Background:
CD44 is widely used as a putative cancer stem cells (CSCs) marker for colorectal cancer (CRC). However, the prognostic role of CD44 in CRC remains controversial.
Methods:
We performed a systematic review and meta-analysis to evaluate the association of various CD44 isoforms and overall survival (OS) and clinicopathological features of CRC patients.
Results:
A total of 48 studies were included in the meta-analysis. Total CD44 isoforms overexpression was significantly correlated with worse OS of patients with CRC (HR = 1.32, 95% CI = 1.08–1.61,
P
= 0.007). In a stratified analysis, a higher level of either CD44v6 or CD44v2 had an unfavorable impact on OS (HR
CD44v6
= 1.50, 95% CI = 1.10–2.14,
P
= 0.010; HR
CD44v2
= 2.93, 95% CI = 1.49–5.77,
P
= 0.002). Additionally, CD44 was shown to be associated with some clinicopathological features, such as lymph node metastasis (OR
CD44
= 1.56, 95% CI = 1.01–2.41,
P
= 0.044; OR
CD44v6
= 1.97, 95% CI = 1.19–3.26,
P
= 0.008; OR
Total CD44 isoforms
= 1.57, 95% CI = 1.15–2.14,
P
= 0.004), distant metastasis (OR
CD44
= 2.90, 95% CI = 1.08–7.83,
P
= 0.035; OR
Total CD44 isoforms
= 1.89, 95% CI = 1.02–3.53,
P
= 0.044). Moreover, a high level of CD44 showed a possible correlation with poor differentiation (OR
Total CD44 isoforms
= 1.44, 95% CI = 1.00–2.08,
P
= 0.051), elevated level of CD44v6 tend to be correlated with tumor size (OR = 1.71, 95% CI = 0.99–2.96,
P
= 0.056).
Conclusions:
This meta-analysis demonstrated that CD44 overexpression might be an unfavorable prognostic factor for CRC patients and could be used to predict poor differentiation, lymph node metastasis and distant metastasis.