Endovascular treatment of aorto-iliac occlusive disease with TASC II C and D lesions: 10 year's experience of clinical technique.

OBJECTIVES: The purpose of this study was to evaluate the therapeutic efficacy and safety of endovascular treatment aorto-iliac occlusive disease (AIOD) with TransAtlantic Inter-Society Consensus II (TASC II) C and D lesions. In addition, 10 years of experience with interventional procedures and treatment options in our center were also worthy of further discussion. METHODS: Between January 2011 and December 2020, a total of 26 consecutive AIOD patients with TASC-II C and D lesions treated endovascular approach were enrolled in this study. Patients' demographic and clinical data were collected, and the safety and efficacy of endovascular therapy were evaluated. In addition, operation procedures were also described. RESULTS: The mean age of patients was 62.2 ± 7 years (49-57 years), and the mean body mass index of patients was 24.2 ± 2.6 kg/m2. Fifteen patients (57.7%) were Rutherford 4, 5 each (19.2%) were Rutherford 3 and 5, and 1 (3.8%) was Rutherford 2. No other serious complications occurred except death in 3 patients. Most of the patients (73.1%) had a history of smoking, and hypertension and hyperlipidemia were common comorbidities. Endovascular therapy was successfully performed in 25 patients, and the technical success rate was 96.2%. The patient's ankle-brachial index improved significantly postoperatively compared with preoperatively (preoperative 0.33 ± 0.14 vs 1.0 ± 0.09, P < 0.001). The primary patency rates were 100%, 95.7%, and 91.3% at 1, 3, and 5 years, while the secondary patency rates were 100%. No treatment-related deaths or serious complications occurred. CONCLUSIONS: Endovascular treatment of AIOD patients with TASC-II C and D lesions might be safe and have a high rate of middle-term and long-term primary patency.

Sialylation Inhibition Can Partially Revert Acquired Resistance to Enzalutamide in Prostate Cancer Cells.

Prostate cancer is a lethal solid malignancy and a leading cause of cancer-related deaths in males worldwide. Treatments, including radical prostatectomy, radiotherapy, and hormone therapy, are available and have improved patient survival; however, recurrence remains a huge clinical challenge. Enzalutamide is a second-generation androgen receptor antagonist that is used to treat castrate-resistant prostate cancer. Among patients who initially respond to enzalutamide, virtually all acquire secondary resistance, and an improved understanding of the mechanisms involved is urgently needed. Aberrant glycosylation, and, in particular, alterations to sialylated glycans, have been reported as mediators of therapy resistance in cancer, but a link between tumour-associated glycans and resistance to therapy in prostate cancer has not yet been investigated. Here, using cell line models, we show that prostate cancer cells with acquired resistance to enzalutamide therapy have an upregulation of the sialyltransferase ST6 beta-galactoside alpha-2,6-sialyltransferase 1 (ST6GAL1) and increased levels of α2,6-sialylated N-glycans. Furthermore, using the sialyltransferase inhibitor P-SiaFNEtoc, we discover that acquired resistance to enzalutamide can be partially reversed by combining enzalutamide therapy with sialic acid blockade. Our findings identify a potential role for ST6GAL1-mediated aberrant sialylation in acquired resistance to enzalutamide therapy for prostate cancer and suggest that sialic acid blockade in combination with enzalutamide may represent a novel therapeutic approach in patients with advanced disease. Our study also highlights the potential to bridge the fields of cancer biology and glycobiology to develop novel combination therapies for prostate cancer.

Sialic acid blockade inhibits the metastatic spread of prostate cancer to bone.

BACKGROUND: Bone metastasis is a common consequence of advanced prostate cancer. Bisphosphonates can be used to manage symptoms, but there are currently no curative treatments available. Altered tumour cell glycosylation is a hallmark of cancer and is an important driver of a malignant phenotype. In prostate cancer, the sialyltransferase ST6GAL1 is upregulated, and studies show ST6GAL1-mediated aberrant sialylation of N-glycans promotes prostate tumour growth and disease progression. METHODS: Here, we monitor ST6GAL1 in tumour and serum samples from men with aggressive prostate cancer and using in vitro and in vivo models we investigate the role of ST6GAL1 in prostate cancer bone metastasis. FINDINGS: ST6GAL1 is upregulated in patients with prostate cancer with tumours that have spread to the bone and can promote prostate cancer bone metastasis in vivo. The mechanisms involved are multi-faceted and involve modification of the pre-metastatic niche towards bone resorption to promote the vicious cycle, promoting the development of M2 like macrophages, and the regulation of immunosuppressive sialoglycans. Furthermore, using syngeneic mouse models, we show that inhibiting sialylation can block the spread of prostate tumours to bone. INTERPRETATION: Our study identifies an important role for ST6GAL1 and α2-6 sialylated N-glycans in prostate cancer bone metastasis, provides proof-of-concept data to show that inhibiting sialylation can suppress the spread of prostate tumours to bone, and highlights sialic acid blockade as an exciting new strategy to develop new therapies for patients with advanced prostate cancer. FUNDING: Prostate Cancer Research and the Mark Foundation For Cancer Research, the Medical Research Council and Prostate Cancer UK.