ACTA BIOCHIMICA ET BIOPHYSICA SINICA

Repurposed genipin targeting UCP2 exhibits antitumor activity through inducing ferroptosis in glioblastoma
Dong H, Sun K, Wang X, Cui M, Ma Y, Li K, Duan W, Zhang H, Zhang L, Sheng Z, He M and Zhang B
Uncoupling protein-2 (UCP2) controls the antioxidant response and redox homeostasis in cancer and is considered a potent molecular target for cancer treatment. However, the specific mechanism of UCP2 inhibition and its role in glioblastoma (GBM) have not yet been elucidated. Here, we attempt to identify a UCP2 inhibitor and study the underlying molecular mechanism in GBM. Bioinformatics analysis and immunohistochemistry are used to validate the high expression of UCP2 in GBM and its prognostic significance. Drug intervention and tumor xenograft experiments are conducted to determine the inhibitory effect of genipin, a UCP2 inhibitor, on UCP2. The mitochondrial membrane potential and key ferroptosis genes are examined to determine the occurrence of ferroptosis. High expression of UCP2 in GBM is associated with poor prognosis, and inhibiting UCP2 can alleviate the malignant behavior of GBM tumors. Genipin can downregulate the expression of GPX4 and upregulate the expression of ACSL4 by inhibiting UCP2, leading to ferroptosis and alleviating the malignant behavior of tumors. In summary, UCP2 is a potential therapeutic target for GBM. Genipin, which targets UCP2, effectively inhibits GBM development by inducing ferroptosis and . These findings indicate that genipin treatment based on UCP2 targeting has potential therapeutic applications with a clinical perspective for the treatment of GBM patients.
RNA modifications: emerging players in the regulation of reproduction and development
Wen J, Zhu Q, Liu Y and Gou LT
The intricate world of RNA modifications, collectively termed the epitranscriptome, covers over 170 identified modifications and impacts RNA metabolism and, consequently, almost all biological processes. In this review, we focus on the regulatory roles and biological functions of a panel of dominant RNA modifications (including m A, m C, Ψ, ac C, m A, and m G) on three RNA types-mRNA, tRNA, and rRNA-in mammalian development, particularly in the context of reproduction as well as embryonic development. We discuss in detail how those modifications, along with their regulatory proteins, affect RNA processing, structure, localization, stability, and translation efficiency. We also highlight the associations among dysfunctions in RNA modification-related proteins, abnormal modification deposition and various diseases, emphasizing the roles of RNA modifications in critical developmental processes such as stem cell self-renewal and cell fate transition. Elucidating the molecular mechanisms by which RNA modifications influence diverse developmental processes holds promise for developing innovative strategies to manage developmental disorders. Finally, we outline several unexplored areas in the field of RNA modification that warrant further investigation.
Mechanism of RSL3-induced ferroptotic cell death in HT22 cells: crucial role of protein disulfide isomerase
Hou MJ, Huang X and Zhu BT
Protein disulfide isomerase (PDI) was recently shown to be an upstream mediator of erastin-induced, glutathione depletion-associated ferroptosis through its catalysis of nitric oxide synthase (NOS) dimerization and nitric oxide (NO) accumulation. A recent study reported that RSL3, a known ferroptosis inducer and glutathione peroxidase 4 (GPX4) inhibitor, can inhibit thioredoxin reductase 1 (TrxR1). The present study seeks to test the hypothesis that RSL3 may, through its inhibition of TrxR1, facilitate PDI activation ( . ., in a catalytically active, oxidized state), thereby enhancing RSL3-induced ferroptosis through NOS dimerization and NO accumulation. Using HT22 mouse neuronal cells as an model, we show that treatment of these cells with RSL3 strongly increases NOS protein levels and that PDI-mediated NOS dimerization is activated by RSL3, resulting in NO accumulation. Mechanistically, we find that PDI is activated in cells treated with RSL3 because of its inhibition of TrxR1, and the activated PDI then catalyzes NOS dimerization, which is followed by the accumulation of cellular NO, ROS and lipid-ROS and ultimately ferroptotic cell death. Genetic or pharmacological inhibition of PDI or TrxR1 partially abrogates RSL3-induced NOS activation and the subsequent accumulation of cellular NO, ROS/lipid-ROS, and ultimately ferroptosis in HT22 cells. The results of this study clearly show that PDI activation resulted from RSL3 inhibition of TrxR1 activity contributes crucially to RSL3-induced ferroptosis in a cell culture model through the PDI→NOS→NO→ROS/lipid-ROS pathway, in addition to its known inhibition of GPX4 activity.
The peripheral Atf3 neuronal population is responsible for nerve regeneration at the early stage of nerve injury revealed by single-cell RNA sequencing
Liu L, Chen J, Yin W, Gao P, Fan Y, Wen D, Jiao Y and Yu W
Peripheral nerve injury (PNI) can transform primary somatosensory neurons to a regenerative state. However, the details of the transcriptomic changes associated with the nerve regeneration of somatosensory neurons remain unclear. In this study, single-cell RNA sequencing (scRNA-seq) is conducted on mouse dorsal root ganglion (DRG) cells after the early stage of nerve injury on day 3 after chronic constriction injury (CCI). We observe that a novel CCI-induced neuronal population (CIP) emerge and express high levels of activating transcription factor ( ), a neuronal injury marker. CIP neurons highly express regeneration-associated genes (RAGs) and are enriched in regeneration-related gene ontology (GO) terms, suggesting that these neurons can constitute a pro-regenerative population. Moreover, intercellular communication networks show that CIP neurons closely communicate with satellite glial cells (SGCs) and specifically transmit strong - signaling to SGCs, which could initiate regeneration-associated transcriptional changes in SGCs. We also confirm that regenerative progress occurs at the early stage of nerve injury because immunohistochemistry shows that the expression of ATF3 is significantly increased beginning at 3 days post-CCI and decreased at 1 month post-CCI. Our bioinformatics analysis at single-cell resolution advances the knowledge of regenerative dynamic transcriptional changes in DRG cells after injury and the underlying molecular mechanisms involved.
SIRPα modulates the podocyte cytoskeleton through influencing the phosphorylation of FAK at tyrosine residue 597
Xia Y, Zhao Y, Tian J, Yang X, Fan Y, Dong S, Yang F, Zhang M and Zeng C
Signal regulatory protein α (SIRPα) is recognized as a significant transmembrane protein within the glomeruli that is specifically localized in podocytes, where it plays a role in modulating downstream signaling pathways through phosphorylation. Upon tyrosine phosphorylation of the immunoreceptor tyrosine-based inhibitory motif (ITIM) within SIRPα, protein tyrosine phosphatases are recruited to facilitate the dephosphorylation of downstream signals. Nevertheless, the specific downstream signaling pathways affected by this mechanism have yet to be elucidated. In this study, phosphoproteomic analysis is conducted on podocytes with SIRPα deficiency to identify proteins whose phosphorylation is regulated by SIRPα and the associated signaling pathways in human podocytes. The results reveal significant alterations in biological processes related to cytoskeleton arrangement and cytoskeleton protein binding. Specifically, an increase in FAK tyrosine phosphorylation at Y576 is identified as a potentially crucial signal of the influence of SIRPα on the podocyte cytoskeleton. Our study suggests that SIRPα may facilitate podocyte cytoskeleton rearrangement and migration through the Src/FAK/p38 MAPK signaling pathway. For the first time, we discover increased level of SIRPα, which is strongly linked to urinary protein, in the urine of patients with nephrotic syndrome (NS). Additionally, an increase in urinary FAK level is observed in NS patients, which is positively correlated with both urinary protein level and urinary SIRPα level. These findings suggest that SIRPα and FAK may serve as promising biomarkers for podocytopathies.
Advances in PIWI-piRNA function in female reproduction in mammals
Lv X, Zhang H and Wu L
PIWI-interacting RNAs (piRNAs), which associate with PIWI clade Argonaute proteins to form piRNA-induced silencing complexes (piRISCs) in germline cells, are responsible for maintaining genomic integrity and reproductive function through transcriptional or post-transcriptional suppression of transposable elements and regulation of protein-coding genes. Recent discoveries of crucial PIWI-piRNA functions in oogenesis and embryogenesis in golden hamsters suggest an indispensable role in female fertility that has been obscured in the predominant mouse model of PIWI-piRNA pathway regulation. In particular, studies of piRNA expression dynamics, functional redundancies, and compositional variations across mammal species have advanced our understanding of piRNA functions in male and, especially, female reproduction. These findings further support the use of hamsters as a more representative model of piRNA biology in mammals. In addition to discussing these new perspectives, the current review also covers emerging directions for piRNA research, its implications for female fertility, and our fundamental understanding of reproductive mechanisms.
A novel mutation in SMARCB1 associated with adult Coffin-Siris syndrome and meningioma
Guo Z, Bai J, Liu Y, Zhang X, Yang W, Wang J, Zhang Y, Xiao H, Hao B and Liao S
encodes a core subunit of the SWI/SNF chromatin remodeling complex, which plays a crucial role in the regulation of gene expression. Germline mutations in the gene have been linked to early childhood Coffin-Siris syndrome type 3 (CSS3), a rare congenital malformation syndrome characterized by severe developmental delay and intellectual disability. In this study, we report a family of two adult CSS3 patients with a novel missense mutation (c.1091A>C, p.Lys364Thr) identified through whole-exome sequencing (WES). Both patients exhibit selective difficulties in verbal learning and experience language delays. Additionally, the development of meningioma is confirmed in one of the patients. Mechanistic studies suggest that this missense mutation may abnormally activate the MAPK signaling pathway, which is implicated in the pathogenesis of tumor progression and neurodevelopmental disorders. This is the first reported case of a germline mutation in the gene associated with both CSS3 and meningioma, thereby expanding the phenotypic spectrum of SMARCB1-related disorders.
Retraction: miR-129-5p suppresses proliferation, migration, and induces apoptosis in pancreatic cancer cells by targeting PBX3
Qiu Z, Wang X, Shi Y and Da M
secretory protein VceA promotes FOXO1 entry into the nucleus to shift host cell metabolism toward glycolysis
Cao S, Han X, Deng X, Guo J, Liu L, Zhang Y, Suleimenov M, Zhao T, Li W, Ding J, Xie S and Zhang H
Increased glycolytic metabolism is a key step in the reproduction of and the induction of brucellosis, however, little is known about how this process is regulated during infection. Forkhead box protein O1 (FOXO1) is a transcription factor that regulates energy metabolism. In this study, we employ the yeast two-hybrid system (Y2H) and immunoprecipitation (Co-IP) to reverse screen for the FOXO1 for the first time and identify interactions between FOXO1 and the secretory protein VceA. Our findings reveal that the secretory protein VceA colocalizes with FOXO1 in the cytoplasm. Additionally, we observe that infection of macrophages with ( ) promotes FOXO1 entry into the nucleus, leading to a significant upregulation of glycolysis level in macrophage. Conversely, in a VceA mutant strain (S2308-ΔVceA), we note a significant reduction in the ability of FOXO1 to enter the nucleus, accompanied by a decrease in glycolysis level. Furthermore, interacts with FOXO1 through the secreted protein VceA, promoting the entry of FOXO1 into the nucleus and thereby altering host metabolic patterns. This study provides insights into the mechanisms by which invades host macrophages and induces unique metabolic changes. These insights may offer a novel rationale for developing metabolic therapeutic strategies for the treatment and prevention of related diseases.
Tanshinone IIA potentiates the therapeutic efficacy of glucocorticoids in lipopolysaccharide-treated HEI-OC1 cells through modulation of the FOXP3/Nrf2 signaling pathway
Li J, Zhu X, Ye S, Dong Q, Hou J, Liu J and She W
Glucocorticoids (GCs) are commonly used to treat sudden sensorineural hearing loss (SSNHL), although some patients are resistant to this therapeutic approach. Clinical studies have demonstrated the efficacy of tanshinone IIA (TA) in combination with GC for managing various human ailments. However, it remains unclear whether TA can mitigate GC resistance in SSNHL. Our aim is to elucidate the role of NRF2-induced transcriptional regulation of HDAC2 in influencing GC resistance and investigate the involvement of TA-related molecular pathways in GC resistance. Here, HEI-OC1 cells are treated with lipopolysaccharide (LPS) to establish an model for SSNHL. The cells are subsequently treated with dexamethasone (DXE) or DXE+TA. RT-qPCR and western blot analysis are used to measure the mRNA and protein levels of Forkhead box P3 (FOXP3), nuclear factor erythroid 2-related factor 2 (NRF2), and histone deacetylase 2 (HDAC2). Cell Counting Kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EdU) assays are carried out to assess cell proliferation. Flow cytometry analysis is performed to evaluate apoptosis. Mechanistic studies involve chromatin immunoprecipitation (ChIP), luciferase reporter, and DNA pull-down assays. Our results show that treatment with TA+DEX significantly increases proliferation and suppresses apoptosis in LPS-treated HEI-treated OC1 cells. TA upregulates HDAC2 expression by activating NRF2-mediated transcription of HDAC2, with the NRF2-HDAC2 binding site located at bases 419-429 (ATGACACTCCA) in the promoter sequence of . Furthermore, TA upregulates FOXP3 expression to activate NRF2 transcription, with the predicted FOXP3-binding site located at bases 864-870 (GCAAACA) in the promoter sequence of . In summary, these findings suggest that TA enhances the therapeutic effects of GC on the proliferation and apoptosis of HEI OC1 cells by increasing FOXP3/Nrf2 expression. These results indicate that TA may be promising for ameliorating GC resistance in patients with SSNHL.
SMG-1 serves as a prognostic indicator for the radiotherapy response in head and neck squamous cell carcinoma xenografts and patients
Wang X, Zou Y, Ding RB, Lyu X, Fu Y, Zhou X, Sun Z and Bao J
Ivermectin inhibits the growth of ESCC by activating the ATF4-mediated endoplasmic reticulum stress-autophagy pathway
Liu H, Chai Z, Gao Y, Wang Y and Lu M
Esophageal squamous cell carcinoma (ESCC) is one of the most common forms of malignancy worldwide. However, there is currently a lack of effective chemotherapeutic drugs for ESCC. Ivermectin is a broad-spectrum antiparasitic drug with notable antitumor activity. However, the cellular and molecular mechanisms by which ivermectin inhibits cancer growth remain unclear. In this study, we elucidate the role of ivermectin in ESCC suppression by activating the endoplasmic reticulum (ER) stress and autophagy pathways. In transcriptome analyses, we find that activating transcription factor 4 (ATF4) and DNA damage inducible transcript 3 (DDIT3) are involved in the activation of ER stress by ivermectin. Moreover, ivermectin treatment suppresses the growth of ESCC xenograft tumors in nude mice. Taken together, our results establish the antitumor molecular role of ivermectin in targeting the ER stress-autophagy pathway and suggest that ivermectin is a potential drug candidate for the treatment of ESCC.
Germacrone ameliorates acute lung injury induced by intestinal ischemia-reperfusion by regulating macrophage M1 polarization and mitochondrial defects
Wang Y, He X, Zhang H and Hu W
Intestinal ischemia-reperfusion (I/R) injury severely affects the lungs. Germacrone (Ger) possesses anti-inflammatory and antioxidant properties. However, it is unclear whether it protects the lungs from I/R injury. In this study, we elucidate the mechanisms by which Ger protects lungs from I/R injury. C57BLKS/J male mice are subjected to I/R injury via complete clamping of the superior mesenteric artery. Ger is administered before intestinal I/R. Mitochondrial morphology is observed via electron microscopy. The histopathology of the lung tissues is monitored via hematoxylin-eosin and immunofluorescence staining. The mitochondrial oxygen consumption rate is measured via an XF96 extracellular flux analyzer. In the I/R mouse model, lung specimens present significant lung damage accompanied by increases in the levels of collagen III, vimentin, and α-SMA in lung tissues. After treatment with Ger, lung impairment and fibrosis in I/R-induced acute lung injury (ALI) model mice are restored, suggesting that Ger improves I/R-ALI. In addition, Ger administration decreases the release of inflammatory factors such as IL-1β, IL-6, and COX2, as well as the expressions of M1 macrophage markers, facilitating cell survival in the I/R-ALI model. Additionally, Ger (EC50: 47.16 μM) ameliorates mitochondrial dysfunction by increasing I/R-ALI-induced apoptosis, increasing the expression of SIRT1, and reducing the levels of HIF1-α, Nrf2, and OGG1 in MLE-12 cells. Ger may affect macrophage polarization and improve subsequent mitochondrial defects through the SIRT1-HIF1α-Nrf2 signaling pathway in MLE-12 cells, which ultimately improves lung function and lung inflammation in the I/R-ALI model.
RHBDF1 promotes PERK expression through the JNK/FoxO3 pathway in breast cancer cells
Ryu S, Long H, Quan X, Kim U, Zhao W, Song Y, Li L and Zhang Z
Human rhomboid family-1 ( ) gene is recognized as an oncogene involved in breast cancer development. Previous studies have indicated that RHBDF1 contributes significantly to endoplasmic reticulum (ER) protein homeostasis by stabilizing the binding immunoglobulin protein (BiP) and promoting the unfolded protein response (UPR). Here, we report a relationship between RHBDF1 and the ER stress sensors PERK, IRE1, and ATF6. We show that RHBDF1 deficiency in breast cancer cells results in decreased levels of PERK, pPERK, and peIF2α. These protein levels can be restored in RHBDF1-deficient breast cancer cells by artificial overexpression of RHBDF1 but not IRE1 or ATF6. Additionally, we show that the transcription factor FoxO3 is essential for the RHBDF1-mediated production of PERK. Subsequent analysis reveals that RHBDF1 activates JNK, which causes FoxO3 to translocate into the cell nucleus. These findings demonstrate that RHBDF1 supports the UPR by upregulating the PERK/peIF2α pathway via the JNK/FoxO3 axis and that the functions of RHBDF1 are essential for preserving the homeostasis of ER proteins.
LINC00365 promotes miR-221-5p to inhibit pyroptosis via Dicer in colorectal cancer
Yang W, Huang X, Lv W, Jin Y and Zhu Y
Pyroptosis, a newly discovered form of programmed cell death, is involved in the occurrence, development and drug resistance of a variety of tumors and has attracted increasing attention in recent years. LINC00365 is a novel lncRNA that has rarely been reported before. We previously reported that LINC00365 expression in colorectal cancer is closely associated with poor patient outcomes. Additionally, LINC00365 was confirmed to be positively correlated with miR-221-5p, and miR-221-5p is negatively correlated with gasdermin-D (GSDMD) in colorectal cancer tissues. Bioinformatics analysis and luciferase reporter gene experiments revealed that GSDMD is the target gene of miR-221-5p. Cell function experiments and nude mouse tumor transplantation assays confirmed that LINC00365 could regulate the expressions of pyroptosis-related proteins such as Caspase-1, Caspase-11, NLRP3 and GSDMD. RNA pulldown and RNA immunoprecipitation experiments further elucidated the mechanism by which LINC00365 regulates miR-221-5p. In the present study, we observe that LINC00365 promotes the expression of miR-221-5p by binding to the Dicer enzyme to inhibit GSDMD and plays an antipyroptotic role. Our findings suggest that LINC00365 may serve as a molecular biomarker for estimating the prognosis of patients with colorectal cancer and as a potential therapeutic target for colorectal cancer.
The effect of norepinephrine on ovarian dysfunction by mediating ferroptosis in mice model
Hong H, Xiao C, Weng L, Wang Q and Lai D
Studies have shown that stress is associated with ovarian dysfunction. Norepinephrine (NE), a classic stress hormone involved in the stress response, is less recognized for its role in ovarian function. In this study, an NE-treated mouse model is induced by intraperitoneal injection of NE for 4 weeks. Compared with normal control mice, NE-treated mice show disturbances in the estrous cycle, decreased levels of anti-Mullerian hormone (AMH) and estradiol (E2), and increased level of follicle-stimulating hormone (FSH). Additionally, the numbers of primordial follicles, primary follicles, secondary follicles, and antral follicles are decreased, whereas the number of atretic follicles is increased in NE-treated mice, indicating NE-induced ovarian dysfunction. RNA sequencing further reveals that genes associated with ferroptosis are significantly enriched in NE-treated ovarian tissues. Concurrently, the levels of reactive oxygen species (ROS), ferrous ions, and malondialdehyde (MDA) are increased, whereas the expression level of glutathione peroxidase 4 (GPX4) is decreased. To elucidate the mechanism of NE-induced ferroptosis in ovaries and the potential reversal by Coenzyme Q10 (CoQ10), an antioxidant, we conduct both and experiments. , the granulosa cell line KGN, when treated with NE, shows decreased cell viability, reduced expression of GPX4, elevated levels of ferrous ion and ROS, and increased MDA level. However, these NE-induced changes are reversed by the addition of CoQ10. Compared with the NE group, the NE-treated mice supplemented with CoQ10 present increased GPX4 level and decreased iron, ROS, and MDA levels. Moreover, the differential expression of genes associated with ferroptosis induced by NE is ameliorated by CoQ10 in NE-treated mice. Additionally, CoQ10 improves ovarian function, as evidenced by increased ovarian weight, more regular estrous cycles, and an increase in follicles at various stages of growth in NE-treated mice. In conclusion, NE induces ovarian dysfunction by triggering ferroptosis in ovarian tissues, and CoQ10 represents a promising approach for protecting reproductive function by inhibiting ferroptosis.
Tim-1-mediated extracellular matrix promotes the development of hepatocellular carcinoma
Hua R, Yu P, Zheng W, Wu N, Yu W, Kong Q, He J and Qin L
Tim-1 (T-cell immunoglobulin and mucin domain 1), also known as Kim-1 (kidney injury molecule 1) or hepatitis A virus cellular receptor 1 (HAVCR1), is a transmembrane protein expressed on various immune and epithelial cells. It plays a role in modulating inflammatory and immune responses. In this study, we find that Tim-1 is overexpressed in hepatocellular carcinoma (HCC) samples and that its expression is significantly correlated with postoperative survival. Bulk RNA sequencing reveals a general upregulation of extracellular matrix-related genes in HCC tissues with Tim-1 overexpression. The results of the cell and experiments reveal that Tim-1 in HCC not only affects biological processes such as the proliferation, migration, and invasion of HCC cells but also broadly promotes extracellular matrix processes by influencing cytokine secretion. Further studies demonstrate that Tim-1 mediates the activation of hepatic stellate cells and upregulates Th1 and Th2 cytokines, thereby promoting HCC progression. Thus, Tim-1 may represent a novel target for future interventions in HCC and liver fibrosis.
Battling pain from osteoarthritis: causing novel cell death
Zhang Y, Tao H, Zhang L, Li X, Shi Y, Sun W, Chen W, Zhao Y, Wang L, Yang X and Gu C
Osteoarthritis (OA) is a significant contributor to pain and disability worldwide. Pain is the main complaint of OA patients attending the clinic and has a large impact on their quality of life and economic standards. However, existing treatments for OA-related pain have not been shown to achieve good relief. The main focus is on preventing and slowing the progression of OA so that the problem of OA pain can be resolved. Pain caused by OA is complex, with the nature, location, duration, and intensity of pain changing as the disease progresses. Previous research has highlighted the role of various forms of cell death, such as apoptosis and necrosis, in the progression of pain in OA. Emerging studies have identified additional forms of novel cell death, such as pyroptosis, ferroptosis, and necroptosis that are linked to pain in OA. Different types of cell death contribute to tissue damage in OA by impacting inflammatory responses, reactive oxygen species (ROS) production, and calcium ion levels, ultimately leading to the development of pain. Evidence suggests that targeting novel types of cell death could help alleviate pain in OA patients. This review delves into the complex mechanisms of OA pain, explores the relationship between different modes of novel cell death and pain, and proposes novel cell death as a viable strategy for the treatment of these conditions, with the goal of providing scientific references for the development of future OA pain treatments and drugs.
Diacylglycerol kinase γ facilitates the proliferation and migration of neural stem cells in the developing neural tube
Cui H, Du J, Xie J, Zhang J, Tao Y, Huang Y, Li L, Cao X and Zhang Y
In this study, we aim to investigate diacylglycerol kinase (DGK) γ expression in developing neural tubes (NTs) and its effects on neural stem cell (NSC) proliferation and migration. Whole-mount hybridization (WMISH) and immunohistochemistry are performed to explore DGKγ localization in developing NTs . NSCs are treated with sh-DGKγ, R59949, or PMA . Cell counting kit-8 (CCK-8) assay, 5-ethynyl-2'-deoxyuridine (EdU) assay and neurosphere formation assay are utilized to evaluate NSC proliferation. Neurosphere migration assay and a transwell chamber assay are used to assess NSC migration. The diacylglycerol (DAG) content is detected via enzyme-linked immunosorbent assay (ELISA). The mRNA expression of DGKγ is detected via quantitative real-time polymerase chain reaction (qRT-PCR). The protein expression levels of DGKγ, protein kinase C (PKC) and phosphorylated PKC (p-PKC) are detected via western blot analysis. The results show that DGKγ mRNA is expressed predominantly in developing NTs. The neuroepithelium in developing NTs is positive for NSC markers, including Nestin, glial fibrillary acidic protein (GFAP), and DGKγ. DGKγ is expressed in the cytoplasm and nucleus of the neuroepithelium and is coexpressed with p-PKCγ and p-PKCδ. The proliferation of NSCs, the number of EdU-positive NSCs, and the number of neurospheres are decreased by sh-DGKγ and R59949 but increased by PMA. There is a shorter migration distance of NSCs and fewer migrated NSCs in the sh-DGKγ, R59949 and PMA groups. DAG content and the p-PKCδ/PKCδ ratio are increased by sh-DGKγ, R59949 and PMA, whereas the p-PKCγ/PKCγ ratio is decreased by PMA. Taken together, our findings indicate that DGKγ facilitates NSC proliferation and migration, which is responsible for the participation of DGK in NT development. DGKγ facilitates NSC migration via the DAG/PKCδ pathway.
CircMALAT1 promotes the proliferation and metastasis of intrahepatic cholangiocarcinoma via the miR-512-5p/VCAM1 axis
Zhang M, He M, Bai L, Du F, Xie Y, Li B and Zhang Y
Circular RNAs play a pivotal role in the progression of various cancers. In our previous study, we observed high expression of the circRNA MALAT1 (cMALAT1) in intrahepatic cholangiocarcinoma (ICC) cells co-incubated with activated hepatic stellate cells. This study is designed to explore the roles of cMALAT1 and the underlying mechanisms in ICC. We find that cMALAT1 significantly facilitates the progression of ICC both and . The binding between cMALAT1 and miR-512-5p is subsequently confirmed through RNA pull-down experiments. As anticipated, the application of miR-512-5p mimics noticeably reverses the cMALAT1 overexpression-induced malignant phenotypes of ICC cells. Furthermore, is identified as a downstream gene of the cMALAT1/miR-512-5p axis. Importantly, silencing of not only effectively suppresses the malignant phenotypes of ICC cells but also significantly impairs the functions of cMALAT1. Our study reveals that cMALAT1 promotes the progression of ICC by competitively binding to mRNA with miR-512-5p, leading to the upregulation of VCAM1 expression and the activation of the PI3K/AKT signaling pathway.
L. flower-derived anthocyanins and flavonoids inhibit bladder cancer growth by suppressing SREBP1 pathway-mediated fatty acid synthesis
Liu C, Liu J, Liu G, Song Y, Yang X, Gao H, Xiang C, Sang J, Xu T and Sang J
L. flowers are used as traditional herbal medicines and are known for their advanced pharmacological activities. Flavonoids and anthocyanins reportedly contribute to the therapeutic properties of . flowers; however, their potential anti-bladder cancer effects and molecular mechanisms remain unknown. In this study, flavonoid- and anthocyanin-rich samples from . flowers (DDH) are prepared via macroporous resin-based extraction coupled with an efficient and reliable two-dimensional UPLC-DAD-MS/MS method. and studies reveal that DDH can inhibit bladder cancer cell growth and enhance the anti-bladder cancer activity of cisplatin. RNA-seq combined with KEGG analysis reveals that fatty acid synthesis is closely related to the anti-bladder cancer effect of DDH. Furthermore, DDH dose-dependently reduces cellular fatty acid levels in bladder cancer cells, and the addition of fatty acids significantly mitigates DDH-induced cell growth inhibition. Subsequent findings reveal that DDH downregulates sterol regulatory element-binding protein 1 (SREBP1), a key transcriptional regulator of fatty acid synthesis in cancer cells, and its downstream targets (FASN, SCD1, and ACC). Additionally, this study demonstrates that gallic acid not only enhances the stability of DDH but also synergistically potentiates its anti-bladder cancer activity. Our study suggests that targeting the SREBP1 pathway is an effective strategy in bladder cancer therapy, and the ability of DDH to induce cell death by inhibiting the SREBP1 pathway and its good tolerance in mice make it a promising strategy for preventing and treating bladder cancer.