Gene targeting strategy for B-hEPCAM LLC1 cells. The exogenous promoter and human EPCAM coding sequence was inserted to replace part of murine exon 4 and all of exons 5~7. The insertion disrupts the endogenous murine Epcam gene, resulting in a non-functional transcript.

Subcutaneous homograft tumor growth of B-hEPCAM LLC1 cells. B-hEPCAM LLC1 cells (2x10⁵) were subcutaneously implanted into C57BL/6 mice (female, 11-week-old, n=6). Tumor volume and body weight were measured thrice a week. (A) Average tumor volume ± SEM. (B)  Body weight (Mean± SEM). Volume was expressed in mm³ using the formula: V=0.5 X long diameter X short diameter². As shown in panel A, B-hEPCAM LLC1 cells were able to establish tumors in vivo and can be used for efficacy studies.

B-hEPCAM LLC1 cells were subcutaneously transplanted into C57BL/6 mice (n=6). At the end of the experiment, tumor cells were harvested and assessed for human EPCAM expression by flow cytometry. As shown, human EPCAM was highly expressed on the surface of tumor cells. Therefore, B-hEPCAM LLC1 cells can be used for in vivo efficacy studies of novel EPCAM therapeutics.