Department of Biology, Damghan Branch, Islamic Azad University, Cheshmeh-Ali Boulevard, Sa'dei Square, P.O. Box: 3671639998, Damghan, Iran.
J Biomed Sci. 2013 Jan 30;20(1):6. doi: 10.1186/1423-0127-20-6.
Human cancer cells resemble stem cells in expression signatures leading them to share some features, most notably, self-renewal. A complex network of transcription factors and signaling molecules are required for continuance of this trait. SALL4 is a zinc finger transcriptional activator crucial for maintenance of self-renewal in stem cells; however, its expression level has not yet been elucidated in colorectal tumor cells. To determine this level and probable clinicopathological consequences, its expression was analyzed.
SALL4 expression in fresh tumoral and distant tumor-free tissues from 46 colorectal samples was compared by real-time polymerase chain reaction (PCR).
Greater than a two-fold increase in SALL4 expression was detected in 87% of tumors vs. normal related tissues. SALL4 expression was significantly correlated with tumor cell metastasis to lymph nodes, especially in moderately-differentiated tumor samples (P < 0.05). Furthermore, higher levels of SALL4 mRNA expression were significantly associated with younger than older patients with tumor cells in stages I and II (P < 0.05).
These results indicate a relationship between SALL4 expression and tumor cell metastasis to lymph nodes and consequent advancement of tumors to advanced stages III and IV. Along with the promising evidence of its role in self-renewal in various cancers, SALL4 may have a role in progression, development and maintenance of colorectal cancers.
人类癌细胞在表达特征上与干细胞相似，使它们具有一些共同特征，尤其是自我更新。维持这种特性需要一个复杂的转录因子和信号分子网络。SALL4 是一种锌指转录激活因子，对于维持干细胞的自我更新至关重要；然而，其在结直肠肿瘤细胞中的表达水平尚未阐明。为了确定这一水平及其可能的临床病理后果，分析了其表达情况。
通过实时聚合酶链反应（PCR）比较了 46 例结直肠样本中新鲜肿瘤组织和远处无肿瘤组织中的 SALL4 表达。
在 87%的肿瘤中检测到 SALL4 表达增加了两倍以上，与正常相关组织相比。SALL4 表达与肿瘤细胞向淋巴结转移显著相关，特别是在中分化肿瘤样本中（P < 0.05）。此外，高水平的 SALL4 mRNA 表达与肿瘤细胞处于 I 期和 II 期的年轻患者显著相关，而与年龄较大的患者不相关（P < 0.05）。
这些结果表明，SALL4 表达与肿瘤细胞向淋巴结转移以及肿瘤进展到晚期 III 期和 IV 期有关。鉴于其在各种癌症中自我更新作用的有希望证据，SALL4 可能在结直肠癌的进展、发展和维持中发挥作用。
