Cancer-associated fibroblast driven paracrine IL-6/STAT3 signalling promotes migration and dissemination in invasive lobular carcinoma

Invasive Lobular Carcinoma (ILC) is an under-studied yet common subtype of breast cancer. A key feature of ILC tumours, due to their single-file invasive growth pattern, is a high stromal content and in particular, an abundance of cancer-associated fibroblasts (CAFs). We identified that IL-6 secreted from primary ILC patient-derived CAFs drives STAT3 activation in ILC cell lines and found that IL6, STAT3, pSTAT3 and subsequent downstream gene expression induced by IL-6 within CAF conditioned media is upregulated in ILC tumours compared to Invasive Ductal Carcinoma tumours, the most common subtype of breast cancer. This dataset contains 3`-mRNAseq data from ILC cell lines (SUM44PE and MDA-MB-134VI) and patient-derived organoids (HCI-013 and HCI-018) stimulated with either recombinant human IL-6 (10 ng/ml) for 24 hours or 1 week or SUM44PE cells stimulated with CAF conditioned media (CAF CM)collected from ED26 primary ILC CAFs (characterised here: doi.org/10.3390/cancers14040904) +/- an IL-6 neutralising antibody. RNA was extracted using Qiagen RNeasy mini-kit and libraries were prepared using QuantSeq 3’ mRNA-Seq Library Prep Kit (FWD) for Illumina (Lexogen Inc, #015). Invasive Lobular Carcinoma cell lines (SUM44PE and MDA-MB-134VI) or patient-derived organoids (HCI-013 and HCI-018) stimulated with primary ILC CAF conditioned media for 24 hours +/- anti-IL-6 neutralising antibody (SUM+CM experiments) or + 10 ng/ml recombinant human IL-6 for 24 hours (+ IL-6 experiments) or 1 week.