Confirmation of human metastasis in the xenograft nude mouse model: new application for STR typing

Background and Aim: Genetic confirmation of metastasis to various tissues of the laboratory animal along with pathology and fluorescent labeling methods can provide a convenient, inexpensive, and accurate method of providing information from small tumors even fewer cells that burden such as pathology methods. Therefore, in the present study, for the first time, STR typing method was used to confirm the metastasis in different tissues of nude mice.Methods: In our previous study, the esophageal cancer cell line was cultured and ۴ x ۱۰۶ cells were injected into the nude mice to simulate the end stages of metastasis. After three months, mice were sacrificed with permission of the bioethics committee and, DNA was extracted from various mouse tissues such as lung, liver, heart, brain, kidney, spleen, adrenal glands, occipital lobe, bone marrow, and blood. The amplification of human STR loci (VWA, THO۱) and mouse (loci ۱۸-۳) were optimized separately and multiplexed. Sequencing of these STRs was performed and the presence of human STR was confirmed.Results: The presence of human DNA in xenograft tumor and mouse lung tissue was confirmed by amplification of human STR loci (VWA, THO۱). Amplification of ۱۸-۳ locus was also observed in all mouse tissue samples. Optimized multiplex-PCR showed amplification of all three loci. Sequencing results indicated the accuracy of these STR sequences. Thus, the STR typing method was able to detect the presence of metastatic human cells in mouse tissues.Conclusion: Our findings showed that the STR typing method, as a robust and inexpensive method, can confirm the presence of human metastatic cells in mouse tissues.

کلیدواژه ها:

STR typing ، metastasis ، VWA ، THO۱ ، ۱۸-۳ locus