Prevalence, characteristics, evaluation, and management of carotid body tumors: Systematic analysis based on available evidence.

OBJECTIVE: Although carotid body tumors (CBTs) are rare, they attract particular attention because of their propensity for malignant transformation and the high surgical risk. Because data are scarce and as it is difficult to achieve a large sample size, no study has yet comprehensively analyzed the characteristics, management, or operative complications of CBTs. Therefore, we collected and analyzed all currently available information on CBTs and used the pooled data to derive quantitative information on disease characteristics and management. METHODS: We systematically searched PubMed, Embase, the Cochrane Library, and the Web of Science up to December 1, 2022, for studies that investigated the characteristics and management of CBTs. The primary objective was to identify the prevalence of the various characteristics and the incidence of complications. The secondary objective was to compare patients who underwent preoperative embolization (PE) and those who did not (non-PE), as well as to compare patients with different Shamblin grades and those with and without succinate dehydrogenase (SDH) mutations in terms of CBT characteristics and complications. Two reviewers selected studies for inclusion and independently extracted data. All statistical analyses were performed using the standard statistical procedures of Review Manager 5.2 and Stata 12.0. RESULTS: A total of 155 studies with 9291 patients and 9862 tumors were identified. The pooled results indicated that the median age of patients with CBT was 45.72 years, and 65% were female. The proportion of patients with bilateral lesions was 13%. In addition, 16% of patients had relevant family histories, and the proportion of those with SDH gene mutations was 36%. Sixteen percent of patients experienced multiple paragangliomas, and 12% of CBTs had catecholamine function. The incidence of cranial nerve injury (CNI) was 27%, and 14% of patients suffered from permanent CNI. The incidence rates of operative mortality and stroke were both 1%, and 4% of patients developed transient ischemic attacks. Of all CBTs, 6% were malignant or associated with metastases or recurrences. The most common metastatic locations were the lymph nodes (3%) and bone (3%), followed by the lungs (2%). Compared with non-PE, PE reduced the estimated blood loss (standardized mean difference, -0.95; 95% confidence interval [CI], -1.70 to -0.20) and the operation time (standardized mean difference, -0.56; 95% CI, -1.03 to -0.09), but it increased the incidence of stroke (odds ratio, 2.44; 95% CI, 1.04-5.73). Higher Shamblin grade tumors were associated with more operative complications. Patients who were SDH gene mutation-positive were more likely to have a relevant family history and had more symptoms. CONCLUSIONS: CBT was most common in middle-aged females, and early surgical resection was feasible; there was a low incidence of serious operative complications. Routine PE is not recommended because this may increase the incidence of stroke, although PE somewhat reduced the estimated blood loss and operation time. Higher Shamblin grade tumors increased the incidence of operative complications. Patients who were SDH gene mutation-positive had the most relevant family histories and symptoms.

The characteristics of carotid body tumors in high-altitude region: Analysis from a single center.

OBJECTIVES: Though carotid body tumors are rare, increasing attentions have been given because of malignant transformation and high surgical risk. However, at present, the characteristics and etiology still remain unclear. Our study was designed to describe the clinical features of carotid body tumors in our institution and to compare the results with previous reports. METHODS: We retrospectively reviewed carotid body tumor patients diagnosed in our institution from January 2015 to May 2020. The demographics, comorbidities, lesion location, anatomic characteristics, complications, and postoperative outcomes were evaluated. Carotid body tumor measurements were determined from computed tomography, magnetic resonance imaging, and carotid arteriography examination. We described and compared the clinical features of carotid body tumors in our institution and other reports. RESULTS: We totally identified 122 carotid body tumor cases for the present analysis. The mean age was 50.26 years, with the majority being female (82%). The commonest presentation was a painless neck mass (68%). For the distribution of nationality, most patients were the Han nationality (69.7%). The mean altitude of habitat of patients was 2689.4 km; 19.7% patients suffered bilateral lesions. The main blood supply of carotid body tumors was from external carotid artery (54.1%). For patients who received operation, 11 (11.2%) patients experienced cranial nerve injury. The maximal diameter of tumors was 3.99 ± 1.98 cm in male and 3.38 ± 1.36 cm in female. The volume of tumors was 31.49 ± 29.76 cm3 in male and 15.27 ± 13.06 cm3 in female. The distance to base of skull of tumors was 3.39 ± 1.07 cm (3.99 ± 1.98 cm in male vs 3.38 ± 1.36 cm, P < 0.05). Two patients (2.04%) were identified as having malignant carotid body tumor. CONCLUSIONS: Though carotid body tumor had a low morbidity and multitudinous clinicopathologic features, it was apt to middle-aged women and the main blood supply was from external carotid artery. The painless neck mass was the commonest presentation of carotid body tumors. There were significant difference between male and female patients regarding platelet, hemoglobin, distance to base of skull, tumor volume, altitude of habitat, carotid body tumor location, and hypertension.

Enrichment and culture of spermatogonia from cryopreserved adult bovine testis tissue.

Propagation of bovine spermatogonial stem cells (SSCs) from the cryopreserved testicular tissue is essential for the application of SSCs-related techniques. To explore the appropriate conditions for in vitro culture of bovine spermatogonia (containing putative SSCs), Sertoli cell monolayer and serum concentration were set as two main control factors. Morphological examination showed that the intactness and structure of adult bovine testicular tissue were well maintained after cryopreservation. The enriched bovine spermatogonia were large round CD9 and promyelocytic leukemia zinc finger protein (PLZF) positive cells, with high nucleocytoplasmic ratios and multiple types including single, paired-, aligned-cells or grape cluster-like colonies in vitro. In Sertoli cell co-culture system, bovine spermatogonia attached quickly and proliferated obviously faster than those in the system without Sertoli cells. Serum-free media was no good for the attachment and proliferation of bovine spermatogonia. When 2.5%, 5% and 10% fetal bovine serum (FBS) was employed in the media, spermatogonia attached easily and divided quickly to form paired-, chained-cells or grape cluster-like colonies with comparable percentages in all groups. However, the contaminated somatic cells proliferated robustly in groups containing 5% and 10% FBS. Together, bovine spermatognia isolated from cryopreserved adult testis tissue express CD9 and PLZF, can survive and proliferate conspicuously in Sertoli cell co-culture system, and low serum provides an optimal condition for the survival and proliferation of bovine spermatogonia because of avoiding the rapid growth of testis somatic cells.

RNA interference-mediated silencing of UBCH10 gene inhibits colorectal cancer cell growth in vitro and in vivo.

1. UbcH10 is the cancer-related E2 ubiquitin-conjugating enzyme, and its overexpression has been demonstrated in a variety of malignancies. The aim of the present study is to silence UbcH10 gene by RNA interference (RNAi) and to observe its inhibitory effect on the colorectal cancer cell growth in vitro and in vivo. 2. We constructed the expression vector pGPU6/GFP/Neo/UbcH10-RNAi (pUbcH10-RNAi), which contained a UbcH10 short hairpin RNA expression cassette. Then the UbcH10 gene silencing cell lines LoVo/UbcH10-RNAi and HT-29/UbcH10-RNAi were established. Reverse transcription-polymerase chain reaction and western blot analysis were used to evaluate the expression of the UbcH10 gene. Cell Counting Kit-8 was used to assess properties of tumour cell growth in vitro. Flow cytometry was used to detect the effect of pUbcH10-RNAi on the cell cycle of colorectal cancer cells. Furthermore, the anti-tumour effects of pUbcH10-RNAi were evaluated in vivo in a nude mouse xenografts model. 3. Results demonstrated that UbcH10 gene expression was significantly decreased in pUbcH10-RNAi treated cells. Colorectal cancer cells growth was markedly suppressed in the pUbcH10-RNAi group compared with control conditions and colorectal cancer cells were arrested in the G2-M phase. In vivo, the downregulation of UbcH10 gene expression by pUbcH10-RNAi also inhibited tumour growth in a nude mice xenograft model. 4. Our study suggests that RNA interference-mediated silencing of UbcH10 gene has anti-tumour activity on colorectal cancer and might have therapeutic potential for the treatment of colorectal cancer.