Ectopic expression of HOXC6 blocks myeloid differentiation and predisposes to malignant transformation

Unlocking Transplant Tolerance with Biomaterials

For patients suffering from organ failure due to injury or autoimmune disease, allogeneic organ transplantation with chronic immunosuppression is considered the god standard in terms of clinical treatment. However, the true "holy grail" of transplant immunology is operational tolerance, in which the recipient exhibits a sustained lack of alloreactivity toward unencountered antigen presented by the donor graft. This outcome is resultant from critical changes to the phenotype and genotype of the immune repertoire predicated by the activation of specific signaling pathways responsive to soluble and mechanosensitive cues. Biomaterials have emerged as a medium for interfacing with and reprogramming these endogenous pathways toward tolerance in precise, minimally invasive, and spatiotemporally defined manners. By viewing seminal and contemporary breakthroughs in transplant tolerance induction through the lens of biomaterials-mediated immunomodulation strategies-which include intrinsic material immunogenicity, the depot effect, graft coatings, induction and delivery of tolerogenic immune cells, biomimicry of tolerogenic immune cells, and in situ reprogramming-this review emphasizes the stunning diversity of approaches in the field and spotlights exciting future directions for research to come.

Two Receptors, Two Isoforms, Two Cancers: Comprehensive Analysis of KIT and TrkA Expression in Neuroblastoma and Acute Myeloid Leukemia

Pediatric cancers represent a wide variety of different tumors, though they have unique features that distinguish them from adult cancers. Receptor tyrosine kinases KIT and TrkA functions in AML and NB, respectively, are well-characterized. Though expression of these receptors is found in both tumors, little is known about KIT function in NB and TrkA in AML. By combining gene enrichment analysis with multidimensional scaling we showed that pediatric AMLs with t(8;21) or inv16 and high KIT expression levels stand out from other AML subtypes as they share prominent transcriptomic features exclusively with KIT-overexpressing NBs. We showed that AML cell lines had a predominant expression of an alternative TrkAIII isoform, which reportedly has oncogenic features, while NB cell lines had dominating TrkAI-II isoforms. NB cells, on the other hand, had an abnormal ratio of KIT isoforms as opposed to AML cells. Both SCF and NGF exerted protective action against doxorubicin and cytarabine for t(8;21) AML and NB cells. We identified several gene sets both unique and common for pediatric AML and NB, and this expression is associated with KIT or TrkA levels. NMU, DUSP4, RET, SUSD5, NOS1, and GABRA5 genes are differentially expressed in NBs with high KIT expression and are associated with poor survival in NB. We identified HOXA10, BAG3, and MARCKS genes that are connected with TrkA expression and are marker genes of poor outcome in AML. We also report that SLC18A2, PLXNC1, and MRPL33 gene expression is associated with TrkA or KIT expression levels in both AML and NB, and these genes have a prognostic value for both cancers. Thus, we have provided a comprehensive characterization of TrkA and KIT expression along with the oncogenic signatures of these genes across two pediatric tumors.

Hit-and-run programming of therapeutic cytoreagents using mRNA nanocarriers

Therapies based on immune cells have been applied for diseases ranging from cancer to diabetes. However, the viral and electroporation methods used to create cytoreagents are complex and expensive. Consequently, we develop targeted mRNA nanocarriers that are simply mixed with cells to reprogram them via transient expression. Here, we describe three examples to establish that the approach is simple and generalizable. First, we demonstrate that nanocarriers delivering mRNA encoding a genome-editing agent can efficiently knock-out selected genes in anti-cancer T-cells. Second, we imprint a long-lived phenotype exhibiting improved antitumor activities into T-cells by transfecting them with mRNAs that encode a key transcription factor of memory formation. Third, we show how mRNA nanocarriers can program hematopoietic stem cells with improved self-renewal properties. The simplicity of the approach contrasts with the complex protocols currently used to program therapeutic cells, so our methods will likely facilitate manufacturing of cytoreagents.Current widely used viral and electroporation methods for creating therapeutic cell-based products are complex and expensive. Here, the authors develop targeted mRNA nanocarriers that can transiently program gene expression by simply mixing them with cells, to improve their therapeutic potential.

HOXC6 promotes gastric cancer cell invasion by upregulating the expression of MMP9

Previous studies have demonstrated that the homoebox C6 (HOXC6) gene is highly expressed in gastric cancer tissues and is associated with the depth of tumor invasion, and is associated with poor prognosis of gastric cancer patients expressing HOXC6. The present study investigated the effect and underlying mechanism of HOXC6 on the proliferation and metastasis of gastric cancer cells in vitro. Reverse transcription‑quantitative polymerase chain (PCR) reaction was used to investigate the expression levels of HOXC6 in different gastric cancer cell lines and the effect of different levels of expression on the proliferation of gastric cancer cells was determined by cell growth curve and plate colony formation. The effect of HOXC6 on the anchorage‑independent proliferation of gastric cancer cells was determined by soft agar colony formation assay while the Transwell invasion assay was used to investigate the effect of different levels of HOXC6 expression on the invasive and metastatic abilities of gastric cancer cells. Semi‑quantitative PCR was used to detect the effect of different levels of HOXC6 expression on the expression of matrix metalloproteinase (MMP)2 and MMP9 in gastric cancer cells. Immunoblotting was used to assess MMP9 signaling in the gastric cancer cells. The HOXC6 gene is highly expressed in the majority of the gastric cancer cell lines. Overexpression of HOXC6 promoted gastric cancer cell proliferation and colony formation ability while HOXC6 downregulation inhibited cell proliferation and clone forming ability. HOXC6 overexpression also enhanced the soft agar colony formation ability of gastric cancer cells while HOXC6 downregulation decreased the colony formation ability. Upregulated HOXC6 increased the migration and invasion abilities of gastric cancer cells while interfering with HOXC6 expression inhibited the migration and invasion of the gastric cancer cells. The expression of MMP9 was enhanced with an upregulation of HOXC6 expression while HOXC6 downregulation lowered MMP9 gene expression levels. Increased expression of HOXC6 in gastric cancer cell lines significantly activated extracellular signal‑regulated kinase signaling and upregulated MMP9. The HOXC6 gene promotes the proliferation of gastric cancer cells while upregulation of MMP9 promotes migration and invasion of gastric cancer cells.