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Phase 1 trial and biomarker analysis of Buparlisib with weekly Cisplatin and Radiotherapy in high risk locally advanced squamous cell cancer of the Head and Neck.

PURPOSE: We evaluated the pan-PI3K inhibitor buparlisib with weekly cisplatin and radiotherapy among patients with locally advanced (LA) squamous cell cancer of the head and neck (SCCHN) and tobacco history. PATIENTS AND METHODS: Patients with stage III/IV LA-SCCHN (AJCC7), ≥10 pack-year tobacco use treated with curative intent were enrolled. Patients received buparlisib during a 2-week run-in phase and during standard 70Gy of radiotherapy plus weekly cisplatin. An exploratory analysis of genomic sequencing was performed on biopsy specimens Results: Twenty-three patients were enrolled (n=17 at the MTD (buparlisib 40 mg daily, CDDP 30mg/m2/week)). Ninety-one percent (21/23) had stage IV disease. HPV was detected in 15 of 18 cases with oral/oropharyngeal disease. 5 patients suffered recurrences of whom 3 had activating mutations along the PI3K pathway. In 5 patients whose disease responded during the 2 week run-in phase with buparlisib alone, 3 of 4 with sequencing data showed loss-of-function mutations in either Tumor Necrosis Factor Receptor Associated Factor 3 (TRAF3), and/or Cylindromatosis Lysine Deubiquinatinase (CYLD). Preclinical studies with mutations in TRAF3 or CYLD via CRISPR/Cas9 knockout in HPV+SCCHN cells demonstrate that loss of TRAF3 or CYLD may sensitize SCCHN cell lines to PI3K through mechanisms other than blocking NFκb pathway. CONCLUSIONS: Buparlisib with CRT was feasible and active, though escalation to the standard weekly cisplatin dose of 40 mg/m2 was not possible. Our data suggests that TRAF3/CYLD mutant SCCHN may be susceptible to PI3K inhibition whereas PI3K pathway activation appeared to be associated with poor outcomes in this limited dataset.

Journal Article

Origin heterogeneity of Hb Lepore-Boston gene in Italy.

Forty-three hybrid delta-beta-globin genes were characterized by DNA sequence analysis and associated RFLP haplotypes in 40 families from Abruzzo and Campania, which are on the east and west coast of Italy, respectively. All the genes had the delta-globin sequence up to the exon 2 codon 87 and had the beta-globin sequence from IVS-2-8; between these two ends, they had 58 bp in common with the delta- and beta-globin genes. Thus, they were all of the Lepore-Boston type. A chromosomal background heterogeneity was present among the mutant genes. In fact, they were all associated with (+ - - - -) 5' subhaplotype, but 23/31 from Campania were associated with (+ +) 3' subhaplotype, whereas 12/12 genes from Abruzzo and 8/31 from Campania were associated with (+ -). DNA sequencing of homozygous subjects showed that (+ +) 3' subhaplotype was associated, at IVS-2-74, with G, while (+ -) was associated with T; that is they were associated with the beta-globin gene sequence of frameworks 1 and 2, respectively. The molecular characteristics of this heterogeneity, as well as its geographical patterns in the eastern and western regions of Italy, represent strong evidence for the recurrent and multicentric origins of the mutation.

Base Sequence

Comprehensive analysis of a novel LYST mutation in a Tunisian patient with Chediak-Higashi syndrome.

BACKGROUND: Chediak-Higashi Syndrome (CHS) is a rare autosomal recessive disorder characterized by oculocutaneous albinism, recurrent infections, bleeding tendencies, and progressive neurological impairment. The syndrome is caused by mutations in the LYST gene, which plays a crucial role in lysosomal trafficking. OBJECTIVE: This study aims to characterize the molecular basis of CHS in a Tunisian patient by identifying mutations in the LYST gene and analyzing their impact on the protein function, correlating these findings with the patient's clinical presentation. METHODS: A comprehensive clinical assessment was conducted on the patient, followed by biochemical, hematological, and microbiological analyses. Additionally, LYST protein levels were quantified in the patient and their parents using an ELISA assay. Genomic DNA was extracted from the patient's blood, and Whole Exome Sequencing (WES) was performed to identify mutations in the LYST gene. The findings were confirmed through Sanger sequencing, and bioinformatic tools were employed to predict the functional consequences of the detected mutations. RESULTS: The patient presented with classical symptoms of CHS, including silver hair, hypopigmented skin, recurrent infections, and neurological decline, with an unusually late onset at 18 years. ELISA results demonstrated significantly reduced LYST levels in the patient (1.8 ng/ml) compared to heterozygous parents (7.8 ng/ml and 8.1 ng/ml) and controls (9.2 ng/ml). Genetic analysis revealed a novel homozygous deletion, c.10269_10275del (p.Gly3424SerfsTer15), in the LYST gene, leading to a frameshift mutation and premature termination of the protein. Bioinformatic analysis demonstrated that this mutation leads to the deletion of five out of sven WD40 repeats in the protein's C-terminal region, which are critical for protein-protein interactions and lysosomal trafficking. CONCLUSION: The study identifies a novel LYST mutation in a Tunisian patient with CHS, expanding the spectrum of known genetic variants associated with the disease. The findings highlight the importance of genetic screening in populations with high consanguinity and underscore the need for targeted therapies to address the molecular defects in CHS.

Adolescent

Occurrence of p53 gene deletions and human papilloma virus infection in human head and neck cancer.

Little is known regarding the molecular genetic events in head and neck carcinoma. Epidemiological evidence suggests that both alcohol and tobacco use are related to the development of these neoplasms, and viral infections have also been postulated to play a role in some tumors. Loss of p53 tumor suppressor gene function has been found in many malignancies and can occur through either gene mutation or by interaction with the E6 protein of oncogenic human papilloma viruses (HPV). Because the mucosal surfaces of the head and neck are exposed to mutagens and HPVs, we studied DNA derived from 30 stage I-IV squamous cell carcinomas of the head and neck (9 primary tumors and 21 early passage cell lines) for p53 gene mutations as well as for the presence of oncogenic HPV DNA. Exons 2 through 11 of the p53 gene were examined using single strand conformation polymorphism analysis followed by direct genomic sequencing of all variants. HPV detection was done using polymerase chain reaction amplification with HPV E6 region type specific primers as well as L1 region degenerate ("consensus") primers; HPV type was determined by restriction fragment length polymorphism analysis of the amplified fragment as well as by Southern blotting of genomic DNA. Sixteen of 30 tumors (53%) had p53 mutations and oncogenic HPV DNA was detected in 3 of 30 (10%) tumors, none of which had p53 mutations. The p53 mutational spectrum observed was characterized by equal frequencies of transversions (6 of 16), transitions (5 of 16), and deletions (5 of 16). This distribution of mutations differs from the spectrum of p53 mutation reported in esophageal (P = 0.05) and lung (P = 0.02) cancers, two other tobacco associated neoplasms. A previously undescribed clustering of 3 mutations at codon 205 was also observed. A trend toward a shorter time to tumor recurrence after treatment was noted for those patients with tumors exhibiting p53 gene mutations, and no relationship between p53 mutations and tumor stage or node status was noted. Alteration in p53 gene function appears common in head and neck cancer, and the mutational spectrum observed may reflect the role of different mutagens or mutagenic processes than those responsible for the p53 mutations in lung and esophageal neoplasms.

Alcohol Drinking

RNF43 Mutations Are Associated With the Classical Molecular Subtype, Vigorous Antitumor Immune Responses, and Prolonged Survival in Pancreatic Adenocarcinoma.

RNF43 mutations were correlated with microsatellite status in colorectal cancer and with fewer and later recurrences in pancreatic ductal adenocarcinoma (PDAC). Here, we undertake a detailed assessment of RNF43 mutations in PDAC. A total of 313 PDACs (308 microsatellite stable [MSS] and 5 microsatellite-instable [MSI] cases) underwent next-generation sequencing (Oncomine Tumor Mutation Load assay; Thermo Fisher). Spatial analyses (NanoString) classified PDACs according to their transcriptomic and proteomic immune signaling. Fluorescent imaging was used to define spatial compartments (tumor: pancytokeratin+/CD45- and leukocytes: pancytokeratin-/CD45+). Each of 20 PDACs with RNF43 mutations (RNF43mut) and without RNF43 mutations (RNF43wt) underwent multiplex immunofluorescence analysis to determine immune status. A total of 153 PDACs (22 RNF43mut and 131 RNF43wt cases) underwent bulk RNA sequencing to assign into molecular subtypes. Overall, 24 RNF43 mutations were identified (22 MSS PDACs and 2 MSI PDACs). The incidence of RNF43 mutations in MSS PDACs (7.1%) was consistent with The Cancer Genome Atlas (6.7%). However, RNF43 mutations were more frequent among MSI PDACs (40%). Additionally, RNF43mut had differential frequencies of other mutations (including Wnt pathway genes), higher tumor mutational burden values (5.5 mut/mb vs 1.67 mut/mb; P < .01), and significantly longer overall survival (47 vs 18 months; P < .0001) than RNF43wt. Moreover, RNF43mut exhibited significantly higher densities of CD8+ T lymphocytes, dendritic cells, and B lymphocytes (P < .001) and an upregulation of ITGAX, CD11c, CD8, and HLA-DR compared with RNF43wt. Patients with RNF43mut PDACs were more often of the classical molecular subtype (20/22, 90.9%). RNF43mut PDACs showed high tumor mutational burden values, suggesting increased neoantigen load coupled with an abundance of antigen-presenting immune cells and an upregulation of immune determinants promoting antigen presentation. All this contributes to stronger antitumor immune responses and improved clinical outcomes.

Humans

Ovarian Carcinoma Presenting Mucoepidermoid Carcinoma-Like Features in Association With Seromucinous Borderline Tumor: A Real Seromucinous Carcinoma?

Ovarian seromucinous carcinoma is generally classified within the spectrum of endometrioid carcinoma. We report a rare ovarian carcinoma with mucoepidermoid carcinoma-like features arising in direct association with a seromucinous borderline tumor. A 56-year-old postmenopausal female presented with a 10-cm pelvic multilocular cystic tumor and markedly elevated carbohydrate antigen 19-9. Histopathological examination showed a seromucinous borderline tumor with transition to invasive carcinoma composed of mucinous epithelial cells and p40-positive intermediate-like cells. The tumor was diffusely positive for PAX8 and negative for cytokeratin 20, supporting Mullerian differentiation. The p40-positive cell population persisted in the borderline, invasive, and para-aortic lymph node metastatic components. Comprehensive genomic profiling identified KRAS p.G12D without CTNNB1, PTEN, or ARID1A mutations. The patient developed platinum-resistant recurrence and died 11 months after diagnosis. This case is compatible with a potential endometriosis-independent pathway from seromucinous borderline tumor to an aggressive mucoepidermoid-like carcinoma.

mucoepidermoid carcinoma

Apert syndrome with partial preaxial polydactyly.

Acrocephalosyndactyly type I or Apert syndrome is characterized by craniosynostosis, particular dysmorphic features and abnormalities of the hands and feet. Rarely, polydactyly of the toes has been reported, and in this event the diagnosis of Carpenter syndrome must be discussed. A case of atypical Acrocephalosyndactyly type I syndrome with partial preaxial polydactyly is reported. Despite this preaxial polydactyly a diagnosis of Apert syndrome consecutive to a new mutation was made, and the possibility of recurrence considered to be highly improbable.

Acrocephalosyndactylia

Detection of H-ras gene point mutations in transitional cell carcinoma of human urinary bladder using polymerase chain reaction.

It has been reported that the H-ras gene is activated as oncogene in human bladder cancer cases, and that codon 12 and codon 61 are the major "hot spots" of its activation. A simple method to detect point mutations in these codons of H-ras gene was established for the use of clinical diagnosis. In this method, the DNA segments including codon 12 or codon 61 were amplified by polymerase chain reaction (PCR), and the reaction products were examined for their susceptibility to the restriction enzyme NaeI or BstNI, and by dot blot hybridization assay with oligonucleotide probes. Point mutations were detectable in small amounts of DNAs isolated from fresh or frozen tumor tissues, urine cells and paraffin sections. The method was applied for a clinical sample and a case that had a point mutation at codon 12 of H-ras gene was detected. The point mutation was existed in DNAs of primary tumor tissue, all recurrent tumor tissues and cells isolated from urine of this case.

Base Sequence

Identification of a novel heterozygous GPD1 missense variant in a Chinese adult patient with recurrent HTG-AP consuming a high-fat diet and heavy smoking.

BACKGROUND: Glycerol-3-phosphate dehydrogenase 1 (GPD1) gene defect can cause hypertriglyceridemia (HTG), which usually occurs in infants. The gene defect has rarely been reported in adult HTG patients. In the present study, we described the clinical and functional analyses of a novel GPD1 missense variant in a Chinese adult patient with recurrent hypertriglyceridemia&#x2011;related acute pancreatitis (HTG-AP), consuming a high-fat diet and smoking heavily. METHODS: Exome sequencing was used to analyze the DNA of the adult patient's blood sample. It was found that there was a new variant of GPD1 gene-p.K327N, which was verified by gold standard-sanger sequencing method. In vitro, the corresponding plasmid was constructed and transfected into human renal HEK-293T cells, and GPD1 protein levels were detected. A biogenic analysis was performed to study the population frequency, conservation, and electric potential diagram of the new variant p.K327N. Finally, the previously reported GPD1 variants were sorted and their phenotypic relationships were compared. RESULTS: A novel heterozygous variant of GPD1, p.K327N (c.981G&#x2009;>&#x2009;C), was found in the proband. Furthermore, the patient's daughter carried this variant, whereas his wife did not carry the variant. The proband with obesity suffered eight episodes of HTG-AP from the age of 36 years, and each onset of AP was correlated to high-fat diet consumption and heavy smoking. In vitro, this variant exerted a relatively mild effect on GPD1 functions, which were associated with its effect upon secretion (~&#x2009;25% of secretion decreased compared with that of the wild-type); thus, eventually impairing protein synthesis. Additionally, 36 patients with GPD1 variants found in previous studies showed significant transient HTG in infancy. The proband carrying the GDP1 variant was the first reported adult with recurrent HTG-AP. CONCLUSION: We identified a novel GPD1 variant, p.K327N, in a Chinese adult male patient with recurrent HTG-AP. The variant probably exerted a mild effect on GPD1 functions. The heterozygosity of this GPD1 variant, in addition to high-fat diet consumption and heavy smoking, probably triggered HTG-AP in the patient.

Adult

Oncogenic PIK3CA reprograms glutamine metabolism to drive bladder cancer progression.

BACKGROUND: Genomic analysis has revealed that approximately 40% of bladder cancer (BLCA) tumors harbor alterations in the PI3K/AKT pathway, with PIK3CA mutations occurring in 15-25% of cases. PIK3CA, which encodes the catalytic p110&#x3b1; subunit of PI3K, plays a critical role in regulating cell survival, proliferation, and metabolism. However, the metabolic and functional consequences of PIK3CA mutations in BLCA remain poorly defined. METHODS: To investigate the role of PIK3CA mutations in BLCA, we performed targeted sequencing on tumors from patients, identifying recurrent alterations. Using CRISPR/Cas9 knock-in models in SCaBER and UM-UC-3 cell lines, we introduced the PIK3CA E545K mutation to study its effects. We conducted transcriptomic profiling, targeted metabolomics, and stable isotope tracing to assess metabolic reprogramming. Functional assays measured proliferation, mitochondrial complex I activity, and glutaminolysis. Orthotopic xenografts in mice were used to evaluate in vivo tumor growth and metabolism. RESULTS: PIK3CA mutations were present in 20% of cases, consistent with TCGA data. The E545K and E545Q hotspots accounted for 70% of these mutations. PIK3CA E545K strongly activated PI3K/AKT signaling. Transcriptomic analysis revealed enrichment of OXPHOS, fatty acid metabolism, and mTORC1 signaling. Metabolomics indicated changes in TCA cycle metabolites and enhanced reductive carboxylation of glutamine to citrate, driving fatty acid synthesis. Mutant cells showed increased expression of GLS1 and FASN, higher proliferation rates, and elevated mitochondrial complex I activity. In vivo, PIK3CA-mutant xenografts displayed significantly increased tumor growth. CONCLUSION: PIK3CA mutations are frequent drivers of metabolic reprogramming in BLCA, leading to increased glutamine flux, elevated OXPHOS activity, and enhanced fatty acid synthesis, all of which contribute to tumor progression. These findings provide the first comprehensive evidence that PIK3CA-driven metabolic alterations are both biomarkers of aggressive disease and actionable therapeutic targets. The efficacy of PI3K&#x3b1; inhibition in combination with metabolic targets may support its potential in precision medicine for PIK3CA-mutant BLCA and highlights the value of integrating metabolic biomarkers into treatment strategies for advanced BLCA.

Journal Article

Serial CSF CA19-9 monitoring and CSF genomic profiling in ERBB2-mutant lung adenocarcinoma with leptomeningeal metastasis: a case report.

Leptomeningeal metastasis (LM) from ERBB2-mutant lung adenocarcinoma is difficult to treat and monitor because systemic disease and leptomeningeal disease may evolve discordantly. Evidence regarding cerebrospinal fluid (CSF) genomic profiling and serial CSF tumor marker monitoring in ERBB2-mutant non-small cell lung cancer with LM remains limited. We report a 48-year-old woman initially diagnosed with stage IB mucinous lung adenocarcinoma harboring an ERBB2 exon 20 p.G776delinsVC mutation. After surgery and adjuvant chemotherapy, she developed nodal recurrence and later presented with lower back pain and lower-limb numbness. LM was clinically diagnosed based on neurological symptoms, magnetic resonance imaging and CSF cytopathology. She received craniospinal irradiation, systemic therapy and subsequent intrathecal treatment. At month 33, CSF CA19-9 was markedly elevated despite no clear radiographic systemic progression. CSF&#xa0;next-generation sequencing(NGS) detected the same ERBB2 exon 20&#xa0;p.G776delinsVC mutation as the primary lung tumor, with a higher variant allele&#xa0;fraction in CSF than in lung tissue.The patient subsequently received trastuzumab&#xa0;deruxtecan and sequential intrathecal therapy with pemetrexed, etoposide,&#xa0;cytarabine and pemetrexed rechallenge. Intrathecal treatment was adjusted according to serial CSF CA19-9 levels, neurological status, imaging findings, systemic disease activity and treatment-related toxicities. CSF CA19-9 was not used as a stand-alone criterion for progression or treatment modification.At the latest follow-up, she remained alive more than 36 months after the clinical diagnosis of LM. This case suggests that CSF NGS and serial CSF CA19-9 may provide further insights into disease activity within the integrated assessment of systemic and leptomeningeal disease. Their clinical applicability is still under investigation and necessitates future validation.

CA19-9

AUTS2-related syndrome: Insights from a large European cohort.

PURPOSE: AUTS2-related syndrome is characterized by developmental delay, autism spectrum disorder, and intellectual disability. From alternative promoters, AUTS2 encodes 2 distinct long and short isoforms encoding a putative transcriptional activator. METHODS: Through a European collaborative study, we collected clinical and genotype data on the largest AUTS2-related syndrome cohort of 58 patients harboring genomic rearrangements or single-nucleotide variants (SNVs). RESULTS: Pathogenic SNVs were recurrently found in individuals from different countries, suggesting mutational hotspots. Independent of the underlying defect at the AUTS2 locus, we observed that autistic behavior, hyperactivity, learning difficulties, and speech delay are common features of AUTS2-related syndrome. Among patients with SNVs, individuals carrying pathogenic variants affecting both longer and shorter AUTS2 transcripts showed a recognizable phenotype with microcephaly, brachycephaly, microretrognathia, broad nasal base, and anteverted nares. Behavioral disorders were more common in patients with variants affecting only the longer isoform. Arthrogryposis and stiff movements were only observed in patients with SNVs. CONCLUSION: This study provides a comprehensive clinical characterization of AUTS2-related syndrome, reveals few genotype-phenotype correlations, and suggests that the disruption of the 2 distinct AUTS2 transcripts has a different impact on the clinical phenotype.

Humans

On the variable expression of the Brachmann-de Lange syndrome.

A mother of normal intelligence and her moderately mentally retarded son, both with the typical facial features of the Brachmann-de Lange syndrome, are reported. We discuss the variable expression of the Brachmann-de Lange syndrome by comparing the autosomal dominant cases with the sporadic or presumed autosomal recessive cases. The autosomal dominant cases show milder symptoms in general. In our opinion, a de novo autosomal dominant mutation causes the severe form of the syndrome, recurrence within sibships being explained by germline mosaicism. In all convincingly autosomal dominant cases we found that the mother is the transmitting parent, suggesting genomic imprinting.

Adult

Tracking Nongenetic Evolution from Primary to Metastatic ccRCC: TRACERx Renal.

While the key aspects of genetic evolution and their clinical implications in clear cell renal-cell carcinoma (ccRCC) are well-documented, how genetic features co-evolve with the phenotype and tumor microenvironment (TME) remains elusive. Here, through joint genomic-transcriptomic analysis of 243 samples from 79 patients recruited to the TRACERx Renal study, we identify pervasive non-genetic intratumor heterogeneity, with over 40% not attributable to genetic alterations. By integrating tumor transcriptomes and phylogenetic structures, we observe convergent evolution to specific phenotypic traits, including cell proliferation, metabolic reprogramming and overexpression of putative cGAS-STING repressors amid high aneuploidy. We also uncover a co-evolution between the tumor and the T cell repertoire, as well as a longitudinal shift in the TME from an anti-tumor to an immunosuppressive state, linked to the acquisition of recurrently late ccRCC drivers 9p loss and SETD2 mutations. Our study reveals clinically-relevant and hitherto underappreciated non-genetic evolution patterns in ccRCC.

Journal Article

Osimertinib With or Without Chemotherapy in Advanced Non-Small Cell Lung Cancer With EGFR and Concurrent TP53 Mutations: A Randomized Clinical Trial.

IMPORTANCE: Combination therapy has emerged as a promising therapeutic approach for patients with epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC). However, its clinical benefit-risk profile remains a focus of ongoing debate. Identifying patients most likely to derive benefit from such regimens remains an unmet clinical need. OBJECTIVE: To prospectively compare the efficacy and safety of first-line osimertinib plus chemotherapy with osimertinib monotherapy for patients with EGFR-mutated advanced NSCLC harboring concurrent TP53 mutations. DESIGN, SETTING, AND PARTICIPANTS: A multicenter, randomized, open-label, phase 3 study conducted at 17 sites in China. Between March 25, 2021, and July 11, 2024, a total of 294 eligible patients with treatment-naive, stage IV or recurrent nonsquamous NSCLC harboring concurrent TP53 and EGFR-sensitizing mutations were enrolled. INTERVENTIONS: Patients were randomized (1:1) to receive osimertinib plus chemotherapy (pemetrexed and carboplatin every 3 weeks for 4 cycles, followed by maintenance therapy of osimertinib plus pemetrexed; n&#x2009;=&#x2009;146) or osimertinib monotherapy (n&#x2009;=&#x2009;148). MAIN OUTCOMES AND MEASURES: The primary end point was investigator-assessed progression-free survival. Secondary end points included overall survival, response, safety, and quality of life. RESULTS: Among 294 enrolled patients, the median age was 57 years (range, 26-79 years), and 159 (54.1%) were female. The data cutoff date was November 11, 2025. At a median follow-up of 25.1 months for the osimertinib-chemotherapy group and 26.1 months for the osimertinib monotherapy group, median progression-free survival was significantly longer with osimertinib plus chemotherapy than with osimertinib monotherapy (34.0 vs 15.6 months; difference, 18.4 months [95% CI, 9.9-22.3]; hazard ratio, 0.44 [95% CI, 0.32-0.60]; P&#x2009;<&#x2009;.001). This benefit was consistent across prespecified subgroups, including those with brain metastases and L858R mutations. The overall survival data remained immature (30.6% maturity); however, a trend toward overall survival benefit with combination therapy was observed. The incidence of grade 3 or higher treatment-related adverse events was higher in the combination group, with no new safety signal identified. CONCLUSIONS AND RELEVANCE: In this randomized clinical trial, osimertinib plus chemotherapy significantly increased progression-free survival among patients with EGFR-mutated advanced NSCLC harboring concurrent TP53 mutations. These findings provided a clinical rationale for individualized combination strategies in the management of patients with EGFR-mutated NSCLC. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04695925.

Adult

Molecular Analysis of Persistent and Recurrent Barrett's Esophagus in the Setting of Endoscopic Therapy.

INTRODUCTION: Early neoplastic progression of Barrett's esophagus (BE) is often treated with endoscopic therapy. Although effective, some patients are refractory to therapy or recur after apparent eradication of the BE. The goal of this study was to determine whether genomic alterations within the treated BE may be associated with persistent or recurrent disease. METHODS: We performed DNA sequencing on pre-treatment esophageal samples from 45 patients who were successfully treated by endoscopic therapy and did not recur as well as pre-treatment and post-treatment samples from 40 patients who had persistent neoplasia and 21 patients who had recurrent neoplasia. The genomic alterations were compared between groups. RESULTS: The genomic landscape was similar between all groups. Patients with persistent disease were more likely to have pre-treatment alterations involving the receptor tyrosine kinase pathway ( P = 0.01), amplifications of oncogenes ( P = 0.01), and deletions of tumor suppressor genes ( P = 0.02). These associations were no longer significant after adjusting for patient age and BE length. More than half of patients with persistent (52.5%) or recurrent (57.2%) disease showed pre-treatment and post-treatment samples that shared at least 50% of their driver mutations. DISCUSSION: Pre-treatment samples were genomically similar between those who responded to endoscopic therapy and those who had persistent or recurrent disease, suggesting there is not a strong genomic component to treatment response. Although it was expected to find shared driver mutations in pre-treatment and post-treatment samples in patients with persistent disease, the finding that an equal number of patients with recurrent disease also showed this relation suggests that many recurrences represent undetected minimal residual disease.

Humans

The clinical landscape of POLE-mutant colorectal cancer: a retrospective analysis of real-world outcome.

BACKGROUND: Pathogenic mutations in the POLE gene disrupt its proofreading function during DNA replication, causing an accumulation of erroneous nucleotide incorporations. This defect leads to a significantly elevated tumor mutation burden (TMB) and increased generation of tumor neoantigens. These molecular characteristics suggest a potential association between POLE-mutant tumors and distinct prognostic outcomes in colorectal cancer (CRC); however, clinical evidence supporting this correlation remains limited. METHODS: We retrospectively collected a cohort of CRC patients harboring pathogenic POLE mutations. Comparative analyses were performed between POLE-mutant and POLE wild-type CRCs regarding their clinical characteristics, prognostic outcomes, and genomic profiles. Additionally, we evaluated the response to immunotherapy in metastatic POLE-mutant CRC cases. RESULTS: Among 35,108 CRC patients, pathogenic POLE mutations were identified in 261 individuals, accounting for 0.74% of the cohort. The median age at diagnosis for POLE-mutant patients was 48&#xa0;years, with a male predominance (74.4%) and a substantial proportion (50.4%) of tumors localized in the right-sided colon. All patients with pathogenic POLE mutations exhibited hypermutated phenotypes, characterized by a median TMB of 235.26 mutations per megabase (range: 71.20-719.00 mutations/Mb). In stage II CRC, POLE mutations were significantly associated with a reduced risk of recurrence (hazard ratio [HR] 0.344, 95% confidence interval [CI] 0.157-0.754, p&#x2009;=&#x2009;0.008) when compared to POLE wild-type, microsatellite stable CRC patients. However, this association was not evident in stage III patients (HR 1.004, 95% CI 0.490-2.057, p&#x2009;=&#x2009;0.992). Importantly, the incorporation of immune checkpoint inhibitors in first-line treatment regimens significantly improved progression-free survival (HR&#x2009;=&#x2009;0.247, 95% CI 0.117-0.552, p&#x2009;=&#x2009;0.0002) and overall survival (HR&#x2009;=&#x2009;0.317, 95% CI 0.103-1.143, p&#x2009;=&#x2009;0.0832) in metastatic CRC patients with pathogenic POLE mutations. CONCLUSIONS: Pathogenic POLE-mutant CRC constitutes a relatively rare, yet clinically important, subtype. These cancers exhibit distinct clinicopathological and genomic features. Our results indicate that mutations in the POLE gene may serve as a valuable prognostic marker and a potential indicator of benefit to immunotherapy in CRC, offering promising avenues for personalized treatment strategies.

Humans