Peptidase inhibitor 16 promotes proliferation of pancreatic ductal adenocarcinoma cells through OASL signaling.

Pancreatic ductal adenocarcinoma (PDAC) is a highly invasive cancer with a poor prognosis and a 5-year survival rate of less than 11%. As a member of the CAP superfamily of proteins, the role of peptidase inhibitor 16 (Pi16) in tumor progression is still unclear. Immunohistochemistry and quantitative RT-PCR methods were used to detect the expression levels of Pi16 protein and mRNA in PDAC patients. CRISPR/Cas9 technology was used to knock out the expression of Pi16 in PDAC cell lines. In vivo and in vitro experiments were used to verify the effect of Pi16 on PDAC proliferation ability. By RNA sequencing, we found that oligoadenylate synthetase L (OASL) can serve as a potential downstream target of Pi16. The expression of Pi16 was higher in PDAC tissues than in matched adjacent tissues. High expression of Pi16 was associated with PDAC progression and poor prognosis. Overexpression of Pi16 could promote the proliferation of PDAC cells in vitro and in vivo. Bioinformatics analysis and coimmunoprecipitation assays showed that Pi16 could bind to OASL. Moreover, the functional recovery test confirmed that Pi16 could promote the proliferation of PDAC via OASL. Our present study demonstrates that Pi16 might participate in the occurrence and development of PDAC by regulating cell proliferation by binding to OASL, indicating that Pi16 might be a promising novel therapeutic target for PDAC.

Anesthetic management of bilateral pheochromocytoma resection in Von Hippel-Lindau syndrome: A case report.

BACKGROUND: Von Hippel-Lindau disease (also known as VHL syndrome), is an autosomal dominant inherited disease. We describe a sporadic case of VHL syndrome where bilateral pheochromocytomas were unexpectedly identified. The patient underwent selective laparoscopic resections of the pheochromocytomas, and the anesthetic management during surgery was complex and challenging. CASE SUMMARY: A 22-year-old man presented to our hospital to seek medical advice for infertility without any other complaints. The results of computed tomography and catecholamine levels in blood and urine demonstrated adrenal gland masses which were diagnosed as pheochromocytomas. Further examination confirmed that the patient also had VHL syndrome. After thorough preparation, the patient underwent selective laparoscopic resection of the pheochromocytomas and was discharged 10 d after surgery. We describe the process of perioperative anesthesia management in this patient undergoing pheochromocytoma resection. CONCLUSION: This case summaries specific clinical traits and considerations in perioperative anesthesia management for VHL syndrome patients undergoing bilateral pheochromocytoma resection.

Norepinephrine can act via alpha(2)-adrenoceptors to reduce the hyper-excitability of spinal dorsal horn neurons following chronic nerve injury.

BACKGROUND/PURPOSE: Rats display behavioral signs of neuropathic pain lasting for months in the chronic constriction injury (CCI) model. During intrathecal anesthesia, the administered drugs mainly diffuse directly into the superficial neurons in the spinal dorsal horn. This study aimed to investigate the effect of bath application of norepinephrine on whole cell patch clamp recordings from spinal cord slices of CCI rats with allodynia. METHODS: An assessment of paw withdrawal threshold in response to mechanical stimulation was performed on the operated side on the day before surgery and was repeated after recovery from anesthesia and on the 7(th) and 14(th) days after surgery. Spinal cord slice preparations containing dorsal horn neurons were obtained from both sham-operated rats and CCI rats (after the 14(th) postoperative day behavior test). RESULTS: Compared with normal controls, CCI rats had significantly lower levels of both hyperpolarization and spike threshold in single action potentials recorded from lamina I and II neurons of the spinal dorsal horn. In contrast, a series of action potential recordings showed that the percentage of spiking neurons of the spinal dorsal horn of CCI rats were significantly higher than those of normal controls. The CCI-induced reduction in hyperpolarization, as well as the increased numbers of spinal dorsal horn spiking neurons could be significantly reduced by norepinephrine application. The norepinephrine-induced increased hyperpolarization and input resistance could be abolished by the application of an alpha(2)-adrenoceptor antagonist (idazoxan; 200 nM). CONCLUSION: The results suggest that chronic nerve injury may induce neuropathic pain by increasing the excitability of spinal dorsal horn neurons. This excitability can be reduced by norepinephrine.