PubMed HealthSearch

SEARCH · PubMed Health

Results for “PIK3CA”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources

Clinically actionable genomic alterations in breast cancer brain metastases.

BACKGROUND: Breast cancer brain metastases (BCBMs) represent a critical unmet clinical need in metastatic breast cancer (MBC) and the identification of novel therapeutic targets is urgently needed in this context. In this study, we describe clinically actionable targets in BCBMs using comprehensive genomic profiling. PATIENTS AND METHODS: Genomic DNA was extracted from formalin-fixed paraffin-embedded archival BCBM samples and analyzed using the commercially available Agilent SureSelect V6 whole exome sequencing (WES) kit and an Illumina NovaSeq 6000 platform. Pathogenic alterations were classified as actionable alterations (AAs) if they met the updated MBC or tumor-agnostic ESMO Scale for Clinical Actionability of Molecular Targets (ESCAT) I or II criteria of the ESCAT scale. RESULTS: WES data from 56 BCBM samples were available [33.9% hormone receptor (HR)-negative/human epidermal growth factor receptor (HER)2-negative; 25.0% HR-positive/HER2-negative; and 38% HER2-positive]. ESCAT I/II AAs were detected in 76.8% (n = 43) of all BCBMs and the most frequently detected AAs were in genes involved in the homologous recombination repair pathway (BRCA1/BRCA2/PALB2; 53.6% overall). Biallelic inactivation of BRCA1, BRCA2, or PALB2 was observed in 19.6% of samples, with higher rates in HER2-negative BCBMs (26% in HR-negative /HER2-negative and 21% in HR-positive/HER2-negative). ESCAT I/II PIK3CA/AKT1/PTEN pathway alterations were present in 48.2% of samples and, in particular, in 50% of HR-positive/HER2-negative BCBMs. No ESR1 mutation was detected in HR-positive/HER2-negative BCBMs. The prognostic impact of previously described AAs was evaluated overall and according to breast cancer subtype. Twenty-three BCBMs (41%) were classified as HER2-positive; among these, 3 (13%) presented a hotspot PIK3CA mutation and 7 (30%) presented a PTEN deletion. Among patients with HER2-positive BCBMs, the identification of a hotspot PIK3CA mutation was significantly associated with worse prognosis. CONCLUSIONS: ESCAT I/II actionable genomic alterations are frequent in BCBMs, highlighting the potential for genomically targeted treatments in this setting.

ESCAT

Genetic Analysis of Early Neoplasia in the Breast: Next-Generation Sequencing of Flat Epithelial Atypia and Associated Ductal and Lobular Lesions.

The molecular features of invasive breast cancers (IBC) have been well-characterized, but less is known about the earlier stages of neoplasia, including oncogenic drivers in early intraductal lesions. Flat epithelial atypia (FEA) is considered the earliest recognized precursor in the low-grade neoplasia pathway, but its mutational repertoire has not been studied, and drivers of the transition to morphologically more advanced lesions are unknown. Herein, we utilized next-generation sequencing to analyze 39 synchronous lesions from 13 patients, including FEA (n = 12) or predominantly FEA with early atypical ductal hyperplasia (FEA/early atypical ductal hyperplasia [ADH], n = 5) and associated ADH (n = 2), ductal carcinoma in situ (ductal carcinoma in situ [DCIS], n = 11), lobular carcinoma in situ (n = 3), and/or IBC with ductal and/or lobular differentiation (n = 6). Aside from 1 DCIS sample, all sequenced lesions in each patient were clonally related to one another. Recurrent alterations in FEA and FEA/early ADH included PIK3CA (69%), NCOR1 (31%), CBFB (31%), RUNX1 (15%), and GATA3 (23%). The mutational repertoire of FEA was similar to The Cancer Genome Atlas luminal IBC, except CBFB and NCOR1 mutations, which were more frequent in FEA and (along with PIK3CA, FOXA1, and CDKN1B) not always identified in paired morphologically advanced lesions. Compared with FEA, DCIS had more mutations and chromosomal copy number changes, including aberrations in PI-3 kinase pathway, transcription factors, chromatin remodeling genes, and TP53. CDH1 mutations identified in lobular carcinoma in situ were absent in paired FEA. Analysis of cases with ductal and lobular heterogeneity, including Rosen's triad, confirmed the shared clonality of the ductal and lobular components with features of genetic divergence. IBC of no special type were genetically similar to DCIS, and tubular carcinomas were similar to FEA. The results reveal the mutational repertoire of FEA and the genetics of early breast neoplasia, highlighting the clonal relationships of FEA to ductal and lobular carcinomas. Luminal breast cancer-associated genetic alterations are present at the earliest morphologically recognized stages of neoplasia.

Humans

Sanguinarine as a multi-target therapeutic candidate for laryngeal cancer: insights from network pharmacology, molecular dynamics and in vitro validation.

OBJECTIVE: To identify the core targets and elucidate the potential molecular mechanisms of sanguinarine (SA) against laryngeal squamous cell carcinoma (LSCC), and to validate its antitumor effects in vitro. METHODS: Potential targets of SA were predicted using SwissTargetPrediction, TargetNet, and SuperPred and intersected with LSCC-related targets obtained from the GeneCards, OMIM, and DISEASES databases. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were performed. A protein-protein interaction (PPI) network was constructed using the STRING database (combined score > 0.900), and topological parameters including degree centrality (DC), betweenness centrality (BC), closeness centrality (CC), eigenvector centrality (EC), and local average connectivity (LAC) were calculated in Cytoscape to identify core genes based on median thresholds. Molecular docking and 100-ns molecular dynamics (MD) simulations were conducted for epidermal growth factor receptor (EGFR), Phosphatidylinositide-3-kinase catalytic subunit alpha (PIK3CA), phosphatidylinositol-4,5-biphosphate 3-kinase catalytic subunit β (PIK3CB), phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit delta (PIK3CD), and Non-Receptor Tyrosine Kinase (SRC). The effects of SA on LSCC were evaluated using CCK-8, colony formation, Transwell migration, and wound-healing assays in TU177 cells and TU212. RESULTS: A total of 213 common targets were identified, which were significantly enriched in PI3K-Akt signaling, EGFR tyrosine kinase inhibitor resistance, and adhesion- and migration-related pathways. The PPI network comprised 259 nodes and 259 edges, from which five core genes-PIK3CA, PIK3CB, PIK3CD, EGFR, and SRC-were identified. Molecular docking revealed strong binding affinities between SA and the PI3K family proteins (- 9.79 to - 10.96 kcal/mol), as well as EGFR (- 8.58 kcal/mol) and SRC (- 6.77 kcal/mol). MD simulations indicated greater stability of SA complexes with EGFR and PI3K family members compared with SRC. In vitro assays demonstrated that SA significantly inhibited TU177 cell and TU212 cell proliferation, colony formation, and migration. CONCLUSION: SA may exert anti-laryngeal cancer effects through synergistic multi-target inhibition centered on the EGFR/SRC/PI3K signaling axis, highlighting its potential as a promising therapeutic candidate for LSCC.

Humans

Genomic landscape of hepatocellular carcinoma in Egyptian patients by whole exome sequencing.

BACKGROUND: Hepatocellular carcinoma (HCC) is the most common primary liver cancer. Chronic hepatitis and liver cirrhosis lead to accumulation of genetic alterations driving HCC pathogenesis. This study is designed to explore genomic landscape of HCC in Egyptian patients by whole exome sequencing. METHODS: Whole exome sequencing using Ion Torrent was done on 13 HCC patients, who underwent surgical intervention (7 patients underwent living donor liver transplantation (LDLT) and 6 patients had surgical resection}. RESULTS: Mutational signature was mostly S1, S5, S6, and S12 in HCC. Analysis of highly mutated genes in both HCC and Non-HCC revealed the presence of highly mutated genes in HCC (AHNAK2, MUC6, MUC16, TTN, ZNF17, FLG, MUC12, OBSCN, PDE4DIP, MUC5b, and HYDIN). Among the 26 significantly mutated HCC genes-identified across 10 genome sequencing studies-in addition to TCGA, APOB and RP1L1 showed the highest number of mutations in both HCC and Non-HCC tissues. Tier 1, Tier 2 variants in TCGA SMGs in HCC and Non-HCC (TP53, PIK3CA, CDKN2A, and BAP1). Cancer Genome Landscape analysis revealed Tier 1 and Tier 2 variants in HCC (MSH2) and in Non-HCC (KMT2D and ATM). For KEGG analysis, the significantly annotated clusters in HCC were Notch signaling, Wnt signaling, PI3K-AKT pathway, Hippo signaling, Apelin signaling, Hedgehog (Hh) signaling, and MAPK signaling, in addition to ECM-receptor interaction, focal adhesion, and calcium signaling. Tier 1 and Tier 2 variants KIT, KMT2D, NOTCH1, KMT2C, PIK3CA, KIT, SMARCA4, ATM, PTEN, MSH2, and PTCH1 were low frequency variants in both HCC and Non-HCC. CONCLUSION: Our results are in accordance with previous studies in HCC regarding highly mutated genes, TCGA and specifically enriched pathways in HCC. Analysis for clinical interpretation of variants revealed the presence of Tier 1 and Tier 2 variants that represent potential clinically actionable targets. The use of sequencing techniques to detect structural variants and novel techniques as single cell sequencing together with multiomics transcriptomics, metagenomics will integrate the molecular pathogenesis of HCC in Egyptian patients.

Humans

Genomic and epigenomic diversity of breast cancer across Western and MENA populations: implications for precision oncology.

Breast cancer is the most common malignancy in women worldwide and is increasingly recognized as a biologically diverse disease shaped by both molecular and ancestral context. Women from the Middle East and North Africa (MENA) populations, including Saudi Arabia, often present at a younger age and with more aggressive subtypes such as HER2-positive and triple-negative breast cancer (TNBC) compared with Western cohorts. These clinical patterns reflect a distinctive genomic background marked by high consanguinity, founder mutations in key susceptibility genes, and population-specific somatic alterations that are not fully captured in global reference datasets. This review brings together current evidence on somatic, germline, transcriptomic, and epigenomic diversity in breast cancer across Western and MENA populations, with a focus on Saudi cohorts. Drawing on a previously published systematic review of more than 2,500 MENA breast cancer cases, TP53 accounted for approximately 24% and PIK3CA for roughly 10% of curated somatic mutation records pooled across 44 studies (proportions of mutation calls, not per-patient prevalence); in a separate single-center Saudi cohort, only 3.7% of patients underwent BRCA testing, and 37.5% of this clinically selected, testing-referred subgroup carried a pathogenic variant, a figure that should not be read as general-population BRCA prevalence. Variants of uncertain significance exceeded 20% across several regional genomic studies. We summarize conserved driver events, such as recurrent TP53 and PIK3CA mutations, while highlighting regional features, including unique stop-gain and loss-of-function variants, a high copy-number burden, and early-onset disease linked to ancestral architecture. We also discuss emerging data on MENA-specific regulatory signatures, including immune-enriched and basal-myo transcriptomic clusters, CIMP-like methylation patterns, and non-coding RNA networks; these associations are numerically suggestive in available cohorts but have not reached statistical significance in existing studies and warrant validation in larger, dedicated MENA/Saudi cohorts before being considered established determinants of treatment response and resistance. Finally, we examine the clinical implications of this diversity for biomarker development, pharmacogenomics, and access to targeted therapies, and outline practical steps toward ancestry-aware precision oncology in the region.

BRCA

Propionyl-CoA carboxylase subunit B regulates anti-tumor T cells in a pancreatic cancer mouse model.

Most human pancreatic ductal adenocarcinoma (PDAC) are not infiltrated with cytotoxic T cells and are highly resistant to immunotherapy. Over 90% of PDAC have oncogenic KRAS mutations, and phosphoinositide 3-kinases (PI3Ks) are direct effectors of KRAS. Our previous study demonstrated that ablation of Pik3ca in KPC (KrasG12D; Trp53R172H; Pdx1-Cre) pancreatic cancer cells induced host T cells to infiltrate and completely eliminate the tumors in a syngeneic orthotopic implantation mouse model. Now, we show that implantation of Pik3ca-/- KPC (named αKO) cancer cells induces clonal enrichment of cytotoxic T cells infiltrating the pancreatic tumors. To identify potential molecules that can regulate the activity of these anti-tumor T cells, we conducted an in vivo genome-wide gene-deletion screen using αKO cells implanted in the mouse pancreas. The result shows that deletion of propionyl-CoA carboxylase subunit B gene (Pccb) in αKO cells (named p-αKO) leads to immune evasion, tumor progression, and death of host mice. Surprisingly, p-αKO tumors are still infiltrated with clonally enriched CD8+ T cells but they are inactive against tumor cells. However, blockade of PD-L1/PD1 interaction reactivated these clonally enriched T cells infiltrating p-αKO tumors, leading to slower tumor progression and improve survival of host mice. These results indicate that Pccb can modulate the activity of cytotoxic T cells infiltrating some pancreatic cancers and this understanding may lead to improvement in immunotherapy for this difficult-to-treat cancer.

Animals

Molecular and immune profiling of HER2-low, HER2 ultra-low, and HER2-null male breast cancer.

BACKGROUND: HER2 expression is described along a biological continuum from null to positive and serves as a critical biomarker for therapeutic guidance in breast cancer (BC). While HER2-low and ultra-low categories have emerged as actionable targets for antibody-drug conjugates (ADCs) in female BC, their molecular and immune characteristics remain largely unexplored in male breast cancer. METHODS: We profiled 214 male breast tumors using next-generation sequencing and whole-transcriptome sequencing to assess mutational, transcriptomic, and immune landscapes. Tumor mutational burden (TMB) was defined as high if > 10 mutations/Mb. Immune cell fractions were inferred using Quantiseq deconvolution. RESULTS: Among 214 samples, 66 (30.8%) were HER2-null, 53 (24.8%) HER2 ultra-low, 80 (37.4%) HER2-low, and 15 (7.0%) HER2-positive. HER2 ultra-low tumors exhibited a higher prevalence of PIK3CA mutations (39.2% vs 22.6%, p ≤ 0.05) compared to HER2-null. No significant differences were observed in TMB-high frequency or PD-L1 expression across subgroups. Immune composition differed primarily between HER2-null and HER2-expressing subgroups: HER2-ultra-low tumors showed higher B-cell infiltration, whereas HER2-null tumors were enriched in neutrophils. Transcriptomic analysis revealed upregulation of selected stemness-associated genes (NANOG, KLF4, POU5F1) and CEACAM1 in HER2-null tumors, while HER2-low and HER2-ultra-low tumors were largely similar across most molecular and immune readouts in this cohort. CONCLUSIONS: HER2-null male breast cancer appears to represent the most biologically divergent subgroup within the HER2-negative spectrum, whereas HER2-low and HER2-ultra-low tumors were largely similar in this cohort. These findings support further investigation of HER2-null disease as a distinct biological state and provide hypothesis-generating data for biomarker development in this rare population.

Male

Molecular characterization of salivary cancers: Patterns of genomic alterations and potential for impact on therapeutic choices.

BACKGROUND: Salivary cancers are rare malignancies with diverse histologies, molecular landscape, and limited effective systemic therapy options. Recent tumour genomics research has identified driver alterations in salivary gland cancers that have led to personalized therapy approaches. The primary objective was to perform molecular characterization using next generation sequencing (NGS) panel and evaluate the potential impact of results on clinical decision-making and treatment outcomes. METHODS: Patients with locally advanced or incurable metastatic salivary cancers suitable for systemic therapy underwent NGS tumour testing with an amplicon-based DNA/RNA NGS panel. Patient demographics, baseline characteristics, treatment and treatment outcomes were retrospectively collected. RESULTS: From 2021 to 2024, 58 advanced salivary cancer patients underwent molecular characterization of their tumour. Baseline characteristics at diagnosis: male 60%, median age 67, most common histologies; adenoid cystic 27%, salivary duct 19% and mucoepidermoid 12%. PIK3CA alterations were the most common molecular finding across all subtypes 22% (13/58) and were enriched in salivary duct carcinoma 73% (8/11). Other alterations identified were: ERBB2 (4), EGFR (2), HRAS (3), NTRK3 (2), BRAF p.V600E (1), and RET (1). Immunohistochemistry identified androgen receptor positivity across salivary cancer subtypes in 8/19 and HER2 positivity in 2/20 tested. Twenty-two patients received systemic therapy prior to NGS results for incurable/metastatic disease, first line treatments included 69% chemotherapy, 18% anti-androgen, 9% lenvatinib, 4% trial. CONCLUSION: Molecular characterization of salivary cancers identified targetable alterations in 37% of patients. The identification of potential therapeutic targets offers the opportunity for expanded treatment options to benefit salivary gland cancer patients.

Metastatic salivary gland cancer

Eribulin versus taxane as first-line chemotherapy combined with dual HER2 blockade in patients with HER2-positive locally advanced or metastatic breast cancer: final survival outcomes of the JBCRG-M06/EMERALD study.

BACKGROUND: The phase III JBCRG-M06/EMERALD study was the first to show noninferior progression-free survival (PFS) of eribulin to taxane, combined with dual human epidermal growth factor receptor 2 (HER2) blockade (trastuzumab plus pertuzumab), as a first-line treatment for HER2-positive locally advanced breast cancer or metastatic breast cancer (LABC/MBC). We report final survival outcomes and biomarker analyses of the EMERALD trial. PATIENTS AND METHODS: Patients with HER2-positive LABC/MBC were randomly assigned 1:1 to either eribulin or physician-choice taxane (docetaxel or paclitaxel), both combined with trastuzumab plus pertuzumab, as first-line chemotherapy. PFS and overall survival (OS) were assessed through 30 June 2023 for PFS and 31 December 2024 for OS. Survival outcomes were compared between the eribulin and taxane groups and according to circulating tumor DNA (ctDNA) detection of PIK3CA mutations (PIK3CAm+; E542K, E545K, H1047R, and N345K single nucleotide variants) or HER2 amplification (HER2 amp+; ERBB2 copy number >2.5). RESULTS: Median OS was 78.5 months [95% confidence interval (CI) 64.3-not reached (NR)] for eribulin and was NR for taxane, with a hazard ratio of 1.25 (95% CI 0.92-1.71, log-rank P = 0.19). The 60-month OS rates were 59.7% and 65.2% for eribulin and taxane, respectively. Median OS and 60-month OS rates were numerically lower in ctDNA PIK3CAm+ patients, and greater in ctDNA HER2 amp+ patients for all patients and with stratification by treatment group. There were no statistical interactions between treatment group with either ctDNA PIK3CAm or ctDNA HER2 amp status. Similar patterns were observed for PFS. CONCLUSION: Final survival analysis revealed that median OS exceeded 6 years with eribulin or physician-choice taxane, combined with trastuzumab plus pertuzumab, as first-line chemotherapy for HER2-positive LABC/MBC, with no significant differences between the two groups. ctDNA PIK3CAm+ status was a poor prognostic factor. ctDNA HER2 amp+ was associated with longer survival.

Aged

STK11 Mutations and Deletions Define an Aggressive Molecular Subgroup of Cervical Adenocarcinoma.

Cervical adenocarcinoma accounts for 15%-20% of cervical cancers and is associated with poorer survival and reduced response to screening and immunotherapy compared with squamous cell carcinoma (SCC). The genomic drivers underlying this molecular subgroup remain incompletely characterized. Whole-exome sequencing was performed on 302 invasive cervical cancers from Guatemala and Venezuela. Structural variation analysis was conducted using SNP-array and whole-genome sequencing data. Findings were replicated in more than 4600 additional cervical cancer samples from TCGA, AACR Project GENIE, MSKCC, and Caris datasets. TP53 mutations were more frequent in adenocarcinoma than SCC, particularly in HPV-negative tumors. STK11 alterations, including mutations and focal deletions, were significantly enriched in HPV-positive adenocarcinomas compared with SCC and affected 23% of adenocarcinomas overall. Whole-genome analyses identified recurrent focal deletions, inversions, chromosomal rearrangements, and breakage-fusion-bridge events involving chromosome 19p and STK11 that were not detected by exome sequencing alone. STK11 alterations were associated with younger age at diagnosis, poorer overall survival, and inferior outcomes following immune checkpoint inhibitor (ICI) therapy. STK11 alterations significantly co-occurred with YAP1 amplification but were largely mutually exclusive with PIK3CA mutation. Cervical adenocarcinomas also demonstrated significantly lower CD274 (PD-L1) expression than SCC. STK11 alterations define a distinct molecular subgroup of cervical adenocarcinoma characterized by structural disruption of chromosome 19p, younger age at onset, and poorer clinical outcomes. These findings have implications for molecular classification and future targeted therapeutic approaches in cervical cancer.

Humans

Network based approach identifies miR-145-3p as a central regulatory hub associated to the progression from localized to metastatic medullary thyroid carcinoma.

Medullary thyroid carcinoma (MTC) is a neuroendocrine tumor originating from calcitonin producing C-cells and accounts for 1-5% of thyroid cancers. Total thyroidectomy is curative in localized disease (N0), whereas lymph node metastases (N1) are associated with poorer prognosis. However, the molecular mechanisms driving the metastatic shift remain poorly understood. This study aimed to identify miRNA features linked to metastatic spread in MTC, focusing on the transition from N0 to N1. Co-expression networks were constructed for N0 and N1 tumors, and differential connectivity analysis was used to identify key miRNAs acting as regulatory hubs. Functional annotation of their target genes was performed using the Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Ontology (GO), and Reactome pathway analyses. Validation experiments were carried out in MTC cells to evaluate the effects of selected miRNAs on cell proliferation, survival, and MAPK pathway activation. Network analysis revealed distinct miRNA co-expression patterns between N0 and N1 tumors. Differential network analysis highlighted miR-145-3p as a central regulatory hub, exhibiting 29 altered co-expression changes and a marked loss of connectivity in N1. Target enrichment identified 59 validated genes, including key oncogenic drivers such as MYC, PTEN, BCL2, PIK3CA, AKT1, and MAPK7. In MTC cells, simultaneous inhibition of miR-145-3p together with its top co-expressed miRNAs increased proliferation and survival, and enhanced ERK phosphorylation, indicating MAPK pathway activation and a shift toward a more aggressive phenotype. In conclusion, this study identifies a miRNA regulatory hub centered on miR-145-3p that is associated with metastatic progression and highlights the value of network-based approaches in uncovering mechanisms of cancer dissemination. © 2026 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

MAPK signaling

The mechanism of malignant progression in extramammary Paget's disease (EMPD): hallmarks of EMPD.

The pathogenesis of cancer is characterized by the acceleration of tumor growth, inhibition of tumor suppression, genetic and epigenetic alteration, lubricative transformation and tumor microenvironment. Extramammary Paget's disease (EMPD) is a rare skin cancer that originates from apocrine glands in genital and axillary area. Although the pathogenesis of EMPD is still poorly understood, increasing evidence reveals that the mechanism of EMPD progression is regulated by the acquired ability of EMPD cells and tumor microenvironment. HER2/PI3K/AKT signaling and hormone receptor pathways are activated. Whereas tumor mutation burden is low, numerous driver genes such as ERBB2 and PIK3CA are detected. Tumor evolution in EMPD is characterized by high genetic intratumor heterogeneity with shared background factors. Tumor microenvironment in EMPD promotes immune evasion through the reduction of reduced CD4 + and CD8 + T cells and the increase of Treg cells and CD163 + macrophages. Enhanced Warburg effect and S. aureus contribute to the suppression of antitumor immunity. This review focuses on the mechanism of malignant progression in EMPD (hallmarks of EMPD).

Genome mutation

Whole-Genome Deep Learning Predicts Chemotherapy Response in Colorectal Cancer.

Chemotherapy response in colorectal cancer (CRC) exhibits significant heterogeneity, with current clinical predictors failing to capture complex genomic determinants of resistance. We developed a hybrid deep learning framework integrating convolutional neural networks (CNNs) and bidirectional long short-term memory (BiLSTM) networks to analyze whole-genome somatic mutations, evolutionary conservation, chromatin accessibility, and 3D genome architecture in 2,546 TCGA patients. An attention mechanism identified predictive genomic regions. The model achieved an AUC of 0.92 (95% CI: 0.89-0.94) in cross-validation and 0.88 (95% CI: 0.85-0.91) in independent validation, outperforming clinical models (&#x394;AUC = +0.18, p < 0.001). Key predictors included non-coding variants in TP53, KRAS, and PIK3CA regulatory regions. Triple-positive patients (mutations in all 3 regions) had significantly worse progression-free survival (HR = 4.7, p < 0.001). Our framework enables accurate chemotherapy response prediction and reveals novel non-coding resistance mechanisms, advancing precision oncology in CRC.

Humans

Lynch syndrome-associated urothelial carcinoma: clinical and molecular findings from a single-institution cohort.

Lynch syndrome-associated urothelial carcinoma (LS-UC) is a rare and undercharacterized clinical entity. While FGFR3 alterations are well described in sporadic urothelial carcinoma, their prevalence and clinical implications in LS-UC remain unclear. We aimed to provide a comprehensive clinical and molecular characterization of LS-UC. We conducted a retrospective single-center study including patients with Lynch syndrome (LS) and histologically confirmed urothelial carcinoma (UC). Clinical, pathological, treatment, and follow-up data were collected. Targeted next-generation sequencing was performed on available tumor samples to assess genomic alterations, with particular attention to FGFR3 mutations. A total of 27 patients with LS-UC were identified, with a predominance of upper urinary tract involvement (70%). Most tumors were diagnosed at an early stage and initially managed with local treatment. During a median follow-up of 92 months, 48% of patients experienced recurrence, with a median time to recurrence of 37 months. Recurrences were predominantly local and were mainly managed with additional surgical or intravesical treatments. No deaths were attributable to UC at last follow-up. Molecular analysis was feasible in 9 cases. FGFR3 mutations were detected in 67% of evaluable samples, with the recurrent p.Arg248Cys hotspot identified in 55% of cases. Additional alterations involved TP53, SWI/SNF complex genes, and PIK3CA, which co-occurred with FGFR3 p.Arg248Cys. No gene fusions were identified. This study expands the limited molecular and clinical evidence on Lynch syndrome-associated urothelial carcinoma. Beyond confirming the recurrent role of FGFR3 (notably p.Arg248Cys), our comprehensive multigene profiling enriches the current genomic knowledge for this rare population. Multi-center collaborative efforts remain essential to aggregate larger datasets and ultimately guide personalized patient management.

Humans

High Prevalence of Potential Molecular Therapeutic Targets in Poorly Differentiated Thyroid Carcinoma.

Poorly differentiated thyroid carcinoma (PDTC) is a rare thyroid cancer with aggressive clinical course and peculiar clinical/pathological characteristics but lacking effective therapeutic options, when surgery is not curative. We aimed at the molecular characterization of PDTC with a specific focus on the identification of potential therapeutic targets. A series of PDTC cases was selected from a multi-institutional network. Fifty-nine samples underwent wide targeted DNA and RNA next-generation sequencing (NGS) testing and immunohistochemical analysis for mismatch repair (MMR) proteins. Gene fusion analysis was enriched by 25 additional samples. Prevalence of MMR protein loss was 11.9%. The most prevalent mutations were in NRAS (25%) and TP53 (25%), mutually exclusive. TERT promoter (TERTp) mutations were detected in 19.6% of cases (10/51). NRAS-mutated cases were enriched for mutations in genes belonging to the same pathway. TP53-mutated samples lacked TERTp co-mutations, but were associated with mutations in PTEN and in genes related to MMR system and/or loss of MMR proteins. TERTp mutations were the most prevalent alterations (28%, 7/25) in a third group that lacked NRAS or TP53 mutations. Four cases harbored gene fusions, including two cases harboring the TBL1XR1::PIK3CA fusion that has never been reported in thyroid cancer, so far. In conclusion, PDTC may be genomically segregated in subgroups with specific molecular characteristics. Overall, targetable gene fusions have a prevalence of 9% (4/42). Moreover, 47% of cases are potential candidates for individualized target therapies since they harbor mutations in genes coding for potentially targetable molecules and/or have defects in the MMR system.

Humans

A novel lactylation-related gene signature deciphers the immunosuppressive microenvironment and stratifies precision therapy in colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) remains a leading cause of cancer mortality, largely due to the heterogeneity of the tumor microenvironment (TME) and the limited efficacy of immunotherapy in microsatellite stable (MSS) tumors. Histone lactylation, a post-translational modification derived from the Warburg effect, serves as a critical bridge linking metabolic reprogramming to gene regulation and immune evasion; however, its specific prognostic value and clinical implications in CRC remain to be fully elucidated. METHODS: In this study, we systematically analyzed transcriptome profiling data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) cohorts, supplemented by single-cell RNA sequencing (scRNA-seq) analysis and Human Protein Atlas (HPA) protein-level validation. By integrating univariate Cox regression, Least Absolute Shrinkage and Selection Operator (LASSO) analysis, and multivariate Cox regression, we constructed a novel lactylation-related gene (LRG) risk signature. We extensively evaluated the association between this risk signature and patient prognosis, immune infiltration patterns, somatic mutations, and therapeutic sensitivity. RESULTS: A robust 9-gene prognostic signature (DHRS7, SPR, MBD2, RBM17, CSRP2, S100A4, TMSB4X, TKT, COPS4) was identified and corroborated at the protein level. Patients with high risk scores exhibited significantly worse overall survival (OS) across the training and two independent validation cohorts. Immunogenomic and scRNA-seq analyses revealed that high-risk tumors were characterized by an immunosuppressive and stromal-dense microenvironment-with stromal cells exhibiting the highest lactylation risk scores-enriched with regulatory T cells (Tregs), and frequently harbored PIK3CA mutations. Differential expression analysis indicated that this immune exclusion is structurally maintained by enriched extracellular matrix (ECM) organization and TGF-&#x3b2; signaling. Conversely, low-risk tumors displayed an inflamed phenotype with active antitumor immunity. Pharmacogenomic prediction identified distinct therapeutic stratifications: low-risk patients exhibited significant sensitivity to standard chemotherapeutics (fluorouracil, oxaliplatin) and EGFR/HER2 inhibitors (e.g., lapatinib, erlotinib). In contrast, high-risk patients showed specific vulnerabilities to novel targeted agents, including PI3K pathway inhibitors (TG-100-115, XL765), microenvironment-modulating agents (sildenafil, GANT-61), and epigenetic inhibitors (UNC0638). CONCLUSION: We established a novel lactylation-related risk signature that effectively stratifies CRC patients by prognosis and TME characteristics. By elucidating the crosstalk between metabolic dysregulation, stromal barriers, and immune exclusion, this study provides potential biomarkers and stratified therapeutic strategies-ranging from standard chemotherapy to targeted metabolic and stromal interventions-to optimize precision medicine for CRC patients.

Colorectal cancer

The genomic landscape of HER2 negative metastatic breast cancer with loss of estrogen and progesterone receptors.

INTRODUCTION: Loss of estrogen receptor (ER) and/or progesterone receptor (PR) might occur during the metastatic progression of ER positive and HER2 negative (ER+/HER2-) breast cancer (BC), but the underpinning molecular alterations remain elusive. We explored the genomic context of HER2- tumors with ER and/or PR loss to investigate potential drivers and actionable alterations that might help personalize treatment of ER+/HER2- BC. METHODS: We accessed data from metastatic HER2- BC included in the MSK-2018 dataset to compare outcome, tumor characteristics and genomic alterations of BC with loss of ER (ER+/-, n&#xa0;=&#xa0;66) to those maintaining ER positivity (ER+/+, n&#xa0;=&#xa0;364) or ER negativity (ER-/-, n&#xa0;=&#xa0;50). We also compared metastatic ER+/+ BC with loss of PR (PR+/-, n&#xa0;=&#xa0;111) to those maintaining PR positivity (PR+/+, n&#xa0;=&#xa0;192) or PR negativity (PR-/-, n&#xa0;=&#xa0;41). RESULTS: In line with previous reports, ER+/-&#xa0;BC was associated with aggressive clinico-pathological characteristics and poor outcome. ER+/-&#xa0;BC showed significantly higher frequency of TP53 and RB1 mutations and lower frequency of PIK3CA and GATA3 mutations compared to ER+/+. ER+/-&#xa0;or PR+/-&#xa0;status was mutually exclusive with ESR1 mutations and was associated with a significantly higher tumor mutational burden. Moreover, ER+/-&#xa0;BC were enriched in driver alterations in the genes of the Notch and Retinoblastoma pathways and showed a significantly lower frequency of level 1 actionable alterations according to OncoKB. CONCLUSIONS: Loss of ER and/or PR may identify a distinct evolutionary trajectory of ER+/HER2- metastatic progression, largely non-overlapping with ESR1-mutant endocrine resistance. Further studies on matched primary and metastatic samples are warranted.

Humans

Multiregion profiling of genomic and transcriptional heterogeneity in head and neck squamous-cell carcinoma.

BACKGROUND: Intratumoral heterogeneity (ITH) is thought to contribute to tumour evolution and treatment resistance but its biological and clinical significance in localised head and neck squamous-cell carcinoma (HNSCC) remains incompletely understood. PATIENTS AND METHODS: In the prospective SCANDARE study, we analysed 87 patients with resectable HNSCC treated with upfront surgery. Two to five spatially distinct tumour regions per patient underwent pathological evaluation, targeted DNA sequencing, and bulk RNA sequencing. Genomic ITH (gITH) was quantified using clonal deconvolution and Shannon diversity indices, whereas transcriptional heterogeneity (tITH) was assessed using the intratumour expression distance metric. Associations between ITH, molecular features, tumour microenvironment composition, and clinical outcomes were explored using multivariable statistical models. RESULTS: Pathology-based spatial heterogeneity showed limited prognostic value. gITH was common, with 37% of tumours displaying regionally heterogeneous pathogenic variants, including spatially actionable alterations in 10% of patients. In an initial multivariable Cox model, higher gITH was associated with shorter disease-free survival. However, after Ridge-penalised modelling and bootstrap internal validation, the effect size was attenuated [corrected hazard ratio 1.42, 95% confidence interval (CI) 0.91-2.75]. The overall model retained moderate discriminative performance (optimism-corrected C-index 0.69, 95% CI 0.59-0.79). gITH was associated with tumour cellularity, reduced estimated endothelial cell infiltration, and alterations in KMT2C and PIK3CA. tITH differed according to human papillomavirus (HPV) status, with lower tITH in HPV-positive tumours, and was associated with distinct biological pathways and genomic alterations. Genomic and tITH were not correlated. CONCLUSIONS: This prospective multiregion study provides a comprehensive characterisation of genomic and tITH in localised HNSCC. Our findings highlight substantial spatial molecular diversity within primary tumours and suggest potential associations between heterogeneity, tumour biology, and clinical outcome that warrant validation in independent cohorts.

head and neck squamous-cell carcinoma (HNSCC)