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PubMed2026

Early-Onset Colorectal Cancer: Clinical and Molecular Features with Emerging Insights from Comprehensive Genomic Profiling.

Early‑onset colorectal cancer (EOCRC), defined as colorectal cancer (CRC) diagnosed before 50 years of age, is increasing globally. Colorectal cancer is currently the third most commonly diagnosed cancer and the second leading cause of cancer-related death worldwide, with GLOBOCAN 2024 estimating approximately 2.04 million new cases and 917,895 deaths in 2024. Recent studies indicate a sustained rise in EOCRC incidence across multiple regions and birth cohorts, with the greatest increases observed among younger adults. Although hereditary cancer syndromes account for 20-25% of EOCRC cases, most occur in the absence of known genetic predispositions or established risk factors. Emerging evidence implicates the gut microbiome as a potential contributor to EOCRC, with distinct microbial signatures differentiating it from late‑onset colorectal cancer (LOCRC) diagnosed after 50 years of age. This review synthesizes current evidence on clinical, molecular, and diagnostic features distinguishing EOCRC from LOCRC, including differences in anatomical distribution, histopathology, genomic and epigenetic alterations, microbiome composition, and immune landscape, and discusses their implications for personalised screening and therapeutic strategies. We performed a retrospective secondary analysis of comprehensive genomic and immune profiling data from 1737 patients with colorectal cancer tested between June 2021 and June 2023. The analysis showed that tumours arising in patients with EOCRC had lower tumour mutational burden than tumours diagnosed as LOCRC, whereas other immune-related biomarkers, including tumour immunogenicity score, did not remain significantly different after correction for multiple testing. Despite these emerging biological differences, current screening strategies remain largely dependent on an age threshold of 50 years, and EOCRC is not addressed by age‑specific treatment approaches. We therefore review the translational potential of emerging biomarkers, including microbial signatures and liquid biopsy approaches, and propose a framework for integrating molecular profiling into clinical practice. Finally, we highlight the unmet need for coordinated efforts to improve screening in younger populations, address fertility preservation considerations, and ensure adequate psychosocial support for patients with EOCRC.

Early-onset colorectal cancer↗

PubMed2026

Whole genome and exome sequencing of pancreatic neuroendocrine tumour to investigate PRRT response.

Patients with pancreatic neuroendocrine tumours (PNETs) often have similar baseline clinical characteristics, including grade and molecular imaging phenotype, yet have highly variable responses to peptide receptor radionuclide therapy (PRRT). To identify genomic alterations and mutational patterns associated with PRRT treatment response and acquired somatic changes following PRRT exposure, whole genome or exome sequencing was applied to 40 PNET samples from 32 patients, including eight paired pre- or post-PRRT samples. The genomic profile of tumours reflected the known mutational landscape of PNET with MEN1 (34%), ATRX/DAXX (47%) alterations and a recurrent pattern of aneuploidy (38%) detected. A recurrent PSIP1::TBL1X fusion of unknown function was also identified in four tumours. The disease control rate following PRRT using RECIST1.1 and molecular imaging criteria was 88% (28/32). No mutational features were found to be statistically associated with progression-free survival. There was no significant increase in tumour mutational burden in the post-PRRT tumours, nor recurrent emergent mutational changes in cancer driver genes to explain progression to higher-grade disease, when observed. However, a small indel signature (ID8) previously associated with DNA damage repair by non-homologous end joining (NHEJ) was higher in PRRT-exposed compared with PRRT-naive samples (23.8 vs 4.8%, respectively; P < 0.001). Thus, comprehensive DNA analysis of pancreatic NETs did not identify biomarkers predictive of PRRT response nor evidence for high-level PRRT-induced genomic instability or hypermutation, yet mutation signature analysis supports NHEJ as being important for DNA repair and survival of neuroendocrine cells following exposure to beta-particle radiation.

Humans↗

PubMed2026

Long-Term Outcomes and Paired Immune and Genomic Exploratory Analyses After Neoadjuvant Dose-Dense MVAC in Muscle-Invasive Bladder Cancer: A Single-Centre Case Series.

Background/Objectives: Cisplatin-based neoadjuvant chemotherapy (NAC) followed by radical cystectomy has been the standard of care for muscle-invasive bladder cancer (MIBC) for two decades, yet a substantial proportion of patients derive no benefit. As antibody-drug conjugates and immune checkpoint inhibitors reshape perioperative treatment, it is unclear which patients retain meaningful benefit from platinum. We describe long-term outcomes and exploratory paired immune and genomic analyses in a single-centre cohort treated with dose-dense MVAC (dd-MVAC). Methods: We retrospectively identified 54 consecutive patients with MIBC treated with neoadjuvant dd-MVAC between November 2013 and November 2019. Forty-two underwent radical cystectomy and are assessable for pathologic response. Immunohistochemistry for CD3, CD8, FOXP3, PD-1, PD-L1, PD-L2, and NY-ESO-1 was evaluable in 31 baseline specimens and 22 paired specimens; paired genomic profiling was evaluable in 12 cases, with paired tumour mutational burden (TMB) in 10 by whole-exome sequencing and 7 by TSO-500. Paired analyses necessarily exclude patients achieving a pathologic complete response (pCR), who have no residual tumour, and most early progressors. Results: pCR was achieved in 11/42 operated patients (26%, 95% CI 15-41). Median follow-up was 87 months (IQR 24-104). Hydronephrosis was the only baseline factor associated with absence of pCR (p = 0.016). Within the operated cohort, pCR was associated with longer recurrence-free survival (log-rank p = 0.017), but the difference in overall survival did not reach significance (p = 0.121). NAC reduced intratumoral FOXP3 (q = 0.001), NY-ESO-1 (q = 0.013), PD-L2 (q = 0.013), and CD3 (q = 0.043) after correction for multiple comparisons, whereas TMB showed no significant change (TSO-500 p = 0.67; WES p = 0.86). No statistically significant association was detected between any baseline immune marker, including PD-L1, and pCR. The mutational landscape was largely concordant before and after NAC. Conclusions: This study was exploratory and was not powered to validate predictive biomarkers. In this long-term cohort, dd-MVAC was associated with measurable depletion of intratumoral immune populations in chemoresistant tumours, while paired genomic profiles remained broadly concordant. No pre-treatment biomarker identified platinum-refractory patients, but the small evaluable subsets mean these are hypothesis-generating rather than negative findings, and prospective studies with pre-specified biomarker endpoints are required.

chemoresistance↗

PubMed2021

Immune biomarkers and response to checkpoint inhibition of BRAFV600 and BRAF non-V600 altered lung cancers.

BACKGROUND: While 2-4% of lung cancers possess alterations in BRAF, little is known about the immune responsiveness of these tumours. METHODS: Clinical and genomic data were collected from 5945 patients with lung cancers whose tumours underwent next-generation sequencing between 2015 and 2018. Patients were followed through 2020. RESULTS: In total, 127 patients with metastatic BRAF-altered lung cancers were identified: 29 tumours had Class I mutations, 59 had Class II/III alterations, and 39 had variants of unknown significance (VUS). Tumour mutation burden was higher in Class II/III than Class I-altered tumours (8.8 mutations/Mb versus 4.9, P < 0.001), but this difference was diminished when stratified by smoking status. The overall response rate to immune checkpoint inhibitors (ICI) was 9% in Class I-altered tumours and 26% in Class II/III (P = 0.25), with median time on treatment of 1.9 months in both groups. Among patients with Class I-III-altered tumours, 36-month HR for death in those who ever versus never received ICI was 1.82 (1.17-6.11). Nine patients were on ICI for >2 years (two with Class I mutations, two with Class II/III alterations, and five with VUS). CONCLUSIONS: A subset of patients with BRAF-altered lung cancers achieved durable disease control on ICI. However, collectively no significant clinical benefit was seen.

Biomarkers, Tumor↗

PubMed2026

Landscape of genetic alterations affecting cancer genes in primary and advanced malignant phyllodes tumours.

BACKGROUND: Malignant phyllodes tumours (MPT) are aggressive breast fibroepithelial neoplasms. Their rarity has limited their genetic characterization, and associations with genetic ancestry and progression drivers remain poorly understood. Prior studies suggest two evolutionary pathways according to MED12 mutational status. We sought to determine the repertoire of somatic genetic alterations in cancer genes in primary versus metastatic/recurrent MPTs, and according to MED12 mutational status and genetic ancestry. MATERIALS AND METHODS: We analysed the paired tumour-normal targeting sequencing data (up to 505 cancer-related genes) of 31 MPTs (primary, n = 20; metastatic/recurrent, n = 11). RESULTS: Metastatic/recurrent MPTs harboured a numerically higher frequency of genetic alterations in CDKN2A/2B (55% vs. 25%). Moreover, analysis of an MPT case with paired primary and metastatic samples revealed a CDKN2A/2B homozygous deletion restricted to the metastatic sample, suggesting a role for CDKN2A/2B in progression. Compared with MED12-wild type MPTs, MED12-mutant MPTs had higher tumour mutation burden (P = 0.002), frequency of TERT promoter (82% vs. 35%; P = 0.02) and RB1 mutations (45% vs. 5%; P = 0.01). Genetic alterations in the PI3K pathway, including PIK3CA and PTEN, were only present in MED12-wild type MPTs, and absent in MED12-mutant cases (15% vs. 0%; P > 0.05). Furthermore, genetic alterations in EGFR were restricted to MPTs from patients of European genetic ancestry and absent in those of Asian ancestry (43% vs. 0%; P > 0.05). CONCLUSIONS: Taken together, the repertoire of genetic alterations in primary and metastatic/recurrent MPTs shows overlap, and CDKN2A/2B homozygous deletions may play a role in progression. Additionally, molecular profiles of MPTs may vary according to genetic ancestry and MED12 mutational status.

Humans↗

PubMed2026

Survey of diagnostic laboratories highlights need for improved standards in somatic genomic testing and reporting.

There is a growing international need to support somatic genomic testing, standardised variant curation and improved patient access to molecular profiling for somatic conditions, including cancer. We conducted a survey of scope, curation, reporting and sharing practices of diagnostic laboratories performing somatic testing in Australia and New Zealand. Laboratories with accreditation (n = 41) were invited in 2023 to complete a semi-structured, 25-question interview. Responses were received for 27 laboratories (66% response rate) offering solid tumour, haematological malignancy and non-cancer services. Only 36% of laboratories offered tests capturing the full breadth of variants, from single-nucleotide variants to gene fusions. Knowledge sharing was rare, with only one laboratory submitting variant classifications to a public knowledge base. Most laboratories (96%) conducted somatic testing in oncology. Of cancer laboratories, 35% offered testing considered capable of comprehensive genomic profiling (CGP). Almost half of cancer laboratories had already adopted the 2022 ClinGen/CGC/VICC oncogenicity guidelines, and 84% were using AMP/ASCO/CAP 2017 clinical significance guidelines. Only 47% of mixed discipline cancer laboratories reported biomarkers such as tumour mutational burden, with wide variation in reporting of matched therapy options. Our study has generated a unique overview of somatic laboratory practices in the region, and areas for global standardisation in somatic molecular testing and reporting. We also provide a model for practice and guideline uptake assessment, for application by other country-wide networks. This is particularly relevant in anticipation of CGP mainstreaming, with the increasing complexity of sequencing interpretation for laboratories and clinicians.

Humans↗

PubMed2025

A novel glycogene-related signature for prognostic prediction and immune microenvironment assessment in kidney renal clear cell carcinoma.

BACKGROUND: Kidney Renal Clear Cell Carcinoma (KIRC) is a prevalent urinary malignancies worldwide. Glycosylation is a key post-translational modification that is essential in cancer progression. However, its relationship with prognosis, tumour microenvironment (TME), and treatment response in KIRC remains unclear. METHOD: Expression profiles and clinical data were retrieved from The Cancer Genome Atlas and Gene Expression Omnibus databases. Consensus clustering, Cox regression, and LASSO regression analyses were conducted to develop an optimal glycogene-related signature. The prognostic relevance of this molecular signature was rigorously analyzed, along with its connections to tumour microenvironment (TME), tumour mutation burden, immune checkpoint activity, cancer-immunity cycle regulation, immunomodulatory gene expression patterns, and therapeutic response profiles. Validation was performed using real-world clinical specimens, quantitative PCR (qPCR), and immunohistochemistry (IHC), supported by cohort analyses from the Human Protein Atlas (HPA) database. RESULTS: A glycogene-associated prognostic scoring system was established to categorize patients into risk-stratified subgroups. Patients in the high-risk cohort exhibited significantly poorer survival outcomes (p < 0.001). By incorporating clinicopathological variables into this framework, we established a predictive nomogram demonstrating strong calibration and a concordance index (C-index) of 0.78. The high-risk subgroup displayed elevated immune infiltration scores (p < 0.001), upregulated expression of immune checkpoint-related genes (p < 0.05), and an increased frequency of somatic mutations (p = 0.043). The risk score positively correlated with cancer-immunity cycle activation and immunotherapy-related signals. The high-risk groups also showed associations with T cell exhaustion, immune-activating genes, chemokines, and receptors. Drug sensitivity analysis revealed that low-risk patients were more sensitive to sorafenib, pazopanib, and erlotinib, whereas high-risk individuals responded better to temsirolimus (p < 0.01). qPCR and IHC analyses consistently revealed distinct expression patterns of MX2 and other key genes across the risk groups, further corroborated by the HPA findings. CONCLUSION: This glycogene-based signature provides a robust tool for predicting prognosis, TME characteristics, and therapeutic responses in KIRC, offering potential clinical utility in patient management.

Humans↗

PubMed2025

Molecular features influencing clinical outcome of advanced HER2-positive gastric cancer receiving trastuzumab plus chemotherapy.

BACKGROUND: Less than half of the human epidermal growth factor receptor 2 (HER2)-positive gastric cancer (GC) patients respond to trastuzumab plus chemotherapy, and the outcomes are unsatisfactory. Understanding the underlying mechanisms remains crucial for identifying patients who are more likely to benefit from treatment. PATIENTS AND METHODS: We performed targeted DNA sequencing on paired pre-treatment and progressive tumour tissues from 22 HER2-positive advanced GC patients undergoing first-line treatment with trastuzumab and chemotherapy. Clinicopathological and genomic characteristics were assessed for the correlation with clinical outcomes. RESULTS: A performance status (PS) of 0-1 was associated with improved progression-free survival (PFS) and overall survival (OS) than a PS of 2. Poorly differentiated tumours exhibited shorter PFS than moderate or moderate-poor ones. Pre-treatment amplification of MYC or TOP2A gene was association with increased PFS, and suggested a potential benefit for OS. Patients with higher tumour mutation burden (TMB) experienced significantly worse PFS, while higher chromosome instability (CIN) appeared to be correlated with longer PFS. Compared to non-responders, responders had a higher CIN but similar TMB and intratumoural heterogeneity (ITH). PS and MYC amplification emerged as independent factors related to PFS according to multivariate survival analysis. Additionally, after treatment, TMB significantly increased in non-responders, while CIN significantly decreased in responders. CONCLUSIONS: Pre-treatment MYC amplification and PS were independently associated with clinical outcomes in HER2-positive advanced GC patients treated with first-line trastuzumab plus chemotherapy. Dynamic post-treatment changes in TMB and CIS provide valuable insights into the relationship between therapeutic response and distinct evolutionary trajectories.

Humans↗

PubMed2006

Somatic hypermutation and VH gene usage in hairy cell leukaemia.

To examine the usage and mutational status of VH genes in hairy cell leukaemia (HCL), we analysed 24 immunoglobulin heavy chain (IgH) sequences expressed in 23 patients. None had premature stop codons. VH3-23 was the most common gene and a VH6 gene was observed for the first time in HCL. Although the mean mutation frequency was 6.1%, slightly higher than in previous HCL series, four patients had 99.6-100% homology to germline sequences, three of whom had high tumour burdens and poor outcomes. Despite the high mutation frequency, only two of 24 rearrangements had clear statistical evidence of antigen-dependent somatic mutation. Our results increase the database of reported functional HCL rearrangements to 94 in 92 patients. Overall, both gene usage and mutation frequency are very similar to mucosa-associated lymphoid tissue-type marginal zone lymphoma. The data are consistent with HCL originating from post-germinal centre marginal zone B cells, although the heterogeneity observed suggests that HCL may originate differently in some patients, and this could have implications for prognosis and treatment.

Base Sequence↗

PubMed2025

Single-cell mutational burden distributions in birth-death processes.

Genetic mutations are footprints of cancer evolution and reveal critical dynamic parameters of tumour growth, which otherwise are hard to measure in vivo. The mutation accumulation in tumour cell populations has been described by various statistics, such as site frequency spectra (SFS), single-cell division distributions (DD) and mutational burden distributions (MBD). While DD and SFS have been intensively studied in phylogenetics especially after the development of whole genome sequencing technology of bulk samples, MBD has drawn attention more recently with the single-cell sequencing data. Although those statistics all arise from the same somatic evolutionary process, an integrated understanding of these distributions is missing and requires novel mathematical tools to better inform the ecological and evolutionary dynamics of tumours. Here we introduce dynamical matrices to analyse and unite the SFS, DD and MBD and derive recurrence relations for the expectations of these three distributions. While we successfully recover classic exact results in pure-birth cases for the SFS and the DD through our new framework, we derive a new expression for the MBD and approximate all three distributions when death is introduced. We demonstrate a natural link between the SFS and the single-cell MBD, and show that the MBD can be regenerated through the DD. Counter-intuitively, the single-cell MBD is mainly driven by the stochasticity arising in the DD, rather than the extra stochasticity in the number of mutations at each cell division.

Single-Cell Analysis↗

PubMed2026

Integration of multi-omics data uncovers novel germline susceptibility candidates in early-onset colorectal cancer.

Colorectal cancer (CRC) is increasingly diagnosed in individuals under 50 years of age, yet the underlying genetic predisposition remains largely unexplained, particularly in mismatch repair (MMR)-proficient cases. This study aimed to identify novel hereditary CRC susceptibility genes by integrating germline and tumour whole-exome sequencing (WES) with transcriptomic profiling across a cohort of early-onset CRC (EOCRC) patients. Tumours were categorised using Consensus Molecular Subtypes (CMS) classification and analysed for mutational signature and burden. We used a novel 'All vs One' multi-omic integration approach to identify loss-of-function rare germline variants with concordant gene expression alterations in tumour tissue. Five candidate genes (ADCY4, NOXO1, CDHR2, ARHGAP10, EEF2K) were prioritised based on this approach and potential biological relevance in CRC. These findings highlight the molecular heterogeneity of EOCRC and demonstrate the utility of multi-omic approaches in refining germline variant interpretation. Integrating tumour transcriptomics enhances gene discovery efforts and supports a more comprehensive understanding of CRC heritability in younger individuals.

Humans↗

PubMed1997

Detection of tumour DNA in serum of colorectal cancer patients.

Circulating tumour DNA has previously been detected in serum and plasma of patients with lung cancer and head and neck cancer. These observations could potentially lead to new, specific and non-invasive tools for diagnosis, prognosis and follow-up in neoplastic disease, if found to be a more general phenomenon. To test if tumour DNA is also present in serum of patients with colorectal cancer, we selected 14 colorectal cancer patients with advanced disease. In seven patients, K-ras mutations were detected in the primary tumour, using mutant-specific primers for point mutations in codon 12 or 13 of the K-ras gene. All patients were analysed for mutant DNA in serum. Tumour-specific point mutations, corresponding to the K-ras mutations found in the primary tumour were detected in the serum of all patients but one. No mutant K-ras could be detected in the serum of seven patients without K-ras mutations in the primary tumour. These results may be useful in assessing tumour burden in patients with neoplastic disease. Moreover, consecutive testing of serum tumour DNA after surgery or chemotherapy may be used as a tumour marker for recurrent disease.

Colorectal Neoplasms↗

PubMed1997

Apoptosis and carcinogenesis.

Many tumours are characterised by increased levels of apoptosis. This observation establishes significance for this process in tumour development, but it does little to elucidate the nature of this role, nor does it yield information relevant to the early stages of carcinogenesis. To gain a better understanding of the importance of apoptosis, it has been necessary to create a number of transgenic model systems wherein the apoptotic response has been modified. Using this strategy, a number of genetic lesions have been identified which affect both the apoptotic pathway and predisposition to malignancy. These lesions can operate either directly, by blocking the induction of apoptosis; or indirectly, by increasing the selective pressure for further genetic change. The consequent deregulation of growth control and increase in mutation burden represent two key steps in carcinogenesis, underlining the pivotal role played in tumour suppression by the normal induction of apoptosis.

Apoptosis↗

PubMed1995

The proliferation of multiple myeloma colonies (MY-CFUc) in vitro is independent of prognosis and is not associated with mutated N- or K-ras alleles in human bone marrow aspirates.

During the period September 1987 to March 1993 the proliferation of myeloma cells as colonies (MY-CFUc) in vitro was examined in bone marrow aspirates from 43 patients with multiple myeloma and two patients with Waldenström's macroglobulinaemia. Twenty-four samples from 45 patients, of whom three were at presentation, four were in complete remission (CR), six had achieved a partial response (PR) and 11 had progressive disease (PD), produced MY-CFUc in vitro. The same bone marrow aspirates or one taken within 2 months of that assessed for MY-CFUc were used in the polymerase chain reaction (PCR). Genomic DNA was analysed for mutations in N- and K-ras by slot blotting of the amplified products from the PCR with 32P-labelled probes and by direct sequencing. No mutations were detected in N- or K-ras proto-oncogenes at codons 12, 13 or 61 in any sample. Eleven of the patients from whom MY-CFUc were produced remain alive with a median survival of 73 months (range 15-75 months). MY-CFUc have been cultured from 19 of these 24 patients on subsequent occasions, of whom nine remain alive. Among patients whose cells did not produce MY-CFUc in vitro at the time of sampling for mutated ras alleles, biopsy samples from four patients have produced MY-CFUc in vitro on subsequent occasions, of whom one patient remains alive. The data show that the proliferation of MY-CFUc in vitro occurred independently of disease status and was not indicative of prognosis. The failure to detect mutated N- or K-ras alleles in any sample suggests that if such mutations were present in the cells which form colonies in vitro they represented less than 0.1% of the tumour burden and did not affect the survival of this group of patients.

Alleles↗

PubMed2026

Solid tumours in RASopathies: insights from a large monocentric cohort and systematic review of the literature.

BACKGROUND: Dysregulation of the RAS-mitogen-activated protein kinase signalling pathway underlies RASopathies, a family of neurodevelopmental disorders associated with variable cancer predisposition. However, the prevalence and spectrum of solid tumours and the contribution of specific variants to tumour susceptibility remain poorly defined. METHODS: We assessed solid tumour prevalence and spectrum in the largest single-centre cohort of individuals with RASopathies (n=138), excluding neurofibromatosis type 1 and integrated these findings with a systematic literature review to evaluate tumour distribution and genotype-phenotype correlations. RESULTS: In our cohort, at least one solid tumour was identified in 10.8% of individuals with Noonan syndrome (NS), 47.8% with Costello syndrome (CS) and 7.3% with cardiofaciocutaneous syndrome (CFCS). Malignant tumours occurred in 5.4%, 30.4% and 2.4%, respectively. CS showed the highest tumour burden, frequently with multiple primary tumours, predominantly of the bladder. In NS, low-grade central nervous system (CNS) tumours were most common, particularly among individuals carrying PTPN11 variants. Tumour onset occurred with a median age of 19, 14 and 13 years in NS, CS and CFCS, respectively. Literature data analysis identified candidate variants in HRAS, PTPN11 and SOS1 genes associated with increased risk for solid tumours, which differed from mutational hotspots reported in childhood leukaemia or sporadic cancers. CONCLUSION: Solid tumour risk in RASopathies is syndrome-dependent and genotype-dependent, with CS showing a high burden of bladder tumours and NS mainly associated with CNS tumours. These findings may support tailored surveillance strategies.

Human Genetics↗

PubMed2026

Evolution and heterogeneity of lethal metastatic bladder cancer subtypes.

Histological variation is a prognostic feature of metastatic urothelial cancer1-3, but its evolutionary trajectory remains poorly defined. We developed a metastatic bladder cancer rapid autopsy programme enriched in histological subtypes4 to profile individuals with terminal disease. Here by reconstructing the evolutionary histories of patient tumours, we show that metastasis-to-metastasis seeding is the dominant pattern of cancer spread and that increased polyclonal migration predicts poor prognosis. The burden, heterogeneity and timing of genomic alterations differ markedly among histological subtypes. Plasmacytoid and neuroendocrine variants develop early driver alterations associated with shorter survival. Mutational signature analyses and experimental models demonstrated that plasmacytoid tumours uniquely use the Fanconi anaemia pathway to mitigate chemotherapy-induced genomic scarring. Single-nucleus profiling revealed mixed cell states in histological subtypes and an association between transcriptional heterogeneity and patient survival. Characterization of the tumour microenvironment uncovered distinct immune states across subtypes, with plasmacytoid tumours exhibiting immune-inflamed profiles, whereas squamous tumours are predominantly immunosuppressive. Last, we demonstrate that post-mortem cell-free DNA captures genomic and transcriptional heterogeneity of the subtypes, which provides a potential strategy for noninvasive assessment of tumour identity and aggressiveness. Our results provide new insights into how tumour heterogeneity shapes the evolutionary history of disease progression in bladder cancer histological subtypes.

Journal Article↗

PubMed1997

p53 mutation spectrum in Japanese Bowen's disease suggests a role for mutagens other than ultraviolet light.

The Japanese have a much lower incidence of nonmelanoma skin cancers (NMSCs) than Caucasians, presumably due in part to their skin type conferring relative protection from ultraviolet light radiation (UVR). To examine the contribution of environmental or endogenous mutagens other than UVR, which are expected to be relatively more important to the overall burden of NMSCs in the Japanese, we directly sequenced exons 5-8 of the p53 tumour suppressor gene in 29 Japanese patients with Bowen's disease, an in situ squamous-cell carcinoma of the skin. We found 9 mutations, including two CC:GG to TT:AA tandem transitions (presumably related to UVR), 3 transversions and 4 frameshift mutations. The mutational spectrum seen in our study contrasts with that we previously found in Bowen's disease from a Caucasian population, in keeping with a different aetiology for Bowen's disease in the respective populations. The unexpectedly high prevalence of frameshift mutations suggests that environmental mutagens other than UVR that preferentially induce deletion or insertion mutations may play an important role in the tumorigenesis of Japanese Bowen's disease, and warrants further investigation.

Aged↗

PubMed2005

Earliest clinical manifestations and natural history of neurofibromatosis type 2 (NF2) in childhood: a study of 24 patients.

BACKGROUND: Neurofibromatosis type 2 (NF2) is an autosomal dominant disease characterised by the development of multiple nervous system tumours, ocular abnormalities, and skin tumours. Although classically considered a disease of adults, initial signs and/or symptoms may be evident in childhood and are often unrecognised. OBJECTIVES: The aim of this study was to identify the earliest clinical presentations of NF2 and to characterise the clinical course and outcome in children with NF2. METHODS: We have performed a retrospective (years 1990-1998) and prospective (years 1998-2004) study of 24 patients (10 males, 14 females; currently aged 4 to 22 years) fulfilling the revised (Manchester) NF2 criteria seen at the Universities of Catania and Rome, Italy. RESULTS: Causes of referral prior to a definitive diagnosis of NF2 were: 1) Ophthalmologic problems: early onset lens opacities (n = 3); strabismus (n = 3) and amblyopia (n = 3) (due to underlying cranial nerves and/or brain tumours); 2) Otolaryngology problems: hearing loss and tinnitus (n = 2) in early teens disregarded or treated as ear infections; hoarse (n = 1) or bitonal (n = 1) voice; 3) Neurological dysfunction: seizures secondary to intracranial meningioma (n = 1) or vestibular schwannomas (VS) (n = 1), neurological dysfunction related to brainstem and/or spinal cord tumours (n = 7), isolated and multiple cranial nerve deficits (n = 10), and peripheral neuropathy secondary to schwannomas (n = 4); 4) Skin manifestations: schwannomas misdiagnosed as neurofibromas because of associated café-au-lait spots (n = 2); café-au-lait spots (n = 8) and skin tumours (n = 3). A family history was relevant in 20 % of the patients. Molecular genetic analysis of the NF2 gene revealed typical truncating mutations in all the 5 familial cases and in 2/10 sporadic cases analysed. CONCLUSIONS: Children with NF2 often first come to medical attention because of ocular, subtle skin, or neurological problems the significance of which is realised when they later present with more classical symptoms due to bilateral VS or other intracranial tumours. The clinical course at this young age is highly variable, depending on tumour burden, early surgical intervention, surgical outcome after tumour resection, and complications.

Adolescent↗