Tumor metastasis occurs naturally in pancreatic cancer, and the efficacy of chemotherapy is usually poor. Precision medicine, combining downregulation of target genes with chemotherapy drugs, is expected to improve therapeutic effects. Therefore, we developed a combined therapy of micro RNA ‐21 antisense oligonucleotides ( ASO ‐miR‐21) and gemcitabine (Gem) using a targeted co‐delivery nanoparticle ( NP ) carrier and investigated the synergistic inhibitory effects on pancreatic cancer cells metastasis and growth. Polyethylene glycol–polyethylenimine–magnetic iron oxide NP s were used to co‐deliver ASO ‐miR‐21 and Gem. An anti‐ CD 44v6 single‐chain variable fragment (scFv _{CD 44v6} ) was used to coat the particles to obtain active and targeted delivery. Our results showed that the downregulation of the oncogenic miR‐21 by ASO resulted in upregulation of the tumor‐suppressor genes PDCD 4 and PTEN and the suppression of epithelial–mesenchymal transition, which inhibited the proliferation and induced the clonal formation, migration, and invasion of pancreatic cancer cells in vitro . The co‐delivery of ASO ‐miR‐21 and Gem induced more cell apoptosis and inhibited the growth of pancreatic cancer cells to a greater extent than single ASO ‐miR‐21 or Gem treatment in vitro . In animal tests, more scFv _{CD 44v6} ‐ PEG ‐polyethylenimine/ ASO ‐magnetic iron oxide NP /Gem accumulated at the tumor site than non‐targeted NP s and induced a potent inhibition of tumor proliferation and metastasis. Magnetic resonance imaging was used to observed tumor homing of NP s. These results imply that the combination of miR‐21 gene silencing and Gem therapy using an scFv‐functionalized NP carrier exerted synergistic antitumor effects on pancreatic cancer cells, which is a promising strategy for pancreatic cancer therapy.

The molecular mechanism of perineural invasion (PNI) is unclear, and insufficient detection during early-stage PNI in vivo hampers its investigation. We aimed to identify a cytokine paracrine loop between pancreatic ductal adenocarcinoma (PDAC) cells and nerves and established a noninvasive method to monitor PNI in vivo.

Fibroblast activation protein (FAP) is a serine protease that has been reported in fibroblasts and some carcinoma cells, which correlates with poor patient outcomes. FAP can be induced under hypoxia which is also vital in the malignant behaviors of cancer cells. However, the role of FAP and its correlation with hypoxia has not been investigated in HCC cancer cells. In tissues from post-surgical HCC patients in our center, we adopted immunohistochemistry staining (IHC), western blot and quantitative RT-PCR to detect the expression levels of FAP and the hypoxia related marker, hypoxia inducible factor 1α (HIF-1α). X-tile software was used for the determination of high and low expression of FAP and HIF-1α after the IHC analysis. Clinicopathological analysis, Kaplan-Meier analysis and Cox regression model were performed. In-vitro experiments were performed to confirm the relationship between FAP and hypoxia in HCC cancer cell lines (HepG2, Huh7 and MHCC97H). Results revealed that expression levels of FAP and HIF-1α were significantly correlated (Pearson r² = 0.2753, p < 0.0001) in IHC analysis of the 138-patient cohort. Western blot and quantity RT-PCR indicated parallel changes in 11 post-surgical fresh frozen tissues. The HIF-1α and FAP expression were associated with serum AFP, TNM, tumor size and vascular invasion. Cox regression analysis showed that HIF-1α/ FAP combination were the independent predictor for overall survival (OS) and time-to-recurrence (TTR) in post-surgical HCC patients. Kaplan-Meier analyses revealed that the patient with high levels of HIF-1α, FAP and combined HIF-1α/FAP had the shortest OS and TTR. In-vitro experiments showed that FAP was increased in hypoxic HCC cancer cell lines in parallel with that of HIF-1α and three EMT markers (E-cadherin, Snail and TWIST). In conclusion, the up-regulation of FAP in HCC cancer cells under hypoxia can be indicative of poor prognosis in patients.

Tumor‐associated macrophages (TAMs) are abundant population of inflammatory cells which play an essential role in remodeling tumor microenvironment and tumor progression. Previously, we found the high density of TAMs was correlated with lymph node metastasis and poor prognosis in pancreatic ductal adenocarcinoma (PDAC). Therefore, this study was designed to investigate the mechanisms of interaction between TAMs and PDAC. THP‐1 monocytes were the exposure to conditioned media (CM) produced by PDAC cells; then, monocyte recruitment and macrophage differentiation were assessed. CM from PDAC attracted and polarized THP‐1 monocytes to tumor‐driven like macrophages. mRNA expression cytokine profiling and ELISA identified the IL‐8 secretion was increasing in tumor‐driven like macrophages, and STAT3 pathway was involved. Addition of exogenous recombinant human IL‐8 promoted PDAC cells motility in vitro and metastasis in vivo via upregulating Twist expression, which mediated epithelial‐mesenchymal transition in cancer cells. What is more, IL‐8 expression level in tumor stroma by immunohistochemical analysis was related to lymph node metastasis, the number of tumor CD68 but not CD163 positive macrophages and patient outcome. Taken together, these findings shed light on the important interplay between cancer cells and TAMs in tumor microenvironment and suggested that IL‐8 signaling might be a potential therapeutic target for PDAC.

Matrix metalloproteinase‑1 (MMP1) participates in the metastasis of pancreatic cancer, and its expression can be regulated by endogenous microRNAs (miRs/miRNAs) and exogenous inflammatory factors. Whether miRNAs that potentially modulate MMP1 expression can also attenuate the pro‑metastatic effects of its inducer on pancreatic cancer is yet to be completely elucidated. In the present study, a systematic analysis including in silico and bioinformatics analyses, a luciferase reporter assay and an RNA electrophoretic mobility shift assay (EMSA), were used to investigate the interaction between miRNAs and MMP1 mRNA. In addition, wound‑healing assays, Transwell assays and xenograft nude mouse models were implemented to investigate the antitumor activities exerted by candidate miRNAs. As a result, hsa‑miR‑623 was screened as a candidate miRNA that interacts with the MMP1 transcript, and an inverse correlation between the expression of hsa‑miR‑623 and MMP1 was observed in human pancreatic cancer tissue samples. The EMSA confirmed that hsa‑miR‑623 was able to directly bind to its cognate target within the 3'‑untranslated region of the MMP1 transcript. In addition, transfection of hsa‑miR‑623 mimics into PANC‑1 and BXPC‑3 cell lines markedly inhibited the expression of MMP1 at the mRNA and protein levels, and attenuated IL‑8‑induced MMP1 expression. hsa‑miR‑623 also decreased IL‑8‑induced epithelial‑mesenchymal transition in PANC‑1 and BXPC‑3 cells via the underlying mechanism of inhibition of ERK phosphorylation. Consequently, hsa‑miR‑623 inhibited pancreatic cancer cell migration and invasion in vitro and metastasis in vivo. The results of the present study suggest that hsa‑miR‑623 represents a novel adjuvant therapeutic target to prevent metastasis in pancreatic cancer.