Role of serum matrix metalloproteinase-2 and -9 to predict breast cancer progression

Target-induced hot spot construction for sensitive and selective surface-enhanced Raman scattering detection of matrix metalloproteinase MMP-9

Studies have found that matrix metalloproteinase-9 (MMP-9) plays a significant role in cancer cell invasion, metastasis, and tumor growth. But it is a challenge to go for highly sensitive and selective detection and targeting of MMP-9 due to the similar structure and function of the MMP proteins family. Herein, a novel surface-enhanced Raman scattering (SERS) sensing strategy was developed based on the aptamer-induced SERS "hot spot" formation for the extremely sensitive and selective determination of MMP-9. To develop the nanosensor, one group of gold nanospheres was modified with MMP-9 aptamer and its complementary strand DNA1, while DNA2 (complementary to DNA1) and the probe molecule 5,5'-dithiobis-(2-nitrobenzoic acid) (DTNB) were grafted on the surface of the other group of gold nanospheres. In the absence of MMP-9, DTNB located on the 13-nm gold nanospheres has only generated a very weak SERS signal. However, when MMP-9 is present, the aptamer preferentially binds to the MMP-9 to construct MMP-9-aptamer complex. The bare DNA1 can recognize and bind to DNA2, which causes them to move in close proximity and create a SERS hot spot effect. Due to this action, the SERS signal of DTNB located at the nanoparticle gap is greatly enhanced, achieving highly sensitive detection of MMP-9. Since the hot spot effect is caused by the aptamer that specifically recognizes MMP-9, the approach exhibits excellent selectivity for MMP-9 detection. Based on the benefits of both high sensitivity and excellent selectivity, this method was used to distinguish the difference in MMP-9 levels between normal and cancer cells as well as the expression of MMP-9 from cancer cells with different degrees of metastasis. In addition, this strategy can accurately reflect the dynamic changes in intracellular MMP-9 levels, stimulated by the MMP-9 activator and inhibitor. This strategy is expected to be transformed into a new technique for diagnosis of specific cancers related to MMP-9 and assessing the extent of cancer occurrence, development and metastasis.

A Dual-Enzyme Amplification Loop for the Sensitive Biosensing of Endopeptidases

A rapid and sensitive approach for the detection of endopeptidases via a new analyte-triggered mutual emancipation of linker-immobilized enzymes (AMELIE) mechanism has been developed and demonstrated using a matrix metallopeptidase, a collagenase, as the model endopeptidase analyte. AMELIE involves an autocatalytic loop created by a pair of selected enzymes immobilized on solid substrates via linkers with specific sites that can be proteolyzed by one another. These bound enzymes are spatially separated so that they cannot act upon their corresponding substrates until the introduction of the target endopeptidase analyte that can also cleave one of the linkers. This triggers the self-sustained loop of enzymatic activities to emancipate all the immobilized enzymes. In this proof of concept, signal transduction was achieved by a colorimetric horseradish peroxidase-tetramethylbenzidine (HRP-TMB-H₂O₂) reaction with HRP that are also being immobilized by one of the linkers. The pair of immobilized enzymes were collagenase and alginate lyase, and they were immobilized by an alginate linker and a short peptide chain containing the amino acid sequence of Leu-Gly-Pro-Ala for collagenase. A detection limit of 2.5 pg collagenase mL^-1 with a wide linear range up to 4 orders of magnitude was achieved. The AMELIE biosensor can detect extracellular collagenase in the supernatant of various bacteria cultures, with a sensitivity as low as 10³ cfu mL^-1 of E. coli. AMELIE can readily be adapted to provide the sensitive detection of other endopeptidases.

Transformable Neuropeptide Prodrug with Tumor Microenvironment Responsiveness for Tumor Growth and Metastasis Inhibition of Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) has the worst prognosis among all breast cancer subtypes due to lack of specific target sites and effective treatments. Herein, a transformable prodrug (DOX-P18) based on neuropeptide Y analogue with tumor microenvironment responsiveness is developed for TNBC treatment. The prodrug DOX-P18 can achieve reversible morphological transformation between monomers and nanoparticles through the manipulation of protonation degree in different environments. It can self-assemble into nanoparticles to enhance the circulation stability and drug delivery efficiency in the physiological environment while transforming from nanoparticles to monomers and being endocytosed into the breast cancer cells in the acidic tumor microenvironment. Further, the DOX-P18 can precisely be enriched in the mitochondria, and efficiently activated by matrix metalloproteinases. Then, the cytotoxic fragment (DOX-P3) can subsequently be diffused into the nucleus, generating a sustained cell toxicity effect. In the meanwhile, the hydrolysate residue P15 can assemble into nanofibers to construct nest-like barriers for the metastasis inhibition of cancer cells. After intravenous injection, the transformable prodrug DOX-P18 demonstrated superior tumor growth and metastasis suppression with much better biocompatibility and improved biodistribution compared to free DOX. As a novel tumor microenvironment-responsive transformable prodrug with diversified biological functions, DOX-P18 shows great potential in smart chemotherapeutics discovery for TBNC.

Plasma Levels of Metalloproteinase 3 (MMP-3) and Metalloproteinase 7 (MMP-7) as New Candidates for Tumor Biomarkers in Diagnostic of Breast Cancer Patients

Matrix metalloproteinases (MMPs) are a group of enzymes that mediate both physiological and pathological processes such as carcinogenesis. The role of matrix metalloproteinase-3 (MMP-3) and (MMP-7) in the pathogenesis of breast cancer (BC) has been demonstrated, suggesting that they may be considered as potential markers of this condition. The aim of this study was to assess plasma concentrations and diagnostic utility of MMP-3 and MMP-7 in 100 patients with early-stage breast cancer with Luminal A subtype or Luminal B HER-negative subtype, before and after surgical treatment, and in the following control groups: patients with a benign tumor (fibroadenoma) and healthy subjects. The concentrations of MMP-3 and MMP-7 were referenced to the levels of the widely recognized marker for BC diagnosis CA 15-3. MMP-3 and MMP-7 was measured by ELISA method and CA 15-3 by CMIA. Plasma levels of MMP-7 were significantly higher in Luminal A and Luminal B HER2-negative subtype breast cancer patients as compared to the healthy group. MMP-7 demonstrated comparable but mostly higher to CA 15-3 or MMP-3 values of diagnostic sensitivity, specificity, positive and negative predictive values and AUC (0.6888 for Luminal A subtype; 0.7612 for Luminal B HER2-negative; 0.7250 for BC total group, respectively) in the groups tested. The combined use of the tested parameters resulted in a further increase in diagnostic criteria and AUC. These results suggest the usefulness of combining MMP-7 with CA 15-3 in the diagnostics of breast cancer, especially in Luminal B HER2-negative subtypes patients, as a new candidate for tumor markers.

Target-activated cascade transcription amplification lights up RNA aptamers for label-free detection of metalloproteinase-2 activity

We demonstrate that target-activated cascade transcription amplification lights up RNA aptamers for label-free detection of metalloproteinase-2 (MMP-2) activity with zero background. This assay exhibits good specificity and high sensitivity with a limit of detection (LOD) of 0.6 fM. Moreover, it can analyze enzyme kinetic parameters, screen inhibitors, and accurately quantify MMP-2 in cancer cells and clinical serums.

Circulating proteins as predictive and prognostic biomarkers in breast cancer

Breast cancer (BC) is the most common cancer and among the leading causes of cancer death in women. It is a heterogeneous group of tumours with numerous morphological and molecular subtypes, making predictions of disease evolution and patient outcomes difficult. Therefore, biomarkers are needed to help clinicians choose the best treatment for each patient. For the last years, studies have increasingly focused on biomarkers obtainable by liquid biopsy. Circulating proteins (from serum or plasma) can be used for inexpensive and minimally invasive determination of disease risk, early diagnosis, treatment adjusting, prognostication and disease progression monitoring. We provide here a review of the main published studies on serum proteins in breast cancer and elaborate on the potential of circulating proteins to be predictive and/or prognostic biomarkers in breast cancer.

Mass-Encoded Suspension Array for Multiplex Detection of Matrix Metalloproteinase Activities

This work designed a mass spectrometric biosensing strategy for the multiplex detection of matrix metalloproteinases (MMPs) with a mass-encoded suspension array. This array was fabricated as multiplex sensing probes by functionalizing magnetic beads with MMP-specific peptide-isobaric tags for relative and absolute quantification (iTRAQ) conjugates, which contained a hexahistidine tag for surface binding, a substrate region for MMP cleavage, and a coding region for the specific MMP. The integration of the multiplex coding ability of iTRAQ with ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and the proteolysis method for peptide digestion endowed the biosensing method with high throughput and ultrahigh sensitivity. This strategy could be conveniently performed by mixing the sample and the suspension array for enzymatic reactions and then digesting the uncleaved peptides with trypsin to release the coding regions for UPLC-MS/MS analysis. With MMP-2 and MMP-7 as analytes, the relative changes of peak area ratios of coding regions showed good linear responses in the ranges of 0.2-100 and 0.5-400 ng mL^-1, with detection limits of 0.064 and 0.17 ng mL^-1, respectively. The analysis of MMP activity in serum samples and its change responding to inhibitors demonstrated the specificity, practicability, and expansibility of the proposed strategy. This work paves a new avenue for the activity assays of multiplex enzymes and promotes the development of mass spectrometric biosensing.

Matrix metalloproteinase-9 (MMP-9) promoter -1562C/T functional polymorphism is associated with an increased risk to develop micropapillary thyroid carcinoma

BACKGROUND

Matrix metalloproteinase-9 (MMP-9) is an important mediator of tumor initiation and progression. The MMP-9 promoter -1562C/T functional polymorphism increases gene expression and was identified as a susceptibility factor for various cancers.

OBJECTIVE

To evaluate the influence of the MMP-9 promoter genotype on the risk of developing papillary thyroid cancer (PTC) and to correlate cancer patient genotype with the clinical and pathological phenotype.

METHODS

We evaluated 236 patients with nodular thyroid disease pre-thyroidectomy (119 benign disease, 117 PTC). Genomic DNA was isolated from whole blood and the MMP-9 -1562C/T genotype was evaluated by PCR-RFLP analysis.

RESULTS

Genotype frequencies were in Hardy-Weinberg equilibrium for all groups. The T allele was significantly more frequent in cancer compared to benign disease (17.5% vs 10.1%), p= 0.019. Patients with the CT or CT+TT genotype had an increased risk of developing PTC, specifically micropapillary thyroid carcinoma (MPTC) (CT genotype: OR = 6.467, p= 0.00006; CT+TT: OR = 6.859, p= 0.00002), but not more advanced stages (CT: p= 0.094; CT+TT: p= 0.157). The -1562C/T genotype did not significantly correlate with tumor histological subtype, invasion or TNM stage.

CONCLUSION

The MMP-9 -1562C/T functional polymorphism may indicate susceptibility to develop thyroid cancer, specifically intrathyroidal clinically non-relevant MPTC. This suggests that although this genotype might be a predisposing factor, other genetic/epigenetic events are needed for cancer progression.

Smartphone-based photoelectrochemical biosensing system with graphitic carbon nitride/gold nanoparticles modified electrodes for matrix metalloproteinase-2 detection

Photoelectrochemical analysis has been widely used in the field of biosensing due to its high sensitivity and strong anti-interference ability. Herein, a portable and versatile smartphone-based photoelectrochemical biosensing platform was developed for the rapid and on-site biomedical analysis. In the system, light excitation and photocurrent measurements were accomplished by a miniaturized and integrated circuit board. Smartphone with a specifically designed application was utilized to wirelessly control the system via Bluetooth. For photoelectrochemical sensor, graphitic carbon nitride (g-C₃N₄) and gold nanoparticles loaded on indium tin oxide electrodes were utilized as photoactive materials and signal amplification elements, respectively. The gold nanoparticles were also used to immobilized matrix metalloproteinase-2 (MMP-2) specific cleavage peptide that modified with bovine serum albumin (BSA) on the terminal. In the presence of MMP-2, the peptide was specifically hydrolyzed and cleaved. Thus, parts of the peptide chain and BSA were detached from the electrode resulting in the decrease of steric hindrance and the increase of photoelectrochemical currents. The photocurrents changed linearly with the logarithm of MMP-2 concentrations ranging from 1 pg/mL to 100 ng/mL in both buffer and artificial serum with correlation coefficient of 0.9943 and 0.9698. The limit of detections were as low as 0.48 pg/mL in buffer and 0.55 pg/mL in artifical serum. It indicated that the biosensor has good linearity and high sensitivity, which also verified the effectiveness of the portable instrument. This system provides a pioneering solution for the development of miniaturized and portable photoelectrochemical analysis instruments used for the field monitoring of different analytes.

Serum Matrix metalloproteinase-9 (MMP-9) can help identify patients with papillary thyroid cancer at high risk of persistent disease: Value and limitations of a potential marker of neoplasia

BACKGROUND

Matrix metalloproteinase-9 (MMP-9) is an important mediator of invasion and metastasis in neoplasia. In thyroid cancer expression levels correlate with aggressiveness but data on peripheral MMP-9 levels are less definitive.

OBJECTIVE

Prospective study evaluating serum MMP-9 in the diagnosis and prognosis of papillary thyroid cancer.

METHODS

Serum samples of MMP-9 were drawn before surgery in 185 consecutively enrolled patients with nodular thyroid disease, stratified on pathology as benign disease (N= 88) and papillary thyroid cancer (N= 97). Serum MMP-9 was measured by an immunometric assay.

RESULTS

MMP-9 levels were not different between benign vs malignant pathology (p= 0.3). In papillary thyroid cancer there was no significant difference in MMP-9 levels between histologies, TNM stage and invasive/non-invasive cancers. High-risk patients with multiple features of aggressiveness had significantly higher MMP-9 levels compared to low-intermediate risk patients (767.5 ± 269.2 ng/ml vs 563.7 ± 228.4 ng/ml, p= 0.019). A cut-off of 806 ng/ml distinguished high from low-intermediate risk patients with a sensitivity of 60% and a specificity of 87.36%, p= 0.018. In patients with available follow-up data (N= 78), MMP-9 was higher in patients who required ⩾ 2 doses of 131I therapy (p= 0.009) and in those with biochemical evidence of persistent disease/who required additional therapy to achieve disease-free status (p= 0.017).

CONCLUSION

Serum MMP-9 is not useful in the diagnosis of PTC, but preliminary data shows that high pre-surgical serum MMP-9 levels may identify patients at higher risk of persistent disease who require intensive treatment. Large volume prospective studies are required to confirm this observation.

Amplified and label-free electrochemical detection of a protease biomarker by integrating proteolysis-triggered transcription

Cell-free synthetic biology provides a promising strategy for developing high-performance biosensors by integrating with advanced testing technologies. However, the combination of synthetic biology with electrochemical testing techniques is still underdeveloped. Here, we proposed an electrochemical biosensor for the label-free and ultrasensitive detection of target protease biomarker by coupling a protease-responsive RNA polymerase (PR) for signal amplification. Taking tumor biomarker matrix metalloprotease-2 (MMP-2) as a model protease, we employed PR to transduce each proteolysis reaction mediated by MMP-2 into multiple programmable RNA outputs that can be captured by the DNA probes immobilized on a gold electrode. Moreover, the captured RNAs are designed to contain a guanine-rich sequence that can form G-quadruplex and bind to hemin in the presence of potassium ions. In this scenario, the activity of MMP-2 is converted and amplified into the electrochemical signals of hemin. Under the optimal conditions, this PR-based electrochemical biosensor enabled the sensitive detection of MMP-2 in a wide linear dynamic range from 10 fM to 1.0 nM, with a limit of detection of 7.1 fM. Moreover, the proposed biosensor was further applied in evaluating MMP-2 activities in different cell cultures and human tissue samples, demonstrating its potential in the analysis of protease biomarkers in complex clinical samples.

A label-free and homogenous electrochemical assay for matrix metalloproteinase 2 activity monitoring in complex samples based on electrodes modified with orderly distributed mesoporous silica films

Herein, a label-free and homogeneous electrochemical strategy for monitoring of matrix metalloproteinase 2 (MMP-2) activity was proposed based on electrodes modified with orderly distributed mesoporous silica films (MSFs). In the absence of target MMP-2, an artificially substrate peptide with positive charge was absorbed on the surface of MSFs by electrostatic interaction, which could prevent electrochemical molecules [Ru(NH₃)₆]Cl₃ from approaching the electrode surface. When the substrate peptide was hydrolyzed by target MMP-2, [Ru(NH₃)₆]Cl₃ could arrive to the electrode surface and lead to the increase of electrochemical signal. This assay showed considerable sensitivity to target MMP-2, which could measure it down to 0.98 ng. mL^-1. Meanwhile, a satisfied response to the inhibitor of MMP-2 was also achieved (IC-50 value = 1.68 μM). Significantly, it displayed satisfactory performances in the complicated biological samples including cell lysates and human serum. Taking advantages of the anti-fouling ability in biological complex samples of MSFs and the high efficiency of homogeneous sensing, this assay realized the electrochemical detection of MMP-2 with accuracy and sensitivity, which exhibited significant potential in clinical biomedicine and biological analysis of cancer-related protease.

Use of a Recombinant Biomarker Protein DDA Library Increases DIA Coverage of Low Abundance Plasma Proteins

Credible detection and quantification of low abundance proteins from human blood plasma is a major challenge in precision medicine biomarker discovery when using mass spectrometry (MS). In this proof-of-concept study, we employed a mixture of selected recombinant proteins in DDA libraries to subsequently identify (not quantify) cancer-associated low abundance plasma proteins using SWATH/DIA. The exemplar DDA recombinant protein spectral library (rPSL) was derived from tryptic digestion of 36 recombinant human proteins that had been previously implicated as possible cancer biomarkers from both our own and other studies. The rPSL was then used to identify proteins from nondepleted colorectal cancer (CRC) EDTA plasmas by SWATH-MS. Most (32/36) of the proteins used in the rPSL were reliably identified from CRC plasma samples, including 8 proteins (i.e., BTC, CXCL10, IL1B, IL6, ITGB6, TGFα, TNF, TP53) not previously detected using high-stringency protein inference MS according to PeptideAtlas. The rPSL SWATH-MS protocol was compared to DDA-MS using MARS-depleted and postdigestion peptide fractionated plasmas (here referred to as a human plasma DDA library). Of the 32 proteins identified using rPSL SWATH, only 12 could be identified using DDA-MS. The 20 additional proteins exclusively identified using the rPSL SWATH approach were almost exclusively lower abundance (i.e., <10 ng/mL) proteins. To mitigate justified FDR concerns, and to replicate a more typical library creation approach, the DDA rPSL library was merged with a human plasma DDA library and SWATH identification repeated using such a merged library. The majority (33/36) of the low abundance plasma proteins added from the rPSL were still able to be identified using such a merged library when high-stringency HPP Guidelines v3.0 protein inference criteria were applied to our data set. The MS data set has been deposited to ProteomeXchange Consortium via the PRIDE partner repository (PXD022361).

Decreased expression of serum semaphorin 3B is associated with poor prognosis of patients with hepatocellular carcinoma

Semaphorin 3B (SEMA-3B), which belongs to the semaphorin family, has an important role in cell apoptosis and inhibition of angiogenesis. A previous study by our group revealed that SEMA-3B was downregulated in tumor tissues of patients with hepatocellular carcinoma (HCC) and exerts anti-motility and anti-invasion effects on tumor cells. However, the serum levels of SEMA-3B and their clinical significance have remained elusive; therefore, the aim of the present study was to monitor its expression in HCC and investigate its clinical significance. ELISA was used to determine the serum levels of SEMA-3B in 132 patients with HCC and 57 healthy individuals. The association between SEMA-3B and clinicopathological parameters was investigated. Serum SEMA-3B was indicated to be significantly decreased in patients with HCC as compared with that in the controls (P<0.05) and it was negatively associated with tumor size (P=0.039), encapsulation (P=0.002) and TNM stage (P=0.034). The prognosis of patients with low expression of SEMA-3B was poor. In conclusion, the results of the present study revealed that serum SEMA-3B is decreased in HCC and is negatively associated with prognosis; therefore, it may be used as a prognostic marker in HCC.

Association between the polymorphisms in MMP-2 and MMP-9 with adiposity and mammographic features

BACKGROUND

Matrix metalloproteinases (MMP)-2 and -9 may play an important role in adipogenesis and carcinogenesis. We investigated whether some polymorphisms located in these genes are associated with body adiposity and mammographic breast density, which are risk factors for breast cancer.

METHODS

Our study population included 731 premenopausal women. Multivariate generalized linear models were used to evaluate the association of polymorphisms rs243865 in MMP-2 and rs3918242, rs17576, rs2250889 and rs2274756 in MMP-9 with anthropometric factors that refer to adiposity and mammographic features (percent density, dense area and non-dense area) measured by computer-assisted method.

RESULTS

The number of copies of rs243865 T allele in MMP-2 was associated with increased means of anthropometric factors (p_trend < 0.05 for all except waist-to-hip ratio). The same allele of rs243865 was associated with decreased mean percent density (p_trend = 0.036) and increased mean non-dense area (p_trend = 0.031) when adjusted for potential confounders, but these associations were attenuated when further adjusted for adiposity.

CONCLUSION

These findings suggest that the relation between rs243865 in MMP-2 and mammographic features could be mediated by adiposity.

Expression of matrix metalloproteinase 2 and 9 in breast cancer and breast fibroadenoma: a randomized, double-blind study

Background

Matrix metalloproteinases (MMPs) 2 and 9 may play an important role in cell proliferation and dissemination of cancer. However, few studies have compared the expression of these proteins between breast cancer and fibroadenoma.

Material and methods

A randomized, double-blind study was carried out in 66 premenopausal women, aged 20-49 years, who had been diagnosed with fibroadenoma or breast cancer. The patients were divided into two groups: Group A, control (fibroadenoma, n=36) and Group B, study (cancer, n=30). Immunohistochemical analysis was performed using tissue samples of fibroadenoma and breast cancer to assess MMP-2 and MMP-9 antigen expression. Cells were considered positive if exhibiting brown cytoplasmic staining. Fisher’s exact test was used to compare the percentage of cases with cells expressing MMP-2 and MMP-9 in control and study groups (p < 0.05).

Results

Light microscopy showed a higher concentration of cells with positive cytoplasmic staining for MMP-2 and MMP-9 expression in breast cancer than in fibroadenoma. The percentage of cases with cells expressing MMP-2 in the control and study groups was 41.67% and 86.11%, respectively (p < 0.0009), whereas the percentage of cases with cells expressing MMP-9 in groups A and B was 66.67% and 93.33%, respectively (p<0.0138). MMP-2 and MMP-9 positive expression was significantly higher in moderately differentiated tumors compared to well and poorly differentiated tumors, p <0.005 and p<0.001, respectively.

Conclusions

The current study shows that MMP-2 and MMP-9 protein expression was significantly higher in the breast cancer than in the fibroadenoma and also in moderately differentiated breast cancer.

Electrochemical impedance spectroscopy for quantization of matrix Metalloproteinase-14 based on peptides inhibiting its homodimerization and heterodimerization

We reported here two novel electrochemical impedance spectroscopy biosensors were developed for the first time for highly sensitive quantification of matrix metalloproteinase-14 (MMP-14) based on binding interaction between hemopexin-like domain (PEX) of MMP-14 (PEX-14) and its inhibitory peptides. Specific inhibitory peptides (IVSC or ISC) inhibiting homodimerization or heterodimerization of MMP-14 was first self assembled on the surface of gold electrode and blocked with 6-mercapto-1-hexanol on a gold electrode surface used as IVSC or ISC modified biosensor, respectively. IVSC modified biosensor can be used for detection of MMP-14 by using the direct IVSC-MMP-14 interaction inhibiting MMP-14 homodimerization as well as ISC modified biosensor for indirect detection of MMP-14 via PEX-14 mediated peptide-MMP-14 binding. The electron transfer resistance (R_et) of biosensor was monitored to measure MMP-14 using Fe(CN)₆^3-/4- as probe. The increase of the R_et of the biosensors are linear with the concentration of MMP-14 in the range from 1 μg L^-1 to 10 μg L^-1 with detection limit of 0.19 μg L^-1 for IVSC modified biosensor and 0.1 ng L^-1 to 50 ng L^-1 with detection limit of 7 ng L^-1 for ISC modified biosensor. This work demonstrates that probing the interaction between peptide inhibitor and PEX of MMPs represents a novel approach to assess MMPs-mediated cancer dissemination.

Leptin induces cell migration and invasion in a FAK-Src-dependent manner in breast cancer cells

Breast cancer is the most common invasive neoplasia, and the second leading cause of the cancer deaths in women worldwide. Mammary tumorigenesis is severely linked to obesity, one potential connection is leptin. Leptin is a hormone secreted by adipocytes, which contributes to the progression of breast cancer. Cell migration, metalloproteases secretion, and invasion are cellular processes associated with various stages of metastasis. These processes are regulated by the kinases FAK and Src. In this study, we utilized the breast cancer cell lines MCF7 and MDA-MB-231 to determine the effect of leptin on FAK and Src kinases activation, cell migration, metalloprotease secretion, and invasion. We found that leptin activates FAK and Src and induces the localization of FAK to the focal adhesions. Interestingly, leptin promotes the activation of FAK through a Src- and STAT3-dependent canonical pathway. Specific inhibitors of FAK, Src and STAT3 showed that the effect exerted by leptin in cell migration in breast cancer cells is dependent on these proteins. Moreover, we established that leptin promotes the secretion of the extracellular matrix remodelers, MMP-2 and MMP-9 and invasion in a FAK and Src-dependent manner. Our findings strongly suggest that leptin promotes the development of a more aggressive invasive phenotype in mammary cancer cells.

Metalloproteinases and their roles in human cancer

It is now widely appreciated that members of the matrix metalloproteinase (MMP) family of enzymes play a key role in cancer development and progression along with many of the hallmarks associated with them. The activity of these enzymes has been directly implicated in extracellular matrix remodeling, the processing of growth factors and receptors, the modulation of cell migration, proliferation, and invasion, the epithelial to mesenchymal transition, the regulation of immune responses, and the control of angiogenesis. Certain MMP family members have been validated as biomarkers of a variety of human cancers including those of the breast, brain, pancreas, prostate, ovary, and others. The related metalloproteinases, the A disintegrin and metalloproteinases (ADAMs), share a number of these functions as well. Here, we explore these essential metalloproteinases and some of their disease-associated activities in detail as well as some of their complementary translational potential. Anat Rec, 2019. © 2019 Wiley Periodicals, Inc.

Evaluation of Cyclosaplin Efficacy Using a Silk Based 3D Tumor Model

Development of novel anti-cancer peptides requires a rapid screening process which can be accelerated by using appropriate in vitro tumor models. Breast carcinoma tissue is a three-dimensional (3D) microenvironment, which contains a hypoxic center surrounded by dense proliferative tissue. Biochemical clues provided by such a 3D cell mass cannot be recapitulated in conventional 2D culture systems. In this experiment, we evaluate the efficacy of the sandalwood peptide, cyclosaplin, on an established in vitro 3D silk breast cancer model using the invasive MDA-MB-231 cell line. The anti-proliferative effect of the peptide on the 3D silk tumor model is monitored by alamarBlue assay, with conventional 2D culture as control. The proliferation rate, glucose consumed, lactate dehydrogenase (LDH), and matrix metalloproteinase 9 (MMP-9) activity of human breast cancer cells are higher in 3D constructs compared to 2D. A higher concentration of drug is required to achieve 50% cell death in 3D culture than in 2D culture. The cyclosaplin treated MDA-MB-231 cells showed a significant decrease in MMP-9 activity in 3D constructs. Microscopic analysis revealed the formation of cell clusters evenly distributed in the scaffolds. The drug treated cells were less in number, smaller and showed unusual morphology. Overall, these findings indicate the role of cyclosaplin as a promising anti-cancer therapeutic.

A Systematic Investigation of the Malignant Functions and Diagnostic Potential of the Cancer Secretome

The collection of proteins secreted from a cell-the secretome-is of particular interest in cancer pathophysiology due to its diagnostic potential and role in tumorigenesis. However, cancer secretome studies are often limited to one tissue or cancer type or focus on biomarker prediction without exploring the associated functions. We therefore conducted a pan-cancer analysis of secretome gene expression changes to identify candidate diagnostic biomarkers and to investigate the underlying biological function of these changes. Using transcriptomic data spanning 32 cancer types and 30 healthy tissues, we quantified the relative diagnostic potential of secretome proteins for each cancer. Furthermore, we offer a potential mechanism by which cancer cells relieve secretory pathway stress by decreasing the expression of tissue-specific genes, thereby facilitating the secretion of proteins promoting invasion and proliferation. These results provide a more systematic understanding of the cancer secretome, facilitating its use in diagnostics and its targeting for therapeutic development.

Prognostic significance of plasma matrix metalloprotease-2 in pancreatic cancer patients

Background & objectives:

Pancreatic cancer has a propensity for wide stromal invasion. Matrix metalloprotease-2 (MMP-2) is a protease that degrades the peri-tumoural tissue and helps in tumour dissemination. Thus, this study was aimed to assess any association of plasma MMP-2 levels with clinicopathological parameters and survival of patients with pancreatic cancer.

Methods:

Plasma samples from 127 pancreatic cancer patients were analyzed for MMP-2 levels by ELISA. Survival and other clinicopathological parameters of patients were analyzed for any correlation with plasma MMP-2 levels.

Results:

The mean MMP-2 levels in pancreatic cancer patients were 560.3±222.0 ng/ml which were significantly elevated compared to chronic pancreatitis patients (P<0.001) and healthy individuals (P<0.05). The plasma levels of MMP-2 significantly correlated with tissue expression of this protease (P=0.004). However, MMP-2 levels did not exhibit any association either with clinicopathological parameters or with survival.

Interpretation & conclusions:

Elevated MMP-2 levels were observed in blood of pancreatic cancer patients which correlated with its tissue expression. However, these levels did not associate with survival or any clinicopathological parameters of patients. Further studies need to be done to confirm the prognostic/clinical significance of MMP-2 in cancer patients before and after surgery.

AIMP2-DX2 Promotes the Proliferation, Migration, and Invasion of Nasopharyngeal Carcinoma Cells

Nasopharyngeal carcinoma (NPC) is a head and neck tumor with high degree of malignancy and with high incidence especially in southern China. AIMP2-DX2, one isoform of the aminoacyl-tRNA synthetase interacting multifunctional proteins (AIMPs), is shown to be a potential target in many cancers. However, the detailed mechanisms of AIMP2-DX2 in NPC development remain to be elucidated. Here, we found that the mRNA expression level of AIMP2-DX2 was significantly increased in NPC specimens, compared with normal nasopharyngeal tissues. Microarray immunohistochemical analysis of NPC specimens and Kaplan–Meier analysis showed that patients with high AIMP2-DX2 protein expression had shorter overall survival than those with low AIMP2-DX2 level. Furthermore, mRNA and protein expression levels of AIMP2-DX2 were both increased in cultured NPC cell lines (5-8F, CNE-2Z, and CNE-1), by being compared with normal nasopharyngeal cell line NP69. Overexpression of AIMP2-DX2 remarkably promoted the cell viability, cell migration, and invasion of cultured NPC cells. Genetic knockdown of AIMP2-DX2 by shRNA lentiviruses significantly suppressed the proliferation, migration, and invasion and induced apoptosis of NPC cells. Inhibition of AIMP2-DX2 decreased the highly expressed level of matrix metalloproteinase- (MMP-) 2 and MMP-9, further suppressed proliferation, migration, and invasion in cultured NPC cells in vitro, and inhibited tumor growth in a xenograft mouse model in vivo. Taken together, these results suggest that AIMP2-DX2 plays an important role in the regulation of NPC and could be a potential therapeutic target and prognostic indicator for the treatment of NPC.

Circulating tumor cells and serum levels of MMP-2, MMP-9 and VEGF as markers of the metastatic process in patients with high risk of metastatic progression

BACKGROUND AND AIMS

Metastases are a severe complication in cancer patients and biomarkers predicting their progression are still lacking for specific groups of patients. HER2 positive breast cancer (HER2 BC) patients on trastuzumab therapy are at risk of the development of unpredictable and often fatal central nervous system (CNS) metastases and castration resistant prostate cancer (CRPC) patients urgently need a marker of disease progression during therapy. Proposed metastatic markers: circulating tumor cells (CTC), serum levels of matrix metalloproteinase 2 (MMP-2), 9 (MMP-9) and vascular endothelial growth factor (VEGF) were prospectively studied to confirm their utility in these two narrowly defined groups of cancer patients.

PATIENTS AND METHODS

The groups comprised 44 advanced HER2 BC, 24 CRPC patients and 42 healthy controls. An immunomagnetic separation method followed by PCR and electrophoretic detection (AdnaGen, Germany) were used for CTC determination. Serum marker levels were determined by the ELISAs (R&D System, USA).

RESULTS

MMP-2 serum level was significantly higher in HER2 BC patients who developed CNS metastases, especially if there were also bone metastases. CTCs were a negative predictive marker for overall survival in HER2 BC patients. MMP-9 serum level was significantly higher in CRPC patients in whom disease progression occurred. CTC vanished from the blood of most of the CRPC patients (from 88% to 37%) during chemotherapy.

CONCLUSION

MMP-2 serum level and CTCs show the potential to predict CNS metastases and overall survival in BC patients. CTCs and MMP-9 serum level could be a promising therapy response marker in CRPC patients.

DRP5 is involved in cancer cell growth and predicts poor prognosis in human osteosarcoma

Osteosarcoma is an extremely aggressive primary malignant bone tumor of childhood. Collapsin response mediator proteins (CRMPs), which are highly expressed in the developing nervous system, were recently shown to be associated with cancer development. However, the relationship between DRP5 (CRMP5) and osteosarcoma has not been evaluated. In this study, we investigated the role of DRP5 in the regulation of osteosarcoma growth. DRP5 mRNA and protein levels were significantly upregulated in human osteosarcoma cell lines and associated with increased migration and invasion. Genetic knockdown of DRP5 markedly suppressed the expression of matrix metalloproteinase (MMP)‐2 and MMP‐9. DRP5 silencing significantly inhibited osteosarcoma cell growth in vitro and in a xenograft mouse model in vivo. Microarray immunohistochemical analysis of osteosarcoma specimens and Kaplan–Meier analysis showed that patients with high DRP5 protein expression had shorter overall survival than those with low DRP5 levels. Taken together, these results suggest that DRP5 plays a critical role in the regulation of osteosarcoma and could be a potential therapeutic target and prognostic factor in osteosarcoma.

Protease Activity and Cell-Free DNA in Blood Plasma of Healthy Donors and Breast Cancer Patients

Tumor development is generally accompanied by increased protease activity and cell-free DNA (cfDNA) levels in the blood. An immunoassay for protease activity was developed based on the binding of anti-peptide antibodies onto polystyrene plates, followed by incubation with peptides and protein hydrolyzing enzymes. The data obtained demonstrate the peptide CD34-1 composed of uncharged amino acids was the best substrate for the estimation of plasma protease activity in breast cancer patients and healthy donors. Anti-CD34-1 peptide protease activity was shown to correlate with circulating DNA concentrations in cancer patients and healthy subjects (P = 0.001, r = 0.676), demonstrating the role of protease activity in the regulation of cfDNA levels.

Long form collapsin response mediator protein-1 promotes the migration and invasion of osteosarcoma cells

It has been reported that long form collapsin response mediator protein-1 (LCRMP-1) promotes the metastasis of non-small cell lung cancer. Osteosarcoma (OS) is a human cancer with a high potential for metastasis. The present study aimed to investigate the role of LCRMP-1 in OS metastasis. The expression of LCRMP-1 in OS specimens and cell lines was evaluated using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis. Furthermore, the migration and invasion of OS cells with LCRMP-1-knockdown was investigated to examine the role of LCRMP-1 in OS metastasis. In addition, the expression of N-cadherin and matrix metalloproteinases (MMPs), which are involved in cell migration, was evaluated using RT-qPCR. Increased expression of LCRMP-1 was observed in the OS tissues and cell lines, accompanied by the enhanced migration and invasion of the OS cells. LCRMP-1-knockdown resulted in a significant decrease in the expression of N-cadherin and MMPs, as well as inhibition of the migration and invasion of the OS cells. Overexpression of LCRMP-1 promoted OS metastasis. Therefore, LCRMP-1 may be a promising target for the effective treatment of OS.

A reduced graphene oxide-based fluorescence resonance energy transfer sensor for highly sensitive detection of matrix metalloproteinase 2

A novel fluorescence nanoprobe (reduced nano-graphene oxide [nrGO]/fluorescein isothiocyanate-labeled peptide [Pep-FITC]) for ultrasensitive detection of matrix metalloproteinase 2 (MMP2) has been developed by engineering the Pep-FITC comprising the specific MMP2 substrate domain (PLGVR) onto the surface of nrGO particles through non-covalent linkage. The nrGO was obtained by water bathing nano-graphene oxide under 90°C for 4 hours. After mixing the nrGO and Pep-FITC for 30 seconds, the fluorescence from Pep-FITC was almost completely quenched due to the fluorescence resonance energy transfer between fluorescein isothiocyanate (FITC) and nrGO. Upon cleavage of the amide bond between Leu and Gly in the Pep-FITC by protease-MMP2, the FITC bound to nrGO was separated from nrGO surface, disrupting the fluorescence resonance energy transfer process and resulting in fluorescence recovery of FITC. Under optimal conditions, the fluorescence recovery of nrGO/Pep-FITC was found to be directly proportional to the concentration of MMP2 within 0.02–0.1 nM. The detection limit of the nrGO/Pep-FITC was determined to be 3 pM, which is approximately tenfold lower than that of the unreduced carboxylated nano-graphene oxide/Pep-FITC probe.

An electrochemical peptide cleavage-based biosensor for matrix metalloproteinase-2 detection with exonuclease III-assisted cycling signal amplification

In this work, an electrochemical peptide biosensor was developed for matrix metalloproteinase-2 (MMP-2) detection by conversion of a peptide cleavage event into DNA detection with exonuclease III (Exo III)-assisted cycling signal amplification.

Matrix metalloproteinases as breast cancer drivers and therapeutic targets

Members of the matrix metalloproteinase (MMP) family have been identified as poor prognosis markers for breast cancer patients and as drivers of many facets of the tumor phenotype in experimental models. Early enthusiasm for MMPs as therapeutic targets was tempered following disappointing clinical trials that utilized broad spectrum, small molecule catalytic site inhibitors. However, subsequent research has continued to define key roles for MMPs as breast cancer promoters, to elucidate the complex roles that that these proteins play in breast cancer development and progression, and to identify how these roles are linked to specific and unique biochemical features of individual members of the MMP family. Here, we provide an overview of the structural features of the MMPs, then discuss clinical studies identifying which MMP family members are linked with breast cancer development and new experimental studies that reveal how these specific MMPs may play unique roles in the breast cancer microenvironment. We conclude with a discussion of the most promising avenues for development of therapeutic agents capable of targeting the tumor-promoting properties of MMPs.

Plasma matrix metalloproteinase 2 levels and breast cancer risk

Matrix metalloproteinase 2 (MMP2) is an enzyme with important functions in breast cancer invasion and metastasis. However, it is unclear whether circulating MMP2 levels may predict breast cancer risk. We conducted a prospective nested case-control analysis in the Nurses' Health Study among 1136 cases who were diagnosed with invasive breast cancer between 1992 and 2004 and 1136 matched controls. All participants provided blood samples in 1989-1990, and a subset (170 cases, 170 controls) contributed an additional sample in 2000-2002. Pre-diagnostic plasma MMP2 levels were measured via immunoassay, and conditional logistic regression was performed to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs), adjusted for breast cancer risk factors. No association was observed between plasma MMP2 levels and risk of total invasive breast cancer (top vs. bottom quartile, OR=1.0; 95% CI: 0.7, 1.2; p-trend=0.89). Findings did not vary significantly by time since blood draw, body mass index, postmenopausal hormone use, or menopausal status at either blood draw or breast cancer diagnosis. MMP2 was associated with a greater risk of nodal metastases at diagnosis (top vs. bottom quartile, OR=1.5; 95% CI: 1.0, 2.2; p-heterogeneity, any vs. no lymph nodes=0.002), but no significant associations were observed with other tumor characteristics or with recurrent or fatal cancers. Plasma MMP2 levels do not appear to be predictive of total invasive breast cancer risk, although associations with aggressive disease warrant further study.

A ‘signal on-off’ electrochemical peptide biosensor for matrix metalloproteinase 2 based on target induced cleavage of a peptide

A sensitive ‘signal on–off’ electrochemical peptide biosensor for MMP-2 assay was fabricated based on target induced cleavage of a specific peptide.

Ultrasensitive photoelectrochemical immunoassay for matrix metalloproteinase-2 detection based on CdS:Mn/CdTe cosensitized TiO2 nanotubes and signal amplification of SiO2@Ab2 conjugates

An ultrasensitive photoelectrochemical sandwich immunoassay was developed to detect matrix metalloproteinase-2 (MMP-2, antigen, Ag) based on CdS:Mn/CdTe cosensitized TiO2 nanotubes (TiO2-NTs) and signal amplification of SiO2@Ab2 conjugates. Specifically, the TiO2-NTs electrode was first deposited with CdS:Mn by successive ionic layer adsorption and reaction technique and then further coated with CdTe quantum dots (QDs) via the layer-by-layer method, forming TiO2-NTs/CdS:Mn/CdTe cosensitized structure, which was employed as a matrix to immobilize capture MMP-2 antibodies (Ab1); whereas, SiO2 nanoparticles were coated with signal MMP-2 antibodies (Ab2) to form SiO2@Ab2 conjugates, which were used as signal amplification elements via the specific antibody-antigen immunoreaction between Ag and Ab2. The ultrahigh sensitivity of this immunoassay derived from the two major reasons as below. First, the TiO2-NTs/CdS:Mn/CdTe cosensitized structure could adequately absorb the light energy, dramatically promote electron transfer, and effectively inhibit the electron-hole recombination, resulting in significantly enhanced photocurrent intensity of the sensing electrode. However, in the presence of target Ag, the immobilized SiO2@Ab2 conjugates could evidently increase the steric hindrance of the sensing electrode and effectively depress the electron transfer, leading to obviously decreased photocurrent intensity. Accordingly, the well-designed photoelectrochemical immunoassay exhibited a low detection limit of 3.6 fg/mL and a wide linear range from 10 fg/mL to 500 pg/mL for target Ag detection. Meanwhile, it also presented good reproducibility, specificity, and stability and might open a new promising platform for the detection of other important biomarkers.

Expression and correlation of matrix metalloproteinase-9 and heparanase in patients with breast cancer

Matrix metalloproteinase-9 (MMP-9) and heparanase (HPSE) are thought to be involved in tumor progression and metastasis. However, up to now, there are no studies that simultaneously investigated the expression levels of MMP-9 and HPSE in tumor tissue and serum of breast cancer patients. Their correlation in breast cancer pathological processes is unknown. The purpose of this study was to investigate the expression profile of MMP-9 and HPSE in breast cancer and to assess their clinicopathological significance. We measured serum MMP-9 and HPSE by enzyme-linked immunosorbent assay in healthy women, and in patients with benign and malignant breast disease. We also evaluated the expression of MMP-9 and HPSE protein in paraffin-embedded tumor tissues by immunohistochemistry. We then correlated serum and tissue levels of MMP-9 and HPSE in breast cancer samples and their expression with patients' clinicopathologic characteristics. We found that serum levels of MMP-9 and HPSE were significantly higher in breast cancer patients than in benign breast disease and in healthy controls (P = 0.001). There was positive correlation between MMP-9 and HPSE in breast cancer patients. The tissue and serum levels of MMP-9 were associated with histology grade, lymph node status, pathological stage, and lymphovascular invasion (all P < 0.05). The tissue levels of MMP-9 were also associated with ER (P = 0.038) and Ki-67 (P = 0.032). The tissue and serum levels of HPSE expression were associated with tumor size, histology grade, lymph node status, and pathological stage (all P < 0.05). Our findings suggested that MMP-9 and HPSE might further be evaluated as biomarkers for predicting progression and prognosis of breast cancer.

Matrix metalloproteinase 9 (MMP-9) in osteosarcoma: review and meta-analysis

The aim of this study is to determine the value of matrix metalloproteinase 9 (MMP-9) in diagnosis of osteosarcoma (OS). A systematic review and meta-analysis was conducted using MEDLINE, Embase, ISI Web of Knowledge, the Cochrane Library, Scopus, BioMed Central, ScienceDirect, China Biomedical literature Database (CBM) and China National Knowledge Internet (CNKI) from inception through Aug 29, 2013. Articles written in English or Chinese that investigated the accuracy of MMP-9 for the diagnosis of OS were included. Pooled sensitivity, specificity and the area under the receiver operating characteristic curve (AUC) were determined. I(2) was used to test heterogeneity and source of heterogeneity was investigated by meta-regression (tested with Meta-DiSc and STATA 12.0 statistical softwares). A total of 3729 articles were retrieved, of which 18 were included, accounting for 892 patients. Overall, the pooled sensitivity, specificity and AUC were 0.78 (95% CI 0.730-0.83), 0.90 (95% CI 0.79-0.95), and 0.87 (95% CI 0.83-0.89), respectively. The studies had substantial heterogeneity (I(2)=84%, 95% CI 65-100) (96%, 95% CI 94-99). Assay kit subgroup was the main source of the heterogeneity. Although MMP-9 was identified as a potential biomarker for OS, more studies were clearly needed to establish its diagnostic value.

The value of MMP-9 for breast and non-small cell lung cancer patients' survival

PURPOSE

Matrix metalloproteinases (MMPs) are implicated in cancer cells invasion and metastasis processes and have been investigated as potential cancer biomarkers. In this study MMP-9 gene expression and MMP-9 -1562 C/T polymorphism in breast and non-small cell lung cancer patients' blood and tumor samples and its correlation with clinicopathological parameters were investigated.

MATERIAL/METHODS

MMP-9 gene expression was assessed by reverse transcription - polymerase chain reaction method in 108 cancer patients' blood and tumor samples. MMP-9 -1562 C/T polymorphism was determined by the polymerase chain reaction - based restriction fragment length polymorphism method.

RESULTS

Significant relationship of MMP-9 gene expression and tumor differentiation grade was found only between groups with G1 and G3 breast tumors. Low survival rates were identified among positive MMP-9 expression in blood and ductal carcinoma of the breast (p=0.01) and negative progesterone receptor reaction (p=0.04). Significant differences in the distribution among genotypes were found between groups with stage I and stages III/IV (p=0.005) as well as between groups with lymph node status N0 and N1 (p<0.001). Breast cancer patients with tumor differentiation grade G3 and identified CC variant had a longer survival time (p=0.014). Shorter survival time was found among positive MMP-9 expression in tumor and stage I non-small cell lung cancer patients with negative lymph node (p=0.012) and squamous cell carcinoma (p=0.019).

CONCLUSIONS

Expression of MMP-9 in blood and tumor together indicates worse prognosis for breast cancer patients.