα5), and interfering with this mechanism interrupts step-wise differentiation. Underscoring the significance of this axis in vivo, mice with conditional inactivation of gp130 signaling display defective Klf6 and Impα5 expression, OLP maturation arrest and apoptosis, and failure of CNS myelination

Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples

Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts

Effects of gender roles and apprehension on SMS usage in Singapore.

An exploratory and descriptive study on the role of gender in Short Messaging Service (SMS) usage and how an individual's level of anxiety affects whether SMS is used in apprehensive situations, in the context of Singapore

Depression anxiety stress scales (DASS-21): Psychometric analysis among Malaysian university student during covid-19 pandemic

The aim of this study is to test the psychometric properties of the 21-item Depression Anxiety Stress Scale (DASS-21). The DASS-21 is a set of three self-report scales consisting of 21 items to measure the emotional states of depression, anxiety, and stress. A sample of 380 (256 female, 124 male) university students in Malaysia were randomly selected to participate in this study. The reliability of the DASS-21 was evaluated by measuring the internal consistency (Cronbach’s alpha) reliability. The convergent, concurrent, and discriminant properties were examined to evaluate the validity of the scale. Item analysis was also performed through the item-total correlation approach. The reliability of the DASS-21 showed excellent Cronbach’s alpha values of .916 and .891 for the subscales of depression and anxiety respectively, while the stress subscale showed low reliability with Cronbach’s alpha value of .472. The convergent validity of the DASS-21 was tested by examining the relationship between the dimensions of the scale which have moderate to strong and positive correlations ranging from r = .561 to .777. The concurrent validity was assessed by examining the relationship between the three subscales of DASS-21 and the score of the Warwick- Edinburgh Mental Well-Being Scale (WEMWBS) which showed negative and significant correlations ranging from r = -.377 to -.615. The discriminant validity was evaluated by factor analyzing items of DASS-21 and items of World Health Organization Quality of Life, WHOQOLBref (Field Trial Version). All items of DASS-21 were loaded in one component while the items of WHOQOL-Bref (Field Trial Version) were loaded in another component, except for 3 items. The item analysis showed that the item-total correlation coefficient for three subscales of DASS-21 exceeded the recommended value of .30, except for item 14. From this study, the DASS-21 showed a high reliability and validity score and can be used to assess and measure mental health states among university students in Malaysia during the COVID-19 pandemic. However, further studies are required to enhance the evidence of reliability and validity for the DASS-21 instrument

Functional genetic screen identifies ITPR3/calcium/RELB axis as a driver of colorectal cancer metastatic liver colonization

Metastatic colonization is the primary cause of death from colorectal cancer (CRC). We employed genome-scale in&nbsp;vivo short hairpin RNA (shRNA) screening and validation to identify 26 promoters of CRC liver colonization. Among these genes, we identified a cluster that contains multiple targetable genes, including ITPR3, which promoted liver-metastatic colonization and elicited similar downstream gene expression programs. ITPR3 is a caffeine-sensitive inositol 1,4,5-triphosphate (IP3) receptor that releases calcium from the endoplasmic reticulum and enhanced metastatic colonization by inducing expression of RELB, a transcription factor that is associated with non-canonical NF-κB signaling. Genetic, cell biological, pharmacologic, and clinical association studies revealed that ITPR3 and RELB drive CRC colony formation by promoting cell survival upon substratum detachment or hypoxic exposure. RELB was sufficient to drive colonization downstream of ITPR3. Our findings implicate the ITPR3/calcium/RELB axis in CRC metastatic colony formation and uncover multiple clinico-pathologically associated targetable proteins as drivers of CRC metastatic colonization