ASXL3 gene mutations inhibit cell proliferation and promote cell apoptosis in mouse cardiomyocytes by upregulating lncRNA NONMMUT063967.2

Congenital heart disease (CHD) is a serious condition with unknown etiology. In a recent study, a compound heterozygous mutation (c.3526C > T [p.Arg1176Trp] and c.4643A > G [p.Asp1548Gly]) in the ASXL3 gene was identified, which is associated with CHD. This mutation was overexpressed in HL-1 mouse cardiomyocyte cells, leading to increased cell apoptosis and decreased cell proliferation. However, whether this effect is mediated by long noncoding RNAs (lncRNAs) is yet to be determined. We identified the differences among lncRNA and mRNA profiles in mouse heart tissues using sequencing to explore this issue. We detected HL-1 cell proliferation and apoptosis through CCK8 and flow cytometry. Fgfr2, lncRNA, and Ras/ERK signaling pathway expressions were evaluated using quantitative real time polymerase chain reaction (qRT-PCR) and western blot (WB) assays. We also conducted functional investigations by silencing lncRNA NONMMUT063967.2. The sequencing revealed significant changes in lncRNA and mRNA profiles, with the expression of lncRNA NONMMUT063967.2 being significantly promoted in the ASXL3 gene mutations group (MT) while the expression of Fgfr2 being downregulated. The in vitro experiments showed that ASXL3 gene mutations inhibited the proliferation of cardiomyocytes and accelerated cell apoptosis by promoting the expression of lncRNAs (NONMMUT063967.2, NONMMUT063918.2, and NONMMUT063891.2), suppressing the formation of FGFR2 transcripts, and inhibiting the Ras/ERK signaling pathway. The decrease in FGFR2 had the same effect on the Ras/ERK signaling pathway, proliferation, and apoptosis in mouse cardiomyocytes as ASXL3 mutations. Further mechanistic studies revealed that suppression of lncRNA NONMMUT063967.2 and overexpression of FGFR2 reversed the effects of the ASXL3 mutations on the Ras/ERK signaling pathway, proliferation, and apoptosis in mouse cardiomyocytes. Therefore, ASXL3 mutation decreases FGFR2 expression by upregulating lncRNA NONMMUT063967.2, inhibiting cell proliferation and promoting cell apoptosis in mouse cardiomyocytes.

Hericium erinaceus polysaccharide improves the microstructure, immune function, proliferation and reduces apoptosis of thymus and spleen tissue cells of immunosuppressed mice

In order to study the effect of Hericium erinaceus polysaccharide (HEP) on the immune and antioxidation functions of immunosuppressed mice. The control group received distilled water orally and the model and experimental groups I, II, and III received 0, 80, 160, and 320 mg/kg HEP respectively for a fortnight after re-molding with cyoclphosphnalide (CTX). Compared with the control group, the secretion of IL-2, IL-4, and IFN-γ, the activity or content of T-AOC, T-SOD, and GSH-PX, and the expression of PCNA mRNA in the thymus and spleen were reduced in immunosuppressed mice (P < .05 or P < .01). Compared with immunosuppressed mice, the levels of IL-2, IFN-γ, and GSH-PX and the PCNA mRNA expression of spleen and thymus were increased (P < .05 or P < .01), and the microstructure were also obviously improved in the experimental group III. Overall, 320 mg/kg of HEP significantly improved the immune and antioxidant functions.

miR-27a Targeting PIK3R3 Regulates the Proliferation and Apoptosis of Sheep Hair Follicle Stem Cells

Micro RNAs are regulatory factors in tissue development, organ formation, cell growth, apoptosis and other biological processes. In particular, several miRNAs are related to the development of hair follicles. Here, we investigated the effect of the targeting of PIK3R3 by miR-27a on the AKT/MTOR pathway and on the proliferation and apoptosis of hair follicle stem cells (HFSCs) in sheep. Knockdown of the expression of PIK3R3 was found to significantly inhibit the proliferation and promote the apoptosis of HFSCs. Similarly, a miR-27a mimic significantly inhibited the proliferation and promoted the apoptosis of HFSCs. The miR-27a mimic was also shown to significantly inhibit the expression of PIK3R3, AKT, and MTOR and the phosphorylation of AKT and MTOR, while a miR-27a inhibitor increased the expression of these genes. The presence of an miR-27a binding site in the 3' UTR of PIK3R3 was identified by a bioinformatics analysis, and the interaction was verified with a dual-luciferase reporter assay. The expression of PIK3R3 mRNA and protein was negatively correlated with the presence of miR-27a, which suggests that this interaction may be involved in the biological impacts on proliferation and apoptosis. Thus, this study demonstrates that miR-27a plays a potential role in the proliferation and apoptosis of sheep hair follicle stem cells by targeting PIK3R3, which can be used to design new methods to improve sheep wool.

Characterization of Temozolomide Resistance Using a Novel Acquired Resistance Model in Glioblastoma Cell Lines

Simple Summary

Temozolomide (TMZ) is the first-line drug for chemotherapy of GBM, the most aggressive and incurable brain tumor. Acquired chemoresistance is a hallmark that causes the poor prognosis of GBM. Therefore, understanding the underlying mechanisms by using a proper model becomes emergent. Previous models usually take weeks/months and are often not fully representative of characteristics of TMZ resistance. We established an acute acquired TMZ resistance model using GBM cell lines with different genomic backgrounds. In response to TMZ, the resistant cells showed less susceptibility and sustained regrowth, high clonogenicity, reduced DNA damage accompanied by attenuated MMR, shortened G2/M arrest, uncontrolled DNA replication, and evasion of apoptosis. Moreover, these TMZ resistant cells presented stem cell properties that are critical for chemoresistance. Thus, our model recapitulates all key features of TMZ resistance and is believed to be a promising model to study the underlying mechanisms and define therapeutics for GBM in the future.

Abstract

Temozolomide (TMZ) is the first line of standard therapy in glioblastoma (GBM). However, relapse occurs due to TMZ resistance. We attempted to establish an acquired TMZ resistance model that recapitulates the TMZ resistance phenotype and the relevant gene signature. Two GBM cell lines received two cycles of TMZ (150 µM) treatment for 72 h each. Regrown cells (RG2) were defined as TMZ resistant cells. MTT assay revealed significantly less susceptibility and sustained growth of RG2 compared with parental cells after TMZ challenge. TMZ-induced DNA damage significantly decreased in 53BP1-foci reporter transduced-RG2 cells compared with parental cells, associated with downregulation of MSH2 and MSH6. Flow cytometry revealed reduced G2/M arrest, increased EdU incorporation and suppressed apoptosis in RG2 cells after TMZ treatment. Colony formation and neurosphere assay demonstrated enhanced clonogenicity and neurosphere formation capacity in RG2 cells, accompanied by upregulation of stem markers. Collectively, we established an acute TMZ resistance model that recapitulated key features of TMZ resistance involving impaired mismatch repair, redistribution of cell cycle phases, increased DNA replication, reduced apoptosis and enhanced self-renewal. Therefore, this model may serve as a promising research tool for studying mechanisms of TMZ resistance and for defining therapeutic approaches to GBM in the future.

Circular RNA hsa_circ_0032683 inhibits the progression of hepatocellular carcinoma by sponging microRNA-338-5p

Recently, several studies have been conducted on circRNA (circular RNA). circRNA regulates gene expression and plays a vital role in the occurrence and development of various tumors. However, the role and mechanism of hsa_circ_0032683 in hepatocellular carcinoma (HCC) is not studied yet. In GEO (Gene Expression Omnibus) database, hsa_circ_0032683 expression was significantly lower in HCC tissues than in normal liver tissues. In vitro and in vivo functional tests revealed that hsa_circ_0032683 could inhibit HCC cells proliferation and promote their apoptosis. Mechanically, hsa_circ_0032683 primarily exists in the cytoplasm and competes with microRNA-338-5p (miR-338-5p) to regulate reticulon 4(RTN4). Our experiments revealed that hsa_circ_0032683 receded the proliferation ability of HCC via ceRNA (competing endogenous RNAs) mechanism, which provided potential biomarkers and therapeutic targets for HCC patients.Abbreviations: circRNAs: circular RNA; HCC: hepatocellular carcinoma; RTN4: reticulon 4; ceRNA: competing endogenous RNA; GEO: Gene Expression Omnibus; miRNA: microRNA; CSCD: Cancer-specific circRNA database; CRI: Circular RNA Interactome; TCGA: The Cancer Genome Atlas; qRT-PCR: quantitative real-time PCR; NEK9:NIMA-related kinase nine; CSMD1: CUB and Sushi multiple domains 1; Tob1: transducer of ERBB2, 1; miR: microRNA; sh: short hairpin; WT: wild type; MUT: mutant.

Effect of miRNA-136-targeted regulation of FGFR1 on proliferation and apoptosis of triple-negative breast cancer cells

PURPOSE

This study was designed to investigate the effect of micro RNA-targeted regulation of FGFR1 on the proliferation and apoptosis of triple-negative breast cancer (TNBC) cells.

METHODS

TNBC (MAD-MB-231), three types of breast cancer (MCF10A, MCF7, ZR751) cell lines, and normal breast tissue cell lines were extracted. Real-time PCR was used to detect the expression of miRNA-136 in different types of breast cells. The MAD-MB-231 cell lines were transfected with miRNA-136 mimic by lipofection. The effects of miRNA-136 on FGFR1 expression and apoptosis rate of MAD-MB-231 cell lines were determined using western blotting.

RESULTS

miRNA-136 expression in TNBC cells was lower than that of controls, and was negatively correlated with TNM staging. miRNA-136 expression in MCF10A, MCF7, ZR751, and MAD-MB-231 cell lines was gradually decreased, and MCF10A expression in the other three cell lines was significantly higher than that of MAD-MB-231 cell line (P<0.05). Transfection with miRNA-136 significantly reduced the proliferation rate of MAD-MB-231, and a higher concentration and longer duration exhibited a more pronounced inhibitory effect on proliferation (P<0.05). Transfection with miRNA-136 significantly reduced FGFR1 expression in the MAD-MB-231 cell lines, without significantly affecting apoptosis.

CONCLUSION

miRNA-136 shows a very low expression level in TNBC cells. Transfection with miRNA-136 can significantly inhibit the proliferation of TNBC cells by external transfection, and has little effect on cell apoptosis. This may be related to miRNA-mediated changes in FGFR1 protein expression.

Repositioning of Hypoglycemic Drug Linagliptin for Cancer Treatment

Background

Drug repositioning, development of new uses for marketed drugs, is an effective way to discover new antitumor compounds. In this study, we used a new method, filtering compounds via molecular docking to find key targets combination.

Methods

The data of gene expression in cancer and normal tissues of colorectal, breast, and liver cancer were obtained from The Cancer Genome Atlas Project (TCGA). The key targets combination was obtained from the protein-protein interaction network (PPI network) and the correlation analysis of the targets. Molecular docking was used to reposition the drugs which were obtained from DrugBank. MTT proliferation assay and animal experiments were used to verify the activity of candidate compounds. Flow cytometric analysis of proliferation, cell cycle and apoptosis, slice analysis, gene regulatory network, and Western blot were performed to elucidate the mechanism of drug action.

Results

CDK1 and AURKB were identified as a pair of key targets by the analysis of different expression gene from TCGA. Three compounds, linagliptin, mupirocin, and tobramycin, from 12 computationally predicted compounds, were verified to inhibit cell viability in HCT116 (colorectal), MCF7 (breast), and HepG2 (liver) cancer cells. Linagliptin, a hypoglycemic drug, was proved to inhibit cell proliferation by cell cycle arrest and induce apoptosis in HCT116 cells, and suppress tumor growth in nude mice bearing HCT116 cells. Linagliptin reduced the tumor size and decreased the expression of Ki67, a nuclear protein expressed in all proliferative cells. Gene regulatory network and Western blot analysis suggested that linagliptin inhibited tumor cell proliferation and promoted cell apoptosis through suppressing the expression and phosphorylation of Rb, plus down-regulating the expression of Pro-caspase3 and Bcl-2, respectively.

Conclusion

The combination of key targets based on the protein-protein interaction network that were built by the different gene expression of TCGA data to reposition the marketed drugs turned out to be a new approach to discover new antitumor drugs. Hypoglycemic drug linagliptin could potentially lead to novel therapeutics for the treatment of tumors, especially for colorectal cancer. Gene regulatory network is a valuable method for predicting and explaining the mechanism of drugs action.

Circular RNA ABCB10 correlates with advanced clinicopathological features and unfavorable survival, and promotes cell proliferation while reduces cell apoptosis in epithelial ovarian cancer

OBJECTIVE

This study aimed to explore the correlation of circular RNA ABCB10 (circ-ABCB10) expression with clinicopathological features and survival, as well as its impact on regulating cell proliferation and apoptosis in epithelial ovarian cancer (EOC).

METHODS

A total of 103 EOC patients were consecutively recruited, then their tumor tissues were obtained for circ-ABCB10 detection using qRT-PCR. Additionally, 53 EOC adjacent tissues were collected as control. Patients' clinicopathological and survival data were recorded. In vitro, circ-ABCB10 expression was detected in OVCAR3, UWB1.289, SKOV3, CAOV3 and IOSE80 cell lines by RT-qPCR, and the effect of circ-ABCB10 on cell proliferation and apoptosis was detected through circ-ABCB10 overexpression and silencing by plasmids transfection into SKOV3 cells.

RESULTS

Circ-ABCB10 was upregulated in tumor tissues compared with adjacent tissues, and presented with good value in distinguishing tumor tissues from adjacent tissues (AUC = 0.766, 95% CI: 0.690-0.842). Circ-ABCB10 high expression was correlated with poor differentiation, large tumor size and advanced International Federation of Gynecology and Obstetrics (FIGO) stage in EOC patients. As for survival, circ-ABCB10 was correlated with worse OS. In vitro experiments revealed that circ-ABCB10 was upregulated and promoted cell proliferation but reduced cell apoptosis, and negatively regulated miR-1271, miR-1252 and miR-203 in EOC cells.

CONCLUSIONS

Circ-ABCB10 correlates with advanced clinicopathological features and unfavorable survival, and promotes proliferation, reduces apoptosis and negatively regulated miR-1271, miR-1252 and miR-203 in EOC.

P65 Targets FGFR1 to Regulate the Survival of Ovarian Granulosa Cells

In female mammals, the abnormal apoptosis of ovarian granulosa cells (GCs) impairs follicular development and causes reproductive dysfunction. Many studies have indicated that the FGFR1 gene of the PI3K signaling pathway and the p65 subunit of the transcription factor NF-κB may regulate the proliferation and apoptosis of GCs involved in follicular development. However, little is known about whether p65 regulates the transcription of FGFR1, as well as the biological effects of p65 and FGFR1 on the survival of GCs and follicular development. In porcine follicles and GCs, we found that p65 and FGFR1 were exclusively expressed in the GCs of follicles, and the mRNA and protein levels of p65 and FGFR1 significantly increased from small to large follicles. Both p65 and FGFR1 were found to activate the PI3K signaling pathway, and the expressions of proliferation markers (PCNA and MKI67) and the anti-apoptotic gene BCL2 were significantly increased by p65 and FGFR1. Furthermore, both p65 and FGFR1 were observed to promote cell proliferation and inhibit the cell apoptosis of GCs, and p65 was confirmed to bind at the −348/−338 region of FGFR1 to positively regulate its transcription. Moreover, p65 was further found to enhance the pro-proliferation and anti-apoptotic effects of FGFR1. Taken together, p65 may target the −348/−338 region of FGFR1, promote the transcription of FGFR1, and enhance the pro-proliferation effect and anti-apoptotic effect of FGFR1 to facilitate the growth of follicles. This study will provide useful information for further investigations on the p65-mediated-FGFR1 signaling pathway during folliculogenesis in mammals.

Discovery and Characterization of 4-Hydroxy-2-pyridone Derivative Sambutoxin as a Potent and Promising Anticancer Drug Candidate: Activity and Molecular Mechanism

Sambutoxin, a representative derivative of 4-hydroxy-2-pyridone, was isolated from Hericium alpestre for the first time in this study. The possible correlation between the sambutoxin-induced suppression of tumor growth and its influence on cell-cycle arrest and apoptosis was investigated. The effects of sambutoxin on reactive oxygen species (ROS) production, DNA damage, mitochondrial transmembrane potential, cell apoptosis, and the expression of related proteins were evaluated. An in vitro cell viability study demonstrated that sambutoxin could inhibit the proliferation of various cancer cells. Treatment with sambutoxin induced the production of ROS, which caused DNA damage. Furthermore, the subsequent sambutoxin-induced activation of ATM and Chk2 resulted in G2/M arrest, accompanied by decreased expression of cdc25C, cdc2, and cyclin B1. Sambutoxin induced apoptosis by activating the mitochondrial apoptosis pathway through an increased Bax/Bcl-2 ratio, loss of mitochondrial membrane potential (ΔΨm), cytochrome (Cyt) c release, caspase-9 and caspase-3 activation, and poly(ADP-ribose) polymerase (PARP) degradation. The ROS elevation induced the sustained phosphorylation of c-Jun N-terminal kinase (JNK), while SP600125, a JNK inhibitor, nearly completely reversed sambutoxin-induced apoptosis. Accordingly, an in vivo study showed that sambutoxin exhibited potential antitumor activity in a BALB/c nude mouse xenograft model without significant systemic toxicity. Moreover, the expression changes in proteins related to the G2/M phase, DNA damage, and apoptosis in vivo were consistent with those in vitro. Importantly, sambutoxin has remarkable antiproliferative effects and is a promising anticarcinogen candidate for cancer treatment.

Interleukin-6 induced overexpression of valosin-containing protein (VCP)/p97 is associated with androgen-independent prostate cancer (AIPC) progression

Though Androgen deprivation therapy (ADT) is effective initially, numerous patients become resistant to it and develop castration resistant PCa (CRPC). Cytokines promotes ligand independent activation of AR. Interleukin-6 (IL-6) levels are elevated in CRPC patients and regulate AR activity. However, progression to CRPC is not fully understood. In this study, we analyzed differential protein expression in LNCaP cells treated with IL-6 using proteomics. Results revealed altered expression of 27 proteins and Valosin-containing protein (VCP)/p97 plays a predominant role in co-regulation of altered proteins. Interestingly, IL-6 induced VCP expression through Pim-1 via STAT3 is AR independent there by suggesting a role for VCP in CRPC. Transfection of LNCaP cells for VCP overexpression showed an increased cell proliferation, migration, and invasion where as its inhibition by NMS-873 showed the reverse effect causing cell death. Mechanistic studies demonstrate that cell death occurs due to apoptosis by endoplasmic reticulum (ER) stress, elevated cell cycle inhibitors p21, p27kip1, and active PARP and reduced Bcl-2. VCP promotes cell invasion and migration by altering E-cadherin and Vimentin levels inversely triggering EMT of PCa cells. VCP immunostaining revealed no staining in BPH but strong staining in PCa. This study determines VCP may play an important role in progression to CRPC and it can be a favorable target with to develop new therapies to treat ADT resistant prostate cancer.

Polydopamine-collagen complex to enhance the biocompatibility of polydimethylsiloxane substrates for sustaining long-term culture of L929 fibroblasts and tendon stem cells

Polydimethylsiloxane (PDMS) is a commercialized polymer extensively used in the fabrication of versatile microfluidic microdevices for studies in cell biology and tissue engineering. However, the inherent surface hydrophobicity of PDMS is not optimal for cell culture and thus restrains its applications for investigation of long-term behaviors of fibroblasts and stem cells. To improve the surface biocompatibility of PDMS, a facile technique was developed by modifying the PDMS surface with polydopamine-collagen (COL/PDA) complex. The successful synthesis of COL/PDA was verified through proton nuclear magnetic resonance spectroscopy. Compared to surface coating solely with COL or PDA, the surface wettability was significantly improved on COL/PDA-modified PDMS substrates based on water contact angle characterizations. The modified PDMS surface remarkably enhanced the initial adhesion and long-term proliferation of L929 fibroblasts and tendon stem cells (TSCs). Additionally, the effects of COL/PDA coating on cell viability and apoptosis were further investigated under prolonged incubation. We found that the COL/PDA coating on PDMS resulted in a substantial increase of cell viability compared to native PDMS, and the cell apoptosis was considerably impeded on the modified PDMS. This study demonstrated that COL/PDA coating can effectively enhance the surface biocompatibility of PDMS as verified by the enhanced adhesion and long-term proliferation of L929 fibroblasts and TSCs. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 408-418, 2018.

Emerging roles of RAC1 in treating lung cancer patients

The Ras-related C3 botulinum toxin substrate 1 (RAC1), a member of the Rho family of small guanosine triphosphatases, is critical for many cellular activities, such as phagocytosis, adhesion, migration, motility, cell proliferation, and axonal growth. In addition, RAC1 plays an important role in cancer angiogenesis, invasion, and migration, and it has been reported to be related to most cancers, such as breast cancer, gastric cancer, testicular germ cell cancer, and lung cancer. Recently, the therapeutic target of RAC1 in cancer has been investigated. In addition, some investigations have shown that inhibition of RAC1 can reverse drug-resistance in non-small cell lung cancer. In this review, we summarize the recent advances in understanding the role of RAC1 in lung cancer and the underlying mechanisms and discuss its value in clinical therapy.

Rrp15 affects cell cycle, proliferation, and apoptosis in NIH3T3 cells

Riken 2810430M08 (hereinafter referred to as Rrp15) is a newly identified and reported gene from the mouse genome. In our previous work, we found that the gene had a relationship with the proliferation and activation of T cells. Rrp15 protein is highly homologous with RRP15 (budding yeast), which has an important role in ribosomal RNA processing. We explored the potential function of Rrp15 in apoptosis, cell proliferation, and its involvement with RNA in the nucleus. We constructed a knockdown of the Rrp15 gene in NIH3T3 cells and then performed real-time PCR, western blotting, flow cytometry, and immunofluorescence to determine the function of the Rrp15 gene. Knockdown of the Rrp15 gene suppresses proliferation and induces apoptosis. We also found that the Rrp15 protein was normally distributed in the nucleus and bound to RNA or pre-RNA in the nucleus. Additionally, Rrp15 altered the activity of the 20S proteasome. Rrp15 promotes proliferation and inhibits apoptosis in NIH3T3 cells and may have a relationship with RNA in the nucleus.

Alpinetin inhibits lung cancer progression and elevates sensitization drug-resistant lung cancer cells to cis-diammined dichloridoplatium

OBJECTIVE

Alpinetin is a novel flavonoid that has demonstrated potent antitumor activity in previous studies. However, the efficacy and mechanism of alpinetin in treating lung cancer have not been determined.

METHODS

We evaluated the impact of different doses and durations of alpinetin treatment on the cell proliferation, the apoptosis of lung cancer cells, as well as the drug-resistant lung cancer cells.

RESULTS

This study showed that the alpinetin inhibited the cell proliferation, enhanced the apoptosis, and inhibited the PI3K/Akt signaling in lung cancer cells. Moreover, alpinetin significantly increased the sensitivity of drug-resistant lung cancer cells to the chemotherapeutic effect of cis-diammined dichloridoplatium. Taken together, this study demonstrated that alpinetin significantly suppressed the development of human lung cancer possibly by influencing mitochondria and the PI3K/Akt signaling pathway and sensitized drug-resistant lung cancer cells.

CONCLUSION

Alpinetin may be used as a potential compound for combinatorial therapy or as a complement to other chemotherapeutic agents when multiple lines of treatments have failed to reduce lung cancer.

Validation of Polo-like kinase 1 as a therapeutic target in pancreatic cancer cells

Polo-like kinase 1 (PLK1) is a serine/threonine protein kinase and plays a critical role in mitosis. PLK1 has also been regarded as a valuable target for cancer treatment, and several PLK1 inhibitors are currently undergoing clinical investigations. In this study, our data show that the expression level of PLK1 is upregulated in human pancreatic cancer cells. Molecular modeling studies indicate that DMTC inhibits PLK1 activity through competitive displacement of ATP from its binding pocket. Our data further show that DMTC suppresses the proliferation of pancreatic cancer cells and induces the formation of multinucleated cells, ultimately resulting in apoptosis. In addition, combination index analysis demonstrates that DMTC acts synergistically with the chemotherapeutic drug gemcitabine in inhibiting the proliferation of pancreatic cancer cells. These results thus suggest a potential of using PLK1 inhibitors for the treatment of pancreatic cancer.