Das Srustidhar, Batra Surinder K
Department of Biochemistry and Molecular Biology, Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, 985870 Nebraska Medical Center, Omaha, NE 68198-5870, U.S.A.
Curr Pharm Des. 2015;21(10):1249-55. doi: 10.2174/1381612821666141211115234.
Pancreatic cancer, often considered a metastatic disease at the time of clinical diagnosis due to lack of any reliable early diagnostic marker(s), is refractory to conventional chemo- and radiotherapy and has a dismal 5-year survival rate of only 6%. Although surgical removal of the primary tumor is considered to be curative, the 5-year survival rate is no more than 20% even in patients with clear resection margins (R0). The recurrence of local and metastatic disease (primarily liver metastasis) post resection is considered to be the leading cause of mortality in these patients. In addition, instances of metastatic disease without any local recurrence post resection have also been observed. Cancer metastasis is the primary cause of mortality in cancer patients and is classically viewed as a late event during the progression of the disease, which is supported by the genetic studies used to understand the evolution of pancreatic cancer. However, this view has recently been challenged by studies using mathematical modeling and genetically labeled mouse models of pancreatic cancer to understand the dynamics of tumor cell dissemination and epithelial to mesenchymal transition (EMT) of tumor cells well before the primary tumor is formed. Given that EMT is a hallmark process that initiates the metastatic seeding of cancer cells and the dismal prognosis of pancreatic cancer patients even after efficient removal of the primary tumor (99.9%), an early dissemination hypothesis of cancer cells cannot be undermined. In this review, we will discuss the current views regarding pancreatic cancer metastasis with particular emphasis on the epithelial to mesenchymal transition, its influence on the selection of patients for surgical resection and the therapeutic intervention.
胰腺癌在临床诊断时通常被认为是一种转移性疾病,因为缺乏任何可靠的早期诊断标志物,对传统的化疗和放疗具有抗性,5年生存率仅为6%,令人沮丧。尽管手术切除原发性肿瘤被认为是可治愈的,但即使在切缘清晰(R0)的患者中,5年生存率也不超过20%。切除术后局部和转移性疾病(主要是肝转移)的复发被认为是这些患者死亡的主要原因。此外,也观察到了切除术后无任何局部复发的转移性疾病病例。癌症转移是癌症患者死亡的主要原因,传统上被视为疾病进展过程中的晚期事件,用于理解胰腺癌演变的基因研究支持了这一观点。然而,最近这一观点受到了一些研究的挑战,这些研究使用数学建模和胰腺癌基因标记小鼠模型来了解肿瘤细胞播散的动态以及在原发性肿瘤形成之前肿瘤细胞的上皮-间质转化(EMT)。鉴于EMT是启动癌细胞转移播种的标志性过程,并且即使在有效切除原发性肿瘤(99.9%)后胰腺癌患者的预后仍然很差,癌细胞早期播散的假说不容忽视。在这篇综述中,我们将讨论关于胰腺癌转移的当前观点,特别强调上皮-间质转化、其对手术切除患者选择和治疗干预的影响。