Table 1. Characteristics of studies for association between OPN and colorectal cancers.
| Study/Year (Reference) | Tumor site | Sample size | Sample source | Tumor grade (I–II/III–IV) | OPN Detection method | cut-off level of ‘high’ OPN expression | No. of patients with ‘high’ OPN | Follow-up duration (months) | Survival rate (%) |
Study quality (Points) | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2-year |
3-year |
5-year |
|||||||||||||
| Low OPN | High OPN | Low OPN | High OPN | Low OPN | High OPN | ||||||||||
| Rohde F 2007 | colon | 120 | Tissue | NR | RT-PCR | ≥9-fold | 39 | 44–131 | 88.9 | 66.7 | 82.7 | 53.8 | 77.8 | 51.3 | 8/9 |
| Chen SH 2007 | colorectal | 60 | Tissue | 20/40 | IHC | >10% | 40 | NR | NR | NR | NR | NR | NR | NR | 6/9 |
| Wang XF 2008 | colon | 60 | Tissue | 17/43 | IHC | IRS ≥ 4 | 43 | NR | NR | NR | NR | NR | NR | NR | 6/9 |
| Chen Y 2009 | colorectal | 76 | Serum | NR | Elisa | >157.9 ng/ml | 38 | NR | NR | NR | NR | NR | NR | NR | 6/9 |
| Likui W 2010 | colorectal | 84 | Tissue | 75/9 | RT-PCR | >value of 0.276 | 42 | 60 | 92.9 | 71.4 | 83.3 | 52.4 | 71.4 | 45.2 | 7/9 |
| Wild N 2010 | colorectal | 265 | Serum | NR | Elisa | >specificity of 95% | 80 | NR | NR | NR | NR | NR | NR | NR | 6/9 |
| Lin AY 2011 | colorectal | 154 | Tissue | NR | IHC | IRS ≥ 2 | 90 | 7–184 | 60.6 | 53.3 | 52.5 | 48.9 | 47.5 | 37.8 | 8/9 |
| Zhao M 2011 | colorectal | 30 | Tissue | NR | IHC | IRS ≥ 4 | 23 | NR | NR | NR | NR | NR | NR | NR | 6/9 |
| Jing LI 2012 | colorectal | 77 | Tissue | 57/20 | IHC | >10% | 38 | NR | NR | NR | NR | NR | NR | NR | 6/9 |
| Sun L 2012 | colorectal | 213 | Tissue | 186/25 | IHC | IRS ≥ 2 | 76 | NR | NR | NR | NR | NR | NR | NR | 6/9 |
| Yang LJ 2012 | colorectal | 60 | Tissue | 17/43 | IHC | IRS ≥ 1 | 43 | NR | NR | NR | NR | NR | NR | NR | 6/9 |
| Uhlmann ME 2012 | colorectal | 118 | Tissue | NR | RT-PCR | >75% quantile | 26 | 133 | 92.2 | 76.9 | 89.6 | 73.1 | 74.0 | 69.2 | 8/9 |
| Rao G 2013 | colorectal | 190 | Tissue | 138/52 | IHC | Moderate staining | 124 | 60 | 66.7 | 40.3 | 54.5 | 27.4 | 54.5 | 25.8 | 8/9 |
| Viana Lde S 2013 | colorectal | 114 | Tissue | NR | IHC | IRS > 4 | 103 | NR | NR | NR | NR | NR | NR | NR | 6/9 |
| Wang CJ 2014 | colorectal | 76 | Tissue | 34/42 | IHC | IRS > 3 | 39 | NR | NR | NR | NR | NR | NR | NR | 6/9 |
RT-PCR, reverse transcription-polymerase chain reaction; IHC, immunohistochemistry; Elisa, enzyme-linked immunosorbent assay; IRS: immunoreactive score, NR: not reported; OPN: osteopontin.