Novel roles of LSECtin in gastric cancer cell adhesion, migration, invasion, and lymphatic metastasis

PFKFB3 facilitates cell proliferation and migration in anaplastic thyroid carcinoma via the WNT/β-catenin signaling pathway

PURPOSE

Despite the involvement of 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase3 (PFKFB3) in the proliferation and metastasis of diverse tumor types, its biological functions and related molecular mechanisms in anaplastic thyroid carcinoma (ATC) remain largely unclear.

METHODS

Datasets from the Gene Expression Omnibus, the Cancer Genome Atlas and immunohistochemistry (IHC) analyses were employed to measure the expression level of PFKFB3 in ATC. A series of assays were performed to analyze the role of PFKFB3 and its inhibitor KAN0438757 in ATC cell proliferation and migration. Furthermore, Western blotting (WB), IHC and luciferase reporter assay were conducted to investigate the potential mechanisms underlying the involvement of PFKFB3 and KAN0438757 in ATC. Additionally, we established a subcutaneous xenograft tumor model in nude mice to evaluate the in vivo tumor growth.

RESULTS

PFKFB3 exhibited a significant increase in its expression level in ATC tissues. The overexpression of PFKFB3 resulted in the stimulation of ATC cell proliferation and migration. Furthermore, this overexpression was associated with the elevated expression levels of p-AKT (ser473), p-GSK3α/β (ser21/9), nuclear β-catenin, fibronectin1 (FN1), matrix metallopeptidase 9 (MMP-9) and cyclin D1. It also promoted the nuclear translocation of β-catenin and the transcription of downstream molecules. Conversely, contrasting results were observed with the downregulation or KAN0438757-mediated inhibition of PFKFB3 in ATC cells. The selective AKT inhibitor MK2206 was noted to reverse the increased expression of p-AKT (ser473) and p-GSK3α/β (ser21/9) induced by PFKFB3 overexpression. The level of lactate was increased in PFKFB3-overexpressing ATC cells, while the presence of KAN0438757 inhibited lactate production. Moreover, the simultaneous use of PFKFB3 downregulation and KAN0438757 was found to suppress subcutaneous tumor growth in vivo.

CONCLUSION

PFKFB3 can enhance ATC cell proliferation and migration via the WNT/β-catenin signaling pathway and plays a crucial role in the regulation of aerobic glycolysis in ATC cells.

Killer instincts: natural killer cells as multifactorial cancer immunotherapy

Natural killer (NK) cells integrate heterogeneous signals for activation and inhibition using germline-encoded receptors. These receptors are stochastically co-expressed, and their concurrent engagement and signaling can adjust the sensitivity of individual cells to putative targets. Against cancers, which mutate and evolve under therapeutic and immunologic pressure, the diversity for recognition provided by NK cells may be key to comprehensive cancer control. NK cells are already being trialled as adoptive cell therapy and targets for immunotherapeutic agents. However, strategies to leverage their naturally occurring diversity and agility have not yet been developed. In this review, we discuss the receptors and signaling pathways through which signals for activation or inhibition are generated in NK cells, focusing on their roles in cancer and potential as targets for immunotherapies. Finally, we consider the impacts of receptor co-expression and the potential to engage multiple pathways of NK cell reactivity to maximize the scope and strength of antitumor activities.

Targeted nanodelivery of siRNA against KRAS G12D inhibits pancreatic cancer

Pancreatic cancer (PC) stands as a most deadly malignancy due to few effective treatments in the clinics. KRAS G12D mutation is a major driver for most PC cases, and silencing of KRAS G12D is considered as a potential therapeutic strategy for PC, which is nevertheless crippled by lacking a pragmatic delivery system for siRNA against KRAS G12D (siKRAS). Here, we report that cRGD peptide-modified bioresponsive chimaeric polymersomes (cRGD-BCP) mediate highly efficient siKRAS delivery to PANC-1 tumor, potently silencing KRAS G12D mRNA in tumor cells and effectively suppressing PC tumor growth in mice. cRGD-BCP exhibited remarkable encapsulation of siKRAS (loading content > 14 wt.%, loading efficiency > 90%) to form stable and uniform (ca. 68 nm) nanovesicles (cRGD-BCP-siKRAS). Of note, cRGD density greatly impacted the cellular uptake and silencing efficiency of cRGD-BCP-siKRAS in PANC-1 cells, in which an optimal cRGD density of 15.7 mol.% achieved 3.7- and 3.6-fold enhancement of internalization and gene silencing, respectively, compared with non-targeted BCP-siKRAS. cRGD-BCP-siKRAS was practically intact after 3-week storage at 4°C. Intriguingly, cRGD-BCP-siKRAS markedly enhanced the uptake of siKRAS in PANC-1 tumor, and at a siKRAS dose of 3 mg/kg knocked down 90% KRAS G12D gene, resulting in potent tumor inhibition and extraordinary survival benefits (median survival time: 101 days versus 38 (PBS group) and 59 days (BCP-siKRAS)) with 40% mice achieved complete regression. It appears that cRGD-mediated nanodelivery of siKRAS provides a potential cure for pancreatic cancer. STATEMENT OF SIGNIFICANCE: Small interfering RNA (siRNA) emerges as a specific and powerful biopharmaceuticals against cancers; however, inefficient in vivo delivery impedes its clinical translation. In spite of the fact that KRAS G12D mutation has been identified as a major driver for most pancreatic cancer, its notorious non-druggability renders little success on development of molecular targeted drugs. Pancreatic cancer is deemed as current king-of-cancer. Here, we show that cyclic RGD peptide installed bioresponsive polymersomes are able to efficiently deliver siRNA against KRAS G12D to pancreatic tumor, resulting in 90% gene knock-down and effective tumor inhibition. Strikingly, two out of five mice have been cured. This targeted nanodelivery of siRNA provides a high-efficacy treatment strategy for pancreatic cancer.