Tumor cell–associated tissue factor and circulating hemostatic factors cooperate to increase metastatic potential through natural killer cell–dependent and–independent mechanisms

Tumor cell–associated tissue factor (TF) is a powerful determinant of metastatic potential. TF may increase metastasis by supporting thrombin-mediated proteolysis, through intracellular signaling events mediated by the TF cytoplasmic domain, through TF/fVIIa/fXa–mediated activation of protease-activated receptors, or through a combination of these processes. To better define the relationship between tumor cell-associated TF and circulating hemostatic factors in malignancy, we generated a set of C57Bl/6-derived tumor lines genetically lacking TF, expressing wild-type murine TF, or expressing a mutant TF lacking the cytoplasmic domain. Comparison of the metastatic potential of these cells in immunocompetent mice with genetic deficits in prothrombin, platelet function, or fibrinogen revealed that TF supports metastasis through mechanisms independent of the cytoplasmic domain, but dependent on each of these distal hemostatic factors. TF was neither required for primary tumor growth nor necessary for initial localization of embolized tumor cells within the lungs. Rather, tumor cell fate studies indicated TF supports metastasis by increasing the survival of micrometastases. One mechanism linking TF to metastasis is through a fibrin(ogen)-dependent and platelet-dependent restriction in natural killer cell–mediated clearance of micrometastases. However, TF also supported the early success of micrometastases through an additional mechanism independent of natural killer cells, but coupled to circulating prothrombin.

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Hemostatic Factors Contribute to Tumor Cell Metastatic Potential by a Mechanism Linked to Natural Killer Cell Function.

Blood ◽

10.1182/blood.v104.11.690.690 ◽

2004 ◽

Vol 104 (11) ◽

pp. 690-690 ◽

Cited By ~ 2

Author(s):

Joseph S. Palumbo ◽

Kathryn E. Talmage ◽

Jessica V. Massari ◽

Christine M. La Jeunesse ◽

Matthew J. Flick ◽

...

Keyword(s):

Natural Killer Cell ◽

Tumor Cell ◽

Nk Cells ◽

Natural Killer ◽

Platelet Activation ◽

Cell Function ◽

Nk Cell ◽

Killer Cell ◽

Metastatic Potential ◽

Natural Killer Cell Function

Abstract A linkage between hemostatic system components and tumor cell metastatic potential has been well established, but the underlying mechanism(s) by which various circulating and cell-associated coagulation factors and platelets promote tumor cell dissemination remains to be fully defined. One potential mechanism by which tumor cell-associated microthrombi might enhance metastatic potential is by interfering with the cytolytic elimination of tumor cell emboli by natural killer (NK) cells. In order to explore this hypothesis, we studied tumor dissemination in mice lacking either fibrinogen or Gαq, a G protein critical for platelet activation. Comparative studies of experimental lung metastasis in control and Gαq−/− mice showed that loss of platelet activation resulted in a two-orders-of-magnitude decrease in pulmonary metastatic foci formed by either Lewis lung carcinoma or B16 melanoma. The difference in metastatic success was not the result of differences in tumor growth rate, as tumors transplanted into the dorsal subcutis of Gαq−/− and wildtype animals grew at similar rates. Rather, tumor cell fate analyses using radiolabeled tumor cells showed that the survival of tumor cells within the lung was significantly improved in mice that retained platelet activation function relative to Gαq−/− mice with a profound platelet activation defect. In order to examine the potential interplay between platelet activation and natural killer cell function, we compared pulmonary tumor cell survival in cohorts of control and Gαq−/− mice immuno-depleted of NK cells with an anti-asialo GM1 antibody. Remarkably, platelet function was no longer a determinant of metastatic potential in mice lacking NK cells. Given that fibrin(ogen) is also an established determinant of metastatic success we explored whether the influence of this key hemostatic factor on tumor cell dissemination was also mechanistically-coupled to natural killer cell function. We interbred fibrinogen-deficient mice with Gz-Ly49A transgenic mice known to have a constitutive deficit in NK cells. In those cohorts of mice with normal NK cells, we affirmed the earlier finding that fibrinogen deficiency resulted in a significant diminution in metastatic potential. However, consistent with our findings in mice with defective platelet activation, fibrinogen was found to no longer be a determinant of metastatic potential in mice lacking NK cells. These data establish another important link between innate immune surveillance and the hemostatic system. Further, it appears that at least one mechanism by which tumor cell-associated microthrombi increase metastatic potential is by restricting NK cell-mediated tumor cell elimination. Given that NK cell cytotoxicity requires direct contact with any target cell, one attractive model presently being explored is that tumor cell-associated platelets physically block NK cell access to tumor cell emboli.

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Platelets and fibrin(ogen) increase metastatic potential by impeding natural killer cell–mediated elimination of tumor cells

Blood ◽

10.1182/blood-2004-06-2272 ◽

2005 ◽

Vol 105 (1) ◽

pp. 178-185 ◽

Cited By ~ 529

Author(s):

Joseph S. Palumbo ◽

Kathryn E. Talmage ◽

Jessica V. Massari ◽

Christine M. La Jeunesse ◽

Matthew J. Flick ◽

...

Keyword(s):

Natural Killer Cell ◽

Natural Killer ◽

Tumor Cells ◽

Platelet Activation ◽

Cell Function ◽

Killer Cell ◽

Metastatic Potential ◽

Pulmonary Vasculature ◽

Tumor Dissemination ◽

Hemostatic Factors

Abstract To test the hypothesis that platelet activation contributes to tumor dissemination, we studied metastasis in mice lacking Gαq, a G protein critical for platelet activation. Loss of platelet activation resulted in a profound diminution in both experimental and spontaneous metastases. Analyses of the distribution of radiolabeled tumor cells demonstrated that platelet function, like fibrinogen, significantly improved the survival of circulating tumor cells in the pulmonary vasculature. More detailed studies showed that the increase in metastatic success conferred by either platelets or fibrinogen was linked to natural killer cell function. Specifically, the pronounced reduction in tumor cell survival observed in fibrinogen- and Gαq-deficient mice relative to control animals was eliminated by the immunologic or genetic depletion of natural killer cells. These studies establish an important link between hemostatic factors and innate immunity and indicate that one mechanism by which the platelet-fibrin(ogen) axis contributes to metastatic potential is by impeding natural killer cell elimination of tumor cells.

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Tumor Cell-Associated Tissue Factor Supports Metastatic Potential through Both NK Cell-Dependent and -Independent Mechanisms.

Blood ◽

10.1182/blood.v108.11.66.66 ◽

2006 ◽

Vol 108 (11) ◽

pp. 66-66 ◽

Cited By ~ 1

Author(s):

Joseph Palumbo ◽

Kelley A. Barney ◽

Matthew J. Flick ◽

Kathryn E. Talmage ◽

Keith W. Kombrinck ◽

...

Keyword(s):

Tumor Cell ◽

Nk Cells ◽

Natural Killer ◽

Tissue Factor ◽

Tumor Cells ◽

Cell Function ◽

Nk Cell ◽

Metastatic Potential ◽

Hemostatic System ◽

Hemostatic Factors

Abstract Multiple lines of evidence indicate that the hemostatic system contributes to cancer dissemination. Previous studies have shown that tumor cell-associated tissue factor (TF) expression is a crucial determinant of metastatic potential. Furthermore, we have shown that tumor cell-associated TF supports metastatic potential through mechanism(s) dependent on multiple circulating hemostatic system components, including prothrombin, platelets, fibrinogen and, more recently, fXIII. At least two of these circulating hemostatic factors (platelets and fibrinogen) have been shown to support metastatic potential by impeding the clearance of recently embolized tumor cells by natural killer (NK) cells. It is reasonable to hypothesize that tumor cell-associated TF expression also supports metastatic potential by a mechanism coupled to NK cell function. Here, we used C57BL/6-derived, Ras-transformed tumor cell lines expressing wildtype murine tissue factor (TFWT), a mutant TF lacking the intracytoplasmic portion (TFΔTail), or no tissue factor (TFO) to directly examine the interplay between tumor cell-associated TF and NK cell function in determining metastatic potential. Each of these cell lines was capable of robust, comparable tumor growth in wildtype C57BL/6 mice. Loss of either platelet function or fibrinogen significantly diminished the metastatic potential of TFWT cells, but this effect was entirely abrogated by the concomitant loss of NK cells. Similar results were obtained with TFΔTail cells, indicating that the cytoplasmic portion of TF is not critical to these interactions. To determine if the increase in metastatic potential conferred by tumor cell-associated TF expression is entirely linked to NK cell function, we compared the metastatic potential and early survival of TFWT and TFO cells in mice with and without NK cells. TFOcells rarely formed any visible metastatic foci in mice with intact NK cell function, while TFWT cells were aggressively metastatic. Importantly, TF expression remained a significant determinant of metastatic potential even in mice lacking NK cells. Comparisons of the early fate of TFWT and TFO cells revealed that TF expression was not a determinant of initial tumor cell localization within the lungs. Rather, TF expression supported the sustained adherence and/or survival of tumor cells. Taken together, these data indicate that one mechanism linking tumor cell-associated TF expression to metastatic potential is coupled to circulating hemostatic factors and results in impaired NK cell-mediated clearance of recently established micrometastatic foci. However, TF expression also supports metastasis by at least one additional mechanism that is independent of natural killer cell function.

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Natural Killer Cell Inspired AIE Nanoterminator for Blood-Brain-Barrier Crossing via Tight-Junction Modulation and NIR-II Gliomas Theranostics

10.26434/chemrxiv.12504404.v1 ◽

2020 ◽

Author(s):

Guanjun Deng ◽

Xinghua Peng ◽

Zhihong Sun ◽

Wei Zheng ◽

Jia Yu ◽

...

Keyword(s):

Natural Killer Cell ◽

Natural Killer ◽

Intracellular Signaling ◽

Soft Matter ◽

Tumor Imaging ◽

Nk Cell ◽

Killer Cell ◽

Light Illumination ◽

Blood Brain ◽

Intracellular Signaling Cascade

Nature has always inspired robotic designs and concepts. It is conceivable that biomimic nanorobots will soon play a prominent role in medicine. In this paper, we developed a natural killer cell-mimic AIE nanoterminator (NK@AIEdots) by coating natural kill cell membrane on the AIE-active polymeric endoskeleton, PBPTV, a highly bright NIR-II AIE-active conjugated polymer. Owning to the AIE and soft-matter characteristics of PBPTV, as-prepared nanoterminator maintained the superior NIR-II brightness (quantum yield ~8%) and good biocompatibility. Besides, they could serve as tight junctions (TJs) modulator to trigger an intracellular signaling cascade, causing TJs disruption and actin cytoskeleton reorganization to form intercellular “green channel” to help themselves crossing Blood-Brain Barriers (BBB) silently. Furthermore, they could initiatively accumulate to glioblastoma cells in the complex brain matrix for high-contrast and through-skull tumor imaging. The tumor growth was also greatly inhibited by these nanoterminator under the NIR light illumination. As far as we known, The QY of PBPTV is the highest among the existing NIR-II luminescent conjugated polymers. Besides, the NK-cell biomimetic nanorobots will open new avenue for BBB-crossing delivery.

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