Cytosol concentrations of CD44 isoforms in breast cancer tissue

Prognostic value of CD44v6 expression in breast cancer: a meta-analysis

Purpose

The prognostic value and clinical significance of CD44 variant isoform v6 (CD44v6) in breast cancer remains controversial. Our study aimed to generalize the correlation between CD44v6 expression and clinicopathological features and prognosis in breast cancer by using a meta-analysis.

Methods

We performed a comprehensive search of relevant literature from PubMed, Cochrane Database, and EMBASE database that were published before January 2018. The pooled ORs and HRs with 95% CIs were used to estimate the effects.

Results

Thirteen articles comprising 1,458 patients were included for analysis. The results revealed that CD44v6 expression was associated with histological grade (overall: OR=1.56, 95% CI [1.06, 2.29], P=0.023; Asian: OR=1.78, 95% CI [1.12, 2.85], P=0.016) and lymph node metastasis (overall: OR=1.96, 95% CI [1.01, 3.78], P=0.046; Asian: OR=2.11, 95% CI [1.00, 4.44], P=0.049). CD44v6 expression was significantly associated with poor prognosis in patients with breast cancer (overall survival: overall: HR=1.55, 95% CI [1.09, 2.22], P=0.015; Asian: HR=2.22, 95% CI [1.34, 3.68], P=0.002).

Conclusion

Our meta-analysis demonstrates that CD44v6 is significantly associated with poor prognosis, histological grade, and lymph node metastasis in breast cancer patients, especially among Asian patients.

Histological Grade in Breast Cancer: Association with Clinical and Biological Features in a Series of 229 Patients

In order to study the association of histological grade (HG) with specific clinical and biological parameters which may influence the clinical behavior of infiltrating ductal carcinomas of the breast (IDC), we analyzed in 229 tissue samples the cytosolic concentrations of estrogen receptor (ER), progesterone receptor (PR), pS2, cathepsin D, hyaluronic acid (HA) and tissue-type plasminogen activator (t-PA), as well as those of the erbB2 oncoprotein, epidermal growth factor receptor (EGFR), HA, CD44v5 and CD44v6 in the cell membrane fraction. Likewise, we considered size, ploidy, S-phase fraction and axillary node involvement as variables of the study. The transition from HG1 to HG2 and from HG2 to HG3 was accompanied by a number of common features: global increase in size, greater number of tumors >2.0 cm, decrease in membrane hyaluronic acid concentrations, increased cell proliferation (S-phase >7%) and greater aneuploidy. Other events observed during the transition from HG2 to HG3 were a decrease in ER, PR, t-PA and cytosolic hyaluronic acid. These results led us to consider that HG is associated with certain clinical-biological changes that may help explain its value as a prognostic factor in breast carcinomas.

The prognostic value of adhesion molecule CD44v6 in women with primary breast carcinoma: a clinicopathologic study

AIMS

CD44 functions as an adhesion molecule. Within the family of CD44 isoforms, the spliced variant 6 has been causally associated with the development of metastases and poor prognosis in animal models and several human cancers. The aim of this study was to investigate the prognostic value of CD44v6 in women with primary breast carcinoma.

MATERIALS AND METHODS

The women with primary breast carcinoma in this study were followed up clinically for a period of 5 years. Clinicopathologic features, including tumour size, axillary nodal status, histological grade and pTNM stage, were determined for a cohort of 78 women presenting with primary breast carcinoma. Standard immunohistochemistry was used to explore CD44v6 expression. The data obtained were analysed by univariate and multivariate analyses.

RESULTS

Forty-three out of 78 (55%) women with breast carcinoma were CD44v6-positive (i.e. over 5% of tumour cells exhibited positive staining). Significant sequential increase of CD44v6 expression was observed in women with metastases of axillary nodes, tumour size more than 2 cm, advanced pTNM stage and survival period less than 5 years. Univariate analysis showed that axillary nodal status, primary tumour size, histological grade, and pTNM stage were associated with 5-year survival, and CD44v6 expression was associated with primary tumour size, axillary nodal status, pTNM stage and 5-year survival. In multivariate analysis, using the Cox-regression model, CD44v6 expression was not an independent prognostic factor.

CONCLUSIONS

CD44v6 expression was correlated with tumour size, metastases of axillary nodes, pTNM stage, and 5-year survival; however, multivariate analysis revealed that CD44v6 expression failed to be an independent predictor of patient prognosis.

Expression of CD44v6 gene in normal human peripheral blood

AIM: To investigate if CD44v6 could be used as a molecular marker of cancer progression and metastasis through the detection of CD44v6 gene expression in normal human peripheral blood.

METHODS: RNA was extracted from the peripheral blood mononuclear cells of 50 healthy donors, the expression of CD44v6 was investigated using reverse transcriptase-polymerase chain reaction (RT-PCR).

RESULTS: CD44v6 mRNA was detected in 58% of healthy volunteers under the proper controls.

CONCLUSION: Our results suggest that the measurement of CD44v6 expression in peripheral blood by RT-PCR is not suitable for detection of circulating tumor cells.

The prognostic significance of CD44s and CD44v6 expression in stage two breast carcinoma: an immunohistochemical study

AIMS

Expression of the v6 variant isoform of CD44 has been causally associated with the development of metastases. This study, using immunohistochemical techniques, examined the prognostic significance of CD44s and CD44v6 expression.

METHODS

A cohort of 109 women presenting with stage 2 breast cancer, with a minimum follow-up of 5 years, were assessed.

RESULTS

Eighty percent of patients demonstrated CD44v6 expression on immunohistochemical studies. CD44v6 expression in tissue sections was found to be independent of age, tumour size, grade, and lymph-node status. No significant association was demonstrated between CD44v6 expression and either disease-free or overall survival. Similar findings were observed for CD44s.

CONCLUSIONS

CD44s and CD44v6 do not appear to be useful as prognostic indicators in early breast cancer. The increased expression of variant CD44 isoforms seen in breast neoplasia may merely be a marker for loss of control of alternative splicing within tumour tissue.

Prognostic value of CD44 variant expression in primary breast cancer

CD44 is a family of cell surface transmembrane glycoproteins members which differ in the extracellular part by sequences derived by alternative splicing of 10 variant exons (v1-v10). CD44 proteins containing such variant sequences have been implicated in tumor metastasis formation. Here, we have evaluated the expression of CD44 variants by immuno-histochemistry in primary breast cancer samples of 237 node-negative and 230 node-positive patients. For the analysis of samples derived from node-negative patients, the exon-specific antibodies used were DIII, vff7 and vff18 (v6), vff17 (v7/v8), fw11.24 (v9) and vff16 (v10). With the different antibodies which recognize v6 epitopes, the majority of tumors were positively stained (> or = 65% of the tumors) with varying intensities. Thirty-nine percent of the tumors were positively stained with the antibody vff16, and approximately half of the tumors with the antibodies vff17 and fw11.24. The expression of CD44 v6 epitopes in tumors from node-negative patients was associated with a favorable prognosis, both upon univariate and multivariate analysis. The expression of CD44 v7/8, v9 or v10 epitopes was not significantly related with relapse-free survival. Samples from node-positive patients were only examined with the antibodies vff7, vff17 and vff18. The staining with none of these antibodies was correlated with the length of relapse-free survival of the patients. Our data suggest that, generally, the usefulness of knowledge of CD44 variant expression is of limited value for assessing the risk of relapse in patients with primary breast cancer. However, the expression of exon v6 of CD44 may be a marker to identify patients with a relatively favorable prognosis in node-negative patients.