Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

The assessment of T-cell subsets in response to treatment in patients with breast or oesophageal cancer

Dissertation (MSc)--University of Pretoria, 2014.

Saved in:
Bibliographic Details
Other Authors: Mokoena, Thabo Mishack
Format: Thesis
Language:English
Published: University of Pretoria 2015
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867613655133061120
access_status_str Open Access
author2 Mokoena, Thabo Mishack
author_browse Mokoena, Thabo Mishack
author_facet Mokoena, Thabo Mishack
collection Thesis
dc_rights_str_mv © 2015 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.
description Dissertation (MSc)--University of Pretoria, 2014.
format Thesis
id oai:repository.up.ac.za:2263/45940
institution University of Pretoria (South Africa)
language English
last_indexed 2026-06-10T12:39:35.842Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository
publishDate 2015
publishDateRange 2015
publishDateSort 2015
publisher University of Pretoria
publisherStr University of Pretoria
record_format dspace
source_str UPSpace — University of Pretoria Institutional Repository
spelling oai:repository.up.ac.za:2263/45940 The assessment of T-cell subsets in response to treatment in patients with breast or oesophageal cancer Mokoena, Thabo Mishack Cockeran, Riana Moodley, Vanessa Wedi, Opope Oyaka UCTD Cancer Immune system Breast cancer Treatment Dissertation (MSc)--University of Pretoria, 2014. Background: Cancer is a crippling disease affecting 32.6 million people globally. It is currently ranked as the leading cause of death worldwide, and is associated with significant morbidity and mortality. Despite advances made in the prevention, detection and treatment of malignancy, there remains a dearth of accurate and feasible prognostic and predictive factors for use in the management of patients suffering from cancer in developing countries. It is widely recognized that the immune system plays a fundamental role in regulating the development and progression of malignancy. T-lymphocytes in particular have been categorized into T-cell populations which either promote (T regulatory cells) or prevent (CD4+ and CD8+ T-lymphocyte) cancer development and progression. Aim: The aim of this thesis was to evaluate whether the levels of the respective pro- (T regulatory) and anti- (CD4+ and CD8+ T-lymphocytes) cancer T-lymphocyte subsets before treatment, and alterations of these levels following conventional anticancer treatment (surgery, chemotherapy and radiotherapy) could be used as markers of prognosis in conjunction with other well known prognostic factors, or as predictors of short term (5-7 weeks post-treatment) survival. Methods: Blood samples were collected from 25 breast cancer, and 10 oesophageal cancer patients before antitumor treatment, at day 1 post-treatment and at 5-7 weeks post-treatment. The circulating concentrations and percentages of CD4+, CD8+ and T regulatory cells were determined from whole blood by flow cytometry. These levels were used to determine the CD4: CD8+ T-cell ratio, the CD4+ Treg: total CD4+ Treg ratio and the CD8+ Treg: total CD8+ Treg ratio. Results: Early (stage 1 and 2) HER-2/neu negative breast cancer was associated with a higher CD4+ (558 versus 133 cells/μl; P=0.05) and CD8+ T-cell count (198 versus 58 cells/μl; P=0.05) as compared to early HER-2/neu positive breast cancer. Breast cancer patients showed a significant decline in CD8+CD25+CD127+ Treg cell subsets (P=0.012) following antitumor treatment. However, oesophageal cancer patients showed an increasing trend in CD8+CD127+FoxP3+ Treg cells at day 1 post-treatment (P=0.045) and at 5-7 weeks posttreatment (P=0.044). Patients who demised displayed a significantly lower CD4+: CD8+ Tcell ratio (1.2 versus 2.2; P=0.044) before treatment, as well as a lower CD4+ (111 versus 390 cells/μl; P=0.0046) and CD8+ T-cell count (88 versus 160 cells/μl; P=0.058) at day 1 posttreatment, as compared to those who survived. While patients who survived displayed a higher CD8+ Treg: total CD8+ T-cell ratio (1.48 versus 0.53 P=0.0126) before treatment, and a higher CD4+CD25+CD127+ Treg cell level at day 1 post-treatment (9 versus 2 cells/μl; P=0.047), as compared to those who demised. Conclusion Taken together the findings of this thesis suggest that the CD4+ and CD8+ T-cell count and CD4:CD8 T-cell ratio may serve as predictors of short-term survival in the management of breast and oesophageal cancer. Furthermore, HER-2/neu receptor status may reflect the underlying immune status and antitumor effector activity of a patient. These findings also suggest that T regulatory cell subsets are a heterogeneous group of cells with variable frequencies at presentation and in responses to antitumor treatment depending on the cancer type, stage of disease and antitumor treatment employed. This further illustrates the need for more work aimed at better characterizing the different Treg cell subsets to better identify which subsets are associated with patient prognosis. In summary, this work presents evidence to suggest a role for the T-cell immune profile as a prognostic and predictive parameter in the management of cancer. It argues for early assessments of cancer patients’ immune status as part of the diagnostic work up and that the immune status is taken into consideration when decisions are made regarding treatment. tm2015 Immunology MSc Unrestricted 2015-07-02T11:06:07Z 2015-07-02T11:06:07Z 2015/04/24 2014 Dissertation Wedi, OO 2014, The assessment of T-cell subsets in response to treatment in patients with breast or oesophageal cancer, MSc Dissertation, University of Pretoria, Pretoria, viewed yymmdd <http://hdl.handle.net/2263/45940> A2015 http://hdl.handle.net/2263/45940 en © 2015 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. application/pdf University of Pretoria
spellingShingle UCTD
Cancer
Immune system
Breast cancer
Treatment
The assessment of T-cell subsets in response to treatment in patients with breast or oesophageal cancer
title The assessment of T-cell subsets in response to treatment in patients with breast or oesophageal cancer
title_full The assessment of T-cell subsets in response to treatment in patients with breast or oesophageal cancer
title_fullStr The assessment of T-cell subsets in response to treatment in patients with breast or oesophageal cancer
title_full_unstemmed The assessment of T-cell subsets in response to treatment in patients with breast or oesophageal cancer
title_short The assessment of T-cell subsets in response to treatment in patients with breast or oesophageal cancer
title_sort assessment of t cell subsets in response to treatment in patients with breast or oesophageal cancer
topic UCTD
Cancer
Immune system
Breast cancer
Treatment
url http://hdl.handle.net/2263/45940