In Vivo Genome-Wide CRISPR Activation Screening Identifies Functionally Important Long Noncoding RNAs in Hepatocellular Carcinoma.

BACKGROUND & AIMS: Long noncoding RNAs (lncRNAs) are found to have profound impacts on diverse cellular processes. Although high-throughput sequencing studies have shown the differential lncRNA expression profiles between hepatocellular carcinoma (HCC) and nontumor livers, the functional impacts of lncRNAs on HCC development await further investigation. Herein, we sought to address the functional roles of lncRNAs in HCC pathogenesis by in vivo functional screening. METHODS: We performed genome-wide clustered regularly interspaced short palindromic repeats (CRISPR)/dead CRISPR-associated protein 9 (dCas9) lncRNA activation screening in HCC xenografts. We characterized the clinical relevance of positively selected lncRNAs using transcriptomic data sets. We used CRISPR-based gene activation and knockdown approaches to show the functional roles of positively selected lncRNAs including Cancer Susceptibility 11 (CASC11) in HCC. RNA sequencing and chromatin isolation by RNA purification sequencing were used to investigate the molecular mechanisms of CASC11 in HCC progression. RESULTS: The in vivo functional screening identified 1603 positively selected lncRNAs, 538 of which were overexpressed in HCC patients. Systematic transcriptomic data analysis and clinical investigation showed that patients with high expression of these lncRNA candidates correlated with aggressive tumor behaviors. Overexpression of these lncRNAs aggravated HCC cell growth. Detailed characterization of a lncRNA candidate, CASC11, showed its pivotal role in cell proliferation and tumor growth. Mechanistically, chromatin isolation by RNA purification sequencing showed that CASC11 was bound to the CASC11/MYC proto-oncogene shared promoter region on chromosome 8q24. CASC11 modulated the transcriptional activity of MYC in a cis-regulatory manner, which affected the expression of MYC downstream target genes, consequently promoting G1/S progression. CONCLUSIONS: Our study showed the power of in vivo CRISPR screening, which comprehensively investigated the functionality of lncRNAs in HCC progression, providing a rationale for targeting these lncRNAs clinically.

Genome-wide CRISPR-Cas9 knockout library screening identified PTPMT1 in cardiolipin synthesis is crucial to survival in hypoxia in liver cancer.

Hypoxia, low oxygen (O2), is a key feature of all solid cancers, including hepatocellular carcinoma (HCC). Genome-wide CRISPR-Cas9 knockout library screening is used to identify reliable therapeutic targets responsible for hypoxic survival in HCC. We find that protein-tyrosine phosphatase mitochondrial 1 (PTPMT1), an important enzyme for cardiolipin (CL) synthesis, is the most significant gene and ranks just after hypoxia-inducible factor (HIF)-1α and HIF-1ß as crucial to hypoxic survival. CL constitutes the mitochondrial membrane and ensures the proper assembly of electron transport chain (ETC) complexes for efficient electron transfer in respiration. ETC becomes highly unstable during hypoxia. Knockout of PTPMT1 stops the maturation of CL and impairs the assembly of ETC complexes, leading to further electron leakage and ROS accumulation at ETC in hypoxia. Excitingly, HCC cells, especially under hypoxic conditions, show great sensitivity toward PTPMT1 inhibitor alexidine dihydrochloride (AD). This study unravels the protective roles of PTPMT1 in hypoxic survival and cancer development.

Neuroprotective effect of Da Chuanxiong Formula against cognitive and motor deficits in a rat controlled cortical impact model of traumatic brain injury.

ETHNOPHARMACOLOGICAL RELEVANCE: Da Chuanxiong Formula (DCXF) is one of the famous herb pairs that contains dried rhizomes of Ligusticum chuanxiong Hort. and Gastrodia elata Bl. in the mass ratio of 4:1. This classic representative traditional Chinese medicine has been widely used to treat brain diseases like headache and migraine caused by blood stasis and wind pathogen. However, the therapeutic effect of DCXF on traumatic brain injury (TBI) has not been reported yet. AIM OF STUDY: The present study was performed to investigate the neuroprotective effects of DCXF and its underlying mechanisms in the controlled cortical impact (CCI)-induced TBI rat model. MATERIALS AND METHODS: Male Sprague-Dawley rats were divided into four groups: Sham, TBI control, 1X DCXF (520.6 mg/kg) and 5X DCXF (2603.0 mg/kg). Two treatment groups (1X and 5X DCXF) were intragastrically administered daily for 7 days before CCI-induced TBI and then DCXF treatments were continued post-TBI until the animal behavioral tests, including Morris water maze test, acceleration rotarod motor test and CatWalk quantitative gait analysis test, were done. The brain water content and blood brain barrier (BBB) integrity were measured by wet-dry weight method and Evans blue method, respectively. The number of neuron cells, neural stem cells (NSCs), GFAP positive cells (astrocyte) as well as Iba-1 positive cells (microglia) were determined by histology and immunohistochemistry. RESULTS: Treatment with DCXF significantly improved the learning ability and memory retention in Morris water maze test, and remarkably enhanced motor performances in acceleration rotarod motor test and catwalk quantitative gait analysis test after TBI. Moreover, DCXF treatment was able to reduce BBB permeability, brain edema, microglia and astrocyte activation, improve the proliferation of NSCs and decrease neurons loss in the brain with TBI. CONCLUSIONS: The present study demonstrated that DCXF treatment could decrease BBB leakage and brain edema, reduce neuron loss, microglia and astrocyte activation, and increase NSCs proliferation, which may contribute to the cognitive and motor protection of DCXF in the TBI rats. It is the first time to provide potentially underlying mechanisms of the neuroprotective effect of DCXF on TBI-induced brain damage and functional outcomes.

Secretome from hypoxia-conditioned adipose-derived mesenchymal stem cells promotes the healing of gastric mucosal injury in a rodent model.

Studies have indicated that the definitive engraftment and transdifferentiation potential of stem cells do not seem crucial for its property of tissue repair. Our previous study showed that transplantation of adipose-derived mesenchymal stem cells (ADMSCs) enhanced the healing of sutured gastric perforation. This study aimed to investigate the paracrine role of ADMSCs in the experimental gastric mucosal injury. Normoxia-conditioned medium (Nor CM) and hypoxia (HPO) CM were obtained after culturing ADMSCs in 20% O2 and 5% O2 for 48h. Cell migration, proliferation, viability, and angiogenesis in vitro were significantly enhanced upon incubation with CM, especially the HPO CM. Experiments in vivo using a rodent model of gastric ulcer demonstrated that HPO CM treatment significantly accelerated wound healing by suppressing inflammation and promoting neovascularization and re-epithelization. Meanwhile, the infusion of HPO CM activated the COX2-PGE2 axis both in vitro and in vivo. And the upregulation of COX2 was further dependent on the activation of ErK1/2-MAPK pathway. In addition, vascular endothelial growth factor, tissue inhibitors of metalloproteinases-1, and chemokine (C-C motif) ligand 20 (CCL-20) were analyzed as being highly abundant factors secreted by ADMSCs under hypoxic condition. Notably, the blockade of CCL-20 abrogated the HPO CM-induced COX2 signaling in the primary gastric mucosal epithelial cells, while incubation with recombinant CCL-20 increased the expression of COX2. In conclusion, the secretome from hypoxia-conditioned ADMSCs facilitates the repair of gastric mucosal injury through the enhancement of angiogenesis and re-epithelization, as well as the activation of COX2-PGE2 axis with a paracrine activity involving CCL-20 factor.

The aqueous extract of rhizome of Gastrodia elata Blume attenuates locomotor defect and inflammation after traumatic brain injury in rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Traumatic brain injury (TBI) has an incident rate of 200-300 people per 100,000 annually in the developed countries. TBI has relatively high incidence at an early age and may cause long-term physical disability. Patients suffered from severe TBI would have motor and neuropsychological malfunctions, affecting their daily activities. Traditionally, Gastrodia elata Blume is a Chinese Medicines which was used for the head diseases, while their efficiency on reducing brain damage was still largely unknown. In the present study, we aimed to examine the effect of water extract of G. elata Blume (GE) against TBI and elucidate its underlying mechanism. MATERIALS AND METHODS: Sprague-Dawley rats were treated with GE for 7 days, immediately after controlled cortical impact-induced TBI. Impaired neurobehavioral functioning was measured on day 3 and 6 after TBI. Histology of TBI was examined to assess the extent of inflammation, and the expressions of pro-inflammatory cytokines were examined by immunofluorescence study on day 7. RESULTS: GE treatment significantly improved the impaired locomotor functions induced by TBI. GE treatment reduced inflammation and gliosis in the penumbral area. The increase in brain levels of pro-inflammatory cytokines interleukin-6 and tumor necrosis factor-alpha observed in non-GE treated TBI rats were also reversed. CONCLUSIONS: GE treatment attenuated the locomotor deficit caused by TBI. The anti-inflammatory activity might be mediated by inhibition of pro-inflammatory cytokines responses in the TBI-brain.

Applications of exogenous mesenchymal stem cells and low intensity pulsed ultrasound enhance fracture healing in rat model.

The present study aimed to investigate the effects of combined treatment of exogenous mesenchymal stem cells (MSCs) and low intensity pulsed ultrasound (LIPUS) on fracture healing by comparing LIPUS-MSC, MSC and control (CTL) groups. Radiography and quantitative callus width/area demonstrated that the MSC-LIPUS group had the best healing, MSC group the second and CTL group the poorest with significant differences among each at different time points. Micro-CT data supported that MSC-LIPUS had the highest bone volume/tissue volume. Histomorphometry showed a significantly faster remodeling in late phase in MSC-LIPUS and MSC groups. These indicated that the combined treatment of MSCs and LIPUS was beneficial to fracture healing. Regenerative power and homing ability of MSCs were shown by promotion in fracture healing and locally found green fluorescent protein (GFP)-labeled MSCs at fracture calluses. This evidence reflects that co-treatment of MSCs and LIPUS may be developed as an intervention for delayed union or nonunion.

Low intensity pulsed ultrasound enhances fracture healing in both ovariectomy-induced osteoporotic and age-matched normal bones.

Low intensity pulsed ultrasound (LIPUS) was proven to enhance fracture healing effectively. Similar effect of LIPUS on accelerating the osteoporotic fracture healing was therefore hypothesized. The normal and osteoporotic fracture healings under this non-invasive biophysical intervention of LIPUS were compared and investigated. Closed femoral fracture procedures were performed on 120 Sprague-Dawley rats, in which 60 of them were ovariectomized (OVX). The rats were randomly assigned into four groups: sham OVX with treatment (Sham-T), sham OVX control (Sham-C), OVX with treatment (OVX-T) and OXV control (OVX-C). LIPUS treatment was 20 min a day, 5 days a week for durations of 2, 4, or 8 weeks. Results from weekly radiography, histomorphometry, micro-computed tomography and mechanical test showed both the treatment groups were with better healing responses than their control groups. Moreover, between the normal and the osteoporotic treatment groups, a significantly higher (p = 0.015) callus width (week 4), higher ratio of increment in bone volume to tissue volume ratio value (7.4% more), faster response of endochondral ossification and a higher stiffness measurement were observed in the osteoporotic treatment group. These comparable results on healing responses imply that LIPUS can be applied clinically to enhance both normal and osteoporotic fracture healing.