Overexpression of matrix metalloproteinases and their inhibitors in mononuclear inflammatory cells in breast cancer correlates with metastasis-relapse

Gastric cancer - The role of matrix metalloproteinases in tumor progression

Gastric cancer (GC) is a very aggressive malignant tumor of gastrointestinal tract due to its invasive nature and early metastatic ability. Degradation of the extracellular matrix (ECM) and basement membrane (BM) barriers are essential steps in the pathology of GC. Matrix metalloproteinases (MMPs) play a crucial role in the process due to their ability to degrade and rearrange these barriers to support and facilitate tumor cell migration. Therefore, these enzymes affect early carcinogenesis, tumor development and growth as well as the invasion of cancer cells at primary and metastatic sites. The endogenous inhibitors of matrix metalloproteinases (TIMPs) inhibit the active forms of MMPs and regulate the processes of their activation. The imbalance between MMPs and TIMPs may facilitate the progression of neoplastic cells. The enhanced levels of various MMPs and TIMPs have been observed in the tissue, plasma and serum of patients with many types of tumor, including gastric cancer. Moreover, levels of MMPs and TIMPs in the tissues as well as in the blood of GC patients correlated with tumor stage, depth of tumor invasion, presence of nodal and distant metastases. Selected MMPs and their tissue inhibitors were proved to be independent prognostic factors for GC patients' survival. However, further studies concerning the role of MMPs and their inhibitors in tumor biology are necessary.

Comparative analysis and clinical value of the expression of metalloproteases and their inhibitors by intratumour stromal mononuclear inflammatory cells and those at the invasive front of breast carcinomas

AIMS

Matrix metalloproteases (MMPs) and their inhibitors (TIMPs) play an essential role in the degradation of stromal connective tissue and basement membrane components. The aim of this study was to determine whether the dynamic analysis of these components can help to predict tumour aggressiveness.

METHODS AND RESULTS

An immunohistochemical study was performed using tissue arrays and specific antibodies against MMPs -1, -2, -7, -9, -11, -13 and -14 and TIMPs -1, -2 and -3. More than 5000 determinations on cancer specimens from 124 patients with invasive breast cancer were performed on the tumour centre core as well as on the invasive front. Immunostaining for MMPs/TIMPs on mononuclear inflammatory cells (MICs) was evaluated. To identify specific groups of tumours with distinct expression profiles, data obtained from both MICs populations were analysed by unsupervised hierarchical cluster analysis. When compared with MICs at the invasive front, intratumour MICs more frequently showed expression of MMP-7 and -1 and TIMP-3, but less frequently expression of MMP-9 and -11 and TIMP-2.

CONCLUSIONS

Our data led us to consider the need of further studies in order to identify subsets of MICs and other protein elements of the microenvironment as attractive targets for new therapeutic strategies against cancer.

Study of TLR3, TLR4 and TLR9 in breast carcinomas and their association with metastasis

Background

Toll-like receptors (TLRs) have garnered an extraordinary amount of interest in cancer research due to their role in tumor progression. By activating the production of several biological factors, TLRs induce type I interferons and other cytokines, which drive an inflammatory response and activate the adaptive immune system. The aim of this study was to investigate the expression and clinical relevance of TLR3, 4 and 9 in breast cancer.

Methods

The expression levels of TLR3, TLR4 and TLR9 were analyzed on tumors from 74 patients with breast cancer. The analysis was performed by immunohistochemistry.

Results

Samples of carcinomas with recurrence exhibited a significant increase in the mRNA levels of TLR3, TLR4 and TLR9. Tumors showed high expression of TLRs expression levels by cancer cells, especially TLR4 and 9. Nevertheless, a significant percentage of tumors also showed TLR4 expression by mononuclear inflammatory cells (21.6%) and TLR9 expression by fibroblast-like cells (57.5%). Tumors with high TLR3 expression by tumor cell or with high TLR4 expression by mononuclear inflammatory cells were significantly associated with higher probability of metastasis. However, tumours with high TLR9 expression by fibroblast-like cells were associated with low probability of metastasis.

Conclusions

The expression levels of TLR3, TLR4 and TLR9 have clinical interest as indicators of tumor aggressiveness in breast cancer. TLRs may represent therapeutic targets in breast cancer.

Collagenase-3 expression by tumor cells and gelatinase B expression by stromal fibroblast-like cells are associated with biochemical recurrence after radical prostatectomy in patients with prostate cancer

PURPOSE

To investigate the possible clinical value of the expression of MMPs and their tissue inhibitors (TIMPs) by the different cellular types of the tumor scenario to predict biochemical recurrence in patients undergoing radical prostatectomy due clinically localized prostate cancer.

METHODS

An immunohistochemical study was performed using tissue arrays and specific antibodies against MMPs-1, 2, 7, 9, 11, 13 and 14 and TIMPs-1, 2 and 3 on cancer specimens from 133 patients with clinical localized prostate carcinoma.

RESULTS

Immunostaining for all the proteins studied was localized predominantly in tumor cells, but also in stromal cells in a significant percentage of prostate carcinomas, ranged from 20 to 50% for several proteins in fibroblast-like cells and in mononuclear inflammatory cells. Multivariate analysis according to a Cox model demonstrated that tumor stage (P < 0.0001) and Gleason grading (grades 7-10: 2.08 (1.1-3.9); P < 0.05) were significantly and independently associated with biochemical recurrence. Additionally, the expression of MMP-9 by fibroblast-like cells (P < 0.01) and MMP-13 by tumor cells (P < 0.05) were also variables significantly and independently associated with biochemical recurrence.

CONCLUSIONS

MMP-13 expression by tumor cells and MMP-9 by stromal fibroblast-like cells were independent factors of biochemical recurrence in prostate cancer.

Expression of matrix metalloproteinase-9 in the neoplastic and interstitial inflammatory infiltrate cells in gastric cancer

Matrix metalloproteinases (MMPs) play an important role in the extracellular matrix degradation, that is an essential step in tumor invasion and metastases. The current study objective was to evaluate the expression of MMP-9 in the neoplastic and in the interstitial inflammatory infiltrate cells in gastric cancer (GC). Moreover, the relationship between expression of this enzyme and clinicopathological features of GC, such as TNM stage, the depth of tumor invasion, lymph node and distant metastases were assessed. The study comprised 54 patients with gastric cancer. Immunohistochemistry was used to determine the expression of MMP-9 in gastric cancer cells. The semi-quantitative scale was applied to evaluate the expression of metalloproteinase-9. Immunohistochemical testing revealed a positive reaction of MMP-9 in 98% of all cancer tissue specimens and in 93% of inflammatory cells. The expression of MMP-9 in the neoplastic and inflammatory cells increased with more advance tumor stage, depth of tumor invasion and presence of lymph node as well as distant metastases. These findings indicate the significance of interstitial inflammatory infiltrate cells in the MMP-9 synthesis and the role of this enzyme in the invasiveness and metastatic potential of GC.

Comparative study of the expression of metalloproteases and their inhibitors in different localizations within primary tumours and in metastatic lymph nodes of breast cancer

Studies on metastasic lesions from human carcinomas are scarce. Therefore there is a need for such studies to identify the expression of the biological factors that will help in the assessment of the natural history of breast cancer. Here an immunohistochemical study was performed using tissue arrays and specific antibodies against matrix metalloproteinases (MMPs)-1, 2, 7, 9, 11, 13, 14 and tissue inhibitors of metalloproteases (TIMPs)-1, 2 and 3 in 39 patients with breast cancer. Specimens from 39 patients with node-positive carcinomas were examined and the analysis was performed at the central core of the tumour, at the invasive front, and in the metastasic axillary lymph nodes (MALNs). Global expression of MMP-1, 7 and 14, TIMP-1, and 3, were significantly higher at the centre of the tumour compared with the invasive front or the MALNs. Significantly higher expression of MMP-7 and 14, and TIMP-3, by fibroblast-like cells and mononuclear inflammatory cells (MICs) was seen in MALNs. In addition, in the tumour centre, the expression of MMP-11 and TIMP-1 and 2 by MICs, as well as TIMP-2 expression by fibroblast-like cells, were associated significantly with the occurrence of distant metastasis. In contrast, TIMP-3 expression by tumour cells or by fibroblast-like cells in this same tumour locations, as well as TIMP-1 expression by fibroblast-like cells at the invasive front, were associated significantly with poor prognosis. However, the expression of all of these biological factors in MALNs was not associated with the development of distant metastasis. Our data suggest that there is prognostic relevance to the expression of MMPs and TIMPs in the stromal cells of primary tumours, rather than to the expression of these enzymes in MALNs.

Immunohistochemical study of matrix metalloproteinases and their inhibitors in pure and mixed invasive and in situ ductal carcinomas of the breast

We assessed differences in the patterns of expression of matrix metalloproteases and their inhibitors (tissue inhibitors of metalloproteases) in ductal carcinoma in situ alone and admixed with invasive ductal carcinomas (n = 40), as well as in pure invasive ductal carcinomas (n = 40), immunohistochemically and using tissue arrays. The invasive ductal carcinoma components showed higher expression of matrix metalloprotease-9 and -13 than did the admixed ductal carcinoma in situ, whereas stromal fibroblasts of the invasive components showed higher expression of matrix metalloprotease-2, -7, -9, -13, and -14 and tissue inhibitor of metalloprotease-1 and -3 than did fibroblasts around the neoplastic ducts of the admixed ductal carcinoma in situ. Expression of matrix metalloprotease-14 and tissue inhibitor of metalloprotease-3 was significantly higher in the mononuclear inflammatory cells of the invasive components. By contrast, matrix metalloprotease-1 expression was significantly higher in stromal cells of the ductal carcinoma in situ admixed with invasive ductal carcinoma. The pure invasive ductal carcinomas had significantly higher expression of matrix metalloprotease-1, -9, -11, and -14 and tissue inhibitor of metalloprotease-1 and -3 than the invasive ductal carcinomas admixed with ductal carcinoma in situ. Our findings indicate a significant association of matrix metalloprotease expression by the periductal stromal cells of the ductal carcinoma in situ component of mixed tumors and the occurrence of distant metastasis. Our data suggest that the molecular matrix metalloprotease/tissue inhibitor of metalloprotease profile can contribute to better characterization of early breast carcinomas.

Study of matrix metalloproteinases and their inhibitors in prostate cancer

BACKGROUND

Extracellular matrix metalloproteases (MMPs) have raised an extraordinary interest in cancer research because of their potential role in basal membrane and extracellular matrix degradation, consequently facilitating tumour invasion and metastases development.

METHODS

An immunohistochemical study was performed using tissue arrays and specific antibodies against MMPs 1, 2, 7, 9, 11, 13, 14, and their tissue inhibitors, TIMPs 1, 2 and 3. More than 2600 determinations on cancer specimens from 133 patients with clinically localised prostate carcinoma, 20 patients with prostatic intraepithelial neoplasia and 50 patients with benign prostate hyperplasia and controls, were performed.

RESULTS

When compared with benign pathologies, prostate carcinomas had higher expression of all MMPs and TIMPs. Dendogram shows a first-order division of tumours into two distinct MMPs/TIMPs molecular profiles, one of them with high MMPs/TIMs expression profile (n=70; 52.6%). Tumours with high expression of MMP-11 or -13, or cluster thereof, were significantly associated with higher probability of biochemical recurrence.

CONCLUSION

The expression of MMPs and TIMPs seems to have an important role in the molecular biology of prostate carcinomas, and their expression by tumours may be of clinical interest to used as indicators of tumour aggressiveness.

Expression of metalloproteases and their inhibitors by tumor and stromal cells in ductal carcinoma in situ of the breast and their relationship with microinvasive events

AIMS

This study aimed to investigate the expression of matrix metalloproteases (MMPs) and their inhibitors (TIMPs) in ductal carcinoma in situ (DCIS).

METHODS

We used inmunohistochemistry to compare the expression of MMPs and TIMPs in tumor or stromal cells for 50 pure DCIS and 12 DCIS with microinvasive foci.

RESULTS

Score values for collagenase-1 (MMP-1), membrane type 1 MMP (MMP-14), and TIMP-1, were significantly higher in pure DCIS than in DCIS with microinvasive foci, whereas stromalysin-3 (MMP-11) expression was significantly higher in DCIS with microinvasive foci. Both fibroblasts and mononuclear inflammatory cells (MICs) surrounding pure DCIS showed more frequently expression of MMP-1, MMP-14, and TIMP-3, whereas MMP-11 expression was more frequent in MICs of microinvasive tumors. MICs of microinvasive foci more frequently showed the expression of gelatinase A (MMP-2), MMP-11, collagenase-3 (MMP-13), and TIMP-1, than MICs surrounding pure DCIS; whereas peri-ductal MICs and fibroblasts from pure DCIS expressed TIMP-3 more commonly than these cells at microinvasive foci.

CONCLUSIONS

There are significant differences in the expression of MMPs and TIMPs, so in tumor cells and stromal cells, between pure DCIS and DCIS with microinvasive foci. Therefore, these staining patterns might display potential applications as biological markers, such as in evaluating microinvasion in resection specimens of breast tumors.

Predicting anthracycline benefit: have we made any progress?

PURPOSE OF REVIEW

The benefit from anthracycline-based vs. nonanthracycline-based adjuvant therapy is not experienced by all breast cancer patients. Identification of the individuals to derive this benefit may be guided by predictive biomarkers. This review focuses on the search for biomarkers, particularly focusing on the potential roles for HER-2 and/or topoisomerase IIalpha.

RECENT FINDINGS

Clarification of differential sensitivity to anthracyclines is complicated due to disease heterogeneity, complexity of underlying biological pathways, biomarker detection methods and features of study design. Meta-analyses suggest anthracycline benefit is restricted to patients with HER-2 amplified disease. However, diversity within HER-2 positive and HER-2 negative subgroups limits the use of HER-2 status as an independent marker. Certainly, subgroups within HER-2 negative disease have demonstrable incremental benefit from anthracycline-based therapy. Regarding topoisomerase IIalpha, the best method of detection and predictive role remain unclear.

SUMMARY

Although progress has been made in defining breast cancer subgroups and identifying patients with general chemosensitivity, we do not yet have reliable predictive markers for anthracyclines. With current evidence, neither HER-2 status nor topoisomerase IIalpha status can be considered clinically valuable in guiding prescription of anthracyclines. Disease heterogeneity may dictate prediction by tumour profiles, rather than any single marker. These profiles may incorporate a panel of markers, including not only tumour features, such as HER-2 and topoisomerase IIalpha, but also host-determined features, such as stroma and stroma-anthracycline interaction. A new generation of well powered clinical trials that attempt to incorporate breast cancer heterogeneity may bridge the gap between available results and individual patient care.

Relationship between morphological features and kinetic patterns of enhancement of the dynamic breast magnetic resonance imaging and clinico-pathological and biological factors in invasive breast cancer

BACKGROUND

To investigate the relationship between the magnetic resonance imaging (MRI) features of breast cancer and its clinicopathological and biological factors.

METHODS

Dynamic MRI parameters of 68 invasive breast carcinomas were investigated. We also analyzed microvessel density (MVD), estrogen and progesterone receptor status, and expression of p53, HER2, ki67, VEGFR-1 and 2.

RESULTS

Homogeneous enhancement was significantly associated with smaller tumor size (T1: < 2 cm) (p = 0.015). Tumors with irregular or spiculated margins had a significantly higher MVD than tumors with smooth margins (p = 0.038). Tumors showing a maximum enhancement peak at two minutes, or longer, after injecting the contrast, had a significantly higher MVD count than those which reached this point sooner (p = 0.012). The percentage of tumors with vascular invasion or high mitotic index was significantly higher among those showing a low percentage (150%) of enhancement rate (p = 0.016 and p = 0.03, respectively). However, there was a significant and positive association between the mitotic index and the peak of maximum intensity (p = 0.036). Peritumor inflammation was significantly associated with washout curve type III (p = 0.042).

CONCLUSIONS

Variations in the early phase of dynamic MRI seem to be associated with parameters indicatives of tumor aggressiveness in breast cancer.

Expression of metalloproteases and their inhibitors in primary tumors and in local recurrences after mastectomy for breast cancer

AIMS

To investigate the expression of matrix metalloproteases (MMPs) and their inhibitors (TIMPs) in patients who develop local recurrence (LR) after mastectomy.

METHODS

We analyzed the expressions of MMP-1, -2, -7, -9, -11, -13, -14, TIMP-1, -2, and -3, using immunohistochemical techniques, in primary tumors from patients without tumoral recurrence (n = 50), patients who developed distant metastasis (n = 50), and from patients who develop LRs (n = 25). LRs of the latter group were also analyzed for MMPs expression. All the patients underwent mastectomy.

RESULTS

Score values for all MMPs and TIMPs were significantly higher in primary tumors of patients with distant metastasis. Primary tumors from patients with LR have lower expressions of MMPs and TIMPs compared with those from patients who developed distant metastasis, and with patients without recurrence for some MMPs. Remarkably, however, primary tumors from patients with LR showed significantly higher percentage of TIMP-1 and 2 expression in stromal cells compared to primary tumors from patients with distant metastasis or primary tumors from patients without tumoral progression. Furthermore, LRs had significantly higher MMP-9 expression than their corresponding primary tumors.

CONCLUSIONS

Our data indicate differences in MMPs/TIMPs expression between primary tumors of patients with LRs and of those with distant metastasis, both after mastectomy for breast cancer.

Expression of metalloproteases and their inhibitors in different histological types of breast cancer

PURPOSE

Metalloproteases (MMPs) and their tissue inhibitors of metalloproteases (TIMPs) are involved in several key aspects of tumoral growth, invasion and metastasis. The purpose of this study was to characterize on how the different histological types of breast cancer differ in the expression of several components of this enzymatic system.

METHODS

An immunohistochemical study was performed in 50 ductal, 23 lobular, 14 mucinous, 7 tubular, 4 papillary and 5 medullary invasive carcinomas, using tissue arrays and specific antibodies against 7 MMPs and 3 tisullar TIMPs. Staining results were categorized by means of a specific software program (score values).

RESULTS

Carcinomas of the ductal type showed higher score values for MMPs and TIMPs than the other histological types; whereas mucinous carcinomas had lower scores values for expressions of the majority of these proteins. Stromal fibroblasts were more frequently positive for MMP-1, -7 and -13 and TIMP-1 and -3, when present in carcinomas of the ductal type than in other histological types of breast carcinomas. Stromal mononuclear inflammatory cells were more frequently positive for MMP-1 and TIMP-3, but more often negative for MMP-7, -9 and -11, when located in carcinomas of the ductal type than in other histological types of breast carcinomas.

CONCLUSIONS

We found variations in MMP/TIMP expressions among the different histological subtypes of breast carcinomas suggesting differences in their tumor pathophysiology.

Mass spectrometry based proteomics profiling as diagnostic tool in oncology: current status and future perspective

Proteomics analysis has been heralded as a novel tool for identifying new and specific biomarkers that may improve diagnosis and monitoring of various disease states. Recent years have brought a number of proteomics profiling technologies. Although proteomics profiling has resulted in the detection of disease-associated differences and modification of proteins, current proteomics technologies display certain limitations that are hampering the introduction of these new technologies into clinical laboratory diagnostics and routine applications. In this review, we summarize current advances in mass spectrometry based biomarker discovery. The promises and challenges of this new technology are discussed with particular emphasis on diagnostic perspectives of mass-spectrometry based proteomics profiling for malignant diseases.

Immunohistochemical expression of tissue inhibitor of metalloproteinase-1 (TIMP-1) in invasive breast carcinoma

Tissue inhibitor of metalloproteinase-1 (TIMP-1) is a natural inhibitor of matrix metalloproteinases (MMPs). Aim of this study was to assess the immunohistochemical expression of TIMP-1 in invasive breast carcinomas, and to examine its association with classical clinico-pathological parameters, oestrogen receptor, progesterone receptor and Her-2/neu protein expression. Immunohistochemistry was used to determine the expression of TIMP-1 on 38 paraffin-embedded breast tissue specimens - 18 with invasive ductal carcinoma, 10 with invasive lobular carcinoma, and 10 specimens from patients with fibrocystic breast disease. TIMP-1 protein was immunodetected in the carcinoma cells, fibroblasts and inflammatory cells of the stroma in 92,9%, 65,8%, and 65,8% of cases, respectively. TIMP-1 protein expression in carcinoma cells showed positive correlation with TIMP-1 protein expression in peritumoural fibroblasts (p=0,010). Positive peritumoural fibroblast TIMP-1 expression was associated with histological tumour type with higher frequency in ductal carcinomas (p=0,023). Negative association was found between TIMP-1 protein expression in carcinoma cells and HER-2/neu nuclear staining (p=0,005). TIMP-1 may be particularly useful as a predictive marker in breast carcinoma when evaluated along with HER-2/neu protein being a promising indicator of favourable prognosis in breast carcinoma.

Expression and prognostic significance of metalloproteases and their inhibitors in luminal A and basal-like phenotypes of breast carcinoma

To analyze the expression and prognostic value of matrix metalloproteases and their tissue inhibitors in luminal A and basal-like breast carcinomas, an immunohistochemical study was performed on cancer specimens from 93 randomly selected patients with invasive primary ductal tumors of the breast (46 with and 47 without distant metastasis) and with luminal A (n = 48) (ER+, HER2-) or basal-like (HER2-, ER-, PgR-) (n = 45) lesions. Luminal B cases were too few to analyze. Specimens were also studied using tissue microarrays and specific antibodies against matrix metalloproteases 1, 2, 7, 9, 11, 13, and 14 and tissue inhibitors 1, 2, and 3. There were no significant differences in matrix metalloprotease or tissue inhibitor expression in the 2 phenotypes of tumors. In basal-like carcinomas, high scores for matrix metalloproteases 9 and 11 were significantly associated with a high distant metastasis rate. Likewise, data showed associations between matrix metalloprotease/tissue inhibitor expression by either stromal fibroblasts or mononuclear inflammatory cells and distant relapse-free survival in both tumor phenotypes. In addition, in infiltrating luminal A and basal-like tumors, we identified a prometastatic phenotype of mononuclear inflammatory cells, showing a high matrix metalloprotease/tissue inhibitor molecular profile. Expression of matrix metalloproteases and tissue inhibitors is related to the characteristics of breast tumor cells. As prognostic factors in breast carcinomas of both luminal A and basal-like phenotypes, our results point to the importance of the expression of matrix metalloproteases and tissue inhibitors by the stromal cells.

Involvement of matrix metalloproteinase 2 and 9 in gambogic acid induced suppression of MDA-MB-435 human breast carcinoma cell lung metastasis

Cancer cell invasion is one of the crucial events in local spreading, growth, and metastasis of tumors. The present study investigated the antiinvasive and antimetastatic action of gambogic acid (GA) in MDA-MB-435 human breast carcinoma cells. GA caused a concentration-dependent suppression of cell invasion through Matrigel and significantly inhibited lung metastases of the cells transplanted in vivo. The potent effects of GA have been attributed to its ability to reduce the expression of matrix metalloproteinases (MMP) 2 and 9 in vitro and in vivo both at the protein and mRNA levels, which were associated with protein kinase C (PKC) signaling pathway as supported by the diminished antiinvasive effect of GA in the presence of specific activator of the pathway. Collectively, our data demonstrated that GA exhibited antiinvasion properties on highly invasive cancer cells via PKC mediated MMP-2/9 expression inhibition. This indicated that GA can be served as a potential novel therapeutic candidate for the treatment of cancer metastasis.

Androgen receptor expresion in breast cancer: relationship with clinicopathological characteristics of the tumors, prognosis, and expression of metalloproteases and their inhibitors

Background

In the present study we analyze, in patients with breast cancer, the tumor expression of androgen receptors (AR), its relationship with clinicopathological characteristics and with the expression of several matrix metalloproteases (MMPs) and their inhibitors (TIMPs), as well as with prognosis.

Methods

An immunohistochemical study was performed using tissue microarrays and specific antibodies against AR, MMPs -1, -2, -7, -9, -11, -13, -14, and TIMPs -1, -2 and -3. More than 2,800 determinations on tumor specimens from 111 patients with primary invasive ductal carcinoma of the breast (52 with axillary lymph node metastases and 59 without them) and controls were performed. Staining results were categorized using a score based on the intensity of the staining and a specific software program calculated the percentage of immunostained cells automatically.

Results

A total of 83 cases (74.8%) showed a positive immunostaining for AR, but with a wide variation in the staining score values. There were no significant associations between the total immunostaining scores for AR and any clinicopathological parameters. However, score values for MMP-1, -7 and -13, were significantly higher in AR-positive tumors than in AR-negative tumors. Likewise, when we considered the cellular type expressing each factor, we found that AR-positive tumors had a higher percentage of cases positive for MMP-1, -7, -11, and TIMP-2 in their malignant cells, as well as for MMP-1 in intratumoral fibroblasts. On the other hand, multivariate analysis demonstrated that patients with AR-positive tumors have a significant longer overall survival than those with AR-negative breast carcinomas (p = 0.03).

Conclusion

Our results confirm that AR are commonly expressed in breast cancer, and are correlated with the expression of some MMPs and TIMP-2. Although we found a specific value of AR expression to be a prognostic indicator in breast cancer, the functional role of AR in these neoplasms is still unclear and further data are needed in order to clarify their biological signification in breast cancer.

Inflammation and breast cancer: metalloproteinases as common effectors of inflammation and extracellular matrix breakdown in breast cancer

Two rapidly evolving fields are converging to impact breast cancer: one has identified novel substrates of metalloproteinases that alter immune cell function, and the other has revealed a role for inflammation in human cancers. Evidence now shows that the mechanisms underlying these two fields interact in the context of breast cancer, providing new opportunities to understand this disease and uncover novel therapeutic strategies. The metalloproteinase class of enzymes is well studied in mammary gland development and physiology, but mostly in the context of extracellular matrix modification. Aberrant metalloproteinase expression has also been implicated in breast cancer progression, where these genes act as tumor modifiers. Here, we review how the metalloproteinase axis impacts mammary physiology and tumorigenesis and is associated with inflammatory cell influx in human breast cancer, and evaluate its potential as a regulator of inflammation in the mammary gland.