A small bowel adenocarcinoma harboring a DDR2 mutation in a celiac patient.

We present the case of a 62-year-old man with a history of celiac disease and IgA deficiency, following a strict gluten-free diet that was admitted to our hospital for recurrent abdominal pain, fatigue and melena. Esophagogastroduodenoscopy and colonoscopy with biopsies were normal. A video-capsule endoscopy was performed and revealed a sub-stenosing, vegetating, and bleeding lesion in the first jejunal loop. He underwent laparotomic surgery with resection of the involved segment with loco-regional lymphadenectomy. The pathological report described a poorly differentiated adenocarcinoma of the jejunum, stage IIIA (pT3pN1). Analysis of next-generation sequencing (NGS) of DNA on the surgical sample revealed a likely pathogenetic variant in exon 15 of the DDR2 gene (c.2003G > A) and a TP53 non-frame-shift deletion (c.585_602del). Considering the risk of recurrence, he was candidate to 6 months of adjuvant chemotherapy with platinum salt and fluoropyrimidine. Thirty-eight months after the diagnosis, the patient is still disease free and in good clinical condition. This is the first described case of SBA with DDR2 mutation. Considering the limited therapeutic options beyond surgery for SBA, molecular analyses could become promising for the search for potential targetable alterations for treatments with new available drugs.

Association of TP53 Mutation Status and Sex with Clinical Outcome in NSCLC Treated with Immune Checkpoint Inhibitors: A Retrospective Cohort Study.

Purpose: Some studies suggest that TP53 mutations are associated with the response to immune checkpoint inhibitors (ICI) in patients with non-small cell lung cancer (NSCLC) and also contribute to sex disparities in several cancers. Thus, we hypothesized that TP53 mutations might serve as sex-dependent genomic biomarkers of ICI treatment response in patients with NSCLC. Materials and Methods: Clinical data of 100 patients with metastatic NSCLC treated with ICI monotherapy at Seoul National University Bundang Hospital (SNUBH) were retrospectively reviewed. Genomic and clinical datasets of TCGA and an ICI-treated lung cancer cohort (cBioPortal) were also analyzed. Results: In SNUBH cohort, no statistically significant difference was observed in disease control rate per the TP53 mutation status (p=0.503); however, female patients with TP53 mutated (MT) had a significantly prolonged median progression-free survival (PFS) compared to wild-type (WT) (6.1 months in TP53 MT vs. 2.6 months in TP53 WT; p=0.021). PD-L1 high (≥50%) expression was significantly enriched in female patients with TP53 MT (p=0.001). The analysis from publicly available dataset also revealed that females with NSCLC with TP53 MT showed significantly longer PFS than those with TP53 WT (p<0.001). In TCGA analysis, expression of immune-related genes, and TMB score in TP53 MT females were higher than in males without TP53 MT. Conclusion: Female patients with NSCLC with TP53 mutations had high PD-L1 expression and showed favorable clinical outcomes following ICI therapy, suggesting a need for further research to explore the role of TP53 mutations for sex disparities in response to ICI therapy.

Insights into gemcitabine resistance in pancreatic cancer: association with metabolic reprogramming and TP53 pathogenicity in patient derived xenografts.

BACKGROUND: With poor prognosis and high mortality, pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies. Standard of care therapies for PDAC have included gemcitabine for the past three decades, although resistance often develops within weeks of chemotherapy initiation through an array of possible mechanisms. METHODS: We reanalyzed publicly available RNA-seq gene expression profiles of 28 PDAC patient-derived xenograft (PDX) models before and after a 21-day gemcitabine treatment using our validated analysis pipeline to identify molecular markers of intrinsic and acquired resistance. RESULTS: Using normalized RNA-seq quantification measurements, we first identified oxidative phosphorylation and interferon alpha pathways as the two most enriched cancer hallmark gene sets in the baseline gene expression profile associated with intrinsic gemcitabine resistance and sensitivity, respectively. Furthermore, we discovered strong correlations between drug-induced expression changes in glycolysis and oxidative phosphorylation genes and response to gemcitabine, which suggests that these pathways may be associated with acquired gemcitabine resistance mechanisms. Thus, we developed prediction models using baseline gene expression profiles in those pathways and validated them in another dataset of 12 PDAC models from Novartis. We also developed prediction models based on drug-induced expression changes in genes from the Molecular Signatures Database (MSigDB)'s curated 50 cancer hallmark gene sets. Finally, pathogenic TP53 mutations correlated with treatment resistance. CONCLUSION: Our results demonstrate that concurrent upregulation of both glycolysis and oxidative phosphorylation pathways occurs in vivo in PDAC PDXs following gemcitabine treatment and that pathogenic TP53 status had association with gemcitabine resistance in these models. Our findings may elucidate the molecular basis for gemcitabine resistance and provide insights for effective drug combination in PDAC chemotherapy.

Harnessing the TP53INP1/TP53I3 axis for inhibition of colorectal cancer cell proliferation through MEG3 and Linc-ROR Co-expression.

Dysregulation of long noncoding RNAs (lncRNAs), such as maternally expressed gene 3 (MEG3) and long intergenic noncoding RNA regulator of reprogramming (linc-ROR), plays a crucial role in colorectal cancer progression. We aimed to assess linc-ROR silencing and MEG3 activation on the colorectal cancer cell proliferation simultaneously; and explore the underlying mechanisms in the TP53-associated Pathway. The MEG3 and linc-ROR shRNA were cloned under the bidirectional CEA promoter (UM1). Subsequently, additional vectors were constructed to express linc-ROR shRNA (UM2) and MEG3 (UM3). After transfecting colorectal cancer cell lines with these recombinant vectors, experiments on cell viability, apoptosis, and cell cycle analysis were conducted. Furthermore, TP53's transcriptional activity and associated genes were assessed using quantitative real-time polymerase chain reaction (qRT-PCR). Interestingly, UM1 significantly inhibited the proliferation of both cell lines than UM2 and UM3. In response to UM1, TP53 transcript remarkably increased in HCT116 cells (10.46) than SW480 cells (6.16); which resulted in up-regulation of TP53INP1, TP53I3, GDF15, CCKN1A and BAX, and down-regulation of G1 cyclins (D1, E1). The rate of apoptosis increased in HCT116 (36.35 %) and SW480 (16.64 %) cells than control. Moreover, UM1-transfected HCT116 cells exhibited a notable arrest in the G0/G1 phase, accompanied by a reduction in the G2/M cell population. Compared to unidirectional vectors, the concurrent targeting approach enhanced TP53 activation at the transcription level. The cell response to UM1 resulted in rapid upregulation of TP53, leading to inhibition of cell proliferation, increased apoptosis, and cell cycle arrest. These findings suggest that the synergistic effect of targeting both MEG3 and linc-ROR could serve as a promising therapeutic strategy for TP53-associated colon cancer.

Immune landscape of hepatocellular carcinoma: The central role of TP53-inducible glycolysis and apoptosis regulator.

Objective: This study aims to address the substantive issue of lacking reliable prognostic biomarkers in hepatocellular carcinoma (HCC) by investigating the relationship between TP53-inducible glycolysis and apoptosis regulator (TIGAR) and HCC prognosis using The Cancer Genome Atlas database. Methods: (1) Integrated statistical analyses, including logistic regression, Wilcoxon signed-rank test, and Kruskal-Wallis test, were conducted to explore the association between TIGAR expression and clinical-pathological features of HCC. (2) The Kaplan-Meier method combined with univariate and multivariate Cox regression models underscored TIGAR as a prognostic factor in HCC. (3) Gene set enrichment analysis (GSEA) revealed key pathways associated with TIGAR, while single-sample gene set enrichment analysis (ssGSEA) determined its relevance to cancer immune infiltration. Results: (1) Elevated TIGAR expression was significantly correlated with decreased survival outcomes in HCC patients. (2) GSEA highlighted the significant link between TIGAR and humoral immunity. (3) ssGSEA revealed a positive correlation between TIGAR expression and infiltration of Th1 and Th2 cells and a negative correlation with Th17 cell infiltration. Conclusion: TIGAR, as a potential prognostic biomarker for HCC, holds significant value in immune infiltration. Understanding the role of TIGAR could contribute to improved prognostic predictions and personalized treatment strategies for HCC patients.

Impact of TP53 mutations on brain metastasis control in non-small cell lung cancer patients undergoing stereotactic radiosurgery.

Purpose: To investigate whether TP53 variants may be correlated with overall survival and local control following stereotactic radiosurgery (SRS) for brain metastases (BMs) from non-small cell lung cancer (NSCLC). Methods: Patients undergoing an initial course of SRS for NSCLC brain metastases between 1/2015 and 12/2020 were retrospectively identified. Overall survival and freedom from local intracranial progression (FFLIP) were estimated via Kaplan-Meier method. Cox models assessed TP53 variant status (pathogenic variant, PV; variant not detected, ND). Results: 255 patients underwent molecular profiling for TP53, among whom 144 (56%) had a TP53 PV. Median follow-up was 11.6 months. OS was not significantly different across TP53 status. A trend toward superior FFLIP was observed for PV (95% CI 62.9 months-NR) versus ND patients (95% CI 29.4 months-NR; p=0.06). Superior FFLIP was observed for patients with one TP53 variant versus those with TP53 ND. Conclusion: Among NSCLC patients with BMs, the potential association between TP53 status and post-SRS FFLIP warrants further investigation in a larger prospective cohort.

Clinicopathological and genetic characterization of radiotherapy-induced undifferentiated pleomorphic sarcoma following breast cancer: a case series of three tumors and comprehensive literature review.

AIMS: Compared to primary breast sarcoma (BSs), radiotherapy-induced sarcoma (RIS) is a less frequent type of secondary breast sarcoma. Undifferentiated pleomorphic sarcoma (UPS) is an even rarer occurrence within the RIS category. This study aimed to present the clinicopathologic and molecular features of breast radiotherapy-induced UPS. METHODS: A retrospective study was conducted at the Third Affiliated Hospital of Soochow University to analyze three patients with radiation-induced undifferentiated pleomorphic sarcoma (UPS) following breast cancer, spanning from 2006 to 2023. The clinical and pathological variables were extracted from the medical records, while immunohistochemistry was employed to analyze the immunophenotypes of these tumors. Genomic characteristics were assessed through DNA and RNA sequencing techniques. Another 15 cases from the literature were also reviewed to better characterize the tumor. RESULTS: The affected areas encompass the chest wall and breasts, with an incubation period ranging from 6 to 17 years. The tumor cells exhibit pleomorphism and demonstrate a high degree of pathological mitosis. Notably, two cases displayed an accelerated disease progression, characterized by recurrent tumors and metastases occurring within short intervals of 48 and 7 months respectively subsequent to the initial diagnosis. The two prevailing identified genes were TP53 (2/3, 66.7%) and RB1 (1/3, 33.3%). Through analysis of somatic copy number variation (CNV), it was discovered that two oncogenes, MCL1 (1/3, 33.3%) and MYC (1/3, 33.3%), had experienced gains in CNV. The Tumor Mutational Burden (TMB) values for case 1, case 2, and case 3 were 5.9 mut/Mb, 1.0 mut/Mb, and 3.0 mut/Mb, respectively. Moreover, the analysis of RNA-NGS (next-generation sequencing) revealed the presence of a novel gene fusion, named COL3A1-GULP1, in case 2. CONCLUSIONS: Based on our thorough analysis of research findings and previous reports, it is evident that radiotherapy-induced UPS exhibits a highly diverse and frequently severe clinical and biological behavior. Identifying tumor formation using genome sequencing can help understand its biological behavior and determine personalized treatments.

A case report and literature review on TP53 gene mutation in a bladder rhabdomyosarcoma patient.

Background: Rhabdomyosarcoma of the bladder is an infrequent neoplastic condition characterized by a pronounced malignant situation with challenges in treatment due to the lack of standardized guidelines and large-scale of clinical studies. The patient in this case is tested TP53 mutation that may provide new diagnostic and therapeutic options. Case presentation: Here, we reported a 34-year-old male who received bladder tumor resection, and diagnosed as bladder rhabdomyosarcoma with TP53 mutation after the pathology test. This patient underwent 6 rounds of chemotherapy. However, the pelvic tumor recurred 11 months after the first surgery. So, the patient accepted the pelvic tumor resection. Only 3 months after the surgical intervention, the patient underwent abdominal massive metastasis and ultimately succumbed to the illness six months following the second surgery. The course of the illness was 22 months. Conclusion: Bladder rhabdomyosarcoma is a disease with an extremely poor prognosis. Genetic testing holds significant value in the diagnosis and treatment. Perhaps targeted therapy against TP53 is potential valuable for such rare diseases.

The immunomodulatory effects of cannabidiol on Hsp70-activated NK cells and tumor target cells.

BACKGROUND: Cannabidiol (CBD), the major non-psychoactive component of cannabis, exhibits anti-inflammatory properties, but less is known about the immunomodulatory potential of CBD on activated natural killer (NK) cells and/or their targets. Many tumor cells present heat shock protein 70 (Hsp70) on their cell surface in a tumor-specific manner and although a membrane Hsp70 (mHsp70) positive phenotype serves as a target for Hsp70-activated NK cells, a high mHsp70 expression is associated with tumor aggressiveness. This study investigated the immuno-modulatory potential of CBD on NK cells stimulated with TKD Hsp70 peptide and IL-2 (TKD+IL-2) and also on HCT116 p53wt and HCT116 p53-/- colorectal cancer cells exhibiting high and low basal levels of mHsp70 expression. RESULTS: Apart from an increase in the density of NTB-A and a reduced expression of LAMP-1, the expression of all other activatory NK cell receptors including NKp30, NKG2D and CD69 which are significantly up-regulated after stimulation with TKD+IL-2 remained unaffected after a co-treatment with CBD. However, the release of major pro-inflammatory cytokines by NK cells such as interferon-γ (IFN-γ) and the effector molecule granzyme B (GrzB) was significantly reduced upon CBD treatment. With respect to the tumor target cells, CBD significantly reduced the elevated expression of mHsp70 but had no effect on the low basal mHsp70 expression. Expression of other NK cell ligands such as MICA and MICB remained unaffected, and the NK cell ligands ULBP and B7-H6 were not expressed on these target cells. Consistent with the reduced mHsp70 expression, treatment of both effector and target cells with CBD reduced the killing of high mHsp70 expressing tumor cells by TKD+IL-2+CBD pre-treated NK cells but had no effect on the killing of low mHsp70 expressing tumor cells. Concomitantly, CBD treatment reduced the TKD+IL-2 induced increased release of IFN-γ, IL-4, TNF-α and GrzB, but CBD had no effect on the release of IFN-α when NK cells were co-incubated with tumor target cells. CONCLUSION: Cannabidiol (CBD) may potentially diminish the anti-tumor effectiveness of TKD+IL-2 activated natural killer (NK) cells.

Variation characteristics and clinical significance of TP53 in patients with myeloid neoplasms.

Objectives: MDS and AML characterized by TP53 variations have a poor prognosis in general. However, specifically, differences in prognosis have also been observed in patients with different TP53 variants and VAFs.Methods: Here, we retrospectively analyzed datasets of patients with MDS, MPN, and AML who underwent targeted DNA sequencing from February 2018 to December 2023, and patients with reportable TP53 variations were screened. Demographic data and clinical data were collected, and the relationship between TP53 alterations and patient prognosis (AML/MDS) was analyzed using the cBioPortal and Kaplan-Meier Plotter databases. The relationship between the VAFs of TP53 variations and prognoses was analyzed using data from the present study.Results: Sixty-two variants of TP53 were identified in 58 patients. We mainly identified single mutations (79.31%, 46/58), followed by double (17.24%, 10/58) and triple (3.45%, 2/58) mutations. The variations were mainly enriched in exon4-exon8 of TP53. Missense (72.58%, 45/62) mutations were the main type of variations, followed by splice-site (9.68%, 6/62), nonsense (9.68%, 6/62), frameshift (6.45%, 4/62), and indel (1.61%, 1/62) mutations. In this study, p.Arg175His and p.Arg273His were high-frequency TP53 mutations, and DNMT3A and TET2 were commonly co-mutated genes in the three types of myeloid neoplasms; However, we reported some new TP53 variants in MPN that have not been found in the public database. Moreover, MDS or AML characterized by altered TP53 had a shorter OS than patients in the unaltered group (P<0.01), low TP53 mRNA levels were associated with shorter OS in patients with AML (P<0.01). Data from our center further found higher VAF (≥10%) associated with shorter OS in patients with MDS (median 2.75 vs. 24 months) (P<0.01).Conclusion: TP53 mutations are mainly enriched in exon4-exon8, are missense and single mutations in myeloid neoplasms, and are associated with poor prognosis of MDS/AML, and higher VAF (≥10%) of TP53 mutations associated with a shorter OS in patients with MDS.

[Endometrial carcinoma: molecular classification in routine pathology]. / Endometriumkarzinom: molekulare Klassifikation in der Routinepathologie.

The molecular classification of endometrial carcinoma defines four main groups: polymerase­É›(PolE) gene mutated, microsatellite unstable (MSI), p53 abnormal tumors and tumors with no specific molecular profile (NSMP). This classification provides significant insights into the prognosis and therapeutic decisions. Each group exhibits unique genetic profiles identified through immunohistochemistry and molecular diagnostics, enabling personalized treatment. The identification of these molecular signatures necessitates precise analytical methods, selected based on the local circumstances at each site. The approach to molecular classification highlights the critical role of pathology in the diagnosis and emphasizes the necessity of collaboration between the clinic and pathology.

Comprehensive analysis identifies ubiquitin ligase FBXO42 as a tumor-promoting factor in neuroblastoma.

Neuroblastoma, the deadliest solid tumor in children, exhibits alarming mortality rates, particularly among high-risk cases. To enhance survival rates, a more precise risk stratification for patients is imperative. Utilizing proteomic data from 34 cases with or without N-Myc amplification, we identified 28 differentially expressed ubiquitination-related proteins (URGs). From these, a prognostic signature comprising 6 URGs was constructed. A nomogram incorporating clinical-pathological parameters yielded impressive AUC values of 0.88, 0.93, and 0.95 at 1, 3, and 5 years, respectively. Functional experiments targeting the E3 ubiquitin ligase FBXO42, a component of the prognostic signature, revealed its TP53-dependent promotion of neuroblastoma cell proliferation. In conclusion, our ubiquitination-related prognostic model robustly predicts patient outcomes, guiding clinical decisions. Additionally, the newfound pro-proliferative role of FBXO42 offers a novel foundation for understanding the molecular mechanisms of neuroblastoma.

Comprehensive classification of TP53 somatic missense variants based on their impact on p53 structural stability.

Somatic variation is a major type of genetic variation contributing to human diseases including cancer. Of the vast quantities of somatic variants identified, the functional impact of many somatic variants, in particular the missense variants, remains unclear. Lack of the functional information prevents the translation of rich variation data into clinical applications. We previously developed a method named Ramachandran Plot-Molecular Dynamics Simulations (RP-MDS), aiming to predict the function of germline missense variants based on their effects on protein structure stability, and successfully applied to predict the deleteriousness of unclassified germline missense variants in multiple cancer genes. We hypothesized that regardless of their different genetic origins, somatic missense variants and germline missense variants could have similar effects on the stability of their affected protein structure. As such, the RP-MDS method designed for germline missense variants should also be applicable to predict the function of somatic missense variants. In the current study, we tested our hypothesis by using the somatic missense variants in TP53 as a model. Of the 397 somatic missense variants analyzed, RP-MDS predicted that 195 (49.1%) variants were deleterious as they significantly disturbed p53 structure. The results were largely validated by using a p53-p21 promoter-green fluorescent protein (GFP) reporter gene assay. Our study demonstrated that deleterious somatic missense variants can be identified by referring to their effects on protein structural stability.

Chronic Lymphocytic Leukemia: Prognostic Factors in the Era of Novel Drugs.

Novel drugs have profoundly changed the outcomes in chronic lymphocytic leukemia (CLL) patients, and the traditional prognostic factors that were identified in the era of chemoimmunotherapy need to be validated in the context of these new targeted therapies. Currently, the most important prognostic genetic biomarkers are the immunoglobulin heavy chain variable (IGHV) mutational status, genetic aberrations including del(17p)/TP53 abnormalities, and the complex karyotype. In this review, we discuss the prognostic role of these genomic markers in relation to novel treatments. Moreover, we present and discuss new scoring systems that were elaborated and validated in the era of new drugs. In routine clinical practice, the application of an extensive genomic work-up with validated prognostic markers could improve the identification of "very high-risk" CLL patients who could benefit from novel, more effective targeted treatments.

Assessment of cytotoxic and genotoxic effects of glyphosate-based herbicide on glioblastoma cell lines: Role of p53 in cellular response and network analysis.

Glyphosate, the world's most widely used herbicide, has a low toxicity rating despite substantial evidence of adverse health effects. Furthermore, glyphosate-based formulations (GBFs) contain several other chemicals, some of which are known to be harmful. Additionally, chronic, and acute exposure to GBFs among rural workers may lead to health impairments, such as neurodegenerative diseases and cancer. P53 is known as a tumor suppressor protein, acting as a key regulator of the cellular response to stress and DNA damage. Therefore, mutations in the TP53 gene, which encodes p53, are common genetic alterations found in various types of cancer. Therefore, this study aimed to evaluate the cytotoxicity and genotoxicity of GBF in two glioblastoma cell lines: U87MG (TP53-proficient) and U251MG (TP53-mutant). Additionally, the study aimed to identify the main proteins involved in the response to GBF exposure using Systems Biology in a network containing p53 and another network without p53. The MTT assay was used to study the toxicity of GBF in the cell lines, the clonogenic assay was used to investigate cell survival, and the Comet Assay was used for genotoxicity evaluation. For data analysis, bioinformatics tools such as String 12.0 and Stitch 5.0 were applied, serving as a basis for designing binary networks in the Cytoscape 3.10.1 program. From the in vitro test analyses, it was observed a decrease in cell viability at doses starting from 10 ppm. Comet Assay at concentrations of 10 ppm and 30 ppm for the U251MG and U87MG cell lines, respectively observed DNA damage. The network generated with systems biology showed that the presence of p53 is important for the regulation of biological processes involved in genetic stability and neurotoxicity, processes that did not appear in the TP53-mutant network.

Identify truly high-risk TP53-mutated diffuse large B cell lymphoma patients and explore the underlying biological mechanisms.

TP53 mutation (TP53-mut) correlates with inferior survival in many cancers, whereas its prognostic role in diffuse large B-cell lymphoma (DLBCL) is still in controversy. Therefore, more precise risk stratification needs to be further explored for TP53-mut DLBCL patients. A set of 2637 DLBCL cases from multiple cohorts, was enrolled in our analysis. Among the 2637 DLBCL patients, 14.0% patients (370/2637) had TP53-mut. Since missense mutations account for the vast majority of TP53-mut DLBCL patients, and most non-missense mutations affect the function of the P53 protein, leading to worse survival rates, we distinguished patients with missense mutations. A TP53 missense mutation risk model was constructed based on a 150-combination machine learning computational framework, demonstrating excellent performance in predicting prognosis. Further analysis revealed that patients with high-risk missense mutations are significantly associated with early progression and exhibit dysregulation of multiple immune and metabolic pathways at the transcriptional level. Additionally, the high-risk group showed an absolutely suppressed immune microenvironment. To stratify the entire cohort of TP53-mut DLBCL, we combined clinical characteristics and ultimately constructed the TP53 Prognostic Index (TP53PI) model. In summary, we identified the truly high-risk TP53-mut DLBCL patients and explained this difference at the mutation and transcriptional levels.

Generation of two induced pluripotent stem cell lines from patients with Li-Fraumeni Syndrome carrying TP53 mutation.

Li-Fraumeni syndrome (LFS) is a rare autosomal dominant inherited genetic disorder that greatly increases the risk of developing several types of cancer, including young children and young adults. LFS is primarily caused by specific mutations in the tumor suppressor gene TP53. In this study, we successfully generated two human induced pluripotent stem cell (iPSC) lines derived from patients diagnosed with LFS, each carrying a distinct heterozygous mutation in the TP53 gene. These LFS patient-derived iPSC lines exhibited robust expression of key pluripotency markers, demonstrated the capacity to differentiate into all three germ layers (endoderm, mesoderm, and ectoderm), and maintained a normal karyotype. The establishment of these iPSC lines provides a valuable tool for modeling LFS in vitro, enabling researchers to investigate the underlying pathological mechanisms associated with the disease across various cell types and tissues.

Mutant TP53 switches therapeutic vulnerability during gastric cancer progression within interleukin-6 family cytokines.

Although aberrant activation of the KRAS and PI3K pathway alongside TP53 mutations account for frequent aberrations in human gastric cancers, neither the sequence nor the individual contributions of these mutations have been clarified. Here, we establish an allelic series of mice to afford conditional expression in the glandular epithelium of KrasG12D;Pik3caH1047R or Trp53R172H and/or ablation of Pten or Trp53. We find that KrasG12D;Pik3caH1047R is sufficient to induce adenomas and that lesions progress to carcinoma when also harboring Pten deletions. An additional challenge with either Trp53 loss- or gain-of-function alleles further accelerated tumor progression and triggered metastatic disease. While tumor-intrinsic STAT3 signaling in response to gp130 family cytokines remained as a gatekeeper for all stages of tumor development, metastatic progression required a mutant Trp53-induced interleukin (IL)-11 to IL-6 dependency switch. Consistent with the poorer survival of patients with high IL-6 expression, we identify IL-6/STAT3 signaling as a therapeutic vulnerability for TP53-mutant gastric cancer.

Increased TP53 somatic evolution in peritoneal washes of individuals with BRCA1 germline mutations.

BACKGROUND: Individuals with germline BRCA1 and BRCA2 pathogenic variants (BRCA carriers) are at high risk of developing high grade serous ovarian carcinoma (HGSC). HGSC is predominantly driven by TP53 mutations, but mutations in this gene are also commonly found in non-cancerous tissue as a feature of normal human aging. We hypothesized that HGSC predisposition in BRCA carriers may be related to increased TP53 somatic evolution, which could be detectable by ultra-deep sequencing of TP53 mutations in gynecological liquid biopsies. METHODS: Duplex sequencing was used to identify TP53 mutations with high sensitivity in peritoneal washes and cervical liquid-based cytology (LBC) collected at surgery from 60 individuals including BRCA1 and BRCA2 carriers, and non-carriers. TP53 mutation pathogenicity was compared across groups and with TP53 cancer mutations. RESULTS: TP53 mutations were more abundant in cervical LBC than in peritoneal washes but increased with age in both sample types. In peritoneal washes, but not in cervical LBC, pathogenic TP53 mutation burden was increased in BRCA1 carriers compared to non-carriers, independently of age. Five individuals shared identical pathogenic TP53 mutations in peritoneal washes and cervical LBC, but not in blood. CONCLUSIONS: Ultra-deep sequencing of TP53 mutations in peritoneal washes collected at surgery reveals increased burden of pathogenic TP53 mutations in BRCA1 carriers. This excess of pathogenic TP53 mutations might be linked to the elevated risk of HGSC in these individuals. In some patients, concordant TP53 mutations were found in peritoneal washes and cervical LBCs, but the cell of origin remains unknown and deserves further investigation.

Venetoclax-based non-intensive induction followed by allogenic stem-cell transplantation in elderly acute myeloid leukemia patients with adverse cytogenetics.

INTRODUCTION: Elderly acute myeloid leukemia (AML) patients with poor-risk cytogenetics have a poor outcome with intensive chemotherapy (IC). While Venetoclax (VEN) has changed the outcomes of elderly unfit patients treatment, it is unknown whether it could be effective in poor-risk cytogenetics 60-75 years old patients. MATERIALS AND METHODS: We included 60-75-year-old AML patients eligible to allogenic stem cell transplantation (allo-SCT) treated with VEN (combined with azacitidine or with Cladribin and Aracytine) at Institut Paoli Calmettes, between 2020 and 2023 and compared this cohort with patients treated by IC between 2010 and 2019. RESULTS: Twenty six patients were treated with VEN (17 in combination with azacitidine and 9 with Cladribin and Aracytine) and 90 were treated with IC. Thirteen patients (50%) had a TP53 mutation. The median time for leucocyte and platelet counts recovery was 26 days (range 0-103) and 26 days (range, 0-63). The median duration of the first hospitalization was 32 days (ranges, 7-79). The composite response rate was 69% (CR = 50%, CRi = 4%, MLFS = 15%). Allo-SCT could be performed in 42% of cases. Median overall survival (OS) was 7.9 months (20.9 months in the group of patients who transitioned to allo-SCT). We found no difference with the historical cohort of patients treated with IC except a trend toward less lower and upper tract gastro-intestinal (GI) tract infections in the VEN group (respectively 8% vs 26%, p = .06; and 0% vs. 13% p = .06). CONCLUSION: VEN-based treatment was found to be effective in high risk AML can be considered as an alternative to IC in patients aged 60-75 with adverse cytogenetics.