Table 2.
Main results of pooled HRs in the meta-analysis
| Study number | Sample size | OR/HR (95% CI) | P value | z | Heterogeneity | Publication bias (Eggers test) | |||
|---|---|---|---|---|---|---|---|---|---|
| I2 (%) | Ph | T-value | Pbias | ||||||
| Overall TNM stage (III/IV vs I/II) | 70 | 11,901 | 2.19 (1.84–2.61) | P < 0.001 | 8.83 | 80.74 | P < 0.001 | 2.40 | 0.018 |
| Overall tumor differentiation (poor vs well/moderate) | 59 | 9251 | 1.25 (1.01–1.55) | 0.035 | 2.10 | 82.38 | P < 0.001 | 1.84 | 0.07 |
| Overall lymph node metastasis (Yes vs No) | 76 | 13,172 | 1.76 (1.54–2.02) | 0.00 | 8.23 | 73.57 | P < 0.001 | 2.37 | 0.019 |
| Overall OS | 78 | 13,482 | 1.65 (1.54–1.77) | 0.00 | 14.00 | 56.74 | P < 0.001 | 3.70 | P < 0.001 |
| Overall DFS/RFS | 18 | 1788 | 2.35 (1.90–2.89) | P < 0.001 | 7.96 | 46.93 | 0.015 | 1.63 | 0.12 |
| Overall CSS/ DSS | 8 | 1462 | 1.69 (1.33–2.15) | P < 0.001 | 4.32 | 49.04 | 0.056 | 1.00 | 0.35 |
| CD44s | |||||||||
| TNM stage (III/IV vs I/II) | 9 | 1331 | 2.74 (1.39–5.38) | 0.003 | 2.93 | 83.96 | P < 0.001 | 1.55 | 0.163 |
| Tumor differentiation (poor vs well/moderate) | 9 | 1177 | 2.82 (1.50–5.30) | 0.001 | 3.23 | 75.38 | P < 0.001 | 0.71 | 0.49 |
| Lymph node metastasis (Yes vs No) | 11 | 1638 | 1.64 (1.13–2.38) | 0.009 | 2.62 | 56.83 | 0.010 | 1.65 | 0.13 |
| OS | 11 | 1669 | 1.97 (1.55–2.50) | P < 0.001 | 5.61 | 54.99 | 0.014 | 1.62 | 0.13 |
| DFS/RFS | 5 | 516 | 2.74 (1.80–4.17) | P < 0.001 | 4.69 | 42.23 | 0.14 | – | – |
| CSS/DSS | 2 | 246 | 2.59 (1.32–5.06) | 0.005 | 2.78 | 0.00 | 0.65 | – | – |
| CD44V6 | |||||||||
| TNM stage (III/IV vs I/II) | 3 | 311 | 2.50 (1.22–5.14) | 0.012 | 2.51 | 70.46 | 0.034 | 0.40 | 0.75 |
| Tumor differentiation (poor vs well/moderate) | 5 | 684 | 0.93 (0.35–2.42) | 0.88 | − 0.14 | 86.80 | P < 0.001 | 0.55 | 0.61 |
| Lymph node metastasis (Yes vs No) | 5 | 684 | 2.26 (1.46–3.51) | P < 0.001 | 3.65 | 25.64 | 0.25 | 1.68 | 0.19 |
| OS | 3 | 512 | 1.81 (1.29–2.53) | 0.001 | 3.45 | 0.00 | 0.82 | 2.34 | 0.25 |
| CSS/DSS | 3 | 295 | 3.29 (1.46–7.43) | 0.004 | 2.87 | 61.63 | 0.10 | – | – |
| CD44V9 | |||||||||
| TNM stage (III/IV vs I/II) | 2 | 637 | 5.39 (2.70–10.77) | P < 0.001 | 4.78 | 7.26 | 0.29 | – | – |
| Tumor differentiation (poor vs well/moderate) | 3 | 559 | 0.98 (0.37–2.58) | 0.98 | − 0.025 | 84.72 | 0.001 | 14.65 | 0.043 |
| Lymph node metastasis (Yes vs No) | 3 | 559 | 1.52 (0.91–2.52) | 0.10 | 1.61 | 40.74 | 0.18 | 8.64 | 0.073 |
| OS | 2 | 619 | 1.22 (0.96–1.54) | 0.08 | 1.69 | P < 0.001 | 0.74 | – | – |
| DFS/RFS | 2 | 168 | 8.60 (1.70–43.57) | 0.009 | 2.61 | 77.51 | 0.035 | – | – |
| CSS/DSS | 2 | 246 | 1.67 (0.52–5.35) | 0.38 | 0.86 | 0.00 | 0.48 | – | – |
| CD133 | |||||||||
| TNM stage (III/IV vs I/II) | 11 | 1853 | 2.67 (1.84–3.89) | P < 0.001 | 5.16 | 54.01 | 0.016 | 0.25 | 0.80 |
| Tumor differentiation (poor vs well/moderate) | 10 | 1677 | 0.87 (0.56–1.34) | 0.53 | − 0.62 | 70.18 | P < 0.001 | 2.09 | 0.06 |
| Lymph node metastasis (Yes vs No) | 11 | 1847 | 1.85 (1.22–2.79) | 0.003 | 2.93 | 65.05 | 0.001 | 0.99 | 0.34 |
| OS | 12 | 1939 | 1.74 (1.52–2.01) | P < 0.001 | 7.87 | 0.00 | 0.55 | 1.83 | 0.09 |
| DFS/RFS | 3 | 343 | 2.59 (1.74–3.85) | P < 0.001 | 4.69 | 0.00 | 0.64 | – | – |
| Sox-2 | |||||||||
| TNM stage (III/IV vs I/II) | 5 | 732 | 1.37 (0.65–2.90) | 0.40 | 0.83 | 77.22 | 0.002 | 1.55 | 0.21 |
| Tumor differentiation (poor vs well/moderate) | 2 | 119 | 1.21 (0.57–2.59) | 0.60 | 0.51 | 23.37 | 0.25 | – | – |
| Lymph node metastasis (Yes vs No) | 5 | 732 | 1.96 (1.40–2.73) | P < 0.001 | 3.99 | 0.00 | 0.42 | 0.84 | 0.46 |
| OS | 6 | 804 | 1.73 (1.37–2.18) | P < 0.001 | 4.63 | 0.00 | 0.78 | 0.59 | 0.58 |
| DFS/RFS | 1 | 69 | 1.31 (0.68–2.49) | 0.41 | 0.82 | 0.00 | 1 | – | – |
| Oct-4 | |||||||||
| TNM stage (III/IV vs I/II) | 6 | 1014 | 2.25 (1.09–4.66) | 0.028 | 2.19 | 81.91 | P < 0.001 | 0.79 | 0.47 |
| Tumor differentiation (poor vs well/moderate) | 5 | 724 | 1.97 (0.86–4.50) | 0.10 | 1.60 | 75.47 | 0.003 | 0.53 | 0.62 |
| Lymph node metastasis (Yes vs No) | 6 | 1014 | 2.70 (1.09–6.68) | 0.031 | 2.15 | 88.63 | P < 0.001 | 1.15 | 0.31 |
| OS | 7 | 1086 | 1.87 (1.48–2.35) | 0.00 | 5.37 | 4.88 | 0.38 | 0.21 | 0.83 |
| DFS/RFS | 2 | 114 | 2.18 (1.06–4.48) | 0.023 | 2.13 | 11.13 | 0.28 | – | – |
| ALDH1 | |||||||||
| TNM stage (III/IV vs I/II) | 4 | 760 | 3.66 (1.75–7.64) | 0.001 | 3.45 | 74.19 | 0.009 | 1.31 | 0.31 |
| Tumor differentiation (poor vs well/moderate) | 3 | 539 | 2.73 (0.43–17.19) | 0.28 | 1.07 | 93.25 | P < 0.001 | 4.6 | 0.13 |
| Lymph node metastasis (Yes vs No) | 4 | 760 | 2.50 (0.96–6.45) | 0.058 | 1.89 | 88.08 | P < 0.001 | 0.09 | 0.93 |
| OS | 5 | 851 | 1.65 (1.32–2.05) | P < 0.001 | 4.53 | 0.00 | 0.49 | 2.60 | 0.08 |
| DFS/RFS | 2 | 307 | 1.49 (0.73–3.00) | 0.27 | 1.10 | 56.39 | 0.13 | – | – |
| LGR-5 | |||||||||
| TNM stage (III/IV vs I/II) | 5 | 1392 | 1.31 (0.46–3.74) | 0.60 | 0.51 | 94.11 | P < 0.001 | 0.58 | 0.6 |
| Tumor differentiation (poor vs well/moderate) | 5 | 1423 | 1.04 (0.50–2.13) | 0.91 | 0.10 | 87.79 | P < 0.001 | 0.36 | 0.73 |
| Lymph node metastasis (Yes vs No) | 6 | 1879 | 1.21 (0.70–2.09) | 0.48 | 0.70 | 84.70 | P < 0.001 | 0.01 | 0.98 |
| OS | 5 | 1879 | 1.26 (0.97–1.63) | 0.075 | 1.78 | 60.45 | 0.039 | 1.03 | 0.37 |
| CSS/DSS | 1 | 456 | 1.02 (0.67–1.54) | 0.90 | 0.11 | 0.00 | 1.00 | – | – |
| Bmi-1 | |||||||||
| TNM stage (III/IV vs I/II) | 4 | 792 | 2.85 (1.04–7.81) | 0.041 | 2.04 | 88.46 | P < 0.001 | 1.07 | 0.36 |
| Tumor differentiation (poor vs well/moderate) | 4 | 792 | 1.14 (0.70–1.85) | 0.57 | 0.55 | 51.72 | 0.10 | 0.09 | 0.93 |
| Lymph node metastasis (Yes vs No) | 5 | 1101 | 2.26 (1.19–4.26) | 0.012 | 2.51 | 76.82 | 0.002 | 1.13 | 0.33 |
| OS | 4 | 882 | 1.32 (0.77–2.27) | 0.30 | 1.06 | 84.49 | P < 0.001 | 1.57 | 0.25 |
| CSS/DSS | 1 | 219 | 1.97 (1.35–2.87) | P < 0.001 | 3.52 | 0.00 | 1.00 | – | – |
| Nanog | |||||||||
| TNM stage (III/IV vs I/II) | 3 | 464 | 1.34 (0.78–2.31) | 0.27 | 1.08 | 0.86 | P < 0.001 | 0.49 | 0.70 |
| Tumor differentiation (poor vs well/moderate) | 2 | 174 | 1.89 (0.06–55.82) | 0.71 | 0.37 | 93.05 | P < 0.001 | – | – |
| Lymph node metastasis (Yes vs No) | 3 | 464 | 1.49 (0.73–3.02) | 0.26 | 1.10 | 44.43 | 0.16 | 0.71 | 0.60 |
| OS | 3 | 464 | 1.59 (0.68–3.77) | 0.28 | 1.07 | 80.97 | 0.005 | 0.93 | 0.52 |
| DFS/RFS | 1 | 69 | 2.09 (0.92–4.70) | 0.075 | 1.77 | 0.00 | 1 | – | – |
| CD24 | |||||||||
| TNM stage (III/IV vs I/II) | 5 | 905 | 1.31 (0.87–1.98) | 0.18 | 1.32 | 43.46 | 0.13 | 0.91 | 0.42 |
| Tumor differentiation (poor vs well/moderate) | 2 | 393 | 1.10 (0.18–6.46) | 0.91 | 0.10 | 90.02 | 0.002 | – | – |
| Lymph node metastasis (Yes vs No) | 5 | 905 | 1.40 (1.04–1.89) | 0.026 | 2.23 | 20.17 | 0.28 | 0.46 | 0.67 |
| OS | 5 | 905 | 1.73 (1.25–2.4) | 0.001 | 4.10 | 35.46 | 0.18 | 2.71 | 0.07 |
| Gli-1 | |||||||||
| TNM stage (III/IV vs I/II) | 6 | 614 | 4.00 (1.58–10.13) | 0.003 | 2.93 | 79.50 | P < 0.001 | 1.07 | 0.34 |
| Tumor differentiation (poor vs well/moderate) | 4 | 403 | 1.66 (0.81–3.40) | 0.16 | 1.39 | 57.08 | 0.07 | 0.93 | 0.44 |
| Lymph node metastasis (Yes vs No) | 5 | 493 | 3.04 (1.62–5.71) | 0.001 | 3.47 | 51.59 | 0.08 | 0.60 | 0.59 |
| OS | 8 | 776 | 1.75 (1.34–2.31) | 0.00 | 4.06 | 7.79 | 0.37 | 0.14 | 0.88 |
| DFS/RFS | 1 | 101 | 3.40 (1.30–8.7) | 0.012 | 2.52 | 0.00 | 1 | – | – |
| Shh | |||||||||
| TNM stage (III/IV vs I/II) | 7 | 1096 | 2.19 (0.97–4.94) | 0.056 | 1.90 | 86.32 | P < 0.001 | 3.12 | 0.026 |
| Tumor differentiation (poor vs well/moderate) | 5 | 687 | 1.02 (0.24–4.30) | 0.97 | 0.037 | 90.31 | P < 0.001 | 1.63 | 0.20 |
| Lymph node metastasis (Yes vs No) | 7 | 1096 | 1.14 (0.54–2.39) | 0.73 | 0.34 | 85.02 | P < 0.001 | 0.48 | 0.64 |
| OS | 7 | 1096 | 1.27 (0.78–2.05) | 0.32 | 0.99 | 76.23 | P < 0.001 | 0.72 | 0.49 |
| DFS/RFS | 1 | 101 | 2.75 (1.15–6.54) | 0.02 | 2.28 | 0.00 | 1 | – | – |
Ph: The p-value of heterogeneity; P bias: The p-value of Egger test for assessing publication bias; OS: Overall survival; DFS: Disease-free survival; RFS: Relapse-free survival; CSS: Cancer-specific survival; DSS: Disease-specific survival