Timp3 deficient mice show resistance to developing breast cancer

The TIMP protein family: diverse roles in pathophysiology

The tissue inhibitors of matrix metalloproteinases (TIMPs) are a family of four matrisome proteins classically defined by their roles as the primary endogenous inhibitors of metalloproteinases (MPs). Their functions however are not limited to MP inhibition, with each family member harboring numerous MP-independent biological functions that play key roles in processes such as inflammation and apoptosis. Because of these multifaceted functions, TIMPs have been cited in diverse pathophysiological contexts. Herein, we provide a comprehensive overview of the MP-dependent and -independent roles of TIMPs across a range of pathological conditions. The potential therapeutic and biomarker applications of TIMPs in these disease contexts are also considered, highlighting the biomedical promise of this complex and often misunderstood protein family.

Proteins Found in the Triple-Negative Breast Cancer Secretome and Their Therapeutic Potential

The cancer secretome comprises factors secreted by tumors, including cytokines, growth factors, proteins from the extracellular matrix (ECM), proteases and protease inhibitors, membrane and extracellular vesicle proteins, peptide hormones, and metabolic proteins. Secreted proteins provide an avenue for communication with other tumor cells and stromal cells, and these in turn promote tumor growth and progression. Breast cancer is the most commonly diagnosed cancer in women in the US and worldwide. Triple-negative breast cancer (TNBC) is characterized by its aggressiveness and its lack of expression of the estrogen receptor (ER), progesterone receptor (PR), and HER2, making it unable to be treated with therapies targeting these protein markers, and leaving patients to rely on standard chemotherapy. In order to develop more effective therapies against TNBC, researchers are searching for targetable molecules specific to TNBC. Proteins in the TNBC secretome are involved in wide-ranging cancer-promoting processes, including tumor growth, angiogenesis, inflammation, the EMT, drug resistance, invasion, and development of the premetastatic niche. In this review, we catalog the currently known proteins in the secretome of TNBC tumors and correlate these secreted molecules with potential therapeutic opportunities to facilitate translational research.

Matrix metalloproteinases as therapeutic targets in breast cancer

Matrix metalloproteinases (MMPs) are the most prominent proteinases involved in tumorigenesis. They were initially recognized to promote tumor progression by remodeling the extracellular matrix through their proteolytic activity. However, accumulating evidence has revealed that some MMPs have protective roles in cancer progression, and the same MMP can exert opposing roles depending on the cell type in which it is expressed or the stage of cancer. Moreover, studies have shown that MMPs are involved in cancer progression through their roles in other biological processes such as cell signaling and immune regulation, independent of their catalytic activity. Despite the prognostic significance of tumoral or stromal expression of MMPs in breast cancer, their roles and molecular mechanisms in breast cancer progression remain unclear. As the failures of early clinical trials with broad-spectrum MMP inhibitors were mainly due to a lack of drug specificity, substantial efforts have been made to develop highly selective MMP inhibitors. Some recently developed MMP inhibitory monoclonal antibodies demonstrated promising anti-tumor effects in preclinical models of breast cancer. Importantly, anti-tumor effects of these antibodies were associated with the modulation of tumor immune microenvironment, suggesting that the use of MMP inhibitors in combination with immunotherapy can improve the efficacy of immunotherapy in HER2-positive or triple-negative breast cancer. In this review, the current understanding of the roles of tumoral or stromal MMPs in breast cancer is summarized, and recent advances in the development of highly selective MMP inhibitors are discussed.

MicroRNA-30d target TIMP3 induces pituitary tumor cell growth and invasion

BACKGROUND

As one of the most common intracranial tumors, pituitary adenomas, especially the Cushing's disease subtype, have been studied for many years. However, at present, effective methods for the early diagnosis of pituitary adenomas are very limited, especially for subtypes such as Cushing's disease. Therefore, it is of urgent importance to find effective molecular targets to develop new diagnostic and therapeutic methods for pituitary adenomas.

METHODS

We showed the abnormally high expression of miR-30d in pituitary adenomas by analyzing data in the Gene Expression Omnibus (GEO) database and revealed a novel molecular mechanism of miR-30d in regulating the proliferation and invasion of a pituitary adenoma cell line (AtT-20). Cell culture and transfection, and RNA interference (RNAi) were used to treat AtT-20 cells to test the effects of miR-30d and TIMP3 on cells. Quantitative polymerase chain reaction (qPCR) was used to determine the messenger RNA (mRNA) expressions. We used 3-(4,5-diphenyltetrazolium bromide) (MTT) to determine cell viabilities. An invasion assay was performed using Transwell chambers. Luciferase activity was tested with a dual-luciferase assay.

RESULTS

We found that the expression of miR-30d in pituitary adenoma was higher than that in normal pituitary tissues. It was revealed that miR-30d promoted the proliferation and invasion of AtT-20 cells by inhibiting the expression of TIMP3. In the above process, miR-30d could bind to the 3'-untranslated region (3'-UTR) of TIMP3 mRNA.

CONCLUSIONS

The mir-30d/TIMP3 signaling pathway plays an important regulatory role in pituitary adenomas. These new discoveries may reveal more functions of miR-30d and lay the foundation for future clinical development of new drug targets.

miR-4431 targets TRIP10/PRKD1 and impairs glucose metabolism

Aim/Introduction

Obesity is considered an important risk factor for many metabolic disorders, especially type 2 diabetes mellitus, and microRNAs (miRNAs) play a vital role in the development of type 2 diabetes mellitus. Therefore, we conducted this study to investigate the role of miR‐4431 in the obesity‐associated pathobiology of type 2 diabetes mellitus.

Materials and methods

Subjects were divided into normal control (n = 36), obese (n = 36), and type 2 diabetes mellitus (n = 12) groups, and serum miR‐4431 levels were analyzed. Adenovirus‐vectored miR‐4431 mimic or sponge was intraperitoneally injected into the normal diet group and the high‐fat diet group (HFD) mice to investigate glucose tolerance, insulin sensitivity, and lipid levels. The downstream target genes of miR‐4431 were predicted using bioinformatics, and they were verified in vitro.

Results

Serum miR‐4431 levels were significantly high in obese and type 2 diabetes mellitus individuals, and positively correlated with the body mass index and fasting plasma glucose levels. In HFD mice, miR‐4431 levels in the serum, white adipose tissue, and liver were significantly increased. Moreover, miR‐4431 impaired glucose tolerance, insulin sensitivity, and lipid metabolism in mice. Bioinformatic prediction suggested that TRIP10 and PRKD1 could be the downstream target genes of miR‐4431. The HFD mice showed a remarkable reduction in the mRNA levels of TRIP10 and PRKD1 in the liver, which were countered by blocking miR‐4431. In HepG2 and L02 cells, miR‐4431 could downregulate TRIP10 and PRKD1 while blocking glucose uptake. The luciferase reporter assay showed that miR‐4431 could bind TRIP10 and PRKD1 3′‐UTR.

Conclusion

miR‐4431 targets TRIP10/PRKD1 and impairs glucose metabolism.

Extracellular Vesicle Molecular Signatures Characterize Metastatic Dynamicity in Ovarian Cancer

BACKGROUND

Late-stage diagnosis of ovarian cancer, a disease that originates in the ovaries and spreads to the peritoneal cavity, lowers 5-year survival rate from 90% to 30%. Early screening tools that can: i) detect with high specificity and sensitivity before conventional tools such as transvaginal ultrasound and CA-125, ii) use non-invasive sampling methods and iii) longitudinally significantly increase survival rates in ovarian cancer are needed. Studies that employ blood-based screening tools using circulating tumor-cells, -DNA, and most recently tumor-derived small extracellular vesicles (sEVs) have shown promise in non-invasive detection of cancer before standard of care. Our findings in this study show the promise of a sEV-derived signature as a non-invasive longitudinal screening tool in ovarian cancer.

METHODS

Human serum samples as well as plasma and ascites from a mouse model of ovarian cancer were collected at various disease stages. Small extracellular vesicles (sEVs) were extracted using a commercially available kit. RNA was isolated from lysed sEVs, and quantitative RT-PCR was performed to identify specific metastatic gene expression.

CONCLUSION

This paper highlights the potential of sEVs in monitoring ovarian cancer progression and metastatic development. We identified a 7-gene panel in sEVs derived from plasma, serum, and ascites that overlapped with an established metastatic ovarian carcinoma signature. We found the 7-gene panel to be differentially expressed with tumor development and metastatic spread in a mouse model of ovarian cancer. The most notable finding was a significant change in the ascites-derived sEV gene signature that overlapped with that of the plasma-derived sEV signature at varying stages of disease progression. While there were quantifiable changes in genes from the 7-gene panel in serum-derived sEVs from ovarian cancer patients, we were unable to establish a definitive signature due to low sample number. Taken together our findings show that differential expression of metastatic genes derived from circulating sEVs present a minimally invasive screening tool for ovarian cancer detection and longitudinal monitoring of molecular changes associated with progression and metastatic spread.

The prognostic and diagnostic value of tissue inhibitor of metalloproteinases gene family and potential function in gastric cancer

Background: Tissue inhibitor of metalloproteinases (TIMP) gene family, including TIMP1, TIMP2, TIMP3 and TIMP4, was found to be correlated with serval cancers. Still the diagnostic and prognostic study of it in gastric cancer (GC) have few reports.

Methods and materials: In this study, the gene expression and clinical data were acquired from the Cancer Gene Atlas (TCGA), function enrichment was used by several databases for verifying known function. Operating characteristic (ROC) curves with area under the curve (AUC) used to assess diagnostic value. Survival analysis and joint-effects survival analysis was performed by the Kaplan-Meier curve. The results were adjusted by cox-regression model. Nomogram is used to directly predict the survival rate for individual GC patient. The potential mechanism for diagnostic and prognostic value was assessed by gene set enrichment analysis (GSEA). Further functions of gene were verified by cell proliferation, migration and invasion assays in human gastric cancer cell line.

Results:TIMP1 was expressed in GC tissue was higher than normal gastric tissue. TIMP3 and TIMP4 have expressed in normal gastric tissue were higher than GC tissue. TIMP1, TIMP3 and TIMP4 have potential diagnostic value (AUC=0.842, 0.729, 0.786 respectively; all P<0.01). Low expression of TIMP2 and TIMP3 associated with favorable overall survival (all P<0.05). TIMP2 and TIMP3, which had significantly affection of prognosis were found having some function such as tRNA processing, cell cycle pathway ncRNA processing. The silencing of TIMP3 could inhibit the migration and invasion of gastric cancer cell.

Conclusion: We analyzed the TIMP gene family in GC, and the prognostic and diagnostic value. TIMP1 and TIMP2 could be used as diagnostic biomarkers in GC. TIMP2 and TIMP3 could be used as potential biomarkers for GC's prognosis.

Long non-coding RNA ROR recruits histone transmethylase MLL1 to up-regulate TIMP3 expression and promote breast cancer progression

Background

As a significant cause of cancer deaths worldwide, breast cancer continues to be a troublesome malignancy. Long non-coding RNAs (lncRNAs) have been implicated in the development of breast cancer. Abnormal methylation has been associated with unfavorable breast cancer prognosis. Herein, the current study aimed to elucidate the role of lncRNA ROR in breast cancer.

Methods

RT-qPCR was performed to determine whether lncRNA ROR was highly expressed in breast cancer tissues, while lncRNA ROR expression was detected in both the nuclear and cytoplasm of breast cancer cells. MCF-7 cells were subsequently introduced with oe-lncRNA ROR, sh-lncRNA ROR to explore the effects of lncRNA ROR on cell proliferation, invasion and apoptosis.

Results

RIP, RNA pull-down and ChIP assays provided evidence suggesting that lncRNA ROR recruited transmethylase MLL1 to promote H3K4 trimethylation that enhanced TIMP3 transcription. The rescue experiments demonstrated that lncRNA ROR knockdown could inhibit the progression of breast cancer via the downregulation of TIMP3. Finally, the in vivo experiment findings consistently highlighted the suppressive effects of lncRNA ROR silencing on tumor growth.

Conclusion

Taken together, our study demonstrates that silencing of lncRNA ROR inhibits breast cancer progression via repression of transmethylase MLL1 and TIMP3, emphasizing the potential of lncRNA ROR as a novel target against breast cancer.

Pubertal mammary gland development is a key determinant of adult mammographic density

Mammographic density refers to the radiological appearance of fibroglandular and adipose tissue on a mammogram of the breast. Women with relatively high mammographic density for their age and body mass index are at significantly higher risk for breast cancer. The association between mammographic density and breast cancer risk is well-established, however the molecular and cellular events that lead to the development of high mammographic density are yet to be elucidated. Puberty is a critical time for breast development, where endocrine and paracrine signalling drive development of the mammary gland epithelium, stroma, and adipose tissue. As the relative abundance of these cell types determines the radiological appearance of the adult breast, puberty should be considered as a key developmental stage in the establishment of mammographic density. Epidemiological studies have pointed to the significance of pubertal adipose tissue deposition, as well as timing of menarche and thelarche, on adult mammographic density and breast cancer risk. Activation of hypothalamic-pituitary axes during puberty combined with genetic and epigenetic molecular determinants, together with stromal fibroblasts, extracellular matrix, and immune signalling factors in the mammary gland, act in concert to drive breast development and the relative abundance of different cell types in the adult breast. Here, we discuss the key cellular and molecular mechanisms through which pubertal mammary gland development may affect adult mammographic density and cancer risk.

Adipose monocyte chemotactic protein-1 deficiency reduces high-fat diet-enhanced mammary tumorigenesis in MMTV-PyMT mice

Monocyte chemotactic protein-1 (MCP-1) is an adipokine with demonstrated carcinogenic potential. However, there is a lack of evidence whether adipose-produced MCP-1 contributes to breast cancer. We tested the hypothesis that adipose-produced MCP-1 contributes to mammary tumorigenesis in this study. In a breast cancer model of mouse mammary tumor virus-polyomavirus middle T-antigen (MMTV-PyMT), mice with or without adipose MCP-1 knockout [designated as Mcp-1-/- or wild-type (WT)] were fed the standard AIN93G diet (16% of energy from soybean oil) or a high-fat diet (HFD, 45% of energy from soybean oil). Adipose MCP-1 knockout reduced Mcp-1 expression in adipose tissue and concentrations of MCP-1 in plasma. Mcp-1-/- mice fed the HFD had less body fat than their WT counterparts. Adipose MCP-1 knockout attenuated HFD-enhanced mammary tumorigenesis, evidenced by lower mammary tumor volume. Furthermore, Mcp-1-/- mice, regardless of diet, had a longer tumor latency and less tumor weight than WT mice. When fed the HFD, Mcp-1-/- mice, compared to WT mice, exhibited lower concentrations of insulin, leptin, resistin, vascular endothelial growth factor and hepatic growth factor in plasma. In summary, adipose MCP-1 deficiency attenuated HFD-enhanced MMTV-PyMT mammary tumorigenesis. This attenuation can be attributed to less body adiposity, improvement in insulin sensitivity and down-regulation in protumorigenic inflammation cytokines and angiogenic factors in Mcp-1-/- mice. It concludes that adipose-produced MCP-1 contributes to mammary tumorigenesis in the MMTV-PyMT mouse model.

TIMP-3 as a therapeutic target for cancer

Tissue inhibitor of metalloproteinase-3 (TIMP-3), a secreted glycoprotein, plays an important role in carcinogenesis. It can bind to many proteinases to suppress their activity and thus protect the extracellular matrix from degradation. TIMP-3 may have many anticancer properties, including apoptosis induction and antiproliferative, antiangiogenic, and antimetastatic activities. This review summarizes the structure, proteinase inhibition ability, genetic and epigenetic regulation, cancer therapy potential, and contribution to cancer development of TIMP-3. Furthermore, in this review we discuss its potential as a biomarker for predicting cancer progression and the current state of drugs that target TIMP-3, either alone or in combination with clinical treatment. In conclusion, TIMP-3 can be a biomarker of cancer and a potential target for cancer therapy. This review article can serve as a basis to understand how to modulate TIMP-3 levels as a drug target of cancers.

High olive oil diets enhance cervical tumour growth in mice: transcriptome analysis for potential candidate genes and pathways

BACKGROUND

Numerous epidemiologic studies have found a close association between obesity and cancer. Dietary fat is a fundamental contributor to obesity and is a risk factor for cancer. Thus far, the impact of dietary olive oil on cancer development remains inconclusive, and little is known about its underlying mechanisms.

METHODS

Nude mouse xenograft models were used to examine the effects of high olive oil diet feeding on cervical cancer (CC) development and progression. Cell proliferation, migration and invasion were observed by the methods of EdU incorporation, Wound healing and Transwell assay, separately. RNA-sequencing technology and comprehensive bioinformatics analyses were used to elucidate the molecular processes regulated by dietary fat. Differentially expressed genes (DEGs) were identified and were functionally analyzed by Gene Ontology (GO), Kyoto Enrichment of Genes and Genomes (KEGG). Then, protein-protein interaction (PPI) network and sub-PPI network analyses were conducted using the STRING database and Cytoscape software.

RESULTS

A high olive oil diet aggravated tumourigenesis in an experimental xenograft model of CC. Oleic acid, the main ingredient of olive oil, promoted cell growth and migration in vitro. Transcriptome sequencing analysis of xenograft tumour tissues was then performed to elucidate the regulation of molecular events regulated by dietary fat. Dietary olive oil induced 648 DEGs, comprising 155 up-regulated DEGs and 493 down-regulated DEGs. GO and pathway enrichment analysis revealed that some of the DEGs including EGR1 and FOXN2 were involved in the transcription regulation and others, including TGFB2 and COL4A3 in cell proliferation. The 15 most strongly associated DEGs were selected from the PPI network and hub genes including JUN, TIMP3, OAS1, OASL and EGR1 were confirmed by real-time quantitative PCR analysis.

CONCLUSIONS

Our study suggests that a high olive oil diet aggravates CC progression in vivo and in vitro. We provide clues to build a potential link between dietary fat and cancerogenesis and identify areas requiring further investigation.

Tissue inhibitor of the metalloproteinases-3 gene polymorphisms and carotid plaque susceptibility in the Han Chinese population

Tissue inhibitor of metalloproteinases (TIMPs) are endogenous inhibitors of matrix metalloproteinases that are involved in normal cellular processes and in the development and progression of atherosclerosis. Our purpose was to evaluate the polymorphisms of the TIMP-3 genes for their associations with carotid plaques or with serum protein levels in the Han Chinese population. Two promoter variants, -915A/G (rs2234921) and -1296T/C (rs9619311), were genotyped in 548 subjects with no plaques, 462 subjects with echogenic plaques, and 427 subjects with mixture plaques. The serum TIMP-3 levels were measured using an enzyme-linked immunosorbent assay (ELISA). There was a strong linkage disequilibrium between -1296T/C and -915A/G (D' = 1.0, r² = 0.991). The individuals with the genotype (TC+CC) were 1.8 times more likely to have mixture plaques than the individuals with the TT genotype (P = 0.001, OR: 1.836, 95%CI: 1.269-2.665). The frequency of the C allele in the mixture plaque group was significantly higher than in the no plaque group (P = 0.009, CI: 1.119-2.187). We observed a significant elevation of the TIMP-3 levels in the serum of patients affected with mixture plaques compared to those with no plaques (P = 0.013). The current data suggest that genetic variation in the TIMP-3 genes may contribute to individual differences in mixture plaque susceptibility in the Han Chinese population.

Deletion of the murine ortholog of the 8q24 gene desert has anti-cancer effects in transgenic mammary cancer models

Background

The gene desert on human chromosomal band 8q24 harbors multiple genetic variants associated with common cancers, including breast cancer. The locus, including the gene desert and its flanking genes, MYC, PVT1 and FAM84B, is also frequently amplified in human breast cancer. We generated a megadeletion (MD) mouse model lacking 430-Kb of sequence orthologous to the breast cancer-associated region in the gene desert. The goals were to examine the effect of the deletion on mammary cancer development and on transcript level regulation of the candidate genes within the locus.

Methods

The MD allele was engineered using the MICER system in embryonic stem cells and bred onto 3 well-characterized transgenic models for breast cancer, namely MMTV-PyVT, MMTV-neu and C3(1)-TAg. Mammary tumor growth, latency, multiplicity and metastasis were compared between homozygous MD and wild type mice carrying the transgenes. A reciprocal mammary gland transplantation assay was conducted to distinguish mammary cell-autonomous from non-mammary cell-autonomous anti-cancer effects. Gene expression analysis was done using quantitative real-time PCR. Chromatin interactions were evaluated by 3C. Gene-specific patient outcome data were analysed using the METABRIC and TCGA data sets through the cBioPortal website.

Results

Mice homozygous for the MD allele are viable, fertile, lactate sufficiently to nourish their pups, but maintain a 10% lower body weight mainly due to decreased adiposity. The deletion interferes with mammary tumorigenesis in mouse models for luminal and basal breast cancer. In the MMTV-PyVT model the mammary cancer-reducing effects of the allele are mammary cell-autonomous. We found organ-specific effects on transcript level regulation, with Myc and Fam84b being downregulated in mammary gland, prostate and mammary tumor samples. Through analysis using the METABRIC and TCGA datasets, we provide evidence that MYC and FAM84B are frequently co-amplified in breast cancer, but in contrast with MYC, FAM84B is frequently overexpressed in the luminal subtype, whereas MYC activity affect basal breast cancer outcomes.

Conclusion

Deletion of a breast cancer-associated non-protein coding region affects mammary cancer development in 3 transgenic mouse models. We propose Myc as a candidate susceptibility gene, regulated by the gene desert locus, and a potential role for Fam84b in modifying breast cancer development.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-5109-8) contains supplementary material, which is available to authorized users.

Aging Mouse Models Reveal Complex Tumor-Microenvironment Interactions in Cancer Progression

Mouse models and genetically engineered mouse models (GEMM) are essential experimental tools for the understanding molecular mechanisms within complex biological systems. GEMM are especially useful for inferencing phenocopy information to genetic human diseases such as breast cancer. Human breast cancer modeling in mice most commonly employs mammary epithelial-specific promoters to investigate gene function(s) and, in particular, putative oncogenes. Models are specifically useful in the mammary epithelial cell in the context of the complete mammary gland environment. Gene targeted knockout mice including conditional targeting to specific mammary cells can reveal developmental defects in mammary organogenesis and demonstrate the importance of putative tumor suppressor genes. Some of these models demonstrate a non-traditional type of tumor suppression which involves interplay between the tumor susceptible cell and its host/environment. These GEMM help to reveal the processes of cancer progression beyond those intrinsic to cancer cells. Furthermore, the, analysis of mouse models requires appropriate consideration of mouse strain, background, and environmental factors. In this review, we compare aging-related factors in mouse models for breast cancer. We introduce databases of GEMM attributes and colony functional variations.

Hepatocyte specific TIMP3 expression prevents diet dependent fatty liver disease and hepatocellular carcinoma

Non-alcoholic fatty liver disease (NAFLD) encompasses a broad spectrum of conditions, ranging from non-progressive bland steatosis to hepatocarcinoma. Tissue inhibitor of metalloproteinase 3 (Timp3) has a role in the pathogenesis of fatty liver disease associated with obesity and is silenced during metabolic disorders and liver cancer. We generated an hepatocyte-specific TIMP3 'gain-of-function' mouse model under the control of the Albumin promoter (AlbT3) and investigated its effects during high-fat diet (HFD). After 16 weeks of HFD, TIMP3 overexpression significantly improved glucose metabolism, hepatic fatty acid oxidation and cholesterol homeostasis. In AlbT3 mice CYP7A1, MDR3 and MRP2 gene expressions were observed, consistent with higher bile acid synthesis and export. Next, to evaluate the role of A Disintegrin and Metalloproteinase 17 (ADAM17), a crucial target of TIMP3, in these processes, we created mice deficient in Adam17 specifically in hepatocyte (A17LKO) or in myeloid lineage (A17MKO), founding that only A17LKO showed improvement in liver steatosis induced by HFD. Moreover, both, AlbT3 and A17LKO significantly reduced diethylnitrosamine-initiated, HFD-promoted hepatic tumorigenesis assessed by tumor multiplicity and total tumor area. Taken together, these data indicate that hepatic TIMP3 can slow progression of NAFLD, and tumorigenesis, at least in part, through the regulation of ADAM17 activity.

TIMPs: versatile extracellular regulators in cancer

A compelling long-term goal of cancer biology is to understand the crucial players during tumorigenesis in order to develop new interventions. Here, we review how the four non-redundant tissue inhibitors of metalloproteinases (TIMPs) regulate the pericellular proteolysis of a vast range of matrix and cell surface proteins, generating simultaneous effects on tumour architecture and cell signalling. Experimental studies demonstrate the contribution of TIMPs to the majority of cancer hallmarks, and human cancers invariably show TIMP deregulation in the tumour or stroma. Of the four TIMPs, TIMP1 overexpression or TIMP3 silencing is consistently associated with cancer progression or poor patient prognosis. Future efforts will align mouse model systems with changes in TIMPs in patients, will delineate protease-independent TIMP function, will pinpoint therapeutic targets within the TIMP-metalloproteinase-substrate network and will use TIMPs in liquid biopsy samples as biomarkers for cancer prognosis.

Exploration of the regulatory effect of miR-21 on breast cancer cell line proliferation and invasion as well as the downstream target genes

OBJECTIVE

To study the regulatory effects of miR-21 on breast cancer cell line proliferation and invasion as well as the downstream target genes.

METHODS

Breast cancer cell lines MCF-7 were cultured and transfected with miR-21 mimics and the corresponding negative control mimics (NC mimics), and then MTS kits were used to detect cell viability. Transwell experiment was used to detect cell invasion ability, and fluorescence quantitative PCR was used to detect the expression of proliferation and invasion-related genes in cells.

RESULTS

24 h after transfection of miR-21 mimics and NC mimics, cell OD value and the number of invasive cells of miR-21 group were significantly higher than those of NC group, and mRNA contents of PDCD-4, FasL, PTEN, RhoB, Maspin, TIMP3 and RECK in cells were significantly lower than those of NC group.

CONCLUSION

miR-21 can promote the proliferation and invasion of breast cancer cell lines, and its downstream target genes include PDCD-4, FasL, PTEN, RhoB, Maspin, TIMP3 and RECK.