Table 1. Characteristics of studies included in this meta-analysis.
| First author | Year | Location | material | Patient and control | Method | RARβ2 (M/U)b | Pa(M/U)b | GS(M/U)b | |||
| case | control | Low-gradec | High-grade | Low-GSd | High-GS | ||||||
| Dumache R | 2012 | Romania | blood | 91/94 | QMSP | 89/91 | 10/94 | - | - | - | - |
| Bastian PJ | 2007 | Germany | tissues | 78/30 | MSP | 56/78 | 1/38 | 32/47 | 24/31 | 30/48 | 26/30 |
| Rouprêt M | 2007 | UK | urine | 95/32 | QMSP | 59/95 | 1/32 | - | - | 28/55 | 31/40 |
| Hanson JA | 2006 | USA | tissues | 5/5 | QMSP | 4/5 | 0/5 | - | - | 3/18 | 8/20 |
| Henrique R | 2006 | USA | tissues | 30/30 | QMSP | 26/30 | 6/30 | 18/20 | 2/10 | 14/15 | 13/15 |
| Hoque MO | 2005 | USA | urine | 52/91 | QMSP | 18/52 | 8/91 | 7/24 | 11/28 | 11/24 | 7/28 |
| Jerónimo C | 2004 | USA | tissue | 118/30 | QMSP | 115/118 | 7/30 | - | - | - | - |
| Karen Woodson | 2004 | USA | tissue | 24/11 | MSP | 18/24 | 0/11 | - | - | 11/35 | 7/9 |
| Jingmei Zhang | 2004 | USA | tissue | 50/2 | MSP | 42/50 | 0/2 | - | - | 14/18 | 28/32 |
| Yamanaka M | 2003 | Japan | tissue | 109/36 | MSP | 85/109 | 0/36 | 29/39 | 56/70 | 33/47 | 52/62 |
| Maruyama R | 2002 | USA | tissue | 101/25 | MSP | 54/101 | 1/25 | 12/26 | 22/34 | 11/36 | 44/65 |
| Nakayama T | 2001 | Japan | tissue | 24/10 | MSP | 20/24 | 0/10 | - | - | - | - |
MSP, methylati on specific PCR; QMSP, quantitative methylation specific PCR. aP pathologic stage; bRARβ2 methylated/RARβ2 unmethylated; cpathologic stage≤ T2 was defined as low-stage and pathologic stage≥ T3 was defined as high-stage; dGleason score≤6 was defined as low-GSand Gleason score≥7 was defined as high-GS.