FIGURE 2.
Expression pattern of squamous cell markers in HCK1T cells conditionally expressing E6 and E7 of human papillomavirus (HPV)16 or HPV18, MYCT58A, and KRASG12V (EMR) with or without cellular factors possibly affecting cell lineage. A‐C, Western blot analyses for endogenous expression levels of ΔNp63α, cytokeratin (CK)14, CK18, and CK7. A, C, HCK1T‐tre16EMR or ‐tre18EMR with FOXA2, microRNA targeting SMAD4 (SMAD4mi), or POU5F and HNF4α (PH). B, HCK1T‐tre16EMR and HCK1T‐tre18EMR were serially transduced with a FOXA2 expressing lentivirus and a SMAD4mi expressing lentivirus (+F + S). The whole‐cell lysates were obtained from the indicated cells cultured in the presence or absence of doxycycline (DOX; 1000 ng/ml) for 5 d. Vinculin was detected as a loading control. Levels of lineage‐specific markers in the indicated cells relative to that in HCK1T‐tetOFF cells are indicated at the bottom. Average of three independent experiments is shown. D, E, Sulforhodamine B assay for cell proliferation. Cells were cultured in the presence (+) or absence (−) of 1000 ng/mL DOX. Mean value of at least three independent experiments was plotted with ± SD. Student’s t test was used to calculate the P value; *P ≤ .05, **P ≤ .01, ***P ≤ .001. ns, no significant difference (P > .05)