Long noncoding RNAs (lncRNAs) in cervical carcinogenesis: New molecular targets, current prospects

LncRNA HOXC-AS3 accelerates malignant proliferation of cervical cancer cells via stabilizing KDM5B

BACKGROUND

Cervical cancer (CC) is a common malignancy amongst women globally. Ubiquitination plays a dual role in the occurrence and development of cancers. This study analyzed the mechanism of long noncoding RNA HOXC cluster antisense RNA 3 (lncRNA HOXC-AS3) in malignant proliferation of CC cells via mediating ubiquitination of lysine demethylase 5B (KDM5B/JARID1B).

METHODS

The expression patterns of lncRNA HOXC-AS3 and KDM5B were measured by real-time quantitative polymerase chain reaction or Western blot analysis. After transfection with lncRNA HOXC-AS3 siRNA and pcDNA3.1-KDM5B, proliferation of CC cells was assessed by the cell counting kit-8, colony formation, and 5-Ethynyl-2'-deoxyuridine staining assays. The xenograft tumor model was established to confirm the impact of lncRNA HOXC-AS3 on CC cell proliferation in vivo by measuring tumor size and weight and the immunohistochemistry assay. The subcellular location of lncRNA HOXC-AS3 and the binding of lncRNA HOXC-AS3 to KDM5B were analyzed. After treatment of lncRNA HOXC-AS3 siRNA or MG132, the protein and ubiquitination levels of KDM5B were determined. Thereafter, the interaction and the subcellular co-location of tripartite motif-containing 37 (TRIM37) and KDM5B were analyzed by the co-immunoprecipitation and immunofluorescence assays.

RESULTS

LncRNA HOXC-AS3 and KDM5B were upregulated in CC tissues and cells. Depletion of lncRNA HOXC-AS3 repressed CC cell proliferation and in vivo tumor growth. Mechanically, lncRNA HOXC-AS3 located in the nucleus directly bound to KDM5B, inhibited TRIM37-mediated ubiquitination of KDM5B, and upregulated the protein levels of KDM5B. KDM5B overexpression attenuated the inhibitory role of silencing lncRNA HOXC-AS3 in CC cell proliferation in vivo and in vitro.

CONCLUSION

Nucleus-located lncRNA HOXC-AS3 facilitated malignant proliferation of CC cells via stabilization of KDM5B protein levels.

Role of noncoding RNAs with emphasis on long noncoding RNAs as cervical cancer biomarkers

Cervical cancer is a significant public health problem in developing countries, as most cases present at an advanced stage. This review aimed to analyze the role of noncoding RNAs as diagnostic and prognostic biomarkers in cervical cancers. Published studies on specific microRNA signatures in body fluids and cervical cancer tissues are highly heterogeneous, and there are no validated assays. The precision of the various immune-associated long noncoding (lncRNA) signatures should be assessed in clinical samples. Even though lncRNAs are tissue and cancer-specific, safe and appropriate methods for delivery to tumor tissues, toxicities and side effects are to be explored. Few studies have evaluated deregulated lncRNA expression levels with clinicopathological factors in a limited number of clinical samples. Prospective studies assessing the diagnostic and prognostic roles of circulating lncRNAs and P-Element-induced wimpy testis interacting PIWI RNAs (Piwil RNAs) in cervical cancer cases are essential. For the clinical application of lnc-RNA-based biomarkers, comprehensive research is needed as the impact of noncoding transcripts on molecular pathways is complex. The standardization and validation of deregulated ncRNAs in noninvasive samples of cervical cancer cases are needed.

Molecular Mechanisms of HIV Protease Inhibitors Against HPV-Associated Cervical Cancer: Restoration of TP53 Tumour Suppressor Activities

Cervical cancer is a Human Papilloma virus-related disease, which is on the rise in a number of countries, globally. Two essential oncogenes, E6 and E7, drive cell transformation and cancer development. These two oncoproteins target two of the most important tumour suppressors, p53 and pRB, for degradation through the ubiquitin ligase pathway, thus, blocking apoptosis activation and deregulation of cell cycle. This pathway can be exploited for anticancer therapeutic interventions, and Human Immunodeficiency Virus Protease Inhibitors (HIV-PIs) have attracted a lot of attention for this anticancer drug development. HIV-PIs have proven effective in treating HPV-positive cervical cancers and shown to restore impaired or deregulated p53 in HPV-associated cervical cancers by inhibiting the 26S proteasome. This review will evaluate the role players, such as HPV oncoproteins involved cervical cancer development and how they are targeted in HIV protease inhibitors-induced p53 restoration in cervical cancer. This review also covers the therapeutic potential of HIV protease inhibitors and molecular mechanisms behind the HIV protease inhibitors-induced p53-dependent anticancer activities against cervical cancer.

Long noncoding RNA ALOX12-AS1 inhibits cervical cancer cells proliferation via targeting miR-3171

Cervical cancer is a common female malignancy worldwide, and the molecular mechanism of cervical tumorigenesis remains poorly understood. A large piece of evidence have demonstrated the important roles of long noncoding RNAs (lncRNAs) in tumorigenesis, cancer progression and drug resistance. In this study, we comprehensively analyzed the lncRNAs expression pattern in cervical cancer using RNA sequencing and microarray data from the cancer genome atlas, gene expression omnibus and Genotype Tissue Expression. Moreover, we assessed the correlation between lncRNA expression levels and cervical cancer patient's survival. We uncovered hundreds of lncRNAs that are upregulated or downregulated in cervical cancer tissues. Among these aberrantly lncRNAs, some are significantly associated with cervical patients' poorer prognosis, such as ALOX12-AS1 and LINC00173. ALOX12-AS1 expression is downregulated in cervical cancer, and over-expression of ALOX12-AS1 could inhibit cervical cancer cells proliferation in vitro. Further, mechanistically investigation revealed that ALOX12-AS1 could interact with AGO2 and sponge miR-3171, thereby antagonizing its' repression of tumor suppressor phosphatase and tensin homolog expression in cervical cancer cell. Taken together, this study provides lncRNA candidates in cervical cancer and highlights the critical role of ALOX12-AS1 in cervical cancer.

Long non-coding RNA KCNQ1OT1 facilitates the progression of cervical cancer and tumor growth through modulating miR-296-5p/HYOU1 axis

Literature reports that lncRNA KCNQ1OT1 is markedly up-regulated in cervical cancer (CC) tissues and cell lines, and KCNQ1OT1 can promote the proliferation and metastasis of CC cells. This current work was designed to investigate the molecular mechanism underlying the participation of KCNQ1OT1 in CC progression. Herein, RT-qPCR was utilized for determining the levels of KCNQ1OT1, miR-296-5p and HYOU1 in clinical tumor tissue specimens and CC cell lines. Then, starBase predicted the complementary binding sites of KCNQ1OT1 and miR-296-5p or miR-296-5p and HYOU1. Dual-luciferase reporter assay/RIP assay validated the interplays among KCNQ1OT1/miR-296-5p/HYOU1. In addition, CCK-8, wound healing and transwell assays were employed to assess the proliferative, migrative and invasive properties of CC cells. Moreover, nude mice xenograft model was established by subcutaneously injection with SiHa cells in order to validate the precise functions of KCNQ1OT1/miR-296-5p/HYOU1 axis in CC in vivo. Besides, Immunohistochemical staining examined Ki-67 expression in xenograft tumors and western blotting analysis detected expressions of MMP2/9 and Wnt/β-catenin signaling pathway in CC cells and xenograft tumors. Elevated KCNQ1OT1 and HYOU1 as well as reduced miR-296-5p were observed in clinical tumor tissue specimens and CC cell lines. Results revealed that upregulation of miR-296-5p counteracted the enhancing effects of overexpressed KCNQ1OT1 on the proliferative, migrative and invasive abilities of CC cells. Additionally, HYOU1 overexpression abolished the suppressing effects of silenced KCNQ1OT1 on the malignant behaviors of CC cells and tumor growth. To conclude, KCNQ1OT1 could aggravate the malignant behaviors of CC and facilitate tumor growth through modulating miR-296-5p/HYOU1 axis.

Bioinformatic identification of genomic instability-associated lncRNAs signatures for improving the clinical outcome of cervical cancer by a prognostic model

The research is executed to analyze the connection between genomic instability-associated long non-coding RNAs (lncRNAs) and the prognosis of cervical cancer patients. We set a prognostic model up and explored different risk groups' features. The clinical datasets and gene expression profiles of 307 patients have been downloaded from The Cancer Genome Atlas database. We established a prognostic model that combined somatic mutation profiles and lncRNA expression profiles in a tumor genome and identified 35 genomic instability-associated lncRNAs in cervical cancer as a case study. We then stratified patients into low-risk and high-risk groups and were further checked in multiple independent patient cohorts. Patients were separated into two sets: the testing set and the training set. The prognostic model was built using three genomic instability-associated lncRNAs (AC107464.2, MIR100HG, and AP001527.2). Patients in the training set were divided into the high-risk group with shorter overall survival and the low-risk group with longer overall survival (p < 0.001); in the meantime, similar comparable results were found in the testing set (p = 0.046), whole set (p < 0.001). There are also significant differences in patients with histological grades, FIGO stages, and different ages (p < 0.05). The prognostic model focused on genomic instability-associated lncRNAs could predict the prognosis of cervical cancer patients, paving the way for further research into the function and resource of lncRNAs, as well as a key approach to customizing individual care decision-making.

LncCCLM inhibits lymphatic metastasis of cervical cancer by promoting STAU1-mediated IGF-1 mRNA degradation

Cervical cancer (CC) patients with lymph node (LN) metastasis often have an extremely poor prognosis. However, the precise molecular mechanisms involved in LN metastasis of CC remain largely unknown. Herein, through RNA screening, we identified a novel long noncoding RNA (lncRNA), LncCCLM, that was downregulated in cervical cancer tissues and closely associated with lymphatic metastasis in cervical cancer patients. Gain-of-function and loss-of-function studies in CC cells demonstrated that LncCCLM inhibited cervical cancer-associated lymphangiogenesis, and CC cell migration and invasion in vitro and suppressed LN metastasis in vivo, but did not affect the growth of CC cells. Mechanistically, LncCCLM localized in the cytoplasm and interacted with staufen double-stranded RNA binding protein 1 (STAU1), promoting the binding of the STAU1 protein to the 3' untranslated region (3'UTR) of insulin-like growth factor 1 (IGF-1) mRNA, which accelerated the degradation of IGF-1 mRNA and decreased the IGF-1 protein level, ultimately reducing lymphangiogenesis and lymphatic metastasis in cervical cancer. Collectively, our findings suggest that LncCCLM acts as a tumor suppressor and may be used as a prognostic biomarker and therapeutic target for clinical intervention in LN-metastatic cervical cancer.

The prognostic value of an autophagy-related lncRNA signature in hepatocellular carcinoma

Background

lncRNA may be involved in the occurrence, metastasis, and chemical reaction of hepatocellular carcinoma (HCC) through various pathways associated with autophagy. Therefore, it is urgent to reveal more autophagy-related lncRNAs, explore these lncRNAs’ clinical significance, and find new targeted treatment strategies.

Methods

The corresponding data of HCC patients and autophagy genes were obtained from the TCGA database, and the human autophagy database respectively. Based on the co-expression and Cox regression analysis to construct prognostic prediction signature.

Results

Finally, a signature containing seven autophagy-related lncRNAs (PRRT3-AS1, RP11-479G22.8, RP11-73M18.8, LINC01138, CTD-2510F5.4, CTC-297N7.9, RP11-324I22.4) was constructed. Based on the risk score of signature, Overall survival (OS) curves show that the OS of high-risk patients is significantly lower than that of low-risk patients (P = 2.292e−10), and the prognostic prediction accuracy of risk score (AUC = 0.786) is significantly higher than that of ALBI (0.532), child_pugh (0.573), AFP (0.5751), and AJCC_stage (0.631). Moreover, multivariate Cox analysis and Nomogram of risk score are indicated that the 1-year and 3-year survival rates of patients are obviously accuracy by the combined analysis of the risk score, child_pugh, age, M_stage, and Grade (The AUC of 1- and 3-years are 0.87, and 0.855). Remarkably, the 7 autophagy-related lncRNAs may participate in Spliceosome, Cell cycle, RNA transport, DNA replication, and mRNA surveillance pathway and be related to the biological process of RNA splicing and mRNA splicing.

Conclusion

In conclusion, the 7 autophagy-related lncRNAs might be promising prognostic and therapeutic targets for HCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12859-021-04123-6.

LncRNA NOP14-AS1 Promotes Tongue Squamous Cell Carcinoma Progression by Targeting MicroRNA-665/HMGB3 Axis

Purpose

The expression profile, clinical effects, and detailed roles of NOP14 antisense RNA 1 (NOP14-AS1) in tongue squamous cell carcinoma (TSCC) remain ambiguous and need to be further explored. Thus, this work was initiated to offer further solid evidence regarding the expression and roles of NOP14-AS1 in TSCC. Furthermore, additional efforts were exerted to reveal the molecular events by which NOP14-AS1 affects the malignant behaviours of TSCC.

Methods

NOP14-AS1 expression was detected in TSCC tissues and cell lines using quantitative reverse transcription-polymerase chain reaction. Cell Counting Kit-8 assay, flow cytometric analysis, Transwell migration and invasion assays, and xenograft tumor model analysis were performed to assess the malignant biological behaviors of TSCC cells after NOP14-AS1 depletion. Mechanistic studies were performed using bioinformatics analysis, luciferase reporter assay, RNA immunoprecipitation, and rescue experiments.

Results

NOP14-AS1 upregulation was identified in TSCC tissues and cell lines. Patients with TSCC exhibiting a high NOP14-AS1 expression faced shorter overall survival than those with a low NOP14-AS1 expression. Functionally, NOP14-AS1 depletion facilitated apoptosis and impeded cell proliferation, migration, and invasion in TSCC. In vivo, the growth of TSCC cells was hindered by NOP14-AS1 depletion. Mechanically, NOP14-AS1 functioned as a competing endogenous RNA by sponging microRNA-665 (miR-665), thereby overexpressing the target high mobility group box 3 (HMGB3) of miR-665. Lastly, rescue experiments confirmed that the introduction of HMGB3 overexpression plasmid or miR-665 inhibitor could abrogate the inhibition of aggressive phenotypes triggered by NOP14-AS1 knockdown.

Conclusion

NOP14-AS1 executed pro-oncogenic activities in TSCC cells by targeting the miR-665/HMGB3 axis. The NOP14-AS1/miR-665/HMGB pathway may be a valuable prognostic indicator and therapeutic target for preventing TSCC.

Long Intergenic Non-Coding RNA LINC00885 Promotes Tumorigenesis of Cervical Cancer by Upregulating MACC1 Expression Through Serving as a Competitive Endogenous RNA for microRNA-432-5p

Purpose

Long intergenic non-protein coding RNA 885 (LINC00885) has been well studied in breast cancer; however, its contribution in cervical cancer remains unclear. In this study, we aimed to determine the detailed functions of LINC00885 in cervical cancer and elucidate the underlying molecular regulation mechanism.

Methods

The expression status of LINC00885 in cervical cancer was determined using reverse transcription-quantitative polymerase chain reaction and by searching The Cancer Genome Atlas database. The detailed functions of LINC00885 in cervical cancer cells were confirmed using Cell Counting Kit 8 assay, flow cytometry analysis, Transwell cell migration and invasion assays, and tumor xenograft assay. Mechanistic experiments included bioinformatics prediction, RNA immunoprecipitation, luciferase reporter assay, and rescue experiments.

Results

LINC00885 was clearly overexpressed in cervical cancer, which was linked with unfavorable clinical outcomes. Functionally, LINC00885 deficiency suppressed cervical cancer cell proliferation, migration, and invasion but stimulated cell apoptosis in vitro. Furthermore, loss of LINC00885 restricted the growth of cervical cancer cells in vivo. Mechanistically, LINC00885 functioned as a competitive endogenous RNA for microRNA-432-5p (miR-432-5p) in cervical cancer. Furthermore, metastasis-associated colon cancer 1 (MACC1) was confirmed as the direct target of miR-432-5p, and LINC00885 could enhance MACC1 expression by sequestering miR-432-5p. Rescue experiments revealed that silencing of miR-432-5p or upregulation of MACC1 expression could effectively counteract the restrained aggressive properties of cervical cancer cells induced by LINC00885 deficiency.

Conclusion

LINC00885 upregulated MACC1 expression in cervical cancer cells by sponging miR-432-5p, thereby promoting cancer progression. The LINC00885/miR-432-5p/MACC1 pathway may help in the identification of potential prognostic biomarkers and therapeutic targets in cervical cancer.

Long non‑coding RNA LINC01006 exhibits oncogenic properties in cervical cancer by functioning as a molecular sponge for microRNA‑28‑5p and increasing PAK2 expression

As previously reported, long intergenic non‑protein‑coding RNA 1006 (LINC01006) plays crucial roles in prostate, pancreatic and gastric cancers. However, whether it plays important roles in cervical cancer remains unclear. The present study thus aimed to determine the precise role of LINC01006 in cervical cancer and elucidate its regulatory mechanisms. The expression of LINC01006 in cervical cancer was examined by reverse transcription‑quantitative polymerase chain reaction. Cell proliferation assay, flow cytometric analysis, Transwell migration and invasion assays, and tumor xenograft model experiments were performed to elucidate the roles of LINC01006 in cervical cancer. Bioinformatics analysis, luciferase reporter assay, RNA immunoprecipitation and rescue experiments were performed for mechanistic analyses. The expression of LINC01006 was found to be upregulated in cervical cancer and to be associated with a poor prognosis. The absence of LINC01006 inhibited the proliferation, migration and invasion of cervical cancer cells, whereas it promoted cell apoptosis in vitro. The downregulation of LINC01006 impeded tumor growth in vivo. LINC01006 was verified as an endogenous 'sponge' that competed for microRNA‑28‑5p (miR‑28‑5p), which resulted in the upregulation of the miR‑28‑5p target P21‑activated kinase 2 (PAK2). Rescue experiments revealed that the suppression of miR‑28‑5p expression or the overexpression of PAK2 abrogated the effects of LINC01006 downregulation on malignant cellular functions in cervical cancer. On the whole, the present study demonstrates that LINC01006 exhibits tumor‑promoting functions in cervical cancer via the regulation of the miR‑28‑5p/PAK2 axis. These findings may provide the basis for the identification of LINC01006‑targeted clinical therapy.

Long non-coding RNA AK001903 regulates tumor progression in cervical cancer

A majority of cervical cancers are squamous cell carcinomas, arising from the squamous (flattened) epithelial cells that line the cervix. Long noncoding RNAs (lncRNAs) are a unique class of messenger RNA-like transcripts of at least 200 nucleotides in length with no significant protein-coding capacity. Aberrant lncRNA expression is emerging as a major component of the cancer transcriptome. In the present study, lncRNA microarrays were conducted to investigate the differentially expression lncRNAs in cervical cancer (CC) tissues compared with peritumoral tissues. Then, the most significantly upregulated lncRNA, which was lncRNA-AK001903 was selected to conduct further experiments. Real-time Quantitative polymerase chain reaction was conducted to investigate lncRNA-AK001903 expression in CC tissues and Hela, Siha, Ca Ski, C33a, H8 (HPV-immortalized cervical epithelial cell line) cell lines, and in situ hybridization histochemistry (ISHH) was performed to detect lncRNA-AK001903 expression level in different CC stages. The effect of lncRNA-AK001903 on cell proliferation, invasion and migration was assessed after knockdown of lncRNA-AK001903. The findings of the study confirmed that lncRNA-AK001903 was upregulated in CC cells and tissues compared with normal cell line H8 and peritumoral tissues. ISHH demonstrated that the expression level of lncRNA-AK001903 was connected with International Federation of Gynecology and Obstetrics (2018) stage of CC. Knockdown of lncRNA-AK001903 inhibited cell proliferation, invasion and migration in Ca Ski cells. In conclusion, lncRNA-AK001903 was demonstrated to be an oncogenic lncRNA that promotes tumor progression and may be an effective target for CC treatment in the near future.