[Internal carotid artery embolization in endoscopic salvage surgery for recurrent nasopharyngeal carcinoma: a single-center retrospective study]

Objective: To evaluate the efficiency of internal carotid artery (ICA) embolization technology in endoscopic salvage surgery for recurrent nasopharyngeal carcinoma (rNPC) invading the ICA. Methods: From January 2016 to March 2021, 83 patients with rNPC who invaded the ICA and underwent endoscopic extended nasopharyngectomy were retrospectively collected from the Eye & ENT Hospital in Fudan University, including 60 males and 23 females. The age of the patients ranged from 27 to 77 years. The standard of ICA invasion was that the distance from the lesion to the ICA on enhanced MRI was ≤ 1.8 mm. The clinical characteristics, ICA management strategy and survival prognosis of patients were analyzed, and the effectiveness of ICA embolization was evaluated. Kaplan-Meier method was used to calculate the survival rate and Log-rank test was used to compare the difference. Results: In 83 patients with rNPC, there were 13 patients with rT2, 38 patients with rT3, 32 patients with rT4, and 16 patients had lymph node metastasis. A total of 37 patients (44.6%) underwent ICA coil embolization before surgery, of which 2 cases underwent external carotid-middle cerebral artery artery bypass grafting and ICA embolization due to positive balloon occlusion test (BOT). Patients with positive surgical margin accounted for 24.1% (20/83). Among them, patients with rT4 and patients without ICA embolization had a higher positive rate of surgical margin (P value was 0.001, 0.043, respectively). The 3-year overall survival (OS) and progression free survival (PFS) rate of all patients was 46.5% and 26.7%, respectively. In addition, the 3-year OS and PFS of patients with ICA embolization was significantly higher than those without ICA embolization, respectively (69.1% vs 27.8%, P=0.003; 33.9% vs 18.9%, P=0.018). Only 2 patients (2/37, 5.4%) had cerebral infarction complications after coil embolization of the affected ICA due to negative BOT. Conclusion: Preoperative ICA embolization can be used to treat patients with rNPC invading the ICA, improve the total removal rate and survival rate of patients, which is an effective salvage treatment.

[The endoscopic transnasal approach in management of the sinonasal tumor invading the anterior skull base]

Objective: To evaluate the feasibility of the endoscopic transnasal approach (ETA) and to analyze the outcomes and factors of this surgical technique in the management of the tumor invading the anterior skull base. Methods: A retrospective analysis was performed on 42 patients (31 males and 11 females, with mean age of 49 years) with sinonasal tumor invading the anterior skull base, who underwent ETA from June 2015 to April 2019 in Eye, Ear, Nose and Throat Hospital of Fudan University. Pathologically, there were 15 cases of squamous carcinoma (14 patients with T4bN0M0 and 1 patient with T4bN1M0) and 27 of olfactory neuroblastomas with Kadish stage C. Anterior skull base reconstruction was performed using the vascular pedicled nasoseptal mucoperiosteal flap and fascia lata. Brain non-contrast-enhanced CT was performed on the first postoperative day to exclude massive pneumocephalus, relevant brain edema and subarachnoid hemorrhage. Sinonasal contrast-enhanced MR was performed to assess the extent of the tumor removal. Kaplan-Meier analysis was used to calculate the overall survival (OS) and Cox multivariate regression analysis was used to determine the prognostic factors. Results: The mean duration of the surgery was 452 minutes. Total resection was performed in 36 patients (85.7%), subtotal resection in 2 patients (4.8%) with orbital involvement, partial resection in one patient (2.4%) with injury of the internal carotid artery. One patient (2.4%) underwent the second resection because of the tumor residual, two patients (4.8%) with unsure tumor residual. Mean follow-up was 20 months, with 17 months of median follow-up. One-, two-and three-year overall survival was 86.5%, 76.9% and 64.5%, respectively. For squamous carcinoma, one-, two-and three-year overall survival was 86.2%, 86.2% and 57.4%, respectively. For olfactory neuroblastomas, One-, two-and three-year overall survival was 86.9%, 75.3% and 67.8%, respectively. Multivariate analysis showed that tumor residual (P=0.001) and recurrence (P<0.01) were independent prognostic factors for survival. Conclusions: The ETA is safe and feasible in selected patients with sinonasal tumor invading the anterior skull base. Tumor residual and recurrence are independent prognostic factors for survival.

Developmental changes in the expression of the GLUT2 and GLUT4 genes in the longissimus dorsi muscle of Yorkshire and Tibetan pigs

Glucose transporter proteins 2 and 4 (GLUT2 and GLUT4) play important roles in glucose transport and energy metabolism. Changes in the levels of GLUT2 and GLUT4 mRNA were measured in longissimus dorsi muscle from the lean Yorkshire and fat Tibetan pig breeds at six different time points (1, 2, 3, 4, 5, and 6 months) with quantitative real-time polymerase chain reactions. The results showed that GLUT2 and GLUT4 mRNA were abundantly expressed in the longissimus dorsi muscle and that the developmental expression patterns were similar in both breeds. Tibetan pigs exhibited higher intramuscular fat and GLUT2 mRNA levels, while Yorkshire pigs exhibited a higher myofiber cross-sectional area (CSA) and GLUT4 mRNA levels. Furthermore, the changes in the GLUT4 mRNA levels were strongly and positively correlated with the CSA over a period of six months. These results exhibit time- and breed-specific expression patterns of GLUT2 and GLUT4, which highlight their potential as candidate genes for assessing adipose deposition and muscle development in pigs. These differences in the expression of GLUT family genes may also have indications for meat quality.

Evaluation of endogenous control genes for gene expression studies across multiple tissues and in the specific sets of fat- and muscle-type samples of the pig

To normalize a set of quantitative real-time PCR (q-PCR) data, it is essential to determine an optimal number/set of housekeeping genes, as the abundance of housekeeping genes can vary across tissues or cells during different developmental stages, or even under certain environmental conditions. In this study, of the 20 commonly used endogenous control genes, 13, 18 and 17 genes exhibited credible stability in 56 different tissues, 10 types of adipose tissue and five types of muscle tissue, respectively. Our analysis clearly showed that three optimal housekeeping genes are adequate for an accurate normalization, which correlated well with the theoretical optimal number (r ≥ 0.94). In terms of economical and experimental feasibility, we recommend the use of the three most stable housekeeping genes for calculating the normalization factor. Based on our results, the three most stable housekeeping genes in all analysed samples (TOP2B, HSPCB and YWHAZ) are recommended for accurate normalization of q-PCR data. We also suggest that two different sets of housekeeping genes are appropriate for 10 types of adipose tissue (the HSPCB, ALDOA and GAPDH genes) and five types of muscle tissue (the TOP2B, HSPCB and YWHAZ genes), respectively. Our report will serve as a valuable reference for other studies aimed at measuring tissue-specific mRNA abundance in porcine samples.