Cell Cycle Progression Research Articles

Combination of cisplatin and ethyl acetate extract of Vernonia amygdalina Delile induces cell cycle arrest and apoptosis on PANC-1 cells via PI3K/mTOR

Context: Vernonia amygdalina Delile (VAD) is known as a potential plant with a wide variety of medicinal properties, including anticancer. Aims: To evaluate the combination effect of VAD extract with cisplatin (CIS) against PANC-1 cells, focusing on cell cycle arrest and apoptosis activities. Methods: This study is an experimental study using PANC-1 cells as objects. The phytochemical compounds were analyzed with LC-MS/MS. The cytotoxic activity of extracts and their combinations was determined using the MTT assay method in the PANC-1 cell line. Apoptosis, cell cycle arrest, and PI3K/mTOR profiles were analyzed with flow cytometry. Immunocytochemistry was used to determine Bcl-2, Cyclin D1, and p53 expression. Results: The phytochemicals found were five compounds with retention times of 8.96, 9.85, 10.52, 12.59, and 10.36. The results of the MTT assay showed that the IC50 values of extract and CIS were 21.83 ± 0.46 µg/mL and 3.02 ± 0.44 µg/mL, respectively. The combination index (CI) value of extract and CIS had a synergistic effect. Combination extract and CIS induced early and late apoptosis, inhibited cell cycle progression on the G1 phase, inhibited Bcl-2 and cyclin D1 expression, induced p53 expression, and inhibited PI3K and mTOR expression. Conclusions: The combination of extract and CIS showed anticancer activity against PANC-1 cells through induction of apoptosis and cell cycle arrest via inhibition of PI3K and mTOR expressions.

Resmethrin induces implantation failure by disrupting calcium homeostasis and forcing mitochondrial defects in porcine trophectoderm and uterine luminal epithelial cells

Resmethrin, a type I pyrethroid insecticide, is frequently used globally in residential and farmland areas to control pests. Owing to the repeated administration of resmethrin, and particularly because of its lipophilic nature, residues have been detected in various environments, crops, and livestock. Previous studies have shown the adverse effects of resmethrin, including neurotoxicity and hepatotoxicity. However, the toxic effects of resmethrin on the female reproductive system have rarely been investigated. In the present study, we used two cell types, porcine trophectoderm (pTr) and porcine uterine luminal epithelial (pLE) cells, to examine the toxic effects of resmethrin on implantation and its mechanisms. Our study showed that resmethrin exposure induced apoptosis and inhibited cell cycle progression, thereby reducing the viability of both cell types. In addition, calcium homeostasis was disrupted following resmethrin treatment, and disrupted calcium homeostasis impaired the mitochondrial membrane potential and mitochondrial respiration. In addition to mitochondrial dysfunction, GRP75 and ER stress–related proteins were upregulated. Furthermore, the AKT and MAPK cascades were altered, and reactive oxygen species production and inflammation occurred after resmethrin treatment. Ultimately, through various mechanisms, resmethrin decreased the migratory abilities, and it could diminish the crosstalk between the two cell lines and lower the probability of successful implantation. Overall, we demonstrated that resmethrin interfered with the implantation process by triggering various toxic mechanisms. This study presents, for the first time, evidence regarding the mechanisms through which resmethrin exerts toxic effects on the female reproductive system, thereby raising awareness regarding the potential implications of its widespread use.

A novel EZH1/2 dual inhibitor inhibits GCB DLBCL through Cell Cycle Regulation and M2 Tumor-Associated Macrophage Polarization

The incidence of germinal center B-cell-like type diffuse large B-cell lymphoma (GCB DLBCL) is steadily increasing, with a known hereditary component. Although some molecular mechanisms in GCB DLBCL have been elucidated, understanding remains incomplete, limiting the effectiveness of targeted therapies. In GCB DLBCL patients, abnormally high expression of zeste homologs 2 (EZH2) is noted, and the compensatory effect of EZH1 following EZH2 inhibition contributes to poor prognosis. This highlights the potential of dual targeting of EZH1/2 as a promising strategy. In this study, we developed a novel inhibitor, EZH-1-P2, targeting EZH1/2, and evaluated its anti-tumor effects on DLBCL cells. Mechanistically, inhibition of EZH1/2 affects the epigenetic regulation of gene expression related to p53, impacting cell cycle progression and GCB DLBCL cell growth. Additionally, while EZH1/2 inhibition impacts NOTCH signaling, the precise mechanism by which it affects M2-type tumor-associated macrophage (M2-TAM) polarization and germinal center expansion requires further investigation. Our research introduces EZH-1-P2 as a novel inhibitor with potential as a candidate for GCB DLBCL therapy, although further studies are needed to fully elucidate its mechanisms.

Participation of the insulin-like growth factor system in the early maturity in juvenile male European sea bass

It is known that the insulin-like growth factor (Igf) system is involved in gonadal development and, in turn, reproduction in vertebrates. In this study, the circulating levels of Igf-1 and follicle-stimulating hormone (Fsh) were assessed as physiological signals related to gonadal maturation stage in juvenile male European sea bass at 1 year of age. The seasonal profiles of Igf-1 and Fsh were analyzed in non-precocious (NP) and precocious (PR) fish during the early onset of puberty. Subsequently, gonadal expression patterns of the three igf genes and their two receptors, igf-1r and igf-2r, were studied during their first year of life. The analysis was continued to evaluate the mRNA expression profiles of three genes (sox17, scf, nf2) mediating spermatogenesis progression. Collectively, these results demonstrated that PR males have higher circulating levels of Igf-1 as compared to NP fish before and during the putative gonadal development period (PGD). Plasma Fsh levels were significantly higher in PR males as compared to NP fish before the start of the PGD period, although this was followed by a decrease in Fsh levels and a subsequent recovery, coinciding with the reproductive season (February). Results showed that the total variance associated with the appearance of precocity may be explained by the contribution of factors such as body size and plasma levels of Igf-1, Fsh and sex steroids in male sea bass. Expression of igfs was high during stage I, and this was significantly correlated with the expression of genes related to cell cycle progression, including sox17, scf and nf2. Finally, the decreased expression of all these gonadal factors in precocious animals suggests their potential involvement in regulating the proliferative growth of spermatogonia and supporting cells during the early stages of spermatogenesis, thus evoking the onset of puberty in male sea bass.

Piperine Enhances the Anticancer Effects of Cisplatin on Tongue Squamous Cell Carcinoma Cell Line by Inducing Cell Apoptosis.

Oral squamous cell carcinoma is ranked as the predominant type of head and neck squamous cell carcinoma, comprising roughly 90% of all oral cancer cases. Natural products have proven to be highly valuable as complementary, or adjunctive in the treatment of cancer. Piperine, a natural compound derived from Piper nigrum, demonstrates anti-proliferative and anti-neoplastic effects across various types of cancer. This study focused on assessing the cytotoxic effect of piperine in conjunction with cisplatin within the OSCC cell line. In this in-vitro study, cultured OSCC cells were divided into four groups: a control group (untreated), a group exposed solely to piperine, a group exposed solely to cisplatin, and a group receiving both piperine and cisplatin. Cell viability was determined by the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide (MTT) assay technique. Additionally, flow cytometric analysis was employed to examine cell cycle progression and apoptosis. Assessment of reactive oxygen species activity, morphological changes, and nuclear area factor measurements were carried out. Expression of the apoptotic regulator Bax was assessed through western blotting analysis. Piperine has cytotoxic and apoptotic effects in a concentration-dependent manner. Piperine in combination with cisplatin exhibited a synergistic effect, resulting in more pronounced inhibition of cell viability in OSCC cells compared to using piperine and cisplatin alone. Piperine and cisplatin for 24 h induced apoptosis strongly by increasing Bax protein and ROS activity. Combining piperine with cisplatin demonstrated a greater effectiveness in triggering apoptosis in OSCC cells compared to using cisplatin alone, allowing for a reduction.

CD147 mediates S protein pseudovirus of SARS-CoV-2 infection and its induction of spermatogonia apoptosis.

Male cases diagnosed COVID-19 with more complications and higher mortality compared with females, and the overall consequences of male sex hormones and semen parameters deterioration were observed in COVID-19 patients, whereas the involvement and mechanism for spermatogenic cell remains unclear. The study was aimed to investigate the infection mode of S protein (D614G) pseudovirus (pseu-S-D614G) to spermatogenic cells, as well as the influence on cell growth. Both mouse spermatogonia (GC-1 cell, immortalized spermatogonia) and spermatocyte (GC-2 cell, immortalized spermatocytes) were used to detect the infection of pseu-S-D614G of SARS-CoV-2, and further explored the effect of SARS-CoV-2-spike protein (S-protein) and SARS-CoV-2-spike protein (omicron) (O-protein) on GC-1 cell apoptosis and proliferation. The data showed that the pseu-S-D614G invaded into GC-1 cells through either human ACE2 (hACE2) or human CD147 (hCD147), whereas GC-2 cells were insensitive to viral infection. In addition, the apoptosis and proliferation suppression inflicted by S-protein and O-protein on GC-1 cells was through Bax-Caspase3 signaling rather than arresting cell cycle progression. These findings suggest that CD147, apart from ACE2, may be a potential receptor for SARS-CoV-2 infection in testicular tissues, and that the apoptotic effect was induced in spermatogonia cells by S-protein or O-protein, eventually resulted in the damage to male fertility.

MAFB-mediated CEBPA regulated human urothelium growth through Wnt/β-catenin signaling pathway

MAFB is essential for regulating male-type urethral differentiation, and especially, its variation can contribute to hypospadias in mice. However, the potential mechanism is still unclear. Here we observed that the basic leucine zipper (bZIP) transcription factor MAFB and CCAAT/enhancer-binding protein alpha (CEBPA) could promote human urothelium SV-HUC-1 growth. Moreover, MAFB and CEBPA expression were reduced in the prepuce tissues of hypospadias patients. Based on transcriptome sequencing analysis and Western blot, MAFB knockdown was found to suppress CEBPA protein expression and repress Wnt/β-catenin signaling in urothelium cells. Meanwhile, we observed blocked cell-cycle progression from the G1 to the S phase, inhibited cell proliferation, and activated apoptosis. Furthermore, MAFB could facilitate CEBPA transcription and regulate the proliferation of urothelium. The above results indicated that MAFB-mediated inhibition of urothelial SV-HUC-1 growth resulted from inhibiting the Wnt/β-catenin signaling pathway by down-regulating CEBPA. Our findings provide new insight into the understanding of genes associated with hypospadias and the pathogenic mechanism of this disorder.

Exploring the therapeutic potential of simvastatin in pancreatic neuroendocrine neoplasms: insights into cell cycle regulation and apoptosis.

Pancreatic neuroendocrine neoplasm (pNEN) poses significant challenges in clinical management due to their heterogeneity and limited treatment options. In this study, we investigated the potential of simvastatin (SIM) as an anti-tumor agent in pNEN. We conducted cell culture experiments using QGP-1 and BON-1 cell lines and assessed cell viability, proliferation, migration, and invasion following SIM treatment. To further validate our findings, we performed in vivo experiments using a mouse xenograft model. Additionally, we investigated the underlying molecular mechanisms by analyzing changes in cell cycle progression, apoptosis, and signaling pathways. SIM treatment suppresses pNEN growth both in vitro and in vivo, and led to G1 phase arrest in QGP-1 cells. In contrast, SIM affected both the G1-S and G2-M phase transitions in the BON-1 cell line and induced apoptosis, indicating diverse mechanisms of action. Furthermore, SIM treatment resulted in decreased expression of mutant p53 (mutp53) in BON-1 cells, suggesting a potential therapeutic strategy targeting mutp53. Modulation of the MAPK pathway was also implicated in QGP-1 cells. Our study highlights SIM as a promising candidate for pNEN treatment by inducing cell cycle arrest or apoptosis, potentially through the p53 and MAPK pathways. Further research is warranted to fully elucidate SIM's mechanisms of action and evaluate its therapeutic potential in clinical settings.

AC099850.3 promotes HBV-HCC cell proliferation and invasion through regulating CD276: a novel strategy for sorafenib and immune checkpoint combination therapy

BackgroundThis study investigates the molecular mechanisms of CC@AC&SF@PP NPs loaded with AC099850.3 siRNA and sorafenib (SF) for improving hepatitis B virus-related hepatocellular carcinoma (HBV-HCC).MethodsA dataset of 44 HBV-HCC patients and their survival information was selected from the TCGA database. Immune genes related to survival status were identified using the ImmPort database and WGCNA analysis. A prognostic risk model was constructed and analyzed using Lasso regression. Differential analysis was performed to screen key genes, and their significance and predictive accuracy for HBV-HCC were validated using Kaplan–Meier survival curves, ROC analysis, CIBERSORT analysis, and correlation analysis. The correlation between AC099850.3 and the gene expression matrix was calculated, followed by GO and KEGG enrichment analysis using AC099850.3 and its co-expressed genes. HepG2.2.15 cells were selected for in vitro validation, and lentivirus interference, cell cycle determination, CCK-8 experiments, colony formation assays, Transwell experiments, scratch experiments, and flow cytometry were performed to investigate the effects of key genes on HepG2.2.15 cells. A subcutaneous transplanted tumor model in mice was constructed to verify the inhibitory effect of key genes on HBV-HCC tumors. Subsequently, pH-triggered drug release NPs (CC@AC&SF@PP) were prepared, and their therapeutic effects on HBV-HCC in situ tumor mice were studied.ResultsA prognostic risk model (AC012313.9, MIR210HG, AC099850.3, AL645933.2, C6orf223, GDF10) was constructed through bioinformatics analysis, showing good sensitivity and specificity in diagnostic prediction. AC099850.3 was identified as a key gene, and enrichment analysis revealed its impact on cell cycle pathways. In vitro cell experiments demonstrated that AC099850.3 promotes HepG2.2.15 cell proliferation and invasion by regulating immune checkpoint CD276 expression and cell cycle progression. In vivo, subcutaneously transplanted tumor experiments showed that AC099850.3 promotes the growth of HBV-HCC tumors in nude mice. Furthermore, pH-triggered drug release NPs (CC@AC&SF@PP) loaded with AC099850.3 siRNA and SF were successfully prepared and delivered to the in situ HBV-HCC, enhancing the effectiveness of combined therapy for HBV-HCC.ConclusionsAC099850.3 accelerates the cell cycle progression and promotes the occurrence and development of HBV-HCC by upregulating immune checkpoint CD276 expression. CC@AC&SF@PP NPs loaded with AC099850.3 siRNA and SF improve the effectiveness of combined therapy for HBV-HCC.

Inhibition of PRMT5 moderately suppresses prostate cancer growth in vivo but enhances its response to immunotherapy

Protein arginine methylation is a common post-translational modification (PTM) catalyzed by nine protein arginine methyltransferases (PRMTs). As the major symmetric arginine methyltransferase that methylates both histone and non-histone substrates, PRMT5 plays key roles in a number of biological processes critical for development and tumorigenesis. PRMT5 overexpression has been reported in multiple cancer types including prostate cancer (PCa), but the exact biological and mechanistic understanding of PRMT5 in aggressive PCa remains ill-defined. Here, we show that PRMT5 is upregulated in PCa, correlates with worse patient survival, promotes corrupted RNA splicing, and functionally cooperates with an array of pro-tumorigenic pathways to enhance oncogenesis. PRMT5 inhibition via either genetic knockdown or pharmacological inhibition reduces stemness with paralleled differentiation and arrests cell cycle progression without causing appreciable apoptosis. Strikingly, the severity of antitumor effect of PRMT5 inhibition correlates with disease aggressiveness, with AR+ PCa being less affected. Molecular characterization pinpoints MYC, but not (or at least to a lesser degree) AR, as the main partner of PRMT5 to form a positive feedback loop to exacerbate malignancy in both AR+ and AR— PCa cells. Inspired by the surprising finding that PRMT5 negatively correlates with tumor immune infiltration and transcriptionally suppresses an immune-gene program, we further show that although PRMT5 inhibitor (PRMT5i) EPZ015666 or anti-PD-1 immunotherapy alone exhibits limited antitumor effects, combination of PRMT5i with anti-PD-1 displays superior efficacy in inhibiting castration-resistant PCa (CRPC) in vivo. Finally, to expand the potential use of PRMT5i through a synthetic lethality concept, we also perform a global CRISPR/Cas9 knockout screen to unravel that many clinical-grade drugs of known oncogenic pathways can be repurposed to target CRPC when used in combination with PRMT5i at low doses. Collectively, our findings establish a rationale to exploit PRMT5i in combination with immunotherapy or other targeted therapies to treat aggressive PCa.

Novel strategies in HPV‑16‑related cervical cancer treatment: An in vitro study of combined siRNA-E5 with oxaliplatin and ifosfamide chemotherapy

BackgroundCervical cancer, primarily caused by HPV infection, remains a global health concern. Current treatments face challenges including drug resistance and toxicity. This study investigates combining E5-siRNA with chemotherapy drugs, Oxaliplatin and Ifosfamide, to enhance treatment efficacy in HPV-16 positive cervical cancer cells, targeting E5 oncoprotein to overcome limitations of existing therapies. MethodsThe CaSki cervical cancer cell line was transfected with E5-siRNA, and subsequently treated with Oxaliplatin/Ifosfamide. Quantitative real-time PCR was employed to assess the expression of related genes including p53, MMP2, Nanog, and Caspases. Cell apoptosis, cell cycle progression, and cell viability were evaluated using Annexin V/PI staining, DAPI staining, and MTT test, respectively. Furthermore, stemness ability was determined through a colony formation assay, and cell motility was assessed by wound healing assay. ResultsE5-siRNA transfection significantly reduced E5 mRNA expression in CaSki cells compared to the control group. The MTT assay revealed that monotherapy with E5-siRNA, Oxaliplatin, or Ifosfamide had moderate effects on cell viability. However, combination therapy showed synergistic effects, reducing the IC50 of Oxaliplatin from 11.42 × 10−8 M (45.36 μg/ml) to 6.71 × 10−8 M (26.66 μg/ml) and Ifosfamide from 12.52 × 10−5 M (32.7 μg/ml) to 8.206 × 10−5 M (21.43 μg/ml). Flow cytometry analysis demonstrated a significant increase in apoptosis for combination treatments, with apoptosis rates rising from 11.02 % (Oxaliplatin alone) and 16.98 % (Ifosfamide alone) to 24.8 % (Oxaliplatin + E5-siRNA) and 34.9 % (Ifosfamide + E5-siRNA). The sub-G1 cell population increased from 15.7 % (Oxaliplatin alone) and 18 % (Ifosfamide alone) to 21.9 % (Oxaliplatin + E5-siRNA) and 27.1 % (Ifosfamide + E5-siRNA), indicating cell cycle arrest. The colony formation assay revealed a substantial decrease in the number of colonies following combination treatment. qRT-PCR analysis showed decreased expression of stemness-related genes CD44 and Nanog, and migration-related genes MMP2 and CXCL8 in the combination groups. Apoptosis-related genes Casp-3, Casp-9, and pP53 showed increased expression following combination therapy, while BAX expression increased and BCL2 expression decreased relative to the control. ConclusionThe study demonstrates that combining E5-siRNA with Oxaliplatin or Ifosfamide enhances the efficacy of chemotherapy in HPV-16 positive cervical cancer cells. This synergistic approach effectively targets multiple aspects of cancer cell behavior, including proliferation, apoptosis, migration, and stemness. The findings suggest that this combination strategy could potentially allow for lower chemotherapy doses, thereby reducing toxicity while maintaining therapeutic efficacy. This research provides valuable insights into targeting HPV E5 as a complementary approach to existing therapies focused on E6 and E7 oncoproteins, opening new avenues for combination therapies in cervical cancer treatment.

Synergistic Roles of Non-Homologous End Joining and Homologous Recombination in Repair of Ionizing Radiation-Induced DNA Double Strand Breaks in Mouse Embryonic Stem Cells.

DNA double strand breaks (DSBs) are critical for the efficacy of radiotherapy as they lead to cell death if not repaired. DSBs caused by ionizing radiation (IR) initiate histone modifications and accumulate DNA repair proteins, including 53BP1, which forms distinct foci at damage sites and serves as a marker for DSBs. DSB repair primarily occurs through Non-Homologous End Joining (NHEJ) and Homologous Recombination (HR). NHEJ directly ligates DNA ends, employing proteins such as DNA-PKcs, while HR, involving proteins such as Rad54, uses a sister chromatid template for accurate repair and functions in the S and G2 phases of the cell cycle. Both pathways are crucial, as illustrated by the IR sensitivity in cells lacking DNA-PKcs or Rad54. We generated mouse embryonic stem (mES) cells which are knockout (KO) for DNA-PKcs and Rad54 to explore the combined role of HR and NHEJ in DSB repair. We found that cells lacking both DNA-PKcs and Rad54 are hypersensitive to X-ray radiation, coinciding with impaired 53BP1 focus resolution and a more persistent G2 phase cell cycle block. Additionally, mES cells deficient in DNA-PKcs or both DNA-PKcs and Rad54 exhibit an increased nuclear size approximately 18-24 h post-irradiation. To further explore the role of Rad54 in the absence of DNA-PKcs, we generated DNA-PKcs KO mES cells expressing GFP-tagged wild-type (WT) or ATPase-defective Rad54 to track the Rad54 foci over time post-irradiation. Cells lacking DNA-PKcs and expressing ATPase-defective Rad54 exhibited a similar phenotypic response to IR as those lacking both DNA-PKcs and Rad54. Despite a strong G2 phase arrest, live-cell imaging showed these cells eventually progress through mitosis, forming micronuclei. Additionally, mES cells lacking DNA-PKcs showed increased Rad54 foci over time post-irradiation, indicating an enhanced reliance on HR for DSB repair without DNA-PKcs. Our findings underscore the essential roles of HR and NHEJ in maintaining genomic stability post-IR in mES cells. The interplay between these pathways is crucial for effective DSB repair and cell cycle progression, highlighting potential targets for enhancing radiotherapy outcomes.

The Antitumour Mechanisms of Carotenoids: A Comprehensive Review.

Carotenoids, known for their antioxidant properties, have garnered significant attention for their potential antitumour activities. This comprehensive review aims to elucidate the diverse mechanisms by which carotenoids exert antitumour effects, focusing on both well-established and novel findings. We explore their role in inducing apoptosis, inhibiting cell cycle progression and preventing metastasis by affecting oncogenic and tumour suppressor proteins. The review also explores the pro-oxidant function of carotenoids within cancer cells. In fact, although their overall contribution to cellular antioxidant defences is well known and significant, some carotenoids can exhibit pro-oxidant effects under certain conditions and are able to elevate reactive oxygen species (ROS) levels in tumoural cells, triggering mitochondrial pathways that would lead to cell death. The final balance between their antioxidant and pro-oxidant activities depends on several factors, including the specific carotenoid, its concentration and the redox environment of the cell. Clinical trials are discussed, highlighting the conflicting results of carotenoids in cancer treatment and the importance of personalized approaches. Emerging research on rare carotenoids like bacterioruberin showcases their superior antioxidant capacity and selective cytotoxicity against aggressive cancer subtypes, such as triple-negative breast cancer. Future directions include innovative delivery systems, novel combinations and personalized treatments, aiming to enhance the therapeutic potential of carotenoids. This review highlights the promising yet complex landscape of carotenoid-based cancer therapies, calling for continued research and clinical exploration.

Targeted colorectal cancer treatment: In vitro anti-cancer effects of carnosine nanoparticles supported by agar and magnetic iron oxide

The usage of peptides in the colorectal cancer (CRC) treatment promises to be a new anti-cancer therapy with improved treatment efficacy. Carnosine, a natural dipeptide molecule, has been demonstrated to be a potential anti-cancer drug. Nonetheless, it shows an exhibition of high-water solubility and is quickly degraded by carnosinase. Meanwhile, agar and magnetic iron oxide are the most used materials for drug delivery due to some of their advantages such as the low cost and the larger biocompatibility feature. The purpose of this study was to investigate the anti-cancer ability of agar-encapsulated carnosine nanoparticles (AgCa-NPs) and agar-encapsulated carnosine nanoparticles-coated magnetic iron oxide nanoparticles (AgCaN-MNPs) in human CRC cells, HCT-116. We evaluated the effects of AgCa-NPs and AgCaN-MNPs with a variety of concentrations (0, 5, 10, 15, 30, 40, or 50 mM) on HCT-116 cells after 72 h and 96 h by using MTT assay and observation cell morphology. We then analyzed the cell cycle progression and assessed the expression changes of genes related to apoptosis, autophagy, necroptosis, and angiogenesis after treatment for 96 h. The results showed that AgCa-NPs and AgCaN-MNPs in vitro study decreased HCT-116 cells viability. This effect was attributed to arrest of cell cycle, induction of programmed cell death, and suppression of angiogenesis by AgCa-NPs and AgCaN-MNPs. These findings revealed the antitumor efficacy of AgCa-NPs or AgCaN-MNPs for CRC treatment.

Hepatocyte-derived tissue extracellular vesicles safeguard liver regeneration and support regenerative therapy

Tissue-derived extracellular vesicles (EVs) are emerging as pivotal players to maintain organ homeostasis, which show promise as a next-generation candidate for medical use with extensive source. However, the detailed function and therapeutic potential of tissue EVs remain insufficiently studied. Here, through bulk and single-cell RNA sequencing analyses combined with ultrastructural tissue examinations, we first reveal that in situ liver tissue EVs (LT-EVs) contribute to the intricate liver regenerative process after partial hepatectomy (PHx), and that hepatocytes are the primary source of tissue EVs in the regenerating liver. Nanoscale and proteomic profiling further identify that the hepatocyte-specific tissue EVs (Hep-EVs) are strengthened to release with carrying proliferative messages after PHx. Moreover, targeted inhibition of Hep-EV release via AAV-shRab27a in vivo confirms that Hep-EVs are required to orchestrate liver regeneration. Mechanistically, Hep-EVs from the regenerating liver reciprocally stimulate hepatocyte proliferation by promoting cell cycle progression through Cyclin-dependent kinase 1 (Cdk1) activity. Notably, supplementing with Hep-EVs from the regenerating liver demonstrates translational potential and ameliorates insufficient liver regeneration. This study provides a functional and mechanistic framework showing that the release of regenerative Hep-EVs governs rapid liver regeneration, thereby enriching our understanding of physiological and endogenous tissue EVs in organ regeneration and therapy.

PELO regulates erythroid differentiation through interaction with MYC to upregulate KLF10.

Erythropoiesis is a multistep process of erythroid cell production that is controlled by multiple regulatory factors. Ribosome rescue factor PELO plays a crucial role in cell meiotic division and mice embryonic development. However, the function of PELO in erythroid differentiation remains unclear. Here, we showed that knockdown of PELO increased hemin-induced erythroid differentiation of K562 and HEL cells, exhibiting a higher number of benzidine-positive cells and increased mRNA levels of erythroid genes. PELO knockdown inhibited the proliferation and cell cycle progression and promoted apoptosis of K562 cells. Mechanistically, PELO could regulate the expression of KLF10 through interaction with MYC. Moreover, KLF10 knockdown also enhanced erythroid differentiation of K562 and HEL cells induced by hemin. Collectively, our results demonstrated that PELO regulates erythroid differentiation and increases KLF10 expression levels by interacting with MYC.

GRK2-mediated AKT activation controls cell cycle progression and G2 checkpoint in a p53-dependent manner

Cell cycle checkpoints, activated by stressful events, halt the cell cycle progression, and prevent the transmission of damaged DNA. These checkpoints prompt cell repair but also trigger cell death if damage persists. Decision-making between these responses is multifactorial and context-dependent, with the tumor suppressor p53 playing a central role. In many tumor cells, p53 alterations lead to G1/S checkpoint loss and the weakening of the G2 checkpoint, rendering cell viability dependent on the strength of the latter through mechanisms not fully characterized. Cells with a strong pro-survival drive can evade cell death despite substantial DNA lesions. Deciphering the integration of survival pathways with p53-dependent and -independent mechanisms governing the G2/M transition is crucial for understanding G2 arrest functionality and predicting tumor cell response to chemotherapy. The serine/threonine kinase GRK2 emerges as a signaling node in cell cycle modulation. In cycling cells, but not in G2 checkpoint-arrested cells, GRK2 protein levels decline during G2/M transition through a process triggered by CDK2-dependent phosphorylation of GRK2 at the S670 residue and Mdm2 ubiquitination. We report now that this downmodulation in G2 prevents the unscheduled activation of the PI3K/AKT pathway, allowing cells to progress into mitosis. Conversely, higher GRK2 levels lead to tyrosine phosphorylation by the kinase c-Abl, promoting the direct association of GRK2 with the p85 regulatory subunit of PI3K and AKT activation in a GRK2 catalytic-independent manner. Hyperactivation of AKT is conditioned by p53’s scaffolding function, triggering FOXO3a phosphorylation, impaired Cyclin B1 accumulation, and CDK1 activation, causing a G2/M transition delay. Upon G2 checkpoint activation, GRK2 potentiates early arrest independently of p53 through AKT activation. However, its ability to overcome the G2 checkpoint in viable conditions depends on p53. Our results suggest that integrating the GRK2/PI3K/AKT axis with non-canonical functions of p53 might confer a survival advantage to tumor cells.

Exploiting WEE1 kinase activity as FUS::DDIT3-dependent therapeutic vulnerability in myxoid liposarcoma.

The pathognomonic FUS::DDIT3 fusion protein drives myxoid liposarcoma (MLS) tumorigenesis via aberrant transcriptional activation of oncogenic signaling. Since FUS::DDIT3 has so far not been pharmacologically tractable to selectively target MLS cells, this study investigated the functional role of the cell cycle regulator WEE1 as novel FUS::DDIT3‑dependent therapeutic vulnerability in MLS. Immunohistochemical evaluation of the cell cycle regulator WEE1 was performed in a large cohort of MLS specimens. FUS::DDIT3 dependency and biological function of the G1/S cell cycle checkpoint were analyzed in a mesenchymal stem cell model and liposarcoma cell lines in vitro. WEE1 activity was modulated by RNAi‑mediated knockdown and the small molecule inhibitor MK-1775 (Adavosertib). An established MLS cell line-based chicken chorioallantoic membrane model was employed for in vivo confirmation. We demonstrate that enhanced WEE1 pathway activity represents a hallmark of FUS::DDIT3‑expressing cell lines as well as MLS tissue specimens and that WEE1 is required for MLS cellular survival in vitro and in vivo. Pharmacologic inhibition of WEE1 activity results in DNA damage accumulation and cell cycle progression forcing cells to undergo apoptotic cell death. In addition, our results uncover FUS::DDIT3-dependent WEE1 expression as an oncogenic survival mechanism to tolerate high proliferation and resulting replication stress in MLS. Fusion protein-driven G1/S cell cycle checkpoint deregulation via overactive Cyclin E/CDK2 complexes thereby contributes to enhanced WEE1 inhibitor sensitivity in MLS. Our preclinical study identifies WEE1-mediated replication stress tolerance as molecular vulnerability in FUS::DDIT3-driven MLS tumorigenesis that could represent a novel target for therapeutic intervention.

The Regulation of SPRY4 Intronic Transcript 1 (SPRY4-IT1) on KIT Signaling and Imatinib Resistance of Gastrointestinal Stromal Tumor (GIST) Cells

BACKGROUND: SPRY4 intronic transcript 1 (SPRY4-IT1), is a long non-coding RNA coded by the intron of SPRY4. SPRY4 is highly expressed in gastrointestinal stromal tumor (GIST) and inhibits the tumorigenesis of GIST, but whether SPRY4-IT1 regulates the tumorigenesis of GIST or not remains unclear. Therefore, in this study, the regulation of SPRY4-IT1 expression and its role in GIST will be investigated.METHODS: GIST-T1 cells, and Ba/F3 cells which express KIT proto-oncogene (KIT) and SPRY4-IT1 were used as cell models. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was used to examine mRNA expression, while the protein expression and signal transduction were examined by western blot. The association between SPRY4-IT1 and KIT was examined by pull down of KIT and PCR. Cell proliferation, survival, and cell cycle progression were examined by cell counting kit-8 (CCK8) and flow cytometry.RESULTS: KIT mutants increased the expression of SPRY4-IT1 in GIST. SPRY4-IT1 bound to KIT, also enhanced the activation and expression of both wild-type KIT and primary KIT mutants, therefore increasing the activation of downstream signaling proteins AKT and ERK of KIT, GIST cell survival, and proliferation. In addition, SPRY4-IT1 reduced the sensitivity of wild-type KIT, or primary KIT mutants to the first-line targeted therapeutic drug of GIST, imatinib, which can inhibit KIT activation. Gaining drug-resistant secondary KIT mutants might be one of the main reasons of GIST recurrence after targeted therapy. Similar to wild-type KIT and primary KIT mutants, the activation and expression of secondary KIT mutants and their resistance to imatinib were also increased by SPRY4-IT1.CONCLUSION: The results indicated positive feedback between SPRY4-IT1 and wild-type KIT, primary KIT mutants or secondary KIT mutants, and the upregulation of AKT and ERK activation by SPRY4-IT1 in GIST cells, providing a new insight in the KIT signaling regulation in GIST, and the resistance of GIST to targeted therapy.KEYWORDS: SPRY4-IT1, KIT, GIST, SPRY4, signaling

Targeting NUF2 suppresses gastric cancer progression through G2/M phase arrest and apoptosis induction.

Gastric cancer (GC), a malignant tumor with poor prognosis, is one of the leading causes of cancer-related deaths worldwide; consequently, identifying novel therapeutic targets is crucial for its corresponding treatment. NUF2, a component of the NDC80 kinetochore complex, promotes cancer progression in multiple malignancies. Therefore, this study aimed to explore the potential of NUF2 as a therapeutic target to inhibit GC progression. Clinical samples from patients who underwent radical resection of GC at Lanzhou University Second Hospital from 2016 to 2021, cell count assays, colony formation assays, and cell-derived xenotransplantation (CDX) models were used to determine the effects of NUF2 on GC progression. Flow cytometry was used to detect the effect of NUF2 or quercetin on cell cycle progression and apoptosis. A live-cell time-lapse imaging assay was performed to determine the effect of NUF2 on the regulation of mitotic progression. Transcriptomics was used to investigate the NUF2-associated molecular mechanisms. Virtual docking and microscale thermophoresis were used to identify NUF2 inhibitors. Finally, CDX, organoid, and patient-derived xenograft (PDX) models were used to examine the efficacy of the NUF2 inhibitor in GC. NUF2 expression was significantly increased in GC and was negatively correlated with prognosis. The deletion of NUF2 suppressed GC progression both in vivo and in vitro. NUF2 significantly regulated the mitogen-activated protein kinase (MAPK) pathway, promoted G2/M phase transition, and inhibited apoptosis in GC cells. Additionally, quercetin was identified as a selective NUF2 inhibitor with low toxicity that significantly suppressed tumor growth in GC cells, organoids, CDX, and PDX models. Collectively, NUF2-mediated G2/M phase transition and apoptosis inhibition promoted GC progression; additionally, NUF2 inhibitors exhibited potent anti-GC activity. This study provides a new strategy for targeting NUF2 to suppress GC progression in clinical settings.