MicroRNA-3200-5p Promotes Osteosarcoma Cell Invasion via Suppression of BRMS1

Single-cell and spatial transcriptomics reveal metastasis mechanism and microenvironment remodeling of lymph node in osteosarcoma

BACKGROUND

Osteosarcoma (OS) is the most common primary malignant bone tumor and is highly prone to metastasis. OS can metastasize to the lymph node (LN) through the lymphatics, and the metastasis of tumor cells reestablishes the immune landscape of the LN, which is conducive to the growth of tumor cells. However, the mechanism of LN metastasis of osteosarcoma and remodeling of the metastatic lymph node (MLN) microenvironment is not clear.

METHODS

Single-cell RNA sequencing of 18 samples from paracancerous, primary tumor, and lymph nodes was performed. Then, new signaling axes closely related to metastasis were identified using bioinformatics, in vitro experiments, and immunohistochemistry. The mechanism of remodeling of the LN microenvironment in tumor cells was investigated by integrating single-cell and spatial transcriptomics.

RESULTS

From 18 single-cell sequencing samples, we obtained 117,964 cells. The pseudotime analysis revealed that osteoblast(OB) cells may follow a differentiation path from paracancerous tissue (PC) → primary tumor (PT) → MLN or from PC → PT, during the process of LN metastasis. Next, in combination of bioinformatics, in vitro and in vivo experiments, and immunohistochemistry, we determined that ETS2/IBSP, a new signal axis, might promote LN metastasis. Finally, single-cell and spatial dissection uncovered that OS cells could reshape the microenvironment of LN by interacting with various cell components, such as myeloid, cancer-associated fibroblasts (CAFs), and NK/T cells.

CONCLUSIONS

Collectively, our research revealed a new molecular mechanism of LN metastasis and clarified how OS cells influenced the LN microenvironment, which might provide new insight for blocking LN metastasis.

lncRNA RUNDC3A-AS1 Regulates Proliferation and Apoptosis of Thyroid Cancer Cells via the miR-151b/SNRPB Axis

The number of thyroid cancer (THCA) cases has increased dramatically worldwide. Many previous reports have confirmed that lncRNA is involved in the pathogenesis of THCA. However, the role and mechanism of lncRNA RUNDC3A-AS1 in THCA have not been studied. We intended to explore the effect of RUNDC3A-AS1 on the proliferation and apoptosis of THCA cells. Relative expression levels of RUNDC3A-AS1, microRNA (miR)-151b, and small nuclear ribonucleoprotein polypeptides B and B1 (SNRPB) were examined by reverse transcription quantitative polymerase chain reaction (RT-qPCR) in THCA cells. The localization of RUNDC3A-AS1 in THCA cells was detected by subcellular fractionation assay. The cell proliferation was tested by 5-ethynyl-2'-deoxyuridine (EdU), cell counting kit-8 (CCK-8), and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Flow cytometry was used to examine the cell apoptosis capacity. The relationships between RUNDC3A-AS1 and miR-151b or miR-151b and SNRPB were verified by luciferase reporter assay. The protein level was detected by Western blot analysis. RUNDC3A-AS1 exhibited high expression in THCA cells. RUNDC3A-AS1 knockdown suppressed cell proliferation but induced cell apoptosis. Importantly, RUNDC3A-AS1 targeted miR-151b to regulate the SNRPB expression. In rescue assays, SNRPB overexpression partially reversed the suppressive effect of RUNDC3A-AS1 knockdown on cell proliferation and the promotive effect of RUNDC3A-AS1 knockdown on cell apoptosis. The RUNDC3A-AS1/miR-151b/SNRPB axis regulated THCA cell proliferation and apoptosis, which provides novel insight into THCA investigation at the molecular level.

Regulation of breast cancer metastasis signaling by miRNAs

Despite the decline in death rate from breast cancer and recent advances in targeted therapies and combinations for the treatment of metastatic disease, metastatic breast cancer remains the second leading cause of cancer-associated death in U.S. women. The invasion-metastasis cascade involves a number of steps and multitudes of proteins and signaling molecules. The pathways include invasion, intravasation, circulation, extravasation, infiltration into a distant site to form a metastatic niche, and micrometastasis formation in a new environment. Each of these processes is regulated by changes in gene expression. Noncoding RNAs including microRNAs (miRNAs) are involved in breast cancer tumorigenesis, progression, and metastasis by post-transcriptional regulation of target gene expression. miRNAs can stimulate oncogenesis (oncomiRs), inhibit tumor growth (tumor suppressors or miRsupps), and regulate gene targets in metastasis (metastamiRs). The goal of this review is to summarize some of the key miRNAs that regulate genes and pathways involved in metastatic breast cancer with an emphasis on estrogen receptor α (ERα+) breast cancer. We reviewed the identity, regulation, human breast tumor expression, and reported prognostic significance of miRNAs that have been documented to directly target key genes in pathways, including epithelial-to-mesenchymal transition (EMT) contributing to the metastatic cascade. We critically evaluated the evidence for metastamiRs and their targets and miRNA regulation of metastasis suppressor genes in breast cancer progression and metastasis. It is clear that our understanding of miRNA regulation of targets in metastasis is incomplete.

BRMS1: a multifunctional signaling molecule in metastasis

Despite high mortality rates, molecular understanding of metastasis remains limited. It can be regulated by both pro- and anti-metastasis genes. The metastasis suppressor, breast cancer metastasis suppressor 1 (BRMS1), has been positively correlated with patient outcomes, but molecular functions are still being characterized. BRMS1 has been implicated in focal adhesion kinase (FAK), epidermal growth factor receptor (EGFR), and NF-κB signaling pathways. We review evidence that BRMS1 regulates these vast signaling pathways through chromatin remodeling as a member of mSin3 histone deacetylase complexes.

Identifying the Potential Differentially Expressed miRNAs and mRNAs in Osteonecrosis of the Femoral Head Based on Integrated Analysis

Purpose

Osteonecrosis of the femoral head is a common disease of the hip that leads to severe pain or joint disability. We aimed to identify potential differentially expressed miRNAs and mRNAs in osteonecrosis of the femoral head.

Methods

The data of miRNA and mRNA were firstly downloaded from the database. Secondly, the regulatory network of miRNAs-mRNAs was constructed, followed by function annotation of mRNAs. Thirdly, an in vitro experiment was applied to validate the expression of miRNAs and targeted mRNAs. Finally, GSE123568 dataset was used for electronic validation and diagnostic analysis of targeted mRNAs.

Results

Several regulatory interaction pairs between miRNA and mRNAs were identified, such as hsa-miR-378c-WNT3A/DACT1/CSF1, hsa-let-7a-5p-RCAN2/IL9R, hsa-miR-28-5p-RELA, hsa-miR-3200-5p-RELN, and hsa-miR-532-5p-CLDN18/CLDN10. Interestingly, CLDN10, CLDN18, CSF1, DACT1, IL9R, RCAN2, RELN, and WNT3A had the diagnostic value for osteonecrosis of the femoral head. Wnt signaling pathway (involved WNT3A), chemokine signaling pathway (involved RELA), focal adhesion and ECM-receptor interaction (involved RELN), cell adhesion molecules (CAMs) (involved CLDN18 and CLDN10), cytokine-cytokine receptor interaction, and hematopoietic cell lineage (involved CSF1 and IL9R) were identified.

Conclusion

The identified differentially expressed miRNAs and mRNAs may be involved in the pathology of osteonecrosis of the femoral head.

Deciphering of Key Pharmacological Pathways of Poria Cocos Intervention in Breast Cancer Based on Integrated Pharmacological Method

OBJECTIVE

Poria cocos (Fuling), a natural plant, has recently emerged as a promising strategy for cancer treatment. However, the molecular mechanisms of Poria cocos action in breast cancer remain poorly understood.

METHODS

TCMSP database was used to screen the potential active ingredients in Poria cocos. GEO database was used to identify differentially expressed genes. Network pharmacology was used to identify the specific pathways and key target proteins related to breast cancer. Finally, molecular docking was used to validate the results.

RESULTS

In our study, 237 targets were predicted for 15 potential active ingredients found in Poria cocos. An interaction network of predicted targets and genes differentially regulated in breast cancers was constructed. Based on the constructed network and further analysis including network topology, KEGG, survival analysis, and gene set enrichment analysis, 3 primary nodes were identified as key potential targets that were significantly enriched in the PPAR signaling pathway.

CONCLUSION

The results showed that potential active ingredients of Poria cocos might interfere with breast cancer through synergistic regulation of PTGS2, ESR1, and FOS.

N6-Methyladenosine modification of the TRIM7 positively regulates tumorigenesis and chemoresistance in osteosarcoma through ubiquitination of BRMS1

BACKGROUND

Metastasis is the leading cause of death in patients with osteosarcoma. Some of these patients fail to respond to chemotherapy and die of metastasis within a short period. Therefore, it is important to identify novel biomarkers to improve the diagnosis and treatment of osteosarcoma. TRIM7 is a member of the tripartite motif (TRIM) family protein that is involved in various pathological conditions including cancer; however, its role in osteosarcoma remains elusive.

METHODS

Cell proliferation, invasion and migration were measured by CCK-8 and Transwell. Immunoprecipitation and mass spectrometry analysis were used to identify candidate proteins associated with TRIM7. Immunoprecipitation, immunofluorescence, pull down and ubiquitination assay were performed to examine the regulation between TRIM7 and its candidate protein. m6A modification of TRIM7 was measured by RNA immunoprecipitation.

FINDINGS

TRIM7 expression was upregulated in osteosarcoma tissues and was an independent risk factor in predicting poor prognosis. TRIM7 regulates osteosarcoma cell migration and invasion through ubiquitination of breast cancer metastasis suppressor 1 (BRMS1). Moreover, chemoresistance was readily observed in osteosarcoma cells and in patient-derived xenograft (PDX) mice with higher TRIM7 levels. Loss of TRIM7 m6A modification was observed in osteosarcoma tissues. METTL3 and YTHDF2 were the main factors involved in the aberrant m6A modification of TRIM7.

INTERPRETATION

Overall, our findings show that TRIM7 plays a key role in regulating metastasis and chemoresistance in osteosarcoma through ubiquitination of BRMS1.

FUNDING

This work was financially supported by grants of NSFC (81001192, 81672658 and 81972521) and National Key Research Project of Science and Technology Ministry (2016YFC0106204).

UV-type specific alteration of miRNA expression and its association with tumor progression and metastasis in SCC cell lines

PURPOSE

UV exposure is the main risk factor for development of cutaneous squamous cell carcinoma (cSCC). While early detection greatly improves cSCC prognosis, locally advanced or metastatic cSCC has a severely impaired prognosis. Notably, the mechanisms of progression to metastatic cSCC are not well understood. We hypothesized that UV exposure of already transformed epithelial cSCC cells further induces changes which might be involved in the progression to metastatic cSCCs and that UV-inducible microRNAs (miRNAs) might play an important role.

METHODS

Thus, we analyzed the impact of UV radiation of different quality (UVA, UVB, UVA + UVB) on the miRNA expression pattern in established cell lines generated from primary and metastatic cSCCs (Met-1, Met-4) using the NanoString nCounter platform.

RESULTS

This analysis revealed that the expression pattern of miRNAs depends on both the cell line used per se and on the quality of UV radiation. Comparison of UV-induced miRNAs in cSCC cell lines established from a primary tumor (Met-1) and the respective (un-irradiated) metastasis (Met-4) suggest that miR-7-5p, miR-29a-3p and miR-183-5p are involved in a UV-driven pathway of progression to metastasis. This notion is supported by the fact that these three miRNAs build up a network of 81 potential target genes involved e.g. in UVA/UVB-induced MAPK signaling and regulation of the epithelial-mesenchymal transition. As an example, PTEN, a target of UV-upregulated miRNAs (miR-29a-3p, miR-183-5p), could be shown to be down-regulated in response to UV radiation. We further identified CNOT8, the transcription complex subunit 8 of the CCR4-NOT complex, a deadenylase removing the poly(A) tail from miRNA-destabilized mRNAs, in the center of this network, targeted by all three miRNAs.

CONCLUSION

In summary, our results demonstrate that UV radiation induces an miRNA expression pattern in primary SCC cell line partly resembling those of metastatic cell line, thus suggesting that UV radiation impacts SCC progression beyond initiation.

The Search of miRNA Related to Invasive Growth of Nonfunctioning Gonadotropic Pituitary Tumors

PURPOSE

Nonfunctioning gonadotropic pituitary neuroendocrine tumors (PitNETs) are among the most frequent neoplasms of pituitary gland. Although PitNETs are commonly considered benign, a notable part of patients suffer from tumor recurrence after treatment. Invasive growth of pituitary tumor is among the most important prognostic factors. Since molecular features of invasiveness are of potential clinical usefulness, this study was aimed to verify whether invasive and noninvasive nonfunctioning gonadotropic PitNETs differ in the miRNA expression profile and whether the differences could provide a possible molecular classifier.

METHODS

miRNA profiles were determined in 20 patients (11 invasive and 9 noninvasive tumors) using next-generation sequencing. The expression of selected miRNAs was assessed in the independent cohort of 80 patients with qRT-PCR.

RESULTS

When miRNA profiles of invasive and noninvasive tumors were compared, 29 miRNAs were found differentially expressed. Hsa-miR-184, hsa-miR-181a-2-3p, hsa-miR-93-3p, hsa-miR-574-5p, hsa-miR-185-5p, and hsa-miR-3200-5p showed a potential clinical value according to ROC curve analysis. Unfortunately, differential expression of only hsa-miR-185-5p was confirmed in the validation cohort, with AUG at 0.654.

CONCLUSION

Differences in miRNAs expression profiles in invasive and noninvasive gonadotropic PitNETs are slight and the level of miRNA expression seems not to be applicable as useful classifier of tumor invasiveness.

miRNA signatures in childhood sarcomas and their clinical implications

Progresses in multimodal treatments have significantly improved the outcomes for childhood cancer. Nonetheless, for about one-third of patients with Ewing sarcoma, rhabdomyosarcoma, or osteosarcoma steady remission has remained intangible. Thus, new biomarkers to improve early diagnosis and the development of precision-targeted medicine remain imperative. Over the last decade, remarkable progress has been made in the basic understanding of miRNAs function and in interpreting the contribution of their dysregulation to cancer development and progression. On this basis, this review focuses on what has been learned about the pivotal roles of miRNAs in the regulation of key genes implicated in childhood sarcomas.

Epigenetics mechanisms mediate the miR-125a/BRMS1 axis to regulate invasion and metastasis in gastric cancer

Purpose

Altered expression of breast cancer metastasis suppressor 1 (BRMS1), is a tumor suppressor, which is found in many types of cancers, including gastric cancer (GC), but the mechanism by which BRMS1 inhibits invasion and metastasis in GC is unknown. The aim of the study was to investigate the molecular mechanisms of miR-125a/BRMS1 in GC.

Materials and methods

The expression of BRMS1 and miR-125a were detected by quantitative real-time PCR (qRT-PCR) and analyzed by bioinformatics. BSP and MSP were used to detecte the methylation status of miR-125a and BRMS1 which was treated by 5-Aza or not. Western Blot and qRT-PCR were used to analyze the expression of BRMS1 and EZH2. Transwell was performed to explore the invasion and metastasis ability of GC cells. The nude mice were used for the tumor formation assay.

Results

BRMS1 may be regulated by copy number variation (CNV), methylation and miR-125a-5p. As one of the essential components of PRC2, EZH2 is an important regulatory factor resulting in the low expression of miR-125a. An epigenetic mechanism mediates the miR-125a/BRMS1 axis to inhibit the invasion and metastasis of GC cells. In vivo experiments, it is also showed that BRMS1 is involved in invasion and metastasis but not the proliferation in GC.

Conclusion

These studies shed light on the mechanism of BRMS1 inhibition of GC invasion and metastasis and the development of new drugs targeting the miR-125a/BRMS1 axis, which will be a promising therapeutic strategy for GC and other human cancers.

BRMS1 downregulation is a poor prognostic biomarker in anaplastic thyroid carcinoma patients

Background

Anaplastic thyroid carcinoma (ATC) is the most aggressive cancer in humans with no optimal treatment strategy available. The molecular mechanisms of ATC remain unclear. The aim of this study was to investigate the prognostic value and role of BRMS1 in the progression of ATC.

Methods

BRMS1 expression was examined in thyroid cell lines using Western blot analysis. Immunohistochemistry was also performed to assess BRMS1 expression in ATC and papillary thyroid cancer (PTC) tissue. Cell proliferation assays, colony formation analysis, cell migration assays, cell apoptosis analysis, and animal studies were used to examine the effects of BRMS1 expression on ATC progression.

Results

The expression of BRMS1 was significantly lower in ATC than in PTC and was associated with poor prognosis in ATC patients. Downregulation of BRMS1 expression promoted the proliferation and migration of 8505C cells and decreased their expression of CX43. Over-expressed BRMS1 promoted the apoptosis and impaired the proliferation and migration of CAL-62 cells via upregulated CX43. In vivo, BRMS1 significantly promoted apoptosis and impaired cell proliferation.

Conclusion

Taken together, these findings demonstrate that decreased expression of BRMS1 is a poor prognostic biomarker in ATC patients. BRMS1 significantly promoted apoptosis and impaired cell proliferation via CX43 and P53. Loss of BRMS1 expression is therefore, one of the key pathomechanisms in ATC.

MicroRNA-432 is downregulated in osteosarcoma and inhibits cell proliferation and invasion by directly targeting metastasis-associated in colon cancer-1

The aberrant expression of microRNAs (miRNAs/miRs) in osteosarcoma (OS) has been demonstrated in previous studies, and deregulation of miRNA expression has been associated with several types of cancer, including OS development and progression. Therefore, identifying the functional role of miRNAs in OS onset and development may facilitate the identification of novel and effective therapeutic targets for the treatment of patients with OS. Previous studies have demonstrated that miR-432 is involved in tumor formation and progression in several types of cancer. However, the expression pattern, functional role and underlying mechanism of miR-432 in OS remain unknown. In the current study, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to measure miR-432 expression levels in OS tissue samples and cell lines. The effect of miR-432 overexpression on OS cell proliferation and invasion was detected using Cell Counting Kit-8 and Transwell invasion assays, respectively. Bioinformatics analysis was used to predict metastasis-associated in colon cancer 1 (MACC1) as a putative target of miR-432 and this was confirmed using a dual-luciferase reporter assay, RT-qPCR and western blot analysis. The current study demonstrated that miR-432 expression levels were significantly reduced in OS tissue samples and cell lines. In addition, functional assays revealed that overexpression of miR-432 significantly decreased OS cell proliferation and invasion. Furthermore, MACC1 was identified as a direct target gene of miR-432 in OS. MACC1 expression levels were significantly increased in OS tissue samples and an inverse correlation was observed between miR-432 and MACC1 expression in OS tissue samples. In addition, rescue experiments demonstrated that overexpression of MACC1 partially reversed the anti-proliferative and anti-invasive effects of miR-432 in OS cells. In conclusion, the present study demonstrated that miR-432 inhibited OS cell proliferation and invasion in vitro through direct targeting of MACC1, and miR-432 may be a potential therapeutic target for the treatment of OS.