Towards establishing extracellular vesicle-associated RNAs as biomarkers for HER2+ breast cancer

Extracellular vesicles (EVs) are emerging as key players in breast cancer progression and hold immense promise as cancer biomarkers. However, difficulties in obtaining sufficient quantities of EVs for the identification of potential biomarkers hampers progress in this area. To circumvent this obstacle, we cultured BT-474 breast cancer cells in a two-chambered bioreactor with CDM-HD serum replacement to significantly improve the yield of cancer cell-associated EVs and eliminate bovine EV contamination. Cancer-relevant mRNAs BIRC5 (Survivin) and YBX1, as well as long-noncoding RNAs HOTAIR, ZFAS1, and AGAP2-AS1 were detected in BT-474 EVs by quantitative RT-PCR. Bioinformatics meta-analyses showed that BIRC5 and HOTAIR RNAs were substantially upregulated in breast tumours compared to non-tumour breast tissue, warranting further studies to explore their usefulness as biomarkers in patient EV samples. We envision this effective procedure for obtaining large amounts of cancer-specific EVs wil...细胞外囊泡（Extracellular vesicles, EVs）作为乳腺癌进展的关键调控因子逐渐受到关注，并在癌症生物标志物领域展现出巨大应用前景。然而，难以获取足够数量的细胞外囊泡以鉴定潜在生物标志物的问题，阻碍了该领域的研究进展。为克服这一障碍，我们使用CDM-HD血清替代物，在双室生物反应器中培养BT-474乳腺癌细胞，显著提升了癌细胞相关细胞外囊泡的产出率，并消除了牛源细胞外囊泡污染。通过定量逆转录聚合酶链反应（quantitative RT-PCR），我们在BT-474来源的细胞外囊泡中检测到癌症相关mRNA BIRC5（Survivin）、YBX1，以及长链非编码RNA HOTAIR、ZFAS1与AGAP2-AS1。生物信息学荟萃分析结果显示，相较于非肿瘤乳腺组织，BIRC5与HOTAIR RNA在乳腺肿瘤中显著上调，这一结果值得开展进一步研究，以探索二者在患者来源细胞外囊泡样本中作为生物标志物的应用价值。我们设想这一可获取大量癌症特异性细胞外囊泡的高效实验流程将...