Correlations between Overexpression of SOX2OT Long Non-coding RNA and Susceptibility to Breast Cancer

Long non-coding RNA SOX2OT in tamoxifen-resistant breast cancer

Hormone receptor (HR)-positive breast cancer can become aggressive after developing hormone-treatment resistance. This study elucidated the role of long non-coding RNA (lncRNA) SOX2OT in tamoxifen-resistant (TAMR) breast cancer and its potential interplay with the tumor microenvironment (TME). TAMR breast cancer cell lines TAMR-V and TAMR-H were compared with the luminal type A cell line (MCF-7). LncRNA expression was assessed via next-generation sequencing, RNA extraction, lncRNA profiling, and quantitative RT-qPCR. SOX2OT overexpression effects on cell proliferation, migration, and invasion were evaluated using various assays. SOX2OT was consistently downregulated in TAMR cell lines and TAMR breast cancer tissue. Overexpression of SOX2OT in TAMR cells increased cell proliferation and cell invasion. However, SOX2OT overexpression did not significantly alter SOX2 levels, suggesting an independent interaction within TAMR cells. Kaplan-Meier plot analysis revealed an inverse relationship between SOX2OT expression and prognosis in luminal A and B breast cancers. Our findings highlight the potential role of SOX2OT in TAMR breast cancer progression. The downregulation of SOX2OT in TAMR breast cancer indicates its involvement in resistance mechanisms. Further studies should explore the intricate interactions between SOX2OT, SOX2, and TME in breast cancer subtypes.

LINC00704 contributes to the proliferation and accelerates the cell cycle of nasopharyngeal carcinoma cells via regulating ETS1/CDK6 axis

This study is aimed at exploring the biological functions and related mechanism of long noncoding RNA 704 (LINC00704) in the proliferation and cell cycle progression of nasopharyngeal carcinoma (NPC) cells. The expression of LINC00704 in NPC tissues and cells was quantified by quantitative real-time polymerase chain reaction (qRT-PCR). After LINC00704 was overexpressed or knocked down in NPC cell lines, cell counting kit-8 (CCK-8) assay, 5-bromo-2'-deoxyuridine assay, flow cytometry assay, and Transwell assay were adopted to detect the proliferation, cell cycle progression, migration, and invasion of NPC cells. The interaction between LINC00704 and ETS proto-oncogene 1 (ETS1) was verified by bioinformatics analysis, RNA pull-down assay, and RNA immunoprecipitation assay. Dual-luciferase reporter gene assay and chromatin immunoprecipitation followed by qPCR analysis were used to verify the binding status between ETS1 and the promoter region of cyclin-dependent kinase 6 (CDK6). The regulatory effects of LINC00704 and ETS1 on CDK6 expression were detected by Western blot. LINC00704 expression was elevated in NPC tissues and cells, which was significantly correlated with the advanced TNM stage and poor differentiation. LINC00704 overexpression promoted the multiplication, migration, and invasion of NPC cells and blocked the cell cycle progression while knocking down LINC00704 worked oppositely. LINC00704 could bind to ETS1, thus promoting CDK6 transcription. Knocking down LINC00704 inhibited the CDK6 expression in NPC cells. LINC00704 promotes CDK6 transcription by recruiting ETS1 to the promoter region of CDK6, thus promoting the malignant progression of NPC.

A novel lncRNA SOX2OT promotes the malignancy of human colorectal cancer by interacting with miR-194-5p/SOX5 axis

Long noncoding RNAs (lncRNAs) show emerging roles in colorectal cancer (CRC) development and are considered to be involved in the potential mechanism of tumor malignancy. While Sox2 overlapping transcript (SOX2OT) has been implicated in the progression of multiple cancers, its role in CRC remains to be explored. In this study, in situ hybridization (ISH) and qRT-PCR were performed to establish the functional relationships between SOX2OT and CRC deranged in CRC tissue and cells. Subsequently, SOX2OT shRNAs vectors were transfected into CRC cells to performed loss-of-function assays to detect the potential role of SOX2OT on proliferation and metastasis in vitro and vivo. The results showed SOX2OT was an oncogene that was up-regulated in human CRC tissues and cell lines. SOX2OT silencing suppressed cell proliferation, migration, and invasion in CRC cells in vitro, and inhibited tumorigenesis in the mouse xenografts. Bioinformatic predictive analysis coupled with the dual-luciferase reporter, RNA immunoprecipitation (RIP), and functional rescue assay elucidated the mechanistic network of the SOX2OT-miR-194-5p-SOX5 axis in CRC. Mechanistically, SOX2OT acted as a competing endogenous RNA (ceRNA) to upregulate SOX5 by sponging miR-194-5p. Downregulated SOX2OT boosted miR-194-5p expression, thus decreased the protein level of SOX5, which suppresses tumorgenesis of CRC.

LncRNA SOX2OT rs9839776 Polymorphism Reduces Sepsis Susceptibility in Southern Chinese Children

Background

Sepsis in children is one of the main causes of death in pediatric intensive care units (PICUs); however, the pathogenesis of sepsis is not fully clear. Previous studies revealed that many genetic variations were related to sepsis susceptibility. A long non-coding RNA SOX2 overlapping transcript (SOX2OT) may play a role in mitochondrial homeostasis and antioxidative activity, but the relationship between the lncRNA SOX2OT polymorphism and sepsis susceptibility has not been reported.

Methods

In this study, 474 pediatric sepsis patients and 678 healthy controls were recruited from southern China. After genotyping, the strength of the associations was evaluated through odds ratios (ORs) and 95% confidence intervals (CIs).

Results

The SOX2OT rs9839776 T allele was associated with decreased susceptibility to sepsis in southern Chinese children (TT/CT vs CC adjusted OR = 0.778, 95% CI = 0.610–0.992; P = 0.0431). Moreover, the difference in susceptibility was greater in children of age >60 months (adjusted OR = 0.458, 95% CI = 0.234–0.896; P = 0.0225), survivors (adjusted OR = 0.758, 95% CI = 0.585–0.972; P = 0.0358), males (adjusted OR = 0.655, 95% CI = 0.479–0.894; P = 0.0077) and the sepsis subgroup (adjusted OR = 0.548, 95% CI = 0.343–0.876; P = 0.0120).

Conclusion

The rs9839776 T allele may contribute to decreased sepsis risk in Chinese children. Future studies with a larger sample size are needed to verify these results.