Establishing Patient-Derived Xenograft Models

PDX samples (HCI-002, HCI-009 and HCI-010) were generated and published by Dr Alana Welm and colleagues at the University of Utah following local institutional review and patient consent. Briefly, donated primary breast tumors and metastatic breast cancer cells were freshly obtained following surgery and transplanted into cleared mammary fat pads of female immunocompromised NOD/SCID mice^{38 (link)}. For this study, we obtained 4-week-old immunocompromised NOD/SCID/gamma female mice purchased from Jackson Laboratory. The viably frozen HCI-002, HCI-009, and HCI-010 tumor samples were transplanted into the cleared inguinal 4R mammary fat pads of NOD/SCID/gamma mice. Tumor growth was monitored daily by caliper measurement in two dimensions. When tumors reached 2 cm in any dimension (HCI-002—after 8 weeks on average, HCI-009 and HCI-010—12 weeks), mice were killed, and tumor and NAT isolated from the 4R gland, and NCT from the 4L gland, and flash-frozen in liquid nitrogen. The protocols described in this section regarding animal studies were approved by the UCSF Institutional Animal Care and Use Committee.