Objective To investigate the effect of juxtaposed with another zinc finger 1 (JAZF1) on proliferationand apoptosis of papillary thyroid carcinoma (PTC) BCPAP cells and its possible mechanism. Methods BCPAP cellswere divided into negative control group (NC group), Adv-GFP group and Adv-JAZF1-GFP group, which were not infectedor infected with recombinant adenoviruses Adv-GFP or Adv-JAZF1-GFP, respectively. The total RNA and protein of eachgroup were extracted 48 h after infection. The relative JAZF1 mRNA and protein expressions were determined by real-timefluorescence quantitative PCR (qRT-PCR) and Western blotting, and the growth and proliferation of cells were examinedby the MTT and clone formation assays. Annexin V-FITC/ PI double staining was used to determine the apoptosis of cells ineach group by flow cytometry. The relative protein expressions of Bcl-2, Bax, PPAR-γ, PI3K, Akt and p-Akt weredetermined by Western blotting. Results Compared with the NC and Adv-GFP groups, the relative JAZF1 mRNA andprotein expression in the experimental group was significantly upregulated ( P < 0. 001), the proliferation ability wassignificantly inhibited ( P < 0. 01), and the clone formation ability was decreased ( P < 0. 001).The Annexin V-FITC/ PIdouble staining results showed that the apoptosis rate of the Adv-JAZF1-GFP group (23. 02 ± 0. 35%) was significantlyincreased than the NC group (8. 63 ± 0. 40%) and the Adv-GFP group (7. 95 ± 0. 32%) ( P < 0. 001). Compared withNC and Adv-GFP groups, the expression level of Bcl-2 was significantly downregulated by 66. 0% and the expression of Baxwas upregulated by 64. 8% in the Adv-JAZF1-GFP group ( P < 0. 001). Furthermore, the p-PI3K/ PI3K and pAkt/ Aktratios were significantly decreased in the experimental group compared with the controls ( P < 0. 001). Conclusions JAZF1 may play an important role in the development of papillary thyroid cancer by regulating the Bcl-2/ Bax pathway topromote apoptosis and by regulating the PI3K/ Akt signaling pathway to inhibit the proliferation of BCPAP cells.