CD44: A Multifunctional Mediator of Cancer Progression

CD44, a non-kinase cell surface transmembrane glycoprotein, has been widely implicated as a cancer stem cell (CSC) marker in several cancers. Cells overexpressing CD44 possess several CSC traits, such as self-renewal and epithelial-mesenchymal transition (EMT) capability, as well as a resistance to chemo- and radiotherapy. The CD44 gene regularly undergoes alternative splicing, resulting in the standard (CD44s) and variant (CD44v) isoforms. The interaction of such isoforms with ligands, particularly hyaluronic acid (HA), osteopontin (OPN) and matrix metalloproteinases (MMPs), drive numerous cancer-associated signalling. However, there are contradictory results regarding whether high or low CD44 expression is associated with worsening clinicopathological features, such as a higher tumour histological grade, advanced tumour stage and poorer survival rates. Nonetheless, high CD44 expression significantly contributes to enhanced tumourigenic mechanisms, such as cell proliferation, metastasis, invasion, migration and stemness; hence, CD44 is an important clinical target. This review summarises current research regarding the different CD44 isoform structures and their roles and functions in supporting tumourigenesis and discusses CD44 expression regulation, CD44-signalling pathways and interactions involved in cancer development. The clinical significance and prognostic value of CD44 and the potential of CD44 as a therapeutic target in cancer are also addressed.

Vimentin overexpression as a novel poor prognostic biomarker in eyelid sebaceous gland carcinoma

BackgroundVimentin is an intermediate-sized filament which is highly expressed in mesenchymal cells and is associated with epithelial–mesenchymal transition (EMT). EMT markers ZEB2 and Slug lead to Vimentin overexpression and E-cadherin loss, resulting in invasion and metastasis. However, the status of Vimentin remains unexplored in eyelid sebaceous gland carcinoma (SGC). The study aims to determine status of Vimentin in SGC and its association with EMT markers E-cadherin, ZEB2 and Slug.MethodsVimentin protein expression was undertaken in 66 cases with SGC by immunohistochemistry (IHC). Messenger RNA (mRNA) expression was determined in 42 fresh tissues by quantitative real-time PCR. Association of Vimentin with E-cadherin, ZEB2 and Slug was also analysed. Patients were followed up for 17–69 months (mean 34.02 ± 14.73 months).ResultsIHC revealed Vimentin overexpression in 37/66 (56%) cases. This overexpression showed significant association with lymph node metastasis (p=0.004) and pagetoid spread (p=0.05). Patients with high Vimentin expression also had poor disease-free survival (p=0.033). Univariate Cox regression model indicated that high Vimentin expression (p=0.043) and advanced tumour stage (p=0.002) were independent adverse prognostic factors. High Vimentin mRNA expression was seen in 16/42 (38%) cases and correlated significantly with lymph node metastasis (p=0.027), advanced tumour stage (p=0.002) and large tumour size (p=0.023). Vimentin expression overall showed a significant inverse association with E-cadherin and direct association with ZEB2 expression.ConclusionsVimentin overexpression in SGC is associated with EMT and leads to poor clinical outcome. It also emerged as a novel predictor for lymph node metastasis and poor survival.

Evidence for a delay in diagnosis of Wilms’ tumour in the UK compared with Germany: implications for primary care for children

The UK has a longstanding system of general practice which provides the vast majority of primary care, including that for children. It acts as a 'gatekeeper' to more specialist care. Parents may also use accident and emergency departments as their first point of medical contact for their children. Outcomes in the UK for many conditions in children appear to be worse than in comparable European countries where there is direct access to care by paediatricians. We have therefore looked at pathways to diagnosis and compared outcomes in the childhood kidney cancer, Wilms' tumour, which has been treated in the UK and Germany within the same clinical trial for over a decade. We find that Wilms' tumours are significantly larger in volume and have a more advanced tumour stage at diagnosis in the UK compared to Germany. There is a small (∼3%) difference in event free and overall survival between the two countries. Our data suggest that the system of primary care for children in the UK is less likely to result in the incidental finding of an abdominal mass in a child with no or vague symptoms. This may be a reason for the poorer outcome.

Small intestinal angiosarcoma masquerading as an appendiceal abscess

Angiosarcomas of the small intestine are rare and present non-specifically. They usually manifest with abdominal discomfort, altered bowel habits, anaemia and gastrointestinal bleeding. Diagnosis is often challenging and occurs at an advanced tumour stage. We describe a case of a terminal ileum angiosarcoma masquerading as an appendiceal abscess, and discuss salient clinicopathological features in diagnosing and managing this disease.