The long non-coding RNA PCAL7 promotes prostate cancer by strengthening androgen receptor signaling

Interaction between Non-Coding RNAs and Androgen Receptor with an Especial Focus on Prostate Cancer

The androgen receptor (AR) is a member of the nuclear receptor superfamily and has three functional domains, namely the N-terminal, DNA binding, and C-terminal domain. The N-terminal domain harbors potent transactivation functions, whereas the C-terminal domain binds to androgens and antiandrogens used to treat prostate cancer. AR has genomic activity being DNA binding-dependent or through interaction with other DNA-bound transcription factors, as well as a number of non-genomic, non-canonical functions, such as the activation of the ERK, AKT, and MAPK pathways. A bulk of evidence indicates that non-coding RNAs have functional interactions with AR. This type of interaction is implicated in the pathogenesis of human malignancies, particularly prostate cancer. In the current review, we summarize the available data on the role of microRNAs, long non-coding RNAs, and circular RNAs on the expression of AR and modulation of AR signaling, as well as the effects of AR on their expression. Recognition of the complicated interaction between non-coding RNAs and AR has practical importance in the design of novel treatment options, as well as modulation of response to conventional therapeutics.

Emerging role of long noncoding RNAs in recurrent hepatocellular carcinoma

Hepatocellular carcinoma (HCC) remains one of the most frequent types of liver cancer and is characterized by a high recurrence rate. Recent studies have proposed that long non-coding RNAs (lncRNAs) are potential biomarkers in several recurrent tumor types. It is now well understood that invasion, migration, and metastasis are important factors for tumor recurrence. Moreover, some of the known risk factors for HCC may affect the expression levels of several types of lncRNAs and thus affect the recurrence of liver cancer through lncRNA regulation. In this paper, we review the biological functions, molecular mechanisms, and roles of lncRNAs in HCC and summarize current knowledge about lncRNAs as potential biomarkers in recurrent HCC.

LncRNA FGF14-AS2 represses growth of prostate carcinoma cells via modulating miR-96-5p/AJAP1 axis

OBJECTIVE

This investigation devoted to lncRNA FGF14 antisense RNA 2 (FGF14-AS2) in prostate carcinoma progression.

METHODS

The levels of lncRNA FGF14-AS2, miR-96-5p, and Adherens junction-associated protein-1 (AJAP1) in prostate carcinoma were tested by Western blot and qRT-PCR. How these two genes interacted was confirmed by RNA immunoprecipitation and dualluciferase gene methods. The effect of FGF14-AS2/miR-96-5p/AJAP1 axis in prostate carcinoma progression was determined by MTT, Transwell, and nude mice tumor model.

RESULTS

FGF14-AS2 was a downregulated lncRNA in prostate carcinoma tissue and cells. FGF14-AS2 could restrain miR-96-5p expression while miR-96-5p hampered AJAP1. FGF14-AS2 could effectively decrease the biological behaviors of prostate carcinoma cells, while knock-down of FGF14-AS2 triggered opposite results. Moreover, miR-96-5p mimic presented a cancer promoter role in prostate carcinoma cells. AJAP1 expression level could affect levels of proteins related to epithelial-mesenchymal transition. In vivo experiment suggested that overexpressing FGF14-AS2 could reverse the promotion of silenced AJAP1 on prostate carcinoma cell metastasis, thus to inhibit tumor growth.

CONCLUSION

lncRNA FGF14-AS2 was a downregulated lncRNA in prostate carcinoma and influenced cell proliferation and metastasis. The influence relied on modulating miR-96-5p and its target gene AJAP1.

The long non-coding RNA PCAL7 promotes prostate cancer by strengthening androgen receptor signaling

BACKGROUND

The prostate cancer (PCa) has been a global problem to men health. Notably, the androgen receptor (AR) is essential for both normal development of prostate and prostate cancer progression.

METHODS

The RNA sequencing was used to identify the novel long non-coding RNA (lncRNA) termed PCAL7. The RT-qPCR was performed to quantify PCAL7 expression. Migration and proliferation assays were used to examine the function of PCAL7. Fluorescence in situ hybridization (FISH) was used to determine subcellular localization.

RESULTS

By RNA sequencing, the differentially expressed lncRNAs were identified (top 10 upregulated lncRNAs: PCAL7, AC083843.1, CTC-338M12.3, RP11-443B7.1, RP11-1008C21.2, RN7SL329P, RP4-773N10.4, RP11-264B17.2, KB-1507C5.2, and RP11-20B24.6; top 10 downregulated lncRNAs: RP11-77H9.2, RAB11FIP1P1, AP001625.6, CTA-217C2.1, RP11-603J24.7, RP11-315I20.1, AC092839.1, RP4-758J18.10, RP11-259O2.3, and HMGN2P17). PCAL7 was the lncRNA with the highest fold upregulation and significantly correlated with AR signaling during prostate cancer progression. The AR-regulated PCAL7 was abundantly overexpressed in prostate cancer tissues and AR-dependent cell lines. PCAL7 knockdown inhibited cell migration and proliferation. Consistently, the migration and proliferation were promoted by PCAL7 overexpression. PCAL7 depletion via antisense oligonucleotides (ASOs) markedly suppressed AR signaling and tumor growth. Mechanistically, PCAL7 interacted with Huntingtin-interacting protein 1 (HIP1) to stabilize HIP1. Therefore, PCAL7 could advance AR signaling via a novel positive feedback loop.

CONCLUSION

Our experiments support an oncogenic role for PCAL7 which promotes prostate cancer progression suggesting PCAL7 may serve as a potential therapeutic target.