The p53 network: cellular and systemic DNA damage responses in cancer and aging

Da-Chai-Hu-Tang Formula inhibits the progression and metastasis in HepG2 cells through modulation of the PI3K/AKT/STAT3-induced cell cycle arrest and apoptosis

ETHNOPHARMACOLOGICAL RELEVANCE

Da-Chai-Hu-Tang (DCHT), a Chinese traditional herbal compound, has been utilized for the treatment of Hepatic diseases in China for over 1800 years. The DCHT formula contains eight herbals: Bupleurum chinense DC. (chaihu), Scutellaria baicalensis Georgi (huangqin), Paeonia lactiflora Pall. (baishao), Pinellia ternata (Thunb.) Makino (banxia), Rheum officinale Baill. (dahuang), Citrus × aurantium L. (zhishi), Zingiber officinale Roscoe (shengjiang), Ziziphus jujuba Mill. (dazao). Clinical studies have demonstrated the effectiveness of DCHT in hepatocellular carcinoma (HCC) and its ability to enhance the immunity of patients with hepatocellular carcinoma. A total of 20 Chinese articles have been published on the use of DCHT in treating HCC.

AIM OF THE STUDY

The study aimed to validate the effect of DCHT in HCC cells and to identify related targets (TP53, AKT1, BCL2, STAT3) in treating HCC by DCHT in vitro experiments.

MATERIALS AND METHODS

Cell proliferation and migration were investigated in vitro. Flow cytometry analysis was used to evaluate the cell cycle and apoptosis. Apoptotic bodies in HepG2 cells were observed using a confocal microscope. Biochemical detection was employed to analyze LDH release, MDA levels, and SOD levels. Bioinformatics analysis was used to predict core targets between DCHT and HCC, as well as potential signaling pathways. The protein levels of metastasis-associated, apoptosis, and PI3K, AKT, p-AKT, and STAT3 were further determined through Western blotting.

RESULTS

Following treatment with DCHT, the inhibition of viability, migration, and G2/M arrest was observed in HepG2 cells. Flow cytometry analysis and Morphological apoptosis studies provided evidence that DCHT could induce apoptosis in HepG2 cells. Biochemical detection revealed that DCHT could increase LDH release and the level of MDA, and inhibit the viability of the SOD. Bioinformatics analysis identified key targets such as TP53, AKT1, BCL2, STAT3. The PI3K/AKT/STAT3 signaling pathway emerged as a critical pathway in the KEGG enrichment analysis. Western blotting results indicated that DCHT could enhance the expression of E-cadherin, p53, and Bax, while reducing the content of N-cadherin, Bcl-2, PI3K, p-AKT, AKT1, and STAT3.

CONCLUSIONS

The results proved that DCHT could inhibit the progression and metastasis of HCC by regulating the expression of E-cadherin, N-cadherin, p53, Bax, Bcl-2, PI3K, p-AKT, AKT, and STAT3 through the PI3K/AKT/STAT3 signaling pathway.

DNA damage response-related signatures characterize the immune landscape and predict the prognosis of HCC via integrating single-cell and bulk RNA-sequencing

BACKGROUND

The occurrence and progression of hepatocellular carcinoma (HCC) are significantly affected by DNA damage response (DDR). Exploring DDR-related biomarkers can help predict the prognosis and immune characteristics of HCC.

METHODS

First, the single-cell RNA sequencing (scRNA-seq) dataset GSE242889 was processed and performed manual annotation. Then we found the marker genes of DDR-active subgroups based on "AUCell" algorithm. The "Limma" R package was used to identify differentially expressed genes (DEGs) between tumor and normal samples of HCC. The risk prognostic model was constructed by filtering genes using univariate Cox and LASSO regression analyses. Finally, the signatures were analyzed for immune infiltration, gene mutation, and drug sensitivity. Last but not least, KPNA2, which had the largest coefficient in our model was validated by experiments including western blot, MTT, colony formation and γ-H2AX assays.

RESULTS

We constructed a prognostic model based on 5 DDR marker genes including KIF2C, CDC20, KPNA2, UBE2S and ADH1B for HCC. We also proved that the model had an excellent performance in both training and validation cohorts. Patients in the high-risk group had a poorer prognosis, different immune features, gene mutation frequency, immunotherapy response and drug sensitivity compared with the low-risk group. Besides, our experimental results proved that KPNA2 was up-regulated in liver cancer cells than in hepatocytes. More importantly, the knockdown of KPNA2 significantly inhibited cell variability, proliferation and promoted DNA damage.

CONCLUSIONS

We innovatively integrated scRNA-seq and bulk RNA sequencing to construct the DDR-related prognostic model. Our model could effectively predict the prognosis, immune landscape and therapy response of HCC.

Lubricin-Inspired Nanozymes Reconstruct Cartilage Lubrication System with an "In-Out" Strategy

Lubricin, secreted primarily by chondrocytes, plays a critical role in maintaining the function of the cartilage lubrication system. However, both external factors such as friction and internal factors like oxidative stress can disrupt this system, leading to osteoarthritis. Inspired by lubricin, a lubricating nanozyme, that is, Poly-2-acrylamide-2-methylpropanesulfonic acid sodium salt-grafted aminofullerene, is developed to restore the cartilage lubrication system using an "In-Out" strategy. The "Out" aspect involves reducing friction through a combination of hydration lubrication and ball-bearing lubrication. Simultaneously, the "In" aspect aims to mitigate oxidative stress by reducing free radical, increasing autophagy, and improving the mitochondrial respiratory chain. This results in reduced chondrocyte senescence and increased lubricin production, enhancing the natural lubrication ability of cartilage. Transcriptome sequencing and Western blot results demonstrate that it enhances the functionality of mitochondrial respiratory chain complexes I, III, and V, thereby improving mitochondrial function in chondrocytes. In vitro and in vivo experiments show that the lubricating nanozymes reduce cartilage wear, improve chondrocyte senescence, and mitigate oxidative stress damage, thereby mitigating the progression of osteoarthritis. These findings provide novel insights into treating diseases associated with oxidative stress and frictional damage, such as osteoarthritis, and set the stage for future research and development of therapeutic interventions.

SIRT1 signaling pathways in sarcopenia: Novel mechanisms and potential therapeutic targets

Sarcopenia is an aging-related skeletal disease characterized by decreased muscle mass, strength, and physical function, severely affecting the quality of life (QoL) of the elderly population. Sirtuin 1 (SIRT1), as a nicotinamide adenine dinucleotide (NAD+)-dependent histone deacetylases, has been reported to participate in various aging-related signaling pathways and exert protective effect on many human diseases. SIRT1 functioned as an important role in the occurrence and progression of sarcopenia through regulating key pathways related to protein homeostasis, apoptosis, mitochondrial dysfunction, insulin resistance and autophagy in skeletal muscle, including SIRT1/Forkhead Box O (FoxO), AMP-activated protein kinase (AMPK)/SIRT1/nuclear factor κB (NF-κB), SIRT1/p53, AMPK/SIRT1/peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α), and SIRT1/live kinase B1 (LKB1)/AMPK pathways. However, the specific mechanisms of these processes have not been fully illuminated. Currently, several SIRT1-mediated interventions on sarcopenia have been preliminarily developed, such as SIRT1 activator polyphenolic compounds, exercising and calorie restriction. In this review, we summarized the predominant mechanisms of SIRT1 involved in sarcopenia and therapeutic modalities targeting the SIRT1 signaling pathways for the prevention and prognosis of sarcopenia.

A prominent role of LncRNA H19 in H. pylori CagA induced DNA damage response and cell malignancy

Helicobacter pylori (H. pylori), together with its CagA, has been implicated in causing DNA damage, cell cycle arrest, apoptosis, and the development of gastric cancer. Although lncRNA H19 is abundantly expressed in gastric cancer and functions as a pro-oncogene, it remains unclear whether lncRNA H19 contributes to the oncogenic process of H. pylori CagA. This study investigates the role of H19 in the DNA damage response and malignancy induced by H. pylori. It was observed that cells infected with CagA+ H. pylori strain (GZ7/cagA) showed significantly higher H19 expression, resulting in increased γH2A.X and p-ATM expression and decreased p53 and Rad51 expression. Faster cell migration and invasion was also observed, which was reversed by H19 knockdown in H. pylori. YWHAZ was identified as an H19 target protein, and its expression was increased in H19 knockdown cells. GZ7/cagA infection responded to the increased YWHAZ expression induced by H19 knockdown. In addition, H19 knockdown stimulated cells to enter the G2-phase and attenuated the effect of GZ7/cagA infection on the cellular S-phase barrier. The results suggest that H. pylori CagA can upregulate H19 expression, participate in the DNA damage response and promote cell migration and invasion, and possibly affect cell cycle arrest via regulation of YWHAZ.

Phenethyl isothiocyanate inhibits the carcinogenic properties of hepatocellular carcinoma Huh7.5.1 cells by activating MAPK/PI3K-Akt/p53 signaling pathways

Background

Hepatocellular carcinoma (HCC) is an aggressive malignancy with limited effective treatment options. Phenethyl isothiocyanate (PEITC) is a bioactive substance present primarily in the cruciferous vegetables. PEITC has exhibited anti-cancer properties in various cancers, including lung, bile duct, and prostate cancers. It has been demonstrated that PEITC can inhibit the proliferation, invasion, and metastasis of SK-Hep1 cells, while effectively inducing apoptosis and cell cycle arrest in HepG2 cells. However, knowledge of its anti-carcinogenic effects on Huh7.5.1 cells and its underlying mechanism remains elusive. In the present study, we aim to evaluate the anti-carcinogenic effects of PEITC on human HCC Huh7.5.1 cells.

Methods

MTT assay and colony formation assay was performed to investigate the anti-proliferative effects of PEITC against Huh7.5.1 cells. The pro-apoptosis effects of PEITC were determined by Annexin V-FITC/PI double staining assay by flow cytometry (FCM), mitochondrial transmembrane potential (MMP) measurement, and Caspase-3 activity detection. A DAPI staining and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay was conducted to estimate the DNA damage in Huh7.5.1 cells induced by PEITC. Cell cycle progression was determined by FCM. Transwell invasion assay and wound healing migration assay were performed to investigate the impact of PEITC on the migration and invasion of Huh7.5.1 cells. In addition, transcriptome sequencing and gene set enrichment analysis (GSEA) were used to explore the potential molecular mechanisms of the inhibitory effects of PEITC on HCC. Quantitative real-time PCR (qRT-PCR) analysis was performed to verify the transcriptome data.

Results

MTT assay showed that treatment of Huh7.5.1 cells with PEITC resulted in a dose-dependent decrease in viability, and colony formation assay further confirmed its anti-proliferative effect. Furthermore, we found that PEITC could induce mitochondrial-related apoptotic responses, including a decrease of mitochondrial transmembrane potential, activation of Caspase-3 activity, and generation of intracellular reactive oxygen species. It was also observed that PEITC caused DNA damage and cell cycle arrest in the S-phase in Huh7.5.1 cells. In addition, the inhibitory effect of PEITC on the migration and invasion ability of Huh7.5.1 cells was assessed. Transcriptome sequencing analysis further suggested that PEITC could activate the typical MAPK, PI3K-Akt, and p53 signaling pathways, revealing the potential mechanism of PEITC in inhibiting the carcinogenic properties of Huh7.5.1 cells.

Conclusion

PEITC exhibits anti-carcinogenic activities against human HCC Huh7.5.1 cells by activating MAPK/PI3K-Akt/p53 signaling pathways. Our results suggest that PEITC may be useful for the anti-HCC treatment.

Apoptosis in post-streptococcal glomerulonephritis and mechanisms for failed of inflammation resolution

Post-streptococcal glomerulonephritis is a condition resulting from infection by group A beta-hemolytic streptococcus. The main mechanism involves the formation of immune complexes formed in the circulation or in situ on the glomerular basement membrane, which activates complement and causes various inflammatory processes. Cellular mechanisms have been reported in the induction of kidney damage represented by the infiltration of innate cells (neutrophils and monocyte/macrophages) and adaptive cells (CD4 + lymphocytes and CD8 + lymphocytes) of the immune system. These cells induce kidney damage through various mechanisms. It has been reported that nephritogenic antigens are capable of inducing inflammatory processes early, even before the formation of immune complexes. Usually, this disease progresses towards clinical and renal normalization; however, in a smaller number of patients, it evolves into chronicity and persistent kidney damage. Hypotheses have been proposed regarding the mechanisms underlying this progression to chronicity including failure to induce apoptosis and failure to phagocytose apoptotic cells, allowing these cells to undergo membrane permeabilization and release pro-inflammatory molecules into the environment, thereby perpetuating renal inflammation. Other mechanisms involved include persistent infection, genetic background of the host's complement system, tubulointerstitial changes, and pre-existing kidney damage due to old age and comorbidities.

Targeting tumor suppressor p53 for organ fibrosis therapy

Fibrosis is a reparative and progressive process characterized by abnormal extracellular matrix deposition, contributing to organ dysfunction in chronic diseases. The tumor suppressor p53 (p53), known for its regulatory roles in cell proliferation, apoptosis, aging, and metabolism across diverse tissues, appears to play a pivotal role in aggravating biological processes such as epithelial-mesenchymal transition (EMT), cell apoptosis, and cell senescence. These processes are closely intertwined with the pathogenesis of fibrotic disease. In this review, we briefly introduce the background and specific mechanism of p53, investigate the pathogenesis of fibrosis, and further discuss p53's relationship and role in fibrosis affecting the kidney, liver, lung, and heart. In summary, targeting p53 represents a promising and innovative therapeutic approach for the prevention and treatment of organ fibrosis.

Gemfibrozil-Platinum(IV) Precursors for New Enhanced-Starvation and Chemotherapy In Vitro and In Vivo

A brand-new enhanced starvation is put forward to trigger sensitized chemotherapy: blocking tumor-relation blood vessel formation and accelerating nutrient degradation and efflux. Following this concept, two cisplatin-like gemfibrozil-derived Pt(IV) prodrugs, GP and GPG, are synthesized. GP and GPG had nanomolar IC50 against A2780 cells and higher selectivity against normal cells than cisplatin. Bioactivity results confirmed that GP and GPG highly accumulated in cells and induced DNA damage, G2-phase arrest, and p53 expression. Besides, they could increase ROS and MDA levels and reduce mitochondrial membrane potential and Bcl-2 expression to promote cell apoptosis. In vivo, GP showed superior antitumor activity in A2780 tumor-bearing mice with no observable tissue damage. Mechanistic studies suggested that highly selective chemotherapy could be due to the new enhanced starvation effect: blocking vasculature formation via inhibiting the CYP2C8/EETs pathway and VEGFR2, NF-κB, and COX-2 expression and cholesterol efflux and degradation acceleration via increasing ABCA1 and PPARα.

Research on the toxicological prognostic significance of age-related genes in endometrial cancer unveiling key factors in patient prognosis

This study investigates the influence of aging-related genes on endometrial cancer, a prominent gynecological malignancy with rising incidence and mortality. By analyzing gene expression differences between cancerous and normal endometrial tissues, 42 aging-related genes were identified as differentially expressed. Utilizing the TCGA-UCEC sample, consensus clustering divided the samples into two molecular subgroups, Aging low and Aging high, based on their expression profiles. These subgroups showed distinct prognoses and survival rates, with the Aging high group associated with DNA repair and cell cycle pathways, and the Aging low group showing suppressed metabolic pathways and increased immune cell infiltration, suggesting a potential for better immunotherapy outcomes. Mutation analysis did not find significant differences in mutation frequencies between the groups, but a high Tumor Mutation Burden (TMB) correlated with better prognosis. A risk score model was also developed, showcasing significant prognostic power. Further analysis of the SIX1 gene revealed its overexpression in cancer cells. Drug sensitivity tests indicated that the low-risk group might respond better to chemotherapy. This research underscores the significance of aging-related genes in endometrial cancer, offering insights into their prognostic value and therapeutic potential, which could lead to personalized treatment approaches and enhanced patient management.

B-Myb deficiency boosts bortezomib-induced immunogenic cell death in colorectal cancer

B-Myb has received considerable attention for its critical tumorigenic function of supporting DNA repair. However, its modulatory effects on chemotherapy and immunotherapy have rarely been reported in colorectal cancer. Bortezomib (BTZ) is a novel compound with chemotherapeutic and immunotherapeutic effects, but it fails to work in colorectal cancer with high B-Myb expression. The present study was designed to investigate whether B-Myb deletion in colorectal cancer could potentiate the immune efficacy of BTZ against colorectal cancer and to clarify the underlying mechanism. Stable B-Myb knockdown was induced in colorectal cancer cells, which increased apoptosis of the cancer cells relative to the control group in vitro and in vivo. We found that BTZ exhibited more favourable efficacy in B-Myb-defective colorectal cancer cells and tumor-bearing mice. BTZ treatment led to differential expression of genes enriched in the p53 signaling pathway promoted more powerful downstream DNA damage, and arrested cell cycle in B-Myb-defective colorectal cancer. In contrast, recovery of B-Myb in B-Myb-defective colorectal cancer cells abated BTZ-related DNA damage, cell cycle arrest, and anticancer efficacy. Moreover, BTZ promoted DNA damage-associated enhancement of immunogenicity, as indicated by potentiated expression of HMGB1 and HSP90 in B-Myb-defective cells, thereby driving M1 polarization of macrophages. Collectively, B-Myb deletion in colorectal cancer facilitates the immunogenic death of cancer cells, thereby further promoting the immune efficacy of BTZ by amplifying DNA damage. The present work provides an effective molecular target for colorectal cancer immunotherapy with BTZ.

Conserved methylation signatures associate with the tumor immune microenvironment and immunotherapy response

BACKGROUND

Aberrant DNA methylation is a major characteristic of cancer genomes. It remains unclear which biological processes determine epigenetic reprogramming and how these processes influence the variants in the cancer methylome, which can further impact cancer phenotypes.

METHODS

We performed pairwise permutations of 381,900 loci in 569 paired DNA methylation profiles of cancer tissue and matched normal tissue from The Cancer Genome Atlas (TCGA) and defined conserved differentially methylated positions (DMPs) based on the resulting null distribution. Then, we derived independent methylation signatures from 2,465 cancer-only methylation profiles from the TCGA and 241 cell line-based methylation profiles from the Genomics of Drug Sensitivity in Cancer (GDSC) cohort using nonnegative matrix factorization (NMF). We correlated DNA methylation signatures with various clinical and biological features, including age, survival, cancer stage, tumor immune microenvironment factors, and immunotherapy response. We inferred the determinant genes of these methylation signatures by integrating genomic and transcriptomic data and evaluated the impact of these signatures on cancer phenotypes in independent bulk and single-cell RNA/methylome cohorts.

RESULTS

We identified 7,364 differentially methylated positions (2,969 Hyper-DMPs and 4,395 Hypo-DMPs) in nine cancer types from the TCGA. We subsequently retrieved three highly conserved, independent methylation signatures (Hyper-MS1, Hypo-MS1, and Hypo-MS4) from cancer tissues and cell lines based on these Hyper and Hypo-DMPs. Our data suggested that Hypo-MS4 activity predicts poor survival and is associated with immunotherapy response and distant tumor metastasis, and Hypo-MS4 activity is related to TP53 mutation and FOXA1 binding specificity. In addition, we demonstrated a correlation between the activities of Hypo-MS4 in cancer cells and the fractions of regulatory CD4 + T cells with the expression levels of immunological genes in the tumor immune microenvironment.

CONCLUSIONS

Our findings demonstrated that the methylation signatures of distinct biological processes are associated with immune activity in the cancer microenvironment and predict immunotherapy response.

Molecular engineering of AIE-active boron clustoluminogens for enhanced boron neutron capture therapy

The development of boron delivery agents bearing an imaging capability is crucial for boron neutron capture therapy (BNCT), yet it has been rarely explored. Here we present a new type of boron delivery agent that integrates aggregation-induced emission (AIE)-active imaging and a carborane cluster for the first time. In doing so, the new boron delivery agents have been rationally designed by incorporating a high boron content unit of a carborane cluster, an erlotinib targeting unit towards lung cancer cells, and a donor-acceptor type AIE unit bearing naphthalimide. The new boron delivery agents demonstrate both excellent AIE properties for imaging purposes and highly selective accumulation in tumors. For example, at a boron delivery agent dose of 15 mg kg-1, the boron amount reaches over 20 μg g-1, and both tumor/blood (T/B) and tumor/normal cell (T/N) ratios reach 20-30 times higher than those required by BNCT. The neutron irradiation experiments demonstrate highly efficient tumor growth suppression without any observable physical tissue damage and abnormal behavior in vivo. This study not only expands the application scopes of both AIE-active molecules and boron clusters, but also provides a new molecular engineering strategy for a deep-penetrating cancer therapeutic protocol based on BNCT.

GINS2 regulates temozolomide chemosensitivity via the EGR1/ECT2 axis in gliomas

Temozolomide (TMZ), a DNA alkylating agent, has become the primary treatment for glioma, the most common malignancy of the central nervous system. Although TMZ-containing regimens produce significant clinical response rates, some patients inevitably suffer from inferior treatment outcomes or disease relapse, likely because of poor chemosensitivity of glioma cells due to a robust DNA damage response (DDR). GINS2, a subunit of DNA helicase, contributes to maintaining genomic stability and is highly expressed in various cancers, promoting their development. Here, we report that GINS2 was upregulated in TMZ-treated glioma cells and co-localized with γH2AX, indicating its participation in TMZ-induced DDR. Furthermore, GINS2 regulated the malignant phenotype and TMZ sensitivity of glioma cells, mostly by promoting DNA damage repair by affecting the mRNA stability of early growth response factor 1 (EGR1), which in turn regulates the transcription of epithelial cell-transforming sequence 2 (ECT2). We constructed a GINS2-EGR1-ECT2 prognostic model, which accurately predicted patient survival. Further, we screened Palbociclib/BIX-02189 which dampens GINS2 expression and synergistically inhibits glioma cell proliferation with TMZ. These findings delineate a novel mechanism by which GINS2 regulates the TMZ sensitivity of glioma cells and propose a promising combination therapy to treat glioma.

PR55α-controlled protein phosphatase 2A inhibits p16 expression and blocks cellular senescence induction by γ-irradiation

Cellular senescence is a permanent cell cycle arrest that can be triggered by both internal and external genotoxic stressors, such as telomere dysfunction and DNA damage. The execution of senescence is mainly by two pathways, p16/RB and p53/p21, which lead to CDK4/6 inhibition and RB activation to block cell cycle progression. While the regulation of p53/p21 signaling in response to DNA damage and other insults is well-defined, the regulation of the p16/RB pathway in response to various stressors remains poorly understood. Here, we report a novel function of PR55α, a regulatory subunit of PP2A Ser/Thr phosphatase, as a potent inhibitor of p16 expression and senescence induction by ionizing radiation (IR), such as γ-rays. The results show that ectopic PR55α expression in normal pancreatic cells inhibits p16 transcription, increases RB phosphorylation, and blocks IR-induced senescence. Conversely, PR55α-knockdown by shRNA in pancreatic cancer cells elevates p16 transcription, reduces RB phosphorylation, and triggers senescence induction after IR. Furthermore, this PR55α function in the regulation of p16 and senescence is p53-independent because it was unaffected by the mutational status of p53. Moreover, PR55α only affects p16 expression but not p14 (ARF) expression, which is also transcribed from the same CDKN2A locus but from an alternative promoter. In normal human tissues, levels of p16 and PR55α proteins were inversely correlated and mutually exclusive. Collectively, these results describe a novel function of PR55α/PP2A in blocking p16/RB signaling and IR-induced cellular senescence.

The Role of Oxidative Stress in Tumorigenesis and Progression

Oxidative stress refers to the imbalance between the production of reactive oxygen species (ROS) and the endogenous antioxidant defense system. Its involvement in cell senescence, apoptosis, and series diseases has been demonstrated. Advances in carcinogenic research have revealed oxidative stress as a pivotal pathophysiological pathway in tumorigenesis and to be involved in lung cancer, glioma, hepatocellular carcinoma, leukemia, and so on. This review combs the effects of oxidative stress on tumorigenesis on each phase and cell fate determination, and three features are discussed. Oxidative stress takes part in the processes ranging from tumorigenesis to tumor death via series pathways and processes like mitochondrial stress, endoplasmic reticulum stress, and ferroptosis. It can affect cell fate by engaging in the complex relationships between senescence, death, and cancer. The influence of oxidative stress on tumorigenesis and progression is a multi-stage interlaced process that includes two aspects of promotion and inhibition, with mitochondria as the core of regulation. A deeper and more comprehensive understanding of the effects of oxidative stress on tumorigenesis is conducive to exploring more tumor therapies.

Mutational landscape of TP53 and CDH1 in gastric cancer

In this editorial we comment on an article published in a recent issue of the World J Gastrointest Surg. A common gene mutation in gastric cancer (GC) is the TP53 mutation. As a tumor suppressor gene, TP53 is implicated in more than half of all tumor occurrences. TP53 gene mutations in GC tissue may be related with clinical pathological aspects. The TP53 mutation arose late in the progression of GC and aided in the final switch to malignancy. CDH1 encodes E-cadherin, which is involved in cell-to-cell adhesion, epithelial structure maintenance, cell polarity, differentiation, and intracellular signaling pathway modulation. CDH1 mutations and functional loss can result in diffuse GC, and CDH1 mutations can serve as independent prognostic indicators for poor prognosis. GC patients can benefit from genetic counseling and testing for CDH1 mutations. Demethylation therapy may assist to postpone the onset and progression of GC. The investigation of TP53 and CDH1 gene mutations in GC allows for the investigation of the relationship between these two gene mutations, as well as providing some basis for evaluating the prognosis of GC patients.

The CDK4/6 Inhibitor Palbociclib Induces Cell Senescence of High-grade Serous Ovarian Cancer Through Acetylation of p53

Cell senescence is an anti-cancer strategy following DNA repair and apoptosis, which is associated with the initiation, progression, and treatment of ovarian cancer. The CDK4/6 inhibitor alters cell cycle and induces cell senescence dependent on retinoblastoma (RB) family proteins. Objective Herein, we aimed to explore the effects of Palbociclib (a CDK4/6 inhibitor) on cellular senescence of high-grade serous ovarian cancer (HGSOC). Cell viability and cell cycle were evaluated by cell counting kit-8 and flow cytometry. Cell senescence was analyzed using the SA-β-gal staining assay. The senescence-associated secretory phenotype was assessed using quantitative PCR (qPCR). Senescence-related markers were tested using western blot. The role of Palbociclib in vivo was clarified using xenograft tumor. Acetylation of p53 was evaluated by qPCR and western blot. The results showed that Palbociclib inhibited cell viability, blocked cell cycle at G0/G1 phase, and induced cell senescence. A rescue study indicated that knockdown of p53 reversed the effects on cell cycle and senescence induced by Palbociclib. Moreover, we found that Palbociclib promotes P300-mediated p53 acetylation, thus increasing p53 stability and transcription activity. Moreover, Palbociclib suppressed tumor growth in vivo with increased p53 and acetylated p53 levels. In conclusion, Palbociclib induced cell senescence of HGSOC through P300-mediated p53 acetylation, suggesting that Palbociclib may have the effect of treating HGSOC.

The impact of oleuropein on miRNAs regulating cell death signaling pathway in human cervical cancer cells

Cervical cancer is known as the second most pervasive malignancy in women across the globe. The role played by microRNAs (miRNAs) in the initiation, progression, and metastasis of this cancer has received specific attention. The use of natural compounds leading cancer cells toward apoptosis is a feasible strategy for cancer therapy. Oleuropein, an olive-extracted phenolic substance, displays anticancer properties. Here, it was attempted to assess the role played by oleuropein in cell viability in cervical cancer and changes in the expression of some miRNAs associated with cervical cancer as well as some of their possible target genes selected using bioinformatics analysis. For this purpose, HeLa cell line was exposed to several oleuropein concentrations for 48 and 72 h. After that, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay and flow cytometry were employed to assess cell viability and apoptosis, respectively. In addition, to conduct bioinformatics analysis, Cytoscape computer program was used based on STRING database. Furthermore, to examine the role played by oleuropein in the expression of miRNAs of interest as well as their potential target genes, real-time PCR was employed. The findings indicated that oleuropein reduced cell viability through inducing apoptosis. As a result of treatment with oleuropein, miR-34a, miR-125b, and miR-29a showed increased expression levels, whereas miR-181b, miR-221, and miR-16 showed decreased expression levels. Furthermore, oleuropein reduced the expression of the anti-apoptotic genes Bcl-2 and Mcl1, whereas it elevated the expression of the pro-apoptotic Bid, Fas, and TNFRSF10B genes and the p53 tumor suppressor. Our results indicate that the apoptosis induction is a mechanism of action of oleuropein in HeLa cells. Because of its effect on the reflation of the expression of genes and miRNAs effective in the pathogenesis of cervical cancer, oleuropein shows potential as an effective research tool for developing new natural drugs for treating cervical cancer.

Theaflavin pretreatment ameliorates renal ischemia/reperfusion injury by attenuating apoptosis and oxidative stress in vivo and in vitro

Oxidative stress-induced apoptosis is an important pathological process in renal ischemia/reperfusion injury (RIRI). Theaflavin (TF) is the main active pigment and polyphenol in black tea. It has been widely reported because of its biological activity that can reduce oxidative stress and protect against many diseases. Here, we explored the role of theaflavin in the pathological process of RIRI. In the present study, the RIRI model of 45 min ischemia and 24 h reperfusion was established in C57BL/6 J male mice, and theaflavin was used as an intervention. Compared with the RIRI group, the renal filtration function, renal tissue damage and antioxidant capacity of the theaflavin intervention group were significantly improved, while the level of apoptosis was reduced. TCMK-1 cells were incubated under hypoxia for 48 h and then reoxygenated for 6 h to simulate RIRI in vitro. The application of theaflavin significantly promoted the translocation of p53 from cytoplasm to nucleus, upregulated the expression of glutathione peroxidase 1 (GPx-1) in cells, and inhibited oxidative stress damage and apoptosis. Transfection with p53 siRNA can partially inhibit the effect of theaflavin. Thus, theaflavin exerted a protective effect against RIRI by inhibiting apoptosis and oxidative stress via regulating the p53/GPx-1 pathway. We conclude that theaflavin has the potential to become a candidate drug for the prevention and treatment of RIRI.

RAD54B inhibits vascular endothelial senescence via suppression of CHK1/p53/p21 pathway

RAD54B belongs to the SNF2/SWI2 superfamily, participating in homologous recombination repair. DNA damage is the central driver of aging, but there is no direct evidence of an association between RAD54B and vascular aging. The present study sought to investigate the role and mechanisms of RAD54B in endothelial senescence. In senescent animal models, including spontaneously hypertensive rats, normal aging mice, and D-gal-induced senescent mice, and senescent cell models induced by H2O2, D-gal, and culture, RAD54B was remarkably downregulated. Knockdown of RAD54B increased the expression of p53 and p21, increased the ratio of SA-β-gal-positive cells, and decreased the proportion of EdU-positive cells. Conversely, overexpression of RAD54B reversed the senescent phenotypes stimulated by H2O2 and delayed replicative endothelial senescence. Mechanistically, silencing RAD54B compensatorily increased the expression of RAD51/XRCC4, which remained unchanged in H2O2-induced senescence. RAD54B lacking the SNF2 domain could still reverse the increasing expression of p53/p21 induced by H2O2. RAD54B reduced γH2A.X expression and inhibited the expression and phosphorylation of CHK1. In conclusion, RAD54B exerts a direct protective effect against DNA damage through enhancing homologous recombination repair in endothelial senescence, resulting in inhibition of the downstream CHK1/p53/p21 pathway, suggesting that RAD54B may be a potential therapeutic target for vascular aging-associated diseases.

KRAS is a molecular determinant of platinum responsiveness in glioblastoma

BACKGROUND

KRAS is the undisputed champion of oncogenes, and despite its prominent role in oncogenesis as mutated gene, KRAS mutation appears infrequent in gliomas. Nevertheless, gliomas are considered KRAS-driven cancers due to its essential role in mouse malignant gliomagenesis. Glioblastoma is the most lethal primary brain tumor, often associated with disturbed RAS signaling. For newly diagnosed GBM, the current standard therapy is alkylating agent chemotherapy combined with radiotherapy. Cisplatin is one of the most effective anticancer drugs and is used as a first-line treatment for a wide spectrum of solid tumors (including medulloblastoma and neuroblastoma) and many studies are currently focused on new delivery modalities of effective cisplatin in glioblastoma. Its mechanism of action is mainly based on DNA damage, inducing the formation of DNA adducts, triggering a series of signal-transduction pathways, leading to cell-cycle arrest, DNA repair and apoptosis.

METHODS

Long-term cultures of human glioblastoma, U87MG and U251MG, were either treated with cis-diamminedichloroplatinum (cisplatin, CDDP) and/or MEK-inhibitor PD98059. Cytotoxic responses were assessed by cell viability (MTT), protein expression (Western Blot), cell cycle (PI staining) and apoptosis (TUNEL) assays. Further, gain-of-function experiments were performed with cells over-expressing mutated hypervariable region (HVR) KRASG12V plasmids.

RESULTS

Here, we studied platinum-based chemosensitivity of long-term cultures of human glioblastoma from the perspective of KRAS expression, by using CDDP and MEK-inhibitor. Endogenous high KRAS expression was assessed at transcriptional (qPCR) and translational levels (WB) in a panel of primary and long-term glioblastoma cultures. Firstly, we measured immediate cellular adjustment through direct regulation of protein concentration of K-Ras4B in response to cisplatin treatment. We found increased endogenous protein abundance and involvement of the effector pathway RAF/MEK/ERK mitogen-activated protein kinase (MAPK) cascade. Moreover, as many MEK inhibitors are currently being clinically evaluated for the treatment of high-grade glioma, so we concomitantly tested the effect of the potent and selective non-ATP-competitive MEK1/2 inhibitor (PD98059) on cisplatin-induced chemosensitivity in these cells. Cell-cycle phase distribution was examined using flow cytometry showing a significant cell-cycle arrest in both cultures at different percentage, which is modulated by MEK inhibition. Cisplatin-induced cytotoxicity increased sub-G1 percentage and modulates G2/M checkpoint regulators cyclins D1 and A. Moreover, ectopic expression of a constitutively active KRASG12V rescued CDDP-induced apoptosis and different HVR point mutations (particularly Ala 185) reverted this phenotype.

CONCLUSION

These findings warrant further studies of clinical applications of MEK1/2 inhibitors and KRAS as 'actionable target' of cisplatin-based chemotherapy for glioblastoma.

Anti-aging formula protects skin from oxidative stress-induced senescence through the inhibition of CXCR2 expression

ETHNOPHARMACOLOGICAL RELEVANCE

The skin is affected by endogenous and exogenous factors, which are the intuitive consequence expression of aging. Aging not only affects the aesthetics of the skin but also causes the decline of skin functions, leading to many skin diseases and even skin cancer. Anti-aging formula (AAF) has various biological effects such as antioxidants, regulation of intestinal flora metabolism, anti-aging, and memory improvement. However, it is not clarified whether it could be anti-aging of the skin and the anti-aging mechanism.

AIM OF THE STUDY

This study aimed to investigate whether AAF could prevent skin from oxidative stress-induced senescence and explore the underlying molecular mechanisms.

MATERIALS AND METHODS

A mouse skin oxidative stress aging model was established based on ultraviolet (UV) irradiation, and parameters such as skin water content, melanogenesis, wrinkle production, pathological changes, and aging marker proteins were measured to elucidate whether AAF has an anti-aging effect on the skin. Subsequently, transcriptome sequencing (RNA-Seq) was used to identify target genes. An in vitro cellular senescence model was established to assess the role of AAF against cellular oxidative stress senescence by detecting senescence-related markers, while the specific mechanism of action of AAF in delaying skin senescence was elucidated by silencing or overexpression of targets.

RESULTS

In vivo experiments demonstrated that AAF significantly increased skin water content, reduced skin sensitivity and melanin content, slowed wrinkles, improved UV-induced epidermal thickening, increased collagen fiber content, improved elastic fiber morphology, and reduced the expression of senescence proteins P21 and P16 in skin tissues. The RNA-Seq results identified chemokine receptor 2 (CXCR2) as one of the potential targets for delaying skin senescence. In vitro experiments showed that AAF markedly improved the aging phenotype, and knockdown or overexpression experiments verified the essential role of CXCR2 in the skin senescence process. Mechanistic studies suggested that AAF inhibited the P38/P53 pathway by reducing CXCR2 expression, which improved the aging phenotype, reduced oxidative damage, and ultimately delayed cellular senescence.

CONCLUSION

The results reveal that AAF protects skin from oxidative stress-induced senescence by regulating the expression of critical target CXCR2, reducing P38 protein phosphorylation, and inhibiting P53 pathway activation. These discoveries implicate the potential of AAF in the protection of skin aging disease.

KIF20B Correlates with LUAD Progression and Is an Independent Risk Factor

OBJECTIVE

Kinesin family proteins (KIFs) play crucial roles in human tumorigenesis and progression. This study aimed to investigate the expression and association of Kinesin family member 20B (KIF20B) with lung adenocarcinoma (LUAD).

METHODS

RNA-seq data from LUAD patients (n = 535) were extracted from TCGA. KIF20B expression was compared between tumor tissues and controls, and between different stages of the disease. Survival and Cox regression analyses were performed, as well as in vitro cellular experiments on A549 cells.

RESULTS

KIF20B is upregulated in LUAD tumor tissues compared with controls and is higher in advanced stages. Patients with high expression of KIF20B have shorter survival times. KIF20B is an independent risk factor for the prognosis of LUAD. High KIF20B expression samples were enriched in signaling pathways related to tumor progression. si-KIF20B transfection reduced migration and invasion of A549 cells and increased apoptosis. The expression of p53 and Bax proteins was upregulated by si-KIF20B, while Bcl-2 was down-regulated.

DISCUSSION

This study reveals that high KIF20B expression is an independent risk factor for the poor prognosis of LUAD. The inhibition of KIF20B might be of great value for suppressing LUAD progression.

Transactivation by partial function P53 family mutants is increased by the presence of G-quadruplexes at a promoter site

The effect of mutations in the P53 family of transcription factors on their biological functions, including partial or complete loss of transcriptional activity, has been confirmed several times. At present, P53 family proteins showing partial loss of activity appear to be promising potential candidates for the development of novel therapeutic strategies which could restore their transcriptional activity. In this context, it is important to employ tools to precisely monitor their activity; in relation to this, non-canonical DNA secondary structures in promoters including G-quadruplexes (G4s) were shown to influence the activity of transcription factors. Here, we used a defined yeast assay to evaluate the impact of differently modeled G4 forming sequences on a panel of partial function P53 family mutant proteins. Specifically, a 22-mer G4 prone sequence (derived from the KSHV virus) and five derivatives that progressively mutate characteristic guanine stretches were placed upstream of a minimal promoter, adjacent to a P53 response element in otherwise isogenic yeast luciferase reporter strains. The transactivation ability of cancer-associated P53 (TA-P53α: A161T, R213L, N235S, V272L, R282W, R283C, R337C, R337H, and G360V) or Ectodermal Dyplasia syndromes-related P63 mutant proteins (ΔN-P63α: G134D, G134V and inR155) were tested. Our results show that the presence of G4 forming sequences can increase the transactivation ability of partial function P53 family proteins. These observations are pointing to the importance of DNA structural characteristics for accurate classification of P53 family proteins functionality in the context of the wide variety of TP53 and TP63 germline and somatic mutations.

miR-460b-5p promotes proliferation and differentiation of chicken myoblasts and targets RBM19 gene

The meat production of broilers is crucial to economic benefits of broiler industries, while the slaughter performance of broilers is directly determined by skeletal muscle development. Hence, the broiler breeding for growth traits shows a great importance. As a kind of small noncoding RNA, microRNA (miRNA) can regulate the expression of multiple genes and perform a wide range of regulation in organisms. Currently, more and more studies have confirmed that miRNAs are closely associated with skeletal muscle development of chickens. Based on our previous miR-seq analysis (accession number: PRJNA668199), miR-460b-5p was screened as one of the key miRNAs probably involved in the growth regulation of chickens. However, the regulatory effect of miR-460b-5p on the development of chicken skeletal muscles is still unclear. Therefore, miR-460b-5p was further used for functional validation at the cellular level in this study. The expression pattern of miR-460b-5p was investigated in proliferation and differentiation stages of chicken primary myoblasts. It was showed that the expression level of miR-460b-5p gradually decreased from the proliferation stage (GM 50%) to the lowest at 24 h of differentiation. As differentiation proceeded, miR-460b-5p expression increased significantly, reaching the highest and stabilizing at 72 h and 96 h of differentiation. Through mRNA quantitative analysis of proliferation marker genes, CCK-8 and Edu assays, miR-460b-5p was found to significantly facilitate the transition of myoblasts from G1 to S phase and promote chicken myoblast proliferation. mRNA and protein quantitative analysis of differentiation marker genes, as well as the indirect immunofluorescence results of myotubes, revealed that miR-460b-5p significantly stimulated myotube development and promote chicken myoblast differentiation. In addition, the target relationship was validated for miR-460b-5p according to the dual-luciferase reporter assay and mRNA quantitative analysis, which indicates that miR-460b-5p was able to regulate RBM19 expression by specifically binding to the 3' UTR of RBM19. In summary, miR-460b-5p has positive regulatory effects on the proliferation and differentiation of chicken myoblasts, and RBM19 is a target gene of miR-460b-5p.

Epigenetic Mechanisms in Hematologic Aging and Premalignant Conditions

Hematopoietic stem cells (HSCs) are essential for maintaining overall health by continuously generating blood cells throughout an individual's lifespan. However, as individuals age, the hematopoietic system undergoes significant functional decline, rendering them more susceptible to age-related diseases. Growing research evidence has highlighted the critical role of epigenetic regulation in this age-associated decline. This review aims to provide an overview of the diverse epigenetic mechanisms involved in the regulation of normal HSCs during the aging process and their implications in aging-related diseases. Understanding the intricate interplay of epigenetic mechanisms that contribute to aging-related changes in the hematopoietic system holds great potential for the development of innovative strategies to delay the aging process. In fact, interventions targeting epigenetic modifications have shown promising outcomes in alleviating aging-related phenotypes and extending lifespan in various animal models. Small molecule-based therapies and reprogramming strategies enabling epigenetic rejuvenation have emerged as effective approaches for ameliorating or even reversing aging-related conditions. By acquiring a deeper understanding of these epigenetic mechanisms, it is anticipated that interventions can be devised to prevent or mitigate the rates of hematologic aging and associated diseases later in life. Ultimately, these advancements have the potential to improve overall health and enhance the quality of life in aging individuals.

Emerging role and therapeutic implications of p53 in intervertebral disc degeneration

Lower back pain (LBP) is a common degenerative musculoskeletal disease that imposes a huge economic burden on both individuals and society. With the aggravation of social aging, the incidence of LBP has increased globally. Intervertebral disc degeneration (IDD) is the primary cause of LBP. Currently, IDD treatment strategies include physiotherapy, medication, and surgery; however, none can address the root cause by ending the degeneration of intervertebral discs (IVDs). However, in recent years, targeted therapy based on specific molecules has brought hope for treating IDD. The tumor suppressor gene p53 produces a transcription factor that regulates cell metabolism and survival. Recently, p53 was shown to play an important role in maintaining IVD microenvironment homeostasis by regulating IVD cell senescence, apoptosis, and metabolism by activating downstream target genes. This study reviews research progress regarding the potential role of p53 in IDD and discusses the challenges of targeting p53 in the treatment of IDD. This review will help to elucidate the pathogenesis of IDD and provide insights for the future development of precision treatments.

Ethyl maltol disrupt iron homeostasis in SH-SY5Y neuroblastoma cell line

Ethyl Maltol (EM) is a commonly used flavoring compound and has been reported to bind iron and facilitate iron transport. Since EM is membrane permeable, the potential that it disrupts intracellular iron homeostasis was investigated. EM increased the labile iron pool in SH-SY5Y cells and increased iron-responsive protein activity using a reporter assay in the HEK293 cells. EM induced the expression of transferrin receptor 1 messenger RNA (mRNA) and decreased the expression of ferritin light chain protein in SH-SY5Y cells. Expression of the iron-responsive amyloid precursor protein attenuated the effects of EM on these iron-responsive genes. EM treatment decreased cell viability and increased DNA damage. EM also increased the level of phosphorylated p53 and the expression of the p53-regulated genes, p21, and 14-3-3σ. The expression of amyloid precursor protein (APP) attenuated the effects of EM on viability, DNA damage, and the p53 response. Overall, we suggest that EM decreases cell viability through a mechanism involving the p53 pathway. The attenuated responses observed in cells expressing APP suggest that the effects of EM are due to disrupting iron homeostasis.

Gene expression analyses reveal potential mechanism of inorganic arsenic-induced apoptosis in zebrafish

Our previous study showed that sodium arsenite (200 mg/L) affected the nervous system and induced motor neuron development via the Sonic hedgehog pathway in zebrafish larvae. To gain more insight into the effects of arsenite on other signaling pathways, including apoptosis, we have performed quantitative polymerase chain reaction array-based gene expression analyses. The 96-well array plates contained primers for 84 genes representing 10 signaling pathways that regulate several biological functions, including apoptosis. We exposed eggs at 5 h postfertilization until the 72 h postfertilization larval stage to 200 mg/L sodium arsenite. In the Janus kinase/signal transducers and activators of transcription, nuclear factor κ-light-chain-enhancer of activated B cells, and Wingless/Int-1 signaling pathways, the expression of only one gene in each pathway was significantly altered. The expression of multiple genes was altered in the p53 and oxidative stress pathways. Sodium arsenite induced excessive apoptosis in the larvae. This compelled us to analyze specific genes in the p53 pathway, including cdkn1a, gadd45aa, and gadd45ba. Our data suggest that the p53 pathway is likely responsible for sodium arsenite-induced apoptosis. In addition, sodium arsenite significantly reduced global DNA methylation in the zebrafish larvae, which may indicate that epigenetic factors could be dysregulated after arsenic exposure. Together, these data elucidate potential mechanisms of arsenic toxicity that could improve understanding of arsenic's effects on human health.

Unlocking Early Cancer Detection: Exploring Biomarkers, Circulating DNA, and Innovative Technological Approaches

Research and development improvements in early cancer diagnosis have had a significant positive impact on health. In the treatment and prevention of cancer, early detection is essential. In this context, biomarkers are essential because they offer important information on the state of cells at any particular time. Cells go through unique changes when they shift from a healthy condition to a malignant state, changes that appropriate biomarkers may pick up. Recent advancements have been made to identify and characterize circulating cancer-specific mutations in cell-free circulating DNA derived from tumors and tumor cells. A patient's delay between the time they first detect symptoms and the time they contact a doctor has been noted for many cancer forms. The tumor's location and features significantly impact the presentation of symptoms judged appropriate for early diagnosis. Lack of knowledge of the severity of the symptoms may be one cause for this delay. Our review is largely focused on the ongoing developments of early diagnosis in the study of biomarkers, circulating DNA for diagnosis, the biology of early challenges, early symptoms, liquid biopsies, detectable by imaging, established tumor markers, plasma DNA technologies, gender differences, and artificial intelligence (AI) in diagnosis. This review aims to determine and evaluate Indicators for detecting early cancer, assessing medical conditions, and evaluating potential risks. For Individuals with a heightened likelihood of developing cancer or who have already been diagnosed, early identification is crucial for enhancing prognosis and raising the likelihood of effective treatment.

Integrated single-cell and bulk RNA sequencing analysis identifies a neoadjuvant chemotherapy-related gene signature for predicting survival and therapy in breast cancer

Neoadjuvant chemotherapy (NAC) is a well-established treatment modality for locally advanced breast cancer (BC). However, it can also result in severe toxicities while controlling tumors. Therefore, reliable predictive biomarkers are urgently needed to objectively and accurately predict NAC response. In this study, we integrated single-cell and bulk RNA-seq data to identify nine genes associated with the prognostic response to NAC: NDRG1, CXCL14, HOXB2, NAT1, EVL, FBP1, MAGED2, AR and CIRBP. Furthermore, we constructed a prognostic risk model specifically linked to NAC. The clinical independence and generalizability of this model were effectively demonstrated. Additionally, we explore the underlying cancer hallmarks and microenvironment features of this NAC response-related risk score, and further assess the potential impact of risk score on drug response. In summary, our study constructed and validated a nine-gene signature associated with NAC prognosis, which was accomplished through the integration of single-cell and bulk RNA data. The results of our study are of crucial significance in the prediction of the efficacy of NAC in BC, and may have implications for the clinical management of this disease.

Landscape of somatic mutated genes and inherited susceptibility genes in gynecological cancer

Traditionally, gynecological cancers have been classified based on histology. Since remarkable advancements in next-generation sequencing technology have enabled the exploration of somatic mutations in various cancer types, comprehensive sequencing efforts have revealed the genomic landscapes of some common forms of human cancer. The genomic features of various gynecological malignancies have been reported by several studies of large-scale genomic cohorts, including The Cancer Genome Atlas. Although recent comprehensive genomic profiling tests, which can detect hundreds of genetic mutations at a time from cancer tissues or blood samples, have been increasingly used as diagnostic clinical biomarkers and in therapeutic management decisions, germline pathogenic variants associated with hereditary cancers can also be detected using this test. Gynecological cancers are closely related to genetic factors, with approximately 5% of endometrial cancer cases and 20% of ovarian cancer cases being caused by germline pathogenic variants. Hereditary breast and ovarian cancer syndrome and Lynch syndrome are the two major cancer susceptibility syndromes among gynecological cancers. In addition, several other hereditary syndromes have been reported to be associated with gynecological cancers. In this review, we highlight the genes for somatic mutation and germline pathogenic variants commonly seen in gynecological cancers. We first describe the relationship between clinicopathological attributes and somatic mutated genes. Subsequently, we discuss the characteristics and clinical management of inherited cancer syndromes resulting from pathogenic germline variants in gynecological malignancies.

Sakuranin represses the malignant biological behaviors of human bladder cancer cells by triggering autophagy via activating the p53/mTOR pathway

OBJECTIVE

Sakura extract is a natural flavonoid compound that may have potential anti-tumor effects. The paper focuses on investigating Sakuranin mechanism on bladder cancer (BC) cells.

METHODS

BC cells (T24) were treated with different concentrations of Sakuranin, with 48-h IC50 determined. T24 cells were treated with Sakuranin at IC50, followed by assessment of cell proliferative/apoptotic/migrative/invasive activities by CCK-8, EdU and plate clone formation assays/flow cytometry/Transwell/scratch test. MMP-2 (migration and invasion-related protein) protein level was assessed by Western blot. Cell autophagy was evaluated by measuring the protein levels of autophagy markers (LC3-I/LC3-II/p62) through Western blot. The autophagy inhibitor 3-MA was used to validate the role of autophagy in the regulatory mechanism of Sakuranin in T24 cell behaviors. Furthermore, the activation of the p53/mTOR pathway in cells was detected and a combination of Sakuranin and p53 inhibitor Pifithrin-µ was adopted to explore the involvement of this pathway.

RESULTS

Sakuranin decreased T24 cell proliferation/EdU positive cell percentage/colony formation number and area/migration/invasion/scratch healing/MMP-2 protein level, and accelerated apoptosis. Sakuranin elevated the LC3-II/I ratio and lowered p62 level in T24 cells. 3-MA partially averted Sakuranin-mediated repression on cell malignant behaviors. Sakuranin upregulated p-p53 and p53 levels, and decreased the p-mTOR/mTOR ratio in T24 cells. The effects of Sakuranin on cell biological behaviors were partly annulled by Pifithrin-µ treatment.

CONCLUSION

Sakuranin suppressed T24 cell proliferation/migration/invasion, and enhanced apoptosis by potentiating autophagy through activating the p53/mTOR pathway. This study provided a theoretical basis for Sakuranin as a potential drug for clinical treatment of BC.

Identification of the natural chalcone glycoside hydroxysafflor yellow A as a suppressor of P53 overactivation-associated hematopoietic defects

Enhanced P53 signaling may lead to hematopoietic disorders, yet an effective therapeutic strategy is still lacking. Our study, along with previous research, suggests that P53 overactivation and hematopoietic defects are major consequences of zinc deficiency. However, the relationship between these two pathological processes remains unclear. In this study, we observed a severe reduction in the number of hematopoietic stem cells (HSCs) and multi-lineage progenitor cells in zebrafish treated with the zinc chelator N,N,N',N'-tetrakis(2-pyridylmethyl)ethylenediamine and showed the indispensable role of P53 signaling in the process. Next, we took advantage of HSCs-labeled transgenic zebrafish and conducted a highly efficient phenotypic screening for small molecules against P53-dependent hematopoietic disorders. Hydroxysafflor yellow A (HSYA), a natural chalcone glycoside, exhibited potent protection against hematopoietic failure in zinc-deficient zebrafish and strongly inhibited the P53 pathway. We confirmed the protective effect of HSYA in zinc-deficient mice bone marrow nucleated cells, which showed a significant suppression of P53 signaling and oxidative stress. Furthermore, the hematopoietic-protective activity of HSYA was validated using a mice model of myelotoxicity induced by 5-FU. In summary, our work provides an effective phenotypic screening strategy for identifying hematopoietic-protective agents and reveals the novel role of HSYA as a promising lead compound in rescuing hematopoietic disorders associated with P53 overactivation.

Elabela inhibits TRAF1/NF-κB induced oxidative DNA damage to promote diabetic foot ulcer wound healing

Diabetic foot ulcer (DFU) is a serious complication of diabetes. Elabela (ELA), a ligand of apelin receptor (APJ), was shown to promote angiogenesis and suppress inflammation. This study aimed to illustrate the role of ELA in DFU wound healing. A whole-skin defect model was constructed using db/m and db/db mice to observe the effects of ELA on wound healing. The function of ELA in endothelial cells cultured in high glucose medium was investigated. Administration of ELA in peri-wound area of db/db mice accelerated wound closure and reduced inflammatory infiltration. Indicators of DNA damage, elevated reactive oxygen species (ROS) levels and tail DNA amounts, were downregulated by ELA but compromised after TRAF1 overexpression. ELA-mediated inhibition of NF-κB phosphorylation improved cell migration and angiogenesis, which were blocked by APJ silencing. The findings imply that ELA suppresses TRAF1-mediated NF-κB signal activation, reducing ROS-related oxidative DNA damage and improving protection of endothelial function.

Comparison of TP53 Mutations in Myelodysplasia and Acute Leukemia Suggests Divergent Roles in Initiation and Progression

TP53 mutation predicts adverse prognosis in many cancers, including myeloid neoplasms, but the mechanisms by which specific mutations impact disease biology, and whether they differ between disease categories, remain unknown. We analyzed TP53 mutations in four myeloid neoplasm subtypes (MDS, AML, AML with myelodysplasia-related changes (AML-MRC), and therapy-related acute myeloid leukemia (tAML)), and identified differences in mutation types, spectrum, and hotspots between disease categories and compared to solid tumors. Missense mutations in the DNA-binding domain were most common across all categories, whereas inactivating mutations and mutations outside the DNA binding domain were more common in AML-MRC compared to MDS. TP53 mutations in MDS were more likely to retain transcriptional activity, and co-mutation profiles were distinct between disease categories and mutation types. Our findings suggest that mutated TP53 contributes to initiation and progression of neoplasia via distinct mechanisms, and support the utility of specific identification of TP53 mutations in myeloid malignancies.

Chemical mitophagy modulators: Drug development strategies and novel regulatory mechanisms

Maintaining mitochondrial homeostasis is a potential therapeutic strategy for various diseases, including neurodegenerative diseases, cardiovascular diseases, metabolic disorders, and cancer. Selective degradation of mitochondria by autophagy (mitophagy) is a fundamental mitochondrial quality control mechanism conserved from yeast to humans. Indeed, small-molecule modulators of mitophagy are valuable pharmaceutical tools that can be used to dissect complex biological processes and turn them into potential drugs. In the past few years, pharmacological regulation of mitophagy has shown promising therapeutic efficacy in various disease models. However, with the increasing number of chemical mitophagy modulator studies, frequent methodological flaws can be observed, leading some studies to draw unreliable or misleading conclusions. This review attempts (a) to summarize the molecular mechanisms of mitophagy; (b) to propose a Mitophagy Modulator Characterization System (MMCS); (c) to perform a comprehensive analysis of methods used to characterize mitophagy modulators, covering publications over the past 20 years; (d) to provide novel targets for pharmacological intervention of mitophagy. We believe this review will provide a panorama of current research on chemical mitophagy modulators and promote the development of safe and robust mitophagy modulators with therapeutic potential by introducing high methodological standards.

AI-powered discovery of a novel p53-Y220C reactivator

Introduction

The p53-Y220C mutation is one of the most common mutations that play a major role in cancer progression.

Methods

In this study, we applied artificial intelligence (AI)-powered virtual screening to identify small-molecule compounds that specifically restore the wild-type p53 conformation from p53-Y220C. From 10 million compounds, the AI algorithm selected a chemically diverse set of 83 high-scoring hits, which were subjected to several experimental assays using cell lines with different p53 mutations.

Results

We identified one compound, H3, that preferentially killed cells with the p53-Y220C mutation compared to cells with other p53 mutations. H3 increased the amount of folded mutant protein with wild-type p53 conformation, restored its transcriptional functions, and caused cell cycle arrest and apoptosis. Furthermore, H3 reduced tumorigenesis in a mouse xenograft model with p53-Y220C-positive cells.

Conclusion

AI enabled the discovery of the H3 compound that selectively reactivates the p53-Y220C mutant and inhibits tumor development in mice.

Accelerated replicative senescence of ataxia-telangiectasia skin fibroblasts is retained at physiologic oxygen levels, with unique and common transcriptional patterns

The genetic disorder, ataxia-telangiectasia (A-T), is caused by loss of the homeostatic protein kinase, ATM, and combines genome instability, tissue degeneration, cancer predisposition, and premature aging. Primary fibroblasts from A-T patients exhibit premature senescence when grown at ambient oxygen concentration (21%). Here, we show that reducing oxygen concentration to a physiological level range (3%) dramatically extends the proliferative lifespan of human A-T skin fibroblasts. However, they still undergo senescence earlier than control cells grown under the same conditions and exhibit high genome instability. Comparative RNA-seq analysis of A-T and control fibroblasts cultured at 3% oxygen followed by cluster analysis of differentially expressed genes and functional enrichment analysis, revealed distinct transcriptional dynamics in A-T fibroblasts senescing in physiological oxygen concentration. While some transcriptional patterns were similar to those observed during replicative senescence of control cells, others were unique to the senescing A-T cells. We observed in them a robust activation of interferon-stimulated genes, with undetected expression the interferon genes themselves. This finding suggests an activation of a non-canonical cGAS-STING-mediated pathway, which presumably responds to cytosolic DNA emanating from extranuclear micronuclei detected in these cells. Senescing A-T fibroblasts also exhibited a marked, intriguely complex alteration in the expression of genes associated with extracellular matrix (ECM) remodeling. Notably, many of the induced ECM genes encode senescence-associated secretory phenotype (SASP) factors known for their paracrine pro-fibrotic effects. Our data provide a molecular dimension to the segmental premature aging observed in A-T patients and its associated symptoms, which develop as the patients advance in age.

Targeting mutant p53 stabilization for cancer therapy

Over 50% cancer bears TP53 mutation, the highly stabilized mutant p53 protein drives the tumorigenesis and progression. Mutation of p53 not only cause loss-of-function and dominant-negative effects (DNE), but also results in the abnormal stability by the regulation of the ubiquitin-proteasome system and molecular chaperones that promote tumorigenesis through gain-of-function effects. The accumulation of mutant p53 is mainly regulated by molecular chaperones, including Hsp40, Hsp70, Hsp90 and other biomolecules such as TRIM21, BAG2 and Stat3. In addition, mutant p53 forms prion-like aggregates or complexes with other protein molecules and result in the accumulation of mutant p53 in tumor cells. Depleting mutant p53 has become one of the strategies to target mutant p53. This review will focus on the mechanism of mutant p53 stabilization and discuss how the strategies to manipulate these interconnected processes for cancer therapy.

A Comparative Study of Skin Changes in Different Species of Mice in Chronic Photoaging Models

This study aimed to design a novel mouse model of chronic photoaging. We used three different species of mice (C57BL/6J, ICR, and KM) to create a chronic photoaging model of the skin. The irradiation time was gradually increased for 40 consecutive days. The skins of the mice were removed on day 41 and subjected to staining to observe them for morphological changes. Immunohistochemistry was used to detect tumor necrosis factor-α (TNF-α) and p53 expression; superoxide dismutase (SOD) and malondialdehyde (MDA) were measured as well. Compared with C57BL/J mice, which showed hyperpigmentation, the irradiated skin of ICR and KM mice showed more obvious skin thickening and photoaging changes of the collagen and elastic fibers. KM mice had higher levels of inflammation, oxidative stress, and senescent cells. Compared with the 5-month-old KM mice, the photoaging changes of the 9-month-old KM mice were more pronounced, the SOD values were lower, and the MDA values were higher. In summary, KM mice have higher levels of abnormal elastic fibers, inflammation, cellular senescence, and oxidative stress than ICR mice, and are more suitable for studies related to chronic skin photoaging. C57BL/6J mice were found to be suitable for studies related to skin pigmentation due to photoaging.

Exposure to Cis- and Trans-regioisomers of S-(1,2-dichlorovinyl)-L-cysteine and S-(1,2-dichlorovinyl)-glutathione result in quantitatively and qualitatively different cellular effects in RPTEC/TERT1 cells

Bioactivation of trichloroethylene (TCE) via glutathione conjugation is associated with several adverse effects in the kidney and other extrahepatic tissues. Of the three regioisomeric conjugates formed, S-(1,2-trans-dichlorovinyl)-glutathione (1,2-trans-DCVG), S-(1,2-cis-dichlorovinyl)-glutathione and S-(2,2-dichlorovinyl)-glutathione, only 1,2-trans-DCVG and its corresponding cysteine-conjugate, 1,2-trans-DCVC, have been subject to extensive mechanistic studies. In the present study, the metabolism and cellular effects of 1,2-cis-DCVG, the major regioisomer formed by rat liver fractions, and 1,2-cis-DCVC were investigated for the first time using RPTEC/TERT1-cells as in vitro renal model. In contrast to 1,2-trans-DCVG/C, the cis-regioisomers showed minimal effects on cell viability and mitochondrial respiration. Transcriptomics analysis showed that both 1,2-cis-DCVC and 1,2-trans-DCVC caused Nrf2-mediated antioxidant responses, with 3µM as lowest effective concentration. An ATF4-mediated integrated stress response and p53-mediated responses were observed starting from 30µM for 1,2-trans-DCVC and 125µM for 1,2-cis-DCVC. Comparison of the metabolism of the DCVG regioisomers by LC/MS showed comparable rates of processing to their corresponding DCVC. No detectable N-acetylation was observed in RPTEC/TERT1 cells. Instead, N-glutamylation of DCVC to form N-γ-glutamyl-S-(dichlorovinyl)-L-cysteine was identified as a novel route of metabolism. The results suggest that 1,2-cis-DCVC may be of less toxicological concern for humans than 1,2-trans-DCVC, considering its lower intrinsic toxicity and lower rate of formation by human liver fractions.

Targeting the p53 signaling pathway in cancers: Molecular mechanisms and clinical studies

Tumor suppressor p53 can transcriptionally activate downstream genes in response to stress, and then regulate the cell cycle, DNA repair, metabolism, angiogenesis, apoptosis, and other biological responses. p53 has seven functional domains and 12 splice isoforms, and different domains and subtypes play different roles. The activation and inactivation of p53 are finely regulated and are associated with phosphorylation/acetylation modification and ubiquitination modification, respectively. Abnormal activation of p53 is closely related to the occurrence and development of cancer. While targeted therapy of the p53 signaling pathway is still in its early stages and only a few drugs or treatments have entered clinical trials, the development of new drugs and ongoing clinical trials are expected to lead to the widespread use of p53 signaling-targeted therapy in cancer treatment in the future. TRIAP1 is a novel p53 downstream inhibitor of apoptosis. TRIAP1 is the homolog of yeast mitochondrial intermembrane protein MDM35, which can play a tumor-promoting role by blocking the mitochondria-dependent apoptosis pathway. This work provides a systematic overview of recent basic research and clinical progress in the p53 signaling pathway and proposes that TRIAP1 is an important therapeutic target downstream of p53 signaling.

Activation of P53 pathway contributes to Xenopus hybrid inviability

Hybrid incompatibility as a kind of reproductive isolation contributes to speciation. The nucleocytoplasmic incompatibility between Xenopus tropicalis eggs and Xenopus laevis sperm (te×ls) leads to specific loss of paternal chromosomes 3L and 4L. The hybrids die before gastrulation, of which the lethal causes remain largely unclear. Here, we show that the activation of the tumor suppressor protein P53 at late blastula stage contributes to this early lethality. We find that in stage 9 embryos, P53-binding motif is the most enriched one in the up-regulated Assay for Transposase-Accessible Chromatin with high-throughput sequencing (ATAC-seq) peaks between te×ls and wild-type X. tropicalis controls, which correlates with an abrupt stabilization of P53 protein in te×ls hybrids at stage 9. Inhibition of P53 activity via either tp53 knockout or overexpression of a dominant-negative P53 mutant or Murine double minute 2 proto-oncogene (Mdm2), a negative regulator of P53, by mRNA injection can rescue the te×ls early lethality. Our results suggest a causal function of P53 on hybrid lethality prior to gastrulation.

GPR19 Coordinates Multiple Molecular Aspects of Stress Responses Associated with the Aging Process

G protein-coupled receptors (GPCRs) play a significant role in controlling biological paradigms such as aging and aging-related disease. We have previously identified receptor signaling systems that are specifically associated with controlling molecular pathologies associated with the aging process. Here, we have identified a pseudo-orphan GPCR, G protein-coupled receptor 19 (GPR19), that is sensitive to many molecular aspects of the aging process. Through an in-depth molecular investigation process that involved proteomic, molecular biological, and advanced informatic experimentation, this study found that the functionality of GPR19 is specifically linked to sensory, protective, and remedial signaling systems associated with aging-related pathology. This study suggests that the activity of this receptor may play a role in mitigating the effects of aging-related pathology by promoting protective and remedial signaling systems. GPR19 expression variation demonstrates variability in the molecular activity in this larger process. At low expression levels in HEK293 cells, GPR19 expression regulates signaling paradigms linked with stress responses and metabolic responses to these. At higher expression levels, GPR19 expression co-regulates systems involved in sensing and repairing DNA damage, while at the highest levels of GPR19 expression, a functional link to processes of cellular senescence is seen. In this manner, GPR19 may function as a coordinator of aging-associated metabolic dysfunction, stress response, DNA integrity management, and eventual senescence.

Role of condensates in modulating DNA repair pathways and its implication for chemoresistance

For cells, it is important to repair DNA damage, such as double strand and single strand DNA breaks, because unrepaired DNA can compromise genetic integrity, potentially leading to cell death or cancer. Cells have multiple DNA damage repair pathways that have been the subject of detailed genetic, biochemical, and structural studies. Recently, the scientific community has started to gain evidence that the repair of DNA double strand breaks may occur within biomolecular condensates and that condensates may also contribute to DNA damage through concentrating genotoxic agents used to treat various cancers. Here, we summarize key features of biomolecular condensates and note where they have been implicated in the repair of DNA double strand breaks. We also describe evidence suggesting that condensates may be involved in the repair of other types of DNA damage, including single strand DNA breaks, nucleotide modifications (e.g., mismatch and oxidized bases) and bulky lesions, among others. Finally, we discuss old and new mysteries that could now be addressed considering the properties of condensates, including chemoresistance mechanisms.

Synthesis and Antineoplastic Activity of a Dimer, Spiroindolinone Pyrrolidinecarboxamide

The mutation or function loss of tumour suppressor p53 plays an important role in abnormal cell proliferation and cancer generation. Murine Double Minute 2 (MDM2) is one of the key negative regulators of p53. p53 reactivation by inhibiting MDM2-p53 interaction represents a promising therapeutic option in cancer treatment. Here, to develop more effective MDM2 inhibitors with lower off-target toxicities, we synthesized a dimer, spiroindolinone pyrrolidinecarboxamide XR-4, with potent MDM2-p53 inhibition activity. Western blotting and qRT-PCR were performed to detect the impact of XR-4 on MDM2 and p53 protein levels and p53 downstream target gene levels in different cancers. Cancer cell proliferation inhibition and clonogenic activity were also investigated via the CCK8 assay and colony formation assay. A subcutaneous 22Rv1-derived xenografts mice model was used to investigate the in vivo anti-tumour activity of XR-4. The results reveal that XR-4 can induce wild-type p53 accumulation in cancer cells, upregulate the levels of the p53 target genes p21 and PUMA levels, and then inhibit cancer cell proliferation and induce cell apoptosis. XR-4 can also act as a homo-PROTAC that induces MDM2 protein degradation. Meanwhile, the in vivo study results show that XR-4 possesses potent antitumour efficacy and a favourable safety property. In summary, XR-4 is an interesting spiroindolinone pyrrolidinecarboxamide-derivative dimer with effective p53 activation activity and a cancer inhibition ability.

Multifunctional DNA Tetrahedron for Alzheimer's Disease Mitochondria-Targeted Therapy by MicroRNA Regulation

The principal hallmark of Alzheimer's disease (AD) is neuron mitochondrial dysfunction, whereas mitochondrial miRNAs potentially play important roles. Nevertheless, efficacious mitochondria organelle therapeutic agents for treatment and management of AD are highly advisable. Herein, we report a multifunctional DNA tetrahedron-based mitochondria-targeted therapeutic platform, termed tetrahedral DNA framework-based nanoparticles (TDFNs), which was modified with triphenylphosphine (TPP) for mitochondria-targeting, cholesterol (Chol) for crossing the central nervous system, and functional antisense oligonucleotide (ASO) for both AD diagnosis and gene silencing therapy. After injecting intravenously through the tail vein of 3 × Tg-AD model mice, TDFNs can both easily cross the blood brain barrier and accurately arrive at the mitochondria. The functional ASO could not only be detected via the fluorescence signal for diagnosis but also mediate the apoptosis pathway through knocking miRNA-34a down, leading to recovery of the neuron cells. The superior performance of TDFNs suggests the great potential in mitochondria organelle therapeutics.

p53-dependent DNA repair during the DNA damage response requires actin nucleation by JMY

The tumour suppressor p53 is a nuclear transcription factor with key roles during DNA damage to enable a variety of cellular responses including cell cycle arrest, apoptosis and DNA repair. JMY is an actin nucleator and DNA damage-responsive protein whose sub-cellular localisation is responsive to stress and during DNA damage JMY undergoes nuclear accumulation. To gain an understanding of the wider role for nuclear JMY in transcriptional regulation, we performed transcriptomics to identify JMY-mediated changes in gene expression during the DNA damage response. We show that JMY is required for effective regulation of key p53 target genes involved in DNA repair, including XPC, XRCC5 (Ku80) and TP53I3 (PIG3). Moreover, JMY depletion or knockout leads to increased DNA damage and nuclear JMY requires its Arp2/3-dependent actin nucleation function to promote the clearance of DNA lesions. In human patient samples a lack of JMY is associated with increased tumour mutation count and in cells results in reduced cell survival and increased sensitivity to DNA damage response kinase inhibition. Collectively, we demonstrate that JMY enables p53-dependent DNA repair under genotoxic stress and suggest a role for actin in JMY nuclear activity during the DNA damage response.