[Growing characteristic of breast adenocarcinoma suicide gene cell line T47D-tk and construction of subcutaneous xenografts].
OBJECTIVE
To further identify the breast adenocarcinoma cell line T47D-tk stably expressing the suicide gene HSV1-tk, observe its growing characteristics, and establish an animal model of implanted breast adenocarcinoma.


METHODS
Retroviral vector of HSV1-tk gene and breast carcinoma cell line T47D-tk stably expressing the HSV1-tk gene were established. Breast carcinoma cells of the lines T47D and T47D-tk were cultured, and observed by inverted microscope. Growth curve was drawn. Genomic DNA of T47D-tk cells was extracted, and amplified by PCR with HSV1-tk and HSV1-tk P2 as primers. Agarose gel electrophoresis was used to identify the HSV1tk gene. Suspensions of T47D and T47D-tk cells were inoculated subcutaneously at bilateral roots of foreleg of female BALB/c nude mice respectively. The growth of tumor was observed every day.


RESULTS
PCR showed 1131 bp fragment in the T47D-tk genome, but not in the T47D genome. The numbers of growing T47D cells on days 3, and 7 were (10.00 +/- 1.30) x 10(3) and (19.25 +/- 0.66) x 10(3) respectively, not significantly different from those of the T47D-tk cells [(10.25 +/- 0.90) x 10(3) and (19.00 +/- 1.80) x 10(3) respectively, both P > 0.05]. The time needed for tumor formation after the inoculation of T47D cells was (9.67 +/- 0.33) d, not significantly different from that of the T47D-tk cells [(9.83 +/- 0.48) d, P > 0.05]. The tumor size 19 days after inoculation of the T47D cells was (72.17 +/- 25.88) mm(3), not significantly different from that of the T47D-tk cells [(70.66 +/- 22.16) mm(3), P > 0.05].


CONCLUSIONS
The T47D-tk cells have integrated the HSV1-tk gene without changing its growing characteristics. An animal model of implanted breast cancer has been successfully established. The T47D and T47D-tk subcutaneous xenografts offer the foundation for further study of gene imaging and gene therapy.
Xu
Wen-Gui
WG
PET center, Tianjin Cancer Hospital & Institute, Tianjin Medical University, Tianjin 300060, China. wenguixy@tom.com
Yang
Kun
K
Fang
Na
N
Dai
Dong
D
Yu
Jin-Pu
JP
Wei
Feng
F
Song
Xiu-Yu
XY
Zhu
Yan-Jia
YJ
Wang
Jian
J
Men
Xiao-Yuan
XY
Zhang
Ying
Y
D000818:Animals; D001943:Breast Neoplasms / Q000235:genetics*; D045744:Cell Line, Tumor; D005260:Female; D018014:Gene Transfer Techniques; D041722:Genes, Transgenic, Suicide / Q000235:genetics*; D015316:Genetic Therapy; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D014162:Transfection; D023041:Xenograft Model Antitumor Assays