Pancreatic stellate cell secreted IL-6 stimulates STAT3 dependent invasiveness of pancreatic intraepithelial neoplasia and cancer cells

Nagaraj S. Nagathihalli, Jason A. Castellanos, Michael N. Van Saun, Xizi Dai, Mahogany Ambrose, Qiaozhi Guo, Yanhua Xiong, Nipun B. Merchant

Research output: Contribution to journalArticlepeer-review

39 Scopus citations

Abstract

Pancreatic ductal adenocarcinoma (PDAC) is a dynamic tumor supported by several stromal elements such as pancreatic stellate cells (PSC). Significant crosstalk exists between PSCs and tumor cells to stimulate oncogenic signaling and malignant progression of PDAC. However, how PSCs activate intercellular signaling in PDAC cells remains to be elucidated. We have previously shown that activated signal transducer and activator of transcription 3 (STAT3) signaling is a key component in the progression of pancreatic neoplasia. We hypothesize that PSC secreted IL-6 activates STAT3 signaling to promote PanIN progression to PDAC. Human PDAC and mouse PanIN cells were treated with PSC-conditioned media (PSC-CM), and phosphoand total-STAT3 levels by immunoblot analysis were determined. IL-6 was quantified in PSC-CM and cell invasion and colony formation assays were performed in the presence or absence of a neutralizing IL-6 antibody and the JAK/STAT3 inhibitor AZD1480. Serum from Ptf1aCre/+;LSL-KrasG12D/+;Tgfbr2flox/flox (PKT) and LSL-KrasG12D/+; Trp53R172H/+; Pdx1Cre/+ (KPC) mice demonstrated increased levels of IL-6 compared to serum from non-PDAC bearing KC and PK mice. PSC secreted IL-6 activated STAT3 signaling in noninvasive, precursor PanIN cells as well as PDAC cells, resulting in enhanced cell invasion and colony formation in both cell types. There was a significant positive linear correlation between IL-6 concentration and the ratio of phosphorylated STAT3/total STAT3. IL-6 neutralization or STAT3 inhibition attenuated PSC-CM induced activation of STAT3 signaling and tumorigenicity. These data provide evidence that PSCs are directly involved in promoting the progression of PanINs towards invasive carcinoma. This study demonstrates a novel role of PSC secreted IL-6 in transitioning noninvasive pancreatic precursor cells into invasive PDAC through the activation of STAT3 signaling.

Original languageEnglish (US)
Pages (from-to)65982-65992
Number of pages11
JournalOncotarget
Volume7
Issue number40
DOIs
StatePublished - 2016

Keywords

  • IL-6
  • PanIN
  • Pancreatic cancer
  • Pancreatic stellate cells
  • STAT3

ASJC Scopus subject areas

  • Oncology

Fingerprint

Dive into the research topics of 'Pancreatic stellate cell secreted IL-6 stimulates STAT3 dependent invasiveness of pancreatic intraepithelial neoplasia and cancer cells'. Together they form a unique fingerprint.

Cite this