Expression and Prognostic Value of Lgr5 in Patients with Recurrent Nasopharyngeal Carcinoma

Figures & data

Figure 1 mRNAs expression profile in rNPC tissues compared to normal tissues. (A) Heat maps with hierarchical clustering analysis show 30 differentially expressed mRNAs (15 up-regulated and 15 down-regulated mRNAs) on the RNA-seq analysis. The histogram on the upper right is in color order. The color change from top to bottom indicates high-to-low mRNA expression in the sample; (B) Volcano plots of the differentially expressed mRNAs. Horizontal dotted line: q=0.05 (–log10 scaled); red points: upregulated mRNAs with statistical significance; green points: downregulated mRNAs with statistical significance; (C) Representative imaging of IHC showing the expression of Lgr5 in the rNPC, primary NPC and normal tissue samples (original magnification×200); (D) IHC staining score of Lgr5 was significantly higher in the rNPC tissues, compared to the primary NPC tissues and the normal tissues; (E) Representative imaging of IHC showing expression of Lgr5 in different T stages of rNPC. (F) Western blotting showed the expression of Lgr5 in 6 pairs of rNPC and non-cancer tissues.

Abbreviations: rNPC, recurrent nasopharyngeal carcinoma; IHC, immunohistochemistry.

Table 1 Correlation Between Lgr5 and Clinical Characteristics in 60 rNPC Patients

Variables	Lgr5 Expression Level		P value
	Low	High
Gender			0.735
Male	19	23
Female	9	9
Age			0.916
<50	11	13
≥50	17	19
Smoking history			0.785
No	21	23
Yes	7	9
Drinking history			0.796
No	22	26
Yes	6	6
Histological type			0.855
WHO type II	9	11
WHO type III	19	21
T stage			0.014
T1+T2	21	14
T3+T4	7	18
LNM			0.193
No	25	24
Yes	3	8
Tumor necrosis			0.066
No	25	22
Yes	3	10

Abbreviations: rNPC, recurrent nasopharyngeal carcinoma; LNM, lymph node metastasis.

Table 2 Univariate and Multivariate Cox Regression Analyses of OS in Patients with rNPC

Variable	Univariate			Multivariate
	HR	95% CI	P	HR	95% CI	P
The expression of Lgr5
Low expression	1		0.019	1		0.035
High expression	6.047	1.351–27.074		5.435	1.130–26.147
T stage
T1+T2	1		0.095	1		0.997
T3+T4	2.491	0.854–7.266		1.002	0.248–4.052
Tumor necrosis
No	1		0.021	1		0.304
Yes	3.911	1.226–12.478		1.967	0.542–7.136
Histological type
WHO type II	1		0.054	1		0.129
WHO type III	0.344	0.116–1.019		0.370	0.102–1.336
Gender
Male	1		0.488
Female	1.473	0.493–4.402
Age
<50	1		0.136
≥50	2.644	0.737–9.49
Smoking history
No	1		0.693
Yes	0.772	0.214–2.787
Drinking history
No	1		0.799
Yes	1.182	0.326–4.288
LNM
No	1		0.452
Yes	1.564	0.488–5.014

Abbreviations: rNPC, recurrent nasopharyngeal carcinoma; OS, overall survival; LNM, lymph node metastasis.

Table 3 Univariate and Multivariate Cox Regression Analyses of DFS in Patients with rNPC

Variable	Univariate			Multivariate
	HR	95% CI	P	HR	95% CI	P
The expression of Lgr5
Low expression	1		0.002	1		0.018
High expression	3.279	1.536–7.002		2.711	1.188–6.188
T stage
T1+T2	1		0.039	1		0.690
T3+T4	2.087	1.040–4.189		1.186	0.513–2.744
Tumor necrosis
No	1		0.016	1		0.281
Yes	2.518	1.184–5.355		1.618	0.674–3.881
Gender
Male	1		0.205
Female	1.591	0.776–3.260
Age
<50	1		0.458
≥50	0.767	0.380–1.546
Smoking history
No	1		0.977
Yes	0.988	0.443–2.203
Drinking history
No	1		0.860
Yes	0.923	0.379–2.249
Histological type
WHO type II	1		0.903
WHO type III	0.956	0.460–1.984
LNM
No	1		0.582
Yes	1.267	0.546–2.939

Abbreviations: rNPC, recurrent nasopharyngeal carcinoma; DFS, disease free survival; LNM, lymph node metastasis.

Figure 2 Kaplan-Meier curve pertaining to the survival in patients with rNPC. (A) Overall survival; (B) Disease-free survival.

Abbreviation: rNPC, recurrent nasopharyngeal carcinoma.

Figure 3 Kaplan-Meier curves pertaining to the OS in patients with rNPC. (A) Lgr5 expression (high expression vs Low expression); (B) T stage (T1+T2 vs T3+T4); (C) Tumor necrosis; (D) Gender; (E) age (<50 vs ≥50); (F) Smoking history; (G) Drinking history; (H) Histological type; (I) Lymph node metastasis.

Abbreviations: rNPC, recurrent nasopharyngeal carcinoma; OS, overall survival.

Figure 4 Kaplan-Meier curves pertaining to the DFS in patients with rNPC. (A) Lgr5 expression (High expression vs Low expression); (B) T stage (T1+T2 vs T3+T4); (C) Tumor necrosis; (D) Gender; (E) age (<50 vs ≥50); (F) Smoking history; (G) Drinking history; (H) Histological type; (I) Lymph node metastasis.

Abbreviations: rNPC, recurrent nasopharyngeal carcinoma; DFS, disease-free survival.

Figure 5 Receiver operating characteristic analysis revealed that Lgr5 expression had good predictive value as a predictor of survival and recurrence in rNPC patients. The area under the ROC curve was 0.711 (A) (P=0.017) and 0.665 (B) (P=0.028), respectively.

Abbreviations: rNPC, recurrent nasopharyngeal carcinoma; ROC, receiver operating characteristic.