Tumor-Biological Factors Upa and PAI-1 as Stratification Criteria of a Multicenter Adjuvant Chemotherapy Trial in Node-Negative Breast Cancer

Is the Urokinase-type Plasminogen Activator System a Reliable Prognostic Factor in Gastric Cancer?

Aim

The aim of this prospective study was to evaluate the clinical and prognostic impact of immunohisto-chemically assessed uPA and PAI-1 in patients with gastric cancer.

Methods

This prospective study analyzed specimens obtained from 105 gastric cancer patients who underwent gastrectomy with extended lymphadenectomy. The immunohistochemical expression of uPA and PAI-1 was studied semiquantitatively in the tumor epithelium and was correlated with the clinicopathological features of each patient.

Results

Univariate analysis revealed no statistically significant association of uPA levels with pT and pN category (p=0.655 and 0.053, respectively), grading (p=0.374), depth of tumor invasion (p=0.665), UICC classification (p=0.21) and the Laurén classification (p=0.578). PAI-1 expression showed no statistically significant correlation with pT, pN and M category (p=0.589, 0.414, and 0.167, respectively), grading (p=0.273), and the Laurén classification (p=0.368). Only the UICC classification was significantly correlated with PAI-1 (p=0.016). Kaplan-Meier analysis revealed no significant association of uPA and PAI-1 with overall survival (p=0.0929 and 0.0870, respectively).

Conclusions

Our results could not verify any prognostic value of uPA and PAI-1 levels in patients with gastric carcinoma. Therefore, the uPA-system as a biologically defined prognostic marker to identify high-risk gastric cancers should be applied with caution. However, considering the number of patients involved and the borderline level of significance observed in this study, a larger number of events may have resulted in significant differences.

Plasminogen Activator System and Breast Cancer: Potential Role in Therapy Decision Making and Precision Medicine

Shifting from the historical TNM paradigm to the determination of molecular and genetic subtypes of tumors has been a major improvement to better picture cancerous diseases. The sharper the picture is, the better will be the possibility to develop subsequent strategies, thus achieving higher efficacy and prolonged survival eventually. Recent studies suggest that urokinase-type plasminogen activator (uPA), uPA Receptor (uPAR), and plasmino-gen activator inhibitor-1 (PAI-1) may play a critical role in cancer invasion and metastasis. Consistent with their role in cancer dissemination, high levels of uPA, PAI-1, and uPAR in multiple cancer types correlate with dismal prognosis. In this respect, upfront determination of uPA and PAI-1 as invasion markers has further opened up the possibilities for individualized therapy of breast cancer. Indeed, uPA and PAI-1 could help to classify patients on their risk for metastatic spreading and subsequent relapse, thus helping clinicians in their decision-making process to propose, or not propose, adjuvant therapy. This review covers the implications for cancer diagnosis, prognosis, and therapy of uPA and PAI-1, and therefore how they could be major actors in the development of a precision medicine in breast cancer.

Identification of selective cytotoxic and synthetic lethal drug responses in triple negative breast cancer cells

Background

Triple negative breast cancer (TNBC) is a highly heterogeneous and aggressive type of cancer that lacks effective targeted therapy. Despite detailed molecular profiling, no targeted therapy has been established. Hence, with the aim of gaining deeper understanding of the functional differences of TNBC subtypes and how that may relate to potential novel therapeutic strategies, we studied comprehensive anticancer-agent responses among a panel of TNBC cell lines.

Method

The responses of 301 approved and investigational oncology compounds were measured in 16 TNBC cell lines applying a functional profiling approach. To go beyond the standard drug viability effect profiling, which has been used in most chemosensitivity studies, we utilized a multiplexed readout for both cell viability and cytotoxicity, allowing us to differentiate between cytostatic and cytotoxic responses.

Results

Our approach revealed that most single-agent anti-cancer compounds that showed activity for the viability readout had no or little cytotoxic effects. Major compound classes that exhibited this type of response included anti-mitotics, mTOR, CDK, and metabolic inhibitors, as well as many agents selectively inhibiting oncogene-activated pathways. However, within the broad viability-acting classes of compounds, there were often subsets of cell lines that responded by cell death, suggesting that these cells are particularly vulnerable to the tested substance. In those cases we could identify differential levels of protein markers associated with cytotoxic responses. For example, PAI-1, MAPK phosphatase and Notch-3 levels associated with cytotoxic responses to mitotic and proteasome inhibitors, suggesting that these might serve as markers of response also in clinical settings. Furthermore, the cytotoxicity readout highlighted selective synergistic and synthetic lethal drug combinations that were missed by the cell viability readouts. For instance, the MEK inhibitor trametinib synergized with PARP inhibitors. Similarly, combination of two non-cytotoxic compounds, the rapamycin analog everolimus and an ATP-competitive mTOR inhibitor dactolisib, showed synthetic lethality in several mTOR-addicted cell lines.

Conclusions

Taken together, by studying the combination of cytotoxic and cytostatic drug responses, we identified a deeper spectrum of cellular responses both to single agents and combinations that may be highly relevant for identifying precision medicine approaches in TNBC as well as in other types of cancers.

Electronic supplementary material

The online version of this article (doi:10.1186/s12943-016-0517-3) contains supplementary material, which is available to authorized users.

Invasion and metastasis markers in cancers

Over 90% of all adults human cancers are of epithelial origin comprising mainly of skin and aero-digestive tract cancers. A significant proportion of our discipline's workload consists of management of these cancers. This review article is to provide clinicians with a summary of the current research findings in invasion and metastasis of epithelial cancers and the translation of some of this information to clinical use particularly related to skin and head and neck cancers (HNSCC). Metastasis is the leading cause of death in cancer patients. Although surgical resection of isolated metastases is beneficial for some patients, the overall efficacy of surgery, chemotherapy or radiotherapy is limited. Clearly, with today's advances in surgery a majority of these primary cancers are resectable and a cure attainable if surgeons could control or inhibit metastasis.

Exploiting the hallmarks of cancer: the future conquest of breast cancer

What separates a malignant from a normal cell? This question has occupied scientists for decades. Although a simple answer remains elusive, several hallmarks of malignancy have been identified. These critical features include uncontrolled proliferation, insensitivity to negative growth regulation, evasion of apoptosis, lack of senescence, invasion and metastasis, angiogenesis and genomic elasticity. Existing therapies predominantly target proliferation either with cytotoxic agents, ionising radiation or more targeted attacks on growth factor signalling pathways. Our most successful therapies to date inhibit proliferation via the oestrogen receptor (ER) and HER2 pathways. Further improvements in therapy must attack the other hallmarks of malignancy and will undoubtedly be accompanied by a better means of individual patient selection for such therapies. Indeed, each of these hallmarks presents a therapeutic opportunity. To believe otherwise would be to assume that a feature is both biologically crucial, yet therapeutically unimportant, an unlikely paradox. Here, we suggest the hallmarks of malignancy as a conceptual framework for understanding novel breast cancer therapies.

A high cytosol value of urokinase-type plasminogen activator (uPA) may be predictive of early relapse in primary breast cancer

BACKGROUND

There is now much data that suggest a relationship between angiogenesis and breast cancer prognosis. Angiogenesis is a multistep process resulting from an ordered set of events and regulated by positive and negative modulators of microvessels growth and by the expression of various proteolytic enzymes.

MATERIALS AND METHODS

We prospectively evaluated VEGF and microvessels density on tumor specimen and cytosolic levels of uPA and PAI-1.

RESULTS

We enrolled 81 primary breast cancer patients. The median follow-up was 38 months. Using the median value as cutoff for the statistical analysis, we found significant correlation between cytosolic levels of uPA and PAI-1 (r = 0.61; p < .0001), between VEGF and steroid hormone receptor status (p = .01), between PAI-1 and tumor grading (p = .009), and between uPA and tumor size greater than 1 cm (p = .04). With respect to the prognosis, we observed a significant correlation between low uPA levels and RFS and an unforeseen, direct correlation between high VEGF values and better RFS.

CONCLUSIONS

Our preliminary results indicate that the cytosolic level of uPA at diagnosis may be predictive of early relapse in primary breast cancer.

Comparison of potential biological markers cathepsin B, cathepsin L, stefin A and stefin B with urokinase and plasminogen activator inhibitor-1 and clinicopathological data of breast carcinoma patients

Cysteine, serine and metalloproteinases and their respective inhibitors are involved in tumor cell invasion and may have prognostic value for the outcome of malignant disease. The aim of the study was to compare the expression of new potential biological tumor markers, the lysosomal cysteine proteinases and their endogenous inhibitors, with that of the serine proteinases and their inhibitors in breast cancinoma and to relate their levels to the clinicopathological factors of the disease. Enzyme-linked immunosorbent assays (ELISAs) were used to measure cysteine cathepsin B (CatB) and cathepsin L (CatL) and their inhibitors, stefin A (StA) and stefin B (StB), together with urokinase (u-PA) and plasminogen activator inhibitor-1 (PAI-1), in 150 cytosols of primary invasive breast carcinoma. A good correlation was found between the levels of the two cysteine proteinases but only a moderate one between those of the cysteine and serine proteinases. u-PA and PAI-1 levels correlated positively with histological grade and negatively with estrogen receptor (ER) status. PAI-1 correlated with most clinicopathological factors that indicate the progression of the disease, while cathepsins and stefins were independent of these factors. In the total group of patients, high u-PA and PAI-1 and low StB levels correlated significantly with shorter disease-free survival (DFS), while CatB, CatL and StA did not. In lymph node negative patients, high CatB and CatL were also associated with shorter DFS, while u-PA remained the most significant of all these biological markers. In conclusion, this retrospective study showed u-PA to be of better prognostic relevance than the cysteine proteinases, though CatB and CatL were relevant for prognosis in lymph node negative breast cancer patients.

Y-box factor YB-1 predicts drug resistance and patient outcome in breast cancer independent of clinically relevant tumor biologic factors HER2, uPA and PAI-1

Intrinsic or acquired resistance to chemotherapy is responsible for failure of current treatment regimens in breast cancer patients. The Y-box protein YB-1 regulates expression of the P-glycoprotein gene mdr1, which plays a major role in the development of a multidrug-resistant tumor phenotype. In human breast cancer, overexpression and nuclear localization of YB-1 is associated with upregulation of P-glycoprotein. In our pilot study, we analyzed the clinical relevance of YB-1 expression in breast cancer (n = 83) after a median follow-up of 61 months and compared it with tumor-biologic factors already used for clinical risk-group discrimination, i.e., HER2, urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor type 1 (PAI-1). High YB-1 expression in tumor tissue and surrounding benign breast epithelial cells was significantly associated with poor patient outcome. In patients who received postoperative chemotherapy, the 5-year relapse rate was 66% in patients with high YB-1 expression. In contrast, in patients with low YB-1 expressions, no relapse has been observed so far. YB-1 expression thus indicates clinical drug resistance in breast cancer. Moreover, YB-1 correlates with breast cancer aggressiveness: in patients not treated with postoperative chemotherapy, those with low YB-1 expression are still free of disease, whereas the 5-year relapse rate in those with high YB-1 was 30%. There was no significant correlation between YB-1 expression and either HER2 expression or uPA and PAI-1 levels. Risk-group assessment achieved by YB-1 differed significantly from that by HER2 or uPA/PAI-1. In conclusion, YB-1 demonstrated prognostic and predictive significance in breast cancer by identifying high-risk patients in both the presence and absence of postoperative chemotherapy, independent of tumor-biologic factors currently available for clinical decision making.

Randomized adjuvant chemotherapy trial in high-risk, lymph node-negative breast cancer patients identified by urokinase-type plasminogen activator and plasminogen activator inhibitor type 1

BACKGROUND

Most patients with lymph node-negative breast cancer are cured by locoregional treatment; however, about 30% relapse. Because traditional histomorphologic and clinical factors fail to identify the high-risk patients who may benefit from adjuvant chemotherapy, other prognostic factors are needed. In a unicenter study, we have found that levels of urokinase-type plasminogen activator (uPA) and plasminogen activator inhibitor type 1 (PAI-1) in the primary tumor are predictive of disease recurrence. Thus, we designed the Chemo N(0) prospective randomized multicenter therapy trial to investigate further whether uPA and PAI-1 are such prognostic factors and whether high-risk patients identified by these factors benefit from adjuvant chemotherapy. After 4.5 years, we present results of the first interim analysis.

METHODS

We studied 556 patients with lymph node-negative breast cancer. The median follow-up was 32 months. All patients with low tumor levels of uPA (< or = 3 ng/mg of protein) and of PAI-1 (< or = 14 ng/mg of protein) were observed. Patients with high tumor levels of uPA (> 3 ng/mg of protein) and/or of PAI-1 (> 14 ng/mg of protein) were randomly assigned to combination chemotherapy or subjected to observation only. All statistical tests were two-sided.

RESULTS

A total of 241 patients had low levels of uPA and PAI-1, and 315 had elevated levels of uPA and/or PAI-1. The estimated 3-year recurrence rate for patients with low tumor levels of uPA and PAI-1 (low-risk group) was 6.7% (95% confidence interval [CI] = 2.5% to 10.8%). This rate for patients with high tumor levels of uPA and/or PAI-1 (high-risk group) was 14.7% (95% CI = 8.5% to 20.9%) (P = 0.006). First interim analysis suggests that high-risk patients in the chemotherapy group benefit, with a 43.8% lower estimated probability of disease recurrence at 3 years than high-risk patients in the observation group (intention-to-treat analysis: relative risk = 0.56; 95% CI = 0.25 to 1.28), but further follow-up is needed for confirmation.

CONCLUSIONS

Using uPA and PAI-1, we have been able to classify about half of the patients with lymph node-negative breast cancer as low risk, for whom adjuvant chemotherapy may be avoided, and half as high risk, who appear to benefit from adjuvant chemotherapy.

Cancer treatment with inhibitors of urokinase-type plasminogen activator and plasmin

The urokinase-type plasminogen activator-plasmin system plays an important role in many normal physiological processes including clot lysis, wound healing, embryogenesis and tissue remodelling. It is also involved in the pathogenesis of human malignancy through its ability to mediate tumour cell growth, invasion and metastatic dissemination. Interfering with this system is an appealing approach for experimental therapy of malignancy for several reasons. This concept is supported by a wealth of preclinical data. Evidence exists suggesting a role for this system in several major human tumour types. Preliminary evidence suggests that agents which block this pathway are effective in therapeutic doses that are already defined and relatively non-toxic. This form of treatment is not likely to carry cross-resistance with other types of cancer therapy and should be applicable to both localised and advanced tumours. Since heterogeneity in responsiveness among various tumour types is expected, clinical effects in given tumours would provide a basis for interpreting mechanisms of tumour progression in vivo and for future development of drugs with improved efficacy. Inhibition of the urokinase-type plasminogen activator-plasmin system remains a promising, but largely untested, area of experimental cancer therapeutics.