Table 1.
Description of CXCR4 assessment methodology among selected studies.
| First Author |
Methods | Fresh Tissue Evaluation | Detection Correlated with TTO | Differential Nuclear, Cytoplasmic, Membrane IHC Staining | IHC Distribution Correlated with Prognosis | Scores | No. of Positive Cells for Expression Evaluation | Inclusion of “Staining Intensity” |
|---|---|---|---|---|---|---|---|---|
| Kim J. | IHC, RT-PCR | Yes | RT-PCR | NA | NA | Low vs.High | mRNA median CXCR4 expression | No |
| Ottaiano A. | IHC | No | IHC | Yes | Overall expression | Neg/Low vs. High | ≤50% vs.>50% | No |
| Yoshitake N. | IHC, Western Blot | No | IHC | Yes | Overall expression | Neg vs. Pos | No CXCR4 immunoreactivity vs others | No |
| Speetjens F.M. | RT-PCR | No | RT-PCR | NA | NA | Low vs. High | mRNA median CXCR4 expression | No |
| Speetjens F.M. | IHC | No | IHC | Yes | Nuclear expression | Weak vs. Strong | Examples are included in the work | Yes |
| Ingold B. | IHC | No | IHC | No | Overall expression | 0, 1+, 2+, 3+ | NA | Yes Absent, faint cytoplasmic, moderate cytoplasmic and slight membranous, strong cytoplasmic and strong membranous |
| Wang S.C. | IHC, RT-PCR | No | IHC | Yes | Nuclear expression | 0, 1+, 2+, 3+ | 0; <30%; 30–50%; >50% |
Yes Weak, medium, strong, very strong |
| Yopp A.C. | IHC | No | IHC | Yes | Overall expression | Neg vs. Pos | ≤10% vs.>10% | No |
| Sakai N. | IHC, fluorescence microscopy | No | IHC | Cyto | Cytoplasm | Low vs. High | NA | Yes Relative to the staining intensity of hepatocytes |
| Sakai N. | IHC, fluorescence microscopy | No | IHC | Nucleus | Nuclear | Neg vs. Pos | NA | Yes Relative to the staining intensity of hepatocytes |
| Du C. | IHC | No | IHC | Not Specified | Overall expression | 0, 1+, 2+: Low3+: High | <1%; 1–50% (1+ and 2+); >50% |
Yes Negative, weak, strong |
| Gao Y. | IHC, RT-PCR | No | IHC | No | Overall expression | Sporadic, focal, diffuse | <10%, ≥11<50%, ≥50% | Yes Negative, weak, moderate, strong |
| Stanisavljevic L. (cohort 1) |
IHC, ISH | No | IHC | Yes | Nuclear expression | Low vs. High | 0–20%, >20% | No |
| Stanisavljevic L. (cohort 2) |
IHC | No | IHC | Yes | Nuclear expression | Low vs. High | 0–20%, >20% | No |
| D′Alterio C. | IHC, RT-PCR | No | IHC | Yes | Overall expression | Negative/Low vs. High | 0–50%, >50% | No |
| Wu W. | IHC, RT-PCR | No | RT-PCR | NA | NA | Low vs. High | mRNA median CXCR4 expression | No |
| Weixler B. | IHC | No | IHC | No | Overall expression | Histoscores (a continuous variable) |
(% of positive cells)x (staining intensity) | Yes Negative, 0; weak, 1; moderate, 2; strong, 3 |
| Xu C. | IHC, RT-PCR | No | IHC | No | Membrane | 0, 1, 2, 3, 4 | 0%, 1–25%, 26–50%, 51–75%, >75% | Yes No staining, weak, moderate, strong |
| Ottaiano A. | IHC, RT-PCR | No | IHC | Yes | Overall expression | Neg/Low vs. High | ≥0≤50%, >50% | No |
IHC: Immunohistochemistry; ISH: In situ hybridization; mRNA: messenger ribonucleic acid; NA: not applicable; Neg: negative; Pos: positive; RT-PCR: reverse transcriptase-polymerase chain reaction; TTO: time to outcome.