IGFBP-5 Overexpression in Urothelial Carcinomas
IGFBP-5 Overexpression in Urothelial Carcinomas
From the transcriptomic profile of 33 high-staged and metastatic cases and 16 low-staged and non-metastatic ones of UBUC, 26 probes covering 21 transcripts associated with regulation of cell growth (GO:0001558) were found (figure 1). The log2 ratios of one transcript met the selection criteria of >1.5 increase (p<0.0001), that is, IGFBP5, with log2 ratio of 1.7363 to 3.3334-fold upregulation (Table 1). Of note, the expression level of IGFBP5 transcript significantly predicted DSS (figure 2, p=0.0120). Detailed information is provided in the online supplementary data.
(Enlarge Image)
Figure 1.
The transcriptome of urinary bladder urothelial carcinomas reconstructed from GSE31684 with focusing on those involving regulation of cell growth (GO: 0001558). The expression levels of 26 probes targeting 21 genes were identified to be significantly different (p<0.01, Log2 ratio >+/0.1) by comparing 33 high-staged (pT2-T4) and metastasising tumour and 16 low-staged (pT0-T1) and non-metastasising lesions.
(Enlarge Image)
Figure 2.
The clinicopathological findings of the UTUC and UBUC cases are listed in Table 2. Detailed information is provided in the online supplementary data.
IGFBP-5 shows variable cytoplasmic expression in the UC of both locations with H-scores in the range of 155 to 485 (median 340) for UTUC and 150 to 490 (median 345) for UBUC. After dichotomising the tumour into low and high IGFBP-5 expression (H-score less than median and no less than median, respectively), as demonstrated in Table 2, increased IGFBP-5 expression showed significant association with increment of pT status (figure 3), lymph node metastasis, a high histological grade, vascular invasion, perineural invasion and frequent mitosis in UC for either location. Detailed information is provided in the online supplementary data.
(Enlarge Image)
Figure 3.
Representative H&E sections of low-stage urothelial carcinoma (UC) (A) demonstrated low cytoplasmic IGFBP-5 expression (C), whereas the high-stage, infiltrating UC (B) shows bright IGFBP-5 expression (D).
The univariate and multivariate analyses of the associations of the clinical outcomes with various clinicopathological in UTUC and UBUC cases are demonstrated in Table 3 and Table 4 respectively. Detailed information is provided in the online supplementary data.
Univariate and multivariate analyses (Table 3 and Table 4 and figure 4) showed that high IGFBP-5 cytoplasmic expression was significantly associated with worse DSS and MeFS in patients with UTUC or UBUC. Detailed information is provided in the online supplementary data.
(Enlarge Image)
Figure 4.
Kaplan-Meier plots show that IGFBP-5 overexpression conferred significant prognostic impacts in disease-specific survival and metastasis-free survival of patients with upper urinary tract urothelial carcinoma (A and B, respectively) and urinary bladder urothelial carcinoma (C and D, respectively).
According to the western blot analysis, IGFBP-5 protein is detected in urothelial cancer cells including RT4, TSGH8301, J82, RT9, BFTC905 and TCCSUP. However, its expression level in HUC is negligible. This result suggested that IGFBP-5 might participate in urothelial oncogenesis (figure 5).
(Enlarge Image)
Figure 5.
Western blotting was used to assess IGFBP-5 protein expressing in human urothelial cancer cell lines. IGFBP-5 expression was abundant in cancer cells (RT4, TSGH8301, J82, RT9, BFTC905 and TCCSUP), but was barely detected in normal human urothelial cells.
Results
IGFBP5 Identified as a Significant Differentially Upregulated Transcript Implicating Dysregulation of the Cell Growth in UBUC
From the transcriptomic profile of 33 high-staged and metastatic cases and 16 low-staged and non-metastatic ones of UBUC, 26 probes covering 21 transcripts associated with regulation of cell growth (GO:0001558) were found (figure 1). The log2 ratios of one transcript met the selection criteria of >1.5 increase (p<0.0001), that is, IGFBP5, with log2 ratio of 1.7363 to 3.3334-fold upregulation (Table 1). Of note, the expression level of IGFBP5 transcript significantly predicted DSS (figure 2, p=0.0120). Detailed information is provided in the online supplementary data.
(Enlarge Image)
Figure 1.
The transcriptome of urinary bladder urothelial carcinomas reconstructed from GSE31684 with focusing on those involving regulation of cell growth (GO: 0001558). The expression levels of 26 probes targeting 21 genes were identified to be significantly different (p<0.01, Log2 ratio >+/0.1) by comparing 33 high-staged (pT2-T4) and metastasising tumour and 16 low-staged (pT0-T1) and non-metastasising lesions.
(Enlarge Image)
Figure 2.
Clinicopathological Findings of the UTUC and UBUC
The clinicopathological findings of the UTUC and UBUC cases are listed in Table 2. Detailed information is provided in the online supplementary data.
Correlations of immunoreactivity of IGFBP-5 With Parameters in the UTUC and UBUC
IGFBP-5 shows variable cytoplasmic expression in the UC of both locations with H-scores in the range of 155 to 485 (median 340) for UTUC and 150 to 490 (median 345) for UBUC. After dichotomising the tumour into low and high IGFBP-5 expression (H-score less than median and no less than median, respectively), as demonstrated in Table 2, increased IGFBP-5 expression showed significant association with increment of pT status (figure 3), lymph node metastasis, a high histological grade, vascular invasion, perineural invasion and frequent mitosis in UC for either location. Detailed information is provided in the online supplementary data.
(Enlarge Image)
Figure 3.
Representative H&E sections of low-stage urothelial carcinoma (UC) (A) demonstrated low cytoplasmic IGFBP-5 expression (C), whereas the high-stage, infiltrating UC (B) shows bright IGFBP-5 expression (D).
Survival Analysis of UTUC
The univariate and multivariate analyses of the associations of the clinical outcomes with various clinicopathological in UTUC and UBUC cases are demonstrated in Table 3 and Table 4 respectively. Detailed information is provided in the online supplementary data.
Prognostic Impact of IGFBP-5 Expression in UCs
Univariate and multivariate analyses (Table 3 and Table 4 and figure 4) showed that high IGFBP-5 cytoplasmic expression was significantly associated with worse DSS and MeFS in patients with UTUC or UBUC. Detailed information is provided in the online supplementary data.
(Enlarge Image)
Figure 4.
Kaplan-Meier plots show that IGFBP-5 overexpression conferred significant prognostic impacts in disease-specific survival and metastasis-free survival of patients with upper urinary tract urothelial carcinoma (A and B, respectively) and urinary bladder urothelial carcinoma (C and D, respectively).
IGFBP-5 is More Abundant in Urothelial Tumour Cells Than Primary Urothelial Cells
According to the western blot analysis, IGFBP-5 protein is detected in urothelial cancer cells including RT4, TSGH8301, J82, RT9, BFTC905 and TCCSUP. However, its expression level in HUC is negligible. This result suggested that IGFBP-5 might participate in urothelial oncogenesis (figure 5).
(Enlarge Image)
Figure 5.
Western blotting was used to assess IGFBP-5 protein expressing in human urothelial cancer cell lines. IGFBP-5 expression was abundant in cancer cells (RT4, TSGH8301, J82, RT9, BFTC905 and TCCSUP), but was barely detected in normal human urothelial cells.
Source...