Long noncoding RNAs (lncRNA) play a role in carcinogenesis. However, the function of lncRNAs in human gastric cancer remains largely unknown. In this study, we identified a novel lncRNA, GClnc1, which was upregulated and associated with tumorigenesis, tumor size, metastasis, and poor prognosis in gastric cancer. GClnc1 affected gastric cancer cell proliferation, invasiveness, and metastasis in multiple gastric cancer models. Mechanistically, GClnc1 bound WDR5 (a key component of histone methyltransferase complex) and KAT2A histone acetyltransferase, acted as a modular scaffold of WDR5 and KAT2A complexes, coordinated their localization, specified the histone modification pattern on the target genes, including SOD2, and consequently altered gastric cancer cell biology. Thus, GClnc1 is mechanistically, functionally, and clinically oncogenic in gastric cancer. Targeting GClnc1 and its pathway may be meaningful for treating patients with gastric cancer. Significance: This report documents a novel lncRNA, GClnc1, which may act as a scaffold to recruit the WDR5 and KAT2A complex and modify the transcription of target genes. This study reveals that GClnc1 is an oncogenic lncRNA in human gastric cancer. Cancer Discov; 6(7); 784–801. ©2016 AACR. This article is highlighted in the In This Issue feature, p. 681

Purpose: Pancreatic ductal adenocarcinoma (PDA) resists immunotherapy of adoptive cell transfer (ACT) and immune checkpoint inhibitors. Understanding the mechanisms underlying this resistance will improve PDA immunotherapy. This study investigated therapeutic effects and underlying mechanisms of anticoagulants on immunotherapy in PDA. Experimental Design: The antitumor activity of immunotherapy was evaluated in mouse models of desert, excluded, and inflamed tumors. The underlying mechanisms were investigated by analyzing immune cell infiltration by immunofluorescence imaging and tumor microcirculation by interstitial fluid pressure and coagulation status measurement. Results: Combined use of heparin and ACT inhibited tumor growth and metastasis, whereas neither heparin nor ACT had any therapeutic effect. The combination of heparin and ACT significantly increased the intratumor infiltration of CD8+ T cells and M1 macrophages and reduced the infiltration of immunosuppressive M2 macrophages and FOXP3+/CD4+ regulatory T cells (Treg). Assessments of tumor microenvironment revealed that heparin promoted tumor vascular regression and normalized the remaining blood vessels, facilitating the extravasation and perivascular accumulation of activated CD8+ T cells in tumors. Mechanistically, tumor microvessel hemodynamic properties were significantly improved by heparin, which is consistent with its inhibitory effects on tumor angiogenesis. Similarly, the combination of heparin and anti-PD1 also produced a pronounced antitumor activity, whereas neither heparin nor anti-PD1 treatment had appreciable antitumor activity. Conclusions: Combined treatment of heparin and ACT or anti-PD1 produced synergistic antitumor effects, which were at least in part through tumor vascular normalization, hence increased antitumor T-cell responses due to reduced Treg infiltration and increased M1 macrophage polarization. This synergistic combination therapy warrants clinical evaluation. See related commentary by Korc, p. 2348

Background: Immunotherapy, including adoptive cell therapy (ACT) and immune checkpoint inhibitors (ICIs), has a limited effect in most patients with colorectal cancer (CRC), and the efficacy is further limited in patients with liver metastasis. Lack of antitumor lymphocyte infiltration could be a major cause, and there remains an urgent need for more potent and safer therapies for CRC. Methods: In this study, the antitumoral synergism of low molecular weight heparin (LMWH) combined with immunotherapy in the microsatellite stable (MSS) highly aggressive murine model of CRC was fully evaluated. Results: Dual LMWH and ACT objectively mediated the stagnation of tumor growth and inhibition of liver metastasis, neither LMWH nor ACT alone had any antitumoral activity on them. The combination of LMWH and ACT obviously increased the infiltration of intratumor CD8⁺ T cells, as revealed by multiplex immunohistochemistry, purified CD8⁺ T-cell transfer assay, and IVIM in vivo imaging. Mechanistically, evaluation of changes in the tumor microenvironment revealed that LMWH improved tumor vascular normalization and facilitated the trafficking of activated CD8⁺ T cells into tumors. Similarly, LMWH combined with anti-programmed cell death protein 1 (PD-1) therapy provided superior antitumor activity as compared with the single PD-1 blockade in murine CT26 tumor models. Conclusions: LMWH could enhance ACT and ICIs-based immunotherapy by increasing lymphocyte infiltration into tumors, especially cytotoxic CD8⁺ T cells. These results indicate that combining LMWH with an immunotherapy strategy presents a promising and safe approach for CRC treatment, especially in MSS tumors.

Intestinal microbial dysbiosis is associated with various intestinal and extraintestinal disorders. Fecal microbiota transplantation (FMT), a type of fecal bacteriotherapy, is considered an effective therapeutic option for recurrent Clostridium difficile infection (rCDI) and also has important value in other intestinal diseases including irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD). The purpose of this review is to discuss promising therapeutic value in extraintestinal diseases associated with gut microbial dysbiosis, including liver, metabolic, chronic kidney, neuropsychiatric, allergic, autoimmune, and hematological diseases as well as tumors.

Purpose: Stromal fibrosis limits nutritional supply and disarrays metabolism in pancreatic cancer (PDA, pancreatic ductal adenocarcinoma). Understanding of the molecular basis underlying metabolic cues would improve PDA management. The current study determined the interaction between glucose-regulated proteins 78 (GRP78) and hypoxia-inducible factor 1α (HIF-1α) and its mechanistic roles underlying PDA response to oxygen and glucose restrains. Experimental Design: Gene expression and its association with clinicopathologic characteristics of patients with PDA and mouse models were analyzed using IHC. Protein expression and their regulation were measured by Western blot and immunoprecipitation analyses. Protein interactions were determined using gain- and loss-of-function assays and molecular methods, including chromatin immunoprecipitation, co-immunoprecipitation, and dual luciferase reporter. Results: There was concomitant overexpression of both GRP78 and HIF-1α in human and mouse PDA tissues and cells. Glucose deprivation increased the expression of GRP78 and HIF-1α, particularly colocalization in nucleus. Induction of HIF-1α expression by glucose deprivation in PDA cells depended on the expression of and its own interaction with GRP78. Mechanistically, increased expression of both HIF-1α and LDHA under glucose deprivation was caused by the direct binding of GRP78 and HIF-1α protein complexes to the promoters of HIF-1α and LDHA genes and transactivation of their transcriptional activity. Conclusions: Protein complex of GRP78 and HIF-1α directly binds to HIF-1α own promoter and LDHA promoter, enhances the transcription of both HIF-1α and LDHA, whereas glucose deprivation increases GRP78 expression and further enhances HIF-1α and LDHA transcription. Therefore, crosstalk and integration of hypoxia- and hypoglycemia-responsive signaling critically impact PDA metabolic reprogramming and therapeutic resistance.