Glycan-Lectin interactions between platelets and tumor cells drive hematogenous metastasis.

Glycosylation is a ubiquitous cellular or microenvironment-specific post-translational modification that occurs on the surface of normal cells and tumor cells. Tumor cell-associated glycosylation is involved in hematogenous metastasis. A wide variety of tumors undergo aberrant glycosylation to interact with platelets. As platelets have many opportunities to engage circulating tumor cells, they represent an important avenue into understanding the role glycosylation plays in tumor metastasis. Platelet involvement in tumor metastasis is evidenced by observations that platelets protect tumor cells from damaging shear forces and immune system attack, aid metastasis through the endothelium at specific sites, and facilitate tumor survival and colonization. During platelet-tumor-cell interactions, many opportunities for glycan-ligand binding emerge. This review integrates the latest information about glycans, their ligands, and how they mediate platelet-tumor interactions. We also discuss adaptive changes that tumors undergo upon glycan-lectin binding and the impact glycans have on targeted therapeutic strategies for treating tumors in clinical settings.

Tumor hematogenous metastasis is a serious threat to the survival and prognosis of patients, and a variety of factors help this process to occur, and platelets are also involved. During tumor cell metastasis, platelets can adhere to each other and tumor cells, a phenomenon that leads to the immunity of tumor cells from various threats in metastasis, including immune attacks, shearing forces, etc. Scientists have shown that the adhesion effect between platelets and tumor cells is often dependent on various types of sugars, which are not the sugars we ingest. These sugars often appear as glycosylation modifications on the proteins of the cells, including normal glycosylation modifications and some abnormal structures that only appear on tumor cells, and their ligands, lectins, are also present on the surface of the tumor cells or platelets. Their combination results in the better adaptation of tumor cells to the metastatic process, where proteins such as P-selectin, CLEC-2, and Galectins have been more studied. Focusing on Glycan-Lectin interactions between platelets and tumor cells, related studies help us to further understand tumor metastasis, and intervene in this binding and develop related drugs with great potential.

ANGPTL4 negatively regulates the progression of osteosarcoma by remodeling branched-chain amino acid metabolism.

Angiopoietin-like-4 (ANGPTL4), a secreted glycoprotein that is mainly known as a regulator in lipid metabolism, now, is also indicated to be involved in the regulation of cancer progression and metastasis. However, little is known about not only biological functions, but also underlying mechanism of ANGPTL4 in the progression of osteosarcoma (OS). Here, we discovered that ANGPTL4 is downregulated in OS, and is associated with branched-chain amino acid (BCAA) metabolism. The BCAAs (valine, leucine, and isoleucine) are essential amino acids that play an important role in metabolic regulation. Aberrant BCAA metabolism is also found in various cancers and is associated with tumor progression, including proliferation, invasion, and metastasis. In this study, we indicated that the negative relation between the expression of ANGPTL4 and BCAA catabolism in OS samples and cell lines. The knockdown of ANGPTL4 in OS cells resulted in the accumulation of BCAAs, which in turn activated the mTOR signaling pathway, enhancing OS cell proliferation. Thus, reduced expression of ANGPTL4 is associated with the progression of OS. Taken together, our results demonstrated that the ANGPTL4/BCAA/mTOR axis is an important pathway in OS progression and may be a potential therapeutic target to slow OS progression.

The blood pressure and use of tourniquet are related to local recurrence after intralesional curettage of primary benign bone tumors: a retrospective and hypothesis-generating study.

AIMS: Intralesional curettage is a commonly used treatment for primary bone tumors. However, local recurrence of tumors after curettage remains a major challenge. QUESTIONS: (1) Is blood pressure related to local recurrence after intralesional curettage for benign or intermediate bone tumors? (2) What's the impact of tourniquet usage on the risk of recurrence from high blood pressure? METHODS: This retrospective study evaluated patients receiving intralesional curettage for primary bone tumors from January 2011 to January 2015. A total of 411 patients with a minimum five-year follow-up were included for analysis. Demographic and disease-related variables were first assessed in univariable analyses for local recurrence risk. When a yielded p-value was < 0.2, variables were included in multivariable analyses to identify independent risk factors for local recurrence. Patients were then stratified by tourniquet usage (use/non-use), and risk from high blood pressure was evaluated in both subgroups. RESULTS: At an average follow-up of 6.8 ± 1.0 years, 63 of 411 patients (15.3%) experienced local recurrence. In multivariable analyses, local recurrence was associated with age (OR, 0.96; 95% CI, 0.94-0.99; p = 0.005); tumor type; lesion size (> 5 cm: OR, 3.58; 95% CI, 1.38-9.33; p = 0.009); anatomical site (proximal femur: OR, 2.49; 95% CI, 1.21-5.15; p = 0.014; proximal humerus: OR, 3.34; 95% CI, 1.61-6.92; p = 0.001); and preoperative mean arterial pressure (> 110 mmHg: OR, 2.61; 95% CI, 1.20-5.67; P = 0.015). In subgroup analyses, after adjusting for age, tumor type, lesion size, and anatomical site, tourniquet use modified the preoperative mean arterial pressure - recurrence relationship: when tourniquet was not used, preoperative mean arterial pressure predicted local recurrence (95-110 mmHg, 4.13, 1.42-12.03, p = 0.009; > 110 mmHg, 28.06, 5.27-149.30, p < 0.001); when tourniquet was used, preoperative mean arterial pressure was not related to local recurrence (all p values > 0.05). CONCLUSIONS: A high preoperative blood pressure was related to local recurrence after intralesional curettage for primary bone tumors in our study. Tourniquet usage and controlling blood pressure might be beneficial for reducing local recurrence in patients scheduled to receive intralesional curettage for primary bone tumor treatment. LEVEL OF EVIDENCE: Level IV, hypothesis-generating study.

Computerised tomography features of giant cell tumour of the knee are associated with local recurrence after extended curettage.

BACKGROUND: Extended curettage has increasingly become the preferred treatment for giant cell tumour of bone (GCTB), but the high recurrence rate after curettage poses a major challenge for orthopaedic surgeons. Computed tomography (CT) is valuable in the evaluation of GCTB. Our aim was to identify specific features of GCTB around the knee in pre-operative CT images that might have prognostic value for local recurrence. METHODS: We retrospectively analyzed data from 124 patients with primary GCTB around the knee who underwent extended curettage from 2010 through 2019. We collected demographic, clinical, and therapeutic data along with several CT-derived tumour characteristics. CT-derived tumor characteristics included tumour size, the distance between the tumour edge and articular surface (DTA), and destruction of posterior cortical bone (DPC). Akaike information criterion (AIC) was used to select which variables to enter into multivariate logistic regression models and to determine significant factors affecting recurrence. RESULTS: The total recurrence rate was 21.0% (26/124), and the average follow-up time was 69.5 ± 31.2 months (24-127 months). Age, DTA (< 2 mm), and DPC were significantly related to recurrence, as determined by multivariate logistic regression. The C-index of the final model was 0.79 (95% CI: 0.71 to 0.88), representing a good model for predicting recurrence. CONCLUSION: Identifying certain features of GCTB around the knee on CT has prognostic value for patients treated with extended curettage. A three-factor model predicts tumour recurrence well after extended curettage.

Alpha-(1,6)-fucosyltransferase (FUT8) affects the survival strategy of osteosarcoma by remodeling TNF/NF-κB2 signaling.

Glycosylation is an important modification of membrane proteins that results in functional changes in many cellular activities, from cell-cell recognition to regulatory signaling. Fucosyltransferase 8 (FUT8) is the sole enzyme responsible for core fucosylation, and aberrant fucosylation by dysregulated expression of fucosyltransferases is responsible for the growth of various types of carcinomas. However, the function of FUT8 in the progress of osteosarcoma (OS) has not been reported. In this study, we found that FUT8 is expressed at lower levels in patients with OS and in human OS cell lines such as MNNG/HOS, U2OS, and 143B, suggesting that attenuated expression of FUT8 is involved in the growth and progression of OS. Mechanistically, FUT8 affects the survival strategy of OS by modifying core-fucosylation levels of TNF receptors (TNFRs). Lower fucosylation of TNFRs activates the non-canonical NF-κB signaling pathway, and in turn, decreases mitochondria-dependent apoptosis in OS cells. Together, our results point to FUT8 being a negative regulator of OS that enhances OS-cell apoptosis and suggests a novel therapeutic strategy for treating OS.

Preoperative CT for prediction of local recurrence after curettage of giant cell tumor of bone.

•Preoperative CT images of GCTBs have value in prognostic prediction.•Certain features of GCTBs on CT images are related to local recurrence.•Our models' predictions for GCTB patients accepting extensive curettage are good.

The "sugar-coated bullets" of cancer: Tumor-derived exosome surface glycosylation from basic knowledge to applications.

Scientific interest in exosomes has exploded in recent decades. In 1990 only three articles were published on exosomes, while over 1,700 have already been published half-way into 2020.1 While researchers have shown much interest in exosomes since being discovered in 1981, an appreciation of the potential role of glycans in exosome structure and function has emerged only recently. Glycosylation is one of the most common post-translational modification, which functions in many physiological and pathological aspects of cellular function. Many components of exosomes are heavily glycosylated including proteins, lipids, among others. Thus, glycosylation undoubtedly has a great impact on exosome biosynthesis and function. Despite the importance of glycosylation in exosomes and the recent recognition of them as biomarkers for not only malignancies but also other system dysfunction and disease, the characterization of exosome glycans remains understudied. In this review, we discuss glycosylation patterns of exosomes derived from various tissues, their biological features, and potential for various clinical applications. We highlight state-of-the-art knowledge about the fine structure of exosomes, which will allow researchers to reconstruct them by surface modification. These efforts will likely lead to novel disease-related biomarker discovery, purification tagging, and targeted drug transfer for clinical applications in the future.