Cyclin B1/Cdk1 coordinates mitochondrial respiration for cell-cycle G2/M progression

Isorhamnetin exerts anti-proliferative effect on cancer-associated fibroblasts by inducing cell cycle arrest

Isorhamnetin (ISO), a dietary flavonoid, has been shown to possess antioxidant, anti-cancer, and anti-inflammatory properties. Cancer-associated fibroblasts (CAFs), found in the tumor microenvironment of several types of cancer including pancreatic ductal adenocarcinoma (PDAC) impact the tumor growth and development of chemoresistance. Thus, modulating CAFs is an attractive mean to increase the efficacy of therapies targeting cancer cells. In this study, the anti-proliferative effect of ISO and the underlying transcriptomic profile of ISO-treated PDAC-derived CAFs were investigated. ISO treatment showed a time- and concentration-dependent decrease in cell viability with a slight increase in apoptotic cells. Microarray and cell cycle analyses revealed ISO induced downregulation of pathways in cell cycle and DNA replication; and G2/M checkpoint. Cell cycle analysis showed cells in the G2/M phase were increased. In response to the treatment, hallmark for p53 pathway genes, known to regulate cell cycle checkpoints, were highly upregulated. Moreover, ISO-treated cells had an increased area of the mitochondrial network, but lower mitochondrial membrane potential accompanied by a decrease of ATP production, measured by oxygen consumption rate. Inflammatory gene expression of IL1A1, IL6, CXCL1, and LIF were significantly inhibited in ISO-treated CAFs. Taken together, our results demonstrated that the cytostatic effect of ISO on human CAFs was mediated by inducing cell cycle arrest at G2/M phase associated with activation of p21, impaired mitochondrial homeostasis, and inhibition of inflammatory mediators gene expression, warranting further investigation for its use in combinatorial therapy that target both the cancer and the tumor microenvironment as a whole.

Costunolide inhibits the progression of TPA-induced cell transformation and DMBA/TPA-induced skin carcinogenesis by regulation of AKT-mediated signaling

BACKGROUND

Costunolide (COS), a sesquiterpene lactone extracted from the roots of Saussurea costus, is known to possess anticancer properties in various cancers, including colon, oral, and lung cancers, but its mechanism of action in skin carcinogenesis has not yet been explored. Present study investigates the chemopreventive mechanism of COS on skin inflammation and carcinogenesis both in vitro and in vivo.

METHODS

The cytotoxicity of COS was examined on a normal murine epidermal cell line, JB6, by treating with COS using the WST-8 assay. Subsequently, the effect of COS on 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cellular transformation was assessed through a soft-agar assay. Furtherly, cell cycle and apoptosis analysis and the expression of related proteins were determined via flow cytometry and Western blotting, respectively. The effects of COS on tumor promotion induced by DMBA/TPA treatment and the underlying molecular mechanisms in mouse skin carcinogenesis were identified through H&E staining and immunohistochemical analysis.

RESULTS

COS significantly inhibited colony growth and number in TPA-induced JB6 cells transformation, arrested the cell cycle at the G2/M phase, increased p21 expression, and decreased cyclin B expression. In addition, COS induced cell apoptosis and increased the related markers expression including cleaved caspase-3 and - 7. COS suppressed the expression of phosphorylated AKT and its downstream signaling proteins and effectively reduced the translocation of phosphorylated NF-κB from the cytosol to the nucleus. Moreover, COS reduced papilloma formation in mouse skin and inhibited hyperplasia and phosphorylated AKT expression in tissues.

CONCLUSION

These results demonstrate that COS inhibits TPA-induced cellular transformation and skin carcinogenesis both in vitro and in vivo through the AKT signaling pathway. Our findings suggest the potential of COS as a chemopreventive agent for skin carcinogenesis, highlighting its significance for further investigation in cancer prevention and therapy.

Integrated transcriptomic and metabolomic analysis reveals the effects of EMMPRIN on nucleotide metabolism and 1C metabolism in AS mouse BMDMs

Background

Extracellular matrix metalloproteinase inducer (EMMPRIN) has been considered as a key promoting factor in atherosclerosis (AS). Some studies have shown that regulating EMMPRIN expression in bone marrow-derived macrophages (BMDMs) of ApoE-/- mice can affect plaque stability, but the mechanism was not clear.

Methods

AS model mice were built from high-fat-feeding ApoE -/- mice, and were divided into siE group and CON group. The BMDMs and aortas from AS mice were harvested following in vivo treatment with either EMMPRIN short interfering (si)RNA (siEMMPRIN) or negative control siRNA. Transcriptomic and metabolomic profiles were analyzed using RNA-sequencing and Liquid chromatography-tandem mass spectrometry (LC-MS/MS), respectively. The efficacy of siEMMPRIN was assessed through real-time quantitative polymerase chain reaction (RT-qPCR) and Western blotting (WB). Immunofluorescence staining was employed to measure EMMPRIN expression within aortic atherosclerotic plaques. Cell proliferation was monitored using the Cell Counting Kit-8 (CCK8), while flow cytometry was utilized to analyze the cell cycle. Additionally, seahorse analysis and oil red O staining were conducted to verify glucose and lipid metabolism, respectively.

Results

A total of 3,282 differentially expressed metabolites (DEMs) and 16,138 differentially expressed genes (DEGs) were identified between the CON group and siE group. The nucleotide metabolism and one-carbon (1C) metabolism were identified as major altered pathways at both the transcriptional and metabolic levels. Metabolomic results identified increased levels of glycine, serine, betaine and S-adenosyl-L-methionine (SAM) to S-adenosyl-L-homocysteine (SAH) ratio and decreased levels of dimethylglycine (DMG) and SAH in 1C metabolism, accompanied by the accumulation of nucleotides, nucleosides, and bases in nucleotide metabolism. Transcriptomics results shown that Dnmt, Mthfd2 and Dhfr were downregulated, while Mthfr were upregulated in 1C metabolism. And numerous genes involved in de novo nucleotide synthesis, pentose phosphate pathway (PPP) and dNTP production were significantly inhibited, which may be associated with decreased BMDMs proliferation and cell cycle arrest in the G0/G1 phase in siE group. Multi-omics results also showed changes in glucose and lipid metabolism. Seahorse assay confirmed reduced glycolysis and oxidative phosphorylation (OXPHOS) levels and the Oil Red O staining confirmed the decrease of lipid droplets in siE group.

Conclusion

The integrated metabolomic and transcriptomic analysis suggested that nucleotide metabolism and 1C metabolism may be major metabolic pathways affected by siEMMPRIN in AS mouse BMDMs. Our study contributes to a better understanding of the role of EMMPRIN in AS development.

A novel amino-pyrimidine inhibitor suppresses tumor growth via microtubule destabilization and Bmi-1 down-regulation

Colorectal cancer (CRC), one of the diseases posing a threat to global health, according to the latest data, is the third most common cancer globally and the second leading cause of cancer-related deaths. The development and refinement of novel structures of small molecular compounds play a crucial role in tumor treatment and overcoming drug resistance. In this study, our objective was to screen and characterize novel compounds for overcoming drug resistance via the B Lymphoma Mo-MLV insertion region 1 (Bmi-1) reporter screen assay. The stable cell line harboring the Bmi-1 reporter gene was utilized to screen 300 compounds, leading to the identification of an amino-pyrimidine compound, APD-94. In vitro, APD-94 markedly inhibited cancer cell proliferation and decreased Bmi-1 expression at both the RNA and protein levels. In vivo, APD-94 repressed the growth of HT29 cell xenografts in NOD/SCID mice without notable side effects. Flow cytometry results demonstrated that APD-94 induced G2/M phase arrest and apoptosis in cells. APD-94 was identified as a novel inhibitor of microtubule polymerization by directly targeting the tubulin. Furthermore, APD-94 was more effective in overcoming the resistance to paclitaxel in paclitaxel-resistant A549/Tax cells. This bifunctional inhibitor is a promising candidate drug for CRC treatment.

3-Hydroxyanthranic acid inhibits growth of oral squamous carcinoma cells through growth arrest and DNA damage inducible alpha

OBJECTIVES

The specific role of 3-hydroxyanthranilic acid(3-HAA) in oral squamous cell carcinoma (OSCC) remains unclear. This study investigated the roles of 3-HAA in OSCC and the underlying mechanism.

MATERIALS AND METHODS

The effects of 3-HAA on OSCC were examined using CCK-8, colony formation, EdU incorporation assays and xenograft mouse model. The underlying mechanisms were investigated with RNA-seq, apoptosis array and cell cycle array. Short hairpin RNAs (shRNAs) were used to knockdown the expression of growth arrest and DNA damage inducible alpha (GADD45A) in OSCC cells. CCK-8 and xenograft mouse model were employed to elucidate the role of GADD45A. The binding sites between GADD45A and Yin Yang 1(YY1) were determined using luciferase reporter assay.

RESULTS

3-HAA was selectively down-regulated in OSCC patients and the decreasing level intensified with pathological progression. Higher expression of kynurenine 3-monooxygenase (KMO) and kynureninase (KYNU), which can increase the content of 3-HAA, was associated with poorer prognosis of OSCC patients. Exogenous 3-HAA hampered growth of OSCC cells both in vitro and in vivo. 3-HAA induced growth arrest, G2/M-phase arrest, and apoptosis of OSCC cells. RNA-seq indicated that 3-HAA significantly increased GADD45A expression. 3-HAA promoted transcription of GADD45A by transcription factor YY1. Knockdown of GADD45A significantly reversed 3-HAA-induced growth inhibition of OSCC cells in vivo and in vitro.

DISCUSSION

3-HAA induced apoptosis and cell cycle arrest of OSCC cells via GADD45A, indicating that 3-HAA and GADD45A are potential therapeutic targets for OSCC.

AdipoR1 enhances the radiation resistance via ESR1/CCNB1IP1/cyclin B1 pathway in hepatocellular carcinoma cells

Hepatocellular carcinoma is one of the most common malignant tumors, and radiotherapy plays a pivotal role in its therapeutic regimen. However, radiotherapy resistance is the main cause of therapeutic failure in patients. Our previous study revealed that Adiponectin Receptor 1 (AdipoR1) is involved in regulating radiation resistance in liver cancer patients treated with stereotactic body radiotherapy. To explore the mechanism, we performed high-throughput transcriptome sequencing of hepatocellular carcinoma cells with stable knockdown of AdipoR1. KEGG enrichment analysis indicated that the cell cycle and ubiquitination degradation pathways may be involved in the regulation of radiation resistance by AdipoR1.The knockdown of AdipoR1 can attenuate the radiation-induced G2/M phase arrest through cyclin B1.By the ubiquitination IP assay and a rescue experiment, we confirmed that CCNB1IP1 regulated the ubiquitination and degradation of cyclin B1. Combined with information from transcription factor database and AdipoR1 transcriptome sequencing, these results showed that estrogen receptor 1 (ESR1) may be a transcription factor of CCNB1IP1. We found that AdipoR1 promoted the translocation of ESR1 from the cytoplasm to the nucleus, and ESR1 inhibited the transcription of CCNB1IP1.Therefore, we propose that AdipoR1 regulates the ubiquitination level, cell cycle progression, and radiation resistance of HCC cells through the "AdipoR1 /ESR1/CCNB1IP1/cyclin B1" axis. This study will promote the development of novel targeted radiosensitizing drugs.

The role of cell cycle-related genes in the tumorigenesis of adrenal and thyroid neuroendocrine tumors

The molecular mechanisms underlying adrenal and thyroid neuroendocrine tumors, including their tumorigenesis, progression, and metastasis, involve unique pathways regulating cell cycle progression. To better understand these mechanisms and pathways, extensive in-depth research on cell cycle-related genes is necessary. This review aims to describe and interpret current single-cell RNA sequencing studies on neuroblastoma, medullary thyroid cancer, and pheochromocytoma tumors. Our review summarizes differentially expressed cell cycle-related genes with distinct functions, highlighting their potential as therapeutic targets and components of panels used to determine tumor type or aggressiveness. Although some insights have been gained, there is still limited information on these topics, and further research is required to explore the regulatory mechanisms of these tumors.

The PST repeat region of MDC1 is a tunable multivalent chromatin tethering domain

DNA double strand breaks (DSBs) are widely considered the most cytotoxic DNA lesions occurring in cells because they physically disrupt the connectivity of the DNA double helix. Homologous recombination (HR) is a high-fidelity DSB repair pathway that copies the sequence spanning the DNA break from a homologous template, most commonly the sister chromatid. How both DNA ends, and the sister chromatid are held in close proximity during HR is unknown. Here we demonstrate that the PST repeat region of MDC1 is a mutlivalent nucleosome binding domain, sufficient to tether chromatin in multiple contexts. In mitotic cells the affinity of the PST repeats for chromatin is downregulated by phosphorylation to prevent chromosome missegregation, while still contributing to DNA break tethering by the MDC1-TOPBP1-CIP2A complex. In interphase, the PST repeat region is critical for RAD51 focus formation but not the recruitment of 53BP1 to DNA breaks, consistent with a chromatin tethering function. In total, this work demonstrates that the PST repeat region of MDC1 is a multivalent chromatin binding domain with tunable affinity that contributes to DNA break tethering during HR and in mitosis.

Identification and validation of CDK1 as a promising therapeutic target for Eriocitrin in colorectal cancer: a combined bioinformatics and experimental approach

BACKGROUND

Colorectal cancer (CRC) is a prevalent malignancy worldwide, associated with significant morbidity and mortality. Cyclin-dependent kinase 1 (CDK1) plays a crucial role in cell cycle regulation and has been implicated in various cancers. This study aimed to evaluate the prognostic value of CDK1 in CRC and to identify traditional Chinese medicines (TCM) that can target CDK1 as potential treatments for CRC.

METHODS

The expression and prognostic value of CDK1 were analyzed through TCGA, GEO, GEPIA, UALCAN and HPA databases. An ESTIMATE analysis was applied to estimate the proportions of stromal and immune cells in tumor samples. GO and KEGG enrichment analyses were performed to clarify the functional roles of CDK1-related genes. CCK-8, colony formation, cell migration, cell invasion, and wound healing assays were employed to explore tumor-promoting role of CDK1. Molecular docking, cellular thermal shift, and isothermal dose-response assays were employed to identify potential inhibitors of CDK1.

RESULTS

CDK1 was highly expressed in CRC and associated with a poorer prognosis. The expression of CDK1 was also correlated with the levels of immune cells infiltration. CDK1-related genes were primarily involved in the cell cycle and the P53 signaling pathway. Knockdown of CDK1 inhibited the proliferation, migration, and invasion of CRC cells in vitro. Furthermore, Eriocitrin emerged as a potential inhibitor, exerting its anti-tumor effects by targeting and inhibiting CDK1 activity.

CONCLUSION

CDK1 plays a critical role in CRC prognosis. Eriocitrin, a potential CDK1 inhibitor derived from TCM, highlights a promising new therapeutic strategy for CRC treatment.

Cyclin-dependent protein kinases and cell cycle regulation in biology and disease

Cyclin Dependent Kinases (CDKs) are closely connected to the regulation of cell cycle progression, having been first identified as the kinases able to drive cell division. In reality, the human genome contains 20 different CDKs, which can be divided in at least three different sub-family with different functions, mechanisms of regulation, expression patterns and subcellular localization. Most of these kinases play fundamental roles the normal physiology of eucaryotic cells; therefore, their deregulation is associated with the onset and/or progression of multiple human disease including but not limited to neoplastic and neurodegenerative conditions. Here, we describe the functions of CDKs, categorized into the three main functional groups in which they are classified, highlighting the most relevant pathways that drive their expression and functions. We then discuss the potential roles and deregulation of CDKs in human pathologies, with a particular focus on cancer, the human disease in which CDKs have been most extensively studied and explored as therapeutic targets. Finally, we discuss how CDKs inhibitors have become standard therapies in selected human cancers and propose novel ways of investigation to export their targeting from cancer to other relevant chronic diseases. We hope that the effort we made in collecting all available information on both the prominent and lesser-known CDK family members will help in identify and develop novel areas of research to improve the lives of patients affected by debilitating chronic diseases.

The Cyclin-Dependent Kinase activity modulates the central carbon metabolism in maize during germination

The cell cycle is predominantly controlled by Cyclins/Cyclin-Dependent Kinases (Cyc/CDK) complexes, which phosphorylate targets involved in cellular proliferation. Evidence suggests that Cyc/CDK targets extend beyond traditional proteins and include enzymes that regulate the central carbon metabolism. Maize embryo axes rapidly internalize and metabolize glucose. After 24 h of imbibition in glucose-rich media, axes exhibited increased length and weight, with more pronounced effects at 72 h. This morphology enhancement was impaired when RO-3306, a specific CDK inhibitor, was added. The protein profile of maize embryo extracts at 18 and 24 h indicated altered phosphorylation patterns following CDK activity inhibition. Metabolomic analysis at 24 h of imbibition revealed that maize embryos without sugar in the media, with or without RO-3306, had a decreased sugar and amino acid content. Conversely, axes exposed to glucose demonstrated increased conversion into various mono and di-saccharides such as fructose, mannitol, galactose, and maltose but not sucrose. This pattern was reversed upon the addition of RO-3306. Glucose promoted the accumulation of amino acids such as cysteine, valine, leucine, and intermediates of the tricarboxylic acid (TCA) cycle, such as malate and citrate. The CDK inhibitor redirected the glucose metabolism toward increased serine levels, followed by other amino acids like phenylalanine, valine, and leucine. Additionally, TCA cycle intermediates and sterols significantly decreased. Overall, these results contribute to understanding the role of CDK in maize morphogenesis during germination and underscore its impact on modulating various central carbon pathways, including glycolysis, amino acid catabolism/anabolism, TCA cycle, and sterols biosynthesis.

Remodeling of ER Membrane Contact Sites During Cell Division

Membrane contact sites (MCS) provide specialized conduits for inter-organelle communications to maintain cellular homeostasis. Most organelles are interconnected, which supports their coordination and function. M-phase (mitosis or meiosis) is associated with dramatic cellular remodeling to support cell division, including the equal distribution of organelles to the two daughter cells. However, the fate of MCS in M-phase is poorly understood. Here we review recent advances arguing for differential remodeling of endoplasmic reticulum (ER) MCS with the plasma membrane (PM, ERPMCS) and the mitochondria (MERCS) during cell division.

Proapoptotic role of CDK1 in overcoming paclitaxel resistance in ovarian cancer cells in response to combined treatment with paclitaxel and duloxetine

BACKGROUND

Paclitaxel resistance and recurrence are major obstacles in ovarian cancer, which is the leading cause of death among gynecologic cancers. During cancer cell progression, cyclin-dependent kinase 1 (CDK1) drives cells through the G2 phase and into mitosis. In this study, we demonstrated that CDK1 played a crucial role in switching paclitaxel-resistant ovarian cancer cells from mitotic arrest to apoptosis following combined treatment with paclitaxel and duloxetine, an antidepressant known as a serotonin-norepinephrine reuptake inhibitor (SNRI).

METHODS

Cell viability was assessed by MTT assay. Apoptotic cell death and mitochondrial membrane potential (MMP) were detected by flow cytometry. Protein expression levels were explored using western blotting. Mitochondrial and cytosolic fractionation were performed to determine the mitochondrial localization of proteins. Immunofluorescence was used to detect protein expression levels and localization.

RESULTS

Combined treatment with paclitaxel and duloxetine induced apoptotic cell death in paclitaxel-resistant ovarian cancer cells. We suggested that combined treatment of these drugs induced CDK1 activation and increased mitochondrial localization of activated CDK1, which caused phosphorylation of the antiapoptotic Bcl-2 and Bcl-xL proteins. Selective CDK1 inhibitors blocked Bcl-2 and Bcl-xL phosphorylation induced by paclitaxel and duloxetine, and strongly suppressed apoptotic cell death. Furthermore, we demonstrated that S6K is a potential upstream mediator of the proapoptotic activation of CDK1.

CONCLUSION

Taken together, switching CDK1 to a proapoptotic role through the combination of paclitaxel and duloxetine could overcome paclitaxel resistance in ovarian cancer cells, providing promising therapeutic strategies for treating paclitaxel-resistant ovarian cancer.

The Dose Rate of Corpuscular Ionizing Radiation Strongly Influences the Severity of DNA Damage, Cell Cycle Progression and Cellular Senescence in Human Epidermoid Carcinoma Cells

Modern radiotherapy utilizes a broad range of sources of ionizing radiation, both low-dose-rate (LDR) and high-dose-rate (HDR). However, the mechanisms underlying specific dose-rate effects remain unclear, especially for corpuscular radiation. To address this issue, we have irradiated human epidermoid carcinoma A431 cells under LDR and HDR regimes. Reducing the dose rate has lower lethality at equal doses with HDR irradiation. The half-lethal dose after HDR irradiation was three times less than after LDR irradiation. The study of mechanisms showed that under HDR irradiation, the radiation-induced halt of mitosis with the accompanying emergence of giant cells was recorded. No such changes were recorded after LDR irradiation. The level of DNA damage is significantly greater after HDR irradiation, which may be the main reason for the different mechanisms of action of HDR and LDR irradiations. Comparing the mechanisms of cell response to LDR and HDR irradiations may shed light on the mechanisms of tumor cell response to ionizing radiation and answer the question of whether different dose rates within the same dose range can cause different clinical effects.

Identification of hub genes affecting gestational diabetes mellitus based on GEO database

This research aimed to obtain gestational diabetes mellitus (GDM) related hub genes, providing new targets for clinical diagnosis and treatment of GDM. The microarray data of GSE9984 and GSE103552 were obtained from the Gene Expression Omnibus (GEO). The dataset GSE9984 contained placental gene expression profiles of 8 GDM patients and four healthy specimens. The dataset GSE103552 contained 20 specimens from GDM patients and 17 normal specimens. The differentially expressed genes (DEGs) were identified by GEO2R online analysis. DAVID database was applied to conduct functional enrichment analysis of the DEGs. The Search Tool for the Retrieval of Interacting Genes (STRING) database was adopted to acquire protein-protein interaction (PPI) networks. A total of 195 up-regulated and 371 down-regulated DEGs were selected in the GSE9984, and total of 191 up-regulated and 229 down-regulated DEGs were selected in the GSE103552. In the two datasets, 24 common differential genes were obtained and named co-DEGs. The Gene Ontology (GO) annotation analysis indicated the DEGs participated in multi-multicellular organism process, endocrine hormone secretion, long-chain fatty acid biosynthetic process, cell division, unsaturated fatty acid biosynthetic process, cell adhesion and cell recognition. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis suggested that GSE9984 and GSE103552 were related to vitamin digestion and absorption, tryptophan metabolism, steroid hormone biosynthesis, Ras signaling pathway, protein digestion and absorption, PPAR signaling pathway, PI3K-Akt signaling pathway, p53 signaling pathway. PPI was constructed in string database, and six hub genes were selected, including CCNB1, APOA2, AHSG and IGFBP1. Four critical genes were identified to be considered as therapeutic potential biomarkers of GDM, including CCNB1, APOA2, AHSG and IGFBP1.

Dual inhibition of topoisomerase II and microtubule of podophyllotoxin derivative 5p overcomes cancer multidrug resistance

Compound 5p is a 4β-N-substituted podophyllotoxin derivative, which exhibited potent activity toward drug-resistant K562/A02 cells and decreased MDR-1 mRNA expression. Here, we further investigated its detail mechanism and tested its antitumor activity. 5p exerted catalytic inhibition of topoisomerase IIα, and didn't show the inhibitor of topoisomerase I. 5p exhibited the inhibitory effect on microtubule polymerization. 5p showed potent anti-proliferation against breast cancer, oral squamous carcinoma, and their drug-resistant cell lines, with resistance index of 0.61 and 0.86, respectively. 5p downregulated the expression levels of P-gp in KBV200 cells and BCRP in MCF7/ADR cells in dose-dependent manner. Moreover, 5p induced KB and KBV200 cells arrest at G2/M phase by up-regulating the expression of γ-H2AX, p-Histone H3 and cyclin B1. 5p induced apoptosis and pyroptosis by increased the expression levels of cleaved-PARP, cleaved-caspase3, N-GSDME as well as LDH release in KB and KBV200 cells. In addition, 5p efficiently impaired tumor growth in KB and KBV200 xenograft mice. Conclusively, this work elucidated the dual inhibitor of topoisomerase II and microtubule of 5p and its mechanism of overcoming the multidrug resistance, indicating that 5p exerts the antitumor potentiality.

NL13, a novel curcumin analogue and polo like kinase 4 inhibitor, induces cell cycle arrest and apoptosis in prostate cancer models

BACKGROUND AND PURPOSE

Prostate cancer remains a major public health burden worldwide. Polo like kinase 4 (PLK4) has emerged as a promising therapeutic target in prostate cancer due to its key roles in cell cycle regulation and tumour progression. This study aims to develop and characterize the novel curcumin analogue NL13 as a potential therapeutic agent and PLK4 inhibitor against prostate cancer.

EXPERIMENTAL APPROACH

NL13 was synthesized and its effects were evaluated in prostate cancer cells and mouse xenograft models. Kinome screening and molecular modelling identified PLK4 as the primary target. Antiproliferative and proapoptotic mechanisms were explored via cell cycle, apoptosis, gene and protein analyses.

KEY RESULTS

Compared with curcumin, NL13 exhibited much greater potency in inhibiting PC3 (IC50, 3.51 μM vs. 35.45 μM) and DU145 (IC50, 2.53 μM vs. 29.35 μM) prostate cancer cells viability and PLK4 kinase activity (2.32 μM vs. 246.88 μM). NL13 induced G2/M cell cycle arrest through CCNB1/CDK1 down-regulation and triggered apoptosis via caspase-9/caspase-3 cleavage. These effects were mediated by PLK4 inhibition, which led to the inactivation of the AKT signalling pathway. In mice, NL13 significantly inhibited tumour growth and modulated molecular markers consistent with in vitro findings, including decreased p-AKT and increased cleaved caspase-9/3.

CONCLUSION AND IMPLICATIONS

NL13, a novel PLK4-targeted curcumin analogue, exerts promising anticancer properties against prostate cancer by disrupting the PLK4-AKT-CCNB1/CDK1 and apoptosis pathways. NL13 represents a promising new agent for prostate cancer therapy.

Mitotic ER-mitochondria contact enhances mitochondrial Ca2+ influx to promote cell division

Cell division is tightly regulated and requires an expanded energy supply. However, how this energy is generated remains unclear. Here, we establish a correlation between two mitochondrial Ca2+ influx events and ATP production during mitosis. While both events promote ATP production during mitosis, the second event, the Ca2+ influx surge, is substantial. To facilitate this Ca2+ influx surge, the lamin B receptor (LBR) organizes a mitosis-specific endoplasmic reticulum (ER)-mitochondrial contact site (ERMCS), creating a rapid Ca2+ transport pathway. LBR acts as a tether, connecting the ER Ca2+ release channel IP3R with the mitochondrial VDAC2. Depletion of LBR disrupts the Ca2+ influx surge, reduces ATP production, and postpones the metaphase-anaphase transition and subsequent cell division. These findings provide insight into the mechanisms underlying mitotic energy production and supply required for cell proliferation.

The Changes of Mitochondria during Aging and Regeneration

Aging and regeneration are opposite cellular processes. Aging refers to progressive dysfunction in most cells and tissues, and regeneration refers to the replacement of damaged or dysfunctional cells or tissues with existing adult or somatic stem cells. Various studies have shown that aging is accompanied by decreased regenerative abilities, indicating a link between them. The performance of any cellular process needs to be supported by the energy that is majorly produced by mitochondria. Thus, mitochondria may be a link between aging and regeneration. It should be interesting to discuss how mitochondria behave during aging and regeneration. The changes of mitochondria in aging and regeneration discussed in this review can provide a timely and necessary study of the causal roles of mitochondrial homeostasis in longevity and health.

Telomere Reprogramming and Cellular Metabolism: Is There a Link?

Telomeres-special DNA-protein structures at the ends of linear eukaryotic chromosomes-define the proliferation potential of cells. Extremely short telomeres promote a DNA damage response and cell death to eliminate cells that may have accumulated mutations after multiple divisions. However, telomere elongation is associated with the increased proliferative potential of specific cell types, such as stem and germ cells. This elongation can be permanent in these cells and is activated temporally during immune response activation and regeneration processes. The activation of telomere lengthening mechanisms is coupled with increased proliferation and the cells' need for energy and building resources. To obtain the necessary nutrients, cells are capable of finely regulating energy production and consumption, switching between catabolic and anabolic processes. In this review, we focused on the interconnection between metabolism programs and telomere lengthening mechanisms during programmed activation of proliferation, such as in germ cell maturation, early embryonic development, neoplastic lesion growth, and immune response activation. It is generally accepted that telomere disturbance influences biological processes and promotes dysfunctionality. Here, we propose that metabolic conditions within proliferating cells should be involved in regulating telomere lengthening mechanisms, and telomere length may serve as a marker of defects in cellular functionality. We propose that it is possible to reprogram metabolism in order to regulate the telomere length and proliferative activity of cells, which may be important for the development of approaches to regeneration, immune response modulation, and cancer therapy. However, further investigations in this area are necessary to improve the understanding and manipulation of the molecular mechanisms involved in the regulation of proliferation, metabolism, and aging.

Transcriptomic balance and optimal growth are determined by cell size

Cell size and growth are intimately related across the evolutionary scale, but whether cell size is important to attain maximal growth or fitness is still an open question. We show that growth rate is a non-monotonic function of cell volume, with maximal values around the critical size of wild-type yeast cells. The transcriptome of yeast and mouse cells undergoes a relative inversion in response to cell size, which we associate theoretically and experimentally with the necessary genome-wide diversity in RNA polymerase II affinity for promoters. Although highly expressed genes impose strong negative effects on fitness when the DNA/mass ratio is reduced, transcriptomic alterations mimicking the relative inversion by cell size strongly restrain cell growth. In all, our data indicate that cells set the critical size to obtain a properly balanced transcriptome and, as a result, maximize growth and fitness during proliferation.

Mitochondrial NME6 Influences Basic Cellular Processes in Tumor Cells In Vitro

NME6 belongs to the family of nucleoside diphosphate kinase enzymes, whose major role is to transfer the terminal phosphate from NTPs, mostly ATP, to other (d)NDPs via a high-energy intermediate. Beside this basic enzymatic activity, the family, comprising 10 genes/proteins in humans, executes a number of diverse biochemical/biological functions in the cell. A few previous studies have reported that NME6 resides in the mitochondria and influences oxidative phosphorylation while interacting with RCC1L, a GTPase involved in mitochondrial ribosome assembly and translation. Considering the multifunctional role of NME family members, the goal of the present study was to assess the influence of the overexpression or silencing of NME6 on fundamental cellular events of MDA-MB-231T metastatic breast cancer cells. Using flow cytometry, Western blotting, and a wound-healing assay, we demonstrated that the overexpression of NME6 reduces cell migration and alters the expression of EMT (epithelial-mesenchymal transition) markers. In addition, NME6 overexpression influences cell cycle distribution exclusively upon DNA damage and impacts the MAPK/ERK signaling pathway, while it has no effect on apoptosis. To conclude, our results demonstrate that NME6 is involved in different cellular processes, providing a solid basis for future, more precise investigations of its role.

Novel insight into mitochondrial dynamin-related protein-1 as a new chemo-sensitizing target in resistant cancer cells

Mitochondrial dynamics have pillar roles in several diseases including cancer. Cancer cell survival is monitored by mitochondria which impacts several cellular functions such as cell metabolism, calcium signaling, and ROS production. The equilibrium of death and survival rate of mitochondria is important for healthy cellular processes. Whereas inhibition of mitochondrial metabolism and dynamics can have crucial regulatory decisions between cell survival and death. The steady rate of physiological flux of both mitochondrial fission and fusion is strongly related to the preservation of cellular bioenergetics. Dysregulation of mitochondrial dynamics including fission and fusion is a critical machinery in cells accompanied by crosstalk in cancer progression and resistance. Many cancer cells express high levels of Drp-1 to induce cancer cell invasion, metastasis and chemoresistance including breast cancer, liver cancer, pancreatic cancer, and colon cancer. Targeting Drp-1 by inhibitors such as Midivi-1 helps to enhance the responsiveness of cancer cells towards chemotherapy. The review showed Drp-1 linked processes such as mitochondrial dynamics and relationship with cancer, invasion, and chemoresistance along with computational assessing of all publicly available Drp-1 inhibitors. Drp1-IN-1, Dynole 34-2, trimethyloctadecylammonium bromide, and Schaftoside showed potential inhibitory effects on Drp-1 as compared to standard Mdivi- 1. This emerging approach may have extensive strength in the context of cancer development and chemoresistance and further work is needed to aid in more effective cancer management.

Progesterone boosts abiraterone-driven target and NK cell therapies against glioblastoma

INTRODUCTION

Glioblastoma (GBM) poses a significant challenge in oncology, with median survival times barely extending beyond a year due to resistance to standard therapies like temozolomide (TMZ). This study introduces a novel therapeutic strategy combining progesterone (Prog) and abiraterone (Abi) aimed at enhancing GBM treatment efficacy by modulating the tumor microenvironment and augmenting NK cell-mediated immunity.

METHODS

We employed in vitro and in vivo GBM models to assess the effects of Prog and Abi on cell viability, proliferation, apoptosis, and the immune microenvironment. Techniques included cell viability assays, Glo-caspase 3/7 apoptosis assays, RNA-seq and qPCR for gene expression, Seahorse analysis for mitochondrial function, HPLC-MS for metabolomics analysis, and immune analysis by flow cytometry to quantify NK cell infiltration.

RESULTS

Prog significantly reduced the IC50 of Abi in TMZ-resistant GBM cell, suggesting the enhanced cytotoxicity. Treatment induced greater apoptosis than either agent alone, suppressed tumor growth, and prolonged survival in mouse models. Notably, there was an increase in CD3-/CD19-/CD56+/NK1.1+ NK cell infiltration in treated tumors, indicating a shift towards an anti-tumor immune microenvironment. The combination therapy also resulted in a reduction of MGMT expression and a suppression of mitochondrial respiration and glycolysis in GBM cells.

CONCLUSION

The combination of Prog and Abi represents a promising therapeutic approach for GBM, showing potential in suppressing tumor growth, extending survival, and modulating the immune microenvironment. These findings warrant further exploration into the clinical applicability of this strategy to improve outcomes for GBM patients.

Cellular Energy Cycle Mediates an Advection-Like Forward Cell Flow to Support Collective Invasion

Collective cell migration is a model for nonequilibrium biological dynamics, which is important for morphogenesis, pattern formation, and cancer metastasis. The current understanding of cellular collective dynamics is based primarily on cells moving within a 2D epithelial monolayer. However, solid tumors often invade surrounding tissues in the form of a stream-like 3D structure, and how biophysical cues are integrated at the cellular level to give rise to this collective streaming remains unclear. Here, it is shown that cell cycle-mediated bioenergetics drive a forward advective flow of cells and energy to the front to support 3D collective invasion. The cell division cycle mediates a corresponding energy cycle such that cellular adenosine triphosphate (ATP) energy peaks just before division. A reaction-advection-diffusion (RAD) type model coupled with experimental measurements further indicates that most cells enter an active division cycle at rear positions during 3D streaming. Once the cells progress to a later stage toward division, the high intracellular energy allows them to preferentially stream toward the tip and become leader cells. This energy-driven cellular flow may be a fundamental characteristic of 3D collective dynamics based on thermodynamic principles important for not only cancer invasion but also tissue morphogenesis.

MicroRNA let-7 targets BmCDK1 to regulate cell proliferation and endomitosis of silk gland in the silkworm, Bombyx mori

MicroRNAs play critical roles in multiple developmental processes in insects. Our previous study showed that CRISPR/Cas9-mediated knock down of the microRNA let-7 in silkworms increased the size of larvae and silk glands, thereby improving the silk production capacity. In this study, we elucidate the molecular mechanism underlying of let-7 regulates growth. Identification of differentially expressed genes in response to let-7 knock down revealed enrichment of pathways associated with cell proliferation and DNA replication. let-7 dysregulation affected the cell cycle and proliferation of the Bombyx mori cell line BmN. Dual-luciferase and target site mutation assays showed that BmCDK1 is a direct target gene of let-7, with only 1 binding site on its 3'-untranslated region. RNA interference of BmCDK1 inhibited cell proliferation, but this effect was counteracted by co-transfection with let-7 antagomir. Moreover, let-7 knock down induced BmCDK1 expression and promoted cell proliferation in multiple tissues, and further induced endomitosis in the silk gland in vivo. Knock down of BmCDK1 resulted in abnormal formation of a new epidermis, and larval development was arrested at the 2nd or 3rd molt stage. Taken together, our results demonstrated that BmCDK1 is a novel target of let-7 in cell fate determination, possessing potential for improving silk yield in silkworm.

The Interaction of Calcium-Sensing Receptor with KIF11 Enhances Cisplatin Resistance in Lung Adenocarcinoma via BRCA1/cyclin B1 pathway

Cisplatin (DDP) is commonly used in the treatment of non-small cell lung cancer (NSCLC), including lung adenocarcinoma (LUAD), and the primary cause for its clinical inefficacy is chemoresistance. Here, we aimed to investigate a novel mechanism of chemoresistance in LUAD cells, focusing on the calcium-sensing receptor (CaSR). In this study, high CaSR expression was detected in DDP-resistant LUAD cells, and elevated CaSR expression is strongly correlated with poor prognosis in LUAD patients receiving chemotherapy. LUAD cells with high CaSR expression exhibited decreased sensitivity to cisplatin, and the growth of DDP-resistant LUAD cells was inhibited by cisplatin treatment in combination with CaSR suppression, accompanied by changes in BRCA1 and cyclin B1 protein expression both in vitro and in vivo. Additionally, an interaction between CaSR and KIF11 was identified. Importantly, suppressing KIF11 resulted in decreased protein levels of BRCA1 and cyclin B1, enhancing the sensitivity of DDP-resistant LUAD cells to cisplatin with no obvious decrease in CaSR. Here, our findings established the critical role of CaSR in promoting cisplatin resistance in LUAD cells by modulating cyclin B1 and BRCA1 and identified KIF11 as a mediator, highlighting the potential therapeutic value of targeting CaSR to overcome chemoresistance in LUAD.

Identification of lung adenocarcinoma subtypes based on mitochondrial energy metabolism-related genes

BACKGROUND

Identifying subtypes of lung adenocarcinoma (LUAD) patients based on mitochondrial energy metabolism and immunotherapy sensitivity is essential for precision cancer treatment.

METHODS

LUAD subtypes were identified using unsupervised consensus clustering, and results were subjected to immune and tumor mutation analyses. DEGs between subtypes were identified by differential analysis. Functional enrichment and PPI network analyses were conducted. Patients were classified into high and low expression groups based on the expression of the top 10 hub genes, and survival analysis was performed. Drugs sensitive to feature genes were screened based on the correlation between hub gene expression and drug IC50 value. qRT-PCR and western blot were used for gene expression detection, and CCK-8 and flow cytometry were for cell viability and apoptosis analysis.

RESULTS

Cluster-1 had significantly higher overall survival and a higher degree of immunoinfiltration and immunophenotypic score, but a lower TIDE score, DEPTH score, and TMB. Enrichment analysis showed that pathways and functions of DEGs between two clusters were mainly related to the interaction of receptor ligands with intracellular proteases. High expression of hub genes corresponded to lower patient survival rates. The predicted drugs with high sensitivity to feature genes were CDK1: Ribavirin (0.476), CCNB2: Hydroxyurea (0.474), Chelerythrine (0.470), and KIF11: Ribavirin (0.471). KIF11 and CCNB2 were highly expressed in LUAD cells and promoted cell viability and inhibited cell apoptosis.

CONCLUSION

This study identified two subtypes of LUAD, with cluster-1 being more suitable for immunotherapy. These results provided a reference for the development of precision immunotherapy for LUAD patients.

MAD1 deficiency accelerates hepatocellular proliferation via suppressing TGF-β signaling

Numerous researches have reported on the regulatory network of liver regeneration induced by partial hepatectomy (PH). However, information on key molecules and/or signaling pathways regulating the termination stage of liver regeneration remains limited. In this study, we identify hepatic mitotic arrest deficient 1 (MAD1) as a crucial regulator of transforming growth factor β (TGF-β) in the hepatocyte to repress liver regeneration. MAD1 has a low expression level at the rapid proliferation phase but significantly increases at the termination phase of liver regeneration. We show that MAD1 deficiency accelerates hepatocyte proliferation and enhances mitochondrial biogenesis and respiratory. Mechanistically, MAD1 deficiency in hepatocytes enhances mitochondrial function and promotes hepatocyte proliferation by suppressing TGF-β signaling. Our study reveals MAD1 as a novel suppressor of hepatocyte proliferation, which may provide a new therapeutic target for the recovery of liver function after liver transplant and partial hepatectomy.

Structure-Activity Relationship Study of (E)-3-(6-Fluoro-1H-indol-3-Yl)-2-methyl-1-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (FC116) Against Metastatic Colorectal Cancers Resistant to Oxaliplatin

Advanced metastatic colorectal cancer (mCRC) and the development of drug resistance to chemotherapy pose significant challenges in clinical settings. In previous studies, we have demonstrated the potent cytotoxic activity of (E)-3-(6-fluoro-1H-indol-3-yl)-2-methyl-1-(3,4,5-trimethoxyphenyl)prop-2-en-1-one (FC116) and related 30 derivatives against mCRC by targeting microtubules. In this study, we aimed to evaluate the efficacy of the 31 compounds and explore the structure-activity relationship (SAR) against oxaliplatin-resistant mCRC. We found that most of the derivatives showed high sensitivity toward the oxaliplatin-resistant HCT-116/L cells. Particularly, FC116 exhibited a better GI50 value against the resistant mCRC cell line, HCT-116/L, compared to standard therapies. We also observed a safer therapeutic window for FC116 and a synergistic effect when it was used in combination with oxaliplatin. Mechanistically, FC116 induced the G2/M phase arrest by downregulating cyclin B1 expression through its interaction with microtubules in resistant colorectal cancer cells. Furthermore, in vivo experiments demonstrated that FC116 significantly suppressed tumor growth, achieving a 78% reduction at a dose of 3 mg/kg, which was superior to the 40% reduction achieved by oxaliplatin treatment. Overall, our findings suggest that the indole-chalcone compound FC116 represents a promising lead for chemotherapy in oxaliplatin-resistant mCRC.

Mitochondria-ER contact sites expand during mitosis

Mitochondria-ER contact sites (MERCS) are involved in energy homeostasis, redox and Ca2+ signaling, and inflammation. MERCS are heavily studied; however, little is known about their regulation during mitosis. Here, we show that MERCS expand during mitosis in three cell types using various approaches, including transmission electron microscopy, serial EM coupled to 3D reconstruction, and a split GFP MERCS marker. We further show enhanced Ca2+ transfer between the ER and mitochondria using either direct Ca2+ measurements or by quantifying the activity of Ca2+-dependent mitochondrial dehydrogenases. Collectively, our results support a lengthening of MERCS in mitosis that is associated with improved Ca2+ coupling between the two organelles. This augmented Ca2+ coupling could be important to support the increased energy needs of the cell during mitosis.

Bioinformatics analysis and validation of CSRNP1 as a key prognostic gene in non-small cell lung cancer

Cysteine and serine-rich nuclear protein 1 (CSRNP1) has shown prognostic significance in various cancers, but its role in non-small cell lung cancer (NSCLC) remains elusive. We investigated CSRNP1 expression in NSCLC cases using bioinformatics tools from the GEO public repository and validated our findings through RT-qPCR in tumor and adjacent normal tissues. KEGG and GO enrichment analyses were employed to unveil the significant deregulation in signaling pathways. Additionally, clinical significance of CSRNP1 in NSCLC was determined through receiver operating curve (ROC) analysis, and its impact on survival was assessed using Kaplan-Meier analysis. To explore the functional impact of CSRNP1, we silenced its expression in NSCLC cells and assessed the effects on cell viability, migration, and invasion using MTT, Transwell, and wound-healing assays, respectively. Additionally, we investigated the influence of CSRNP1 silencing on the phosphorylation patterns of critical signaling proteins such as p53, p-Akt, and p-MDM2. Our results demonstrated significantly lower CSRNP1 expression in NSCLC tumor tissues (P < 0.01). ROC analysis indicated that NSCLC patients with high CSRNP1 expression exhibited extended overall survival and disease-free survival. Furthermore, CSRNP1 silencing promoted NSCLC cells viability, migration, and invasion (P < 0.05). Mechanistically, CSRNP1 silencing led to increased phosphorylation of AKT and MDM2, along with a concurrent reduction in p53 protein expression, suggesting its impact on NSCLC through deregulated cell cycle processes. In conclusion, our study underscores the significance of CSRNP1 in NSCLC pathogenesis, offering insights for targeted therapeutic interventions of NSCLC.

Curcumin-Piperlongumine Hybrid Molecule Increases Cell Cycle Arrest and Apoptosis in Lung Cancer through JNK/c-Jun Signaling Pathway

The instability of curcumin's structure and the toxic side effects of piperlongumine have limited their potential applications in cancer treatment. To overcome these challenges, we designed and synthesized a novel curcumin-piperlongumine hybrid molecule, 3-[(E)-4-hydroxy-3-methoxybenzylidene]-1-[(E)-3-(3,4,5-trimethoxyphenyl)acryloyl]piperidin-2-one (CP), using a molecular hybridization strategy. CP exhibited enhanced structural stability and safety compared with its parent compounds. Through in vitro and in vivo biological activity screenings, CP effectively inhibited cell proliferation, caused cell cycle arrest in the G2/M phase, and induced apoptosis. Mechanistically, CP-induced apoptosis was partially mediated by cell cycle arrest. Furthermore, we discovered that CP induces cell cycle arrest and apoptosis through the regulation of JNK signaling. These findings highlight the potential of CP as a promising therapeutic agent for lung cancer treatment.

Kinesin Family Member-18A (KIF18A) Promotes Cell Proliferation and Metastasis in Hepatocellular Carcinoma

BACKGROUND & AIMS

Kinesin family member 18A (KIF18A) is notable for its aberrant expression across various cancer types and its pivotal role is driving cancer progression. In this study, we aim to investigate the intricate molecular mechanisms underlying the impact of KIF18A on the progression of HCC.

METHODS

Western blotting assays, a quantitative real-time PCR and immunohistochemical analyses were performed to quantitatively assess KIF18A expression in HCC tissues. We then performed genetic manipulations within HCC cells by silencing endogenous KIF18A using short hairpin RNA (shRNA) and introducing exogenous plasmids to overexpress KIF18A. We monitored cell progression, analyzed cell cycle and cell apoptosis and assessed cell migration and invasion both in vitro and in vivo. Moreover, we conducted RNA-sequencing to explore KIF18A-related signaling pathways utilizing Reactome and KEGG enrichment methods and validated these critical mediators in these pathways.

RESULTS

Analysis of the TCGA-LIHC database revealed pronounced overexpression of KIF18A in HCC tissues, the finding was subsequently confirmed through the analysis of clinical samples obtained from HCC patients. Notably, silencing KIF18A in cells led to an obvious inhibition of cell proliferation, migration and invasion in vitro. Furthermore, in subcutaneous and orthotopic xenograft models, suppression of KIF18A sgnificantly redudce tumor weight and the number of lung metastatic nodules. Mechanistically, KIF18A appears to facilitate cell proliferation by upregulating MAD2 and CDK1/CyclinB1 expression levels, with the activation of SMAD2/3 signaling contributing to KIF18A-driven metastasis.

CONCLUSION

Our study elucidates the molecular mechanism by which KIF18A mediates proliferation and metastasis in HCC cells, offering new insights into potential therapeutic targets.

The Mitochondrial Connection: The Nek Kinases' New Functional Axis in Mitochondrial Homeostasis

Mitochondria provide energy for all cellular processes, including reactions associated with cell cycle progression, DNA damage repair, and cilia formation. Moreover, mitochondria participate in cell fate decisions between death and survival. Nek family members have already been implicated in DNA damage response, cilia formation, cell death, and cell cycle control. Here, we discuss the role of several Nek family members, namely Nek1, Nek4, Nek5, Nek6, and Nek10, which are not exclusively dedicated to cell cycle-related functions, in controlling mitochondrial functions. Specifically, we review the function of these Neks in mitochondrial respiration and dynamics, mtDNA maintenance, stress response, and cell death. Finally, we discuss the interplay of other cell cycle kinases in mitochondrial function and vice versa. Nek1, Nek5, and Nek6 are connected to the stress response, including ROS control, mtDNA repair, autophagy, and apoptosis. Nek4, in turn, seems to be related to mitochondrial dynamics, while Nek10 is involved with mitochondrial metabolism. Here, we propose that the participation of Neks in mitochondrial roles is a new functional axis for the Nek family.

An iron rheostat controls hematopoietic stem cell fate

Mechanisms governing the maintenance of blood-producing hematopoietic stem and multipotent progenitor cells (HSPCs) are incompletely understood, particularly those regulating fate, ensuring long-term maintenance, and preventing aging-associated stem cell dysfunction. We uncovered a role for transitory free cytoplasmic iron as a rheostat for adult stem cell fate control. We found that HSPCs harbor comparatively small amounts of free iron and show the activation of a conserved molecular response to limited iron-particularly during mitosis. To study the functional and molecular consequences of iron restriction, we developed models allowing for transient iron bioavailability limitation and combined single-molecule RNA quantification, metabolomics, and single-cell transcriptomic analyses with functional studies. Our data reveal that the activation of the limited iron response triggers coordinated metabolic and epigenetic events, establishing stemness-conferring gene regulation. Notably, we find that aging-associated cytoplasmic iron loading reversibly attenuates iron-dependent cell fate control, explicating intervention strategies for dysfunctional aged stem cells.

Molecular mechanism of human ISG20L2 for the ITS1 cleavage in the processing of 18S precursor ribosomal RNA

The exonuclease ISG20L2 has been initially characterized for its role in the mammalian 5.8S rRNA 3' end maturation, specifically in the cleavage of ITS2 of 12S precursor ribosomal RNA (pre-rRNA). Here, we show that human ISG20L2 is also involved in 18S pre-rRNA maturation through removing the ITS1 region, and contributes to ribosomal biogenesis and cell proliferation. Furthermore, we determined the crystal structure of the ISG20L2 nuclease domain at 2.9 Å resolution. It exhibits the typical αβα fold of the DEDD 3'-5' exonuclease with a catalytic pocket located in the hollow near the center. The catalytic residues Asp183, Glu185, Asp267, His322 and Asp327 constitute the DEDDh motif in ISG20L2. The active pocket represents conformational flexibility in the absence of an RNA substrate. Using structural superposition and mutagenesis assay, we mapped RNA substrate binding residues in ISG20L2. Finally, cellular assays revealed that ISG20L2 is aberrantly up-regulated in colon adenocarcinoma and promotes colon cancer cell proliferation through regulating ribosome biogenesis. Together, these results reveal that ISG20L2 is a new enzymatic member for 18S pre-rRNA maturation, provide insights into the mechanism of ISG20L2 underlying pre-rRNA processing, and suggest that ISG20L2 is a potential therapeutic target for colon adenocarcinoma.

Neutrophil Extracellular Traps Upregulate p21 and Suppress Cell Cycle Progression to Impair Endothelial Regeneration after Inflammatory Lung Injury

Background: Sepsis is a major cause of ICU admissions, with high mortality and morbidity. The lungs are particularly vulnerable to infection and injury, and restoration of vascular endothelial homeostasis after injury is a crucial determinant of outcome. Neutrophil extracellular trap (NET) release strongly correlates with the severity of lung tissue damage. However, little is known about whether NETs affect endothelial cell (EC) regeneration and repair. Methods: Eight- to ten-week-old male C57BL/6 mice were injected intraperitoneally with a sublethal dose of LPS to induce acute lung inflammatory injury or with PBS as a control. Blood samples and lung tissues were collected to detect NET formation and lung endothelial cell proliferation. Human umbilical vein endothelial cells (HUVECs) were used to determine the role of NETs in cell cycle progression in vitro. Results: Increased NET formation and impaired endothelial cell proliferation were observed in mice with inflammatory lung injury following septic endotoxemia. Degradation of NETs with DNase I attenuated lung inflammation and facilitated endothelial regeneration. Mechanistically, NETs induced p21 upregulation and cell cycle stasis to impair endothelial repair. Conclusions: Our findings suggest that NET formation impairs endothelial regeneration and vascular repair through the induction of p21 and cell cycle arrest during inflammatory lung injury.

Developmental regulation of cellular metabolism is required for intestinal elongation and rotation

Malrotation of the intestine is a prevalent birth anomaly, the etiology of which remains poorly understood. Here, we show that late-stage exposure of Xenopus embryos to atrazine, a widely used herbicide that targets electron transport chain (ETC) reactions, elicits intestinal malrotation at high frequency. Interestingly, atrazine specifically inhibits the cellular morphogenetic events required for gut tube elongation, including cell rearrangement, differentiation and proliferation; insufficient gut lengthening consequently reorients the direction of intestine rotation. Transcriptome analyses of atrazine-exposed intestines reveal misexpression of genes associated with glycolysis and oxidative stress, and metabolomics shows that atrazine depletes key glycolytic and tricarboxylic acid cycle metabolites. Moreover, cellular bioenergetics assays indicate that atrazine blocks a crucial developmental transition from glycolytic ATP production toward oxidative phosphorylation. Atrazine-induced defects are phenocopied by rotenone, a known ETC Complex I inhibitor, accompanied by elevated reactive oxygen species, and rescued by antioxidant supplementation, suggesting that malrotation may be at least partly attributable to redox imbalance. These studies reveal roles for metabolism in gut morphogenesis and implicate defective gut tube elongation and/or metabolic perturbations in the etiology of intestinal malrotation.

CDCA8, a mitosis-related gene, as a prospective pan-cancer biomarker: implications for survival prognosis and oncogenic immunology

BACKGROUND

Human cell division cycle-associated protein 8 (CDCA8), a critical regulator of mitosis, has been identified as a prospective prognostic biomarker in several cancer types, including breast, colon, and lung cancers. This study analyzed the diagnostic/prognostic potential and clinical implications of CDCA8 across diverse cancers.

METHODS

Bioinformatics and molecular experiments.

RESULTS

Analyzing TCGA data via TIMER2 and GEPIA2 databases revealed significant up-regulation of CDCA8 in 23 cancer types compared to normal tissues. Prognostically, elevated CDCA8 expression correlated with poorer overall survival in KIRC, LUAD, and SKCM, emphasizing its potential as a prognostic marker. UALCAN analysis demonstrated CDCA8 up-regulation based on clinical variables, such as cancer stage, race, and gender, in these cancers. Epigenetic exploration indicated reduced CDCA8 promoter methylation levels in Kidney Renal Clear Cell Carcinoma (KIRC), Lung Adenocarcinoma (LUAD), and Skin Cutaneous Melanoma (SKCM) tissues compared to normal controls. Promoter methylation and mutational analyses showcased a hypomethylation and low mutation rate for CDCA8 in these cancers. Correlation analysis revealed positive associations between CDCA8 expression and infiltrating immune cells, particularly CD8+ and CD4+ T cells. Protein-protein interaction (PPI) network analysis unveiled key interacting proteins, while gene enrichment analysis highlighted their involvement in crucial cellular processes and pathways. Additionally, exploration of CDCA8-associated drugs through DrugBank presented potential therapeutic options for KIRC, LUAD, and SKCM. In vitro validation using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) confirmed elevated CDCA8 expression in LUAD cell lines (A549 and H1299) compared to control cell lines (Beas-2B and NL-20).

CONCLUSION

This study provides concise insights into CDCA8's multifaceted role in KIRC, LUAD, and SKCM, covering expression patterns, diagnostic and prognostic relevance, epigenetic regulation, mutational landscape, immune infiltration, and therapeutic implications.

Aurora kinase B disruption suppresses pathological retinal angiogenesis by affecting cell cycle progression

PURPOSE

The detrimental effects of pathological angiogenesis on the visual function are indisputable. Within a prominent role in chromosome segregation and tumor progression, aurora kinase B (AURKB) assumes a prominent role. However, its role in pathological retinal angiogenesis remains unclear. This study explores this latent mechanism.

METHODS

To inhibit AURKB expression, we designed specific small interfering RNAs targeting AURKB and transfected them into vascular endothelial cells. Barasertib was selected as the AURKB inhibitor. The anti-angiogenic effects of both AURKB siRNA and barasertib were assessed in vitro by cell proliferation, transwell migration, and tube formation. To evaluate the angiogentic effects of AURKB in vivo, neonatal mice were exposed to 75% oxygen followed by normoxic repositioning to establish an oxygen-induced retinopathy (OIR) model. Subsequently, phosphate-buffered saline and barasertib were administered into OIR mice via intravitreal injection. The effects of AURKB on cell cycle proteins were determined by western blot analysis.

RESULTS

We found that AURKB was overexpressed during pathological angiogenesis. AURKB siRNA and barasertib significantly inhibited endothelial cell proliferation, migration, and tube formation in vitro. Furthermore, AURKB inhibition attenuated retinal angiogenesis in the OIR model. A possible mechanism is the disruption of cell cycle by AURKB inhibition.

CONCLUSION

In conclusion, AURKB significantly influenced pathological retinal angiogenesis, thereby presenting a promising therapeutic target in ocular neovascular diseases.

The bidirectional relationship between metabolism and cell cycle control

The relationship between metabolism and cell cycle progression is complex and bidirectional. Cells must rewire metabolism to meet changing biosynthetic demands across cell cycle phases. In turn, metabolism can influence cell cycle progression through direct regulation of cell cycle proteins, through nutrient-sensing signaling pathways, and through its impact on cell growth, which is linked to cell division. Furthermore, metabolism is a key player in mediating quiescence-proliferation transitions in physiologically important cell types, such as stem cells. How metabolism impacts cell cycle progression, exit, and re-entry, as well as how these processes impact metabolism, is not fully understood. Recent advances uncovering mechanistic links between cell cycle regulators and metabolic processes demonstrate a complex relationship between metabolism and cell cycle control, with many questions remaining.

FEN1 Promotes Hepatocellular Carcinoma Progression by Activating Cell Cycle Transition from G2 To M Phase

Flap endonuclease 1 (FEN1) is a structure-specific nuclease that is involved in the occurrence and development of various types of tumors. Previous studies have shown that FEN1 plays an important role in the development of hepatocellular carcinoma, however, the molecular mechanisms remain fully elucidated, especially its effect on the cell cycle of hepatocellular carcinoma has not been investigated. In this study, via bioinformatics prediction and clinical specimen verification, we confirmed that FEN1 was highly expressed in HCC and correlated with poor prognosis. The knockdown or overexpression of FEN1 could inhibit or promote the proliferation and invasion of HCC cells. Importantly, cell cycle and functional experiments showed that FEN1 could promote cell proliferation by inducing cell cycle transition from G2 to M phase. Further studies indicated that FEN1 regulated the G2/M transition by modulating cell division cycle 25C (Cdc25C), cyclin-dependent kinase 1 (CDK1) and Cyclin B1 expressions. To sum up, our research suggested that FEN1 could promote the proliferation, migration and invasion of HCC cells via activating cell cycle progression from G2 to M phase, indicating that FEN1 may be a potential target for the treatment of HCC.

VT204: A Potential Small Molecule Inhibitor Targeting KRASG12C Mutation for Therapeutic Intervention in Non-Small Cell Lung Cancer

Objectives: The development of effective treatments for non-small cell lung cancer (NSCLC), particularly targeting the KRASG12C mutation, remains a challenge. In this study, we investigated the therapeutic potential of VT204, a small molecule inhibitor of KRASG12C, in NSCLC. Methods: To achieve the objectives, we conducted a comprehensive set of experimental methods. In vitro experiments involved the investigation of VT204 on proliferation, apoptosis, cell cycle dynamics, migration, invasion, and on the RAF/MEK/ERK signaling pathway in NCI-H358 cells. In addition, in vivo experiments were performed to evaluate the influence of VT204 on tumor growth. Results: We demonstrated that VT204 effectively suppressed cell proliferation in NCI-H358 cells, with significant inhibition observed at a concentration of 8 μM. Colony formation assays further supported the inhibitory effect of VT204 on NCI-H358 cell growth. Moreover, VT204 exhibited notable effects on suppressing migration and invasion capacities of NCI-H358 cells, indicating its potential as a metastasis-inhibiting agent. Mechanistic investigations revealed that VT204 induced apoptosis and G2M-phase cell cycle arrest in NCI-H358 cells. Additionally, VT204 modulated the RAF/MEK/ERK signaling pathway, leading to reduced phosphorylation of ERK. In vivo studies using xenograft models confirmed the inhibitory effect of VT204 on NCI-H358 tumor growth. Conclusion: These findings highlight VT204 as a promising therapeutic candidate for NSCLC targeting the KRASG12C mutation.

Bioinformatics Approach to Identify the Influences of COVID-19 on Ischemic Stroke

As severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) is becoming more infectious and less virulent, symptoms beyond the lungs of the Coronavirus Disease 2019 (COVID-19) patients are a growing concern. Studies have found that the severity of COVID-19 patients is associated with an increased risk of ischemic stroke (IS); however, the underlying pathogenic mechanisms remain unknown. In this study, bioinformatics approaches were utilized to explore potential pathogenic mechanisms and predict potential drugs that may be useful in the treatment of COVID-19 and IS. The GSE152418 and GSE122709 datasets were downloaded from the GEO website to obtain the common differentially expressed genes (DEGs) of the two datasets for further functional enrichment, pathway analysis, and drug candidate prediction. A total of 80 common DEGs were identified in COVID-19 and IS datasets for GO and KEGG analysis. Next, the protein-protein interaction (PPI) network was constructed and hub genes were identified. Further, transcription factor-gene interactions and DEGs-miRNAs coregulatory network were investigated to explore their regulatory roles in disease. Finally, protein-drug interactions with common DEGs were analyzed to predict potential drugs. We successfully identified the top 10 hub genes that could serve as novel targeted therapies for COVID-19 and screened out some potential drugs for the treatment of COVID-19 and IS.

Identification of metabolism-related gene signature in lung adenocarcinoma

AIM

Lung cancer is one of the most common cancers in China and has a high mortality rate. Most patients who are diagnosed have lost the opportunity to undergo surgery. Aberrant metabolism is closely associated with tumorigenesis. We aimed to identify an effective metabolism-related prediction model for assessing prognosis based on the cancer genome atlas (TCGA) and GSE116959 databases.

METHODS

TCGA and GSE116959 datasets from Gene Expression Omnibus were used to obtain lung adenocarcinoma (LUAD) data. Additionally, we captured metabolism-related genes (MRGs) from the GeneCards database. First, we extracted differentially expressed genes using R to analyze the LUAD data. We then selected the same differentially expressed genes, including 168 downregulated and 77 upregulated genes. Finally, 218 differentially expressed MRGs (DEMRGs) were included to perform functional enrichment analysis and construct a protein-protein interaction network with the help of Cytoscape and Search Tool for the Retrieval of Interacting Genes database. Cytoscape was used to visualize the intensive intervals in the network. Then univariate and Least Absolute Shrinkage and Selection Operator Cox regression analyses, which assisted in identifying the overall survival (OS)-related DEMRGs and building a 10-DEMRG prognosis model, were performed. The prognostic values, tumor immunity relevance, and molecular mechanism were further investigated. A nomogram incorporating signature, age, gender, and TNM stage was established.

RESULTS

A 10-DEMRG model was established to forecast the OS of LUAD through Least Absolute Shrinkage and Selection Operator regression analysis. This prognostic signature stratified LUAD patients into low-risk and high-risk groups. The receiver operating characteristic curve and K-M analysis indicated good performance of the DEMRGs signature at predicting OS in the TCGA dataset. Univariate and multivariate Cox regression also revealed that the DEMRGs signature was an independent prognosis factor in LUAD. We noticed that the risk score was substantially related to the clinical parameters of LUAD patients, covering age and stage. Immune analysis results showed that risk score was associated with some immune cells and immune checkpoints. Nomogram also verified the clinical value of the DEMRGs signature.

CONCLUSION

In this study, we constructed a DEMRGs signature and established a prognostic nomogram that is robust and reliable to predict OS in LUAD. Overall, the findings could help with therapeutic customization and personalized therapies.

Hepatoprotective effect of syringin combined with costunolide against LPS-induced acute liver injury in L-02 cells via Rac1/AKT/NF-κB signaling pathway

Acute liver injury (ALI) leads to abnormal liver function and damage to liver cells. Syringin (syr) and costunolide (cos) are the major extracts from Dolomiaea souliei (Franch.) C.Shih (D. souliei), showing diverse biological functions in various biological processes. We explored the underlying hepatoprotective effects of syr+cos against LPS-induced ALI. Cell viability and proliferation were assessed using an MTT assay and immunofluorescence staining. Flow cytometry analysis was used to detect cell cycle distribution and apoptosis. ELISA was utilized to measure liver function and antioxidant stress indexes. qRT-PCR and western blotting was performed to determine mRNA and protein levels respectively. Using shRNA approach to Rac1 analyzed transcriptional targets. The results showed that syr+cos promoted L-02 cell proliferation, inhibiting the cell apoptosis and blocking cell cycle in G1 and G2/M phase. Syr+cos decreased the production of ALT, AST, LDH, MDA and ROS while increased SOD and CAT activities. Pretreated with syr+cos may decrease expressions of caspase-3,7,9, NF-κB, TNF-α proteins, Cyclin B, CDK1 and p-IκB proteins while p-IκB increased. Silencing of Rac-1 may protect the liver by increasing AKT, S473, T308 and reducing p-AKT proteins. Syr+cos exhibits anti-ALI activity via Rac1/AKT/NF-κB signaling pathway which might act as an effective candidate drug for the treatment of ALI.

The mystery of phospho-Drp1 with four adaptors in cell cycle: when mitochondrial fission couples to cell fate decisions

Recent study had deepened our knowledge of the mitochondrial dynamics to classify mitochondrial fission into two types. To further clarify the relationship between the two distinct fission machinery and the four major adaptors of Drp1, we propose a model of mechanism elucidating the multiple functions of phospho-Drp1 with its adaptors during cell cycle and providing in-depth insights into the molecular basis and evolutionary implications in depth. The model highlights not only the clustering characteristics of different phospho-Drp1 with respective subsets of mitochondrial pro-fission adaptors but also the correlation, crosstalk and shifting between different clustering of phosphorylated Drp1-adaptors during different key fission situations. Particularly, phospho-Drp1 (Ser616) couples with Mff/MiD51 to exert mitochondrial division and phospho-Drp1 (Ser637) couples with MiD49/Fis1 to execute mitophagy in M-phase. We then apply the model to address the relationship of mitochondrial dynamics to Parkinson's disease (PD) and carcinogenesis. Our proposed model is indeed compatible with current research results and pathological observations, providing promising directions for future treatment design.

The Cyclin-dependent kinase 1: more than a cell cycle regulator

The Cyclin-dependent kinase 1, as a serine/threonine protein kinase, is more than a cell cycle regulator as it was originally identified. During the last decade, it has been shown to carry out versatile functions during the last decade. From cell cycle control to gene expression regulation and apoptosis, CDK1 is intimately involved in many cellular events that are vital for cell survival. Here, we provide a comprehensive catalogue of the CDK1 upstream regulators and substrates, describing how this kinase is implicated in the control of key 'cell cycle-unrelated' biological processes. Finally, we describe how deregulation of CDK1 expression and activation has been closely associated with cancer progression and drug resistance.

A pancancer analysis of the oncogenic role of cyclin B1 (CCNB1) in human tumors

Aberrant levels of the G2/M cyclin cyclin B1 (gene CCNB1) have been associated with multiple cancers; however, the literature lacks a focused and comprehensive analysis of the regulation of this important regulator of cell proliferation in cancer. Through this work, we performed a pancancer analysis of the levels of CCNB1 and dissected aspects of regulation and how this correlates with cancer prognosis. We comprehensively evaluated the expression and promoter methylation of CCNB1 across 38 cancers based on RNA sequencing data obtained from the Cancer Genome Atlas (TCGA). The correlation of CCNB1 with prognosis and the tumor microenvironment was explored. Using lung adenocarcinoma data, we studied the potential upstream noncoding RNAs involved in the regulation of CCNB1 and validated the protein levels and prognostic value of CCNB1 for this disease site. CCNB1 was highly expressed, and promoter methylation was reduced in most cancers. Gene expression of CCNB1 correlated positively with poor prognosis of tumor patients, and these results were confirmed at the protein level using lung adenocarcinoma. CCNB1 expression was associated with the infiltration of T helper cells, and this further correlated with poor prognosis for certain cancers, including renal clear cell carcinoma and lung adenocarcinoma. Subsequently, we identified a specific upstream noncoding RNA contributing to CCNB1 overexpression in lung adenocarcinoma through correlation analysis, expression analysis and survival analysis. This study provides a comprehensive analysis of the expression and methylation status of CCNB1 across several forms of cancer and provides further insight into the mechanistic pathways regulating Cyclin B1 in the tumorigenesis process.