Identification By MRNA Differential Display Of Genes Possibly Associated With Metastasis Of A Mouse Mammary Cancer MA891

Tumor metastasis is the major cause of death in cancer patients. It has been a "hot spot" in the field of cancer research. Many factors have been found to be associated with tumor metastasis, such as adhesive molecules, metastasis-related genes, invasive enzymes and their antagonists, and tumor angiogenesis. That so many factors are related to tumor metastasis implicates that the tumor metastasis is a very sophisticated process. Many laboratories are engaged in identification of rumor metastasis associated factors.We have previously reported that in vitro treatment with interferons of MA891, a spontaneous mouse mammary tumor capable of metastasizing to the lungs upon subcutaneous inoculation, could modulate its metastatic potential. EFN-γ increases while IFN-α decreases lung metastasis, implying that metastasis related gene(s) are differentially expressed when the cells are treated with these two EFNs. To identify the metastasis related genes, mRNA differential display technique was adopted.Total RNA was extracted from MA891 cells that had been treated with 200u/ml human rIFN-α or rIFN-γ for 48 h. All the primer pairs (T12MA/C/G/T × 20 arbitrary primers) were used in the differential display, which would cover theoretically over 95% of mRNA. All the RT-PCR were done twice to minimize false positive differentially expressed bands. Twelve bands were separated from the gel and their cDNA fragments were extracted which were referred to as T2α, T2γ, C4α, T5α1, T5α2, T6α, T11γ, G15γ, T15α, T15γ, T16γ, and T17α according to their primers and RNA sources. Except for T15α and T15γ that failed to reamplicate, the other 10 cDNA fragments were reamplicated, cloned, and analyzed by Northern blot. T2γ, C4α, T11γ, and G15γ were further shown to be differentially expressed...