Detection rate of pulmonary nodules by CT scan at different doses and application value of artificial intelligence assistance / 中国医师进修杂志

Objective:To investigate the detection rate of pulmonary nodules (PN) by CT scan at different doses and the application value of artificial intelligence(AI) system assistance.Methods:From October 2019 to October 2021, 210 patients with PN in Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, were retrospectively selected, and they were divided into the study group (106 cases) and the control group (104 cases) by CT scan at different doses. The control group used the conventional average dose (169 mAs) CT scan, the study group used an average low-dose (54 mAs) CT scan. The PN detection rate of different gender, age, body mass index (BMI) between the two groups were compared. The morphological characteristics, radiation dose, CT image quality between the two groups were compared. The diagnostic efficiency of radiologists and AI system was compared.Results:The detection rate of PN in the study group and the control group had no significant difference: 73.58% (78/106) vs. 80.77%(84/104), χ2 = 1.54, P>0.05. The detection rate of PN with different gender, age group and BMI in the two groups had no significant differences ( P>0.05). The diameter of nodules and the rates of calcification, cavitation, bronchial sign, lobar sign, burr sign and pleural adhesion sign in the two groups had no significant differences ( P>0.05). The mean effective tubular bulb dose, length product of radiation dose, total tubular bulb dose, radiation volume dose index in the study group were higher than those in the control group: (46.15 ± 7.38) mAs vs. (104.39 ± 10.53) mAs, (169.24 ± 19.77) mGy·cm vs. (427.17 ± 43.58) mGy·cm, (972.65 ± 58.34) mAs vs. (2 861.26 ± 181.37) mAs, (3.55 ± 1.16) mGy vs. (8.95 ± 2.07) mGy, there were statistical differences ( P<0.05). The excellent, good, acceptable, poor of 1.0 mm image quality in the study group were 26, 60, 18, 2, and in the control group were 32, 64, 8, 0, there was statistical difference ( u =1.71, P = 0.087). The excellent, good, acceptable, poor of maximum intensity projection (MIP) image quality in the study group were 58, 42, 6, 0 and in the control group were 70, 34, 0, 0, there was statistical difference ( u = 1.81, P = 0.070). The detection rate of PN by AI low-dose CT scan was higher than that of radiologists: 88.68%(94/106) vs. 73.58%(78/106), there was statistical difference ( χ2 = 7.89, P = 0.005). Conclusions:The low-dose CT chest scans for PN, the results of detection rate, morphological characteristics, CT image quality are basically the same as those of conventional-dose CT chest scans, and can greatly reduce the radiation dose, which is more suitable for PN screening, and combined with AI system can significantly improve the detection rate of PN.

Abnormal expression and its regulation mechanism of Cav-1 gene in gastric cancer / 临床与实验病理学杂志

Purpose To investigate the expression of Cav-1 in gastric cancer ( GC) cell lines and GC samples, and to analyze the pos-sible effect of gene methylation in expression of Cav-1. Methods Methylation specific PCR ( MSP) method was applied to examine the CpG methylation of the Cav-1 promoter in GC cell lines (AGS, MKN45, BGC-823) and 104 samples of GC and corresponding ad-jacent tissues. RT-PCR method was applied to examine the mRNA expression in GC cell lines. IHC were applied to examine the pro-tein expression of Cav-1 in the GC tissues. Results The expression level of Cav-1 mRNA was obviously increased after treated with 5-aza-2’-deoxycytidine (5-Aza-Dc, a demethylation agent) in AGS cell line. We detected the positive expression of Cav-1 gene in MKN45 and BGC-823 cell lines before and after treated with 5-Aza-Dc. The level of Cav-1 mRNA expression was no any change in AGS, MKN45 and BGC-823 cell lines treated with trichostatin A (TSA). MSP results showed that it can be amplified methylated bands in AGS cell line, and the methylated bands disappeared after treated with 5-Aza-Dc. MKN45 and BGC-823 cell lines were no any methylated bands amplified before and after treatment. The methylation frequency of Cav-1 gene was 29. 8% (31/104), which was significantly higher than that in adjacent tissues (P=0. 000). Furthermore, Cav-1 gene hypermethylation status was correlated with lymph node metastasis and family history of upper gastrointestinal cancers ( UGIC) , but not with pathological grade and clinical stage (P>0. 05). The positive frequency of Cav-1 expression was 51. 9%(54/104) in GC, which was significantly lower than that in adja-cent tissues (P=0. 000). The expression of Cav-1 was correlated with the frequency of gene methylation in GC tissues (P=0. 000). Conclusion The expression of Cav-1 was reduced in GC tissues and the gene hyermethylation may be one of the mechanisms causing Cav-1 gene silencing.

Expression and methylation status of CAV-1 gene in esophageal squamous cell carcinoma / 中国癌症杂志

Background and purpose: As one of the important epigenetic phenomena, DNA methylation plays an important regulatory function for the expression of genes. Study shows that abnormal changes of DNA methy-lation patterns of normal tumor cell genome leads to dysfunction of cancer related gene, and this may be associated with tumor occurrence and development. The study investigated the promoter methylation and expression of caveolin-1 (CAV-1) gene in esophageal squamous cell carcinoma (ESCC), and to elucidate its role in ESCC. Methods:We used MSP approach, RT-PCR, and immunohistochemistry method respectively to examine the methylation status of the 5’CpG island of CAV-1 gene and its expression at mRNA and protein levels in tumors and corresponding normal tissues. Results: CAV-1 mRNA expression in tumor tissues (0.86±0.56) was signiifcantly higher than that in corresponding normal tissues (0.40±0.36, P0.05). The promoter methylation frequency of CAV-1 in tumor specimens was 2.0%(1/51), and the methylation phenomenon has not been found in corresponding normal tissues. The promoter methylation fre-quency of CAV-1 in tumor specimens showed no signiifcant difference compared with the corresponding normal tissues (P>0.05). Conclusion:The mRNA and protein expression of CAV-1 in tumor specimens was signiifcantly higher than that in corresponding normal tissues. Aberrant high expression of CAV-1 has played a certain role in promoting tumori-genesis and lymph node metastasis. The expression both in ESCC and corresponding normal tissues has no correlation with the promoter methylation status.

Methylation status and expression of RASSF10 gene in gastric cardia adenocarcinoma / 中国癌症杂志

Background and purpose:RASSF10 acts as a kind of tumor suppressor in various tumor tissues, but researches in cardiac adenocarcinoma has not been reported. This study aimed to detect the methylation status and expression ofRas-association domain family 10 (RASSF10) in gastric cardia adenocarcinoma (GCA), and explore its role in occurrence and development of GCA.Methods:Methylation speciifc polymerase chain reaction (MSP), reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry method were respectively used to detect methylation status, mRNA expression and protein expression ofRASSF10 in 81 GCA tissues and corresponding normal tissues.Results:The promoter methylation frequency ofRASSF10 in GCA tissues (64.20%, 52/81) was signiifcantly higher than that in corresponding normal tissues (20.99%, 17/81,P<0.05), and was closely correlated with TNM stages, differential degree and lymph node metastasis (P<0.05). RASSF10 mRNA expression in GCA tissues (0.57±0.05) was significantly lower than that in corresponding normal tissues (0.78±0.02,P<0.05), and was closely correlated with TNM stages and lymph node metastasis (P<0.05). Protein expression of RASSF10 in GCA tissues (31.10%, 26/81) was signiifcantly lower than that in corresponding normal tissues (71.60%, 58/81,P<0.05), and was closely correlated with TNM stages, differential degree and lymph node metastasis (P<0.05). The promoter methylation frequency ofRASSF10 in GCA tissues was inversely related to its protein expression.Conclusion:Inactivation of RASSF10 caused by aberrantmethylation in the promoter region may be closely correlated with the GCA tumorgenesis.

Aberrant Methylation and Expression of Growth Arrest and DNA-Damage-Inducible 45G Gene in Gastric Cardia Adenocarcinoma / 天津医药

Objective To investigate the aberrant methylation and expression of growth arrest and DNA-damage-in-ducible 45 gamma (GADD45G) gene in gastric cardia adenocarcinoma (GCA). Methods Bisulfite conversion-methylation specific polymerase chain reaction method (BS-MSP) and immunohistochemistry method were used respectively to detect the methylation status and protein expression of GADD45G in 138 GCA tumor tissues and corresponding normal tissues. Re-sults The methylation status of GADD45G distal promoter (region 1) was not detected in GCA tumor tissues and corre-sponding normal tissues. For GADD45G region 2 and region 3, the BS-MSP results of region 3 were identical to that of re-gion 2. The methylation frequency of proximal promoter and exon 1 in GADD45G island 2 (region 2 and region 3) in GCA tu-mor tissues (49.3%, 68/138) was significantly increased compared to that in corresponding normal tissues (0, P＜0.01). The methylation status of this two sites in tumor tissues was associated with TNM stage of tumors (P＜0.05). The protein expres-sion of GADD45G in tumor tissues was significantly decreased than that in corresponding normal tissues (P ＜ 0.05),and threre was a significant negative correlation with methylation status of GADD45G proximal promoter and exon 1 (rs=-0.398). Conclusion The decreased expression of GADD45G by hypermethylation of proximal promoter exon 1 of the gene may play an important role in gastric cardia adenocarcinoma.

The expression of MnSOD and E-cadherin and its biological signficance in nasopharyngeal carcinoma / 中华放射肿瘤学杂志

Objective To investigate the expression of MnSOD and E-cadhefin in nasopharyngeal carcinoma(NPC) tissue and its relationship with clinicopathological features and prognosis. Methods The expression of MnSOD and E-cadherin were detected by immunohistochemistry method in 60 NPC patients. Results Of the whole group,lymph node positive group and lymph node negative group,the strong positive rate of MnSOD protein was 47% (28/60) ,49% (25/51 patients) and 33% (3/9) (x2 =0.76,P =0.382), respectively.The corresponding strong positive rate of E-cadherin protein was 47% (28/60) ,43% (22/51) and 78% (7/9) (x2 =3.69,P =0.047) ,respectively.The expression of MnSOD increased with T stage and N stage.The higher expression of MnSOD was significantly associated with the larger size of metastatic lymph node(r =0.46 ,P =0.002) ,more radioresistance and poorer prognosis,but not with the region of lymph node metastasis(r =0.223,P = 0.116).The lower expression of E-cadherin was closely relevant with higher N stage and the smaller region of lymph node metastasis(r =-0.33,P = 0.020),but not with T stage,lymph node size or radiosensitivity(r =-2.19,P=0.093;r=-0.07,P=0.623;r=-0.18,P=0.170).Multi variate analysis showed that MnSOD and E-canherin were independent prognostic factors (x2= 4.45,P = 0.035;x2 =5.12,P=0.024). Conclusions High expression of MnSOD may stimulate tumor growth and reduce radiosensitivity.High expression of E-cadherin may inhibit lymphatic metastasis,while has no rela tionship with tumor growth and invasion.MnSOD and E-cadherin could affect the prognosis of NPC patients.

Aberrant promoter methylation of SFRP1 and SFRP2 gene in gastric cardia adenocarcinoma / 肿瘤研究与临床

Objective To investigate the promoter methylation status of SFRP1 and SFRP2 gene in gastric cardia adenocarcinoma (GCA). Methods Methylation specific PCR (MSP) method was used to examine the methylation status of the 5' CpG island of SFRP1 and SFRP2 gene in tumors and corresponding normal tissues. Results Methylation frequencies of SFRP1 and SFRP2 gene in tumor specimens were 87.2 % (82/94) and 83 %(78/94), which was significantly higher than that in corresponding normal tissues (14.9 % and 55.3 %, respectively) (P <0.001). Methylation frequencies of SFRP1 in lymph node metastasis group (96.4 %) was significantly higher than that in no lymph node metastasis group (73.7 %). Methylation frequencies of SFRP1 and SFRP2 gene in poor differentiation group were all higher than that in moderate and poor-moderate differentiation groups, but both of them did not show significant difference(P >0.05). 63 cases of GCA showed both of SFRP1 and SFRP2 gene simultaneous methylation, which including 36 cases of lymph node metastasis group, 27 cases of no lymph node metastasis group. Simultaneous methylation frequencies of SFRP1 and SFRP2 gene in lymph node metastasis group was higher than that in no lymph node metastasis group, poor differentiation group was higher than that in moderate and poor-moderate differentiation groups, but both of them did not show significant difference (P >0.05). Conclusion Promoter methylation of SFRP1 and SFRP2 might be related with oncogenesis of GCA and hypermethylation of SFRP1 gene might be related with the malignant behavior of GCA.

Pilot research of the expression of MMP-2 gene and Survivin gene in primary esophageal cancer and subclinical microscopic tumor / 中华放射肿瘤学杂志

Objective To examine the expression of MMP-2 gene and Survivin gene in subclinical microscopic tumor and its peripheral normal esophageal tissues,and study the radiation target in molecular level. Methods Esophageal squamous cancer and its peripheral tissue samples of 34 patients were cut into sequential sections.The expression of MMP-2 gene and Survivin gene then examined.The length of the peripheral esophageal tissue,positively expressing the two genes,was measured,and the relation among the experimental date,tumor stage and vertical length of tumor were analyzed. Results For tumor tissue,subclinical microscopic tumor and the peripheral differentiated normal tissue,the positive expression rate of MMP-2 was 85%,83%and 79%,respectively.The positive expression rate of Survivin was 76%,85%and 85%,respectively.The positive expression level of both MMP-2 and Survivin genes in subclinical microscopic tumor was significantly higher than that in the peripheral differentiated normal tissue(χ2=6.46,P=0.028 and χ2=16.15,P=0.001).The length was 17.2-70.4 mm and 15.0-82.4 mm of cancerous peripheral tissue with positive expression of MMP-2 gene upside and downside of the tumor.The length was＜70 mm in 97% of the samples.For Survivin gene.the length was 3.7-76.4 mm and 16.1-56.3 mm.and was＜70 mm in 96%of the samples.The length of cancerous peripheral esophageal tissue expressing the two genes increased significantly along with tumor stage or tumor length,and there was statistical correlation between the length of tumor and the positive expression ranges of Survivin gene. Conclusions Both MMP-2 gene and Survivin gene are positively expressed in esophageal cancerous peripheral tissue.The range positively expressing the two genes is＜70 mm in more than 96%of the samples,and the length is correlated with the tumor stage.More attention should be paid to the peripheral differentiated normal tissue with positive expression of MMP-2 gene and Survivin gene in esophageal squamous carcinoma.