LncRNA DIO3OS was significantly lower in hepatocellular carcinoma
We used wilcoxon rank sum test to investigate the expression differences of DIO3OS in a variety of tumors (Fig.1a). Then, we compared the DIO3OS expression in tumor and normal samples. As the result demonstrated that DIO3OS expression was notably declined in HCC patients (P<0.001) (Fig.1b). Futhermore, we investigated the DIO3OS expression in 50 pairs of tumor tissues and normal adjacent liver tissues by paired sample t-test (Fig.1c). The results showed that DIO3OS levels were significantly lower in various types of tumors than in normal tissue. Not only that, the differental analysis of the expression of this lncRNA between tumor samples and normal samples of HCC also proved that a significant decrease in the level of DIO3OS in HCC (P < 0.001).
Fig. 1. LncRNA DIO3OS expression status in vatious of cancers. a. The expression level of DIO3OS in various cancer tissues. b. Comparison of DIO3OS in normal tissues(n=50) and cancer tissues(n=374) of hepatocellular carcinoma. c. Differential expression of DIO3OS in paired hepatocellular carcinoma cancer tissues(n=50) and normal tissues(n=50).(*P<0.005, ***P<0.001)
Low DIO3OS level predicts poor prognosis in HCC patients
Kaplan-Meier curves can describe patients’ survival. As shown in Fig 2a-c, after analyzing the relationship between DIO3OS expression and survival probability and survival time in patients’ OS (HR=0.63, p=0.024), DFS (HR=0.56, p=0.015) and PFI (HR=0.70, p=0.016), it can be concluded that a high level of DIO3OS is a favorable indicator for patients’ higher survival rate.
The results of the Cox regression analysis are shown in Fig 2d and 2e, the size and extent of tumorinvasion (HR=2.598, P<0.001), tumor status (HR=0.432, P<0.001), pathological stage (HR=2.504, P<0.001) and DIO3OS expression (HR=0.777, P=0.017) were significantly correlated with poor OS in HCC patients. Among them, high level of DIO3OS is a protective factor for HCC patients. And multivariate analysis revealed that tumor status (HR=0.561, P=0.005) was an independent predictor for negtive prognosis (Figure. 2E). This findings suggest that low-level DIO3OS is closely related to the process and variation of HCC.
Fig. 2. Low expression of lncRNA DIO3OS is associated with poor OS, DSS and PFI in patients with hepatocellular carcinoma. a. Overall survival (n=373), b. disease specific survival (n=365), c. progress free interval (n=373). d. Multivariate Cox regression analysis is used to determine the effect of selected variables on OS. e.Univariate Cox regression analysis is used to determine the effect of selected variables on OS.
GSEA identifies biological functions related to DIO3OS
The Fig.3 and Tab.1 showed that DIO3OS was closely related to multiple immune-related signaling pathways. Including the following seven signaling pathways, IL8 signaling pathway, immunoreulatory interactions between a lymphoid and a nonlymphoid cell, TGFβ signaling pathway, interleukin 4 and interleukin 13 signaling, WNT signaling pathway, JAK/STAT signaling pathway, leukocyte transendothelial migration. In addition, neutrophil degranulation, PI3K/AKT signaling pathway, EMC receptor interaction, notch pathway also showed significant enrichment in the DIO3OS high expression group.
Fig. 3. Enrichment plots from gene set enrichment analysis (GSEA). a. neutrophil degranulation, immunoregulatory interactions between a lymphoid and a non lymphoid cell, interleukin 4 and interleukin 13 signaling. b. PI3K/AKT signaling pathway, IL 18signaling pathway, NOTCH pathway. c. ECM receptor interaction, TGFβ signaling pathway, WNT signaling pathway, JAK/STST signaling pathway, leukocyte transendothelial migration.
Tab.1 Gene sets enriched in high phenotype
Description
|
NES
|
p.val
|
FDR q values
|
REACTOME_NEUTROPHIL_DEGRANULATION
|
1.469
|
0.001
|
0.019
|
REACTOME_IMMUNOREGULATORY_INTERACTIONS_BETWEEN_A
_LYMPHOID_AND_A_NON_LYMPHOID_CELL
|
1.715
|
0.001
|
0.018
|
REACTOME_INTERLEUKIN_4_AND_INTERLEUKIN_13_SIGNALING
|
1.674
|
0.001
|
0.018
|
WP_PI3KAKT_SIGNALING_PATHWAY
|
1.832
|
0.001
|
0.018
|
WP_IL18_SIGNALING_PATHWAY
|
1.503
|
0.001
|
0.018
|
PID_NOTCH_PATHWAY
|
1.611
|
0.001
|
0.018
|
KEGG_ECM_RECEPTOR_INTERACTION
|
1.979
|
0.001
|
0.018
|
KEGG_TGF_BETA_SIGNALING_PATHWAY
|
1.838
|
0.001
|
0.018
|
KEGG_WNT_SIGNALING_PATHWAY
|
1.744
|
0.001
|
0.018
|
KEGG_JAK_STAT_SIGNALING_PATHWAY
|
1.618
|
0.001
|
0.018
|
KEGG_LEUKOCYTE_TRANSENDOTHELIAL_MIGRATION
|
1.472
|
0.003
|
0.035
|
NES: normalized enrichment score after correction. p value: p values of statistical tests. FDR q-value: the corrected q-value obtained by the p-value correction method. The threshold of significant enrichment: false discovery rate (FDR) <0.25 and p. value<0.05.
Association with DIO3OS expression and immune infiltration in hepatocellular carcinoma
From the “ESTIMATE” analysis, we can draw the following conclusions. As shown in Fig 4a, both immune scores and matrix scores were significantly higher in the high DIO3OS expression group than in the low DIO3OS expression group. The immune score represents the content of immune cells in the tumor, and the stromal score represents the content of stromal cells. This suggests that the number of immune cells in the tumor is relatively reduced when DIO3OS levels are reduced.
According to the document of Bindea et al.(Bindea, et al., 2013), we selected 24 kinds of immune cells to investigate the correlation between DIO3OS expression and immune cells. Figure 4b and table 2 illustrate that in HCC, DIO3OS is associated with NK cells, mast cells, two types of DC cells (iDC, pDC), five types of T cells (Tem, TFH, CD8 T cells, Th1 cells, Tgd), eosinophils, macrophages, B cells, NK CD56 bright cells were significantly positively correlated, and Treg cells were significantly negatively correlated. This result is consistent with that of the ESTIMATE analysis.
As Tab.3 and supplement figures showed that the DIO3OS expression had positive correlation with CD40LG (r=0.212, p=3.6e-05), LTK (r=0.425, p=76e-18), OSBPL5 (r=0.406, p=2.5e-16), CD19 (r=0.128, p=0.013), CD79A (r=0.194, p=1.64e-04), PTPRC (r=0.142, p=0.006), CCR4 (r=0.286, p=2.94e-04), B3GAT1 (r=0.366, p=2.75e-03), CXCR3 (r=0.113, p=0.029), IL7R (r=0.286, p=1.87e-08), ITGAE (r=0.254, p=1.6e-06), CD123 (r=0.228, p=8.78e-06), CD83 (r=0.189, p=2.39e-04), HLA-DR (r=0.136, p=0.009), HLA-DMB (r=0.132, p=0.011), HLA-DPB1 (r=0.174, p=7.21e-04), HLA-DQA1 (r=0.145, p=0.005), HLA-DQB1 (r=0.140, p=0.007), HLA-DRB1 (r=0.136, p=0.009), HLA-DRB5 (r=0.114, p=0.028). In addition, a significant negative correlation with FOXP3 (r=-0.127, p=0.014), CD40 (r=-0.191, p=2.07e-04), DPP4 (r=-0.17, p=9.89e-04) was observed.
Fig. 4. Correlation analysisi between the degree of immune cell infiltration and the expression of lncRNA DIO3OS in hepatocellular carcinoma tissues. a. Density of immune cells in tumor samples. b. Correlation analysis between various immune cells and lncRNA DIO3OS.( *P<0.005, **P<0.01, ***P<0.001)
Table.2 Correlation analysis between DIO3OS and related immune cells in HCC.
Description
|
Correlation
|
P value
|
NK cells
|
0.310
|
<0.001
|
Mast cells
|
0.286
|
<0.001
|
iDC
|
0.266
|
<0.001
|
Tem
|
0.259
|
<0.001
|
Eosinophil
|
0.227
|
<0.001
|
TFH
|
0.218
|
<0.001
|
Macrophages
|
0.215
|
<0.001
|
B cells
|
0.205
|
<0.001
|
CD8 T cells
|
0.189
|
<0.001
|
NK CD56bright cells
|
0.180
|
<0.001
|
Treg
|
-0.144
|
0.005
|
T cells
|
0.141
|
0.006
|
Th1 cells
|
0.141
|
0.006
|
pDC
|
0.133
|
0.010
|
Tgd
|
0.131
|
0.011
|
DC
|
0.119
|
0.022
|
Cytotoxic cells
|
0.096
|
0.063
|
Neutrophils
|
0.085
|
0.102
|
NK CD56dim cells
|
0.053
|
0.311
|
T helper cells
|
0.039
|
0.456
|
Tcm
|
-0.037
|
0.474
|
Th17 cells
|
-0.032
|
0.542
|
Th2 cells
|
0.018
|
0.729
|
aDC
|
0.002
|
0.964
|
Statistically significant value : P < 0.05.
Tab.3 Correlation analysis between DIO3OS and related biomarker genes of immune cells.
Description
|
Gene Markers
|
correlation
|
P value
|
T Cells
|
CD4
|
0.160
|
0.002
|
|
CD40LG/CD40L
LTK
|
0.212
0.425
|
3.6e-05
7.6e-18
|
|
OSBPL5
|
0.406
|
2.5e-16
|
B Cells
|
CD19
|
0.128
|
0.013
|
|
CD79A
|
0.194
|
1.64e-04
|
|
PTPRC
|
0.142
|
0.006
|
|
CD40
|
-0.191
|
2.07e-04
|
Treg Cells
|
FOXP3
|
-0.127
|
0.014
|
|
NINJ2
|
-0.219
|
1.84e-05
|
|
CD25
CDKN2A
|
0.076
-0.282
|
0.14
3.03e-08
|
|
CCR4
PRDX1
|
0.286
-0.274
|
2.94e-04
6.97e-08
|
Natural killer cells
|
B3GAT1
|
0.366
|
2.75e-03
|
|
CXCR3
|
0.113
|
0.029
|
|
IL7R
|
0.286
|
1.87e-08
|
|
ITGAE
|
0.254
|
1.60e-06
|
|
DPP4
|
-0.17
|
9.89e-04
|
|
NCR3/NKP30
|
0.148
|
0.004
|
Dendritic cells
|
CD123
|
0.228
|
8.78e-06
|
|
CD83
|
0.189
|
2.39e-04
|
|
HLA-DR
|
0.136
|
0.009
|
|
HLA-DMB
|
0.132
|
0.011
|
|
HLA-DPB1
|
0.174
|
7.21e-04
|
|
HLA-DQA1
|
0.145
|
0.005
|
|
HLA-DQB1
|
0.140
|
0.007
|
|
HLA-DRB1
HLA-DRB5
|
0.136
0.114
|
0.009
0.028
|