Department of Obstetrics and Gynecology, Breast Center, University Hospital Münster, Münster, Germany.
Cancer Rep (Hoboken). 2023 Apr;6(4):e1771. doi: 10.1002/cnr2.1771. Epub 2022 Dec 19.
Ductal carcinoma in situ (DCIS) is a precursor form of breast cancer. 13%-50% of these lesions will progress to invasive breast cancer, but the individual progression risk cannot be estimated. Therefore, all patients receive the same therapy, resulting in potential overtreatment of a large proportion of patients.
The role of the tumor microenvironment (TME) and especially of fibroblasts appears to be critical in DCIS development and a better understanding of their role may aid individualized treatment.
Primary fibroblasts isolated from benign or malignant punch biopsies of the breast and MCF10DCIS.com cells were seeded in a 3D cell culture system. The fibroblasts were cultured in a type I collagen layer beneath a Matrigel layer with MCF10DCIS.com cells. Dye-quenched (DQ) fluorescent collagen I and IV were used in collagen and Matrigel layer respectively to demonstrate proteolysis. Confocal microscopy was performed on day 2, 7, and 14 to reveal morphological changes, which could indicate the transition to an invasive phenotype. MCF10DCIS.com cells form smooth, round spheroids in co-culture with non-cancer associated fibroblasts (NAFs). Spheroids in co-culture with tumor-associated fibroblasts (TAFs) appear irregularly shaped and with an uneven surface; similar to spheroids formed from invasive cells. Therefore, these morphological changes represent the progression of an in situ to an invasive phenotype. In addition, TAFs show a higher proteolytic activity compared to NAFs. The distance between DCIS cells and fibroblasts decreases over time.
The TAFs seem to play an important role in the progression of DCIS to invasive breast cancer. The better characterization of the TME could lead to the identification of DCIS lesions with high or low risk of progression. This could enable personalized oncological therapy, prevention of overtreatment and individualized hormone replacement therapy after DCIS.
导管原位癌（DCIS）是乳腺癌的前体形式。这些病变中有 13%-50%会进展为浸润性乳腺癌，但个体进展风险无法估计。因此，所有患者都接受相同的治疗，导致很大一部分患者存在潜在的过度治疗。
肿瘤微环境（TME），尤其是成纤维细胞的作用，在 DCIS 的发展中似乎至关重要，对其作用的更好理解可能有助于个体化治疗。
从良性或恶性乳房活检中分离出的原代成纤维细胞和 MCF10DCIS.com 细胞被接种到 3D 细胞培养系统中。成纤维细胞在底层的 I 型胶原层中培养，在 Matrigel 层下培养 MCF10DCIS.com 细胞。用染料猝灭（DQ）荧光胶原 I 和 IV 分别标记胶原和 Matrigel 层，以显示蛋白水解。在第 2、7 和 14 天进行共聚焦显微镜检查，以揭示形态变化，这可能表明向侵袭表型的转变。MCF10DCIS.com 细胞与非癌相关成纤维细胞（NAFs）共培养时形成光滑的圆形球体。与肿瘤相关成纤维细胞（TAFs）共培养的球体形状不规则，表面不均匀；类似于来自侵袭细胞形成的球体。因此，这些形态变化代表了原位向侵袭表型的进展。此外，TAFs 表现出比 NAFs 更高的蛋白水解活性。DCIS 细胞和成纤维细胞之间的距离随时间推移而缩小。
TAFs 似乎在 DCIS 向浸润性乳腺癌的进展中起着重要作用。对 TME 的更好描述可能导致识别出具有高或低进展风险的 DCIS 病变。这可以实现针对个体的肿瘤学治疗、避免过度治疗以及 DCIS 后的个体化激素替代治疗。
