Karwan Moutasim

Dr. Karwan Moutasim

Department of Cellular Pathology, University Hospital Southampton NHS Foundation Trust, Southampton, UK
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Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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30 April 2019 in The Journal of Pathology: Clinical Research
Verified
Journal Article
Open access
PDF file
KPKate Packwood
Kate Packwood
GMGuy Martland
Guy Martland
MSMatthew Sommerlad
Matthew Sommerlad
ESEmily Shaw
Emily Shaw
KMKarwan Moutasim
Karwan Moutasim
DEDiana M Eccles
Diana M Eccles
Germline TP53 pathogenic variants are rare but associated with a high risk of cancer; they are often identified in the context of clinically diagnosed Li–Fraumeni syndrome predisposing to a range of young onset cancers including sarcomas and breast cancer. The study aim was to conduct a detailed morphological review and immuno‐phenotyping of breast cancer arising in carriers of a germline TP53 pathogenic variant. We compared breast cancers from five defined groups: (1) TP53 carriers with breast cancer (n = 59), (2) early onset HER2‐amplified breast cancer, no germline pathogenic variant in BRCA1/2 or TP53 (n = 55), (3) BRCA1 pathogenic variant carriers (n = 60); (4) BRCA2 pathogenic variant carriers (n = 61) and (5) young onset breast cancer with no known germline pathogenic variant (n = 98). Pathologists assessed a pre‐agreed set of morphological characteristics using light microscopy. Immunohistochemistry (IHC) for HER2, ER, PR, p53, integrin alpha v beta 6 (αvβ6) integrin, α‐smooth muscle actin (α‐SMA) and pSMAD2/3 was performed on tissue microarrays of invasive carcinoma. We confirmed a previously reported high prevalence of HER2‐amplified, ductal no special type invasive breast carcinoma amongst known TP53 germline pathogenic variant carriers 20 of 36 (56%). Furthermore we observed a high frequency of densely sclerotic tumour stroma in cancers from TP53 carriers (29/36, 80.6%) when compared with non‐carriers, 50.9% (28/55), 34.7% (50/144), 41.4% (65/157), 43.8% (95/217) in groups 2–5 respectively. The majority of germline TP53 gene carrier breast tumours had a high intensity of integrin αvβ6, α‐SMA and pSMAD2/3 expression in the majority of cancer cells. In conclusion, aggressive HER2 positive breast cancers with densely sclerotic stroma are common in germline TP53 carriers. High levels of αvβ6 integrin, α‐SMA and pSMAD2/3 expression suggest that the dense stromal phenotype may be driven by upregulated transforming growth factor beta signalling.

1 April 2020 in Diagnostic Histopathology
Verified
Journal Article
Open access
KMKarwan Moutasim
Karwan Moutasim
Gareth ThomasGareth Thomas
Gareth Thomas

13 October 2020 in Cancers
Verified
Journal Article
Open access
PDF file
JFJason Fleming
Jason Fleming
JWJeongmin Woo
Jeongmin Woo
KMKarwan Moutasim
Karwan Moutasim
CHChristopher Hanley
Christopher Hanley
SFSteven J. Frampton
Steven J. Frampton
Gareth ThomasGareth Thomas
Gareth Thomas
Head and neck squamous cell carcinoma (HNSCC) is a heterogenous disease treated with surgery and/or (chemo) radiotherapy, but up to 50% of patients with late-stage disease develop locoregional recurrence. Determining the mechanisms underpinning treatment resistance could identify new therapeutic targets and aid treatment selection. C-terminal tensin-like (CTEN) is a member of the tensin family, upregulated in several cancers, although its expression and function in HNSCC are unknown. We found that CTEN is commonly upregulated in HNSCC, particularly HPV−ve tumours. In vitro CTEN was upregulated in HPV−ve (n = 5) and HPV+ve (n = 2) HNSCC cell lines. Stable shRNA knockdown of CTEN in vivo significantly reduced tumour growth (SCC-25), and functional analyses in vitro showed that CTEN promoted tumour cell invasion, colony formation and growth in 3D-culture (SCC-25, Detroit 562). RNA sequencing of SCC-25 cells following CTEN siRNA knockdown identified 349 differentially expressed genes (logFC > 1, p < 0.05). Gene ontology analysis highlighted terms relating to cell locomotion and apoptosis, consistent with in vitro findings. A membrane-based antibody array confirmed that CTEN regulated multiple apoptosis-associated proteins, including HSP60 and cleaved caspase-3. Notably, in a mixed cohort of HPV+ve and HPV−ve HNSCC patients (n = 259), we found a significant, independent negative association of CTEN with prognosis, limited to those patients treated with (chemo)radiotherapy, not surgery, irrespective of human papillomavirus (HPV) status. These data show that CTEN is commonly upregulated in HNSCC and exerts several functional effects. Its potential role in modulating apoptotic response to therapy suggests utility as a predictive biomarker or radio-sensitising target.

1 January 2009 in International Archives of Medicine
Verified
Journal Article
Open access
PDF file
KMKarwan Moutasim
Karwan Moutasim
PSPenelope J Shirlaw
Penelope J Shirlaw
MEMichael P Escudier
Michael P Escudier
TPTimothy Wj Poate
Timothy Wj Poate
Congenital heart block is a rare complication of pregnancy associated with Sjögren Syndrome that may result in the death of the foetus or infant, or the need for pacing in the newborn or at a later stage.

25 October 2025 in Bioengineering
Verified
Journal Article
Open access
PDF file
Boyang YuBoyang Yu
Boyang Yu
HMHannah Markham
Hannah Markham
KMKarwan Moutasim
Karwan Moutasim
VFVipul Foria
Vipul Foria
HLHaiming Liu
Haiming Liu
In histopathological image segmentation, existing methods often show low sensitivity to small lesions and indistinct boundaries, leading to missed detections. Since, in clinical diagnosis, the consequences of missed detection are more serious than false alarms, this study proposes ClinSegNet, a recall-oriented and human-centred framework for reliable histopathology screening. ClinSegNet employs a composite optimisation strategy, termed HistoLoss, which balances stability and boundary refinement while prioritising recall. An uncertainty-driven refinement mechanism is further introduced to target high-uncertainty cases with limited fine-tuning cost. In addition, a clinical data processing pipeline was developed, where pixel-level annotations were automatically derived from IHC-to-H&E mapping and combined with public datasets, enabling effective training under limited clinical data conditions. Experiments on the NuInsSeg and NuInsSeg-UHS datasets showed that ClinSegNet achieved recall scores of 0.8803 and 0.8917, further improved to 0.8983 and 0.9053 with HITL refinement, while maintaining competitive Dice and IoU. Comparative and ablation studies confirmed the complementary design of the framework and its advantage in capturing small or complex lesions. In conclusion, ClinSegNet provides a clinically oriented, recall-prioritised framework that enhances lesion coverage, reduces the risk of missed diagnosis, and offers both a methodological basis for future human-in-the-loop systems and a feasible pipeline for leveraging limited clinical data.

17 October 2024 in Head and Neck Pathology
Verified
Journal Article
Closed access
PDF file
GDGrace Dimbleby
Grace Dimbleby
ARAlessandro Rettino
Alessandro Rettino
SJSanjay Jogai
Sanjay Jogai
SHSathish Harinayanan
Sathish Harinayanan
NPNimesh Patel
Nimesh Patel
KMKarwan Moutasim
Karwan Moutasim