RETRACTED: Reciprocal regulation of miR-1254 and c-Myc in oral squamous cell carcinoma suppresses EMT-mediated metastasis and tumor-initiating properties through MAPK signaling

MiR-1254 suppresses the proliferation and invasion of cervical cancer cells by modulating CD36

BACKGROUND

This study aimed to elucidate the roles of miR-1254 in cervical cancer progression and to explore the underlying mechanisms.

METHODS

The expression levels of miR-1254 in normal-cancer cervical tissues and cells were measured using quantitive real-time polymerase chain reaction (qRT-PCR). The invasive and proliferative abilities of cervical cancer cell lines transfected with negative control (NC) mimic or miR-1254 mimic were measured using transwell, CCK-8, and colony formation assays. The binding sites between CD36 and miR-1254 were determined using luciferase reporter assays. The correlation of CD36 and miR-1254 with cervical cancer development was re-confirmed by co-transfection of miR-1254 mimic and CD36 overexpression using CCK-8, colony formation, transwell and western blot assays.

RESULTS

MiR-1254 was expressed at significantly lower levels in the cervical cancer cell lines and tissues than in the controls. The functional assays revealed that upregulation of miR-1254 inhibited the invasion and proliferation of cervical cancer cells. The luciferase reporter assays demonstrated that CD36 messenger RNA and miR-1254 bound to one another. CD36 overexpression reversed the inhibitory effects of upregulated miR-1254 in the cervical cancer cells, suggesting that miR-1254 regulates cervical cancer progression by modulating CD36.

CONCLUSION

miR-1254 attenuated the invasion and proliferation of cervical cancer cells by modulating the expression levels of CD36.

Activating IL-6/STAT3 Enhances Protein Stability of Proteasome 20S α+β in Colorectal Cancer by miR-1254

A widely recognized feature of colorectal cancer (CRC) is an increase in cytokine levels, which result in an inflammatory environment in the tumor. Interleukin-6 (IL-6) is a robust protumor cytokine. Several studies suggest that IL-6 plays a role in the development of tumors. Most intracellular protein breakdown occurs in eukaryotes via the ubiquitin-proteasome pathway; this mechanism may also be involved in cancer pathogenesis. The tumor tissues and paracancerous tissues were collected from 90 patients with colorectal cancer. The expressions of pSTAT3, proteasome 20S α+β, miR-1254, and PSMD1 in tissues were detected by immunohistochemistry, ELISA, and qRT-PCR, and the effects of pSTAT3 and proteasome 20s α+β expressions on the survival of patients were studied. HCT116 and HCT116-R cells were cultured and added IL-6, AG490, STAT3 plasmid, or overexpression/knockdown of miR-1254 in cells. Immunofluorescence, western blot, qRT-PCR, double luciferase gene reporter assay, and flow cytometry were used to detect the expression of pSTAT3, STAT3, proteasome 20s α+β, miR-1254, and PSMD1 and cell cycle. The nude mouse xenograft model was constructed and divided into 3 groups: PBS group, IL-6 treatment group, and IL-6+miR-1254 mimic group. After 28 days, the tumor tissues were collected, and the expressions of miR-1254, pSTST3, proteasome 20s α+β, and PSMD1 in the tissues were detected by qRT-PCR and immunohistochemistry, respectively. Our study discovered that the level of proteasome 20S α+β had a strong connection with pSTAT3 in CRC patients. They were also linked to the development and clinical outcome of CRC. In addition, we found that IL-6 dramatically increased the expression of proteasome 20S α+β and pSTAT3; however, it did not affect the proteasome 20S α+β mRNA synthesis. Circulating proteasome concentration correlated with tumor tissue proteasome 20S α+β. STAT3 could occupy the miR-1254 promoter to inhibit transcription, and it could suppressed miR-1254 which targeted PSMD10, promoting proteasome 20S α+β protein stability. This is a prospective target for developing a new colorectal cancer therapy strategy.

BAP18 is involved in upregulation of CCND1/2 transcription to promote cell growth in oral squamous cell carcinoma

BACKGROUND

As a reader of histone H3K4me3, BPTF associated protein of 18 kDa (BAP18) is involved in modulation of androgen receptor action in prostate cancer. However, the function of BAP18 on oral squamous cell carcinoma (OSCC) and its molecular mechanism remains to be elusive.

METHODS

OSCC-derived cell lines carrying silenced BAP18 were established by Lentiviral infection. Quantitative PCR (qPCR), western blot, and ChIP assay were performed to detect gene transcription regulation and the possible mechanism. Colony formation, cell growth curve and xenograft tumor experiments were performed to examine cell growth and proliferation.

FINDINGS

Our study demonstrated that BAP18 was highly expressed in OSCC samples compared with that in benign. BAP18 depletion obviously influenced the expression of a series of genes, including cell cycle-related genes. We thus provided the evidence to demonstrate that BAP18 depletion significantly decreases CCND1 and CCND2 (CCND1/2) transcription. In addition, BAP18 is recruited to the promoter regions of CCND1/2, thereby facilitating the recruitment of the core subunits of MLL1 complex to the same regions, to increase histone H3K4me3 levels. Furthermore, BAP18 depletion delayed G1-S phase transition and inhibited cell growth in OSCC-derived cell lines.

INTERPRETATION

This study suggests that BAP18 is involved in modulation of CCND1/2 transcription and promotes OSCC progression. BAP18 could be a potential target for OSCC treatment and diagnosis. FUND: This work was funded by National Natural Science Foundation of China (31871286, 81872015, 31701102, 81702800, 81902889), Foundation for Special Professor of Liaoning Province, and Supported project for young technological innovation-talents in Shenyang (No. RC170541).

Knocking down of LINC01220 inhibits proliferation and induces apoptosis of endometrial carcinoma through silencing MAPK11

Background: Endometrial carcinoma (EC) still threatens the health of women. Thus, to explore how long intergenic non-protein coding RNA 01220 regulates the development of EC.

Methods: Whole genome expression profile data of EC and paracancerous tissues in TCGA database were downloaded. LINC01220 expression in EC and paracancerous tissues of patients in our hospital were detected by qRT-PCR. Furthermore, the relationship between LINC01220 expression and clinicopathological features of EC patients was analyzed. After transfection with sh-LINC01220 and pcDNA-MAPK11 (mitogen-activated protein kinase) in EC cells, proliferative, colony formation abilities and apoptosis were determined by cell counting kit-8 (CCK-8), colony formation assay and flow cytometry, respectively. Western blot was conducted to determine the regulatory role of LINC01220 on MAPK11.

Results: TCGA data showed that LINC01220 expression is markedly higher in EC tissues than that of paracancerous tissues, which was consistent without detection in EC patients of our hospital. LINC01220 expression was positively correlated to pathological grade and International Federation of Gynecology and Obstetrics (FIGO) stage of EC patients. After knockdown of LINC01220 in EC cells, proliferative and colony formation abilities decreased, whereas apoptotic rate increased. Cor function analysis revealed the positive correlation between LINC01220 and MAPK11 in EC. MAPK11 expression was regulated by LINC01220 in EC cells. Overexpression of MAPK11 can reverse the tumor suppressing effect of LINC01220 on EC.

Conclusions: LINC01220 promotes EC development by stimulating proliferation and inhibiting apoptosis of EC cells through up-regulating MAPK11.

POM121 is identified as a novel prognostic marker of oral squamous cell carcinoma

Background: The aim of this study was to confirm the role of nuclear pore membrane protein 121(POM121) in oral squamous cell carcinoma and to explore the underlying mechanism. Methods: POM121mRNA and protein expressions were evaluated in OSCC tissues and normal oral tissues by quantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemistry. The relationship between POM121 expression and clinical characteristics was analyzed. Bioinformatics analysis was performed to explore the possible mechanisms how POM121 affected OSCC. Results: We confirmed that POM121 mRNA expression in OSCC tissues was significantly higher than that in non-tumorous tissues, as was POM121 protein expression. POM121 expression was associated with distant metastasis and TNM stage. Multivariate analysis confirmed POM121 expression as an independent prognostic factor for OSCC patients. OSCC patients with high POM121 expression had a worse overall survival (OS) compared with patients with low POM121 expression. Bioinformatics analysis indicated POM121 may regulate OSCC through hedgehog and /or p53 signaling pathway. Conclusion: Targeting of POM121 expression levels could provide new diagnostic and therapeutic strategies for OSCC patients.

MicroRNA-1254 exerts oncogenic effects by directly targeting RASSF9 in human breast cancer

MicroRNAs (miRNAs or miRs) play crucial roles in human breast cancer. Although miR-1254 has been shown to have oncogenic activity in several cancer types, its biological function in breast cancer and its mechanisms of action remain unclear. In this study, we investigated the role of miR-1254 in human breast cancer and sought to elucidate the relevant underlying mechanisms. We found that miR-1254 expression was markedly increased in breast cancer tissues and cell lines. Additionally, miR-1254 overexpression accelerated breast cancer cell proliferation, cell cycle G1-S phase transition and inhibited apoptosis. Nevertheless, the inhibition of miR-1254 suppressed cell proliferation and induced apoptosis. Further analyses revealed that miR-1254 expression negatively correlated with RASSF9 expression in breast cancer tissues. We verified that RASSF9 was a direct target of miR-1254 using a luciferase reporter assay. The overexpression of miR-1254 reduced the RASSF9 mRNA and protein levels, and the suppression of miR-1254 promoted RASSF9 expression. Notably, the knockdown or overexpression of RASSF9 corroborated the biological effects observed upon miR-1254 overexpression or inhibition. Taken together, these results demonstrate that miR-1254 accelerates breast cancer cell growth by activating the AKT signaling pathway and suppresses apoptosis by inhibiting p53 expression through the targeting of RASSF9. The data indicate that miR-1254 plays a crucial role in human breast cancer, and may represent a novel therapeutic target for this malignancy.

Predictive Prognostic Value of Tissue-Based MicroRNA Expression in Oral Squamous Cell Carcinoma: A Systematic Review and Meta-analysis

Oral squamous cell carcinoma (OSCC) is a common type of cancer characterized by a low survival rate, mostly due to local recurrence and metastasis. In view of the importance of predicting tumor behavior in the choice of treatment strategies for OSCC, several studies have attempted to investigate the prognostic value of tissue biomarkers, including microRNA (miRNA). The purpose of this study was to perform a systematic review and meta-analysis to evaluate the relationship between miRNA expression and survival of OSCC patients. Studies were identified by searching on MEDLINE/PubMed, SCOPUS, Web of Science, and Google Scholar. Quality assessment of studies was performed with the Newcastle-Ottawa Scale. Data were collected from cohort studies comparing disease-free survival and overall survival in patients with high miRNA expression compared to those with low expression. A total of 15 studies featuring 1,200 OSCC samples, predominantly from Asia, met the inclusion criteria and were included in the meta-analysis. Poor prognosis correlated with upregulation of 9 miRNAs (miR-21, miR-455-5p, miiR-155-5p, miR-372, miR-373, miR-29b, miR-1246, miR-196a, and miR-181) and downregulation of 7 miRNAs (miR-204, miR-101, miR-32, miR-20a, miR-16, miR-17, and miR-125b). The pooled hazard ratio values (95% confidence interval) related to different miRNA expression for overall survival and disease-free survival were 2.65 (2.07–3.39) and 1.95 (1.28–2.98), respectively. The results of this meta-analysis revealed that the expression levels of specific miRNAs can robustly predict prognosis of OSCC patients.

C-MYC and BCL-2 mediate YAP-regulated tumorigenesis in OSCC

Transcriptional co-activator Yes-associated protein (YAP) is a key oncogene in mammalian cells. The present understanding of YAP in oral squamous cells carcinoma (OSCC) remains unclear. The purpose of this study is to investigate the effects of YAP on proliferation and apoptosis in OSCC and the molecular mechanism. The results showed the expression level of YAP was higher in OSCC tissues than that in adjacent normal tissues. Knockdown of YAP in CAL27 cell lines prohibited cell proliferation while augmented apoptosis. Conversely, overexpression of YAP protected cells from apoptosis and promoted cell proliferation. Moreover, C-MYC and BCL-2 mRNA and protein levels were altered due to the differential expression of YAP. Subsequent Verteporfin treatment in CAL27 cells revealed that the transcription and translation of BCL-2 and C-MYC both decreased. In a tumor xenograft model, knockdown of YAP suppressed tumor growth of CAL27 in vivo, while YAP overexpression promoted the tumor growth. These results suggest that YAP is a crucial regulator that exerts pro-proliferation and anti-apoptosis effects in OSCC through actions affecting the cell cycle and intrinsic apoptotic signaling. Thus YAP could potentially serve as a valuable molecular biomarker or therapeutic target in the treatment of OSCC.

Inhibition of EGF-induced migration and invasion by sulfated polysaccharide of Sepiella maindroni ink via the suppression of EGFR/Akt/p38 MAPK/MMP-2 signaling pathway in KB cells

SIP-SII, the sulfated Sepiella maindroni ink polysaccharide (SIP), has been manifested to possess anti-tumor and anti-metastasis activity in vivo and in vitro. In the present study, we evaluated its inhibitory effect on the epidermal growth factor (EGF)-induced migration and invasion of human epidermoid carcinoma cell (KB cell line) as well as the related signaling pathways. The results of MTT assay indicated that SIP-SII inhibited the proliferation of KB cells in a concentration and time dependent manner. Notably, the attenuation of cell growth by SIP-SII was enlarged in the presence of EGF. The wound healing assay and transwell invasion assay were used to evaluate the effect of SIP-SII on the EGF-induced migration and invasion of KB cells and the results showed that SIP-SII markedly attenuated the EGF-induced migration and invasion. Besides, the EGF-induced matrix metalloproteinase-2 (MMP-2) expression was also suppressed by SIP-SII. However, SIP-SII showed no significant inhibition of the EGF-induced matrix metalloproteinase-9 (MMP-9) expression. Further research revealed that SIP-SII decreased the EGF-induced phosphorylation of epidermal growth factor receptor (EGFR), Akt and p38, but no significant suppression on EGF-induced phosphorylation of extracellular signal-regulated kinase 1 and 2 (Erk1/2) and c-Jun N-terminal kinases (JNK) by SIP-SII treatment was observed. The involvement of EGFR/Akt/p38 pathway was confirmed by evidence that SIP-SII would enlarge the inhibitory effect of the specific signal pathway inhibitors. These results indicate that SIP-SII has the potential to be used as the inhibitor of tumor metastasis especially for cancers characterized by over-activation of EGF/EGFR signaling.

miR-1254 promotes lung cancer cell proliferation by targeting SFRP1

Lung cancer is the leading cause of cancer deaths worldwide, many miRNAs play critical role in lung cancer initiation and progression. Here, we demonstrated that miR-1254 was upregulated in lung cancer tissues and cells. miR-1254 overexpression promoted lung cancer cell proliferation determined by MTT assay, colony formation assay, soft agar growth ability assay and BrdU incorporation assay, miR-1254 knockdown suppressed lung cancer cell proliferation. Mechanism analysis revealed that Wnt/β-catenin pathway antagonist secreted frizzled related protein 1 (SFRP1) was its target, its expression was opposite to SFRP1 level, and directly bound to the 3'UTR of SFRP1. Double knockdown of miR-1254 and SFRP1 promoted lung cancer cell proliferation, suggesting miR-1254 promoted lung cancer cell proliferation by targeting SFRP1.