Clinical characterization and mutation spectrum in patients with familial adenomatous polyposis in China.

BACKGROUND AND AIM: Familial adenomatous polyposis (FAP) is the most common adenomatous polyposis syndrome. Patients with FAP are screened for germline mutations of two genes, APC and MUTYH. However, limited data exist on the clinical characterization and genotypic spectrum of FAP in China. This study was aimed to determine APC and MUTYH mutational status in a small cohort of FAP probands in China and to characterize the genotype-phenotype correlation in mutated patients. METHODS: Mutation screening of 46 unrelated probands was performed using multigene panels by next-generation sequencing. Clinical data of the index were used to assess genotype-phenotype correlations. RESULTS: Overall, 42 out of 46 (91.30%) unrelated probands found mutations, including 35 (76.09%) with APC mutations, 3 (6.52%) with MUTYH mutations, and 4 (8.70%) with both APC and MUTYH mutations. Ten APC genetic alterations variants were novel. The hereditary pattern of the family with both APC and MUTYH mutations was autosomal dominant inheritance. Upper gastrointestinal polyp was the most common extracolonic manifestations. The onset time for patients with both APC and MUTYH mutations was earlier than MUTYH mutation carriers and similar to APC mutation carriers. But the age of carcinogenesis for patients with both APC and MUTYH mutations was later than APC mutation carriers and similar to MUTYH mutation carriers. CONCLUSION: In this study, we show the importance of using multigene panels that allow for a parallel comprehensive screening. We suggest that genetic testing of patients with suspected adenomatous polyposis syndromes should include APC and MUTYH gene mutation analyses simultaneously.

Artificial intelligence system of faster region-based convolutional neural network surpassing senior radiologists in evaluation of metastatic lymph nodes of rectal cancer.

BACKGROUND: An artificial intelligence system of Faster Region-based Convolutional Neural Network (Faster R-CNN) is newly developed for the diagnosis of metastatic lymph node (LN) in rectal cancer patients. The primary objective of this study was to comprehensively verify its accuracy in clinical use. METHODS: Four hundred fourteen patients with rectal cancer discharged between January 2013 and March 2015 were collected from 6 clinical centers, and the magnetic resonance imaging data for pelvic metastatic LNs of each patient was identified by Faster R-CNN. Faster R-CNN based diagnoses were compared with radiologist based diagnoses and pathologist based diagnoses for methodological verification, using correlation analyses and consistency check. For clinical verification, the patients were retrospectively followed up by telephone for 36 months, with post-operative recurrence of rectal cancer as a clinical outcome; recurrence-free survivals of the patients were compared among different diagnostic groups, by methods of Kaplan-Meier and Cox hazards regression model. RESULTS: Significant correlations were observed between any 2 factors among the numbers of metastatic LNs separately diagnosed by radiologists, Faster R-CNN and pathologists, as evidenced by rradiologist-Faster R-CNN of 0.912, rPathologist-radiologist of 0.134, and rPathologist-Faster R-CNN of 0.448 respectively. The value of kappa coefficient in N staging between Faster R-CNN and pathologists was 0.573, and this value between radiologists and pathologists was 0.473. The 3 groups of Faster R-CNN, radiologists and pathologists showed no significant differences in the recurrence-free survival time for stage N0 and N1 patients, but significant differences were found for stage N2 patients. CONCLUSION: Faster R-CNN surpasses radiologists in the evaluation of pelvic metastatic LNs of rectal cancer, but is not on par with pathologists. TRIAL REGISTRATION: www.chictr.org.cn (No. ChiCTR-DDD-17013842).

Concordance Study Between IBM Watson for Oncology and Clinical Practice for Patients with Cancer in China.

BACKGROUND: IBM Watson for Oncology (WFO), which can use natural language processing to evaluate data in structured and unstructured formats, has begun to be used in China. It provides physicians with evidence-based treatment options and ranks them in three categories for treatment decision support. This study was designed to examine the concordance between the treatment recommendation proposed by WFO and actual clinical decisions by oncologists in our cancer center, which would reflect the differences of cancer treatment between China and the U.S. PATIENTS AND METHODS: Retrospective data from 362 patients with cancer were ingested into WFO from April 2017 to October 2017. WFO recommendations were provided in three categories: recommended, for consideration, and not recommended. Concordance was analyzed by comparing the treatment decisions proposed by WFO with those of the multidisciplinary tumor board. Concordance was achieved when the oncologists' treatment decisions were in the recommended or for consideration categories in WFO. RESULTS: Ovarian cancer showed the highest concordance, which was 96%. Lung cancer and breast cancer obtained a concordance of slightly above 80%. The concordance of rectal cancer was 74%, whereas colon cancer and cervical cancer showed the same concordance of 64%. In particular, the concordance of gastric cancer was very low, only 12%, and 88% of cases were under physicians choice. CONCLUSION: Different cancer types showed different concordances, and only gastric cancers were significantly less likely to be concordant. Incidence and pharmaceuticals may be the major cause of discordance. To be comprehensively and rapidly applied in China, WFO needs to accelerate localization. ClinicalTrials.gov Identifier: NCT03400514. IMPLICATIONS FOR PRACTICE: IBM Watson for Oncology (WFO) has begun to be used in China. In this study, concordance was examined between the treatment recommendation proposed by WFO and clinical decisions for 362 patients in our cancer center, which could reflect the differences of cancer treatment between China and the U.S. Different cancer types showed different concordances, and only gastric cancers were significantly less likely to be concordant. Incidence and pharmaceuticals may be the major causes of discordance. To be comprehensively and rapidly applied in China, WFO needs to accelerate localization. This study may have a significant effect on application of artificial intelligence systems in China.

Predictive Value of Stemness Factor Sox2 in Gastric Cancer Is Associated with Tumor Location and Stage.

Cancer stem cells (CSCs) are thought to be the "root" of cancer. Although stemness-related factors ALDH1A1 and Sox2 have been used as markers to identify gastric CSCs, the expression pattern and significance of these factors in gastric cancer have not been sufficiently demonstrated. In this study, the expressions of ALDH1A1 and Sox2 were detected by immunohistochemistry in 122 gastric cancer specimens. And the correlation between Sox2 or ALDH1A1 expression and clinicopathological parameters and overall survival data were analyzed. The positive rate of ALDH1A1 expression was 60%, but there was no significant difference between survival rates of ALDH1A1-positive and ALDH1A1-negative patients. Sox2 was expressed in 42% of specimens and was associated with poor prognosis of patients (P = 0.015). Stratified analysis showed that Sox2 expression correlated with shorter lifespan only in patients with cardiac gastric cancers (P = 0.002) or stage I or II gastric cancers (P = 0.002); but not in patients with non-cardiac cancers (P = 0.556) or stage III or IV gastric cancers (P = 0.121). Analysis on a database cohort validated the correlation between Sox2 expression and poor prognosis in stage II cancer. Also, expression of Sox2 was associated with lymphnode metastasis in patients with cardiac gastric cancer (P = 0.037). A multivariate analysis revealed that Sox2 was an independent prognostic factor in cardiac gastric cancer. Our results indicate that predictive value of Sox2 in gastric cancer is associated with cardiac cancer location and with early cancer stages (I and II).

Factors for Endoscopic Submucosal Dissection in Early Colorectal Neoplasms: A Single Center Clinical Experience in China.

BACKGROUND/AIMS: Early colorectal (CR) neoplasm can be cured by endoscopic submucosal dissection (ESD), but clinical experience and factors associated with complications from ESD for CR neoplasms in China have not been reported. METHODS: Seventy-eight cases of early CR neoplasm treated with endoscopic resection performed between December 2012 and December 2013 at Beijing Military General Hospital were included. Factors associated with ESD complications and procedure times were evaluated. RESULTS: The en bloc resection rate was 88.5% (69/78), tumor size was 32.1±10.7 mm, and procedure time was 71.8±49.5 minutes. The major complication was perforation, which occurred in 8.97% of the ESD procedures. Multivariate logistic regression analysis indicated that only tumor size (p=0.022) was associated with ESD perforation. Tumor size (p<0.001) and the non-lifting sign (p=0.017) were independent factors for procedure time, and procedure time (p=0.016) was a key factor for en bloc resection. After a median 10 months (range, 4 to 16) of follow-up, no patients had local recurrence. CONCLUSIONS: This study indicated that ESD is an applicable method for large early CR neoplasm in the colon and rectum. Tumor size and the non-lifting sign might be considerable factors for increased complication rate and procedural time of ESD.

[Oral candida species distribution in patients receiving radiotherapy for head and neck cancer].

PURPOSE: To investigate the distribution of oral candida species in head and neck cancer (HNC) patients treated with radiation therapy, and provide the basis for planning of clinical preventive measures. METHODS: Saliva was sampled from 60 HNC patients before, during and after radiation. Concomitantly, 60 healthy individuals whose age and sex matched that of the patient group were selected as control group. Oral candida carriages were quantitatively detected and the different candida species were identified by multiple measures such as CHROMagar candida culture medium and API 20C AUX yeast identification system. Then the differences between the two groups in terms of the candida detection rate and the distribution of each species of candida were analyzed with SPSS 17.0 software package. RESULTS: Xerostomia and dysphagia was found in 54 HNC patients during radiotherapy, radiation-induced oral mucotitis(RIOM) was found in 50 HNC patients,and oral candidiasis was found in 18 HNC patients; In radiation group, the detection rate of candida colonization during radiation was 56.7%, 63.3% postradiation, which showed significant differences compared with pre-radiation (X² =18.320,P<0.001 ); Among the 54 identified clinical isolates, candida albicans (n=42) was the most frequent, followed by candida parapsilosis (n=6), candida tropicalis (n=4) and candida glabrata (n=2). In radiation group, the oral candida pathogens detection rate was 30%, and candida colonization was 46.7%. CONCLUSIONS: The oral candida colonization rate was significantly higher in HNC patients after radiotherapy, which indicated that the candida infection may be closely related to RIOM.

Mismatch repair gene mutation analysis and colonoscopy surveillance in Chinese Lynch syndrome families.

BACKGROUND: Lynch syndrome (or HNPCC) is a colorectal cancer syndrome caused by germline mutations in either one of the DNA mismatch repair (MMR) genes hMLH1, hMSH2, hMSH6 or hPMS2. Mutations in hMLH1 and hMSH2 are most prevalent. Here we aimed to determine the cancer risk of MMR gene mutation carriers and, in addition, the efficacy of colonoscopy surveillance in Chinese Lynch syndrome family members with and without MMR gene mutations. METHODS: A Lynch syndrome family registry encompassing 106 families in Northern China was recently established. Detailed pedigree data for each family were collected and hMLH1 and hMSH2 gene mutation analyses were performed. Germ-line mutations were identified in probands from 42 of these families, and additional genetic analyses were performed in each member of these 42 families to identify mutation and non-mutation carriers. Among the family members included, 180 received colonoscopy and the remaining cases were followed without colonoscopy. RESULTS: Overall 54.8 % of the Lynch syndrome family members carried MMR gene mutations, and these mutation carriers exhibited significantly higher colorectal cancer and other Lynch syndrome-associated cancer risks as compared to non-mutation carriers. The cumulative risk for all Lynch syndrome-related cancers at age 70 was 93.8 % for both hMLH1 and hMSH2 mutation carriers, and 81.7 % and 93.1 % for colorectal cancer at this age, respectively. Whereas 43 of 102 (42.2 %) mutation carriers exhibited significant colonoscopy findings, including 10 colorectal cancers, none of 78 non-mutation carriers exhibited significant findings, and no cancers were detected. In addition, in the mutation carriers, colonoscopy surveillance led to the detection of more early stage cancers than in the non-surveillance group (70.0 % versus 36.5 %, p < 0.01). CONCLUSION: In Lynch syndrome family members, we recommend pre-symptomatic MMR gene mutation analysis in order to identify high risk individuals for colonoscopy surveillance.

Identification of SSR markers using soybean (Glycine max) ESTs from globular stage embryos

Microsatellites, or simple sequence repeats (SSRs), in expressed sequence tags (ESTs) provide an opportunity for low cost SSR development. We looked for EST-SSRs in 403,511 ESTs (generated by 454 sequencing and representing 70,654 contigs and 52,082 singletons) from soybean globular stage embryos. Among 122,736 unique ESTs, 3,729 contained one or more SSRs. In total, 3,989 SSRs were identified including 304 mono, 1,374 di, 2,208 tri, 70 tetra, 13 penta and 20 hexanucleotide SSRs. Thirty three EST-SSRs were selected for primer design and polymorphism analysis using twenty soybean cultivars and one wild-type soybean. Successful amplification was obtained using 21 of these primer pairs, 11 of which detected polymorphisms in these soybean cultivars. These results demonstrated that 454 high throughput sequencing is a powerful tool for molecular marker development. From the 3,989 identified SSRs we expect to obtain a large number of makers with polymorphism among different soybean cultivars, which would be useful for analysis of genetic diversity and maker assisted selection in the soybean breeding programs.

[Detection of APC gene germline mutation in Chinese familial adenomatous polyposis by direct sequencing in combination with multiplex ligation-dependent probe amplification].

OBJECTIVE: To investigate the characteristics of APC gene germline mutation in Chinese patients with familial adenomatous polyposis (FAP). METHODS: The genomic DNA was extracted from peripheral venous blood drawn from probands of 14 Chinese FAP families from Beijing, Hebei, Henan, Anhui, Inner Mongolia, Shanxi and Fujian. The APC gene was amplified by PCR and underwent direct sequencing. Large fragment deletion was detected by multiplex ligation-dependent probe amplification (MLPA) only in micromutation-negative samples found by sequencing. RESULTS: APC gene micromutations were found in 9 probands and the micromutation detection rate was 64.3%, including 6 frameshift mutations, 2 splicing mutations and 1 nonsense mutation. Large fragment deletions of APC gene were detected in 2 probands (14.3%). The total mutation detection rate of micromutation and large fragment deletion was 78.6%. Four novel micromutations and 2 novel large fragment deletions were found, including c.2336-2337insT, c.3923-3929delAAGAAAA, c.532-2A > T, c.4179-4180GAdelinsT, large fragment deletions of exons 11 and 10A and large fragment deletion of exon 15 start. CONCLUSIONS: In Chinese FAP patients, the germline mutation type of APC gene is variable; the majority is of frameshift mutation. The most common mutation site is exon 15. The mutation detection rate of APC gene can be boosted effectively by direct sequencing in combination with MLPA.

APC gene mutations in Chinese familial adenomatous polyposis patients.

AIM: To study the characteristics of APC (adenomatous polyposis coli) gene germline mutation in Chinese patients with familial adenomatous polyposis (FAP). METHODS: APC gene from 14 FAP families was amplified by polymerase chain reaction (PCR) and underwent direct sequencing to determine the micromutation type. For the samples without micromutation, the large fragment deletion of APC gene was examined by multiplex ligation-dependent probe amplification (MLPA). RESULTS: There were gene micromutations in 9 families with a micromutation detection rate of 64.3% (9/14), including 6 frameshift mutations (66.7%), 1 nonsense mutation (11.1%) and 2 splicing mutations (22.2%). Large fragment deletions were detected by MLPA in 2 families. The total mutation detection rate of micromutations and large fragment deletions was 78.6% (11/14). CONCLUSION: The detection rate of APC gene germline mutation can be improved by direct sequencing combined with MLPA large fragment deletion detection.

[Effects of cyclooxygenase-2 and proliferating cell nuclear antigen on the onset and development of familial adenomatous polyposis].

BACKGROUND AND OBJECTIVE: Long-term use of cyclooxygenase-2 (COX-2) inhibitors can reduce the incidence of digestive cancers, such as colorectal cancers. Proliferating cell nuclear antigen (PCNA) is an important marker of cellular abnormal proliferation. This study was to evaluate the roles and correlation of COX-2 and PCNA in the onset and development of familial adenomatous polyposis (FAP) diseases. METHODS: Thirty-six specimens of FAP adenomas tissues and 32 specimens of FAP carcinoma tissues from 11 FAP families, and 34 specimens of normal colonic mucosa were collected under colonoscopy from November 2004 to July 2007 in the General Hospital of Beijing Military Command. Immunohistochemistry was used to detect the expressions of COX-2 and PCNA. RESULTS: The positive expression rates of COX-2 in normal colonic mucosa, FAP adenoma, and carcinoma tissues were 0 (0/34), 80.6% (29/36), and 93.8% (30/32), respectively. Proliferation index (PI) in normal mucosa, FAP adenoma, and carcinoma tissues were 17.79+/-7.49, 34.47+/-10.57, and 71.75+/-9.22, respectively. Expressions of COX-2 and PCNA were significantly higher in the FAP adenoma and the carcinoma tissues than in the normal colonic mucosa(P<0.01). The expression of PCNA was significantly higher in the FAP carcinoma tissues than in the FAP adenoma (P<0.01). The expression of PCNA was higher in the FAP adenoma tissues with positive COX-2 than in the FAP adenomas tissues with negative COX-2 (P<0.01). CONCLUSIONS: COX-2 may play an important role in the development of FAP adenomas and colorectal carcinogenesis. COX-2 and PCNA may be important factors in the research on colorectal precancerous lesions and interventional therapy for colorectal neoplasm.

[Expression of cyclooxygenase-2 and relationship with mismatch repair gene and microsatellite instability in hereditary non-polyposis colorectal cancer].

OBJECTIVE: To investigate the expression of Cyclooxygenase (COX)-2 and the relationship between cox-2, mismatch repair gene (MMR) proteins and microsatellite instability (MSI) in HNPCC. METHODS: Twenty-eight cases of adenomas and 14 cases of carcinomas were collected from 33 HNPCC families patients by colonoscopy. Sporadic adenomas (n = 32) and carcinomas (n = 24) were used as a control group. The expressions of COX-2 and mismatch repair gene hMLH1, hMSH2, hMSH6 proteins were examined by immunohistochemistry. MS1 were analyzed by using PCR with BAT25, BAT26, D2S123, D5S346 and D17S250 loci. RESULTS: The COX-2 high-expression rates were 53.6% (15/28) and 42.9% (6/14) in HNPCC adenomas and carcinomas, and were 62.5% (20/32) and 91.7% (22/24) in sporadic adenomas and carcinomas. COX-2 expression was lower in HNPCC carcinomas than that of sporadic carcinomas (P < 0.05). MMR deficiency rate and positive rate of MSI-H were both 71.4% (10/14) respectively in HNPCC carcinomas. It was higher than that in sporadic colorectal carcinomas [both 12.5% (3/24)]. Eight (80.0%) COX-2 low-expression were observed in 10 HNPCC carcinomas with MMR-deficient system while 4 cox-2 high-expression cases were observed in 4 HNPCC carcinomas with MMR-proficient system. COX-2 expression was lower in HNPCC carcinomas and adenomas, sporadic carcinomas with MMR-deficient system than that of MMR-proficient (P < 0.05). The COX-2 low-expression rates were 80.0% (8/10), 66.7% (12/18) and 66.7% (2/3) in HNPCC adenomas, HNPCC carcinomas and sporadic carcinomas with MSI-H. Cox-2 expression was lower in HNPCC and sporadic carcinomas (adenocarcinomas) with MSI-H than that of MSS (P < 0.05). CONCLUSION: Compared with sporadic carcinomas, the COX-2 expression was lower in HNPCC carcinomas. There was negative correlation between COX-2 expression and MMR-deficient (MSI-H). The detection of COX-2, MMR protein and MSI is of important significance in further studying the pathogenesis and interventional therapy of colorectal neoplasms.

Genetic diagnosis strategy of hereditary non-polyposis colorectal cancer.

AIM: To study the characteristics of mismatch repair gene mutation of Chinese hereditary non-polyposis colorectal cancer (HNPCC) and hMLH1 gene promoter methylation, and to improve the screening strategy and explore the pertinent test methods. METHODS: A systematic analysis of 30 probands from HNPCC families in the north of China was performed by immunohistochemistry, microsatellite instability (MSI), gene mutation and methylation detection. RESULTS: High frequency microsatellite instability occurred in 25 probands (83.3%) of HNPCC family. Loss of hMLH1 and hMSH2 protein expression accounted for 88% of all microsatellite instability. Pathogenic mutation occurred in 14 samples and 3 novel mutational sites were discovered. Deletion of exons 1-6, 1-7 and 8 of hMSH2 was detected in 3 samples and no large fragment deletion was found in hMLH1. Of the 30 probands, hMLH1 gene promoter methylation occurred in 3 probands. The rate of gene micromutation detection combined with large fragment deletion detection was 46.7%-56.7%. The rate of the two methods in combination with methylation detection was 63.3%. CONCLUSION: Scientific and rational detection strategy can improve the detection rate of HNPCC. Based on traditional molecular genetics and combined with epigenetics, multiple detection methods can accurately diagnose HNPCC.