Ductal carcinoma in situ (DCIS) of the breast precedes the development of invasive breast cancer and reflects the genomic changes and protein expression profile of invasive disease. AKT1^low cancer cells (QCC) are a rare, drug-tolerant, epigenetically plastic, and quiescent cancer cell subset that we previously identified at a frequency of 0.5–1% in primary breast tumors using the marker profile: AKT^low/H3K9me2^low/HES1^high. Here we used quantitative immunofluorescence microscopy with computational image analysis to show that AKT1^low QCCs are present in DCIS from patients with and without co-existing invasive breast cancer. These data suggest that a drug-resistant, quiescent cancer cell state is present in premalignant breast lesions prior to the development of invasive disease. These findings warrant further study of whether AKT1^low QCCs contribute to invasive tumor development and recurrence, similar to their role in more advanced malignancy.

乳腺导管原位癌（DCIS）早于浸润性乳腺癌的发展，并反映了浸润性疾病的基因组变化和蛋白质表达谱。AKT1^低癌细胞（QCC）是一种罕见的，药物耐受的，表观遗传的和静止的癌细胞亚群，我们先前使用以下标记图谱在原发性乳腺肿瘤中发现的频率为0.5–1％：AKT^低/ H3K9me2^低/ HES1^高。在这里，我们使用定量免疫荧光显微镜与计算图像分析来显示AKT1^低DCIS中存在或不存在浸润性乳腺癌的患者中存在QCC。这些数据表明，在浸润性疾病发展之前，恶性前乳腺病变中存在一种耐药的，静态的癌细胞状态。这些发现需要进一步研究AKT1^低QCC是否有助于浸润性肿瘤的发展和复发，类似于它们在更高级的恶性肿瘤中的作用。