Isolation and Identification of Pancreatic Cancer Stem Cells from BxPC-3 Cell Line Cultured in Serum-Free Medium

Abstract

[目的]從人胰腺癌細胞系BxPC-3中分離并鑒定胰腺癌干細胞。[方法]用無血清培養基培養人胰腺癌BxPC-3得到腫瘤細胞球。將腫瘤細胞球傳代擴增,觀察各傳代后細胞成球能力;并用含血清培養基誘導促使其分化;蛋白印跡法測定腫瘤干細胞特異性轉錄因子OCT-4蛋白表達情況,并將腫瘤細胞球細胞植入NOD/SCID小鼠皮下,觀察移植瘤的形成。[結果]在無血清培養基中,BxPC-3細胞能形成少量腫瘤細胞球,具有很強的自我更新能力,成球能力隨著球體細胞傳代次數的增加而增加。在含血清環境中,球體細胞逐漸分化而呈貼壁生長。腫瘤細胞球OCT-4蛋白表達明顯高于BxPC-3貼壁細胞。1×104個球體細胞即能在NOD/SCID小鼠皮下成瘤。[結論]無血清培養能夠有效的分離和擴增人胰腺癌細胞系BxPC-3的腫瘤干細胞。 [Purpose] To isolate and identify pancreatic cancer stem cells from human pancreatic cancer cell line BxPC-3. [Method]BxPC-3 cells were cultured in serum-free medium to derive tumor spheres. Tumor spheres were then expanded and passage to estimate the potency of sphere-forming,then cultured in serumcontaining medium to induce their differentiation. The protein expression of stem cell related transcript factor OCT-4 was evaluated by western blot. The tumorigenesis of the sphere-forming cells was observed in subcutaneously implanted NOD/SCID mice models. ［Results］ A few of floating tumor spheres were isolated and expanded in serum-free medium. These tumor spheres attached to the bottom of culture plates and began to differentiate when cultured in serum-containing medium. The protein expression of OCT-4 was significantly higher in sphere-forming cells of BxPC-3 than that attached cells. Only one thousand spheroid cells can form tumor in NOD/SCID mice. ［Conclusion］ Serum-free medium culture is an effective way to isolate and expand the pancreatic cancer stem cell from BxPC-3.