一些可引起牙龈疾病的口腔细菌可能和胰腺癌的发生相关。这项研究发表在最新一期的《Gut》杂志上。
这项发现通过检测口腔的细菌种类，为实现早期抑制目前最难治疗癌症的恶化提供了可能。胰腺癌细胞通常扩散速度很快，在诊断出有胰腺癌的病人中，5年后的存活率仅仅约为1/20。
科学家们最初比较了10例胰腺癌还未扩散的患者和10例健康人的口腔细菌种类，发现两组人群的检测结果具有显著性差异。他们在胰腺癌患者唾液中发现有31种额外的细菌，还缺少25种正常人唾液中的细菌。
然后，他们收集了28例胰腺癌患者和28例健康人的唾液样本来进一步的研究。通过研究28例患有慢性胰腺炎的人群（该类人群后期胰腺癌的发生率很高），结果显示，在6种可疑的细菌菌种中，Neisseria elongata和 Streptococcus mitis这两种细菌在患者口腔中的含量要显著低于健康人群，而Granulicatella adjacens这种细菌的含量要高于健康人群。
在超过80%的病例中，Neisseria elongata和 Streptococcus mitis这两种细菌精确反映了患病人群和健康人群的差异。
现在仍然不清楚这些特定的细菌是否和胰腺癌的形成相关，但他们的发现可以追溯到最初的研究——细菌和胰腺疾病的形成相关。
科学家们表示目前这些口腔特定细菌的含量可以用作临床早期检测胰腺癌的无创方法。（生物探索 Jun）
推荐阅读：从乔布斯离世认识胰腺癌
相关英文论文摘要：
Variations of oral microbiota are associated with pancreatic diseases including pancreatic cancer
Objective The associations between oral diseases and increased risk of pancreatic cancer have been reported in several prospective cohort studies. In this study, we measured variations of salivary microbiota and evaluated their potential associations with pancreatic cancer and chronic pancreatitis.
Methods This study was divided into three phases: (1) microbial profiling using the Human Oral Microbe Identification Microarray to investigate salivary microbiota variation between 10 resectable patients with pancreatic cancer and 10 matched healthy controls, (2) identification and verification of bacterial candidates by real-time quantitative PCR (qPCR) and (3) validation of bacterial candidates by qPCR on an independent cohort of 28 resectable pancreatic cancer, 28 matched healthy control and 27 chronic pancreatitis samples.
Results Comprehensive comparison of the salivary microbiota between patients with pancreatic cancer and healthy control subjects revealed a significant variation of salivary microflora. Thirty-one bacterial species/clusters were increased in the saliva of patients with pancreatic cancer (n=10) in comparison to those of the healthy controls (n=10), whereas 25 bacterial species/clusters were decreased. Two out of six bacterial candidates (Neisseria elongata and Streptococcus mitis) were validated using the independent samples, showing significant variation (p<0.05, qPCR) between patients with pancreatic cancer and controls (n=56). Additionally, two bacteria (Granulicatella adiacens and S mitis) showed significant variation (p<0.05, qPCR) between chronic pancreatitis samples and controls (n=55). The combination of two bacterial biomarkers (N elongata and S mitis) yielded a receiver operating characteristic plot area under the curve value of 0.90 (95% CI 0.78 to 0.96, p<0.0001) with a 96.4% sensitivity and 82.1% specificity in distinguishing patients with pancreatic cancer from healthy subjects.
Conclusions The authors observed associations between variations of patients' salivary microbiota with pancreatic cancer and chronic pancreatitis. This report also provides proof of salivary microbiota as an informative source for discovering non-invasive biomarkers of systemic diseases.
