A patient-derived organoid-based study identified an ASO targeting SNORD14E for endometrial cancer through reducing aberrant FOXM1 Expression and ß-catenin nuclear accumulation.

BACKGROUND: Most of the endometrial cancer (EC) patients are diagnosis in early stage with a good prognosis while the patients with locally advanced recurrent or metastatic result in a poor prognosis. Adjuvant therapy could benefit the prognosis of patients with high-risk factors. Unfortunately, the molecular classification of great prognostic value has not yet reached an agreement and need to be further refined. The present study aims to identify new targets that have prognostic value in EC based on the method of EC patient-derived organ-like organs (PDOs), and further investigate their efficacy and mechanism. METHODS: The Cancer Genome Atlas (TCGA) database was used to determine SNORD14E expression. The effects of SNORD14E were investigated using CCK8, Transwell, wound-healing assays, and a xenograft model experiment; apoptosis was measured by flow cytometry. Antisense oligonucleotide (ASO) targeting SNORD14E was designed and patient-derived organoids (PDO) models in EC patients was established. A xenograft mouse and PDO model were employed to evaluate the effects of ASO targeting SNORD14E. RNA-seq, Nm-seq, and RNA immunoprecipitation (RIP) experiments were employed to confirm the alternative splicing (AS) and modification induced by SNORD14E. A minigene reporter gene assay was conducted to confirm AS and splicing factors on a variable exon. Actinomycin-d (Act-D) and Reverse Transcription at Low deoxy-ribonucleoside triphosphate concentrations followed by PCR (RTL-P) were utilized to confirm the effects of 2'-O methylation modification on FOXM1. RESULTS: We found that SNORD14E was overexpressed in EC tissues and patients with high expressed SNORD14E were distributed in the TCGA biomolecular classification subgroups without difference. Further, SNORD14E could reduce disease-free survival (DFS) and recurrence free survival (RFS) of EC patients. SNORD14E promoted proliferation, migration, and invasion and inhibited the apoptosis of EC cells in vitro. ASOs targeting SNORD14E inhibited cell proliferation, migration, invasion while promoted cell apoptosis. ASOs targeting SNORD14E inhibited tumor growth in the xenograft mouse model. TCGA-UCEC database showed that the proportion of patients with high expression of SNORD14E in middle-high risk and high-risk patients recommended by EMSO-ESGO-ESTRO guidelines for adjuvant therapy is more than 50%. Next, we enrolled 8 cases of high-risk and high-risk EC patients according to EMSO-ESGO-ESTRO guidelines and successfully constructed EC-PDOs. ASOs targeting SNORD14E inhibited the EC-PDO growth. Mechanistically, SNORD14E could recognize the mRNA of FOXM1 and recruit SRSF1 to promote the shearing of the variable exon VIIa of FOXM1, resulting in the overexpression of the FOXM1 malignant subtypes FOXM1b and FOXM1c. In addition, SNORD14E modified FOXM1 mRNA with 2`-O-methylation, which prolonged the half-life of FOXM1 mRNA. The nucleus accumulation of ß-catenin caused by aberrant FOXM1 expression led to EC progression. CONCLUSIONS: ASO targeting SNORD14E can be an effective treatment for EC.

SNORD60 promotes the tumorigenesis and progression of endometrial cancer through binding PIK3CA and regulating PI3K/AKT/mTOR signaling pathway.

Endometrial carcinoma is a common gynecological malignant tumor, small nucleolar RNAs (snoRNAs) are involved in cancer development. However, researches on the roles of snoRNAs in endometrial carcinoma are limited. The expression levels of snoRNAs in endometrial cancer tissues were analyzed using The Cancer Genome Atlas (TCGA) database. Antisense oligonucleotides (ASOs) and plasmids were used for transfection. Moreover, CCK-8, EdU, wound-healing assay, transwell, cell apoptosis, western blotting, and xenograft model were employed to examine the biological functions of related molecules. real-time reverse transcription polymerase chain reaction and western blotting were performed to detect messenger RNA (mRNA) and protein levels. Including bioinformatics, fluorescence in situ hybridization, RNA pulldown, actinomycin D and RTL-P assays were also carried out to explore the molecular mechanism. Analysis of data from TCGA showed that the expression level of small nucleolar RNA, C/D box 60 (SNORD60) in endometrial cancer tissues is observably higher than that in normal endometrial tissues. Further research suggested that SNORD60 played a carcinogenic role both in vitro and in vivo, and significantly upregulated the expression of PIK3CA. However, the carcinogenic effects can be reversed by knocking down fibrillarin (FBL) or PIK3CA. SNORD60 forms complexes by binding with 2'-O-methyltransferase fibrillarin, thus catalyzes the 2'-O-methylation (Nm) modification of PIK3CA mRNA and modulates the PI3K/AKT/mTOR signaling pathway, so as to promote the development of endometrial cancer. In short, SNORD60 might become a new biomarker for the therapy of endometrial cancer in the future and provide new strategies for diagnosis and treatment.

SNORA70E promotes the occurrence and development of ovarian cancer through pseudouridylation modification of RAP1B and alternative splicing of PARPBP.

The present study demonstrated for the first time that SNORA70E, which belongs to box H/ACA small nucleolar noncoding RNAs (snoRNAs) who could bind and induce pseudouridylation of RNAs, was significantly elevated in ovarian cancer tissues and was an unfavourable prognostic factor of ovarian cancer. The over-expression of SNORA70E showed increased cell proliferation, invasion and migration in vitro and induced tumour growth in vivo. Further research found that SNORA70E regulates RAS-Related Protein 1B (RAP1B) mRNA through pseudouracil modification by combing with the pyrimidine synthase Dyskerin Pseudouridine Synthase 1 (DKC1) and increase RAP1B protein level. What's more, the silencing of DKC1/RAP1B in SNORA70E overexpression cells both inhibited cell proliferation, migration and invasion through reducing ß-catenin, PI3K, AKT1, mTOR, and MMP9 protein levels. Besides, RNA-Seq results revealed that SNORA70E regulates the alternative splicing of PARP-1 binding protein (PARPBP), leading to the 4th exon-skipping in PARPBP-88, forming a new transcript PARPBP-15, which promoted cell invasion, migration and proliferation. Finally, ASO-mediated silencing of SNORA70E could inhibit ovarian cancer cell proliferation, invasion, migration ability in vitro and inhibit tumorigenicity in vivo. In conclusion, SNORA70E promotes the occurrence and development of ovarian cancer through pseudouridylation modification of RAP1B and alternative splicing of PARPBP. Our results demonstrated that SNORA70E may be a new diagnostic and therapeutic target for ovarian cancer.

snoRNAs: functions and mechanisms in biological processes, and roles in tumor pathophysiology.

Small nucleolar RNAs (snoRNAs), a type of non-coding RNA, are widely present in the nucleoli of eukaryotic cells and play an important role in rRNA modification. With the recent increase in research on snoRNAs, new evidence has emerged indicating that snoRNAs also participate in tRNA and mRNA modification. Studies suggest that numerous snoRNAs, including tumor-promoting and tumor-suppressing snoRNAs, are not only dysregulated in tumors but also show associations with clinical prognosis. In this review, we summarize the reported functions of snoRNAs and the possible mechanisms underlying their role in tumorigenesis and cancer development to guide the snoRNA-based clinical diagnosis and treatment of cancer in the future.

The function and regulation mechanism of piRNAs in human cancers.

Piwi-interacting RNAs (piRNAs) are mainly expressed in mammalian germ cells, playing an important role in maintaining germ line DNA integrity, inhibiting transposon transcription and translation, participating in heterochromatin formation, epigenetic regulation, and germ cell genesis. They combine with P-element induced wimpy testis (PIWI) proteins to form effector complexes known as piRNA-induced silencing complexes (pi-RISC) to regulate the gene silencing pathway. Recent evidence suggests that numerous piRNAs, with tumor-promoting and tumor-suppressing functions in cancer development, are dysregulated in tumor tissues, and are related to clinical prognosis. In the present review, we summarize the current state of knowledge on the function and regulatory mechanisms of piRNAs in the tumorigenesis and progression of cancer, providing evidence for the potential use of piRNAs in the diagnosis and clinical treatment of cancer.

Diagnostic accuracy of sonography versus magnetic resonance imaging for primary nasopharyngeal carcinoma.

OBJECTIVES: The purpose of this study was to prospectively assess the accuracy of sonography versus magnetic resonance imaging (MRI) for a diagnosis of primary nasopharyngeal carcinoma. METHODS: A total of 150 patients suspected of having nasopharyngeal carcinoma underwent sonography and MRI. A diagnosis was obtained from an endoscopic biopsy that was collected from the suspected tumor or a normal nasopharynx. The diagnostic performance of sonography and MRI for nasopharyngeal carcinoma was evaluated by receiver operating characteristic curve analysis. The sensitivity and specificity of the two imaging methods were compared by the McNemar test. RESULTS: Nasopharyngeal carcinoma was present in 71 of 150 patients (47.3%) and absent in 79 (52.7%). The sensitivity, specificity, and accuracy of sonography versus MRI for these cases were 90.1%, 84.8%, and 87.3% for sonography and 97.2%, 89.9%, and 93.3% for MRI, respectively. Both sonography and MRI had good diagnostic performance for nasopharyngeal carcinoma, with area under the curve values of 0.958 and 0.987, respectively. There was no significant difference in the rate of tumor detectability between sonography and MRI (P = .12), and the specificities of sonography and MRI were similar (P = .22). CONCLUSIONS: Both sonography and MRI are useful tools for clinical screening of nasopharyngeal carcinoma. However, sonography is less expensive and easier to perform. The results of this study also suggest that nasopharyngeal sonography could be used for the initial investigation of primary cancer in patients suspected of having nasopharyngeal carcinoma.