Table 1
Characteristics of small-cell lung cancer (SCLC) patients and healthy volunteers
| Characteristic | SCLC patients (N= 50) | Healthy volunteers (N= 34) |
|---|---|---|
| Age in years: median (range) | 65 (46-88) | 62 (47-78) |
| Gender, N (%) | ||
| Male | 34 (68) | 24 (71) |
| Female | 16 (32) | 10 (29) |
| PSaN (%) | ||
| 0–1 | 38(76) | |
| ≥ 2 | 12 (24) | |
| Number of distant metastatic sites, N (%) | ||
| < 3 | 34 (68) | |
| ≥ 3 | 16 (32) | |
| Type of first-line chemotherapy, N (%) | ||
| PE | 42 (84) | |
| CEV | 8 (16) |
PE = platinum (cisplatin or carboplatin)-etoposide

SOX2, NANOG and OCT4 mRNA expression levels in whole blood of healthy volunteers and small-cell lung cancer (SCLC) patients.
N: number of SCLC patients/healthy volunteers; p: p-value
Table 2
Association between SOX2, NANOG and OCT4 mRNA expression and patients` characteristics
| Characteristic | SOX2highb | SOX2lowb | p-value | NANOGhighb | NANOGlowb | p-value | OCT4highb | OCT4lowb | p-value |
|---|---|---|---|---|---|---|---|---|---|
| Age in years: median (range) | 63 (46–78) | 66 (47–88) | 0.301c | 65 (47–79) | 65 (46–88) | 0.648c | 64 (47–77) | 66 (46–88) | 0.466c |
| Gender, N (%) | 0.756d | 0.762d | |||||||
| Male | 2 (35) | 22 (65) | 18 (53) | 16 (47) | 16 (47) | 18 (53) | 0.762d | ||
| Female | 7 (44) | 9 (56) | 7 (44) | 9 (56) | 9 (56) | 7 (44) | |||
| PSa, N (%) | 0.332d | 0.742d | 1.000d | ||||||
| 0–1 | 16 (42) | 22 (58) | 20 (53) | 18 (47) | 19 (50) | 19 (50) | |||
| ≥ 2 | 3 (25) | 9 (75) | 5 (42) | 7 (58) | 6 (50) | 6 (50) | |||
| Number of distant metastatic sites, N (%) | 0.027d | 0.762d | 1.000d | ||||||
| < 3 | 9 (26) | 25 (74) | 18 (53) | 16 (47) | 17 (50) | 17 (50) | |||
| ≥ 3 | 10 (62) | 6 (38) | 7 (44) | 9 (56) | 8 (50) | 8 (50 |
N = number of patients
b bmedian mRNA expression levels for each of the three markers analysed were used to stratify patients as either SOX2/NANOG/OCT4 low or high
b bmedian mRNA expression levels for each of the three markers analysed were used to stratify patients as either SOX2/NANOG/OCT4 low or high
b bmedian mRNA expression levels for each of the three markers analysed were used to stratify patients as either SOX2/NANOG/OCT4 low or high
b bmedian mRNA expression levels for each of the three markers analysed were used to stratify patients as either SOX2/NANOG/OCT4 low or high
b bmedian mRNA expression levels for each of the three markers analysed were used to stratify patients as either SOX2/NANOG/OCT4 low or high
Table 3
Progression-free survival (PFS) after first-line chemotherapy and overall survival (OS) according to SOX2, NANOG and OCT4 mRNA expression
| mRNA expression | Median PFS (months) | p-value HR (95% CI) | Median OS (months) | p-value HR (95% CI) | ||
|---|---|---|---|---|---|---|
| UV | MV | UV | MV | |||
| All patients (N = 50) | 6.2 | 8.4 | ||||
| SOX2 low | 7.4 | 0.046 | 0.377 | 9.9 | 0.017 | 0.002 |
| SOX2 high | 5.6 | 1.988 (1.011-3.922) | 1.054 (0.938-1.183) | 7.5 | 2.370 (1.164-4.831) | 3.205 (1.536-6.711) |
| NANOG low | 5.7 | 0.221 | 0.299 | 7.4 | 0.347 | 0.376 |
| NANOG high | 6.5 | 0.693 (0.384-1.247) | 0.864 (0.656-1.139) | 8.7 | 0.750 (0.412-1.366) | 0.884 (0.674-1.161) |
| OCT4 low | 5.6 | 0.156 | 0.227 | 7.8 | 0.251 | 0.416 |
| OCT4 high | 7.3 | 0.652 (0.362-1.178) | 0.780 (0.521-1.167) | 9.9 | 0.810 (0.446-1.471) | 0.891 (0.673-1.178) |
95% CI = 95% confidence interval; HR = hazard ratio; MV = multivariate analysis adjusted for age, gender, N = number of patients; PS and the number of distant metastatic sites; relative expression values for each of the three markes analysed were used in MV; UV = univariate analysis; Log-rank test was used to analyse different categories dichotomised according to the median mRNA expression levels for each of the three markers analysed

Progression-free survival (PFS) after first-line chemotherapy according to SOX2(A), NANOG(B) and OCT4(C) mRNA expression in small-cell lung cancer patients. p: p-value

Overall survival (OS) according to SOX2(A), NANOG(B) and OCT4(C)mRNA expression in small-cell lung cancer patients. p: p-value.