[Study on the application value of fecal SDC2 gene methylation detection in colorectal cancer screening of urban residents in Zengcheng District in Guangzhou City].

Objective: To investigate the application value of fecal Syndecan-2 (SDC2) gene methylated SDC2 (mSDC2) detection in colorectal cancer (CRC) screening among urban residents in Guangzhou City. Methods: A cross-sectional study was conducted in Shitan Town, Zengcheng District, Guangzhou City from July to December 2022. A community-based screening program for CRC was conducted among residents aged 40-74 years old. mSDC2 detection was employed in the participants, and those with positive results should be recommended to receive colonoscopy examination. The positive rate of mSDC2 detection, colonoscopy compliance rate, detection rate of intestinal lesions and clinicopathological characteristics were observed. The relationship between cycle threshold (CT) value of mSDC2 and intestinal lesions was explored. Further, the cost-effectiveness of screening was evaluated. Results: A total of 8 189 fecal samples were collected from 8 877 participants with the recovery rate of 92.25%. 8 048 qualified samples were enrolled in this study, consisted of 3 182 males (39.54%) and 4 866 females (60.46%), with the average age of 56 years old (40-74 years). The positive rate of mSDC2 detection was 7.99% (643/8 048), and the compliance rate of colonoscopy was 73.10% (470/643). 20 cases (4.25%) of colorectal cancer, 109 cases (23.19%) of advanced adenoma, 145 cases (30.85%) of non-advanced adenoma, 79 cases (16.81%) of polyps were detected. The detection rate of intestinal lesions was 75.11% and indicated significant differences in gender and age. 20 CRCs included 15 of stage 0-I, 4 of stage Ⅱ-Ⅲ and 1 of unknown stage. The CT value of mSDC2 was negatively correlated with the proportion of advanced colorectal neoplasms (χ2=16.063, P<0.001). The total cost of the screening was 4.339 5 million yuan, the screening benefit was 28.506 2 million yuan, and the benefit-cost ratio was 6.57. Conclusion: The CRC screening strategy of fecal mSDC2 detection combined with colonoscopy has high colonoscopy compliance and detection rate of intestinal lesions, which is conducive to the detection of early CRCs, and has good cost-effectiveness. This study suggests that this method may be applied to the general CRC screening in China and contribute to the prevention of CRC. The CT value of mSDC2 may have a certain suggestion on the malignant degree of intestinal tumors.

[Validation and modification of AJCC 8th edition staging system for hepatocellular carcinoma--analysis based on SEER database].

Objective: To assess the accuracy of the American Joint Committee on Cancer (AJCC) 8th edition staging system for hepatocellular carcinoma (HCC) and to make an appropriate modification. Methods: Data of patients diagnosed with HCC who underwent surgery were extracted from 2004 to 2015 within the SEER database. Overall survival (OS) and disease-specific survival (DSS) of patients were analyzed. Results: A total of 7 911 patients were included and there were 2 117 females and 5 794 males. The male-to-female ratio was 1.00: 0.36. There were 4 050 patients older than 60 years old. Tumor size ranged from 24 to 65 mm. Tumors with single lobes (80.8%) or single lesions (62.8%) were more common. There were 230 cases and 2 052 cases received radiotherapy and chemotherapy, accounting for 2.9% and 25.9%, respectively. The median follow-up was 42 months. Analysis of the 8th edition of AJCC staging system showed that the survival curves of ⅣA stage and ⅢA stage intersected in both OS and DSS, and the differences were not statistically significant between them (both P>0.05). Analysis of patients in subgroup of ⅣA stage showed that there was no statistically significant difference in the four groups of T1N1M0/T2N0M0, T2N1M0/T3N0M0, T3N1M0/T4N0-1M0 and T3N1M0/T1-4N0-1M1 (all P>0.05). Therefore, the modified 8th edition of the AJCC staging system was proposed after retaining the definition of T/N/M in the old edition: ⅠA and ⅠB stages were retained; ⅣA stage was split: T1N1M0 was included in Ⅱ stage, T2N1M0 in Ⅲ stage, and Ⅳ stage included T3N1M0, T4N0-1M0 and T1-4N0-1M1. Cox proportional risk regression analysis of the modified 8th edition of the AJCC staging showed that significant differences were observed among the four groups, with ⅠB/ⅠA (HR=1.462, 95%CI:1.294-1.651), Ⅱ/ⅠB (HR=1.091, 95%CI:1.003-1.186), Ⅲ/Ⅱ (HR=2.034, 95%CI: 1.793-2.307) and Ⅲ/Ⅳ (HR=1.374, 95%CI: 1.192-1.583) for OS, respectively. The similar findings were seen in DSS, with ⅠB/ⅠA (HR=2.007, 95%CI:1.671-2.411), Ⅱ/ⅠB (HR=1.140, 95%CI:1.023-1.271), Ⅲ/Ⅱ (HR=2.344, 95%CI: 2.018-2.724) and Ⅲ/Ⅳ (HR=1.391, 95%CI:1.180-1.639), respectively. Conclusion: The modified AJCC 8th edition staging system could predict the survival outcome of HCC more accurately.

[Synthesis and antineoplastic activity of N,N'-disubstituted phenyl-3,6-dimethyl-1,4-dihydro-1,2,4,5-tetrazine-1,4-dicarboamide derivatives].

AIM: To search for antineoplastic drugs with fewer side effects and improved activities, using tetrazine derivatives with different substituted groups in their phenyl rings. METHODS: The title compounds have been synthesized by reacting 3,6-dimethyl-1,6-dihydro-1,2,4,5-tetrazine with substituted phenyl isocyanates in the presence of p-dimethylamino pyridine as catalyst. RESULTS: Eighteen new N,N'-disubstituted phenyl-3,6-dimethyl-1,4-dihydro-1,2,4,5-tetrazine-1,4-dicarboamides have been synthesized. Their structures have been confirmed by IR, 1HNMR and elemental analysis. The antineoplastic activities were screened. The structure-activity relationship has also been studied. CONCLUSION: The meta-substituted tetrazine derivatives showed marked antitumor activities against P388 and A-549 when electronic effect constants and hydrophobic constants of their substitutents are in a certain range.