胰腺癌诊断与治疗研究喜讯频出
2014/08/06
有人说:“如果说肝细胞癌是’癌中之王’,胰腺癌就是’王中之王’”,可见其高度恶性、侵袭性和致死性,晚期患者治疗尤为困难棘手,预后非常恶劣。令人庆幸的是,近期有关胰腺癌研究喜讯频出,除了解开多种发病机制,更是有很多诊断和治疗手段不断涌出,这对于胰腺癌患者无疑是天大的喜讯。


乔布斯因胰腺癌病逝

有人说:“如果说肝细胞癌是’癌中之王’,胰腺癌就是’王中之王’”,可见其高度恶性、侵袭性和致死性,晚期患者治疗尤为困难棘手,预后非常恶劣。令人庆幸的是,近期有关胰腺癌研究喜讯频出,除了解开了多种发病机制,更是有很多诊断和治疗手段不断涌出,这对于胰腺癌患者无疑是天大的喜讯。下面就让我们来一起回顾一下吧。

机理:遗传标志物和治疗靶点

遗传风险标志物:8月3日,来自美国Dana-Farber癌症研究所的科学家们在《Nature Genetics》杂志发表的文章发现了五个新的胰腺癌遗传风险标志物。该研究分析了来自7,683名胰腺癌患者和14,397名非胰腺癌对照者的DNA。科学家们利用测序技术检测了700,000多个基因组位点,这些位点已知有单核苷酸多态性(SNPs)。每个SNP或标记相关的风险在很大程度上是独立的和附加的,所以未来它们可用以试图找出普通人群中的胰腺癌高风险个体。

治疗靶点:7月1日,发表在《Cancer Research》上的一项研究发现了一种蛋白质--半乳糖凝集素1(galectin-1)可作为胰腺癌可能的治疗靶点。半乳糖凝集素1在正常胰腺中没有被发现,但在胰腺肿瘤中强烈表达。这项研究观察到,消除小鼠体内半乳糖凝集素-1没有有害的后果,这表明它可能是一个安全的治疗靶标,没有不利影响。

突变基因:5月25日,加州大学医学院圣地亚哥分校医学院研究人员发现了的一种突变基因UPF1,它是罕见胰腺癌形式——腺鳞癌(ASC)的第一个已知的唯一分子标签。ASC病例并不多见,但通常比较常见类型胰腺癌的有较差的预后。研究人员说,ASC胰腺肿瘤的UPF1基因具有体细胞和非遗传性突变,涉及一个高度保守的RNA降解途径。该研究结果发表《Nature Medicine》上。

诊断:新型设备和技术


信用卡般大小诊断设备:7月下旬,美国华盛顿大学的研究人员开发出一种如信用卡般大小的低成本设备,可以帮助病理学家更早、更快地诊断出胰腺癌,使得临床医生无需用手处理组织,只用注射器针头取得组织活样输入该仪器原型,其即可依靠微流体的属性执行处理活检组织的基本步骤。

研究人员说,这项技术可能作为一个非处方工具包处理活检切片,然后将此信息从偏远地区发送给病理学家以寻找癌症迹象。此外,它有可能减少诊断癌症需要的时间,而仅需短短的几分钟。他们将于近期为相关的第一代设备及未来的技术进步申请专利。

短碳纳米管:5月29日,来自美国莱斯大学等处的研究人员发表在《Journal of Materials Chemistry B》杂志上的一项研究开发出了一种特殊定制的短碳纳米管,其或可以将药物运输之胰腺癌细胞中对癌细胞进行靶向杀灭作用。

研究人员称,这种碳纳米管,其可以以其较小的尺寸顺利通过机体的防御系统成功达到胰腺癌细胞,对癌细胞实施攻击。这项研究中研究者主要致力于改善针对胰腺癌的药物运输疗法,下一步研究人员将在小鼠机体中检测这种新型的药物运输系统,研究者希望尽快进入临床试验阶段,为开发治疗胰腺癌的新型靶向疗法提供帮助。

微流体装置:早在今年3月发表在世界肠胃病学领域排名第一的《Gastroenterology》杂志上的一项研究使用了一种最新水平的微流体装置,捕捉33名具有早期胰腺病变、但没有癌症临床诊断患者的循环胰腺上皮细胞。结果表明,通过目前的临床检查如CT或MRI扫描,可以检测在肿瘤形成之前播种于血流中的循环胰腺细胞,这可能是癌症的一个早期迹象。 此外美国微生物学会的消息,研究发现胰腺癌病人的口腔微生物组成模式与健康对照之间存在明显的差异。这一发现将会对胰腺癌的早期诊断提供巨大的帮助。

治疗:新药和新制剂

雷帕霉素:日前,发表在国际杂志《Gut》上的一篇研究论文中,来自英国格拉斯格大学等处的研究人员发现了一种老药(雷帕霉素)可以新用。此前临床试验中,当研究者给所有患者服用雷帕霉素时,并没有发现其可以有效抑制胰腺癌的发展。在这项研究中,研究人员发现,当给予因PTEN突变而发生胰腺癌的小鼠雷帕霉素之后,研究者发现雷帕霉素可以有效阻断癌细胞的扩散和发展,在某些小鼠机体中,雷帕霉素甚至可以促进肿瘤死亡。

雷公藤提取物:6月1日,美国明尼苏达大学研究人员发表在《American Journal of Physiology》上的一项研究发现雷公藤提取物能够抑制胰腺癌细胞生长和存活。GRP78是能保护癌细胞免于死亡的蛋白质,在癌症细胞和组织中比在正常器官中更丰富,并且被认为在帮助胰腺癌细胞生存和发展中发挥作用。尽管GRP78的表达增加赋予肿瘤细胞生存优势,但长时间暴露在雷公藤甲素下能诱导慢性ER应激,最终导致癌细胞死亡。在这种情况下,由雷公藤甲素活化ER应激途径抑制GRP78提供了抑制胰腺癌细胞生长和存活的一个新颖机制。


雷公藤

儿茶素:5月18日,《Metabolomics》杂志在线发表的一项研究发现儿茶素(EGCG,绿茶中的活性成分)可以通过抑制与癌症有关的酶LDHA的表达,打乱了整个细胞代谢网络“通量”的平衡,改变胰腺癌细胞的代谢,从而降低患癌症的风险。


南瓜:此外,之前美国科罗拉多大学的科学家研究发现,南瓜能够减少胰腺中的癌细胞繁殖,常吃有助于预防癌症。 科学家解释说,癌细胞无法产生自身所需要的糖,使癌细胞不得不从其他物质中吸收糖分,而南瓜中所含物质不会给胰腺中的癌细胞提供所需要的糖分,从而会减少其癌细胞的存活率。

小编寄语:胰腺癌是一种恶性程度很高,诊断和治疗都很困难的消化道恶性肿瘤,乔布斯就是因为它而病逝的,目前仍然是医学界面临的一个重大难题和严峻挑战。只有不断阐明该疾病多方向的病理机制,发明更多用于早期快速准确的诊断方法,找到适合不同病人的特异性药物靶点,才能真正的为胰腺癌患者解除心头的忧患。

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