Analysis of CD44 isoform v10 expression and its prognostic value in renal cell carcinoma

Abstract

Objective To examine the expression of CD44 isoform v10 (CD44v10) in patients with renal cell carcinoma (RCC), analyse its role in RCC and its relationship with conventional clinical-histopathological experience. Materials and methods Sixty-four RCC specimens and ®ve metastatic specimens were analysed immunohistochemically using a CD44v10 speci®c antibody. Thus the aims of the present study were to examine the correlation between the immunohistochemical expression of CD44v10 protein with conventional histopathological variables and to determine its prognostic role in patients with RCC. Materials and methodsSamples of tumour and normal foci were obtained from 64 patients (41 men and 23 women, mean age 62 years, range 23±79) with RCC who underwent radical nephrectomy. The tissue was formalin-®xed and paraf®n-embedded. The clinicopathological characteristics of tumours from all patients were classi®ed according to the general rules for clinical and pathological studies of RCC of the Japanese Urological Association and Society of Pathology (Table 1). Five metastatic lesions from the patients with RCC were also analysed, including three lymph node metastasis, one bone metastasis and one skin metastasis. The median (range) follow-up of the patients was 48.6 (2.6±105) months. Immunohistochemical stainingSections (5 mm) were stained immunohistochemically using primary antibodies directed against CD44v10 protein (Clone VFF-14, Serotec Ltd, Oxford, England, dilution 1 : 100). The procedure was modi®ed slightly from that described previously [25]. Sections were deparaf®nized in xylene and rehydrated in graded alcohols, and then autoclaved in citrate buffer for 10 min at 120uC and allowed to cool at room temperature for 40 min. Endogenous peroxidase activity was blocked by immersing sections in 0.3% hydrogen peroxide in methanol for 30 min before immunostaining. Sections were pretreated with normal rabbit serum for 5 min at room temperature and incubated overnight at 4uC with the primary antibodies in a humidi®ed chamber. Subsequently, biotinylated antirabbit and antimouse antibody (LSAB-Kit, Dako Corp., Carpinteria, CA, USA) was applied to the sections for 10 min. Streptavidin-biotinylated peroxidase complex (LSAB-Kit, Dako) was then applied and sections incubated with the chromogen diaminobenzidine (Wako, Osaka, Japan). After immunohistochemical staining, sections were counterstained with haematoxylin to enhance nuclear detection. Between all antibody incubations, sections were washed with PBS. Finally, slides were dehydrated and mounted in Permount. For the negative controls, primary antibody was substituted with PBS in duplicate sections.CD44v10 expression was evaluated using light microscopy, with cells that stained darker than the negative controls considered positive. The percentage of tumour cells positively stained was determined by counting at least 800 tumour cells in four selected ®elds that showed the highest immunoreactivity at r400 magni®cation. The immunohistochemical results were evaluated as: negative, no ...

Prognostic value of CD44 expression in renal cell carcinoma: a systematic review and meta-analysis

“…Two studies focused on CD44v5 expression, and only one study concluded that the CD44v5 non-expression group has a higher mortality rate than the expression group 24 25 . One study with CD44v10 demonstrated that high CD44v10 expression correlates with high tumour grade, clinical stage and short survival 26 . The expression of CD44v3 was not detected in one study 22 .…”

“…Similarly, CD44v3 positive rate is also very low in one study 22 . Another study reported that CD44v10 expression significantly correlates with histological grade, clinical and pathological stages and cancer-specific survival 26 . Two studies obtained significantly different results on the expression rates (91.7% and 6.4%) of CD44v5 24 25 .…”

CD44 variant isoforms in head and neck squamous cell carcinoma progression

“…CD44 v6 overexpression has been correlated with advanced tumor stage and poor survival in non‐Hodgkin's lymphoma and colon cancer 20. CD44 v10 correlation with renal cell carcinoma histologic grade, staging, and poor prognosis has been reported 37…”

“…CD44 v10‐containing isoforms have been studied regarding tumor progression in breast and renal cell carcinoma 23, 37. Although all CD44 isoforms share HA binding domains, certain CD44 variant isoforms, such as CD44 v10, exhibit significantly reduced affinity for HA binding 27.…”

Prognostic role of CD44 cell adhesion molecule expression in primary and metastatic renal cell carcinoma: a clinicopathologic study of 125 cases

“…Although a contradictory result has been reported concerning the prognostic significance of CD44 immunoexpression in RCC [23], most other studies have shown that high CD44 expression in RCC is associated with poor survival [7,13,17], a significant risk of progression [5,16], and poor tumor differentiation [23]. CD44 expression was shown to be correlated with tumor grade, with higher immunoreactivity observed in higher grade tumors [2,7,23].…”