scholarly journals Cooperation between liver-specific mutations of pten and tp53 genetically induces hepatocarcinogenesis in zebrafish

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Juanjuan Luo ◽  
Chunjiao Lu ◽  
Meilan Feng ◽  
Lu Dai ◽  
Maya Wang ◽  
...  
Keyword(s):  
Poor Prognosis ◽  
Signalling Pathways ◽  
Transgenic Zebrafish ◽  
Single Mutation ◽  
Akt Inhibitor ◽  
Significant Similarity ◽  
Pten Loss ◽  
Tumour Formation ◽  
Low Efficiency ◽  
Genetic Events

Abstract Background Liver cancer, mainly hepatocellular carcinoma, is one of the deadliest cancers worldwide and has a poor prognosis due to insufficient understanding of hepatocarcinogenesis. Previous studies have revealed that the mutations in PTEN and TP53 are the two most common genetic events in hepatocarcinogenesis. Here, we illustrated the crosstalk between aberrant Pten and Tp53 pathways during hepatocarcinogenesis in zebrafish. Methods We used the CRISPR/Cas9 system to establish several transgenic zebrafish lines with single or double tissue-specific mutations of pten and tp53 to genetically induce liver tumorigenesis. Next, the morphological and histological determination were performed to investigate the roles of Pten and Tp53 signalling pathways in hepatocarcinogenesis in zebrafish. Results We demonstrated that Pten loss alone induces hepatocarcinogenesis with only low efficiency, whereas single mutation of tp53 failed to induce tumour formation in liver tissue in zebrafish. Moreover, zebrafish with double mutations of pten and tp53 exhibits a much higher tumour incidence, higher-grade histology, and a shorter survival time than single-mutant zebrafish, indicating that these two signalling pathways play important roles in dynamic biological events critical for the initiation and progression of hepatocarcinogenesis in zebrafish. Further histological and pathological analyses showed significant similarity between the tumours generated from liver tissues of zebrafish and humans. Furthermore, the treatment with MK-2206, a specific Akt inhibitor, effectively suppressed hepatocarcinogenesis in zebrafish. Conclusion Our findings will offer a preclinical animal model for genetically investigating hepatocarcinogenesis and provide a useful platform for high-throughput anticancer drug screening.

Neuroinflammation, diabetes, and COVID-19: Perspectives coming from Ca2+/cAMP signalling

2021 ◽  
Vol 14 ◽  
Author(s):  
Leandro Bueno Bergantin
Keyword(s):  
Observational Studies ◽  
Poor Prognosis ◽  
Inflammatory Diseases ◽  
Signalling Pathways ◽  
Camp Signalling ◽  
People With Dementia ◽  
Bidirectional Relationship ◽  
Patients With Diabetes ◽  
Clinical Relationship

Background: A link between inflammatory diseases, e.g., epilepsy, dementia, diabetes, and COVID-19, has been established. For instance, observational studies with several individuals established that people with epilepsy have shown an enhanced incidence of manifesting dysfunctions related to cognition, e.g., dementia, while people with dementia have a higher incidence of manifesting epilepsy, thus an evident bidirectional relationship between epilepsy and dementia might occur. In addition, epilepsy commonly cooccurs in patients with diabetes, so an association between these two disorders is also discussed. Intriguingly, some reports have also observed a poor prognosis for people with both diabetes and COVID-19. It is recognized that a dyshomeostasis of both Ca2+ and cAMP signalling pathways could be a molecular connection for these disorders. Objectives: Therefore, clarifying this clinical relationship among epilepsy, dementia, diabetes, and COVID-19 may outcome in novel hypotheses for identifying the etiology of these disorders.

Circulating tumor cell (CTC) detection, N-terminal androgen (AR) characterization, and PTEN loss in metastatic or advanced castration resistant prostate cancer (CRPC).

2016 ◽  
Vol 34 (2_suppl) ◽  
pp. 195-195
Author(s):  
Shidong Jia ◽  
Sarah Baird ◽  
Amanda K. L. Anderson ◽  
Shannon L. Werner ◽  
Jane Petersen ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Circulating Tumor Cell ◽  
Response To Therapy ◽  
Castration Resistant Prostate Cancer ◽  
Akt Inhibitor ◽  
Patient Response ◽  
Invasive Approach ◽  
Disease Evolution ◽  
Pten Loss ◽  
Non Invasive

195 Background: Detection and characterization of CTCs offers a minimally invasive mechanism for understanding patient response to therapy and disease evolution. Here we describe a proprietary technology platform to examine CTC incidence, N-terminal AR expression, and PTEN loss in metastatic or advanced CRPC patient samples from a phase II clinical trial (GO27983) testing the combination of the AKT inhibitor ipatasertib and abiraterone. Methods: Blood samples from CRPC patients (n = 283) were collected at screening and shipped to Epic Sciences. Upon receipt, the nucleated cells were plated onto microscope slides and stored at -80C. Two slides were thawed per patient and analyzed with an N-terminal AR CTC assay. CTCs were detected using a combination of CD45 exclusion, CK and N-terminal AR expression, and morphologic criteria. Traditional (CD45-, CK+, DAPI+) and Non-Traditional (CD45-/CK- with distinct morphology or CD45-/CK+ with fragmented nuclei) CTCs were enumerated and N-terminal AR expression was quantified for each CTC. Samples with > 2 Traditional CTCs enumerated per slide were further evaluated for PTEN loss by FISH (n = 170). Results: Traditional CTCs were detected ( ≥ 1 cell/ml) in 86% (242 of 283) of samples. Non-traditional CTCs were detected in 93% (263 of 283) of patients. N-terminal AR positivity was detected ( ≥ 1 AR+ cell/ml) in 53% (128 of 242) of Traditional CTC-positive samples, with the % positivity ranging from 0.4-100%. PTEN status was determined for 66% (160 of 243) of patients with Traditional CTCs detected. Patients with homozygous (HO) PTEN loss had a significantly higher mean CTC/mL (p = 0.0013) and AR+ CTC/mL value (p = 0.0014) than patients with PTEN non-deleted status. Conclusions: The ability of the Epic Sciences platform to detect AR+ CTCs and PTEN loss at screening provides a non-invasive approach to characterizing and monitoring CTCs identified in advanced CRPC patients. The study is ongoing to monitor longitudinal changes in CTC incidence and AR expression in relation to PTEN status. Clinical trial information: NCT01485861.

124. Regulation of SOCS3 expression by prostaglandin, prolactin and growth hormone: challenging the Jak/STAT signalling dogma

2005 ◽  
Vol 17 (9) ◽  
pp. 74
Author(s):  
J. L. Barclay ◽  
T. Wonisch ◽  
S. T. Anderson ◽  
M. J. Waters ◽  
J. D. Curlewis
Keyword(s):  
Fold Increase ◽  
Signalling Pathways ◽  
Akt Inhibitor ◽  
Akt Phosphorylation ◽  
Jak2 Inhibitor ◽  
Receptor Signalling ◽  
Socs3 Expression ◽  
Cellular Responsiveness ◽  
Responsive Element ◽  
Socs3 Mrna

SOCS3 is an inhibitor of various cytokine-receptor signalling pathways and is therefore involved in suppression of cellular responsiveness to these critical regulators. SOCS3 expression is thought to be regulated by a STAT responsive element (SRE). However, our research suggests the involvement of other signalling pathways. In T-47D breast cancer cells, we found that PGE2 induces a 3–5 fold increase in SOCS3 mRNA, as determined by real-time PCR. This effect was not due to phosphorylation of STATs, or inhibited by the Jak2 inhibitor, AG490, but was inhibited by the PI3Kinase inhibitor, LY294002, Akt Inhibitor IV and partially inhibited by the PKA inhibitor, H89. It was not affected by inhibitors of MEK, PDK1, mTOR or p38-MAPK. We concurrently examined PRL-induced SOCS3 expression, and found that although STAT1 and 5 phosphorylation was increased, SOCS3 expression was again inhibited by Akt Inhibitor IV and H89 but unaffected by AG-490. To explore this further, we used a model of GH signalling, BaF3 cells stably expressing GH receptor. GH induced a 15–20 fold increase in SOCS3 mRNA, which was accompanied by increased STAT5 phosphorylation. However the SOCS3 response was not inhibited by AG-490 or H89, but was diminished by Akt Inhibitor IV. Analysis of the SOCS3 promoter revealed a FOXO binding site. When we mutated this site in a mouse SOCS3 promoter–luciferase construct, basal and GH-induced promoter activity was significantly increased. These results are consistent with FOXO acting as a repressor, which is inactivated by Akt. We propose that in T-47D cells, SOCS3 expression involves cross-talk between PI3K/Akt and cAMP/PKA, whereas in BaF3 cells, expression is enhanced by Akt phosphorylation and subsequent FOXO inactivation. These findings contrast with the accepted Jak/STAT regulation of SOCS3 expression. This work is supported by the Australian Research Council.

First-in-Man Clinical Trial of the Oral Pan-AKT Inhibitor MK-2206 in Patients With Advanced Solid Tumors

2011 ◽  
Vol 29 (35) ◽  
pp. 4688-4695 ◽  
Author(s):  
Timothy A. Yap ◽  
Li Yan ◽  
Amita Patnaik ◽  
Ivy Fearen ◽  
David Olmos ◽  
...  
Keyword(s):  
Solid Tumors ◽  
Skin Rash ◽  
Maximum Tolerated Dose ◽  
Akt Signaling ◽  
Hair Follicles ◽  
Advanced Solid Tumors ◽  
Akt Inhibitor ◽  
Time Curve ◽  
Pten Loss ◽  
Tumor Biopsies

Purpose AKT signaling is frequently deregulated in human cancers. MK-2206 is a potent, oral allosteric inhibitor of all AKT isoforms with antitumor activity in preclinical models. A phase I study of MK-2206 was conducted to investigate its safety, maximum-tolerated dose (MTD), pharmacokinetics (PKs), pharmacodynamics (PDs), and preliminary antitumor efficacy. Patients and Methods Patients with advanced solid tumors received MK-2206 on alternate days. Paired tumor biopsies were mandated at the MTD for biomarker studies. PD studies incorporated tumor and hair follicle analyses, and putative predictive biomarker studies included tumor somatic mutation analyses and immunohistochemistry for phosphatase and tensin homolog (PTEN) loss. Results Thirty-three patients received MK-2206 at 30, 60, 75, or 90 mg on alternate days. Dose-limiting toxicities included skin rash and stomatitis, establishing the MTD at 60 mg. Drug-related toxicities included skin rash (51.5%), nausea (36.4%), pruritus (24.2%), hyperglycemia (21.2%), and diarrhea (21.2%). PKs (area under the concentration-time curve from 0 to 48 hours and maximum measured plasma concentration) were dose proportional. Phosphorylated serine 473 AKT declined in all tumor biopsies assessed (P = .015), and phosphorylated threonine 246 proline-rich AKT substrate 40 was suppressed in hair follicles at 6 hours (P = .008), on days 7 (P = .028) and 15 (P = .025) with MK-2206; reversible hyperglycemia and increases in insulin c-peptide were also observed, confirming target modulation. A patient with pancreatic adenocarcinoma (PTEN loss; KRAS G12D mutation) treated at 60 mg on alternate days experienced a decrease of approximately 60% in cancer antigen 19-9 levels and 23% shrinkage in tumor measurements. Two patients with pancreatic neuroendocrine tumors had minor tumor responses. Conclusion MK-2206 was well tolerated, with evidence of AKT signaling blockade. Rational combination trials are ongoing to maximize clinical benefit with this therapeutic strategy.

Anti-Apoptotic Signal Transduction Mechanism of Electroacupuncture in Acute Spinal Cord Injury

2014 ◽  
Vol 32 (6) ◽  
pp. 463-471 ◽  
Author(s):  
Quan Renfu ◽  
Chen Rongliang ◽  
Du Mengxuan ◽  
Zhang Liang ◽  
Xu Jinwei ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Intrathecal Injection ◽  
Signalling Pathways ◽  
Spinal Cord Tissue ◽  
Akt Inhibitor ◽  
Apoptotic Pathway ◽  
Tissue Samples ◽  
Spinal Cord Segment ◽  
Cord Injury

Spinal cord injury (SCI) can be caused by a variety of pathogenic factors. In China, acupuncture is widely used to treat SCI. We previously found that acupuncture can reduce apoptosis and promote repair after SCI. However, the antiapoptotic mechanisms by which acupuncture exerts its effects on SCI remain unclear. Our aim was to investigate the role of the PI3K/Akt and extracellular signal-regulated kinases (ERK)1/2 signalling pathways in acupuncture treatment of acute SCI. Eighty pure-bred New Zealand rabbits were randomly divided into the following five groups (n=16 per group): control; model; elongated needle electroacupuncture (EA); EA+LY294002; and EA+PD98059. We established a spinal cord contusion model of SCI in all experimental groups except controls, in which only a laminectomy was performed. After SCI, three of the groups received EA once daily for 3 days. One hour before SCI, the two drug groups received LY294002 (Akt inhibitor; 10 μg, 20 μL) or PD98059 (ERK inhibitor; 3 μg, 20 μL) via intrathecal injection. At 48 h after SCI, animals were killed and spinal cord tissue samples were collected for transferase dUTP nick end labelling (TUNEL) assays, immunohistochemistry and western blot assays. EA significantly increased p-Akt and p-ERK1/2 expression, reduced cytochrome c and caspase-3 expression and inhibited neuronal apoptosis in the injured spinal cord segment. The opposite effects were seen after using Akt and ERK inhibitors. Acupuncture promotes the repair of SCI, possibly by activation of the PI3K/Akt and ERK1/2 signalling pathways and by inhibition of the mitochondrial apoptotic pathway.

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