Tissue inhibitor of metalloproteinase-3 (TIMP3) expression decreases during melanoma progression and inhibits melanoma cell migration

Targeting anoikis resistance as a strategy for cancer therapy

Anoikis, known as matrix detachment-induced apoptosis or detachment-induced cell death, is crucial for tissue development and homeostasis. Cancer cells develop means to evade anoikis, e.g. anoikis resistance, thereby allowing for cells to survive under anchorage-independent conditions. Uncovering the mechanisms of anoikis resistance will provide details about cancer metastasis, and potential strategies against cancer cell dissemination and metastasis. Here, we summarize the principal elements and core molecular mechanisms of anoikis and anoikis resistance. We discuss the latest progress of how anoikis and anoikis resistance are regulated in cancers. Furthermore, we summarize emerging data on selective compounds and nanomedicines, explaining how inhibiting anoikis resistance can serve as a meaningful treatment modality against cancers. Finally, we discuss the key limitations of this therapeutic paradigm and possible strategies to overcome them. In this review, we suggest that pharmacological modulation of anoikis and anoikis resistance by bioactive compounds could surmount anoikis resistance, highlighting a promising therapeutic regimen that could be used to overcome anoikis resistance in cancers.

Identification of chemoresistance associated key genes-miRNAs-TFs in docetaxel resistant breast cancer by bioinformatics analysis

The present study aimed to identify the differentially expressed genes (DEGs) and enriched pathways in docetaxel (DTX) resistant breast cancer cell lines by bioinformatics analysis. The microarray dataset GSE28784 was obtained from gene expression omnibus (GEO) database. The differentially expressed genes (DEGs), gene ontology (GO), and Kyoto Encyclopedia of gene and genome (KEGG) pathway analyses were performed with the help of GEO2R and DAVID tools. Furthermore, the protein-protein interaction (PPI) and hub-gene network of DEGs were constructed using STRING and Cytohubba tools. The prognostic values of hub genes were calculated with the help of the Kaplan-Meier plotter database. From the GEO2R analysis, 222 DEGs were identified of which 120 are upregulated and 102 are downregulated genes. In the PPIs network, five up-regulated genes including CCL2, SPARC, CYR61, F3, and MFGE8 were identified as hub genes. It was observed that low expression of six hub genes CXCL8, CYR61, F3, ICAM1, PLAT, and THBD were significantly correlated with poor overall survival of BC patients in survival analysis. miRNA analysis identified that hsa-mir-16-5p, hsa-mir-335-5p, hsa-mir-124-3p, hsa-mir-20a-5p, and hsa-mir-155-5p are the top 5 interactive miRNAs that are commonly interacting with more hub genes with degree score of greater than five. Additionally, drug-gene interaction analysis was performed to identify drugs which are could potentially elevate/lower the expression levels of hub genes. In summary, the gene-miRNAs-TFs network and subsequent correlation of candidate drugs with hub genes may improve individualized diagnosis and help select appropriate combination therapy for DTX-resistant BC in the future.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13205-024-03971-2.

BDE-209 exposure in murine melanoma (B16-F1) cells modulates tumor malignancy and progression in vivo

Melanoma is a type of skin cancer considered aggressive due to its high metastatic ability and rapid progression to other tissues and organs. BDE-209 (2,2',3,3',4,4',5,5',6,6'-decabromodiphenyl ether) is an additive used as a flame retardant and classified as a persistent organic pollutant that has a high bioaccumulation capacity due to its lipophilic nature. This substance has already been detected in rivers, air, soil, plants and even in different human biological samples, such as plasma, umbilical cord blood and breast milk, revealing a great concern to human populations. Thus, in the current study we investigated whether prior exposure of murine melanoma B16-F1 cells to BDE-209 modulates in vivo progression and malignancy of melanoma. B16-F1 cells were cultured and exposed in vitro to BDE-209 (0.01, 0.1 e 1 nM) for 15 days and then inoculated, via caudal vein, in C57BL/6 mice for experimental metastasis analysis after 20 days. Inoculation of BDE-209-exposed cells resulted in 82% increase of metastasis colonized area in the lungs of mice, downregulation of tumor suppressors genes, such as Timp3 and Reck, decrease of lipid peroxidation and increase of systemic and local inflammatory response. These findings are related to melanoma progression. Additionally, the histopathological analysis revealed greater number of focal points of metastases in the lungs and invasiveness of metastases to the mice brain (89%). The results showed that exposure to BDE-209 may alter the phenotype of B16-F1 cells, worsening their metastatic profile. Current data showed that BDE-209 may interfere with the prognosis of melanoma by modulating cells with less invasiveness capacity to a more aggressive profile.

Hypertension Promotes the Proliferation and Migration of ccRCC Cells by Downregulation of TIMP3 in Tumor Endothelial Cells through the miR-21-5p/TGFBR2/P38/EGR1 Axis

Recent studies have demonstrated that hypertension correlates with tumorigenesis and prognosis of clear-cell renal cell carcinoma (ccRCC); however, the underlying molecular mechanisms remain unclear. By analyzing bulk and single-cell RNA sequencing data and experimental examining of surgical excised ccRCC samples, we found that tissue inhibitors of metalloproteinases 3 (TIMP3), a pivotal paracrine factor in suppressing tumor progression, was significantly reduced in the tumor endothelial cells of patients with hypertensive ccRCC. Besides, in tumor xenograft of NCG mouse model, compared with saline normotensive group the expression of TIMP3 was significantly decreased in the angiotensin II-induced hypertension group. Treating human umbilical vein endothelial cells (HUVEC) with the plasma of patients with hypertensive ccRCC and miR-21-5p, elevated in the plasma of patients with hypertensive ccRCC, reduced the expression of TIMP3 compared with normotensive and control littermates. We also found that the inhibition of TIMP3 expression by miR-21-5p was not through directly targeting at 3'UTR of TIMP3 but through suppressing the expression of TGFβ receptor 2 (TGFBR2). In addition, the knockout of TGFBR2 reduced TIMP3 expression in HUVECs through P38/EGR1 (early growth response protein 1) signaling axis. Moreover, via coculture of ccRCC cell lines with HUVECs and mouse tumor xenograft model, we discovered that the TIMP3 could suppress the proliferation and migration of ccRCC.

IMPLICATIONS

Overall, our findings shed new light on the role of hypertension in promoting the progression of ccRCC and provide a potential therapeutic target for patients with ccRCC with hypertension.

Tissue Inhibitor of Metalloproteinase-3 Ameliorates Diabetes-Induced Retinal Inflammation

Purpose: Endogenous tissue inhibitor of matrix metalloproteinase-3 (TIMP-3) has powerful regulatory effects on inflammation and angiogenesis. In this study, we investigated the role of TIMP-3 in regulating inflammation in the diabetic retina.

Methods: Vitreous samples from patients with proliferative diabetic retinopathy (PDR) and non-diabetic patients were subjected to Western blot analysis. Streptozotocin-treated rats were used as a preclinical diabetic retinopathy (DR) model. Blood-retinal barrier (BRB) breakdown was assessed with fluorescein isothiocyanate (FITC)-conjugated dextran. Rat retinas, human retinal microvascular endothelial cells (HRMECs) and human retinal Müller glial cells were studied by Western blot analysis and ELISA. Adherence of human monocytes to HRMECs was assessed and in vitro angiogenesis assays were performed.

Results: Tissue inhibitor of matrix metalloproteinase-3 in vitreous samples was largely glycosylated. Intravitreal injection of TIMP-3 attenuated diabetes-induced BRB breakdown. This effect was associated with downregulation of diabetes-induced upregulation of the p65 subunit of NF-κB, intercellular adhesion molecule-1 (ICAM-1), and vascular endothelial growth factor (VEGF), whereas phospho-ERK1/2 levels were not altered. In Müller cell cultures, TIMP-3 significantly attenuated VEGF upregulation induced by high-glucose (HG), the hypoxia mimetic agent cobalt chloride (CoCl₂) and TNF-α and attenuated MCP-1 upregulation induced by CoCl₂ and TNF-α, but not by HG. TIMP-3 attenuated HG-induced upregulation of phospho-ERK1/2, caspase-3 and the mature form of ADAM17, but not the levels of the p65 subunit of NF-κB and the proform of ADAM17 in Müller cells. TIMP-3 significantly downregulated TNF-α-induced upregulation of ICAM-1 and VCAM-1 in HRMECs. Accordingly, TIMP-3 significantly decreased spontaneous and TNF-α- and VEGF-induced adherence of monocytes to HRMECs. Finally, TIMP-3 significantly attenuated VEGF-induced migration, chemotaxis and proliferation of HRMECs.

Conclusion:In vitro and in vivo data point to anti-inflammatory and anti-angiogenic effects of TIMP-3 and support further studies for its applications in the treatment of DR.

MicroRNA-21 Contributes to Cutaneous Squamous Cell Carcinoma Progression via Mediating TIMP3/PI3K/AKT Signaling Axis

BACKGROUND

Though the therapeutic potentials of microRNAs (miRNAs) are extensively explored in cutaneous squamous cell carcinoma (CSCC), the concrete function of miR-21 in this disorder has not been thoroughly comprehended. Therein, this work is launched to clarify the miR-21-pivoted mechanism in CSCC from the perspective of tissue inhibitor of metalloproteinases-3 (TIMP3) and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway.

METHODS

Microarray-based analysis was utilized to screen out miR-21 with the most up-regulated expression in CSCC tissues. The relation between miR-21 and TIMP3 expression in tissues, and the overall survival of CSCC patients was evaluated. Loss-of-function assays were performed in cells to explore the independent and combined functions of miR-21 and TIMP3 in CSCC cell progression. Mice were injected with miR-21 inhibitor or TIMP3 si for identifying their roles in tumor formation and liver metastasis. The mechanism among miR-21, TIMP3 and PI3K/AKT pathway was interpreted.

RESULTS

MiR-21 was up-regulated while TIMP3 was down-regulated in CSCC tissues, which were connected with unsatisfactory survival of patients. Down-regulating miR-21 inhibited CSCC cell progression and retarded CSCC tumor formation and metastasis in mice. Silencing of TIMP3 reversed the effects of miR-21 down-regulation on CSCC progression. Besides, down-regulating miR-21 inhibited PI3K/AKT pathway activation in CSCC cells via mediating TIMP3.

CONCLUSION

It is elucidated that miR-21 depletion impedes CSCC cell invasion and metastasis via enhancing TIMP3 and suppressing PI3K/AKT pathway activation.

Association of VEGFA, TIMP-3, and IL-6 gene polymorphisms with predisposition to optic neuritis and optic neuritis with multiple sclerosis

BACKGROUND

The etiology of the inflammatory ON is multifactorial. Much attention is paid to the inflammatory and immune processes that are likely to contribute to the demyelination and MS development. IL-6, VEGFA, and TIMP-3 genes are thought to be involved in the inflammatory processes and manifestation of CNS demyelination, so we aimed to determine the relationship between VEGFA rs1413711, TIMP-3 rs9621532, IL-6 rs1800796 gene polymorphisms and ON, and ON with MS.

MATERIALS AND METHODS

Patients with ON, ON with MS, and a random sample of healthy population were enrolled. The genotyping of VEGFA rs1413711, TIMP-3 rs9621532, and IL-6 rs1800796 polymorphisms was carried out using the real-time polymerase chain reaction method.

RESULTS

T/C and C/C genotypes of VEGFA rs1413711 were associated with about threefold increased odds of developing ON in the dominant and codominant models. Each allele C at VEGFA rs1413711 was associated with 1.7-fold increased odds of ON development. IL-6 rs1800796 allele C was more frequent in the ON with MS group compared to the control: 17.6% vs. 7.5%, respectively (p = .040). No statistically significant associations were found between TIMP-3 rs9621532 and the ON development.

CONCLUSION: VEGFA

rs1413711 is associated with the ON development.

Associations of TIMP-3 Genetic Polymorphisms with EGFR Statuses and Cancer Clinicopathologic Development in Lung Adenocarcinoma Patients

Lung adenocarcinoma (LADC) is a major subtype of lung cancer, particularly among populations of East Asia. The epidermal growth factor receptor (EGFR) is the most frequently mutated oncogene promoting LADC progression and can serve as a therapeutic target in LADC. The tissue inhibitor of metalloproteinases (TIMP)-3 is a major regulator of extracellular matrix turnover via targeting of matrix metalloproteinases (MMPs), and thus, plays a critical role in tumor development and progression. The purpose of this study was to investigate potential associations among TIMP-3 genetic polymorphisms, EGFR statuses, and cancer clinicopathologic development in patients with LADC. In this study, 277 LADC patients with different EGFR statuses were recruited to dissect the allelic discrimination of TIMP-3 -1296 T>C (rs9619311), TIMP3 249T>C (rs9862), and TIMP3 261C>T (rs11547635) polymorphisms using a TaqMan allelic discrimination assay. Our data showed that compared to those LADC patients with wild-type CC homozygotes of TIMP-3 rs9862, patients harboring TT homozygotes of rs9862 were at a higher risk of developing mutant EGFR (adjusted odds ratio (AOR) = 2.530; 95% confidence interval (CI): 1.230–5.205; p = 0.012), particularly the EGFR L858R point mutation (AOR = 2.975; 95% CI: 1.182–7.488; p = 0.021). Moreover, we observed that TIMP-3 TT homozygotes of rs9862 were correlated with the incidence of EGFR mutations in patients with a smoking habit (p = 0.045). Within male patients harboring a mutant EGFR, TIMP-3 rs9862 T (CT+TT) allele carriers were at higher risk of developing an advanced stage (p = 0.025) and lymph node metastasis (p = 0.043). Further analyses of clinical datasets revealed correlations of TIMP-3 expression with a favorable prognosis in patients with LADC. In conclusion, the data suggest that TIMP-3 rs9862 polymorphisms may contribute to identify subgroups of lung cancer patients at high risk for tumor progression, among carriers of LADC-bearing mutant EGFR.

CircFNDC3B sequestrates miR-937-5p to derepress TIMP3 and inhibit colorectal cancer progression

Circular RNA (circRNA) are single‐stranded RNA with covalently closed 3′ and 5′ ends, with many recognized to be involved in human diseases as gene regulators, typically by interacting with other RNA. CircFNDC3B is a circRNA formed by back‐splicing of exons 5 and 6 of the FNDC3B gene. CircFNDC3B was recently implicated in renal carcinoma, gastric and bladder cancer. However, the expression levels of circFNDC3B and its role in colorectal cancer (CRC) remain unclear. Expression of circFNDC3B and TIMP3 levels in CRC tissues and cell lines were found to be low, whereas microRNA (miR)‐937‐5p expression was high in CRC. MicroRNA‐937‐5p downregulated TIMP3, thereby promoting tumor cell proliferation, invasion, migration and angiogenesis. Moreover, CircFNDC3B was shown to bind to miR‐937‐5p. CircFNDC3B and circFNDC3B‐enriched exosomes inhibited tumorigenic, metastatic and angiogenic properties of CRC, and miR‐937‐5p overexpression or TIMP3 knockdown could reverse these effects. In vivo CRC tumor growth, angiogenesis and liver metastasis were suppressed by circFNDC3B overexpression, circFNDC3B‐enriched exosomes or miR‐937‐5p knockdown. In conclusion, our work reports a tumor‐suppressing role for the circFNDC3B–miR‐97‐5p–TIMP3 pathway and suggests that circFNDC3B‐enriched exosomes can inhibit angiogenesis and CRC progression.

MicroRNA-221 promotes proliferation and migration of pulmonary arterial smooth muscle cells (PASMCs) by targeting tissue inhibitor of metalloproteinases-3 (TIMP3)

BACKGROUND

Aberrant vascular smooth muscle cell (VSMC) proliferation and migration play an important role in the development of cardiovascular diseases including pulmonary arterial hypertension (PAH). MicroRNAs (miRNAs, miRs) have been considered to be implicated in the progression of PAH pathogenesis. In this study, we aim to clarify the role of miR-221 on proliferation and migration of pulmonary arterial smooth muscle cells (PASMCs) and identify the target genes involved in this biological process.

METHODS

PASMCs were isolated from the pulmonary arteries of male Sprague-Dawley (SD) rats. Cell proliferation of PASMCs was detected by 5-ethynyl-2'-deoxyuridine (EdU) assay. Cell migration was determined by a scratch wound assay. Quantitative real-time PCR was used to determine the expression of miR-221 while western blot analysis was used to determine the expression of TIMP3. Luciferase assay was used to confirm that TIMP3 was a direct target gene of miR-221. Monocrotaline (MCT) induced-PAH rat model was established and miR-221 and TIMP3 levels were checked in lung tissue and PASMCs from PAH rats.

RESULTS

miR-221 was able to promote the proliferation and migration PASMCs. TIMP3 were negatively regulated by miR-221 at the protein level in PASMCs. In addition, TIMP3 was identified to be a direct target gene of miR-221 in PASMCs based on luciferase assays. TIMP3 knockdown abolished the inhibitory effect of miR-221 inhibitor on PASMCs proliferation and migration, suggesting TIMP3 mediated the effects of miR-221 in PASMCs. Finally, we found that miR-221 was increased while TIMP3 was down-regulated in PASMCs in MCT-treated rats.

CONCLUSIONS

In conclusion, miR-221 promotes PASMCs proliferation and migration by targeting TIMP3. MiR-221 and TIMP3 could be potential therapeutic targets for the treatment of PAH.

DNA Methylation Changes in Human Papillomavirus-Driven Head and Neck Cancers

Disruption of DNA methylation patterns is one of the hallmarks of cancer. Similar to other cancer types, human papillomavirus (HPV)-driven head and neck cancer (HNC) also reveals alterations in its methylation profile. The intrinsic ability of HPV oncoproteins E6 and E7 to interfere with DNA methyltransferase activity contributes to these methylation changes. There are many genes that have been reported to be differentially methylated in HPV-driven HNC. Some of these genes are involved in major cellular pathways, indicating that DNA methylation, at least in certain instances, may contribute to the development and progression of HPV-driven HNC. Furthermore, the HPV genome itself becomes a target of the cellular DNA methylation machinery. Some of these methylation changes appearing in the viral long control region (LCR) may contribute to uncontrolled oncoprotein expression, leading to carcinogenesis. Consistent with these observations, demethylation therapy appears to have significant effects on HPV-driven HNC. This review article comprehensively summarizes DNA methylation changes and their diagnostic and therapeutic indications in HPV-driven HNC.

Tissue inhibitor of matrix metalloproteinase-3 has both anti-metastatic and anti-tumourigenic properties

TIMP-3 is one of four tissue inhibitors of matrix metalloproteinases, the endogenous inhibitors of the matrix metalloproteinase enzymes. These enzymes have an important role in metastasis, in the invasion of cancer cells through the basement membrane and extracellular matrix. TIMP-1, -2 and -4 both promote and inhibit tumour development, in a context-dependent manner, however TIMP-3 is consistently anti-tumourigenic. TIMP-3 is also the only insoluble member of the family, being either bound to the extracellular matrix or the low density lipoprotein-related protein-1, through which it can be endocytosed. Levels of TIMP-3 have also been shown to be regulated by micro RNAs and promoter hypermethylation, resulting in frequent silencing in many tumour types, to the extent that its expression has been suggested as a prognostic marker in some tumours, being associated with lower levels of metastasis, or better response to treatment. TIMP-3 has been shown to have anti-metastatic effects, both through inhibition of matrix metalloproteinases and ADAM family members and downregulation of angiogenesis. This occurs via interactions with receptors including VEGF, via modulation of signaling pathways and due to protease inhibition. TIMP-3 has also been shown to reduce tumour growth rate, most often by inducing apoptosis by stabilisation of death receptors. A number of successful mechanisms of delivery of TIMP-3 to tumour or inflammatory sites have been investigated in vitro or in animal studies. It may therefore be worthwhile further exploring the use of TIMP-3 as a potential anti-metastatic or anti-tumorigenic therapy for many tumour types.

Exosome-dependent immune surveillance at the metastatic niche requires BAG6 and CBP/p300-dependent acetylation of p53

Extracellular vesicles released by tumor cells contribute to the reprogramming of the tumor microenvironment and interfere with hallmarks of cancer including metastasis. Notably, melanoma cell-derived EVs are able to establish a pre-metastatic niche in distant organs, or on the contrary, exert anti-tumor activity. However, molecular insights into how vesicles are selectively packaged with cargo defining their specific functions remain elusive.

Methods: Here, we investigated the role of the chaperone Bcl2-associated anthogene 6 (BAG6, synonym Bat3) for the formation of pro- and anti-tumor EVs. EVs collected from wildtype cells and BAG6-deficient cells were characterized by mass spectrometry and RNAseq. Their tumorigenic potential was analyzed using the B-16V transplantation mouse melanoma model.

Results: We demonstrate that EVs from B-16V cells inhibit lung metastasis associated with the mobilization of Ly6C^low patrolling monocytes. The formation of these anti-tumor-EVs was dependent on acetylation of p53 by the BAG6/CBP/p300-acetylase complex, followed by recruitment of components of the endosomal sorting complexes required for transport (ESCRT) via a P(S/T)AP double motif of BAG6. Genetic ablation of BAG6 and disruption of this pathway led to the release of a distinct EV subtype, which failed to suppress metastasis but recruited tumor-promoting neutrophils to the pre-metastatic niche.

Conclusion: We conclude that the BAG6/CBP/p300-p53 axis is a key pathway directing EV cargo loading and thus a potential novel microenvironmental therapeutic target.

The Methylation Status of the Epigenome: Its Emerging Role in the Regulation of Tumor Angiogenesis and Tumor Growth, and Potential for Drug Targeting

Approximately 50 years ago, Judah Folkman raised the concept of inhibiting tumor angiogenesis for treating solid tumors. The development of anti-angiogenic drugs would decrease or even arrest tumor growth by restricting the delivery of oxygen and nutrient supplies, while at the same time display minimal toxic side effects to healthy tissues. Bevacizumab (Avastin)—a humanized monoclonal anti VEGF-A antibody—is now used as anti-angiogenic drug in several forms of cancers, yet with variable results. Recent years brought significant progresses in our understanding of the role of chromatin remodeling and epigenetic mechanisms in the regulation of angiogenesis and tumorigenesis. Many inhibitors of DNA methylation as well as of histone methylation, have been successfully tested in preclinical studies and some are currently undergoing evaluation in phase I, II or III clinical trials, either as cytostatic molecules—reducing the proliferation of cancerous cells—or as tumor angiogenesis inhibitors. In this review, we will focus on the methylation status of the vascular epigenome, based on the genomic DNA methylation patterns with DNA methylation being mainly transcriptionally repressive, and lysine/arginine histone post-translational modifications which either promote or repress the chromatin transcriptional state. Finally, we discuss the potential use of “epidrugs” in efficient control of tumor growth and tumor angiogenesis.

miR-29c plays a suppressive role in breast cancer by targeting the TIMP3/STAT1/FOXO1 pathway

Background

miR-29c has been associated with the progression of many cancers. However, the function and mechanism of miR-29c have not been well investigated in breast cancers.

Methods

Real-time quantitative PCR was used to assess expression of miR-29c and DNMT3B mRNA. Western blot and immunochemistry were used to examine the expression of DNA methyltransferase 3B (DNMT3B) protein in breast cancer cells and tissues. The functional roles of miR-29c in breast cancer cells such as proliferation, migration, invasion, colony formation, and 3D growth were evaluated using MTT, transwell chambers, soft agar, and 3D Matrigel culture, respectively. In addition, the luciferase reporter assay was used to check if miR-29c binds the 3'UTR of DNMT3B. The effects of miR-29c on the DNMT3B/TIMP3/STAT1/FOXO1 pathway were also examined using Western blot and methyl-specific qPCR. The specific inhibitor of STAT1, fludarabine, was used to further check the mechanism of miR-29c function in breast cancer cells. Studies on cell functions were carried out in DNMT3B siRNA cell lines.

Results

The expression of miR-29c was decreased with the progression of breast cancers and was closely associated with an overall survival rate of patients. Overexpression of miR-29c inhibited the proliferation, migration, invasion, colony formation, and growth in 3D Matrigel while knockdown of miR-29c promoted these processes in breast cancer cells. In addition, miR-29c was found to bind 3'UTR of DNMT3B and inhibits the expression of DNMT3B, which was elevated in breast cancers. Moreover, the protein level of TIMP3 was reduced whereas methylation of TIMP3 was increased in miR-29c knockdown cells compared to control. On the contrary, the protein level of TIMP3 was increased whereas methylation of TIMP3 was reduced in miR-29c-overexpressing cells compared to control. Knockdown of DNMT3B reduced the proliferation, migration, and invasion of breast cancer cell lines. Finally, our results showed that miR-29c exerted its function in breast cancers by regulating the TIMP3/STAT1/FOXO1 pathway.

Conclusion

The results suggest that miR-29c plays a significant role in suppressing the progression of breast cancers and that miR-29c may be used as a biomarker of breast cancers.

TIMP3 Overexpression Improves the Sensitivity of Osteosarcoma to Cisplatin by Reducing IL-6 Production

Osteosarcoma is the most common bone cancer in children and adolescents. Tissue inhibitors of metalloproteinases (TIMPs)-3 inhibit matrix metalloproteinases to limit extracellular matrix degradation. Cisplatin is a widely used chemotherapeutic drug used to cure osteosarcoma. Interleukin (IL)-6 and TIMP3 play important roles in the drug resistance of osteosarcoma; however, their relationship in this process remains unclear. This study aimed to explore the role of TIMP3 in the cisplatin sensitivity of osteosarcoma and its underlying molecular mechanisms in vitro and in vivo. We compared TIMP3 expression levels between patients with cisplatin-sensitive and -insensitive osteosarcoma. TIMP3 was overexpressed or knocked down in the Saos2-lung cell line, which is a Saos2 subtype isolated from pulmonary metastases that has higher cisplatin chemoresistance than Saos2 cells. IL-6 expression, cell proliferation, sensitivity to cisplatin, migration, and invasion after TIMP3 overexpression or knockdown were determined. The same experiments were performed using MG63 and U2OS cells. Subsequently, luciferase-labeled Saos2-lung cells overexpressing TIMP3 were injected into the tibiae of nude mice treated with cisplatin. The results showed that IL-6 inhibited TIMP3 expression in Saos2 and Saos2-lung cells via signal transducer and activator of transcription 3 (STAT3) activation. STAT3 knockdown reversed the effect of IL-6. The expression of TIMP3 was higher in patients with cisplatin-sensitive osteosarcoma than in those with insensitive osteosarcoma. IL-6 expression was downregulated upon TIMP3 overexpression, and upregulated by TIMP3 knockdown. TIMP3 overexpression suppressed cell proliferation and enhanced cisplatin sensitivity by activating apoptosis-related signal pathways and inhibiting IL-6 expression in vitro and in vivo. In conclusion, cisplatin sensitivity correlated positively with TIMP3 expression, which is regulated by the IL-6/TIMP3/caspase pathway. The TIMP3 pathway could represent a target for new therapies to treat osteosarcoma.

The Association of BRAF V600E Mutation With Tissue Inhibitor of Metalloproteinase-3 Expression and Clinicopathological Features in Papillary Thyroid Cancer

BACKGROUND

Papillary thyroid cancer (PTC) is the most common endocrine malignancy. The aim of this study was to investigate the association of tissue inhibitor metalloproteinase-3 (TIMP3) mRNA and protein levels in thyroid tissues, based on BRAF V600E status with the clinicopathologic characteristics of PTC.

METHODS

A total of 60 fresh frozen tissue samples of PTC patients (15 male and 45 female) were collected during thyroidectomy. All clinicopathological information was obtained and samples were reviewed as well as confirmed by a pathologist; exon 15 of the BRAF gene was genotyped by sequencing, TIMP3 mRNA level was assessed using SYBR-Green Real-Time PCR, and TIMP3 protein level was measured using ELISA.

RESULTS

Of 60 cases, BRAF mutation was found in 24 (40%). Larger tumor size and higher lymph node metastasis frequency were observed, significant in BRAF (+), compared to the BRAF (-) PTC group (P = 0.039 and P = 0.03, respectively). No significant difference was seen in the tumoral tissues of the TIMP3 mRNA level in BRAF (+), compared to BRAF (-) PTC samples. However, the mean TIMP3 protein level was significantly lower in tumoral tissues, compared to matched non-tumoral tissues in BRAF (+) PTC (P=0.003); TIMP3 protein level was significantly lower in tumoral tissues compared to matched non-tumoral tissues in BRAF (+), in subjects who had no lymph node metastasis and also in subjects with lymph node metastasis in both BRAF positive and negative PTC cases.

CONCLUSION

Our results showed that BRAF mutation was associated with a larger tumor size, higher frequency of lymph node metastasis, and lower TIMP3 protein levels. Lower TIMP3 protein level was associated with the lymph node metastasis in PTC patients.

IL-32 gamma reduces lung tumor development through upregulation of TIMP-3 overexpression and hypomethylation

The low expression of tissue inhibitor of metalloproteinase 3 (TIMP-3) is important in inflammatory responses. Therefore, inhibition of TIMP-3 may promote tumor development. Our study showed that expression of TIMP-3 was elevated in lL-32γ mice lung tissues. In this study, we investigated whether IL-32γ mice inhibited lung tumor development through overexpression of TIMP-3 and its methylation. To explore the possible underlying mechanism, lung cancer cells were transfected with IL-32γ cDNA plasmid. A marked increase in TIMP-3 expression was caused by promoter methylation. Mechanistic studies indicated that TIMP-3 overexpression reduced NF-κB activity, which led to cell growth inhibition in IL-32γ transfected lung cancer cells. We also showed that IL-32γ inhibits expression of DNA (cytosine-5-)-methyltransferase 1 (DNMT1). Moreover, IL-32γ inhibits the binding of DNMT1 to TIMP-3 promoter, but this effect was reversed by the treatment of DNA methyltransferase inhibitor (5-Aza-CdR) and NF-κB inhibitor (PS1145), suggesting that a marked increase in TIMP-3 expression was caused by inhibition of promoter hypermethylation via decreased DNMT1 expression through the NF-κB pathway. In an in vivo carcinogen induced lung tumor model, tumor growth was inhibited in IL-32γ overexpressed mice with elevated TIMP-3 expression and hypomethylation accompanied with reduced NF-κB activity. Moreover, in the lung cancer patient tissue, the expression of IL-32 and TIMP-3 was dramatically decreased at a grade-dependent manner compared to normal lung tissue. In summary, IL-32γ may increase TIMP-3 expression via hypomethylation through inactivation of NF-κB activity, and thereby reduce lung tumor growth.

Aberrant DNA methylation in melanoma: biomarker and therapeutic opportunities

Aberrant DNA methylation is an epigenetic hallmark of melanoma, known to play important roles in melanoma formation and progression. Recent advances in genome-wide methylation methods have provided the means to identify differentially methylated genes, methylation signatures, and potential biomarkers. However, despite considerable effort and advances in cataloging methylation changes in melanoma, many questions remain unanswered.

The aim of this review is to summarize recent developments, emerging trends, and important unresolved questions in the field of aberrant DNA methylation in melanoma. In addition to reviewing recent developments, we carefully synthesize the findings in an effort to provide a framework for understanding the current state and direction of the field. To facilitate clarity, we divided the review into DNA methylation changes in melanoma, biomarker opportunities, and therapeutic developments. We hope this review contributes to accelerating the utilization of the diagnostic, prognostic, and therapeutic potential of DNA methylation for the benefit of melanoma patients.

miR-181b-5p Modulates Cell Migratory Proteins, Tissue Inhibitor of Metalloproteinase 3, and Annexin A2 During In Vitro Decidualization in a Human Endometrial Stromal Cell Line

Decidualization is essential for successful embryo implantation and is regulated by concerted actions of growth factors and hormones. More recently, microRNAs, small RNA molecules that regulate posttranscriptional gene expression, have been implicated to play a role in the decidualization process. Of these microRNAs, miR-181b-5p has been associated with decidualization but its precise role and targets are not well established. To address this gap in our knowledge, we assessed the expression of miR-181b-5p, and its target tissue inhibitor of metalloproteinase 3 (TIMP-3), during in vitro decidualization using the well-characterized human endometrial stromal cell line, t-HESC. miR-181b-5p expression was highest prior to decidualization and significantly decreased in response to decidualization stimulus. In contrast, TIMP-3 expression was absent prior to in vitro decidualization and increased during decidualization. Regulation of TIMP-3 expression by miR-181b-5p was confirmed in vitro by quantitative reverse transcription polymerase chain reaction (qRT-PCR), Western blot analysis, and 3' untranslated region reporter constructs. To identify unforeseen targets of miR-181b-5p during in vitro decidualization, t-HESC cells were transfected with pre- miR-181b-5p, and protein profiles were determined by 2-dimensional differential in-gel electrophoresis followed by matrix-assisted laser desorption-ionization time-of-flight/time-of-flight (MALDI TOF/TOF) tandem mass spectrometry. Of these proteins, several downregulated proteins associated with cell migration were identified including annexin A2, which we subsequently confirmed by qRT-PCR and Western blot analysis to be regulated by miR-181b-5p. In conclusion, miR-181b-5p is downregulated during the process of in vitro decidualization and may regulate the expression of proteins associated with cell migration including TIMP-3 and annexin A2.