Breast cancer is the second leading cause of death in women above 60 years in the US. Screening mammography is recommended for women above 50 years; however, 22% of breast cancer cases are diagnosed in women below this age. We set out to develop a test based on the detection of cell-free RNA from saliva. To this end, we sequenced RNA from a pool of ten women. The 1254 transcripts identified were enriched for genes with an annotation of alternative pre-mRNA splicing. Pre-mRNA splicing is a tightly regulated process and its misregulation in cancer cells promotes the formation of cancer-driving isoforms. For these reasons, we chose to focus on splicing factors as biomarkers for the early detection of breast cancer. We found that the level of the splicing factors is unique to each woman and consistent in the same woman at different time points. Next, we extracted RNA from 36 healthy subjects and 31 breast cancer patients. Recording the mRNA level of seven splicing factors in these samples demonstrated that the combination of all these factors is different in the two groups (p value = 0.005). Our results demonstrate a differential abundance of splicing factor mRNA in the saliva of breast cancer patients.

中文翻译：

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唾液中丰富的剪接因子转录本作为乳腺癌的诊断工具

乳腺癌是美国 60 岁以上女性的第二大死因。建议 50 岁以上的女性进行乳房 X 光检查；然而，22% 的乳腺癌病例是在这个年龄以下的女性中诊断出来的。我们着手开发一种基于从唾液中检测无细胞 RNA 的测试。为此，我们对 10 名女性的 RNA 进行了测序。鉴定出的 1254 个转录本富含带有替代前 mRNA 剪接注释的基因。Pre-mRNA 剪接是一个严格调控的过程，它在癌细胞中的错误调节促进了癌症驱动异构体的形成。由于这些原因，我们选择将剪接因子作为乳腺癌早期检测的生物标志物。我们发现剪接因子的水平对于每个女性来说都是独一无二的，并且在同一女性的不同时间点是一致的。下一个，我们从 36 名健康受试者和 31 名乳腺癌患者中提取了 RNA。记录这些样本中七个剪接因子的 mRNA 水平表明，所有这些因子的组合在两组中是不同的（p 值 = 0.005）。我们的结果表明，乳腺癌患者唾液中剪接因子 mRNA 的丰度存在差异。