Biomedical subjects

Ying Yuan

Publications and source records attributed to Ying Yuan.

At least 19 recordsLinked to original sources

PubMed2025

PoweREST: Statistical power estimation for spatial transcriptomics experiments to detect differentially expressed genes between two conditions.

Recent advancements in spatial transcriptomics (ST) have significantly enhanced biological research in various domains. However, the high cost for current ST data generation techniques restricts the large-scale application of ST. Consequently, maximization of the use of available resources to achieve robust statistical power for ST data is a pressing need. One fundamental question in ST analysis is detection of differentially expressed genes (DEGs) under different conditions using ST data. Such DEG analyses are performed frequently, but their power calculations are rarely discussed in the literature. To address this gap, we developed PoweREST, a power estimation tool designed to support the power calculation for DEG detection with 10X Genomics Visium data. PoweREST enables power estimation both before any ST experiments and after preliminary data are collected, making it suitable for a wide variety of power analyses in ST studies. We also provide a user-friendly, program-free web application that allows users to interactively calculate and visualize study power along with relevant parameters.

Gene Expression Profiling↗

PubMed2024

PoweREST: Statistical Power Estimation for Spatial Transcriptomics Experiments to Detect Differentially Expressed Genes Between Two Conditions.

Recent advancements in Spatial Transcriptomics (ST) have significantly enhanced biological research in various domains. However, the high cost of current ST data generation techniques restricts its application in large-scale population studies. Consequently, there is a pressing need to maximize the use of available resources to achieve robust statistical power. One fundamental question in ST analysis is to detect differentially expressed genes (DEGs) among different conditions using ST data. Such DEG analysis is often performed but the associated power calculation is rarely discussed in the literature. To address this gap, we introduce, PoweREST (https://github.com/lanshui98/PoweREST), a power estimation tool designed to support power calculation of DEG detection with 10X Genomics Visium data. PoweREST enables power estimation both before any ST experiments or after preliminary data are collected, making it suitable for a wide variety of power analyses in ST studies. We also provide a user-friendly, program-free web application (https://lanshui.shinyapps.io/PoweREST/), allowing users to interactively calculate and visualize the study power along with relevant the parameters.

Differentially expressed genes↗

PubMed2006

Clinical and genetic characteristics of Chinese hereditary nonpolyposis colorectal cancer families.

AIM: To analyze the clinical characteristics of Chinese hereditary nonpolyposis colorectal cancer (HNPCC) families and to screen the germline mutations of human mismatch repair genes hMLH1 and hMSH2 in the probands. METHODS: Thirty-one independent Chinese HNPCC families were collected in Zhejiang Province. All of them met Chinese HNPCC criteria. Clinical data about patient gender, site of colorectal cancer, age of onset, history of multiple colorectal cancer, associated extracolonic cancer were recorded. PCR and denaturing high performance liquid chromatography (DHPLC) were employed to screen the mutations. Sequencing analysis was used to find out the exact mutation site and characteristics of the samples showing abnormal DHPLC profiles. RESULTS: One hundred and thirty-six malignant neoplasms were found in 107 patients including 14 multiple cancers. One hundred and six of the 136 neoplasms (77.9%) were diagnosed as colorectal cancer, with an average age of onset at 48.57 +/- 29.00 years. Gastric cancer was the most common extracolonic cancer (10.3%) in these families. Twenty-three different sequence variations in hMLHl and hMSH2 genes were detected in these 17 families. Fifteen sequence variations were located in the exons, including 5 SNPs, 3 silent mutations, 3 missense mutations, 2 nonsense mutations and 2 frameshift mutations. The latter seven mutations seemed to be pathogenic. CONCLUSION: Germline mutations of hMLH1 and hMSH2 genes are identified in about one-third HNPCC kindreds fulfilling Chinese HNPCC criteria. Chinese HNPCC families have some particular clinical characteristics, such as a left-sided predominance, less synchronous or metachronous colorectal cancer, and frequent occurrence of gastric cancer.

Adaptor Proteins, Signal Transducing↗

PubMed2006

Effects of estradiol and progesterone on tumor necrosis factor alpha-induced apoptosis in human hepatoma HuH-7 cells.

Oxidative stress, including the generation of reactive oxygen species (ROS), is known to be involved in apoptosis. Preventing apoptosis may thereby induce a malignant transformation of liver tumor cells. Estradiol (E2) is a potent endogenous antioxidant. We examined the proapoptotic role of progesterone as well as the antiapoptotic role of E2 in human hepatoma HuH-7 cells in a state of early apoptosis induced by tumor necrosis factor (TNF) alpha. The TNF alpha-induced ROS generation, lipid peroxidation, antioxidant enzyme consumption, a proapoptotic predominant expression of Bcl-2 family proteins, and a disruption of mitochondrial membrane potential were all inhibited by E2, and then they were further stimulated by progesterone in HuH-7 cells. The inhibitory effects of E2 were blocked by coincubation with progesterone. Treatment with the progesterone receptor antagonist RU486 led to the blockage of the progesterone-mediated responses to E2 pretreatment in TNF alpha-induced apoptosis. These findings demonstrate that E2 inhibits the TNF alpha-induced early apoptosis in hepatoma cells, by suppressing the oxidative stress processes, whereas progesterone acts in a manner opposite from the effects of E2, and the inhibitory effects of E2 were blocked by progesterone, thus leading to the apoptosis of hepatoma cells.

Antibodies, Monoclonal↗

PubMed2006

Dietary patterns related to caries in a low-income adult population.

The aim of this study was to examine the relationship between dietary patterns and caries experience in a representative group of low-income African-American adults. Participants were residents of Detroit, Michigan, with household incomes below 250% of the federally-established poverty level (n = 1,021). Dietary histories were obtained by trained interviewers in face-to-face interviews with the adult participants, using the Block 98.2 food frequency questionnaire. Caries was measured by the ICDAS criteria (International Caries Detection and Assessment System). There were 200 dietary records whose data were judged to be invalid; these participants were omitted from the dietary analyses to leave n = 821. Factor analysis identified patterns of liquid and solid food consumption, and the resulting factor scores were used as covariates in multivariable linear regression. Caries was extensive, with 82.3% of the 1,021 participants (n = 839) having at least one cavitated lesion. Nearly three quarters of the adult participants were overweight or obese. This population had severe caries, poor oral hygiene, and diets that are high in sugars and fats and low in fruits and vegetables. Apart from tap water, the most frequently consumed food item by adults of all ages was soft drinks; 19% of all energy from sugar came from soft drinks alone. In both the bivariate analyses and in the regression model, frequency of soft drink consumption and the presence of gingival plaque deposits were significantly associated with caries. Interventions to promote oral health are unlikely to be successful without improvements in the social and physical environment.

Adolescent↗

PubMed2006

A histochemical and immunohistochemical investigation of guanase and nedasin in rat and human tissues.

Human guanase is known as a specific enzyme in the liver, kidney, and brain. However, its functional significance remains poorly understood. In addition, interestingly, a different organ distribution between humans and rats was suggested. Here, we performed immunohistochemical staining with anti-human nedasin (neuronal and endocrine discs large/SAP102 associated protein), whose sequence was identical to that of guanase, antibody and histochemical staining for guanase in normal tissues of rat and human liver, kidney, and small intestine, and compared the results. Guanase activity was observed uniformly in the rat hepatocytes, biliary epithelium and vascular endothelium cells, while it was localized to the hepatocytes and biliary epithelium in the human liver. When the histochemical staining for guanase and the immunohistochemical staining for nedasin were compared, the stained regions were different in the rat liver but were almost consistent in all human tissues. Totally consistent staining results were also obtained between rats and humans in the other organization except the liver. Based upon the research reports to date, the experiments on guanase and nedasin in rat organs performed in this study are considered to have important implications in the investigation of their physiological significance.

Aminohydrolases↗

PubMed2006

Cost-efficient higher-order crossover designs in comparative bioavailability studies.

BACKGROUND AND OBJECTIVE: Cost is an extremely important factor to consider when planning drug clinical trials. Higher-order crossover designs have recently drawn considerable attention in comparative bioavailability studies because of their desirable statistical properties. In this paper, we compared the cost efficiency of five commonly used higher-order crossover designs under certain cost function for comparative bioavailability studies. METHODS: Multivariate normal data were simulated under scenarios of a wide range of variability and correlations (coefficient of variation = 10-40%; correlation coefficient rho = 0.2-0.8). Monte Carlo simulations and mixed-effects models were carried out to obtain empirical sample sizes for each design using Schuirmann's two-one sided test procedure, under an 80% power and a 5% significance level, based on the US FDA bioequivalence criteria (80-125%). The five crossover designs studied were the two-period four-sequence (D2 x 4), the three-period two-sequence (D3 x 2), the three-period four-sequence (D3 x 4), the four-period two-sequence (D4 x 2), and the four-period four-sequence (D4 x 4). Costs for each design were then determined by a cost function, which takes into account costs for recruiting and screening, costs associated with period, and the overheads incurred for multiple sequences. Comparison of the costs for the above-mentioned designs was made under different scenarios. RESULTS: There was no single design uniformly dominating the others in terms of cost efficiency for comparative bioavailability studies. The designs D3 x 2 and D4 x 4 (especially the former) have the best overall performance in terms of cost efficiency for comparative bioavailability studies. They dominated the other designs under most of the scenarios. The design D2 x 4 showed the worst performance among the five crossover designs. CONCLUSIONS: A D3 x 2, and D4 x 2 crossover designs are recommended to achieve cost efficiency with a given power. The D2 x 4 crossover design is not recommended in general for comparative bioavailability studies.

Biological Availability↗

PubMed2006

[Clinical phenotype of Chinese hereditary nonpolyposis colorectal cancer (HNPCC) families].

OBJECTIVE: To characterize the clinical features of Chinese hereditary nonpolyposis colorectal cancer (HNPCC) families and to evaluate the value of Chinese HNPCC criteria. METHODS: Twenty-six families were involved in this study. Eight families fulfilled both the Amsterdam criteria and the Chinese HNPCC criteria (named group A), while the other 18 families fulfilled the Chinese HNPCC criteria only (named group B). The clinical features of these HNPCC families were compared with those of 509 sporadic colorectal cancers (CRC) cases. Features of families in group A and in group B were also compared and analyzed. RESULTS: A total of 86 colorectal carcinomas developed in 77 patients in these 26 families. Synchronous or metachronous colorectal cancers developed in seven (9.1%) patients. Thirty-nine percent of colorectal carcinomas were developed in the proximal colon. Fifty-one out of 71 patients (71.8%) were diagnosed before the age of 50. A total of 24 extracolonic malignancies were identified in these families. Gastric carcinoma was the most common type of extracolonic malignancy (37.5%). Compared with sporadic CRCs, HNPCC patients were significantly younger at the age of diagnosis, namely, higher proportion of patients less than 50 years old, and more frequent development of multiple colorectal cancers. Except for the average number of colorectal carcinomas developed per family (4.5:2.3, P = 0.022), there was no significant difference between group A and B regarding the age of diagnosis, the location of colorectal cancer, the development of multiple colorectal cancers and the distribution of extra-colonic malignancies. CONCLUSION: Chinese HNPCC families have certain specific clinico-pathological features. Families in accord with the Chinese HNPCC criteria have similar clinical features as those with the Amsterdam criteria. The Chinese criteria are, however, more suitable for the diagnosis of patients from small families.

Adult↗

PubMed2006

[Multiple plane operations in treating severe obstructive sleep apnea-hypopnea syndrome].

OBJECTIVE: To investigate the effect and clinical value of multiple plane operations in treating severe OSAHS. METHOD: The clinical data of 28 patients with severe OSAHS were retrospectively analyzed. All the patients were performed two planes of operations or more as below: submucous nasal septum resection, nasal sinus endoscopy, adenoidectomy, uvulopalatopharyngoplasty (UPPP), tongue base incision, hyoid suspension, tongue base Coblation etc. Operations were finished in the same term or by stages. All patients underwent polysomnography(PSG) examination before operation, and 6-month and 1-year after surgical treatment separately. RESULT: No severe complication occurred, the 6-month, 1-year responders are 100% and 89.29% respectively. Both AHI and LSaO2 changed obviously (P < 0.01). CONCLUSION: Most OSAHS have multi-level obstructions in upper airway caliber, such as nasal, nasopharyngeal, velo-pharyngeal and tongue-pharyngeal obstruction. Multiple plane operations which based on idiographic obstruction sites can improve curative effect. Operation project should be established according to the conditions of upper airway and patients' intention.

Adult↗

PubMed2005

[Mutation detection of mismatch repair genes in hereditary nonpolyposis colorectal cancer by denaturing high-performance liquid chromatography].

OBJECTIVES: To establish DHPLC method in detecting mutations of mismatch repair genes, hMLH1 and hMSH2, and to identify germline mutations of hMLH1 and hMSH2 in HNPCC kindreds fulfilling Chinese HNPCC criteria. METHODS: Fourteen peripheral blood DNA samples from 14 unrelated HNPCC probands fulfilling Chinese HNPCC criteria were obtained respectively. PCR amplified 35 exons of two main mismatch repair genes, hMLH1 and hMSH2. DHPLC followed by DNA sequencing was used to detect and confirm mutations. RESULTS: a total of 41 colorectal cancers and 19 extracolonic tumors were developed in 14 HNPCC kindreds, and gastric cancer was the most common extracolonic tumor type. Twelve single nucleotide changes were identified by DHPLC in 14 probands. Among them, three were missense mutations, one was a nonsense mutation. Other single nucleotide changes included five single nucleotide polymorphisms, two intron single nucleotide changes, one synonymous mutation. hMLH1 EXON19 CODON749 TAC-->TAG (Tyr-->X), hMSH2 EXON12 CODON629 CAA-->CGA (Gln-->Arg) and hMSH2 EXON15 CODON839 CAT-->CGT (His-->Arg) were new discovered mutations. CONCLUSIONS: (1) DHPLC was considered to be highly effective, convenient technique with consistent results for the mutation detection of hMLH1 and hMSH2 genes. (2) Valid mutations of hMLH1 and hMSH2 genes were identified in about one-third HNPCC kindreds fulfilling Chinese HNPCC criteria and missense mutation was the most common mutational types in this cohort of families.

Adaptor Proteins, Signal Transducing↗

PubMed2005

[Effects of Anxin Granules on blood lipid and ultrastructure of aorta in rabbits with dyslipidemia].

OBJECTIVE: To study the effects of Anxin Granules on dyslipidemia in rabbits caused by high fat plus high cholesterol diet. METHODS: Thirty-two healthy New Zealand male white rabbits were randomly divided into 4 groups: normal control group, untreated group, Zhibituo Tablet-treated group and Anxin Granule-treated group. Rabbits in the normal control group were fed with regular chow, while rabbits in the other three groups were fed with high fat plus high cholesterol diet. Zhibituo Tablets and Anxin Granules were administered to the rabbits in Zhibituo Tablet-treated group and Anxin Granule-treated group at a daily oral dose respectively. At the end of the 10th week, the levels of serum total cholesterol (TC), triglycerides (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), apolipoprotein A(1) (ApoA1) and apolipoprotein B (ApoB) were tested in each group, and the ultrastructures of the aorta were also observed by an electron microscope. RESULTS: Anxin Granules could reduce the levels of TC, TG, LDL-C and ApoB. The results observed by electron microscope showed that, as compared with the untreated group and the Zhibituo Tablet-treated group, the atherosclerosis of aorta in the Anxin Granule-treated group was lighter. And it was found that there were few lipid droplet vacuoles in cytoplasm of the endothelial cells, and various cell organs and elastic membrane were existed, but no lipid droplet vacuoles in cytoplasm of the medial smooth muscle cells. CONCLUSION: Anxin Granules can regulate the metabolism of blood lipid and inhibit the formation of atherosclerosis caused by hyperlipidemia in rabbits.

Animals↗

PubMed2005

[Large genomic deletions of mismatch repair genes in Chinese patients with hereditary nonpolyposis colorectal cancer].

OBJECTIVE: To gain an insight into large genomic deletions in mismatch repair genes MSH2 and MLH1 in Chinese hereditary nonpolyposis colorectal cancer (HNPCC) patients in order to improve genetic detections of HNPCC kindreds. METHODS: Fourteen peripheral blood DNA samples were obtained from 14 unrelated HNPCC patients, and fluorescent labeled quantitative multiplex PCR was used to detect large genomic deletions in MSH2 and MLH1 genes. RESULTS: One of the fourteen probands, a man, was found to have MSH2 exon 1-7 deletions. His cancer-distressed son was also found to have the mutations. Additionally, three normal members of the family had the same mutations. CONCLUSION: Large genomic deletions which mainly present to MSH2 account for 20% of general pathological sequence changes of MSH2 and MLH1 genes in Chinese HNPCC patients, and large genomic detections of mismatch repair genes should be included in the regular genetic detections of Chinese HNPCC kindreds.

Adaptor Proteins, Signal Transducing↗

PubMed2005

[Serum levels and clinical values of soluble intercellular adhesion molecule-1 in patients with nasal polyps].

OBJECTIVE: To assess the role of soluble intercellular adhesion molecule-1 (sICAM-1) in etiology of nasal polyps. METHOD: Twenty-nine patients with nasal polyps and 20 healthy control cases were chosen. Their serum sICAM-1 was determined by a sandwich enzyme-linked immunosorbent assay (ELISA). All patients were treated by glucocorticoid, serum sICAM-1 was determined post-treatment again. RESULT: (1) Serum levels of sICAM-1 in patients with nasal polyps were higher than that of control group: (2) Serum levels of sICAM-1 in patients were reduced after glucocorticoid treatment, the decrease of sICAM-1 was more apparent in evident-effect group than in effect group; (3) There was a close correlation between the decrease of polyp-size scores and the decrease of serum sICAM-1. CONCLUSION: The elevated expressions of sICAM-1 in patients with nasal polyps indicate its important role in eosinophil recruitment, which was considered as a representative hallmark for nasal polyps. The sICAM-1 is down-regulated by systemic and topical glucocorticoid treatment and the decrease of sICAM-1 is correlated with clinical effect. To take these lines of evidence together, anti-adhesion therapy may be effective for nasal polyps, serum sICAM-1 levels may be use to monitor the effect of steroid therapy in nasal polyps.

Adolescent↗

PubMed2005

The analysis for identifying large DNA fragment aberrations of MSH2 and MLH1 genes from familial colorectal cancer in China.

OBJECTIVE: To investigate the frequency of large fragment aberrations of MSH2 and MLH1 genes from Chinese colorectal cancer (CRC) patients with family history. METHODS: Sixteen exons of MSH2, nineteen exons of MLH1 and seven DNA sequences from the other genes of the samples were screened and checked by multiplex ligation dependent probe amplification (MLPA). First, the methodology was confirmed by testing the positive and negative control samples. Then, 32 CRC or hereditary nonpolyposis colorectal cancer (HNPCC) patients with family history and 20 cases of sporadic CRC were applied to investigate for the large fragment aberrations of MSH2 and MLH1 genes. RESULTS: The genomic DNA fragment deletions of all positive controls were identified and verified by MLPA. Three cases of 32 familial (hereditary) CRC/HNPCC were detected and identified to be the germline heterozygous deletions of MSH2 gene, of which exons 1-7 were deleted from patient No.3, exon 11 from No.25 and exons 2-6 from No.11. However, no genomic DNA fragment aberration of either MSH2 or MLH1 gene was uncovered from 20 sporadic CRC. CONCLUSION: Large DNA fragment aberrations of MSH2 gene was a frequent cause of Chinese HNPCC and CRC patients with family history, and the identification of those aberrations should be included in the regular genetic analysis for CRC/HNPCC patients.

Adaptor Proteins, Signal Transducing↗

PubMed2004

The interaction of Schwann cells with chitosan membranes and fibers in vitro.

The bridging of nerve gaps is still one of the major problems in peripheral nerve regeneration. A promising alternative for the repair of peripheral nerve injuries is the bioartificial nerve graft, comprised of a biomaterial pre-seeded with Schwann cells (SCs), which is an effective substrate for enhancing nerve regeneration. Interaction between cultured SCs and biomaterials is of importance. For the purposes of this study, culture systems of normal SCs were used. The biocompatibility of chitosan, including chitosan membranes and chitosan fibers, was evaluated in vitro. The growth of SCs was observed by light and scanning electron microscopy at regular intervals. SCs were identified by immunocytochemical staining and the viability of SCs was measured by MTT assay. The experimental results indicated that SCs could grow onto chitosan materials with two different shapes: spherical and long olivary. They contacted with the extensions. The long olivary cells inclined to encircle chitosan fibers up. It was also found that the cells on the chitosan fibers migrated faster than those on the chitosan membranes. There was a good biological compatibility between chitosan and SCs. Compared with the chitosan membranes, SCs migrated more easily onto the stereoframe of chitosan fibers. These studies contribute information necessary to enhancing our understanding of biocompatibility of chitosan.

Animals↗

PubMed2004

Genetic characterization of Chinese hereditary non-polyposis colorectal cancer by DHPLC and multiplex PCR.

BACKGROUND: Hereditary non-polyposis colorectal cancer (HNPCC) is an autosomal dominant disease due to germline mutations of human mismatch repair genes, mainly hMLH1 and hMSH2. The aim of the present study was to identify the point mutations and large genomic deletions of hMLH1 and hMSH2 genes in 14 Chinese HNPCC families. METHODS: Fourteen families fulfilling the Chinese HNPCC criteria were involved in this study. Genomic DNA isolated from peripheral blood samples was analyzed. Point mutations were detected by denaturing high performance liquid chromatography (DHPLC) followed by DNA sequencing. Multiplex polymerase chain reaction and GeneScan analysis were employed to detect the large genomic deletions of these two genes. RESULTS: Four of the 14 probands (29%) had sequence abnormalities that probably affect the protein function in the exonic regions of hMLH1 and hMSH2 genes. Included were one complete deletion of exons 1-7 and one missense mutation of the hMSH2 gene, and one nonsense mutation and one missense mutation of the hMLH1 gene. The large genomic deletion accounted for 25% (one out of four) of all mutations. Half (two out of four, 50%) of the mutations were missense mutation. In addition, one silent mutation, four polymorphisms in the exonic regions and four polymorphisms in the intronic regions were also discovered. CONCLUSIONS: Point mutations and large genomic deletions of the hMLH1 and hMSH2 genes were responsible for nearly one-third of Chinese HNPCC families. Detection of large genomic deletions should be involved in the routine screening manual for HNPCC families.

Adaptor Proteins, Signal Transducing↗

PubMed2004

[Hypermethylation of hMLH1 promoter in sporadic colorectal cancer].

OBJECTIVE: To identify CpG island hypermethylation of 5'region of hMLH1 promotor and to explore its relationship to microsatellite instability(MSI)in sporadic colorectal carcinoma. METHODS: Forty-one pairs of tissue specimens (normal and cancer) were collected from 41 patients with colorectal cancer. Hypermethylation of hMLH1 promoter was detected by methylation specific PCR; the relationship between methylation and clinicopathological features was analyzed. Combined with BAT25 and BAT26, the MSI status was detected using an automated fluorescent DNA sequencer. RESULTS: Hypermethylation of hMLH1 promoter was detected in 75.6 % (31/41) of samples. Mean age of unmethylation cases (49.2 y) was significantly younger than that of methylation cases (63.6 y) (P<0.05), but there were no differences between two groups in other clinicopathological features. MSI was detected in 43.9 % samples (18/41); hypermethylation of hMLH1 promoter was detected in 94.4 % (17/18) of MSI(+) samples, which was higher than that in MSI(-) samples (60.9 %,14/23, P<0.05). CONCLUSION: Age-related hypermethylation is generally found in patients with sporadic colorectal cancers, which may cause MSI and might be the mechanism in the development of colorectal cancer of elderly people.

Adaptor Proteins, Signal Transducing↗

PubMed2004

[Clinical features and mutation analysis of a poly-(A)8 tract in M3 cholinergic receptor gene in Chinese HNPCC families].

OBJECTIVE: To characterize the clinical features of Chinese HNPCC families and to screen the mutations of a poly-(A)8 tract in M3 cholinergic receptor gene in these families. METHODS: The clinical features of 15 Chinese HNPCC families were characterized. Genomic DNAs from 15 probands were prepared. PCR and direct DNA sequencing analysis were employed to examine the mutations of a poly-(A)8 tract in exon 8 of M3 cholinergic receptor gene. RESULTS: Total 55 cancer patients were found in 15 families including 41 cases of colorectal carcinoma with an average of 2.73 colorectal carcinomas developed per family. Thirty out of forty-one (73%) patients were diagnosed before age of 50 years. Proximal colon was involved in 51% of patients, while anus and rectum were 40 %. Synchronous and metachronous multiple colorectal cancers developed in 5 patients (12%). Two thirds of families belonged to Lynch II syndrome, and total 18 extracolonic malignancies in 14 patients were identified. Gastric carcinoma was the most common extracolonic types. In 15 HNPCC probands, no mutation was detected in the poly-(A)8 tract of exon 8 of M3 cholinergic receptor gene. CONCLUSION: M3 cholinergic receptor gene might have little relation with HNPCC in Chinese population. The criteria for Chinese HNPCC are useful and practical in clinical application.

Adult↗