miRNA-30 Family Members Inhibit Breast Cancer Invasion, Osteomimicry, and Bone Destruction by Directly Targeting Multiple Bone Metastasis-Associated Genes

Protective effects of miR-24-2-5p in early stages of breast cancer bone metastasis

BACKGROUND

Bone is the most frequent site of metastasis for breast cancer (BC). Metastatic BC cells interact with bone cells, including osteoclasts and osteoblasts, creating a cancer niche where they seed and proliferate. MicroRNAs (miRNAs) are regulators of breast-to-bone metastasis progression. MiR-24-2-5p has previously been shown to have roles in both breast cancer progression and inhibition of osteogenic differentiation. However, a direct link between miR-24-2-5p activity and the onset of bone metastasis remains ill-defined.

METHODS

Analysis of the expression of miR-24 forms (miR-24-2-5p, miR-24-3p, miR-24-1-5p) in the serum from early-stage BC patients at baseline (time of surgery) was conducted. MiR-24-2-5p overexpression in BC cells (NW1, a luc2-positive subpopulation of MDA-MB-231, and MCF7) was obtained by miRNA mimic transfection or lentivirus transduction. MiR-24-2-5p downregulation in BC cells (ZR-75-1, T-47D, SK-BR-3) was obtained by miRNA inhibitor transfection. Cell proliferation, migration and/or invasion assays were performed to assess BC cell functions after modulation of miR-24-2-5p expression. An animal model was used to assess the effect of miR-24-2-5p overexpression on early BC metastasis formation, as judged by bioluminescence imaging, and on bone remodelling, following measurement of circulating bone resorption (CTX-I) and bone formation (P1NP) markers. The effect of conditioned medium from miR-24-2-5p-overexpressing BC cells on human and murine osteoclast differentiation was investigated. Endogenous miR-24-2-5p expression levels were also quantified during murine osteoclast differentiation. RNA-sequencing (RNA-seq) analysis of BC cells was performed to evaluate transcriptomic changes associated with miR-24-2-5p overexpression. Selected modulated transcripts upon miR-24-2-5p overexpression were further validated by real-time qPCR.

RESULTS

Low expression levels of miR-24-2-5p, but not other miR-24 forms (miR-24-3p, miR-24-1-5p), in the serum from early-stage BC patients were associated with a high risk to develop future (bone) metastases. MiR-24-2-5p was also present in small extracellular vesicles secreted from BC cells. Forced expression of miR-24-2-5p in BC cells (NW1, MCF7) reduced their malignant traits (migration, invasion, and proliferation) in vitro. Furthermore, miR-24-2-5p overexpression in NW1 cells reduced metastasis, particularly in bone, and decreased bone turnover in vivo. RNA-seq and real-time qPCR analyses of NW1 and MCF7 cells overexpressing miR-24-2-5p showed the downregulation of common transcripts (CNNM4, DCTD, FMR1, PIGS, HLA-A, ICK, SH3BGRL2, WDFY, TRAF9B, IL6ST, PEX10, TRIM59). The conditioned medium from BC cells overexpressing miR-24-2-5p decreased human and murine osteoclast differentiation in vitro. Additionally, endogenous miR-24-2-5p expression levels in murine bone marrow-derived monocytes decreased during their differentiation into osteoclasts, further suggesting an inhibitory role for miR-24-2-5p during osteoclastogenesis.

CONCLUSION

MiR-24-2-5p exerts multiple protective roles in the early steps of BC bone metastasis by reducing malignant BC cell traits and tumour cell dissemination in bone, as well as by reducing the differentiation of precursors into mature osteoclasts.

Unveiling miRNA30b's Role in Suppressing ADAM12 to Combat Triple-Negative Breast Cancer

Background: Triple-negative breast cancer, a subtype of breast cancer, is characterized by a poor prognosis. Recent studies have shown that miRNA30b acts as an oncogene and is vital for the proliferation of malignancies across various systems. This study aimed to elucidate the impact of miRNA30b on the proliferation, migration, and invasion capabilities of breast cancer cells in vitro. Methods: Triple-negative breast cancer cell lines MDA-MB-231 were transiently transfected with miRNA30b inhibitor, mimic, or the negative control by Lipofectamine 2000. Successful transfection was confirmed by quantitative real-time polymerase chain reaction (qRT-PCR). Functional assays, including CCK8, clone formation, scratch, and transwell assays, were conducted to evaluate the proliferation, invasion, and migration ability of MDA-MB-231 cells in each group. The target protein of miRNA30b was determined using an online prediction data website, and the dual-luciferase assay confirmed whether there was a binding site between miRNA30b and ADAM12. The effect was further verified by Western blot analysis. Results: MDA-MB-231 cells were transfected with miRNA30b inhibitor, mimic, and negative control. miRNA30b expression was downregulated in the cells. Relative to the negative control group, miRNA30b expression significantly increased in the mimic group and decreased in the miRNA30b inhibitor group, with the differences being statistically significant. The miRNA30b mimic group exhibited a significant increase in miRNA30b expression and a corresponding promotion of cell proliferation, colony formation, and migration. Conversely, the miRNA30b inhibitor group displayed significantly reduced miRNA30b expression and suppressed cell proliferation, colony formation, and migration abilities compared to the negative control cells. Bioinformatics software predicted ADAM12 as a potential target of miRNA30b. Dual-luciferase assays confirmed the presence of a binding site between miRNA30b and ADAM12. Western blot analysis revealed that overexpression of miRNA30b downregulated ADAM12 expression in MDA-MB-231 cells. Conclusions: miRNA30b could promote proliferation, migration, and invasion of TNBC cell lines MDA-MB-231. The effect of miRNA30b on triple-negative breast cancer would be achieved partly at least through inhibiting the expression of ADAM12.

Pre-metastatic niche: formation, characteristics and therapeutic implication

Distant metastasis is a primary cause of mortality and contributes to poor surgical outcomes in cancer patients. Before the development of organ-specific metastasis, the formation of a pre-metastatic niche is pivotal in promoting the spread of cancer cells. This review delves into the intricate landscape of the pre-metastatic niche, focusing on the roles of tumor-derived secreted factors, extracellular vesicles, and circulating tumor cells in shaping the metastatic niche. The discussion encompasses cellular elements such as macrophages, neutrophils, bone marrow-derived suppressive cells, and T/B cells, in addition to molecular factors like secreted substances from tumors and extracellular vesicles, within the framework of pre-metastatic niche formation. Insights into the temporal mechanisms of pre-metastatic niche formation such as epithelial-mesenchymal transition, immunosuppression, extracellular matrix remodeling, metabolic reprogramming, vascular permeability and angiogenesis are provided. Furthermore, the landscape of pre-metastatic niche in different metastatic organs like lymph nodes, lungs, liver, brain, and bones is elucidated. Therapeutic approaches targeting the cellular and molecular components of pre-metastatic niche, as well as interventions targeting signaling pathways such as the TGF-β, VEGF, and MET pathways, are highlighted. This review aims to enhance our understanding of pre-metastatic niche dynamics and provide insights for developing effective therapeutic strategies to combat tumor metastasis.

Deep self-reconstruction driven joint nonnegative matrix factorization model for identifying multiple genomic imaging associations in complex diseases

OBJECTIVE

Comprehensive analysis of histopathology images and transcriptomics data enables the identification of candidate biomarkers and multimodal association patterns. Most existing multimodal data association studies are derived from extensions of the joint nonnegative matrix factorization model for identifying complex data associations, which can make full use of clinical prior information. However, the raw data were usually taken as the input without considering the underlying complex multi-subspace structure, influencing the subsequent integration analysis results.

METHODS

This study proposed a deep-self reconstructed joint nonnegative matrix factorization (DSRJNMF) model to use self-expressive properties to reconstruct the raw data to characterize the similarity structure associated with clinical labels. Then, the sparsity, orthogonality, and regularization constraints constructed from prior information are added to the DSRJNMF model to determine the sparse set of biologically relevant features across modalities.

RESULTS

The algorithm has been applied to identify the imaging genetic association of triple negative breast cancer (TNBC). Multilevel experimental results demonstrate that the proposed algorithm better estimates potential associations between pathological image features and miRNA-gene and identifies consistent multimodal imaging genetic biomarkers to guide the interpretation of TNBC.

CONCLUSION

The propose method provides a novel idea of data association analysis oriented to complex diseases.

Advances in Diet and Physical Activity in Breast Cancer Prevention and Treatment

There is currently a growing interest in diets and physical activity patterns that may be beneficial in preventing and treating breast cancer (BC). Mounting evidence indicates that indeed, the so-called Mediterranean diet (MedDiet) and regular physical activity likely both help reduce the risk of developing BC. For those who have already received a BC diagnosis, these interventions may decrease the risk of tumor recurrence after treatment and improve quality of life. Studies also show the potential of other dietary interventions, including fasting or modified fasting, calorie restriction, ketogenic diets, and vegan or plant-based diets, to enhance the efficacy of BC therapies. In this review article, we discuss the biological rationale for utilizing these dietary interventions and physical activity in BC prevention and treatment. We highlight published and ongoing clinical studies that have applied these lifestyle interventions to BC patients. This review offers valuable insights into the potential application of these dietary interventions and physical activity as complimentary therapies in BC management.

The Involvement of microRNAs in Bone Remodeling Signaling Pathways and Their Role in the Development of Osteoporosis

Bone remodeling, crucial for maintaining the balance between bone resorption and formation, relies on the coordinated activity of osteoclasts and osteoblasts. During osteoclastogenesis, hematopoietic stem cells (HSCs) differentiate into the osteoclast lineage through the signaling pathways OPG/RANK/RANKL. On the other hand, during osteoblastogenesis, mesenchymal stem cells (MSCs) differentiate into the osteoblast lineage through activation of the signaling pathways TGF-β/BMP/Wnt. Recent studies have shown that bone remodeling is regulated by post-transcriptional mechanisms including microRNAs (miRNAs). miRNAs are small, single-stranded, noncoding RNAs approximately 22 nucleotides in length. miRNAs can regulate virtually all cellular processes through binding to miRNA-response elements (MRE) at the 3' untranslated region (3'UTR) of the target mRNA. miRNAs are involved in controlling gene expression during osteogenic differentiation through the regulation of key signaling cascades during bone formation and resorption. Alterations of miRNA expression could favor the development of bone disorders, including osteoporosis. This review provides a general description of the miRNAs involved in bone remodeling and their significance in osteoporosis development.

NCAPD3 exerts tumor-promoting effects in prostatic cancer via dual impact on miR-30a-5p by STAT3-MALAT1 and MYC

Non-SMC condensin II complex subunit D3 (NCAPD3) is a subunit of the non-structural maintenance of chromosomes condensin II complex, which involves chromosome condensation and segregation during mitosis. NCAPD3 has recently been demonstrated as a crucial oncogenic factor. However, the underlying mechanism of NCAPD3 in prostate cancer (PCa) remains not completely clear. In this study, we confirmed that lncRNA MALAT1 was induced by NCAPD3-STAT3, and the expression of miR-30a-5p was controlled by NCAPD3 in PCa cells by miRNA-seq. Through quantitative real-time PCR, fluorescence in situ hybridization, western blotting, and immunohistochemistry assay, we demonstrated that miR-30a-5p was lowly expressed in PCa cells and tissues compared to the controls, which was contrary to NCAPD3 expression and markedly downregulated by NCAPD3. Then, MALAT1 was analyzed for the complementary sequence in the potential interaction with miR-30a-5p by using the predicted target module of public databases. Dual-luciferase reporter assay and RNA immunoprecipitation were carried out to verify that MALAT1 functioned as a sponge for miR-30a-5p to reduce miR-30a-5p expression. Meanwhile, MYC acted as a transcriptional repressor to directly bind the promoter of the miR-30a-5p located gene and repress the miR-30a-5p expression. Furthermore, the upregulation of NCAPD3 on cell viability and migration was significantly attenuated in PC-3 cells when miR-30a-5p was overexpressed. NCAPD3 overexpression also accelerated tumor growth in the xenograft mouse model and repressed miR-30-5p. In summary, this work elucidates NCAPD3 inhibits miR-30a-5p through two pathways: increasing STAT3-MALAT1 to sponge miR-30a-5p and increasing MYC to directly inhibit miR-30a-5p transcription, which could serve as potential therapeutic targets for prostate cancer.

LOX, but not LOXL2, promotes bone metastasis formation and bone destruction in triple-negative breast cancer

The primary function of the lysyl oxidase (LOX) family, including LOX and its paralogue LOX-like (LOXL)-2, is to catalyze the covalent crosslinking of collagen and elastin in the extracellular matrix. LOX and LOXL2 are also facilitating breast cancer invasion and metastatic spread to visceral organs (lungs, liver) in vivo. Conversely, the contribution of LOX and LOXL2 to breast cancer bone metastasis remains scant. Here, using gene overexpression or silencing strategies, we investigated the role of LOX and LOXL2 on the formation of metastatic osteolytic lesions in animal models of triple negative breast cancer. In vivo, the extent of radiographic metastatic osteolytic lesions in animals injected with LOX-overexpressing [LOX(+)] tumor cells was 3-fold higher than that observed in animals bearing tumors silenced for LOX [LOX(-)]. By contrast, the extent of osteolytic lesions between LOXL2(+) and LOXL2(-) tumor-bearing animals did not differ, and was comparable to that observed with LOX(-) tumor-bearing animals. In situ, TRAP staining of bone tissue sections from the hind limbs of LOX(+) tumor-bearing animals was substantially increased compared to LOX(-), LOXL2(+) and LOXL2(-)-tumor-bearing animals, which was indicative of enhanced active-osteoclast resorption. In vitro, tumor-secreted LOX increased osteoclast differentiation induced by RANKL, whereas LOXL2 seemed to counteract LOX's pro-osteoclastic activity. Furthermore, LOX (but not LOXL2) overexpression in tumor cells induced a robust production of IL-6, the latter being a pro-osteoclastic cytokine. Based on these findings, we propose a model in which LOX and IL-6 secreted from tumor cells act in concert to enhance osteoclast-mediated bone resorption that, in turn, promotes metastatic bone destruction in vivo.

METTL3-Mediated m6A Modification Regulates the Osteogenic Differentiation through LncRNA CUTALP in Periodontal Mesenchymal Stem Cells of Periodontitis Patients

Objective

Periodontitis is a chronic inflammatory disease that causes loss of periodontal support tissue. Our objective was to investigate the mechanism by which METTL3-mediated N6-methyladenosine modification regulates the osteogenic differentiation through lncRNA in periodontal mesenchymal stem cells in patients with periodontitis (pPDLSCs). Material and Methods. We carried out a series of experiments, including methylated RNA immunoprecipitation-PCR, quantitative real-time polymerase chain reaction, and western blotting. The expressions of alkaline phosphatase (ALP), Runx2, Col1, Runx2 protein level, ALP staining, and Alizarin red staining were used to demonstrate the degree of osteogenic differentiation.

Results

We found that METTL3 was the most significantly differentially expressed methylation-related enzyme in pPDLSCs and promoted osteogenic differentiation of pPDLSCs. METTL3 regulated the stability and expression of lncRNA CUTALP, while lncRNA CUTALP promoted osteogenic differentiation of pPDLSCs by inhibiting miR-30b-3p. At different time points of osteogenic differentiation, lncRNA CUTALP expression was positively correlated with Runx2, while miR-30b-3p showed the opposite pattern. The attenuated osteogenic differentiation induced by METTL3 knockdown was recovered by lncRNA CUTALP overexpression. The attenuated osteogenic differentiation induced by lncRNA CUTALP knockdown could be reversed by the miR-30b-3p inhibitor.

Conclusions

In summary, METTL3/lncRNA CUTALP/miR-30b-3p/Runx2 is a regulatory network in the osteogenic differentiation of pPDLSCs.

Research Progress on the Anticancer Activity of Plant Polysaccharides

Tumor is a serious threat to human health, with extremely high morbidity and mortality rates. However, tumor treatment is challenging, and the development of antitumor drugs has always been a significant research focus. Plant polysaccharides are known to possess various biological activities. They have many pharmacological properties such as immunomodulation, antitumor, antiviral, antioxidative, antithrombotic, and antiradiation effects, reduction of blood pressure and blood sugar levels, and protection from liver injury. Among these effects, the antitumor effect of plant polysaccharides has been widely studied. Plant polysaccharides can inhibit tumor proliferation and growth by inhibiting tumor cell invasion and metastasis, inducing cell apoptosis, affecting the cell cycle, and regulating the tumor microenvironment. They also have the characteristics of safety, high efficiency, and low toxicity, which can alleviate, to a certain extent, the adverse reactions caused by traditional tumor treatment methods such as surgery, radiotherapy, and chemotherapy. Therefore, this paper systematically summarizes the direct antitumor effects of plant polysaccharides, their regulatory effects on the tumor microenvironment, and intervening many common high-incidence tumors in other ways. It also provides data support for the administration of plant polysaccharides in modern tumor drug therapy, enabling the identification of new targets and development of new drugs for tumor therapy.

Expression of nonmuscle myosin IIC is regulated by non-canonical binding activity of miRNAs

The expression of mechanoresponsive nonmuscle myosin II (NMII)C is found to be inducible during tumor progression, but its mechanism is yet to be explored. Here, we report a group of microRNAs (mmu-miR-200a-5p, mmu-miR-532-3p, mmu-miR-680, and mmu-miR-1901) can significantly repress the expression of nonmuscle myosin IIC (NMIIC). Interestingly, these microRNAs have both canonical and non-canonical binding sites at 3/UTR and coding sequence (CDS) of NMIIC's heavy chain (HC) mRNA. Each of the miRNA downregulates NMHC-IIC to a different degree as assessed by dual-luciferase and immunoblot analyses. When we abolish the complementary base pairing at canonical binding site, mmu-miR-532-3p can still bind at non-canonical binding site and form Argonaute2 (AGO2)-miRNA complex to downregulate the expression of NMIIC. Modulating the expression of NMIIC by miR-532-3p in mouse mammary tumor cells, 4T1, increases its tumorigenic potential both in vitro and in vivo. Together, these studies provide the functional role of miRNA's non-canonical binding mediated NMIIC regulation in tumor cells.

Predictive and prognostic biomarkers of bone metastasis in breast cancer: current status and future directions

The most common site of metastasis in breast cancer is the bone, where the balance between osteoclast-mediated bone resorption and osteoblast-mediated bone formation is disrupted. This imbalance causes osteolytic bone metastasis in breast cancer, which leads to bone pain, pathological fractures, spinal cord compression, and other skeletal-related events (SREs). These complications reduce patients' quality of life significantly and have a profound impact on prognosis. In this review, we begin by providing a brief overview of the epidemiology of bone metastasis in breast cancer, including current diagnostic tools, treatment approaches, and existing challenges. Then, we will introduce the pathophysiology of breast cancer bone metastasis (BCBM) and the animal models involved in the study of BCBM. We then come to the focus of this paper: a discussion of several biomarkers that have the potential to provide predictive and prognostic value in the context of BCBM-some of which may be particularly compatible with more comprehensive liquid biopsies. Beyond that, we briefly explore the potential of new technologies such as single-cell sequencing and organoid models, which will improve our understanding of tumor heterogeneity and aid in the development of improved biomarkers. The emerging biomarkers discussed hold promise for future clinical application, aiding in the prevention of BCBM, improving the prognosis of patients, and guiding the implementation of personalized medicine.

hsa_circ_0005991 promotes epithelial-mesenchymal transition by regulating miR-30b-3p/Cdc42EP1 axis in ovary endometriosis

Endometriosis is a common gynecological disease with an enigmatic pathogenesis. This work explored the function of hsa_circ_0005991 in ovarian endometriosis. High-throughput RNA-Seq was conducted in five matched ectopic (EC) and eutopic (EU) samples. Further, several types of cell function experiments were conducted. According to bioinformatics analysis, a competing endogenous RNA network was established. It included 5 circRNAs, 13 miRNAs, and 551 mRNAs. The expression levels of hsa_circ_0005991 and Cdc42EP1 were significantly elevated, while miR-30b-3p was reduced in the EC group. Upregulation of hsa_circ_0005991 raised Cdc42EP1 levels, induced EMT, and boosted Ishikawa cell proliferation, migration, and invasion. hsa_circ_0005991 knockdown indicated the opposite effects. When co-transfected with miR-30b-3p mimics or inhibitors, these effects could be reversed, respectively. Western blot assays showed alterations of EMT markers in EC samples. hsa_circ_0005991/miR-30b-3p/Cdc42EP1 axis promotes the EMT process in endometriosis, which may offer a theoretical foundation for the mechanism exploration and therapy of this disease.

Liposome-encapsulated zoledronate increases inflammatory macrophage population in TNBC tumours

BACKGROUND

Tumour associated macrophages (TAMs) are important players in breast tumour progression and metastasis. Clinical and preclinical evidence suggests a role for zoledronate (ZOL) in breast cancer metastasis prevention. Further, zoledronate is able to induce inflammatory activation of monocytes and macrophages, which can be favourable in cancer treatments. The inherent bone tropism of zoledronate limits its availability in soft tissues and tumours. In this study we utilised an orthotopic murine breast cancer model to evaluate the possibility to use liposomes (EMP-LIP) to target zoledronate to tumours to modify TAM activation.

METHODS

Triple-negative breast cancer 4T1 cells were inoculated in the 4th mammary fat pad of female Balb/c mice. Animals were divided according to the treatment: vehicle, ZOL, EMP-LIP and liposome encapsulated zoledronate (ZOL-LIP). Treatment was done intravenously (with tumour resection) and intraperitoneally (without tumour resection). Tumour growth was followed by bioluminescence in vivo imaging (IVIS) and calliper measurements. Tumour-infiltrating macrophages were assessed by immunohistochemical and immunofluorescence staining. Protein and RNA expression levels of inflammatory transcription factors and cytokines were measured by Western Blotting and Taqman RT-qPCR.

RESULTS

Liposome encapsulated zoledronate (ZOL-LIP) treatment suppressed migration of 4T1 cell in vitro. Tumour growth and expression of the angiogenic marker CD34 were reduced upon both ZOL and ZOL-LIP treatment in vivo. Long-term ZOL-LIP treatment resulted in shift towards M1-type macrophage polarization, increased CD4 T cell infiltration and activation of NF-κB indicating changes in intratumoural inflammation, whereas ZOL treatment showed similar but non-significant trends. Moreover, ZOL-LIP had a lower bisphosphonate accumulation in bone compared to free ZOL.

CONCLUSION

Results show that the decreased bisphosphonate accumulation in bone promotes the systemic anti-tumour effect of ZOL-LIP by increasing inflammatory response in TNBC tumours via M1-type macrophage activation.

Dysregulation of MicroRNAs in Adult Osteogenesis Imperfecta: The miROI Study

As epigenetic regulators of gene expression, circulating micro-RiboNucleic Acids (miRNAs) have been described in several bone diseases as potential prognostic markers. The aim of our study was to identify circulating miRNAs potentially associated with the severity of osteogenesis imperfecta (OI) in three steps. We have screened by RNA sequencing for the miRNAs that were differentially expressed in sera of a small group of OI patients versus controls and then conducted a validation phase by RT-qPCR analysis of sera of a larger patient population. In the first phase of miROI, we found 79 miRNAs that were significantly differentially expressed. We therefore selected 19 of them as the most relevant. In the second phase, we were able to validate the significant overexpression of 8 miRNAs in the larger OI group. Finally, we looked for a relationship between the level of variation of the validated miRNAs and the clinical characteristics of OI. We found a significant difference in the expression of two microRNAs in those patients with dentinogenesis imperfecta. After reviewing the literature, we found 6 of the 8 miRNAs already known to have a direct action on bone homeostasis. Furthermore, the use of a miRNA-gene interaction prediction model revealed a 100% probability of interaction between 2 of the 8 confirmed miRNAs and COL1A1 and/or COL1A2. This is the first study to establish the miRNA signature in OI, showing a significant modification of miRNA expression potentially involved in the regulation of genes involved in the physiopathology of OI. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Advances in the study of biomarkers related to bone metastasis in breast cancer

Breast cancer is by far the most common malignancy in females. And bone is the most common site of distant metastasis in breast cancer, accounting for about 65 to 75% of all metastatic breast cancer patients.1,2Bone metastasis is an important factor affecting the prognosis of breast cancer. When patients have early-stage breast cancer without metastasis, their 5-year survival rate is as high as 90%, and once metastasis occurs, their 5-year survival rate will drop to 10%.3 Bone radionuclide imaging (ECT), X-ray, CT scan, MRI and other imaging tests to diagnose breast cancer bone metastasis are commonly used in clinical, It is currently believed that breast cancer bone metastasis is a multistep process: first, breast cancer cells need to acquire invasive and metastatic properties; breast cancer cells enter the blood circulation and migrate from blood breast cancer cells enter the blood circulation and migrate from blood vessels to bone tissue in a targeted manner; breast cancer cells adhere and remain in bone tissue and colonise it; and finally, it leads to bone destruction.4 Several key molecules are involved in breast cancer bone metastasis, and serum biomarkers are generally able to detect pathological changes earlier Several key molecules are involved in breast cancer bone metastasis, and serum biomarkers are generally able to detect pathological changes earlier than imaging.5 This review describes the progress of serum biomarkers for breast cancer bone metastasis.

MiR-662 is associated with metastatic relapse in early-stage breast cancer and promotes metastasis by stimulating cancer cell stemness

BACKGROUND

Breast cancer (BC) metastasis, which often occurs in bone, contributes substantially to mortality. MicroRNAs play a fundamental role in BC metastasis, although microRNA-regulated mechanisms driving metastasis progression remain poorly understood.

METHODS

MiRome analysis in serum from BC patients was performed by TaqMan™ low-density array. MiR-662 was overexpressed following MIMIC-transfection or lentivirus transduction. Animal models were used to investigate the role of miR-662 in BC (bone) metastasis. The effect of miR-662-overexpressing BC cell conditioned medium on osteoclastogenesis was investigated. ALDEFLUOR assays were performed to study BC stemness. RNA-sequencing transcriptomic analysis of miR-662-overexpressing BC cells was performed to evaluate gene expression changes.

RESULTS

High levels of hsa-miR-662 (miR-662) in serum from BC patients, at baseline (time of surgery), were associated with future recurrence in bone. At an early-stage of the metastatic disease, miR-662 could mask the presence of BC metastases in bone by inhibiting the differentiation of bone-resorbing osteoclasts. Nonetheless, metastatic miR-662-overexpressing BC cells then progressed as overt osteolytic metastases thanks to increased stem cell-like traits.

CONCLUSIONS

MiR-662 is involved in BC metastasis progression, suggesting it may be used as a prognostic marker to identify BC patients at high risk of metastasis.

MicroRNA-Based Discovery of Biomarkers, Therapeutic Targets, and Repositioning Drugs for Breast Cancer

Breast cancer treatment can be improved with biomarkers for early detection and individualized therapy. A set of 86 microRNAs (miRNAs) were identified to separate breast cancer tumors from normal breast tissues (n = 52) with an overall accuracy of 90.4%. Six miRNAs had concordant expression in both tumors and breast cancer patient blood samples compared with the normal control samples. Twelve miRNAs showed concordant expression in tumors vs. normal breast tissues and patient survival (n = 1093), with seven as potential tumor suppressors and five as potential oncomiRs. From experimentally validated target genes of these 86 miRNAs, pan-sensitive and pan-resistant genes with concordant mRNA and protein expression associated with in-vitro drug response to 19 NCCN-recommended breast cancer drugs were selected. Combined with in-vitro proliferation assays using CRISPR-Cas9/RNAi and patient survival analysis, MEK inhibitors PD19830 and BRD-K12244279, pilocarpine, and tremorine were discovered as potential new drug options for treating breast cancer. Multi-omics biomarkers of response to the discovered drugs were identified using human breast cancer cell lines. This study presented an artificial intelligence pipeline of miRNA-based discovery of biomarkers, therapeutic targets, and repositioning drugs that can be applied to many cancer types.

Tumor-Suppressive and Immunomodulating Activity of miR-30a-3p and miR-30e-3p in HNSCC Cells and Tumoroids

Head and neck squamous cell carcinomas (HNSCCs) are heterogeneous tumors, well known for their frequent relapsing nature. To counter recurrence, biomarkers for early diagnosis, prognosis, or treatment response prediction are urgently needed. miRNAs can profoundly impact normal physiology and enhance oncogenesis. Among all of the miRNAs, the miR-30 family is frequently downregulated in HNSCC. Here, we determined how levels of the 3p passenger strands of miR-30a and miR-30e affect tumor behavior and clarified their functional role in LA-HNSCC. In a retrospective study, levels of miR-30a-3p and miR-30e-3p were determined in 110 patients and correlated to overall survival, locoregional relapse, and distant metastasis. miR-30a/e-3p were expressed in HNSCC cell lines and HNSCC patient-derived tumoroids (PDTs) to investigate their effect on tumor cells and their microenvironment. Both miRNAs were found to have a prognosis value since low miR-30a/e-3p expression correlates to adverse prognosis and reduces overall survival. Low expression of miR-30a/e-3p is associated with a shorter time until locoregional relapse and a shorter time until metastasis, respectively. miR-30a/e-3p expression downregulates both TGF-βR1 and BMPR2 and attenuates the survival and motility of HNSCC. Results were confirmed in PDTs. Finally, secretomes of miR-30a/e-3p-transfected HNSCC activate M1-type macrophages, which exert stronger phagocytic activities toward tumor cells. miR-30a/e-3p expression can discriminate subgroups of LA-HNSCC patients with different prognosis, making them good candidates as prognostic biomarkers. Furthermore, by targeting members of the TGF-β family and generating an immune-permissive microenvironment, they may emerge as an alternative to anti-TGF-β drugs to use in combination with immune checkpoint inhibitors.

Potential biomarkers for the early detection of bone metastases

The clinical manifestations of bone metastases are diversified while many sites remain asymptomatic at early stage. As the early diagnosis method is not perfect and the early symptoms of tumor bone metastasis are not typical, bone metastasis is not easy to be detected. Therefore, the search for bone metastasis-related markers is effective for timely detection of tumor bone metastases and the development of drugs to inhibit bone metastases. As a result, bone metastases can only be diagnosed when symptoms are found, increasing the risk of developing skeletal-related event (SREs), which significantly impairs the patient's quality of life. Therefore, the early diagnosis of bone metastases is of great importance for the treatment and prognosis of cancer patients. Changes of bone metabolism indexes appear earlier in bone metastases, but the traditional biochemical indexes of bone metabolism lack of specificity and could be interfered by many factors, which limits their application in the study of bone metastases. Some new biomarkers of bone metastases have good diagnostic value, such as proteins, ncRNAs, circulating tumor cells (CTCs). Therefore, this study mainly reviewed the initial diagnostic biomarkers of bone metastases which were expected to provide references for the early detection of bone metastases.

Role of RUNX2 in breast cancer development and drug resistance (Review)

Breast cancer is the most common malignancy and ranks second among the causes of tumor-associated death in females. The recurrence and drug resistance of breast cancer are intractable due to the presence of breast cancer stem cells (BCSCs), which are adequate to initiate tumor formation and refractory to conventional remedies. Runt-related transcription factor 2 (RUNX2), a pivotal transcription factor in mammary gland and bone development, has also been related to metastatic cancer and BCSCs. State-of-the-art research has indicated the retention of RUNX2 expression in a more invasive subtype of breast cancer, and in particular, triple-negative breast cancer development and drug resistance are associated with estrogen receptor signaling pathways. The present review mainly focused on the latest updates on RUNX2 in BCSCs and their roles in breast cancer progression and drug resistance, providing insight that may aid the development of RUNX2-based diagnostics and treatments for breast cancer in clinical practice.

The role of integrin family in bone metabolism and tumor bone metastasis

Integrins have been the research focus of cell-extracellular matrix adhesion (ECM) and cytokine receptor signal transduction. They are involved in the regulation of bone metabolism of bone precursor cells, mesenchymal stem cells (MSCs), osteoblasts (OBs), osteoclasts (OCs), and osteocytes. Recent studies expanded and updated the role of integrin in bone metabolism, and a large number of novel cytokines were found to activate bone metabolism pathways through interaction with integrin receptors. Integrins act as transducers that mediate the regulation of bone-related cells by mechanical stress, fluid shear stress (FSS), microgravity, hypergravity, extracellular pressure, and a variety of physical factors. Integrins mediate bone metastasis of breast, prostate, and lung cancer by promoting cancer cell adhesion, migration, and survival. Integrin-mediated targeted therapy showed promising prospects in bone metabolic diseases. This review emphasizes the latest research results of integrins in bone metabolism and bone metastasis and provides a vision for treatment strategies.

Extracellular Vesicles and Their Zeta Potential as Future Markers Associated with Nutrition and Molecular Biomarkers in Breast Cancer

A nutritional intervention promotes the loss of body and visceral fat while maintaining muscle mass in breast cancer patients. Extracellular vesicles (EVs) and their characteristics can be potential biomarkers of disease. Here, we explore the changes in the Zeta potential of EVs; the content of miRNA-30, miRNA-145, and miRNA-155; and their association with body composition and biomarkers of metabolic risk in breast cancer patients, before and 6 months after a nutritional intervention. Clinicopathological data (HER2neu, estrogen receptor, and Ki67), anthropometric and body composition data, and plasma samples were available from a previous study. Plasma EVs were isolated and characterized in 16 patients. The expression of miRNA-30, miRNA-145, and miRNA-155 was analyzed. The Zeta potential was associated with HER2neu (β = 2.1; p = 0.00), Ki67 (β = -1.39; p = 0.007), estrogen positive (β = 1.57; p = 0.01), weight (β = -0.09; p = 0.00), and visceral fat (β = 0.004; p = 0.00). miRNA-30 was associated with LDL (β = -0.012; p = 0.01) and HDL (β = -0.02; p = 0.05). miRNA-155 was associated with visceral fat (β = -0.0007; p = 0.05) and Ki67 (β = -0.47; p = 0.04). Our results reveal significant associations between the expression of miRNA-30 and miRNA-155 and the Zeta potential of the EVs with biomarkers of metabolic risk and disease prognosis in women with breast cancer; particularly, the Zeta potential of EVs can be a new biomarker sensitive to changes in the nutritional status and breast cancer progression.

Non-Coding RNAs Modulating Estrogen Signaling and Response to Endocrine Therapy in Breast Cancer

The largest part of human DNA is transcribed into RNA that does not code for proteins. These non-coding RNAs (ncRNAs) are key regulators of protein-coding gene expression and have been shown to play important roles in health, disease and therapy response. Today, endocrine therapy of ERα-positive breast cancer (BC) is a successful treatment approach, but resistance to this therapy is a major clinical problem. Therefore, a deeper understanding of resistance mechanisms is important to overcome this resistance. An increasing amount of evidence demonstrate that ncRNAs affect the response to endocrine therapy. Thus, ncRNAs are considered versatile biomarkers to predict or monitor therapy response. In this review article, we intend to give a summary and update on the effects of microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs) on estrogen signaling in BC cells, this pathway being the target of endocrine therapy, and their role in therapy resistance. For this purpose, we reviewed articles on these topics listed in the PubMed database. Finally, we provide an assessment regarding the clinical use of these ncRNA types, particularly their circulating forms, as predictive BC biomarkers and their potential role as therapy targets to overcome endocrine resistance.

Aberrant Cadherin11 expression predicts distant metastasis of gastric cancer

The prognosis of gastric cancer (GC) is significantly affected by distant metastases and postoperative recurrences. Bone metastasis is one of the worst prognostic metastases in GC; however, its molecular mechanisms and predictive biomarkers remain elusive. In prostate and breast cancers, it has been reported that overexpression of Cadherin 11 (CDH11), a mesenchymal cell-cell contact factor, is known to be correlated with bone metastasis. Overexpression of CDH11 mRNA in bulk GC tissues has also been reported to be associated with a worse prognosis. However, a more precise evaluation of CDH11 expression in GC cells is necessary to establish a robust link between CDH11 and metastatic features of GC. We performed immunohistochemical analysis of CDH11 expression in 342 GC cases, of which specimens were obtained at the time of surgery, with a special focus on its aberrant membranous expression in GC cells. The correlations between aberrant CDH11 expression and distant metastases and the prognosis of GC cases were statistically investigated. Approximately half of the GC cases investigated showed aberrant expression of CDH11 in the GC cells of primary lesions. Aberrant CDH11 expression was statistically associated with bone metastasis of GCs. Moreover, metastases to the liver and distant lymph nodes were also statistically correlated with CDH11 expression. Aberrant CDH11 expression in GC cells in primary tumor lesions was shown to be a predictive biomarker of distant metastases in GC. GCs with CDH11 expression require preventive clinical attention for the detection of metastatic lesions.

Breast cancer tumor microenvironment affects Treg/IL-17-producing Treg/Th17 cell axis: Molecular and therapeutic perspectives

The tumor microenvironment (TME) comprises a variety of immune cells, among which T cells exert a prominent axial role in tumor development or anti-tumor responses in patients with breast cancer (BC). High or low levels of anti-inflammatory cytokines, such as transforming growth factor β, in the absence or presence of proinflammatory cytokines, such as interleukin-6 (IL-6), delineate the fate of T cells toward either regulatory T (Treg) or T helper 17 (Th17) cells, respectively. The transitional state of RORγt⁺Foxp3⁺ Treg (IL-17-producing Treg) resides in the middle of this reciprocal polarization, which is known as Treg/IL-17-producing Treg/Th17 cell axis. TME secretome, including microRNAs, cytokines, and extracellular vesicles, can significantly affect this axis. Furthermore, immune checkpoint inhibitors may be used to reconstruct immune cells; however, some of these novel therapies may favor tumor development. Therefore, understanding secretory and cell-associated factors involved in their differentiation or polarization and functions may be targeted for BC management. This review discusses microRNAs, cytokines, and extracellular vesicles (as secretome), as well as transcription factors and immune checkpoints (as cell-associated factors), which influence the Treg/IL-17-producing Treg/Th17 cell axis in BC. Furthermore, approved or ongoing clinical trials related to the modulation of this axis in the TME of BC are described to broaden new horizons of promising therapeutic approaches.

A miRNA-based gene therapy nanodrug synergistically enhances pro-inflammatory antitumor immunity against melanoma

MicroRNA (miRNA)-based gene therapy is a robust approach to treating human cancers. However, the low target specificity and safety issues associated with viral vectors have limited the clinical use of miRNA therapeutics. In the present study, we aimed to develop a biocompatible nanocarrier to deliver the tumor suppressor miR-30a-5p for gene therapy of ocular melanoma. The quasi-mesoporous magnetic nanospheres (MMNs) were prepared by polyelectrolytes-mediated self-assembling Fe₃O₄ nanocrystals; the cationic polymer capped quasi-mesoporous inner tunnels of the MMNs facilitate high miRNA loading and protect from nuclease degradation. Then, the outer layer of the MMNs was modified with a disulfide bond bridged very low molecular weight polyethyleneimine (PEI) network to form redox-responsive nanospheres (rMMNs) that enhance the miRNA payload and enable miRNA release under glutathione-dominant tumor microenvironment. The miR-30a-5p loaded rMMNs nanodrug (miR-30a-5p@rMMNs) upregulated miR-30a-5p level and inhibited malignant phenotypes of ocular melanoma by targeting the transcription factor E2F7 both in vitro and in vivo. Additionally, rMMNs act as an enhancer to increase cancer cell apoptosis by modulating M1-like macrophage polarization and activating Fenton reaction. Thus, the rMMNs is a promising miRNA carrier for gene therapy and could enhance pro-inflammatory immunity in melanoma and other cancers. STATEMENT OF SIGNIFICANCE: • miR-30a-5p@rMMNs inhibited malignant phenotypes of ocular melanoma both in vitro and in vivo. • The rMMNs promoted M1 macrophage polarization thus synergistically enhancing pro-inflammatory anti-tumor immunity against melanoma. • The rMMNs showed no obvious toxicity under the injection dose.

Identification of Three Circulating MicroRNAs in Plasma as Clinical Biomarkers for Breast Cancer Detection

The diagnostic value of microRNAs (miRNAs) for breast cancer (BC) is largely unknown. Here, our research aim was to explore new circulating miRNAs for BC diagnosis. First, we identified 14 common differentially expressed miRNAs in tissues by TCGA_BRCA and GSE97811 datasets and preliminarily validated them in serum by the GSE73002 dataset. Furthermore, we examined three plasma miRNAs in BC patients (n = 108) and healthy subjects (n = 103) by RT−PCR, namely, hsa-miR-100-5p, hsa-miR-191-5p and hsa-miR-342-3p. The levels of these three miRNAs in BC patients were higher than those in healthy controls (p < 0.05). The ROC curve analysis revealed that these three miRNAs had high diagnostic efficacy for BC and early-stage BC. The combination of hsa-miR-100-5p and hsa-miR-191-5p was the optimal combination for the diagnosis of BC and early-stage BC. Additionally, hsa-miR-100-5p was correlated with stage I−II, T1 stage, N0 stage and Luminal A subtype (p < 0.05). Hsa-miR-191-5p and hsa-miR-342-3p were irrelevant to TNM stage, T stage, N stage and molecular subtypes. Meanwhile, the biological function analysis indicated that these three miRNAs are mainly involved in the calcium signaling pathway, MAPK signaling pathway and microRNAs in cancer. In conclusion, these three miRNAs demonstrate a positive effect on detection and discovery in BC.

Toxicity mechanisms regulating bone differentiation and development defects following abnormal expressions of miR-30c targeted by triclosan in zebrafish

As a ubiquitous environmental estrogen-disrupting chemical, triclosan (TCS) can induce severe osteotoxicity; however, the underlying molecular mechanisms remain uncertain. Herein, we evaluated the toxic effects of TCS on the development of cartilage and osteogenesis in 5-dpf zebrafish. Under TCS exposure from 62.5 to 250 μg/L, several osteodevelopmental malformations were observed, such as defect of craniofacial cartilage, pharyngeal arch cartilage dysplasia, and impairments on skeletal mineralization. Further, the morphology of mature chondrocytes became swollen and deformed, their number decreased, nucleus displacement occurred, and most immature chondrocytes were crowded at both ends of ceratobranchial. SEM observation of larval caudal fin revealed that, the layer of collagen fibers and the mineralized calcium nodules were significantly decreased, with the collagen fibers becoming shorter upon TCS exposure. The activity of bone-derived alkaline phosphatase significantly reduced, and marker functional genes related to cartilage and osteoblast development were abnormally expressed. RNA-seq and bioinformatics analysis indicated, that changes in marker genes intimately related to the negative regulation of miR-30c-5p overexpression targeted by TCS, and the up-regulation of miR-30c induced bone developmental defects by inhibiting the bone morphogenetic protein (BMP) signaling pathway. These findings were confirmed by artificially intervening the expression of miR-30c and using BMP pathway agonists in vivo. In sum, TCS induced osteototoxicity by targeting miR-30c up-regulation and interfering in the BMP signaling pathway. These findings enhance mechanistic understanding of TCS-induced spontaneous bone disorders and bone metastatic diseases. Further research is necessary to monitor chronic TCS-exposure levels in surrounding environments and develop relevant safety precautions based on TCS environmental risk.

Weight loss reduces circulating micro-RNA related to obesity and breast cancer in postmenopausal women

Postmenopausal women with overweight or obesity have an increased risk of developing breast cancer but many of the mechanisms underlying this association remain to be elucidated. MicroRNAs (miRNAs), short non-coding single-stranded RNAs, regulate many physiological processes by controlling post-transcriptional regulation of mRNA. We measured circulating miRNA from 192 overweight/obese postmenopausal women (50-75 years) who were part of a randomized controlled trial, comparing independent and combined effects of a 12-month reduced-calorie weight-loss diet and exercise programme, versus control. RNA was extracted from stored plasma samples, and 23 a priori selected miRNA targets related to aetiology of breast cancer or obesity were measured using NanoString nCounter miRNA Expression assays. Changes from baseline to 12-months between controls and women in the diet/exercise weight loss arms were analysed using generalized estimating equations modification of linear regression, adjusted for confounders. We next examined changes in levels of circulating miRNA by amount of weight loss (0-10% versus ≥10%). Participants randomized to weight-loss interventions had statistically significantly greater reductions in miR-122 (-7.25%), compared to controls (+ 33.5%, P = 0.009), and miR-122 levels were statistically significantly correlated with weight loss (rho = 0.24; P = 0.001) Increasing weight loss was associated with greater reductions in miR-122 vs. controls (-11.7% (≥10% weight loss); +2.0% (0-10% weight loss) +33.5% (controls); Ptrend = 0.006), though this was not significant after correction for multiple testing (P = 0.05/23) Our study supports the effect of weight loss on regulation of miRNA.

Updated review of advances in microRNAs and complex diseases: experimental results, databases, webservers and data fusion

MicroRNAs (miRNAs) are gene regulators involved in the pathogenesis of complex diseases such as cancers, and thus serve as potential diagnostic markers and therapeutic targets. The prerequisite for designing effective miRNA therapies is accurate discovery of miRNA-disease associations (MDAs), which has attracted substantial research interests during the last 15 years, as reflected by more than 55 000 related entries available on PubMed. Abundant experimental data gathered from the wealth of literature could effectively support the development of computational models for predicting novel associations. In 2017, Chen et al. published the first-ever comprehensive review on MDA prediction, presenting various relevant databases, 20 representative computational models, and suggestions for building more powerful ones. In the current review, as the continuation of the previous study, we revisit miRNA biogenesis, detection techniques and functions; summarize recent experimental findings related to common miRNA-associated diseases; introduce recent updates of miRNA-relevant databases and novel database releases since 2017, present mainstream webservers and new webserver releases since 2017 and finally elaborate on how fusion of diverse data sources has contributed to accurate MDA prediction.

Heart failure and cancer: From active exposure to passive adaption

The human body seems like a "balance integrator." On the one hand, the body constantly actively receives various outside stimuli and signals to induce changes. On the other hand, several internal regulations would be initiated to adapt to these changes. In most cases, the body could keep the balance in vitro and in vivo to reach a healthy body. However, in some cases, the body can only get to a pathological balance. Actively exposed to unhealthy lifestyles and passively adapting to individual primary diseases lead to a similarly inner environment for both heart failure and cancer. To cope with these stimuli, the body must activate the system regulation mechanism and face the mutual interference. This review summarized the association between heart failure and cancer from active exposure to passive adaption. Moreover, we hope to inspire researchers to contemplate these two diseases from the angle of overall body consideration.

GLDC mitigated by miR-30e regulates cell proliferation and tumor immune infiltration in TNBC

Background

TNBC, whose clinical prognosis is poorer than other subgroups of breast cancer, is a malignant tumor characterized by lack of estrogen receptors, progesterone hormone receptors, and HER2 overexpression. Due to the lack of specific targeted drugs, it is crucial to identify critical factors involved in regulating the progression of TNBC.

Methods

We analyzed the expression profiles of TNBC in TCGA and the prognoses values of GLDC. Correlations of GLDC and tumor immune infiltration were also identified. CCK8 and BrdU incorporation assays were utilized to determine cell proliferation. The mRNA and protein levels were examined by using Real-time PCR and Western blot analysis.

Results

In the present study, we analyzed the mRNA expression profiles of TNBC in TCGA and found that GLDC, a key enzyme in glycine cleavage system, was significantly up-regulated in TNBC tissues and higher expression of GLDC was correlated with a worse prognosis in TNBC. Moreover, the expression of GLDC was negatively correlated with macrophage and monocyte and positively correlated with activated CD4 T cell and type 2 T helper cell in TNBC. Overexpression of GLDC facilitated the proliferation of TNBC cells, whereas GLDC knockdown had the opposite effects. Additionally, miR-30e acts as a functional upstream regulator of GLDC and the inhibitory effects of miR-30e on cell proliferation were mitigated by the reintroduction of GLDC.

Conclusions

These results imply that miR-30e-depressed GLDC acts as a tumor suppressive pathway in TNBC and provides potential targets for the treatment of TNBC.

ITGA5 Promotes Tumor Progression through the Activation of the FAK/AKT Signaling Pathway in Human Gastric Cancer

Background

ITGA5 is an adhesion molecule that integrates the intracellular structures with the extracellular matrix to perform biological functions. However, ITGA5 is highly expressed in a variety of tumors and is involved in tumor progression by promoting cell proliferation and metastasis. Nevertheless, little research has been performed on its function in gastric cancer. Therefore, the aim of this study was to investigate the role of ITGA5 in gastric cancer, focusing on the mechanism regulating the proliferation, invasion and migration.

Methods

The expression of ITGA5 in gastric cancer tissues was assessed by the use of molecular bioinformatics databases and high-throughput sequencing of gastric cancer tissues from patients. Western blot, qPCR, and immunohistochemistry were performed to detect the expression of ITGA5 in samples from gastric cancer patients and gastric cancer cell lines. Furthermore, the ITGA5 gene was silenced and overexpressed in gastric cancer cells, and the effect on proliferation, invasion, migration, and tumorigenic ability was assessed.

Results

ITGA5 mRNA and protein expression were upregulated in gastric cancer cell lines and tissues from patients, and its expression was closely associated with tumor size, lymph node metastasis, and TNM stage. In vitro and in vivo experiments showed that ITGA5 silencing resulted in the inhibition of proliferation, invasion, migration, and graft growth of gastric cancer cells; conversely, the overexpression resulted in the promotion of these cell functions. Our results finally showed that the effect of ITGA5 on proliferation, invasion, and migration of gastric cancer cells was performed through the activation of the FAK/AKT pathway.

Conclusions

ITGA5 promotes proliferation, invasion, and migration of gastric cancer cells through the activation of FAK/AKT signaling pathway, suggesting that ITGA5 may be potentially considered as a new target in gastric cancer therapy.

Lysosomal protein transmembrane 5 promotes lung-specific metastasis by regulating BMPR1A lysosomal degradation

Organotropism during cancer metastasis occurs frequently but the underlying mechanism remains poorly understood. Here, we show that lysosomal protein transmembrane 5 (LAPTM5) promotes lung-specific metastasis in renal cancer. LAPTM5 sustains self-renewal and cancer stem cell-like traits of renal cancer cells by blocking the function of lung-derived bone morphogenetic proteins (BMPs). Mechanistic investigations showed that LAPTM5 recruits WWP2, which binds to the BMP receptor BMPR1A and mediates its lysosomal sorting, ubiquitination and ultimate degradation. BMPR1A expression was restored by the lysosomal inhibitor chloroquine. LAPTM5 expression could also serve as an independent predictor of lung metastasis in renal cancer. Lastly, elevation of LAPTM5 expression in lung metastases is a common phenomenon in multiple cancer types. Our results reveal a molecular mechanism underlying lung-specific metastasis and identify LAPTM5 as a potential therapeutic target for cancers with lung metastasis.

The mechanisms that confer lung-specific metastasis in renal cell carcinomas (RCC) remain to be detailed. Here the authors show that LAPTM5 contributes to lung-specific metastasis of RCCs by suppressing BMP signalling and thus, enhancing self-renewal and cancer stem cell-like traits of RCCs.

Targeting miR-30d reverses pathological cardiac hypertrophy

Background

Pathological cardiac hypertrophy occurs in response to numerous stimuli and precedes heart failure (HF). Therapies that ameliorate pathological cardiac hypertrophy are highly needed.

Methods

The expression level of miR-30d was analyzed in hypertrophy models and serum of patients with chronic heart failure by qRT-PCR. Gain and loss-of-function experiments of miR-30d were performed in vitro. miR-30d gain of function were performed in vivo. Bioinformatics, western blot, luciferase assay, qRT-PCR, and immunofluorescence were performed to examine the molecular mechanisms of miR-30d.

Findings

miR-30d was decreased in both murine and neonatal rat cardiomyocytes (NRCMs) models of hypertrophy. miR-30d overexpression ameliorated phenylephrine (PE) and angiotensin II (Ang II) induced hypertrophy in NRCMs, whereas the opposite phenotype was observed when miR-30d was downregulated. Consistently, the miR-30d transgenic rat was found to protect against isoproterenol (ISO)-induced pathological hypertrophy. Mechanistically, methyltransferase EZH2 could promote H3K27me3 methylation in the promotor region of miR-30d and suppress its expression during the pathological cardiac hypertrophy. miR-30d prevented pathological cardiac hypertrophy via negatively regulating its target genes MAP4K4 and GRP78 and inhibiting pro-hypertrophic nuclear factor of activated T cells (NFAT). Adeno-associated virus (AAV) serotype 9 mediated-miR-30d overexpression exhibited beneficial effects in murine hypertrophic model. Notably, miR-30d was reduced in serum of patients with chronic heart failure and miR-30d overexpression could significantly ameliorate pathological hypertrophy in human embryonic stem cell-derived cardiomyocytes.

Interpretation

Overexpression of miR-30d may be a potential approach to treat pathological cardiac hypertrophy.

Funding

This work was supported by the grants from National Key Research and Development Project (2018YFE0113500 to J Xiao), National Natural Science Foundation of China (82020108002 to J Xiao, 81900359 to J Li), the grant from Science and Technology Commission of Shanghai Municipality (20DZ2255400 and 21XD1421300 to J Xiao, 22010500200 to J Li), Shanghai Sailing Program (19YF1416400 to J Li), the “Dawn” Program of Shanghai Education Commission (19SG34 to J Xiao), the “Chen Guang” project supported by the Shanghai Municipal Education Commission and Shanghai Education Development Foundation (19CG45 to J Li).

The crucial role of epigenetic regulation in breast cancer anti-estrogen resistance: Current findings and future perspectives

Breast cancer (BC) cell de-sensitization to Tamoxifen (TAM) or other selective estrogen receptor (ER) modulators (SERM) is a complex process associated with BC heterogeneity and the transformation of ER signalling. The most influential resistance-related mechanisms include modifications in ER expression and gene regulation patterns. During TAM/SERM treatment, epigenetic mechanisms can effectively silence ER expression and facilitate the development of endocrine resistance. ER status is efficiently regulated by specific epigenetic tools including hypermethylation of CpG islands within ER promoters, increased histone deacetylase activity in the ER promoter, and/or translational repression by miRNAs. Over-methylation of the ER α gene (ESR1) promoter by DNA methyltransferases was associated with poor prognosis and indicated the development of resistance. Moreover, BC progression and spreading were marked by transformed chromatin remodelling, post-translational histone modifications, and expression of specific miRNAs and/or long non-coding RNAs. Therefore, targeted inhibition of histone acetyltransferases (e.g. MYST3), deacetylases (e.g. HDAC1), and/or demethylases (e.g. lysine-specific demethylase LSD1) was shown to recover and increase BC sensitivity to anti-estrogens. Indicated as a powerful molecular instrument, the administration of epigenetic drugs can regain ER expression along with the activation of tumour suppressor genes, which can in turn prevent selection of resistant cells and cancer stem cell survival. This review examines recent advances in the epigenetic regulation of endocrine drug resistance and evaluates novel anti-resistance strategies. Underlying molecular mechanisms of epigenetic regulation will be discussed, emphasising the utilization of epigenetic enzymes and their inhibitors to re-program irresponsive BCs.

HOXA1, a breast cancer oncogene

More than 25 years ago, the first literature records mentioned HOXA1 expression in human breast cancer. A few years later, HOXA1 was confirmed as a proper oncogene in mammary tissue. In the following two decades, molecular data about the mode of action of the HOXA1 protein, the factors contributing to activate and maintain HOXA1 gene expression and the identity of its target genes have accumulated and provide a wider view on the association of this transcription factor to breast oncogenesis. Large-scale transcriptomic data gathered from wide cohorts of patients further allowed refining the relationship between breast cancer type and HOXA1 expression. Several recent reports have reviewed the connection between cancer hallmarks and the biology of HOX genes in general. Here we take HOXA1 as a paradigm and propose an extensive overview of the molecular data centered on this oncoprotein, from what its expression modulators, to the interactors contributing to its oncogenic activities, and to the pathways and genes it controls. The data converge to an intricate picture that answers questions on the multi-modality of its oncogene activities, point towards better understanding of breast cancer aetiology and thereby provides an appraisal for treatment opportunities.

Anti-cancer function of microRNA-30e is mediated by negative regulation of HELLPAR, a noncoding macroRNA, and genes involved in ubiquitination and cell cycle progression in prostate cancer

Prostate cancer (PCa) progression relies on androgen receptor (AR) function, making AR a top candidate for PCa therapy. However, development of drug resistance is common, which eventually leads to development of castration‐resistant PCa. This warrants a better understanding of the pathophysiology of PCa that facilitates the aberrant activation of key signaling pathways including AR. MicroRNAs (miRNAs) function as regulators of cancer progression as they modulate various cellular processes. Here, we demonstrate a multidimensional function of miR‐30e through the regulation of genes involved in various signaling pathways. We noted loss of miR‐30e expression in prostate tumors, which, when restored, led to cell cycle arrest, induction of apoptosis, improved drug sensitivity of PCa cells and reduced tumor progression in xenograft models. We show that experimental upregulation of miR‐30e reduces expression of mRNAs including AR, FBXO45, SRSF7 and MYBL2 and a novel long noncoding RNA (lncRNA) HELLPAR, which are involved in cell cycle, apoptosis and ubiquitination, and the effects could be rescued by inhibition of miR‐30e expression. RNA immunoprecipitation analysis confirmed direct interactions between miR‐30e and its RNA targets. We noted a newly identified reciprocal relationship between miR‐30e and HELLPAR, as inhibition of HELLPAR improved stabilization of miR‐30e. Transcriptome profiling and quantitative real‐time PCR (qRT‐PCR) validation of miR‐30e‐expressing PCa cells showed differential expression of genes involved in cell cycle progression, apoptosis and ubiquitination, which supports our in vitro study. This study demonstrates an integrated function of miR‐30e on dysregulation of miRNA/lncRNA/mRNA axes that may have diagnostic and therapeutic significance in aggressive PCa.

Regulation of osteoclast-mediated bone resorption by microRNA

Osteoclast-mediated bone resorption is responsible for bone metabolic diseases, negatively impacting people's health and life. It has been demonstrated that microRNA influences the differentiation of osteoclasts by regulating the signaling pathways during osteoclast-mediated bone resorption. So far, the involved mechanisms have not been fully elucidated. This review introduced the pathways involved in osteoclastogenesis and summarized the related microRNAs binding to their specific targets to mediate the downstream pathways in osteoclast-mediated bone resorption. We also discuss the clinical potential of targeting microRNAs to treat osteoclast-mediated bone resorption as well as the challenges of avoiding potential side effects and producing efficient delivery methods.

Isolation of a Human Betaretrovirus from Patients with Primary Biliary Cholangitis

A human betaretrovirus (HBRV) has been linked with the autoimmune liver disease, primary biliary cholangitis (PBC), and various cancers, including breast cancer and lymphoma. HBRV is closely related to the mouse mammary tumor virus, and represents the only exogenous betaretrovirus characterized in humans to date. Evidence of infection in patients with PBC has been demonstrated through the identification of proviral integration sites in lymphoid tissue, the major reservoir of infection, as well as biliary epithelium, which is the site of the disease process. Accordingly, we tested the hypothesis that patients with PBC harbor a transmissible betaretrovirus by co-cultivation of PBC patients’ lymph node homogenates with the HS578T breast cancer line. Because of the low level of HBRV replication, betaretrovirus producing cells were subcloned to optimize viral isolation and production. Evidence of infection was provided by electron microscopy, RT-PCR, in situ hybridization, cloning of the HBRV proviral genome and demonstration of more than 3400 integration sites. Further evidence of viral transmissibility was demonstrated by infection of biliary epithelial cells. While HBRV did not show a preference for integration proximal to specific genomic features, analyses of common insertion sites revealed evidence of integration proximal to cancer associated genes. These studies demonstrate the isolation of HBRV with features similar to mouse mammary tumor virus and confirm that patients with PBC display evidence of a transmissible viral infection.

Extracellular Vesicle-Packaged CDH11 and ITGA5 Induce the Premetastatic Niche for Bone Colonization of Breast Cancer Cells

Although most breast cancer metastases in bone cause osteolytic lesions, the osteogenic niche has commonly been described as an initiator of early-stage bone colonization of disseminated cancer cells. Tumor cell-derived extracellular vesicles (EV) have been shown to determine the organotropism of cancer cells by transferring their cargo, such as nucleic acids and proteins, to resident cells at future metastatic sites and preparing a favorable premetastatic niche. Runt-related transcription factor 2 (RUNX2) and its regulated genes have been shown to facilitate the acquisition of osteomimetic features and to enhance the bone metastatic potential of breast cancer cells. In this study, we present in vivo and in vitro evidence to clarify the role of EVs released by breast cancer cells with high RUNX2 expression in the education of osteoblasts to form an osteogenic premetastatic niche. Furthermore, different extracellular vesicular proteins were identified that mediate events subsequent to the specific recognition of tumor-derived EVs by osteoblasts via cadherin 11 (CDH11) and the induction of the osteogenic premetastatic niche by integrin α5 (ITGA5). CDH11high/ITGA5high EVs were demonstrated to be responsible for the formation of a premetastatic niche that facilitates RUNX2 high-expressing breast cancer cell colonization in bone, revealing a potential EV-based premetastatic niche blockage strategy.

SIGNIFICANCE

This study provides mechanistic insights into the generation of an osteogenic premetastatic niche by breast cancer-derived EVs and identifies potential EV-derived diagnostic biomarkers and targets for breast cancer bone metastasis.

Expression Profiling of Selected Immune Genes and Trabecular Microarchitecture in Breast Cancer Skeletal Metastases Model: Effect of α-Tocopherol Acetate Supplementation

Breast cancer bone metastases (BCBM) result in serious skeletal morbidity. Although there have been important advances in cancer treatment methods such as surgery and chemotherapy, the complementary treatments, such as α-tocopherol acetate (ATA), still remain of key role via complementary and/or synergistic effects. The aim of this work was to study immune response in a rat model of BCBM due to Walker 256/B cells inoculation and the effect of ATA alone. Compared to the control group (CTRL), rat injected with Walker 256/B cells (5 × 10⁴) in the medullar cavity (W256 group) showed osteolytic damages with marked tumor osteolysis of both cancellous and trabecular bone as assessed by X-ray radiology, micro-computed tomography, and histology. Rats inoculated with Walker 256/B cells and treated with ATA (45 mg/kg BW, W256ATA group) presented marked less tumor osteolysis, less disturbance of Tb.Th and Tb.Sp associated with conversion of rods into plates, and increased structure model index and trabecular pattern factor (Tb.Pf). Elsewhere, 3D frequency distributions of Tb.Th and Tb.Sp were highly disturbed in metastatic W256 rats. Overexpression of some genes commonly associated with cancer and metastatic proliferation: COX-2, TNF-α, and pro-inflammatory interleukins 1 and 6 was outlined. ATA alleviated most of the Walker 256/B cells-induced microarchitectural changes in the target parameters without turning back to normal levels. Likewise, it alleviates the BCSM-induced overexpression of COX-2, TNF-α, IL-1, and IL-6. In silico approach showed that ATA bound these proteins with high affinities, which satisfactory explain its beneficial effects. In conclusion, BCBM is associated with bone microarchitectural disorders and an immune response characterized by an overexpression of some key role genes in cancer proliferation and invasion. ATA exerted favorable effects on trabecular bone distribution and morphology, which may involve the COX-2, TNF-α, and ILs pathways.

Multifunctional regulatory protein connective tissue growth factor (CTGF): A potential therapeutic target for diverse diseases

Connective tissue growth factor (CTGF), a multifunctional protein of the CCN family, regulates cell proliferation, differentiation, adhesion, and a variety of other biological processes. It is involved in the disease-related pathways such as the Hippo pathway, p53 and nuclear factor kappa-B (NF-κB) pathways and thus contributes to the developments of inflammation, fibrosis, cancer and other diseases as a downstream effector. Therefore, CTGF might be a potential therapeutic target for treating various diseases. In recent years, the research on the potential of CTGF in the treatment of diseases has also been paid more attention. Several drugs targeting CTGF (monoclonal antibodies FG3149 and FG3019) are being assessed by clinical or preclinical trials and have shown promising outcomes. In this review, the cellular events regulated by CTGF, and the relationships between CTGF and pathogenesis of diseases are systematically summarized. In addition, we highlight the current researches, focusing on the preclinical and clinical trials concerned with CTGF as the therapeutic target.

miRNA-guided reprogramming of glucose and glutamine metabolism and its impact on cell adhesion/migration during solid tumor progression

MicroRNAs (miRNAs) are small, non-coding RNAs about 22 nucleotides in length that regulate the expression of target genes post-transcriptionally, and are highly involved in cancer progression. They are able to impact a variety of cell processes such as proliferation, apoptosis and differentiation and can consequently control tumor initiation, tumor progression and metastasis formation. miRNAs can regulate, at the same time, metabolic gene expression which, in turn, influences relevant traits of malignancy such as cell adhesion, migration and invasion. Since the interaction between metabolism and adhesion or cell movement has not, to date, been well understood, in this review, we will specifically focus on miRNA alterations that can interfere with some metabolic processes leading to the modulation of cancer cell movement. In addition, we will analyze the signaling pathways connecting metabolism and adhesion/migration, alterations that often affect cancer cell dissemination and metastasis formation.

Breast Cancer Subtype-Specific miRNAs: Networks, Impacts, and the Potential for Intervention

The regulatory and functional roles of non-coding RNAs are increasingly demonstrated as critical in cancer. Among non-coding RNAs, microRNAs (miRNAs) are the most well-studied with direct regulation of biological signals through post-transcriptional repression of mRNAs. Like the transcriptome, which varies between tissue type and disease condition, the miRNA landscape is also similarly altered and shows disease-specific changes. The importance of individual tumor-promoting or suppressing miRNAs is well documented in breast cancer; however, the implications of miRNA networks is less defined. Some evidence suggests that breast cancer subtype-specific cellular effects are influenced by distinct miRNAs and a comprehensive network of subtype-specific miRNAs and mRNAs would allow us to better understand breast cancer signaling. In this review, we discuss the altered miRNA landscape in the context of breast cancer and propose that breast cancer subtypes have distinct miRNA dysregulation. Further, given that miRNAs can be used as diagnostic and/or prognostic biomarkers, their impact as novel targets for subtype-specific therapy is also possible and suggest important implications for subtype-specific miRNAs.

miR-30b-5p inhibits osteoblast differentiation through targeting BCL6

Human bone marrow mesenchymal stem cells (hBMSCs) are attractive candidates for new therapies to improve bone regeneration and repair. This study was to identify the function of the miR-30b-5p/BCL6 axis in osteogenic differentiation of hBMSCs. Realtime-quantitative PCR (RT-qPCR) and Western blotting were used to measure the relative expression of ALP, OCN, RUNX2, miR-30b-5p, and BCL6 during osteogenic differentiation of hBMSCs. The relationship between miR-30b-5p and BCL6 in hBMSCs was identified using dual-luciferase reporter system and RNA pull-down assay. Alizarin red S staining (ARS) was used to detect the calcium nodules in hBMSCs. We found that the expression of miR-30b-5p was downregulated, whereas that of BCL6 was upregulated during osteogenic differentiation of hBMSCs. Downregulating miR-30b-5p enhanced the expression of OCN, RUNX2, and ALP, and promoted calcium deposition. Conversely, transfection with si-BCL6 had the opposite effect that it inhibited osteogenic differentiation. However, the inhibitory effect of si-BCL6 was abrogated by miR-30b-5p inhibitor. miR-30b-5p inhibits the osteogenic differentiation of hBMSCs by targeting BCL6.