Direct Oral Anticoagulants in Cancer Patients. Time for a Change in Paradigm

Thrombosis is a more common occurrence in cancer patients compared to the general population and is one of the main causes of death in these patients. Low molecular weight heparin (LMWH) has been the recognized standard treatment for more than a decade, both in cancer-related thrombosis and in its prevention. Direct oral anticoagulants (DOACs) are a new option for anticoagulation therapy. Recently published results of large randomized clinical trials have confirmed that DOAC may be a reasonable alternative to LMWH in cancer patients. The following review summarizes the current evidence on the safety and efficacy of DOAC in the treatment and prevention of cancer-related thrombosis. It also draws attention to the limitations of this group of drugs, knowledge of which will facilitate the selection of optimal therapy.

Co-localization of Coagulation Factor X and its Inhibitory System, PZ/ZPI, in Human Endometrial Cancer Tissue

BACKGROUND/AIM

Hemostatic system components contribute to cancer progression independently from their roles in hemostasis. It has been shown that protein Z (PZ)/protein Z-dependent protease inhibitor (ZPI) inhibit coagulation factor X (FX). The aim of the study was to analyze the expression of PZ/ZPI in relation to the main coagulation factor - FX in human endometrial cancer tissue.

MATERIALS AND METHODS

Immunohistochemical analysis was performed on 21 endometrial cancer specimens employing antibodies against ZPI, PZ and FX.

RESULTS

Endometrial cancer cells showed a strong expression of ZPI and PZ and medium expression of FX. Normal endometrial tissue showed no expression of ZPI, PZ or FX.

CONCLUSION

Strong expression of PZ and ZPI in endometrial cancer cells suggests a role of these proteins in endometrial cancer.

Protein Z/protein Z-dependent protease inhibitor system in loco in human gastric cancer

In gastric cancer, hemostatic system components contribute to cancer progression, as activation of factor X (FX) was observed. The protein Z (PZ)/protein Z-dependent protease inhibitor (ZPI) complex inhibits factor Xa proteolytic activity. The purpose of this study was to determine the distribution of ZPI and PZ in relation to FX, and prothrombin fragment (F1 + 2), a standard marker for blood coagulation activation, in human gastric cancer tissue. ABC procedures and a double staining method employed polyclonal antibodies against PZ, FX, and F1 + 2 and a monoclonal antibody against ZPI. In situ hybridization (ISH) methods employed biotin-labeled 25-nucleotide single-stranded DNA probes directed to either PZ or ZPI mRNAs. FX and components of PZ/ZPI coagulation inhibitory system were observed in cancer cells. F1 + 2 was observed in gastric cancer cells as well. Double staining studies revealed FX/PZ, FX/ZPI, and PZ/ZPI co-localization on gastric cancer cells. ISH studies demonstrated the presence of PZ mRNA and ZPI mRNA in gastric cancer cells indicating induced synthesis of these proteins. The co-localization of PZ/ZPI and FX in gastric cancer cells indicates in loco that these proteins may play a role in anticoagulant events at the tumor tissue.

Co-localization of Protein Z, Protein Z-Dependent protease inhibitor and coagulation factor X in human colon cancer tissue: implications for coagulation regulation on tumor cells

INTRODUCTION

Several hemostatic system components, including factor X (FX), contribute to cancer progression. The Protein Z (PZ)/protein Z-dependent protease inhibitor (ZPI) complex directly inhibits factor Xa proteolytic activity. The aim of this study was to determine the antigenic distribution of ZPI and PZ, in relation to FX, as well as indicators of blood coagulation activation (F1+2 and fibrin) in human colon cancer tissue.

MATERIALS & METHODS

Studies were performed on human colon cancer fragments. Immunohistochemical (IHC) ABC procedures and double staining method employed polyclonal antibodies against PZ, FX, F1+2 and monoclonal antibodies against ZPI and fibrin. In-situ hybridization (ISH) methods employed biotin-labeled 25-nucleotide single-stranded DNA probes directed to either FX, PZ or ZPI mRNAs.

RESULTS

Expression of FX, PZ and ZPI in association with colon cancer cells was observed by IHC. Moreover, the presence of both F1+2 and fibrin in association with colon cancer cells was found, which indicates that blood coagulation activation proceeds extravascularly at the tumor site. Furthermore, expression of FX and PZ was visualized in association with endothelial cells. In turn, colon cancer-associated macrophages were characterized by FX , PZ and ZPI presence. The double staining studies revealed strong FX/PZ, FX/ZPI, as well as PZ/ZPI co-localization on colon cancer cells. ISH studies revealed the presence of FX mRNA, PZ mRNA and ZPI mRNA in colon cancer cells indicating induced synthesis of these proteins.

CONCLUSIONS

The localization of PZ/ZPI and FX in colon cancer cells indicates that PZ/ZPI may contribute to anticoagulant events at the tumor site. Strong co-localization of PZ/ZPI and FX in cancer cells, and the presence of the mRNAs encoding the proteins, suggests their role in the tumor's biology. However, the presence of F1+2 and fibrin at the colon cancer site also suggests that the regulation of FXa by the PZ/ZPI complex at this site is incomplete.

Protein Z/protein Z-dependent protease inhibitor system in human non-small-cell lung cancer tissue

INTRODUCTION

NSCLC progression is often associated with VTE. Activation of factor X is an important step in blood coagulation activation in cancer patients. PZ)/ZPI contribute to direct factor Xa inhibition, and ZPI - attenuates factors IXa and XIa activity. The role of the PZ/ZPI in NSCLC is obscure. The aim of the study was to localize ZPI and PZ in NSCLC tissue in relation to factors X, IX and XI, as well as indicators of blood coagulation activation: prothrombin fragment F1+2 (F1+2) and fibrin.

MATERIAL & METHODS

Immunohistochemical studies were performed on surgical NSCLC specimens employing antibodies against ZPI, PZ, coagulation factors X, IX, XI, as well as fibrinogen, F1+2 and fibrin. A semiquantitative analysis (acc. to immunoreactive score-IRS) was conducted.

RESULTS

Medium expression of ZPI(IRS=6.5), together with weak expression of PZ(IRS=4), was observed in cancer cells. Strong or medium staining for factors IX, X, and XI(IRS=8-9) was revealed in cancer cells. Fibrinogen(IRS=10) and fibrin(IRS=8) were demonstrated in tumor stroma and cancer cells. F1+2(IRS=10) was localized in NSCLC cells. Endothelial cells (ECs) and tumor infiltrating macrophages (TAMs) were characterized by a positive staining for ZPI and PZ.

CONCLUSIONS

ZPI and PZ expression in NSCLC cells, ECs and TAMs may suggest a role for PZ/ZPI in the anticoagulant mechanisms at the tumor site. The presence of F1+2 and fibrin, along with a disproportional expression of ZPI and PZ, might point to impaired function of the coagulation inhibitory system in NSCLC tissue.

Activity of trastuzumab-based therapy beyond disease progression in heavily pretreated metastatic breast cancer patients—Single institution experience

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Background: Benefits from continuing trastuzumab-based (TZB) therapy beyond disease progression in HER-2-overexpressing metastatic breast cancer (MBC) patients (pts) remain obscure. Methods: A retrospective analysis was undertaken to assess activity of TZB therapy for MBC pts treated in our institution from 2002 to 2005 outside clinical trials. Results: 27 pts were evaluated. Median age: 52 years (range, 33–62). 9 pts (33.3%) were premenopausal. Hormonal receptors status: 9 pts ER(+), 4 pts PgR (+), 2 unknown. HER-2 overexpression was determined by IHC staining (3+ score) in all pts. Metastases location: 18 pts soft tissues/bone, 18 pts visceral disease. Median number of metastatic sites: 2 (range: 1–4). 9 pts (33.3%) had metastases in < 2 locations. 16 pts (59.2%) received neo/adjuvant chemotherapy: 11 pts doxorubicin, 8 pts CMF, 2 pts docetaxel, 4 pts other. Median previous chemotherapy lines for advanced disease: 2 (range: 0–6). 16 pts received doxorubicin/epirubicin, 14 pts docetaxel, 13 pts vinorelbine as a part of advanced disease chemotherapy regimen. Trastuzumab was administered at standard doses and combined with docetaxel, vinorelbine, cisplatin, capecitabine, etoposide, gemcitabine or administered as monotherapy. Response for the first-line TZB therapy was as follows: CR 5/27 pts (18.5%); PR 10/27 pts (37%). Median TTP was 5.8 months (range: 0–22). 14/27 pts (51.8%) received a second-line TZB therapy beyond disease progression. Response for the second-line therapy: CR 2/14 pts (14.3%); PR 5/14 pts (35.7%). Median TTP was 5.1 months (range: 0–24). 6/14 pts received a third-line and subsequent lines (up to five lines) of TZB therapy. PR for subsequent lines of therapy was observed in 4 pts. Median survival has not been reached. Pts who received ≥2 of TZB regimens survived significantly longer than pts who had received only 1 regimen (P = 0,02 logrank). Pts with metastasis in 1 location survived significantly longer than pts with metastasis in ≥2 sites (P = 0,01 logrank). Conclusions: Trastuzumab-based therapy seems to be active in MBC pts beyond disease progression even in heavily pretreated population. Durable responses were observed in some cases.

No significant financial relationships to disclose.

[Expression evaluation of in loco coagulation system in colorectal cancer]

Colorectal cancer is the third most often cause of morbidity and mortality due to cancer in Poland. Thromboembolic complications are common events during the course of the disease. It is well known that hemostatic proteins play an important role in cancer progression. The purpose of the study was to evaluate the in loco interactions among colorecatal cancer and coagulation factors. 21 cases of G2 colorectal adenocarcinoma obtained during surgical resection were examined. Immunohistochemical procedures according to ABC method were employed. Tissue factor (TF) and coagulation factors II, VII, X, IX were observed in cancer cells and except factors II and IX--in tumor associated macrophages. TF was also demonstrated in endothelial cells of small blood vessels. Strong expression of fibrinogen was observed among connective tissue at some distance around malignant tumor while weaker expression was found in tumor stroma. Expression of F(1+2), the by-product of thrombin generation, was revealed in cancer cells, macrophages and in the tumor stroma. The results indicate extravascular activation of blood coagulation in loco in colorectal cancer that is TF-dependent.

[Protein Z]

Protein Z (PZ) is a 6.2 kDa vitamin K-dependent protein, synthesized in the liver. The gene for human PZ is localized to chromosome 13 at band 34 q. The structure of PZ is very similar to that of factors VII, IX, X and protein C. Very low plasma levels of protein Z were observed under oral anticoagulant treatment. The cause of this phenomenon might be increased protein Z binding on the surface of endothelial cells. Protein Z is consumed during coagulopathy. About 60% of humans suffering from a bleeding tendency of unknown origin presented with decreased plasma levels of protein Z. PZ forms a Ca(2+)-dependent complex with activated factor X (Xa) on phospholipid surfaces, that leads to the inhibition of factor Xa and decrease in thrombin generation. Inhibition of factor Xa may be caused directly by protein Z or indirectly by the activity of protein Z-dependent protease inhibitor (ZPI). ZPI is a 72 kDa member of the serpin family of proteinase inhibitors, synthesized in the liver. ZPI circulates in plasma in complex with protein Z. ZPI in the presence of Ca2+ and phospholipids inhibits factor Xa. The presence of protein Z enhances this process by more than 1000 times. ZPI also inhibits activated factor XI in the absence of protein Z, Ca2+ or phospholipids. Protein Z deficiency may induce bleeding as well as prothrombotic tendencies and might occur as an inherited disorder. Protein Z deficiency may aggravate mild bleeding tendency in subjects with diagnosed borderline decrease in von Willebrand factor and factor VII activity. Patients presenting with factor V Leiden mutation and low protein Z levels show earlier onset and higher frequency of thromboembolic events comparing to patients with normal protein Z levels.

[The location of components of fibrinolytic system in laryngeal cancer]

Laryngeal cancer is the most common neoplasm of the head and neck region. Laryngeal cancer patients experience thromboembolic complications more often than the general population. Our previous studies revealed in loco activation of blood coagulation in laryngeal cancer. The purpose of the present study was to examine the interactions among the laryngeal cancer cells and fibrinolytic system components in loco. Twenty-two cases of squamous carcinoma of the larynx were examined. AMeX method-preserved cancer tissues were examined using immunohistochemical ABC method. Fibrin and D-D fibrin dimers were demonstrated in the matrix, predominantly on the tumor-host front. Plasminogen, tissue-type plasminogen activator (t-PA) and plasmin were detected in cancer cells, but the intensity of their expression revealed a negative correlation with the degree of malignancy. A weak expression of high molecular weight urokinase (HMW-UK) was observed in cancer cells in the centers of the cancer foci, and a product of its degradation--low molecular weight urokinase (LMW-UK) was observed in cancer cells on the invasion front. The presence of plasminogen activator inhibitors (PAI-1, PAI-2, PAI-3) was also documented in the cancer cells. The expression of urokinase receptor (u-PAR) was very weak. Based on the results of the study, we suggest that in laryngeal cancer a suboptimal activation of fibrinolysis occurs that contributes to fibrin deposition in the tumour.

Concentration of interleukin-6 (IL-6), interleukin-8 (IL-8) and interleukin-10 (IL-10) in blood serum of breast cancer patients

PURPOSE

Interleukins may stimulate cancer cells growth and contribute to locoregional relapse as well as metastasis. Permanent synthesis and release of these cytokines leads to augmentation of their serum concentration that might be utilized as a marker of immunity status and immune system activation in prognosis and monitoring of the course of cancer.

MATERIAL AND METHODS

Therefore, in the present study we assessed the concentration of IL-6, IL-8 and IL-10 in blood serum of breast cancer patients to determine whether it correlates with the disease progression.

RESULTS

We showed statistically higher serum concentrations of IL-6, IL-8 and IL-10 in breast cancer patients in comparison with healthy women, which also correlated with clinical stage of breast cancer.

CONCLUSIONS

The present study indicates that elevated IL-6, IL-8, and IL-10 serum concentration, are strongly associated with breast cancer and correlate with clinical stage of disease. It was feasible that it can be used to diagnose women with breast cancer and to identify patients with a poor prognosis who may benefit from more aggressive management.