Table 1.
Summary of investigated and published biomarkers in the GERD-BE-EAC axis. The categorization is based on four groups according to their potential usage as A = Diagnostic Biomarker indicates the presence of disease, B = Progression Biomarker indicates the risk of developing cancer—progression in BE to EAC, C = Predictive Biomarker predicts response to therapy (CTX, RTX, photodynamic therapy), or D = Prognostic Biomarker indicates overall survival—prognostic in EAC (survival, recurrence).
| Biomarker | Method | Remarks/findings | OR/RR/P value | Refs | |
|---|---|---|---|---|---|
| A = Diagnostic Biomarker | TFF3 | novel nonendoscopic screening modality in a prospective cohort study |
P = 0.02 (for maximal length of BE) P = 0.009 (for circumferential length of BE) |
[48] | |
| TFF3 | IHC, esophageal cytosponge samples for BE combined with IHC for TFF3 | biomarker to screen asymptomatic patients for BE; TFF3 protein was expressed at the luminal surface of BE (not at normal esophageal or gastric mucosa) |
P < 0.0001 | [49] | |
| Chromosomes 7 and 17 (copy number changes) | ICDA & FISH | chromosomal gains in early stages of BE; valuable adjunct to conventional cytology to detect dysplasia or EAC |
IND/LGD: 75% sensitivity, (76% specificity) HGD/EAC: 85% sensitivity, (84% specificity) |
[50] | |
| 8q24 (C-MYC), 17q12 (HER2), and 20q13 (copy number changes) | FISH | chromosomal gains in early stages of BE; represents a valuable adjunct to conventional cytology to detect dysplasia or EAC |
LGD (50% sensitivity) HGD (82% sensitivity) EAC (100% sensitivity) |
[51] | |
| 17q11.2 (ERBB2) | Southern blotting, microarray analysis | amplified copies of the ERBB2 gene in EAC | 10-fold amplification in 3 of 25 (12%) tumors | [52] | |
| Serum proteomic pattern analysis | mass spectrometry | several limitations due to applied technology | identified 10 of 11 normal's; and 42 of 43 EAC's correctly | [53] | |
|
| |||||
| B = Progression Biomarkers | P53 positivity | IHC | limited efficacy as a single progression biomarker | OR 11.7 (95% CI: 1.93–71.4) | [54] |
| P53 positivity | IHC | positive in 4/31 that regressed, 3/12 that persisted, and 3/5 that progressed to HGD or EAC | RR not available | [55] | |
| DNA content abnormalities | flow cytometry | higher relative risk for EAC in patients with tetraploidy (4N) or aneuploidy (>6%) | tetraploidy: RR 7.5 (95% CI: 4–14) (P < 0.001) aneuploidy: RR 5.0 (95% CI: 2.7–9.4) (P < 0.001) |
[56] | |
| 4N fraction cut point of 6% for cancer risk | RR 11.7 ( 95% CI: 6.2–22) | ||||
| aneuploid DNA contents of 2.7N were predictive of higher cancer risk | RR 9.5 (95% CI: 4.9–18) | ||||
| DNA content abnormalities | flow cytometry | presence of both 4N fraction of 6% and aneuploid DNA content of 2.7N is highly predictive for progression | RR 23 (95% CI: 10–50) | [57] | |
| 17p(p53) LOH associated with higher risk of progression to HGD + EAC | HGD: RR 3.6 (P = 0.02) | ||||
| flow cytometry, PCR | EAC: RR 16 (P < 0.001) | [58] | |||
| combined LOH of 17p and 9p and DNA content abnormalities can best predict progression to EAC | RR 38.7 (95% CI: 10.8–138.5) not clinical applicable | ||||
| LOH of 157p and 9p and DNA content abnormalities | LOH of 17p alone | RR 10.6 (95% CI: 5.2–21.3) | |||
| flow cytometry, PCR | LOH of 9p alone | RR 2.6 (95% CI: 1.1–6.0) | |||
| Aneuploidy alone | RR 8.5 (95% CI: 4.3–17.0) | [59] | |||
| Tetraploidy alone | RR 8.8 (95% CI: 4.3–17.7) | ||||
| mutations of p16 and p53 loci (clonal diversity measurements) | flow cytometry, PCR | significant predictors for EAC progression, not clinical applicable | P = 0.001 | [60] | |
| EGFR | IHC | overexpression in HGD/EAC | 35% of HGD/80% of EAC specimens | [61] | |
| MCM2 | IHC | correlation between degree of dysplasia and level of ectopic luminal surface MCM2 expression | MCM2-positive staining in 42% (19/45) of BE samples |
[62] | |
| Cyclin A | IHC | surface expression of cyclin A in BE samples correlates with the degree of dysplasia | OR 7.5 (95% CI: 1.8–30.7) (P = 0.016) | [63] | |
| Cyclin D1 | IHC | association with increased risk of EAC | OR 6.85 (95% CI: 1.57–29.91) | [64] | |
| hypermethylation of p16 (CDKI2A) | association with increased risk of progression to HGD/EAC | OR 1.74 (95% CI: 1.33–2.2) | |||
| hypermethylation of RUNX3 | association with increased risk of progression to HGD/EAC | OR 1.80 (95% CI: 1.08–2.81) | |||
| hypermethylation of HPP1 | RT-PCR | association with increased risk of progression to HGD/EAC | OR 1.77 (95% CI: 1.06–2.81) | [41] | |
| hypermethylation of p16 and APC | PCR | predictor of progression to HGD/EAC | OR 14.97 (95% CI: 1.73–inf.) | [65] | |
| 8 gene methylation panel | RT-PCR | age dependent; predicts 60.7% of progression to HGD/EAC within 2 yrs | RR not available (90% specificity) | [66] | |
| Gene expression profile | microarray analysis | 64 genes up regulated 110 genes down regulated in EAC |
P = 0.05 | [67] | |
| Cathepsin D, AKR1B10, and AKR1C2 mRNA levels | Western blotting, qRT-PCR | dysregulation predicts progression to HGD/EAC | AKR1C2: ↑ levels in BE (P < 0.05) but ↓ levels in EA (P < 0.05) |
[68] | |
| ICDA | aneuploidy predicts progression to EAC | 60% with LGD; 73% with HGD, and 100% with EAC (total number of samples = 56) | [69] | ||
| DNA abnormalities | ACIS | frequency and severity of aneuploidy predicts progression to EAC | unstable aneuploidy in 95% with EAC | [70] | |
| DICM | relationship between DICM status and progression to HGD/EAC | P < 0.0001 | [71] | ||
| SNP-based genotyping in BE/EAC specimens | flow cytometry, 33K SNP array | copy gains, losses, and LOH increased in frequency and size between early and late stage of disease | P < 0.001 (BE) | [72] | |
|
| |||||
| C = Predictive Biomarkers | p16 allelic loss | FISH | decreased response to photodynamic therapy | OR 0.32 (95% CI: 0.10–0.96) | [73] |
| DNA ploidy abnormalities | ICDA | DNA ploidy as a covariate value for recurrence | HR 6.3 (1.7–23.4) (P < 0.0015) | [74] | |
| HSP27 | IHC | association between low HSP27 expression and no response to neoadjuvante chemotherapy | P = 0.049 and P = 0.032 | [75] | |
| Ephrin B3 receptor | microarray | response prediction in EAC in patients with Ephrin B3 receptor positive versus Ephrin B3 receptor negative | Response rate <50%: 3 (15.8) versus 16 (84.2) (P < 0.001) | [76] | |
| Genetic polymorphisms | qRT-PCR | association between individual single nucleotide polymorphisms and clinical outcomes |
comprehensive panel of genetic polymorphisms on clinical outcomes in 210 esophageal cancer patients | [77] | |
| P21 | IHC | alteration in expression correlated with better CTX-response | P = 0.011 | [78] | |
| P53 | IHC | alteration in expression correlated with better CTX-response | P = 0.011 | [79] | |
| ERCC1 | IHC | ERCC1-positivity predicts CTX-resistance and poor outcome | P < 0.001 | [80] | |
|
| |||||
| D = Prognostic Biomarkers | DCK PAPSS2 SIRT2 TRIM44 |
RT-PCR, IHC |
prognostic 4-gene signature in EAC predicts 5-year survival | 0/4 genes dysregulated: 58% (95% CI: 36%–80%) 1-2/4 genes dysregulated: 26% (95% CI: 20%–32%) 3-4/4 genes dysregulated: 14% (95% CI: 4%–24%) (P = 0.001) |
[81] |
|
p16 loss C-MYC gain |
FISH | association between therapy response status and FISH positivity | P = 0.04 | [82] | |
| ASS expression | microarrays | low expression correlates with lymph node metastasis | P = 0.048 | [83] | |
| microRNA expression profiles | miRNA microarray, qRT-PCR | association with prognosis (e.g. low levels of mir-375 in EAC → worse prognosis) | HR = 0.31 (95% CI: 0.15–0.67) (P < 0.005) | [84] | |
| Genomic alterations | MLPA | reverse association between survival and DNA copy number alterations (>12 aberrations → low mean survival) | P = 0.003 | [85] | |
| Cyclin D1 | FISH, IHC | 2 of 3 genotypes confers to ↓ survival | P = 0.0003 | [86] | |
| IHC | expression = ↓ survival | P = 0.07 | [87] | ||
| EGFR | IHC | ↓ expression = ↓ survival | P = 0.034 | [88] | |
| Ki-67 | IHC | low levels of staining (<10%) = ↓ survival |
P = 0.02 | [89] | |
| Her2/neu | FISH | amplification = ↓ survival | P = 0.03 | [90, 91] | |
| IHC | low levels = ↓ survival | P = 0.03 | [92] | ||
| TGF-α | IHC, ISH | high levels = tumor progression and lymph node metastasis | P = 0.025 and P < 0.05 | [93] | |
| qRT-PCR | overexpression = ↓ survival | P = 0.0255 | [94] | ||
| TGF-β1 | ELISA | high plasma levels = ↓ survival | P = 0.0317 | [95] | |
| APC | RT-PCR | high plasma levels of methylation = ↓ survival |
P = 0.016 | [96] | |
| Bcl-2 | IHC | expression = ↓ survival | P = 0.03 | [97] | |
| IHC, RT-PCR | ↑ expression = ↓ survival, ↑ TN-stage, and recurrence |
P < 0.001, P = 0.008/0.049, and P = 0.01 |
[98] | ||
| IHC | strong staining = ↓ survival | P = 0.03 | [99] | ||
| COX-2 | IHC | strong staining = ↓ survival, distant metastasis, and recurrence | P = 0.002, P = 0.02, and P = 0.05 | [100] | |
| NF-κB | IHC | activated NF-κB = ↓ survival, and ↓ disease free survival |
P = 0.015 and P = 0.010 | [101] | |
| Telomerase | Southern blot analysis, RT-PCR | higher telomere-length ratio = ↓ survival |
RR of death: 3.4 (CI: 1.3–8.9) (P < 0.02) |
[102] | |
| expression = ↓ survival, | P < 0.01 | ||||
| CD105 | angiolymphatic invasion | P < 0.05 | |||
| ↑ lymph node metastasis | P < 0.01 | ||||
| ↑ T-stage | P < 0.001 | ||||
| IHC | ↑ distant metastasis | P < 0.01 | [103] | ||
| ↑ expression = ↓ survival, | P < 0.01 | ||||
| VEGF | angiolymphatic invasion | P < 0.05 | |||
| ↑ lymph node metastasis | P < 0.01 | ||||
| ↑ T-stage | P < 0.01 | ||||
| ↑ distant metastasis | P < 0.01 | ||||
| Cadherin | IHC | ↓ level = ↓ survival | P = 0.05 | [89] | |
| uPA | ELISA | ↑ uPA = ↓ survival | P = 0.0002 | [104] | |
| TIMP | IHC, RT-PCR | ↓ expression = ↓ survival, and ↑ disease stage | P = 0.007 and P = 0.046 | [105] | |
| Promoter hypermethylation of multiple genes | IHC, methylation specific PCR | if >50% of gene profile methylated = ↓ survival, and earlier recurrence |
P = 0.05 and P = 0.04 | [106] | |
| MGMT hypermethylation | IHC, methylation specific PCR | correlation with higher tumor differentiation | P = 0.0079 | [107] | |
ACIS: automated cellular imaging system; ASS: argininosuccinate synthase; APC: adenomatous polyposis coli; BE: barrett's esophagus; COX: cyclooxygenase; DCK: deoxycytidine kinase; DICM: digital image cytometry; EAC: esophageal adenocarcinoma; EGFR: epidermal growth factor receptor; ELISA: enzyme-linked immunosorbent assay; FISH: fluorescence in-situ-hybridization; ICDA: image cytometric DNA analysis; HSP27: Heat-shock protein 27; IHC: immunohistochemistry; LOH: loss of heterozygosity; PAPSS2: 3′-phosphoadenosine 5′-phosphosulfate synthase 2; PCR: polymerase chain reaction; qRT: quantitative reverse transcriptase; MLPA: multiplex ligation dependent probe amplification; NF-κB: nuclear factor kappa B; SIRT2: Sirtuin 2; SNP: single nucleotide polymorphism; TFF3: Trefoil factor 3; TGF: transforming growth factor; TIMP: tissue inhibitors of metalloproteinases; TRIM44: Tripartite motif-containing 44; uPA: urokinase-type plasminogen activator; VEGF: vascular endothelial growth factor.