297 research outputs found
A risk-averse strategy for blackjack using fractional dynamic programming
We present how blackjack is related to a discrete-time control problem, rather than a zero-sum game. Using the compiler Visual C++, we write a program for a strategy for blackjack, but instead of maximizing the expected value, we use a risk-averse approach. We briefly describe how this risk-averse strategy is solved by using a special type of dynamic programming called fractional dynamic programming
The Potential Role of MT and Vimentin Immunoreactivity in the Remodeling of the Microenvironment of Parotid Adenocarcinoma
A tumor stimulates the remodeling of its microenvironment in order to control and accelerate its own growth and to initiate metastases. To create metastases the tumor cells must first acquire the ability to detach from the main tumor and to adhere to, invade, and degrade the adjacent extracellular matrix. The cells must then be able to enter the lumen of the vessels where they home the distant tissues and organs by forming secondary tumors. The acquisition of this phenotype is related to the phenomenon of epithelial-to-mesenchymal transition. On the molecular level, this process is typified by a change in the expression of epithelial markers and by the enhancement of the expression of mesenchymal markers like vimentin that are responsible for cell migration and invasion. Metallothioneins have been shown to help protect against apoptosis. The expression of MT by tumor cells plays an important and complex role not only because of its pro-proliferative, anti-apoptotic activity, but also because it inhibits the immune response. The aim of the present study was to evaluate the immunoreactivity of vimentin and MT in the salivary gland adenocarcinoma and its stroma in order to observe the phenomenon of stromal remodeling. The tissue samples of salivary gland adenocarcinomas and their stromas and the palatine tonsils which constituted the reference group were obtained during routine surgical procedures. The immunoreactivity of vimentin, metalothionein, CD56, CD57 antigens was evaluated by the immunohistochemistry method in 30 tissue samples of parotid adenocarcinoma. The patient’s consent was obtained in each case. A statistically significantly higher level of MT immunoreactivity was observed in the adenocarcinoma tissue slides than in either the stromal slides or the reference slides while no differences in MT immunoreactivity were detected when the stroma and reference tissue slides were compared. A statistically significantly higher vimentin immunoreactivity level was identified in the tumor microenvironment tissue slides than in the tumor tissue slides, and a statistically significantly higher level of vimentin immunoreactivity was identified in the tumor microenvironment slides than in the slides of the reference tissue, while no differences were identified between the adenocarcinoma tissue slides and the reference slides with respect to vimentin immunoreactivity. A statistically significantly higher number of CD56- and CD57-expressing cells were identified in the reference tissue slides than in either the adenocarcinoma or stromal slides. In conclusion, the stroma of salivary gland adenocarcinoma in this study has been characterized by remodeling. The remodeling is represented by the expression of both vimentin and MT and by a deficit of CD57- and CD58-expressing cell infiltration. This situation would seem to be the result of immune tolerance for the tumor developing within the tumor microenvironment. Furthermore, the presence of MT and vimentin immunoreactivity in the fibroblasts of the tumor stroma may constitute a marker of active tissue remodeling
High tumor cell vimentin expression indicates prolonged survival in patients with ovarian malignant tumors
The analysis of the level of Treg lymphocytes in the blood of patients with endometrial cancer before and after the surgery — preliminary study
Introduction. The progression of cancer is a complex process involving host-tumour interactions taking place in cancer and in the cancer microenvironment. The tumour remodels the microenvironment into the suppressive profile by various mechanisms. One of the most important elements of this mechanism is the inducing of the infiltration of Treg lymphocytes into cancer and its microenvironment. The aim of the present study was to evaluate the alterations of the Treg cell population in the peripheral blood of patients before and after the surgical treatment for endometrial cancer.
Material and methods. For the present study 24 patients with endometrial cancer were recruited. All the patients were treated surgically. The peripheral blood samples were collected from the endometrial cancer patients before operation and three days after the surgical procedure and evaluated using flow cytometry method.
Results. CD25+ CD4+ FOXP3+ T cells were found in all the examined peripheral blood samples derived from the endometrial cancer patients in the days before and following applied surgery. We observed differences before and after the applied surgical procedure in patients treated for uterine cancer. The highest number of Treg cells in the peripheral blood was demonstrated before the surgical procedure; it diminished statistically significantly following the surgery.
Conclusions. The decrease of the percentage of Treg cells in blood sera in patients following radical surgical treatment might be useful in measuring the radicalism of the treatment. The monitoring of the level of selective immune system suppression related to Treg cell blood serum levels during cancer therapy might support a decision to supplement the standard therapy with immunotherapy or to increase the degree of radicalism of the applied therapy.
High tumor cell vimentin expression indicates prolonged survival in patients with ovarian malignant tumors
Objectives: The main aims of the study were to investigate the expression of vimentin and its correlation with the overall survival (OS) of patients with malignant ovarian tumors, and the correlation between vimentin expression and tumor stroma characteristics. Material and methods: The study focused on 94 malignant ovarian tumors that had been collected from women who were treated in the Department of Gynecology and Oncology of the Lukaszczyk Oncological Center, Bydgoszcz, Poland. Vimentin expression was assessed in both the cancer cells (expression intensity and quantitative analysis) and the tumor stroma (expression intensity). Vimentin expression was analyzed according to both stromal cellularity and the clinicopatho- logical features of the disease. Results: Both high cancer cell vimentin expression intensity and high quantitative vimentin expression (up to and includ- ing 30% of cells) indicated a significantly prolonged OS. Low vimentin stromal expression was associated with prolonged OS, although the difference did not reach the level of significance. High tumor cell vimentin expression intensity was as- sociated with significantly higher vimentin stromal expression. High vimentin expression in the tumor stroma indicated a significantly higher cellularity of the tumor stroma. Vimentin expression in cancer cells and the tumor stroma were not dependent on the histopathological type, the tumor grade or the FIGO stageof the disease. Conclusions: High cancer cell vimentin expression is associated with an improved OS of patients with malignant ovar- ian tumors. The expression of vimentin in ovarian malignancies may influence the structure of the tumor stroma
The potential predictive value of serum sRCAS1 levels for overall survival in endometrial cancer
Objectives: The main aim of the study was to evaluate the impact of levels of serum soluble receptor-binding cancer antigen expressed on SiSo cells (sRCAS1) on the overall survival (OS) rates in patients with endometrial cancer. Furthermore, we analyzed sRCAS1 levels according to the clinicopathological characteristics of the disease. Material and methods: The study group comprised 43 patients who were being treated for endometrial cancer. We included 10 low-risk, 20 intermediate-risk and 13 high-risk endometrial cancers using the criteria of the European Society for Medical Oncology (ESMO), the European Society for Radiotherapy & Oncology (ESTRO) and the European Society of Gynaecological Oncology (ESGO). Serum sRCAS1 levels were obtained before and after surgery. Serum sRCAS1 levels were assessed using the ELISA method. Results: In our univariate analysis, both the pre- and post-surgery high sRCAS1 groups of patients with endometrial cancer indicated a shortened OS. However, in our multivariate analysis, when patients’ age and disease-related risk was taken into consideration, only the post-surgery sRCAS1 levels remained as independent prognostic factors of a poor OS. Pre-treatment serum sRCAS1 levels were statistically significantly higher than post-surgery sRCAS1 levels; however, the difference between pre- and post-surgery sRCAS1 levels did not influence the patients’ OS rate. Pre- and post-surgery sRCAS1 levels did not differ according to tumor grade, stage of the disease or the disease-related risk group. Conclusions: High post-surgery serum sRCAS1 levels seem to be an independent indicator of shortened overall survival in patients with endometrial cancer.
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