Long non-coding RNA MCF2L-AS1 promotes the aggressiveness of colorectal cancer by sponging miR-874-3p and thereby up-regulating CCNE1.

BACKGROUND: Long non-coding RNAs (lncRNAs) have drawn growing attention because of the role which they play in various diseases, including colorectal cancer (CRC). However, the potential functions of lncRNA MCF2L antisense RNA 1 (MCF2L-AS1) in tumors remained largely unclear. The present study aimed to explore the clinical significance and the biological effects of lncRNA MCF2L antisense RNA 1 (MCF2L-AS1) in CRC. METHODS: Reverse transcriptase-polymerase chain reaction was performed to determine the expression of MCF2L-AS1 in CRC. The clinical significance of MCF2L-AS1 in CRC patients was analyzed statistically. In vitro experiments were performed to determine the effects of MCF2L-AS1 on the cellular progression of CRC cells. Bioinformatic assays, luciferase reporter assays and RNA-pulldown assays were performed to predict for potential microRNAs that can interact with MCF2L-AS1 and mRNAs that can interact with miR-874-3p. RESULTS: We identified a novel CRC-related lncRNA, MCF2L-AS1, which is distinctly highly expressed in CRC. Its diagnostic value for CRC patients was also demonstrated. Clinical assays revealed that high MCF2L-AS1 expression is associated with advanced stages, positive metastasis and the poor prognosis of CRC patients. Multivariate assays confirmed that MCF2L-AS1 expression is an independent poor prognostic factor for both 5-year overall survival and 5-year disease-free survival of CRC patients. Functionally, we confirmed that knockdown of MCF2L-AS1 distinctly suppresses the proliferation, migration and invasion of CRC cells and also promotes apoptosis. Mechanistic investigation showed that MCF2L-AS1 functions as an endogenous sponge for miR-874-3p to increase the expression of CCNE1. CONCLUSIONS: Our findings identified a novel CRC-related lncRNA, MCF2L-AS1, which may be used as a potential diagnostic and prognostic biomarker for CRC patients. In addition, the newly identified MCF2L-AS1/miR-874-3p/CCNE1 axis can modulate the initiation and progression of CRC.

[Effect of sorafenib on lymphangiogenesis in subcutaneously transplanted human cholangiocarcinoma in nude mice].

OBJECTIVE: To study the effects of sorafenib on lymphangiogenesis in transplanted human cholangiocarcinoma in nude mice. METHODS: The model of transplanted human cholangiocarcinoma in nude mice was established by subcutaneous inoculation of cholangiocarcinoma cell line QBC 939 cells. Thirty-six nude mice were randomly divided into 3 groups after tumor formation: control group, sorafenib 30 mg × kg⁻¹ × d⁻¹ group and sorafenib 60 mg × kg⁻¹ × d⁻¹ group (n = 12 each), and then treated by gavage for 6 weeks. The tumor growth of the dose groups and control group was measured with calipers. Using immunohistochemical staining, the lymphatic microvessels at tumor edge were marked by LYVE-1 and counted. The expression of VEGFR-3 mRNA in paracancerous tissues was evaluated by RT-PCR. RESULTS: Sorafenib significantly depressed the growth of cholangiocarcinoma. The inhibitory rate in the sorafenib 30 mg × kg⁻¹ × d⁻¹ group and 60 mg × kg⁻¹ × d⁻¹ group was 55.1% and 67.9%, respectively. The LMVDs of the control group, sorafenib 30 mg × kg⁻¹ × d⁻¹ group and 60 mg × kg⁻¹ × d⁻¹ group were 11.75 ± 3.19, 6.84 ± 2.18 and 5.03 ± 1.91, respectively. The LMVD of the control group was significantly higher than that in the dose groups (P < 0.01). The relative expressions of VEGFR-3 mRNA in the control group, sorafenib 30 mg × kg⁻¹ × d⁻¹ group and 60 mg × kg⁻¹ × d⁻¹ group were 2.158 ± 0.312, 1.027 ± 0.144 and 0.736 ± 0.149, respectively. The relative expression of VEGFR-3 mRNA in the control group was significantly higher than that in the dose groups (P < 0.05). No occurrence of lymph node metastasis was found in all groups. CONCLUSION: Sorafenib can significantly inhibit the growth of xenograft cholangiocarcinoma in nude mice. Sorafenib may reduce LMVD by down-regulation of the expression of VEGF-C/D and VEGFR-3 signaling axis.