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Copyright of Canadian Journal of Dental Hygiene is the property of Canadian Dental Hygienists Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Simple Summary: Blood clots are formed when blood vessels are injured. They help stop bleeding and heal wounds, but can also cause serious problems if they block blood flow or break off and travel to other organs. This study investigates how blood clots differ in people with cancer compared to healthy or non-cancerous individuals. This study found that cancer patients have higher levels of histones in their blood, which make their clots stiffer and resistant to lysis. Further, clots formed in cancer patients have higher viscoelastic properties, and hence are harder to break down. These findings suggest that cancer patients have abnormal clotting properties that may increase their risk of developing thrombosis, and evaluating these properties can be helpful in detecting cancer. Background: Blood viscoelasticity and plasma protein levels can play an important role in the diagnosis and prognosis of cancer. However, the role of histones and DNA in modulating blood clot properties remains to be investigated. This study investigates the differences in blood viscoelasticity and plasma protein levels among cancer patients, individuals with other diseases, and healthy individuals. Methods: Blood samples were collected from 101 participants, including 45 cancer patients, 22 healthy individuals, and 34 individuals with other diseases. Rheological properties of clots formed in vitro by reconstituted elements of fibrinogen or plasma were analyzed with an Anton Paar Rheometer, USA. Plasma protein levels of D-dimer, TPA, EPCR, fibrinogen, and histone H3 were measured through ELISA. Blood clots were formed with or without DNA and histones (H3) by adding thrombin and calcium to plasma samples, and were evaluated for viscoelasticity, permeability, and degradation. Results: Cancer patients show higher blood viscoelasticity and plasma D-dimer levels compared to healthy individuals and individuals with other diseases. Our in vitro analysis showed that the addition of histone to the plasma results in a significant decrease in viscoelasticity and mean fiber thickness of the clot formed thereafter. In parallel studies, using plasma from patients, DNA and histones were detected in fibrin clots and were associated with less degradation by t-PA. Moreover, our results show that the presence of DNA and histones not only increases clots' permeability, but also makes them more prone to degradation. Conclusions: Plasma histones and DNA affect the structure of the clot formed and induce defective fibrinolysis. Moreover, the increased viscoelastic properties of plasma from cancer patients can be used as potential biomarkers in cancer prognosis. [ABSTRACT FROM AUTHOR]

Tumor Biology, owned by the International Society of Oncology and BioMarkers and currently published by IOS Press, lost its Clarivate impact factor of 3.650 in 2017. It has been plagued by over 100 retractions due to paper mills (including a batch of 15 papers published between 2014 and 2016 that were retracted at the end of 2021), faked peer reviews, and forged research. According to PubMed, the number of papers published by Tumor Biology has been reduced to a mere trickle, dropping from 707 in 2017 to 66 in 2018. It is unclear how Tumor Biology will be able to recover from such disastrous reputational damage and whether there is even merit in continuing its publication. Other journals for cancer and oncology research would do well to observe this case closely and learn from its mistakes. [ABSTRACT FROM AUTHOR]

In vitro models for screening new cancer chemotherapeutics often rely on two-dimensional cultures to predict therapeutic potential. Unfortunately, the predictive power of these models is limited, as they fail to recapitulate the complex three-dimensional environments in tumors that promote a chemoresistant phenotype. In this study, we describe the preparation and characterization of paper-based cultures (PBCs) engineered to assess chemotherapeutic effectiveness in three dimensional, diffusion-limited environments. Similar environments are found in poorly vascularized tumors. Monotonic gradients develop across these cultures, which are assembled by stacking cell-laden paper scaffolds to yield thick tissue-like structures, and provide distinct chemical environments for each scaffold. After prolonged incubation, the scaffolds can simply be peeled apart and analyzed. Through fluorescence imaging, we determined that viable and proliferative cell populations were most abundant in scaffolds close to the nutrient-rich medium. By adjusting the cell density, we modulated the spatiotemporal evolution of oxygen gradients across the cultures and correlated these environmental changes with cellular sensitivity to SN-38 exposure. From these results, we showed that differences in the oxygen gradients produced cellular populations with significantly different chemosensitivities. Through this work, we highlight PBCs ability to serve as an analytical model capable of determining chemotherapeutic effectiveness under a range of chemical environments. [ABSTRACT FROM AUTHOR]