The molecular pathology of metastasis with reference to the SL 12 murine lymphoma model

Wong, Wing Zou (1999) The molecular pathology of metastasis with reference to the SL 12 murine lymphoma model. MD thesis, University of Glasgow.

Abstract

The SL 12 murine T-lymphoma cell line established by MacLeod et. al., has two sister clones SL 12.3 and SL 12.4. These two cell lines with similar amount of DNA have been shown to have different surface antigens, tumourigenicity and pattern of metastasis. This was thought to be due to differential expression of genes, either repressed or activated, by the two cell lines. This study has re-established the SL 12.3 and SL 12.4 cell lines, hi tissue culture, both cell lines grow well in suspension in modified Dulbecco medium (DMEM). SL 12.4 cells grow in clumps whereas SL 12.3 cells grow diffusely in vitro. Growth curves of SL 12.3 and SL 12.4 cell lines over five days show similar characteristics but with wide variation in SL 12.4 cell counts resulting in large standard error of mean. Clumping of SL 12.4 cells may be responsible for this variation due to cell counting difficulties. Therefore, although growth curves between the two cell lines are shown to be similar', it is not possible to conclude that the growth rates and cell doubling times are identical. In macroscopic studies, mice injected with 106 SL 12.3 cells via the tail vein deteriorate over a median of 17 days (range 11 to 24 days). All mice (100%) have huge hepatosplenomegaly. On the other hand, only one mouse (9.1%) injected with similar number of SL 12.4 cells deteriorated with metastases at 22 days. When the inoculum of SL 12.4 cells was increased to 107 cells, 78.5% of mice developed metastasis over a median of 48 days (range 31-56 days). Metastases were seen in ovaries, kidneys and lymph nodes macroscopically in contrast to SL 12.3 cells. Microscopically, it was found that both SL 12.3 and SL 12.4 cells were similarly distributed in various organs that were not involved macroscopically indicating that the observed differing pattern of metastasis is more likely to be due to differential 'in-organ' growth rates rather than cells homing to a particular site after injection. This hypothesis was further investigated by in vivo cellular tracking studies using 125IUDR labelled cells. The mean number of SL 12.4 cells per gram of wet tissue was found to be higher in ovarian tissues at 60 minutes post injection but after 3 hours post injection, both cell lines showed no significant differences in tissue distribution. This again suggested no evidence of a 'homing' phenomenon. The percentage of incorporation was poorly reproducible and this markedly reduced the sensitivity of the study producing wide variation making the data interpretation difficult and therefore, conclusion based in the data non-valid. Molecular characterisation of the two cell lines was performed using the technique of Differential Display to further investigate the possibility of differential gene expression or repression that could be responsible for the differing in vivo growth rates. (Abstract shortened by ProQuest.).

• Item Type: Thesis (MD)
• Qualification Level: Doctoral
• Additional Information: Research was conducted in the Department of Surgery, Keele University, North Staffordshire Hospital, Stoke-on-Trent.
• Keywords: Molecular biology, cellular biology.
• Subjects: Q Science > QH Natural history > QH345 Biochemistry
• Colleges/Schools: College of Medical Veterinary and Life Sciences
• Supervisor's Name: Deakin, Mr. Mark
• Date of Award: 1999
• Depositing User: Enlighten Team
• Unique ID: glathesis:1999-71609
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 17 May 2019 09:31
• Last Modified: 19 Oct 2022 10:02
• Thesis DOI: 10.5525/gla.thesis.71609
• URI: https://theses.gla.ac.uk/id/eprint/71609