Animal experiments are an essential component of life sciences and medical research. However, the external validity and reliability of individual animal studies are frequently challenged by inherent limitations such as small sample sizes, high design heterogeneity, and poor reproducibility, which impede the effective translation of research findings into clinical practice. Systematic reviews and meta-analysis represent a key methodology for integrating existing evidence and enhancing the robustness of conclusions. Currently, however, the application of systematic reviews and meta-analysis in the field of animal experiments lacks standardized guidelines for their conduct and reporting, resulting in inconsistent quality and, to some extent, diminishing their evidence value. To address this issue, this paper aims to systematically delineate the reporting process for systematic reviews and meta-analysis of animal experiments and to propose a set of standardized recommendations that are both scientific and practical. The article's scope encompasses the entire process, from the preliminary preparatory phase [including formulating the population， intervention， comparison and outcome （PICO） question, assessing feasibility, and protocol pre-registration] to the key writing points for each section of the main report. In the core methods section, the paper elaborates on how to implement literature searches, establish eligibility criteria, perform data extraction, and assess the risk of bias, based on the Preferred Reporting Items for Systematic Reviews and Meta-analysis （PRISMA) statement, in conjunction with relevant guidelines and tools such as Animal Research： Reporting of in Vivo Experiments （ARRIVE) and a risk of bias assessment tool developed by the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE). For the presentation of results, strategies are proposed for clear and transparent display using flow diagrams and tables of characteristics. The discussion section places particular emphasis on how to scientifically interpret pooled effects, thoroughly analyze sources of heterogeneity, evaluate the impact of publication bias, and cautiously discuss the validity and limitations of extrapolating findings from animal studies to clinical settings. Furthermore, this paper recommends adopting the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology to comprehensively grade the quality of evidence. Through a modular analysis of the entire reporting process, this paper aims to provide researchers in the field with a clear and practical guide, thereby promoting the standardized development of systematic reviews and meta-analysis of animal experiments and enhancing their application value in scientific decision-making and translational medicine.

Aristolochic acids (AAs) have long been considered as a potent carcinogen due to its nephrotoxicity. Aristolochic acid I (AAI) reacts with DNA to form covalent aristolactam (AL)-DNA adducts, leading to subsequent A to T transversion mutation, commonly referred as AA mutational signature. Previous research inferred that AAs were widely implicated in liver cancer throughout Asia. In this study, we explored whether AAs exposure was the main cause of liver cancer in the context of HBV infection in mainland China. Totally 1256 liver cancer samples were randomly retrieved from 3 medical centers and a refined bioanalytical method was used to detect AAI-DNA adducts. 5.10% of these samples could be identified as AAI positive exposure. Whole genome sequencing suggested 8.41% of 107 liver cancer patients exhibited the dominant AA mutational signature, indicating a relatively low overall AAI exposure rate. In animal models, long-term administration of AAI barely increased liver tumorigenesis in adult mice, opposite from its tumor-inducing role when subjected to infant mice. Furthermore, AAI induced dose-dependent accumulation of AA-DNA adduct in target organs in adult mice, with the most detected in kidney instead of liver. Taken together, our data indicate that AA exposure was not the major threat of liver cancer in adulthood.

Objective:This study aims to reveal the special immune infiltrating environment and possible immune escape mechanism of giant cell tumor of bone through single-cell sequencing data.Methods:The fresh samples obtained from 4 patients with primary giant cell tumor of bone from January 2018 to December 2021 were collected, and single-cell transcriptome sequencing was performed on the 10X platform to explore the characteristics and immune environment of giant cell tumor of bone by using t-distributed stochastic neighbor embedding ( t-SNE). The main cell types and signal pathways of immune cell regulation and function in giant cell tumor of bone were observed by cell communication analysis. Results:Cell clustering, the definition of basic cell types, the classification of immune cells, and the mutual regulatory relationship between cell types were analyzed for 35 643 single-cell data from 4 giant cell tumor samples of bone. It was found that giant cell tumor of bone was composed of 9 basic cell types, in which the immune cells were mainly CD8 + T cells (51%) and the non-immune cells were mainly fibroblast like spindle stromal cells (74%). The immune infiltration of giant cell tumor of bone is dominated by cytotoxic CD8 + T cells and lacks exhausted CD8 + T cells. CD4 + T cells are characterized by high expression of immune checkpoint genes CTLA4 and TIGIT. In giant cell tumor of bone, immune cells mainly act on multinucleated osteoclast like giant cells through PARs and CCL signaling pathways, but not stromal cells. Conclusion:This study defined the main cell types of giant cell tumor of bone through single cell sequencing data, and further revealed the composition characteristics of its immune infiltration, and found that the target of its immune cells was mainly multinuclear osteoclast like giant cells, which provided effective information for further understanding the occurrence and development of giant cell tumor of bone.

Objective:To investigate the effect of 25 hydroxyvitamin D [25 (OH) D] on postoperative parathyroid function in patients with papillary thyroid carcinoma (PTC) .Methods:426 patients who diagnosed as PTC and underwent at least total thyroidectomy plus central lymph node dissection (including lateral lymph node dissection) in Center of Thyroid and Parathyroid Surgery of West China Hospital, Sichuan University, from Jun. 2017 to Sep. 2019 were retrospectively analyzed. Among them, 313 were women and 113 were men, they were divided into vitamin D deficient (VDD) group ( n=297) and normal group ( n=129) according to preoperative 25 (OH) D levels ≤ 20ng/ml and > 20ng/ml. SPSS 23.0 statistical software was used for data processing. Pearson χ2 test or Fisher exact test were used to compare the incidence of clinical hypoparathyroidism, biochemical temporary and biochemical permanent hypoparathyroidism between the two groups. Univariate and multivariate logistic regression analysis were used to analyze the related factors of postoperative hypoparathyroidism between the two groups. Results:Preoperative 25 (OH) D level was significantly correlated with postoperative biochemical temporary hypoparathyroidism ( P=0.04, OR=1.11) . Compared with patients with adequate preoperative vitamin D, preoperative vitamin D deficiency increased the risk of biochemical transient hypoparathyroidism by 6.67 times ( P=0.03;OR=6.67) . There was no significant correlation between preoperative vitamin D deficiency and early postoperative clinical hypoparathyroidism (2.7% vs 3.9%, P=0.55) . Conclusion:Correction of vitamin D deficiency before operation may reduce the incidence of postoperative temporary hypoparathyroidism caused by 25 (OH) D deficiency.

Objective:To investigate the value of the decrease rate of parathyroid hormone (PTH) in predicting permanent hypoparathyroidism (PHP) in one month after operation of papillary thyroid carcinoma (PTC) .Methods:The clinical data of 322 patients with PTC who underwent at least total thyroidectomy and unilateral central lymph node dissection in the Thyroid Surgery Center of West China Hospital of Sichuan University from Jan. 2013 to Jun. 2018 were retrospectively analyzed. There were 257 women and 65 men. According to the time when PTH returned to normal, they were divided into 307 cases in the temporary hypoparathyroidism (THP) group and 15 cases in the PHP group. The decrease rate of PTH and the incidence of hypoparathyroidism in one month after operation were counted, the clinical characteristics and operation information were observed, and the risk factors of PHP were analyzed. SPSS 23.0 statistical software was used for data processing. χ 2 test and t test were used for comparison between THP and PHP. The related factors were analyzed by multivariate logistic regression. Results:307 cases of THP and 15 cases of PHP were included. Multivariate logistic analysis showed that age ≥ 55 years old ( OR, 35.193; 95% CI, 2.936 - 421.870; P=0.005) and PTH before operation closer to normal lower limit ( OR, 2.349; 95% CI, 1.161 - 4.755; P = 0.018) were independent risk factors for PHP. Patients with PHP had a higher rate of PTH decline in 1 month after operation ( OR, 373.439; 95% CI, 26.568 - 5248.983; P=0.000) . The ROC curve showed that the sensitivity and specificity of predicting PHP were 86.7% and 94.8% respectively. Conclusions:The age of patients with PTC ≥ 55 years old and PTH before operation closer to normal lower limit are independent risk factors for the occurrence of PHP. The decline rate of PTH in one month after operation which more than 73.2% can predict PHP.

Objective:To examine the correlation factors of contralateral central lymph node metastasis in unilateral papillary thyroid carcinoma with lateral cervical lymph node metastasis.Methods:The clinical data of patients with unilateral papillary thyroid carcinoma who underwent total thyroidectomy and bilateral central lymph node dissection and ipsilateral cervical lymph node dissection from June 2016 to June 2018 at Department of Thyroid Surgery, West China Hospital, Sichuan University were analyzed retrospectively. A total of 317 patients, including 87 males and 230 females, aged (41.4±12.1) years (range: 16 to 75 years), were enrolled in this study. The risk factors of contralateral central lymph node metastasis were analyzed by χ 2 test and Spearman correlation analysis. Results:There were 116, 69, 269, and 181 cases of pretracheal lymph node, prelaryngeal lymph node, ipsilateral central lymph node and contralateral central lymph node metastasis, respectively, and 16 cases of skipping metastasis. Univariate analysis showed that contralateral central lymph node metastasis was associated with gender, maximum tumor diameter, capsule invasion, pretracheal lymph node metastasis, prelaryngeal lymph node metastasis, and ipsilateral central lymph node metastasis (all P<0.05). Spearman correlation analysis showed that male ( r s=0.162, P=0.004), maximum tumor diameter>10 mm ( r s=0.184, P=0.001), capsule invasion ( r s=0.135, P=0.016), pretracheal lymph node metastasis ( r s=0.394, P<0.01), prelaryngeal lymph node metastasis ( r s=0.272, P<0.01) and ipsilateral central lymph node metastasis ( r s=0.203, P<0.01) were independent correlation factors for contralateral central lymph node metastasis. Conclusion:For patients with unilateral papillary thyroid carcinoma with ipsilateral cervical lymph node metastasis, bilateral central lymph node dissection should be considered if male, tumor diameter>10 mm, capsule invasion, pretracheal lymph node metastasis, prelaryngeal lymph node metastasis, or ipsilateral central lymph node metastasis.

Objective:To examine the correlation factors of contralateral central lymph node metastasis in unilateral papillary thyroid carcinoma with lateral cervical lymph node metastasis.Methods:The clinical data of patients with unilateral papillary thyroid carcinoma who underwent total thyroidectomy and bilateral central lymph node dissection and ipsilateral cervical lymph node dissection from June 2016 to June 2018 at Department of Thyroid Surgery, West China Hospital, Sichuan University were analyzed retrospectively. A total of 317 patients, including 87 males and 230 females, aged (41.4±12.1) years (range: 16 to 75 years), were enrolled in this study. The risk factors of contralateral central lymph node metastasis were analyzed by χ 2 test and Spearman correlation analysis. Results:There were 116, 69, 269, and 181 cases of pretracheal lymph node, prelaryngeal lymph node, ipsilateral central lymph node and contralateral central lymph node metastasis, respectively, and 16 cases of skipping metastasis. Univariate analysis showed that contralateral central lymph node metastasis was associated with gender, maximum tumor diameter, capsule invasion, pretracheal lymph node metastasis, prelaryngeal lymph node metastasis, and ipsilateral central lymph node metastasis (all P<0.05). Spearman correlation analysis showed that male ( r s=0.162, P=0.004), maximum tumor diameter>10 mm ( r s=0.184, P=0.001), capsule invasion ( r s=0.135, P=0.016), pretracheal lymph node metastasis ( r s=0.394, P<0.01), prelaryngeal lymph node metastasis ( r s=0.272, P<0.01) and ipsilateral central lymph node metastasis ( r s=0.203, P<0.01) were independent correlation factors for contralateral central lymph node metastasis. Conclusion:For patients with unilateral papillary thyroid carcinoma with ipsilateral cervical lymph node metastasis, bilateral central lymph node dissection should be considered if male, tumor diameter>10 mm, capsule invasion, pretracheal lymph node metastasis, prelaryngeal lymph node metastasis, or ipsilateral central lymph node metastasis.

Liposarcoma(LPS)is the most common type of soft-tissue sarcoma(STS). The current treatment methods are still based on complete surgical resection. Radiotherapy and chemotherapy as adjuvant treatment or distant metastasis,and the main treat-ment of unresectable liposarcoma have limited efficacy,have not widely recognized. With the extensive and in-depth of LPS molecular targeted therapy,the research achievements in this area are remarkable. Emerging targets for LPS include receptors such as tyrosine ki-nase receptor AXL,fibroblast growth factor receptor(FGFR),insulin-like growth factor-1 receptor(IGF-1R),nuclear export re-ceptor XPO1(Exportin-1),and proteins/enzymes such as heat shock protein 90( Hsp90),bispecific tyrosine( Y) phosphorylation-regulated kinase 1B( DYRK1B) and signal pathways such as SRC/FAK/RHO/ROCK have shown good prospects for anti-LPS in preclinical studies. The research progress in the aspects is summarized as follows.

Objective To investigate the role of glycogen synthase kinase -3beta(GSK3β)on invasion and metastasis of human osteosarcoma cells .Methods Expression and phosphorylation of GSK 3βwere examined in osteosarcoma cell lines and tumor tissue from osteosarcoma patients by Western blot .The effects of small mole-cule GSK3βinhibitors on cell metastasis were detected by cell invasion assay and cell migration assay .Results Osteosarcoma cell lines showed increased GSK 3βexpression and abnormal activity regulation .In tumor tissue of patients with osteosarcoma metastasis and non -metastasis,GSK3βwere detected expression and abnormal activi-ty,especially in tumor tissue of the patients with osteosarcoma metastasis .Inhibition of GSK3βactivity resulted in inhibiting cells invasion and migration in osteosarcoma cell line .Conclusion In this research,we demonstrated that GSK3βencouraged osteosarcoma cells metastasis .The result will open up a potential target for clinical treat-ment of osteosarcoma .

Objective To discuss the related factors of early pathological fracture after curettage of benign bone tumors in femoral shaft.Methods The clinical data of 47 patients with benign bone tumors in femoral shaft,treated by curettage with bone graft via the vastus lateralis approach from March 2004 to March 2011,were retrospectively analyzed.Thirteen patients of them presented with early pathological fracture after the curettage.In fracture group,there were 13 cases,11 males and 2 females,and the time from finishing curettage to fracture occurring ranged from 21 to 36 days.In non-fracture group,there were 34 cases,23 males and 11 females.The following data of fracture group and non-fracture group were compared and analyzed,such as specific value of absolute width of tumor and transverse diameter of bone shaft,specific value of defect width of bone window and sagittal diameter of bone shaft,defect length-width ratio of bone window,defect morphology of bone window,classification of bone tumor,violence of causing injury and compliance to medical advice.Results The average defect length-width ratio of bone window in fracture group was 3.72±3.58,in non-fracture group was 2.67±6.35.For classification of tumor,in fracture group 1 case was in incubation period,6 in active period,6 in invasion period; in non fracture group 21 cases were in incubation period,10 in active period,and 3 in invasion period.Four cases in fracture group had poor compliance to medical advice,and 9 in non-fracture group had good compliance.Between two groups,there were no statistical differences in specific value of absolute width of tumor and transverse diameter of bone shaft,specific value of defect width of bone window and sagittal diameter of bone shaft,and defect morphology of bone window.Conclusion When defect length-width ratio of bone window is larger than 4,the classification of tumor causes expanded incisal edge,and the cortical bone was damaged extensively,there are more possibilities for pathological fracture.