Targeting p53 for the treatment of cancer

PP2A adapter protein IER5 induces dephosphorylation and degradation of MDM2, thereby stabilizing p53

The tumor suppressor p53 activates transcription of the IER5 gene, which encodes an adapter protein of protein phosphatase PP2A. IER5 binds to both the B55 regulatory subunit of PP2A and PP2A's target proteins, facilitating PP2A/B55-catalyzed dephosphorylation of these proteins. Here, we show that IER5 functions as a positive regulator of p53 by inhibiting its ubiquitination, thereby increasing cellular p53 levels. Mechanistically, this effect of IER5 requires its nuclear localization and binding to both PP2A/B55 and the p53 ubiquitin E3 ligase MDM2. Importantly, IER5 fails to inhibit p53 ubiquitination in cells treated with the MDM2 inhibitor Nutlin-3. The IER5-PP2A/B55 complex dephosphorylates MDM2 at Ser166, leading to MDM2 ubiquitination and a reduction in nuclear MDM2. Altogether, our data provide evidence that IER5-PP2A/B55 regulates the nuclear balance between MDM2 and p53 via MDM2 dephosphorylation.

Therapeutic options for human papillomavirus-positive tonsil and base of tongue cancer

The incidences of human papillomavirus-positive (HPV+) tonsillar and base tongue squamous cell carcinomas (TSCC and BOTSCC) have increased in recent decades. Notably, HPV+ TSCC and BOTSCC have a significantly better prognosis than their HPV-negative counterparts when treated with current surgical options, radiotherapy, or intensified chemoradiotherapy. However, a cure is not achieved in 20% of patients with HPV+ TSCC/BOTSCC. Meanwhile, cured patients often present with severe chronic side effects. This necessitates novel tailored alternatives, such as targeted therapy, immune checkpoint inhibitors (ICIs), and treatment de-escalation, together with better follow-up. Current precision medicine therefore focuses on detecting predictive and driver cancer genes to better stratify patient treatment, provide those with poor prognostic markers targeted therapy, and select those with favorable markers for de-escalated therapy. Moreover, detecting cell-free HPV DNA (cfHPV DNA) in plasma before and after treatment has been attempted to improve follow-up. In this context, this perspective discusses the significance of optimally defining HPV+ status, which requires HPV DNA and p16INKa overexpression, using prognostic markers, such as high CD8+ T-cell counts and HPV E2 mRNA expression, tumor size, and following cfHPV DNA for patient selection for specific therapies. Clinical trials with ICI with/without chemotherapy, targeted therapy with specific inhibitors-such as phosphoinositide 3-kinase and fibroblast growth factor receptor inhibitors-or immune therapy with various HPV-based vaccines for treating recurrences have yielded promising results.

Interferon regulatory factor 1 contributes to metabolic dysfunction associated steatotic liver disease

AIMS

Non-alcoholic fatty liver disease (NAFLD) or metabolic dysfunction associated steatotic liver disease (MASLD), has reached epidemic levels in multiple regions worldwide and contributes to cirrhosis and hepatocellular carcinoma. We have previously reported that the CC motif chemokine ligand 11 (CCL11) is a key regulator of MASLD. Expression of interferon regulatory factor 1 (IRF1) can be up-regulated by CCL11 treatment in hepatocytes, the relevance of which is not clear. In the present study we investigated the role of IRF1 in NAFLD pathogenesis.

METHODS AND MATERIALS

MASLD was investigated in mice fed a high-fat high carbohydrate (HFHC) diet or in the genetically predisposed obese mice (db/db).

KEY FINDINGS

Hepatocytes from CCL11 knockout mice displayed a less severe MASLD phenotype, when treated with palmitic acid (PA), compared to wild type hepatocytes, which could be normalized by IRF1 over-expression. On the contrary, IRF1 knockdown in hepatocytes significantly down-regulated expression of pro-inflammatory mediators and dampened lipid accumulation induced by PA treatment. More importantly, IRF1 knockdown in hepatocytes led to amelioration of MASLD in mice. RNA-seq and CUT&Tag-seq identified pro-MASLD genes, including Osbpl3, Ddit4, and Ccl2, as potential targets for IRF1 in hepatocytes.

SIGNIFICANCE

Our data reveal a novel regulatory role of IRF1 in MASLD pathogenesis. Targeting IRF1 can be considered as a reasonable approach for MASLD intervention.

Design, synthesis and biological evaluation of sulfur-containing tetrahydroxanthones as potential anti-tumor agents

Given the rising incidence and mortality rates of cancer, the development of highly effective, low-toxicity therapeutics is critical. Xanthones, a class of natural secondary metabolites, are notable for their distinct structure and exhibit promising antitumor activity, underscoring their potential as scaffolds for drug design. Sulfur heterocycles are also valuable in the development of bioactive small molecules. Therefore, we explored the introduction of sulfur in the core structure of xanthones, leading to the synthesis of a series of sulfur-containing tetrahydroxanthones. The in vitro cytotoxicity of these compounds was evaluated using the CCK8 assay, revealing that several derivatives exhibit anti-proliferative effects against HepG2 cells. Among them, compound 4k displayed potent inhibitory activity with an IC50 value of 6.08 μM and showed favorable selectivity, exhibiting low toxicity toward normal cells. Further studies demonstrated that 4k inhibited colony formation and migration of HepG2 cells, and induced apoptosis.

Condensed tannins from Salix babylonica L. leaves induce apoptosis of human ovarian cancer cells through mitochondrial and PI3K/AKT/ERK signaling pathways

Condensed tannins, natural antioxidants, are widely known for their antitumor activity with low toxicity. However, the antitumor mechanism of Salix babylonica leaf condensed tannins (SCTs) remains unclear. Here, we purified bioactive SCTs and analyzed their structural characteristics, antitumor effects on human ovarian cancer (OC) cells as well as related potential mechanism. FT-IR, ESI-MS, and HPLC analyses demonstrated that SCTs primarily consist of procyanidins with (epi)catechin as the main flavan-3-ol extension unit. SCTs significantly inhibited the proliferation and migration of OVCAR3 and A2780 cells, induced G0/G1 cell cycle arrest, and promoted apoptosis. SCTs induced apoptosis through the mitochondrial apoptotic pathway by decreasing mitochondrial membrane potential, increasing intracellular reactive oxygen species generation, elevating the Bax/Bcl-2 ratio, and activating caspase-3. Network pharmacology analysis speculated that SCTs exert anti-ovarian cancer effects by targeting multiple targets and pathways, among which the PI3K/AKT/ERK pathway may be the main pathway of action. Western blot confirmed that SCTs inhibited the phosphorylation of AKT, MEK, and ERK. Moreover, SCTs dose-dependently impaired OVCAR3 tumor spheroid growth in three-dimensional culture models. These results suggested that SCTs induced apoptosis in OC cells by activating the mitochondrial-associated apoptosis pathway and inhibiting the PI3K/AKT/ERK signaling pathway, showing potential as therapeutic agents for OC.

An epigenetic regulator synergizes with alphavirus-mediated gene therapy via biomimetic delivery for enhanced cancer therapy

Gene therapy is promising for treating genetic disorders, but faces challenges in treating cancer due to the intricate genetic and immunosuppressive landscape of this disease. Here, we describe a technology combining alphavirus-based gene therapy with an epigenetic regulator via pyroptosis and immune checkpoints to address these challenges. A filamentous actin-mimicking liposomal delivery system, with high fusion efficiency, was developed that encapsulates the Semliki Forest virus (pSFV) DNA vector to deliver p53 and PDL1 scFv DNA, bypassing traditional endocytic barriers to deliver genes with high efficiency via membrane fusion. To enhance this combined therapy, the DNA methyltransferase inhibitor decitabine (DAC) was used to increase Gasdermin E (GSDME) expression, converting apoptosis to pyroptosis. This approach kills apoptosis-resistant tumor cells, and also promotes T cell infiltration and activation, facilitating an anti-PDL1 therapy and the systemic antitumor immune response. This multifaceted therapeutic strategy combines gene therapy with epigenetic regulation to significantly improve immune checkpoint therapy (ICT) effectiveness, offering a robust potential as a transformative cancer treatment.

Clinical pathological characteristics and prognostic analysis of renal primitive neuroectodermal tumours: a multicentre retrospective study of 16 cases in Northwest China

OBJECTIVE

Renal primitive neuroectodermal tumours (rPNETs) are extremely rare and highly aggressive malignancy, posing significant diagnostic and therapeutic challenges. This study aims to describe the clinicopathological characteristics, treatment strategies, and survival outcomes of 16 cases of rPNET from multiple centers in Northwest China, and to explore potential prognostic factors.

METHODS

A multicenter retrospective study was conducted, including 16 patients diagnosed with rPNET across five hospitals in Northwest China. Immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) were employed to assess the expression of molecular markers, including P53, BCL-2, Ki-67, and EWSR1 gene rearrangements. Survival analysis was performed using the Kaplan-Meier method, and prognostic factors were evaluated using univariate and multivariate Cox regression models.

RESULTS

The median age of the patients was 39 years, with a median Ki-67 proliferation index of 50%. P53 mutations were detected in 87.0% of cases, and BCL-2 positive expression was observed in 56.25% of cases. The median overall survival (OS) was 14 months. Univariate analysis revealed that age, tumor stage, BCL-2 expression, and Ki-67 index were significantly associated with OS. Multivariate analysis identified high Ki-67 expression (HR = 1.100, 95% CI: 1.030-1.174, p = 0.004) and negative BCL-2 expression (HR = 0.151, 95% CI: 0.026-0.888, p = 0.037) as independent risk factors for poor prognosis. Kaplan-Meier survival curves demonstrated that the median OS was significantly shorter in patients with high Ki-67 expression (12 months) compared to those with low Ki-67 expression (20 months) (Log-rank test, P < 0.01). Similarly, the median OS was significantly shorter in the BCL-2 negative group (10 months) compared to the BCL-2 positive group (24 months) (Log-rank test, P < 0.05).

CONCLUSION

The absence of rosette structures does not exclude the diagnosis of rPNET. BCL-2 and Ki-67 expression are significant prognostic factors, with high Ki-67 expression and negative BCL-2 expression associated with worse outcomes. These findings highlight the importance of molecular markers in risk stratification and treatment planning for rPNET.

Strategies for p53 Activation and Targeted Inhibitors of the p53-Mdm2/MdmX Interaction

p53 is a tumor suppressor gene and is regarded as one of the most crucial genes in protecting humans against cancer. The protein Mdm2 and its homolog MdmX serve as negative regulators of p53. In nearly half of cancer cells, there is an overexpression of Mdm2 and MdmX, which inhibit p53 activity. Furthermore, Mdm2's E3 ubiquitin ligase activity promotes the ubiquitination and degradation of p53. Therefore, blocking the interaction between p53 and Mdm2/MdmX to prevent the degradation of wild-type p53 is an effective strategy for inhibiting tumor growth. This paper primarily discusses the regulatory relationship between p53, MdmX and Mdm2, and provides a review of the current status of p53-Mdm2/MdmX inhibitors. It aims to offer a theoretical foundation and research direction for the future discovery and design of targeted inhibitors against the p53-Mdm2/MdmX interaction.

Association between decreased p53 expression, elevated serum CagA levels, and oral squamous cell carcinoma

OBJECTIVE

p53 is a key tumor suppressor, aCnd loss of p53 function promotes the progression of many cancers. Helicobacter Pylori (HP) is mainly involved in the progression of gastric carcinoma, but its role in Oral Squamous Cell Carcinoma (OSCC) is controversial. The primary objectives of this study were to investigate the expression levels of p53 in OSCC tissues and to examine the serum levels of CagA in OSCC patients. Additionally, the authors aimed to explore the potential association between p53 expression and CagA levels in OSCC.

METHOD

A total of 65 patients diagnosed with OSCC and 42 healthy volunteers were recruited in this study. The clinical pathological parameters of all patients were collected. Reverse transcription-quantitative polymerase chain reaction was performed to detect the expression of p53 in tissues. Receiver Operating Characteristics Curve (ROC) analysis was used to assess the sensitivity of p53 for the diagnosis of OSCC. The concentration of Cytotoxin-Associated gene A (CagA) in serum was assessed by enzyme-linked immuno sorbent assay.

RESULTS

The results indicated that the p53 expression in oral mucosal tissues was downregulated while the concentration of CagA in serum was increased in OSCC patients. Besides, p53 expression was correlated with tumor stage. OSCC patients showed a higher HP positive rate than in healthy people.

CONCLUSIONS

In conclusion, this study demonstrated that decreased p53 expression and elevated serum CagA levels might be correlated with OSCC progression and diagnosis.

KT-253, a Novel MDM2 Degrader and p53 Stabilizer, Has Superior Potency and Efficacy than MDM2 Small-Molecule Inhibitors

Murine double minute 2 (MDM2) is an E3 ligase that inhibits the tumor suppressor protein p53. Clinical trials employing small-molecule MDM2/p53 interaction inhibitors have demonstrated limited activity, underscoring an unmet need for a better approach to target MDM2. KT-253 is a highly potent and selective heterobifunctional degrader that overcomes the MDM2 feedback loop seen with small-molecule MDM2/p53 interaction inhibitors and induces apoptosis in a range of hematologic and solid tumor lines. A single intravenous dose of KT-253 triggered rapid apoptosis and sustained tumor regression in p53 wild-type acute myeloid leukemia and acute lymphoblastic leukemia xenograft models. Additionally, a single intravenous dose of KT-253 in combination with standard-of-care venetoclax overcame venetoclax resistance in an acute myeloid leukemia xenograft model. The data herein define the therapeutic potential of KT-253 and support its clinical development in a range of hematologic and solid p53 wild-type malignancies, as a monotherapy and in combination with standard-of-care agents.

Correlating p53 immunostaining patterns with somatic TP53 mutation and functional properties of mutant p53 in triple-negative breast cancer

AIMS

Immunohistochemical (IHC) staining of p53 is a potential marker for TP53 mutations in various cancers. However, criteria for predicting TP53 mutations in triple-negative breast cancer (TNBC) using p53 IHC staining are not yet established. We aim to correlate p53 IHC expression patterns with TP53 mutation status in TNBC.

METHODS AND RESULTS

A total of 113 TNBC cases were analysed for p53 IHC staining pattern and somatic TP53 mutation using whole-exome sequencing. Functional properties of TP53 mutations were determined using the National Cancer Institute (NCI) TP53 database. P53 IHC patterns were categorized as nuclear overexpression (n = 58), null pattern (n = 40), wildtype (n = 15), cytoplasmic (n = 5), and subclonal (n = 5). The cutoff for predictive p53 nuclear overexpression was determined to be 80%, which strongly correlated with TP53 mutations. Notably, p53 overexpression had a positive predictive value (PPV) of 83% for missense or in-frame mutations, while the null pattern showed a PPV of 85% for detecting nonsense, frameshift, or splicing mutations. P53 overexpression was significantly linked to missense mutations within the DNA-binding domain (DBD) exhibiting gain-of-function (GOF) or dominant-negative effect (DNE). Cases exhibiting cytoplasmic expression correlated with nonsense or frameshift mutations in the DBD, nuclear localization signal (NLS), or splice sites. Cases with subclonal p53 staining patterns were associated with TP53 mutations.

CONCLUSION

Our study proposes newly defined criteria for interpreting p53 immunostaining patterns in TNBC, potentially allowing for the prediction of TP53 mutation types and their functional implications.

Renal ewing sarcoma in a young female: a case report and review of targeted therapy

Ewing sarcoma (ES) is an aggressive neoplasm predominantly affecting pediatric and adolescent populations. Renal involvement in ES is exceedingly rare, representing less than 1% of all renal malignancies. Herein, we present the case of a 22-year-old female diagnosed with renal Ewing sarcoma (RES) accompanied by renal vein thrombosis. The patient reported a one-month history of persistent left lumbar pain, prompting hospitalization. Magnetic resonance imaging identified an extensive left suprarenal mass measuring 13.5 × 10.5 × 4.5 cm, with concurrent renal vein thrombosis. The comprehensive evaluation of histopathology, immunohistochemistry and molecular genetics confirmed RES. The treatment included radical left nephrectomy, followed by adjuvant chemotherapy (i.e., vincristine, epirubicin and cyclophosphamide) after surgery. Genetic analysis of the tumor revealed mutations in P53 and STGA2. Follow-up contrast-enhanced computed tomography scans of the patient demonstrated metastatic progression to the pancreas. The patient passed away after a 7-month follow-up period. This article reviews our treatment experience and recent developments in targeted therapies. Aiming to provide new approaches for the treatment of RES, this combines next-generation sequencing technology with targeted therapy to promote the optimization of targeted treatments.

The key vulnerabilities and therapeutic opportunities in the USP7-p53/MDM2 axis in cancer

The MDM2/MDMX-p53 circuitry is essential for controlling the development, apoptosis, immune response, angiogenesis, senescence, cell cycle progression, and proliferation of cancer cells. Research has demonstrated that USP7 exerts strong control over p53, MDM2, and MDMX stability, with multiple mediator proteins influencing the USP7-p53-MDM2/MDMX axis to modify p53 expression level and function. In cases where p53 is of the wild type (Wt-p53) in tumors, inhibiting USP7 promotes the degradation of MDM2/MDMX, leading to the activation of p53 signaling. This, in turn, results in cell cycle arrest and apoptosis. Hence, targeting USP7 presents a promising avenue for cancer therapy. Targeting USP7 in tumors that harbor mutant p53 (Mut-p53) is unlikely and remains largely unexplored due to the existence of numerous USP7 targets that function independently of p53. Considering that Mut-p53 exhibits resistance to degradation by MDM2 and other E3 ligases and also shares the same signaling pathways as Wt-p53, it is reasonable to suggest that USP7 may play a role in stabilizing Mut-p53. However, there is still much to be done in this area. If the hypothesis is correct, USP7 may be a potent target in cancers containing both Wt-p53 and Mut-p53.

Development of Potent and Selective CK1α Molecular Glue Degraders

Molecular glue degraders (MGDs) are small molecules that facilitate proximity between a target protein and an E3 ubiquitin ligase, thereby inducing target protein degradation. Glutarimide-containing compounds are MGDs that bind cereblon (CRBN) and recruit neosubstrates. Through explorative synthesis of a glutarimide-based library, we discovered a series of molecules that induce casein kinase 1 alpha (CK1α) degradation. By scaffold hopping and rational modification of the chemical scaffold, we identified an imidazo[1,2-a]pyrimidine compound that induces potent and selective CK1α degradation. A structure-activity relationship study of the lead compound, QXG-6442, identified the chemical features that contribute to degradation potency and selectivity compared to other frequently observed neosubstrates. The glutarimide library screening and structure-activity relationship medicinal chemistry approach we employed is generally useful for developing new molecular glue degraders toward new targets of interest.

Advances in the study of CCT3 in malignant tumors: A review

Malignant tumors are among the leading causes of death worldwide, with their underlying mechanisms remaining largely unclear. Tumorigenesis is a complex process involving multiple factors, genes, and pathways. Tumor cells are characterized by abnormal proliferation, infiltration, invasion, and metastasis. Improving tumor diagnosis rates and identifying novel molecular therapeutic targets are of great significance for the advancement of modern medicine. Chaperonin containing TCP-1 subunit 3 (CCT3) is one of the subunits of the chaperonin containing TCP-1 complex, a molecular chaperone involved in protein folding and remodeling. CCT3 plays a crucial role in maintaining protein homeostasis, with key substrates including tubulin and actin. In recent years, CCT3 has been reported to be abnormally expressed in various cancers, correlating with prognosis and therapeutic outcomes. In this review, we summarize the basic structure and function of chaperonin containing TCP-1 complex and CCT3, and discuss the role of CCT3 in tumor development. Additionally, we explore its potential applications in cancer diagnosis and treatment.

Anlotinib enhances the pro-apoptotic effect of APG-115 on acute myeloid leukemia cell lines by inhibiting the P13K/AKT signaling pathway

BACKGROUND

APG-115 is a novel small-molecule selective inhibitor that destabilizes the p53-MDM2 complex and activates p53-mediated apoptosis in tumor cells. Anlotinib inhibits tumor angiogenesis and promotes apoptosis. In this study, we investigated the apoptotic effect and potential mechanism of APG-115 and anlotinib combination on AML cell lines with different p53 backgrounds.

MATERIAL AND METHODS

The IC50 values ​of APG-115 and anlotinib were detected by CCK-8 assay. The apoptosis rate of AML cells was evaluated by Annexin-V and PI double staining. Transcriptome sequencing was performed on the MOLM16 cell line treated with APG-115 and anlotinib, and differential analysis and enrichment analysis were performed. Real-time quantitative PCR and Western blot were used to detect the changes in cell cycle and pathway-related genes and proteins in AML cell lines after drug treatment. In vivo experiments, the anti-leukemia effects of APG-115 and anlotinib on AML xenograft mouse models were evaluated.

RESULTS

APG-115 and anlotinib could independently promote AML cell apoptosis, and the combination of the two drugs could produce a synergistic effect. Transcriptome sequencing showed that compared with the APG-115 monotherapy group, the differentially expressed genes were mainly enriched in the MDM2-p53 and PI3K/AKT pathways. In vivo experiments showed that compared with AML xenograft mice treated with either drug alone, AML progression was slowed in AML xenograft mice treated with APG-115 and anlotinib.

CONCLUSION

In vivo and in vitro experimental have shown that APG-115 combined with anlotinib can promote AML cells apoptosis and inhibit the progression of disease is independent of the p53 status.

The correlation between mitochondria-associated endoplasmic reticulum membranes (MAMs) and Ca2+ transport in the pathogenesis of diseases

Mitochondria and the endoplasmic reticulum (ER) are vital organelles that influence various cellular physiological and pathological processes. Recent evidence shows that about 5%-20% of the mitochondrial outer membrane is capable of forming a highly dynamic physical connection with the ER, maintained at a distance of 10-30 nm. These interconnections, known as MAMs, represent a relatively conserved structure in eukaryotic cells, acting as a critical platform for material exchange between mitochondria and the ER to maintain various aspects of cellular homeostasis. Particularly, ER-mediated Ca2+ release and recycling are intricately associated with the structure and functionality of MAMs. Thus, MAMs are integral in intracellular Ca2+ transport and the maintenance of Ca2+ homeostasis, playing an essential role in various cellular activities including metabolic regulation, signal transduction, autophagy, and apoptosis. The disruption of MAMs observed in certain pathologies such as cardiovascular and neurodegenerative diseases as well as cancers leads to a disturbance in Ca2+ homeostasis. This imbalance potentially aggravates pathological alterations and disease progression. Consequently, a thorough understanding of the link between MAM-mediated Ca2+ transport and these diseases could unveil new perspectives and therapeutic strategies. This review focuses on the changes in MAMs function during disease progression and their implications in relation to MAM-associated Ca2+ transport.

Deciphering the Expression, Functional Role, and Prognostic Significance of P53 in Cervical Cancer Through Bioinformatics Analysis

Background

Cervical cancer (CC) poses a persistent global health challenge, and it increases the mortality risk among women. P53 gene plays a pivotal role in CC regulation; yet, a comprehensive exploration of its expression levels and prognostic relevance is not fully understood.

Aim

The aim of this research was to utilize bioinformatics analysis on publicly available patient data to investigate and understand the expression patterns of the TP53 gene in CC.

Materials and Methods

The study utilizes the TIMER 2.0 and UALCAN databases to assess TP53 expression and its relationship with immune cell infiltration in CC. Additionally, genetic alterations in TP53 are explored using the cBioPortal database. Functional enrichment analysis unveils the molecular processes associated with TP53. Kaplan-Meier analysis examines TP53 prognostic significance.

Results

The study reveals that TP53 expression is significantly up regulated in CC, potentially driven by genetic alterations. TP53 expression positively correlates with immune cell infiltration, including CD8 + T cells, CD4 + T cells, neutrophils, and macrophages, suggesting its role in shaping the tumor microenvironment. Functional analysis identifies TP53 involvement in essential cellular processes, including chromatin assembly, DNA conformation change, and carbohydrate kinase activity. Kaplan-Meier analysis highlights the prognostic significance of TP53, showing a poorer overall survival in CC patients with high TP53 expression.

Conclusion

The results underscore the prognostic potential of P53 in CC and its utility as a biomarker for assessing prognosis associated to tumor-immune infiltration. This study provides valuable insights into the multifaceted role of P53 in cervical carcinogenesis and its implications for therapeutic interventions and personalized medicine.

Small molecules that targeting p53 Y220C protein: mechanisms, structures, and clinical advances in anti-tumor therapy

The p53 protein is regarded as the "Guardian of the Genome," but its mutation is tumor progression and present in more than half of malignant tumors. The pro-metastatic property of mutant p53 makes a strong argument for targeting mutant p53 with new therapeutic strategies. However, mutant p53 was considered as a challenging target for drug discovery due to the lack of small molecular binding pockets. Among them, mutant p53 Y220C creates a narrow crevice since the side chains dynamics on protein surface, which is suitable for designing small molecules to occupy the cavity and recovery the tumor suppressing function. Here, we describe the mechanism of p53 related signal pathway and how p53 Y220C regulate the tumorigenesis. We review the two types of p53 Y220C modulators including restoring the conformation of mutant p53 Y220C protein to wild-type p53 protein and recruiting histone acetyltransferase p300/CBP to acetylate p53 Y220C thus enables p53 Y220C dependent upregulation of apoptotic genes and downregulation of DNA damage response pathways. We also report clinical advances and challenges of these molecules in p53 Y220C medicated tumor therapy.

Reprogramming of Glucose Metabolism for Revisiting Hepatocellular Carcinoma Resistance to Transcatheter Hepatic Arterial Chemoembolization

Hepatocellular carcinoma (HCC) is recognized globally as one of the most lethal tumors, presenting a significant menace to patients' lives owing to its exceptional aggressiveness and tendency to recur. Transcatheter hepatic arterial chemoembolization (TACE) therapy, as a first-line treatment option for patients with advanced HCC, has been proven effective. However, it is disheartening that nearly 40 % of patients exhibit resistance to this therapy. Consequently, this review delves into the metabolic aspects of glucose metabolism to explore the underlying mechanisms behind TACE treatment resistance and to propose potentially fruitful therapeutic strategies. The ultimate objective is to present novel insights for the development of personalized treatment methods targeting HCC.

Molecular Mechanisms of Synergistic Effect of PRIMA-1met and Oxaliplatin in Colorectal Cancer With Different p53 Status

BACKGROUND

The toxicity and drug resistance associated with oxaliplatin (L-OHP) limit its long-term use for colorectal cancer (CRC) patients. p53 mutation is a common genetic trait of CRC. PRIMA-1met (APR-246, eprenetapopt) restores the DNA-binding capacity of different mutant P53 proteins. PRIMA-1met has progressed to the Phase III clinical trial. Our study explores the combination therapy of PRIMA-1met and L-OHP for CRC with different p53 status.

METHODS

Cell viability was assessed with Cell Counting Kit-8 (CCK-8) assay and combination index (CI) was calculated using The Chou-Talalay method. We also employed wound healing assay and colony formation assay to determine the effect of L-OHP, PRIMA-1met and their combination. Weighted gene co-expression network analysis (WGCNA) of RNA-seq data was conducted to identify key modules and central genes related to different treatment modalities. Xenograft CRC mouse model was used to assess the combination treatment in vivo.

RESULTS

Our findings showed heightened cytotoxicity and inhibition of migration, and colony formation in CRC cells treated with both drugs, irrespective of p53 status, presenting a promising avenue for addressing L-OHP resistance and toxicity. RNA-seq analysis revealed differential responses between p53-wide type HCT116 and p53-mutant DLD-1 cells, with pathway alterations implicated in tumorigenesis. WGCNA identified key modules and hub genes associated with combination therapy response. In vivo studies demonstrated enhanced efficacy of combined therapy over PRIMA-1met alone, while mitigating L-OHP-induced toxicity.

CONCLUSIONS

In summary, our research reveals the differential molecular mechanisms of combined PRIMA-1met and L-OHP in CRC with wild type p53 and mutant p53. Our data not only demonstrate that this combined regimen exerts synergistic anti-CRC effect in vitro and in vivo, but also suggest the benefit of PRIMA-1met on prevention of L-OHP-related side effects. These findings underscore the clinical potential of PRIMA-1met-L-OHP combination therapy in CRC, offering enhanced efficacy and reduced toxicity, warranting further clinical investigation.

The role of acetylation and deacetylation in cancer metabolism

As a hallmark of cancer, metabolic reprogramming adjusts macromolecular synthesis, energy metabolism and redox homeostasis processes to adapt to and promote the complex biological processes of abnormal growth and proliferation. The complexity of metabolic reprogramming lies in its precise regulation by multiple levels and factors, including the interplay of multiple signalling pathways, precise regulation of transcription factors and dynamic adjustments in metabolic enzyme activity. In this complex regulatory network, acetylation and deacetylation, which are important post-translational modifications, regulate key molecules and processes related to metabolic reprogramming by affecting protein function and stability. Dysregulation of acetylation and deacetylation may alter cancer cell metabolic patterns by affecting signalling pathways, transcription factors and metabolic enzyme activity related to metabolic reprogramming, increasing the susceptibility to rapid proliferation and survival. In this review, we focus on discussing how acetylation and deacetylation regulate cancer metabolism, thereby highlighting the central role of these post-translational modifications in metabolic reprogramming, and hoping to provide strong support for the development of novel cancer treatment strategies. KEY POINTS: Protein acetylation and deacetylation are key regulators of metabolic reprogramming in tumour cells. These modifications influence signalling pathways critical for tumour metabolism. They modulate the activity of transcription factors that drive gene expression changes. Metabolic enzymes are also affected, altering cellular metabolism to support tumour growth.

Innovative Bacterial Therapies and Genetic Engineering Approaches in Colorectal Cancer: A Review of Emerging Strategies and Clinical Implications

Colorectal cancer (CRC) is considered a widespread cancer, ranking second in mortality and incidence among cancer patients worldwide. CRC develops from adenoma to carcinoma through the dynamic interplay of genetic and environmental factors. The conventional modes of treatment, including operation, chemotherapy, and irradiation, are associated with significant challenges, such as drug resistance and toxicity, necessitating the exploration of new treatment modalities. These difficulties reveal the necessity of the emergence of new therapeutic approaches. This review mainly emphasizes the bacterial-based therapies that have recently developed like the engineered bacteriophage therapy and bacterial immunotherapy that pale the existing chemotherapy in terms of toxicity but are effective in killing tumor cells. Also, it also investigates various molecular genetic engineering strategies such as CRISPR-Cas9, CRISPR prime editing and gene silencing to achieve better targeting of CRC. Implementing these new approaches into the forefront of CRC treatment may bring better, more effective therapy with fewer side effects on patients' quality of life.

BTF3 affects hepatocellular carcinoma progression by transcriptionally upregulating PDCD2L and inactivating p53 signaling

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors, with the characteristics of high mortality and low 5-year survival rate. The potential role of BTF3 and PDCD2L in HCC remains unclear. Our study found that BTF3 expression was upregulated in hepatocellular carcinoma tissues, and its high expression was associated with poor prognosis. Knockdown of BTF3 significantly inhibited proliferation and promoted apoptosis of hepatocellular carcinoma cells by cell function assay. Mechanistically, BTF3 plays an oncogenic role by regulating the transcriptional expression of PDCD2L, which promotes proliferation and inhibits apoptosis of HCC cells by restraining the p53 pathway. In conclusion, our results suggest that BTF3 induces malignant progression of HCC by acting as a transcription factor that promotes the transcription of PDCD2L and influences the p53 pathway and that the BTF3/PDCD2L/P53 axis may be a future therapeutic strategy for HCC patients.

p53: The Multifaceted Roles of Covalent Modifications in Cancer

The p53 protein has attracted huge research interest over several decades due to its role as one of the most important tumor suppressors in mammals, which orchestrates a synchronous response from normal cells in the body to various forms of stress. The diverse cellular activities of the p53 protein are regulated mainly via its post-translational modifications (PTMs). PTMs affect p53 on several levels: at the level of the assembly of tetrameric complexes on DNA to transactivate its target genes, at the level of the assembly of tetrameric complexes on DNA to transactivate its target genes; at the level of proteolysis in the absence of stress; and on the contrary, at the level of augmented protein stability in response to stress signals. Disruptions in these regulatory mechanisms can lead to deviations from normal cellular function, boosting tumor initiation and progression. Conversely, targeted interventions in these pathways could prove beneficial for the development of antitumor therapies. Advancing our understanding of p53 modifiers and the proteins involved in its regulation equips researchers with an expanded toolkit for studying cellular processes and for developing biologically active molecules that influence p53-mediated responses.

Role of Proteins in Oncology: Advances in Cancer Diagnosis, Prognosis, and Targeted Therapy-A Narrative Review

Modern oncology increasingly relies on the role of proteins as key components in cancer diagnosis, prognosis, and targeted therapy. This review examines advancements in protein biomarkers across several cancer types, including breast cancer, lung cancer, ovarian cancer, and hepatocellular carcinoma. These biomarkers have proven critical for early detection, treatment response monitoring, and tailoring personalized therapeutic strategies. The article highlights the utility of targeted therapies, such as tyrosine kinase inhibitors and monoclonal antibodies, in improving treatment efficacy while minimizing systemic toxicity. Despite these advancements, challenges like tumor resistance, variability in protein expression, and diagnostic heterogeneity persist, complicating universal application. The review underscores future directions, including the integration of artificial intelligence, advanced protein analysis technologies, and the development of combination therapies to overcome these barriers and refine personalized cancer treatment.

Signaling pathways in HPV-induced cervical cancer: Exploring the therapeutic promise of RNA modulation

Cervical cancer, originating from the epithelial tissue of the uterine cervix, constitutes the most commonly diagnosed malignancy among women worldwide. The predominant etiological factor underpinning cervical carcinogenesis is persistent infection with high-risk human papillomavirus (HPV) genotypes, notably HPV-16 and HPV-18. Oncoproteins encoded by high-risk HPV interfere with multiple essential cellular signaling cascades. Specifically, E5, E6, and E7 proteins disrupt the signaling pathways like p53, retinoblastoma tumor suppressor protein (pRB), The phosphoinositide 3 kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR), epidermal growth factor receptor (EGFR), mitogen-activated protein kinases (MAPK)/extracellular signal-regulated kinases (ERK), and Wnt/β-catenin, promoting HPV-mediated carcinogenesis. This dysregulation disrupts cell cycle control, apoptosis, and metastasis through modulation of microRNAs (miRNA) and key cellular processes. The novel therapeutic interventions for HPV prevention and detection are fundamental to patient management. RNA-based treatment modalities offer the potential for manipulating critical pathways involved in cervical carcinogenesis. RNA therapeutics offer novel approaches to drug development by targeting intracellular genetic elements inaccessible to conventional modalities. Additional advantages include rapid design, synthesis, and a reduced genotoxic profile compared to DNA-based therapies. Despite beneficial attributes, system stability and efficient delivery remain critical parameters. This study assessed the intricate relationship between HPV, cervical cancer, and various signaling pathways. The study explores miRNAs' diagnostic and therapeutic potential, mall interfering RNAs (siRNAs), and long non-coding RNAs (lncRNAs)in cervical cancer management. The review highlights the prospect of RNA-targeted therapies to modulate specific cancer signaling pathways. This approach offers a novel strategy for cervical cancer treatment through precise regulation of cancer signaling. Future research should concentrate on developing RNA-targeted interventions to improve cervical cancer treatment outcomes through increased therapeutic efficacy and specificity.

TAF15 inhibits p53 nucleus translocation and promotes HCC cell 5-FU resistance via post-transcriptional regulation of UBE2N

Chemotherapy resistance is an important factor responsible for the low 5-year survival rate of hepatocellular carcinoma (HCC) patients. Ubiquitin-conjugating enzyme E2N (UBE2N) is a cancer-associated ubiquitin-conjugating enzyme that is expressed in HCC tissues, and its high expression is associated with a poor prognosis. This study explored the role played by UBE2N in development of 5-fluorouracil (5-FU) resistance in HCC cells. Three HCC cell lines (HepG2 [p53 wild type], Huh7 [p53 point mutant type], Hep3B [p53 non-expression type]), and one normal liver cell line (MIHA) were used in our present study. The IC50 value of 5-FU was determined using a cell counting kit-8 (CCK-8) assay. Cell viability was assessed by colony formation assays. TUNEL assays and flow cytometry were used to analyze cell apoptosis. RNA pull-down and RNA immunoprecipitation (RIP) assays were performed to confirm the binding relationship between UBE2N mRNA and TAF15 protein. Our results showed that TAF15 and UBE2N were highly expressed in HCC cells. UBE2N inhibited the translocation of p53 protein into the cell nucleus to increase 5-FU resistance, as reflected by an increased IC50 value, an increase in cell viability, and a reduction in cell apoptosis. Overexpression of p53 reduced 5-FU resistance, but that effect could be reversed by UBE2N overexpression. TAF15 protein bound to and stabilized UBE2N mRNA, thereby inhibiting p53 translocation into the nucleus and promoting 5-FU resistance in HCC cells. Collectively, our present study identified a novel mechanism by which TAF15/UBE2N regulates p53 distribution to increase 5-FU resistance. Our results also suggest potential therapeutic strategies for treating HCC.

Licochalcone A decreases cancer cell proliferation and enhances ferroptosis in acute myeloid leukemia through suppressing the IGF2BP3/MDM2 cascade

Licochalcone A (Lico A), a naturally bioactive flavonoid, has shown antitumor activity in several types of cancers. However, few studies have focused on its effect on acute myeloid leukemia (AML). Cell viability and colony formation potential were detected by CCK-8 assay and colony formation assay, respectively. Cell cycle distribution and apoptosis were assessed by flow cytometry. Ferroptosis was assessed by measuring reactive oxygen species (ROS), lipid ROS, malondialdehyde (MDA), and glutathione (GSH). Protein expression levels were determined by immunoblotting and immunohistochemistry (IHC), and mRNA expression was detected by real-time qPCR. The m6A modification of MDM2 mRNA was verified by methylated RNA immunoprecipitation (MeRIP) assay, and the interaction of IGF2BP3 and MDM2 mRNA was analyzed by RIP assay. Actinomycin D was used to evaluate mRNA stability. The efficacy of Lico A in vivo was examined by a murine xenograft model. Lico A suppressed cell proliferation and induced ferroptosis in MOLM-13 and U-937 in vitro, and slowed the growth of xenograft tumors in vivo. IGF2BP3 was highly expressed in human AML specimens and cells, and Lico A suppressed IGF2BP3 expression in AML cells. Lico A exerted the anti-proliferative and pro-ferroptosis effects by downregulating IGF2BP3. Moreover, IGF2BP3 enhanced the stability and expression of MDM2 mRNA through an m6A-dependent manner. Downregulation of IGF2BP3 impeded AML cell proliferation and enhanced ferroptosis via repressing MDM2. Furthermore, Lico A could affect the MDM2/p53 pathway by downregulating IGF2BP3 expression. Lico A exerts the anti-proliferative and pro-ferroptosis activity in AML cells by affecting the IGF2BP3/MDM2/p53 pathway, providing new evidence for Lico A as a promising agent for the treatment of AML.

USP36 promotes colorectal cancer progression through inhibition of p53 signaling pathway via stabilizing RBM28

Colorectal cancer (CRC) stands as the second most common cause of cancer-related mortality globally and p53, a widely recognized tumor suppressor, contributes to the development of CRC. Ubiquitin-specific protease 36 (USP36), belonging to the deubiquitinating enzyme family, is involved in tumor progression across multiple cancers. However, the underlying molecular mechanism in which USP36 regulates p53 signaling pathway in CRC is unclear. Here, our study revealed that USP36 was increased in CRC tissues and associated with unfavorable prognosis. Functionally, elevated USP36 could promote proliferation, migration, and invasion of CRC cells in vitro and in vivo. Mechanistically, USP36 could interact with and stabilize RBM28 via deubiquitination at K162 residue. Further, upregulated RBM28 could bind with p53 to suppress its transcriptional activity and therefore inactivate p53 signaling pathway. Collectively, our investigation identified the novel USP36/RBM28/p53 axis and its involvement in promoting cell proliferation and metastasis in CRC, which presents a promising therapeutic strategy for CRC treatment.

Potential Anticancer Effects of Isoflavone Prunetin and Prunetin Glycoside on Apoptosis Mechanisms

Cancer is a deadly disease caused by cells that deviate from the normal differentiation and proliferation behaviors and continue to multiply. There is still no definitive cure, and many side effects occur even after treatment. However, apoptosis, one of the programs imprinted on cells, is becoming an important concept in controlling cancer. Flavonoids are polyphenolic compounds found in plants, are naturally bioactive compounds, have been studied for their anticancer effects, and have fewer side effects than chemical treatments. Isoflavones are phytoestrogens belonging to the flavonoid family, and this review discusses in depth the potential anticancer effects of prunetin, one of the many flavonoid families, via the apoptotic mechanism. In addition, a glycoside called prunetin glucoside has been investigated for its anticancer effects through apoptotic mechanisms. The primary intention of this review is to identify the effects of prunetin and its glycoside, prunetin glucoside, on cell death signaling pathways in various cancers to enhance the potential anticancer effects of these natural compounds.

UBE2C promotes LUAD progression by ubiquitin-dependent degradation of p53 to inactivate the p53/p21 signaling pathway

Lung adenocarcinoma (LUAD) is one of the greatest causes of cancer death worldwide. As a novel potential tumor biomarker, ubiquitin-conjugating enzyme E2C (UBE2C) is a critical factor during the onset and development of human cancers. However, the mechanisms of UBE2C in LUAD are not well understood. In this study, increased expression level of UBE2C was observed in LUAD tumor tissues. High LUAD level portended a worse prognosis of LUAD patients. Down-regulation of UBE2C attenuated the cell proliferation and cycle, migration, and invasion. Consistently, the tumorigenic capacity of LUAD cells in nude mice was significantly suppressed by the knockdown of UBE2C. Knockdown of UBE2C inhibited the degradation of p53 protein via an ubiquitin-proteasome pathway, thereby increasing p53 and p21 protein expression. Moreover, the inhibition of LUAD cell malignant phenotypes caused by UBE2C knockdown was attenuated on account of the inactivation of p53/p21 signaling pathway. In conclusion, UBE2C facilitates cell malignant behaviour in LUAD by ubiquitin-dependent degradation of p53 to suppress the p53/p21 signaling pathway. UBE2C is potentially developed as a therapeutic target for patients with LUAD.

Establish a novel immune-related gene prognostic risk index (IRGPRI) associated with CD8+ cytotoxic T lymphocytes in non-small-cell lung cancer (NSCLC)

Background

The aim of this study is to create an index called IRGPRI (immune-related gene prognostic risk index) that can be utilized for predicting the prognosis and assessing the efficacy of immune checkpoint inhibitors (ICIs) therapy in patients with non-small-cell lung cancer (NSCLC).

Methods

Distinguishing gene expression patterns (DEGs) were detected in CD8+ cytotoxic T lymphocytes (CTLs) compared to other cellular types such as CD4 T cells, B cells, plasma cells, and CD8 Tex using the advanced technology of Single-cell RNA Sequencing (scRNA-seq). The construction of IRGPRI was accomplished by employing LASSO Cox regression analysis. We conducted a comparative analysis on clinical characteristics and molecular features, such as pathway enrichment and gene mutation, among the distinct subgroups of IRGPRI. Furthermore, we explored the correlation between immunological characteristics and IRGPRI subgroups to comprehensively assess the effectiveness of ICIs in NSCLC patients.

Results

A total of 109 genes were identified by intersecting immune-related genes with DEGs obtained from single-cell RNA sequencing data (GSE131907), specifically comparing CTLs to other cell types. From these, we selected 7 prognosis-related genes, namely TRBC1, HLA-DMA, CTSH, RAC1, CTSL, ANXA2, and CEBPB. These genes were used to construct the IRGPRI. The prognosis of patients diagnosed with NSCLC was found to be significantly better in the low-risk group compared to the high-risk group, as demonstrated by Kaplan-Meier (K-M) survival analysis. This observation was further confirmed through the utilization of data from the GEO cohort. The low-risk group demonstrated an increase in pathways linked with immune response, whereas the high-risk group exhibited a higher prevalence of pathways related to cancer. Furthermore, it was noted in the TCGA cohort that there existed a significant rise in the mutation frequency of every gene within the high-risk group as opposed to the low-risk group. Missense variation emerged as the most prevalent form of mutation. According to the analysis of immune cell infiltration and function, the comprehensive findings suggest that the group with a low risk is characterized by an increased presence of plasma cells, CTLs, T cells follicular helper, Tregs, and Dendritic cell resting. Additionally, they exhibit a higher score in terms of immune function for B cells, CD8+ T cells, checkpoint activity, T cell inhibition and stimulation. Moreover, this low-risk group demonstrates greater efficacy when treated with ICIs therapy compared to the high-risk group.

Conclusions

Our research effectively developed and verified a unique IRGPRI, showcasing its association with immune-related characteristics. As a result, the potential of IRGPRI as a valuable biomarker for predicting prognosis and evaluating the effectiveness of ICIs treatment in cancer is evident.

The role of p53 in male infertility

The tumor suppressor p53 is a transcription factor involved in a variety of crucial cellular functions, including cell cycle arrest, DNA repair and apoptosis. Still, a growing number of studies indicate that p53 plays multiple roles in spermatogenesis, as well as in the occurrence and development of male infertility. The representative functions of p53 in spermatogenesis include the proliferation of spermatogonial stem cells (SSCs), spermatogonial differentiation, spontaneous apoptosis, and DNA damage repair. p53 is involved in various male infertility-related diseases. Innovative therapeutic strategies targeting p53 have emerged in recent years. This review focuses on the role of p53 in spermatogenesis and male infertility and analyses the possible underlying mechanism involved. All these conclusions may provide a new perspective on drug intervention targeting p53 for male infertility treatment.

CircUGP2 Suppresses Intrahepatic Cholangiocarcinoma Progression via p53 Signaling Through Interacting With PURB to Regulate ADGRB1 Transcription and Sponging miR-3191-5p

Intrahepatic cholangiocarcinoma (ICC) is the second most common primary liver cancer and its prognosis remains poor. Although growing numbers of studies have verified the involvement of circular RNAs (circRNAs) in various cancer types, their specific functions in ICC remain elusive. Herein, a circRNA, circUGP2 is identified by circRNA sequencing, which is downregulated in ICC tissues and correlated with patients' prognosis. Moreover, circUGP2 overexpression suppresses tumor progression in vitro and in vivo. Mechanistically, circUGP2 functions as a transcriptional co-activator of PURB over the expression of ADGRB1. It can also upregulate ADGRB1 expression by sponging miR-3191-5p. As a result, ADGRB1 prevents MDM2-mediated p53 polyubiquitination and thereby activates p53 signaling to inhibit ICC progression. Based on these findings, circUGP2 plasmid is encapsulated into a lipid nanoparticle (LNP) system, which has successfully targeted tumor site and shows superior anti-tumor effects. In summary, the present study has identified the role of circUGP2 as a tumor suppressor in ICC through regulating ADGRB1/p53 axis, and the application of LNP provides a promising translational strategy for ICC treatment.

Mutant P53 modulation by cryptolepine through cell cycle arrest and apoptosis in triple negative breast cancer

BACKGROUND

Triple Negative Breast cancer is an aggressive breast cancer subtype. It has a more aggressive clinical course, an earlier age of onset, a larger propensity for metastasis, and worse clinical outcomes as evidenced by a higher risk of recurrence and a shorter survival rate. Currently, the primary options for TNBC treatment are surgery, radiation, and chemotherapy. These treatments however remain ineffective due to recurrence. However, given that p53 mutations have been identified in more than 60-88 % of TNBC, translating p53 into the clinical situation is particularly important in TNBC. In this study, we screened and evaluated the therapeutic potential of cryptolepine (CRP) in TNBC in-vitro models being an anti-malarial drug it could be repurposed as an anti-cancer therapeutic targeting TNBC. Moreover, the cytotoxicity activity of cryptolepine to TNBC cells and a detailed anti-tumor mechanism in mutant P53 has not been reported before.

METHODS

MTT assays were used to examine the cytotoxicity and cell viability activity of Cryptolepine in TNBC, non-TNBC T47D and MCF-7 and non-malignant MCF10A cells. Scratch wound and clonogenic assay was used to evaluate the cryptolepine's effect on migration and colony forming ability of TNBC cells. Flow cytometry, MMP and DAPI was used to assess cell cycle arrest and cell apoptosis mechanism. The expression of proteins was detected by western blots. The differential expression of RNAs was evaluated by RT-PCR and the interaction between P53 and drug was evaluated computationally using in-silico approach and in-vitro using ChIP assay.

RESULTS

In this study, we found that cryptolepine has more preferential cytotoxicity in TNBC than non-TNBC cells. Notably, our studies revealed the mechanism by which cryptolepine induces intrinsic apoptosis and inhibit migration, colony formation ability, induce cell cycle arrest by inducing conformational change in the mutant P53 thereby increasing its DNA binding ability, hence activating its tumor suppressing potential significantly.

CONCLUSION

Our study revealed that CRP significantly reduced the proliferation, migration and colony forming ability of TNBC cells lines. Moreover, it was revealed that CRP induces cell cycle arrest and apoptosis by activating mutant P53 and enhancing its DNA binding ability to induce its tumor suppressing ability.

An 8-aminoquinoline-naphthyl copper complex causes apoptotic cell death by modulating the expression of apoptotic regulatory proteins in breast cancer cells

Breast cancer is one of the most common cancers globally and a leading cause of cancer-related deaths among women. Despite the combination of chemotherapy with targeted therapy, including monoclonal antibodies and kinase inhibitors, drug resistance and treatment failure remain a common occurrence. Copper, complexed to various organic ligands, has gained attention as potential chemotherapeutic agents due to its perceived decreased toxicity to normal cells. The cytotoxic efficacy and the mechanism of cell death of an 8-aminoquinoline-naphthyl copper complex (Cu8AqN) in MCF-7 and MDA-MB-231 breast cancer cell lines was investigated. The complex inhibited the growth of MCF-7 and MDA-MB-231 cells with IC50 values of 2.54 ± 0.69 μM and 3.31 ± 0.06 μM, respectively. Nuclear fragmentation, annexin V binding, and increased caspase-3/7 activity indicated apoptotic cell death. The loss of mitochondrial membrane potential, an increase in caspase-9 activity, the absence of active caspase-8 and a decrease of tumour necrosis factor receptor 1(TNFR1) expression supported activation of the intrinsic apoptotic pathway. Increased ROS formation and increased expression of haem oxygenase-1 (HMOX-1) indicated activation of cellular stress pathways. Expression of p21 protein in the nuclei was increased indicating cell cycle arrest, whilst the expression of inhibitor of apoptosis proteins (IAPs); cIAP1, XIAP and survivin were decreased, creating a pro-apoptotic environment. Phosphorylated p53 species; phospho-p53(S15), phospho-p53(S46), and phospho-p53(S392) accumulated in MCF-7 cells indicating the potential of Cu8AqN to restore p53 function in the cells. In combination, the data indicates that Cu8AqN is a useful lead molecule worthy of further exploration as a potential anti-cancer drug.

p53 lysine-lactylated modification contributes to lipopolysaccharide-induced proinflammatory activation in BV2 cell under hypoxic conditions

p53 has diversity functions in regulation of transcription, cell proliferation, cancer metastasis, etc. Recent studies have shown that p53 and nuclear factor-κB (NF-κB) co-regulate proinflammatory responses in macrophages. However, the role of p53 lysine lactylation (p53Kla) in mediating proinflammatory phenotypes in microglia under hypoxic conditions remains unclear. In the current study, we investigated the proinflammatory activation exacerbated by hypoxia and the levels of p53Kla in microglial cells. BV2 cells, an immortalized mouse microglia cell line, were divided into control, lipopolysaccharide (LPS)-induced, hypoxia (Hy), and LPS-Hy groups. The protein expression levels of p53 and p53Kla and the activation of microglia were compared among the four groups. Sodium oxamate and mutant p53 plasmids were transfected into BV2 cells to detect the effect of p53Kla on microglial proinflammatory activation. LPS-Hy stimulation significantly upregulated p53Kla levels in both the nucleus and the cytoplasm of BV2 cells. In contrast, the p53 protein levels were downregulated. LPS-Hy stimulation upregulated phosphorylated p65 protein levels in nuclear and activated the NF-κB pathway in BV2 cells, resulting in increased expression of pro-inflammatory cytokines (iNOS, IL6, IL1β, TNFα), enhanced cell viability, and concomitantly, increased cytotoxicity. In conclusion, p53 lysine-lactylated modification contributes to LPS-induced proinflammatory activation in BV2 cells under hypoxia through NF-κB pathway and inhibition of lactate production may alleviate neuroinflammatory injury.

Evaluating targeted therapies in older patients with TP53-mutated AML

Mutation of thetumor suppressor gene, TP53 (tumor protein 53), occurs in up to 15% of all patients with acute myeloid leukemia (AML) and is enriched within specific clinical subsets, most notably in older adults, and including secondary AML cases arising from preceding myeloproliferative neoplasm (MPN), myelodysplastic syndrome (MDS), patients exposed to prior DNA-damaging, cytotoxic therapies. In all cases, these tumors have remained difficult to effectively treat with conventional therapeutic regimens. Newer approaches fortreatmentofTP53-mutated AML have shifted to interventions that maymodulateTP53 function, target downstream molecular vulnerabilities, target non-p53 dependent molecular pathways, and/or elicit immunogenic responses. This review will describe the basic biology of TP53, the clinical and biological patterns of TP53 within myeloid neoplasms with a focus on elderly AML patients and will summarize newer therapeutic strategies and current clinical trials.

From Crypts to Cancer: A Holistic Perspective on Colorectal Carcinogenesis and Therapeutic Strategies

Colorectal cancer (CRC) represents a significant global health burden, with high incidence and mortality rates worldwide. Recent progress in research highlights the distinct clinical and molecular characteristics of colon versus rectal cancers, underscoring tumor location's importance in treatment approaches. This article provides a comprehensive review of our current understanding of CRC epidemiology, risk factors, molecular pathogenesis, and management strategies. We also present the intricate cellular architecture of colonic crypts and their roles in intestinal homeostasis. Colorectal carcinogenesis multistep processes are also described, covering the conventional adenoma-carcinoma sequence, alternative serrated pathways, and the influential Vogelstein model, which proposes sequential APC, KRAS, and TP53 alterations as drivers. The consensus molecular CRC subtypes (CMS1-CMS4) are examined, shedding light on disease heterogeneity and personalized therapy implications.

CEP-1347 Boosts Chk2-Mediated p53 Activation by Ionizing Radiation to Inhibit the Growth of Malignant Brain Tumor Cells

Radiation therapy continues to be the cornerstone treatment for malignant brain tumors, the majority of which express wild-type p53. Therefore, the identification of drugs that promote the ionizing radiation (IR)-induced activation of p53 is expected to increase the efficacy of radiation therapy for these tumors. The growth inhibitory effects of CEP-1347, a known inhibitor of MDM4 expression, on malignant brain tumor cell lines expressing wild-type p53 were examined, alone or in combination with IR, by dye exclusion and/or colony formation assays. The effects of CEP-1347 on the p53 pathway, alone or in combination with IR, were examined by RT-PCR and Western blot analyses. The combination of CEP-1347 and IR activated p53 in malignant brain tumor cells and inhibited their growth more effectively than either alone. Mechanistically, CEP-1347 and IR each reduced MDM4 expression, while their combination did not result in further decreases. CEP-1347 promoted IR-induced Chk2 phosphorylation and increased p53 expression in concert with IR in a Chk2-dependent manner. The present results show, for the first time, that CEP-1347 is capable of promoting Chk2-mediated p53 activation by IR in addition to inhibiting the expression of MDM4 and, thus, CEP-1347 has potential as a radiosensitizer for malignant brain tumors expressing wild-type p53.

Assessment of the Circulating PD-1 and PD-L1 Levels and P53 Expression as a Predictor of Relapse in Pediatric Patients with Wilms Tumor and Hypernephroma

Background/Objectives: Wilms tumor (WT) is the most common form of pediatric renal tumor, accounting for over 90% of cases followed by hypernephroma. Some pediatric patients with WT (10%) experience relapse or metastasis and have poor survival rates. PD-L1 assists cancer cells in escaping damage from the immune system. P53 mutations are found in relapsed WT tumor samples. We hypothesized that testing circulating PD-1 and PD-L1 and P53 expression levels could offer a simple method to predict patient relapse and explore novel treatments for pediatric WTs and hypernephroma. Methods: Flow cytometric detection of cPD-1, cPD-L1, and P53 expression in relapsed and in-remission WT and hypernephroma before and after one year of chemotherapy was performed. Results: Our data shows increased levels of cPD-L1 in relapsed pediatric patients with WT or hypernephroma before and after chemotherapy. There were also slight and significant increases in cPD-1 levels in relapsed groups before chemotherapy. Additionally, we observed significant decreases in P53 expression after one year of chemotherapy in relapsed pediatric patients. Conclusions: Our study found that circulating PD-L1 can be used as a predictor marker for WT and hypernephroma relapse. In conclusion, these circulating markers can assist in monitoring relapse in WT and hypernephroma patients without the need for several biopsies.

Identification of Scutebarbatine B metabolites in rats using UHPLC-Q-Orbitrap-MS/MS and exploration of its mechanism of reversal multidrug resistance in breast cancer by network pharmacology and molecular docking studies

Scutebarbatine B (SBT-B) is a neo-clerodane diterpenic compound isolated from Scutellaria barbata D. Don (S. barbata), which has been reported to exhibit inhibitory P-glycoprotein (P-gp) property in MCF-7/ADR cells. However, its metabolism and molecular mechanism of reversal multidrug resistance (MDR) in breast cancer remains unclear. This study investigated the metabolite profile of SBT-B in rats by UHPLC-Q-Orbitrap-MS/MS, and explored its mechanism of reversal MDR through network pharmacology and molecular docking studies. A total of 16 Phase I metabolites and 2 Phase II metabolites were identified, and 18 metabolites were all newly discovered metabolites as novel compounds. The metabolic pathway of SBT-B mainly includes oxidization, reduction, hydrolysis, acetylation and glycination. Meanwhile, network pharmacology analyses showed that SBT-B mainly regulated p27 phosphorylation during cell cycle progression, p53 signaling pathway, influence of Ras and Rho proteins on G1 to S Transition. Molecular docking studies revealed that SBT-B exhibits the potential to inhibit P-gp expression by selectively binding to GLN721 and ALA981 residue sites at the interface of P-gp. In addition, SBT-B exhibits moderate binding affinity with CDK2 and E2F1. This study illustrated the major metabolic pathways of SBT-B in vivo, clarified detailed information on SBT-B metabolites in rats, and uncovered the potential mechanism of SBT-B reversal MDR in breast cancer, providing new insights for the development of P-gp inhibitors.

Targeting mutant p53 with arsenic trioxide: A preclinical study focusing on triple negative breast cancer

New treatments are urgently required for triple-negative breast cancer (TNBC). As TP53 is mutated in approximately 80% of TNBC, it is theoretically an attractive target for new drugs for this disease. Arsenic trioxide (ATO), which is used to treat promyelocytic leukaemia, was recently shown to reactivate mutant p53 and restore wild-type functionality. The aim of this study was to evaluate ATO as a potential new treatment for TNBC. Using a panel of 20 cell lines, we found that TNBC cell lines were more sensitive to ATO than non-TNBC cell lines (P = 0.045). Consistent with its ability to reactivate mutant p53, ATO was a more potent inhibitor of proliferation in cell lines with mutant TP53 than the wildtype TP53 (P = 0.027). Direct evidence of mutant p53 reactivation was the induction of multiple wild-type p53 canonical target genes such as CDKN1A, SLC7A11, BBC3, PMAIP1, SESN2, SRXN1 and TXNRD1. Our findings support the activation of mutant p53 by ATO and, furthermore, the possible repurposing of ATO to treat TP53-mutated TNBC.

Molecular Characterization and Xenotransplantation of Pancreatic Cancer Using Endoscopic Ultrasound-Guided Fine Needle Aspiration (EUS-FNA)

Pancreatic cancer has one of the worst prognoses among all malignancies and few available treatment options. Patient-derived xenografts can be used to develop personalized therapy for pancreatic cancer. Endoscopic ultrasound fine-needle aspiration (EUS-FNA) may provide a powerful alternative to surgery for obtaining sufficient tissue for the establishment of patient-derived xenografts. In this study, EUS-FNA samples were obtained for 30 patients referred to the Ottawa Hospital, Ottawa, Ontario, Canada. These samples were used for xenotransplantation in NOD-SCID mice and for genetic analyses. The gene expression of pancreatic-cancer-relevant genes in xenograft tumors was examined by immunohistochemistry. Targeted sequencing of both the patient-derived tumors and xenograft tumors was performed. The xenografts' susceptibility to oncolytic virus infection was studied by infecting xenograft-derived cells with VSV∆51-GFP. The xenograft take rate was found to be 75.9% for passage 1 and 100% for passage 2. Eighty percent of patient tumor samples were successfully sequenced to a high depth for 42 cancer genes. Xenograft histological characteristics and marker expression were maintained between passages. All tested xenograft samples were susceptible to oncoviral infection. We found that EUS-FNA is an accessible, minimally invasive technique that can be used to acquire adequate pancreatic cancer tissue for the generation of patient-derived xenografts and for genetic sequencing.

Enhanced Lung Cancer Detection Using a Combined Ratio of Antigen-Autoantibody Immune Complexes against CYFRA 21-1 and p53

The early detection of lung cancer (LC) improves patient outcomes, but current methods have limitations. Autoantibodies against tumor-associated antigens have potential as early biomarkers. This study evaluated the 9G testTM Cancer/Lung, measuring circulating complexes of two antigen-autoantibody immune complexes (AIC) against their respective free antigens (CYFRA 21-1 and p53) for LC diagnosis. We analyzed 100 LC patients and 119 healthy controls using the 9G testTM Cancer/Lung, quantifying the levels of AICs (CYFRA 21-1-Anti-CYFRA 21-1 autoantibody immune complex (CIC) and p53-Anti-p53 autoantibody immune complex (PIC)), free antigens (CYFRA 21-1 and p53), and ratios of AICs/antigens (LC index). The levels of the CICs and PICs were significantly elevated in LC compared to the controls (p < 0.0062 and p < 0.0026), while free antigens showed no significant difference. The CIC/CYFRA 21-1 and PIC/p53 ratios were also significantly higher in LC (all, p < 0.0001). The LC index, when combining both ratios, exhibited the best diagnostic performance with an area under the curve (AUC) of 0.945, exceeding individual CICs, PICs, and free antigens (AUCs ≤ 0.887). At a cut-off of 3.60, the LC index achieved 81% sensitivity and 95% specificity for LC diagnosis. It detected early-stage (Stage I-II) LC with 87.5% sensitivity, exceeding its performance in advanced stages (72.7%). The LC index showed no significant differences based on age, gender, smoking status (former, current, or never smoker), or pack years smoked. The LC index demonstrates promising potential for early LC diagnosis, exceeding conventional free antigen markers.

Pancreatic cancer organoid-screening captures personalized sensitivity and chemoresistance suppression upon cytochrome P450 3A5-targeted inhibition

Cytochrome P450 3A5 (CYP3A5) has been proposed as a predictor of therapy response in subtypes of pancreatic ductal adenocarcinoma cancer (PDAC). To validate CYP3A5 as a therapeutic target, we developed a high-content image organoid-based screen to quantify the phenotypic responses to the selective inhibition of CYP3A5 enzymatic activity by clobetasol propionate (CBZ), using a cohort of PDAC-derived organoids (PDACOs). The chemoresistance of PDACOs to a panel of standard-of-care drugs, alone or in combination with CBZ, was investigated. PDACO pharmaco-profiling revealed CBZ to have anti-cancer activity that was dependent on the CYP3A5 level. In addition, CBZ restored chemo-vulnerability to cisplatin in a subset of PDACOs. A correlative proteomic analysis established that CBZ caused the suppression of multiple cancer pathways sustained by or associated with a mutant form of p53. Limiting the active pool of CYP3A5 enables targeted and personalized therapy to suppress pro-oncogenic mechanisms that fuel chemoresistance in some PDAC tumors.

Progress in deciphering the role of p53 in diffuse large B-cell lymphoma: mechanisms and therapeutic targets

Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma subtype, accounting for 30%-40% of non-Hodgkin lymphoma in adults. The mechanisms underlying DLBCL occurrence are extremely complex, and involve the B-cell receptor (BCR) and Toll-like receptor (TLR) signaling pathways, as well as genetic abnormalities and other factors. With the development of high-throughput sequencing, an increasing number of abnormal genes have been identified in DLBCL. Among them, the tumor protein p53 (TP53/p53) gene is important in DLBCL occurrence. Patients with DLBCL carrying TP53 gene abnormalities generally have poor prognosis and studies of p53 have potential to provide a better basis for their treatment. Normally, p53 is maintained at low levels through its interaction with murine double minute 2 (MDM2), and prevents tumorigenesis by mediating cell cycle arrest, apoptosis, and repair of damaged cells, among other processes. Therefore, the prognosis of patients with DLBCL harboring TP53 gene abnormalities (mutations, deletions, etc.) is poor, and targeting p53 for tumor therapy has become a research hotspot, following developments in molecular biology technologies. Current treatments targeting p53 mainly act by restoring the function or promoting degradation of mutant p53, and enhancing wild-type p53 protein stability and activity. Based on the current status of p53 research, exploration of existing therapeutic methods to improve the prognosis of patients with DLBCL with TP53 abnormalities is warranted.

DNA methylation profile of inflammatory breast cancer and its impact on prognosis and outcome

BACKGROUND

Inflammatory breast cancer (IBC) is a rare disease characterized by rapid progression, early metastasis, and a high mortality rate.

METHODS

Genome-wide DNA methylation analysis (EPIC BeadChip platform, Illumina) and somatic gene variants (105 cancer-related genes) were performed in 24 IBCs selected from a cohort of 140 cases.

RESULTS

We identified 46,908 DMPs (differentially methylated positions) (66% hypomethylated); CpG islands were predominantly hypermethylated (39.9%). Unsupervised clustering analysis revealed three clusters of DMPs characterized by an enrichment of specific gene mutations and hormone receptor status. The comparison among DNA methylation findings and external datasets (TCGA-BRCA stages III-IV) resulted in 385 shared DMPs mapped in 333 genes (264 hypermethylated). 151 DMPs were associated with 110 genes previously detected as differentially expressed in IBC (GSE45581), and 68 DMPs were negatively correlated with gene expression. We also identified 4369 DMRs (differentially methylated regions) mapped on known genes (2392 hypomethylated). BCAT1, CXCL12, and TBX15 loci were selected and evaluated by bisulfite pyrosequencing in 31 IBC samples. BCAT1 and TBX15 had higher methylation levels in triple-negative compared to non-triple-negative, while CXCL12 had lower methylation levels in triple-negative than non-triple-negative IBC cases. TBX15 methylation level was associated with obesity.

CONCLUSIONS

Our findings revealed a heterogeneous DNA methylation profile with potentially functional DMPs and DMRs. The DNA methylation data provided valuable insights for prognostic stratification and therapy selection to improve patient outcomes.

Phase 1 dose escalation study of the MDM2 inhibitor milademetan as monotherapy and in combination with azacitidine in patients with myeloid malignancies

BACKGROUND

Mouse double minute-2 homolog (MDM2) plays a key role in downregulating p53 activity in hematologic malignancies, and its overexpression is associated with poor outcomes.

METHODS

This phase 1 study assessed the safety and efficacy of different dosing regimens of the MDM2 inhibitor milademetan as monotherapy and in combination with azacitidine (AZA) in patients with relapsed or refractory acute myeloid leukemia or high-risk myelodysplastic syndromes.

RESULTS

Seventy-four patients (monotherapy, n = 57; milademetan-AZA combination, n = 17) were treated. The maximum tolerated dose of milademetan was 160 mg once daily given for the first 14-21 days of 28-day cycles as monotherapy and on Days 5-14 in combination with AZA. Dose-limiting toxicities were gastrointestinal, fatigue, or renal/electrolyte abnormalities. Treatment-emergent adverse events related to milademetan occurred in 82.5% and 64.7% of participants in the monotherapy and AZA combination arms, respectively. Two participants (4.2%) in the monotherapy arm achieved complete remission (CR), and 1 (2.1%) achieved CR with incomplete blood count recovery (CRi). Two participants (13.3%) achieved CRi in the combination arm. New TP53 mutations, detected only during milademetan monotherapy, were found pre-existing below standard detection frequency by droplet digital polymerase chain reaction.

INTERPRETATION

Milademetan was relatively well tolerated in this population; however, despite signals of activity, clinical efficacy was minimal.