Long noncoding RNA LINC01296 is associated with poor prognosis in prostate cancer and promotes cancer-cell proliferation and metastasis

Figures & data

Figure 1 Relative LINC01296 expression in prostate cancer.

Notes: (A) A microarray containing 8277 lncRNA probes was used to identify differentially expressed lncRNAs in three prostate cancer patients. (B) Relative expression of LINC01296 in prostate cancer tissues compared with paired adjacent normal tissues. (C) Relative expression of LINC01296 in prostate cancer cell lines (22Rv1, LNCaP) and normal prostate cell line (WPMY1). Each experiment was repeated three times. **P<0.01.
Abbreviation: lncRNA, long noncoding RNA.

Table 1 The association between LINC01296 expression and clinicopathological features of prostate cancer

	Total (%)	LINC01296 expression		P-value
		Low (%)	High (%)
Age (years)				0.569
<65	14 (20)	4 (28.6)	10 (71.4)
≥65	56 (80)	12 (21.4)	44 (78.6)
Prostate volume (cm^3)				0.794
<50	37 (52.9)	8 (21.6)	29 (78.4)
≥50	33 (47.1)	8 (24.2)	25 (75.8)
Preoperative PSA (ng/mL)				0.002
<10	29 (41.4)	12 (41.4)	17 (48.6)
≥10	41 (58.6)	4 (9.8)	37 (90.2)
Lymph-node metastasis				0.035
Presence	38 (54.3)	5 (13.2)	33 (86.8)
Absence	32 (45.7)	11 (34.4)	21 (65.6)
Gleason score				0.001
<7	23 (32.9)	12 (52.2)	11 (47.8)
≥7	47 (67.1)	4 (8.5)	43 (91.5)
Tumor stage				0.036
T2	28 (40)	10 (35.7)	18 (64.3)
T3–T4	42 (60)	6 (14.3)	36 (85.7)
Multiple lesions				0.171
Presence	43 (61.4)	9 (20.9)	34 (79.1)
Absence	27 (38.6)	7 (25.9)	20 (74.1)

Abbreviation: PSA, prostate specific antigen.

Figure 2 Kaplan–Meier survival curves of two groups of patients with prostate cancer based on LINC01296-expression levels (P=0.01).

Note: Patients with high levels of LINC01296 expression showed reduced biochemical recurrence-free survival times compared with patients with low levels of LINC01296 expression.

Table 2 Cox proportional-hazard model of biochemical recurrence-free survival in prostate cancer

	Univariate analysis			Multivariate analysis
	HR	95% CI	P-value	HR	95% CI	P-value
Age (years)			0.675
≥65 vs <65	1.18	0.545–2.552
Prostate volume (cm^3)			0.78
≥50 vs <50	0.911	0.476–1.746
Preoperative PSA (ng/mL)			0.09
≥10 vs <10	1.879	0.906–3.898
Lymph-node metastasis			0.406
Presence vs absence	1.319	0.687–2.535
Gleason score			0.006			0.041
≥7 vs <7	3.429	1.426–8.247		2.965	1.047–8.397
Tumor stage			0.491
T3–T4 vs T2	1.272	0.642–2.519
Multiple lesions			0.514
Presence vs absence	0.799	0.407–1.569
LINC01296 expression			0.002			0.044
High vs low	6.584	1.951–22.224		4.003	1.038–15.67

Abbreviations: HR, hazard ratio; CI, confidence interval; PSA, prostate specific antigen.

Figure 3 siRNA-mediated knockdown of LINC01296 inhibited prostate cancer-cell proliferation.

Notes: (A) Relative expression levels of LINC01296 in 22Rv1 and LNCaP cells were significantly decreased by siLINC01296 compared with the NC. (B) CCK-8 assays were performed to determine the proliferation of 22Rv1 and LNCaP cells after transfection. (C, D) Colony-formation assays were performed to determine the proliferation of siLINC01296-transfected 22Rv1 and LNCaP cells. Colonies were counted and captured. (E–G) Western blot was performed to analyze relative protein-expression levels of the PI3K–Akt–mTOR signaling pathway in siLINC01296-transfected 22Rv1 and LNCaP cells and respective control cells. Data represent mean ± standard deviation from three independent experiments. *P<0.05; **P<0.01.
Abbreviations: siRNA, short interfering RNA; NC, negative control; OD, optical density; GAPDH, glyceraldehyde 3-phosphate dehydrogenase; SI, short interfering RNA1; S2, short interfering RNA2.

Figure 4 siRNA-mediated knockdown of LINC01296 inhibited prostate cancer-cell migration and invasion.

Notes: Prostate cancer cells transfected with siLINC01296 displayed significantly lower migration (A, B) and invasion (C, D) capacity compared with those transfected with siNC. Data represent mean ± standard deviation from three independent experiments. (E–G) Western blot was performed to analyze of vimentin, N-catenin, E-cadherin, and MMP9 protein-expression levels in siLINC01296-transfected 22Rv1 and LNCaP cells and respective control cells. Data represent mean ± standard deviation from three independent experiments. *P<0.05.
Abbreviations: siRNA, short interfering RNA; NC, negative control; GAPDH, glyceraldehyde 3-phosphate dehydrogenase; SI, short interfering RNA1; S2, short interfering RNA2.