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Mao-de Lai

Publications and source records attributed to Mao-de Lai.

At least 19 recordsLinked to original sources
PubMed2006

IGFBP7 plays a potential tumor suppressor role against colorectal carcinogenesis with its expression associated with DNA hypomethylation of exon 1.

Insulin-like growth factor binding-protein-7 (IGFBP7) was obtained from our previous colonic adenocarcinoma (CRC) and normal mucosa suppression subtraction hybridization (SSH) cDNA libraries. By RT-PCR and immunohistochemistry, we found that IGFBP7 was overexpressed in CRC tissue compared to normal tissue. However, our in vitro experiments performed in 10 CRC cell lines showed that IGFBP7 expressed only in SW480 and Caco2 cell lines, which implied an underlying reversible regulatory mechanism. Using methylation-specific PCR (MSP) and bisulfite sodium PCR (BSP), we found that its expression was associated with DNA hypomethylation of exon1. This was further supported by the in vitro study which showed restored IGFBP7 expression after demethylation agent 5-aza-2'-deoxycytidine treatment. Correlation analysis between IGFBP7 expression and prognosis indicated that overexpression of IGFBP7 in CRC tissue correlated with favourable survival. Investigation of the functional role of IGFBP7 through transfection studies showed that IGFBP7 protein could inhibit growth rate, decrease colony formation activity, and induce apoptosis in RKO and SW620 cells, suggesting it a potential tumor suppressor protein in colorectal carcinogenesis. In conclusion, our study clearly demonstrated that IGFBP7 plays a potential tumor suppressor role against colorectal carcinogenesis and its expression is associated with DNA hypomethylation of exon 1.

Adenocarcinoma↗
PubMed2006

Anticancer effects of Chinese herbal medicine, science or myth?

Currently there is considerable interest among oncologists to find anticancer drugs in Chinese herbal medicine (CHM). In the past, clinical data showed that some herbs possessed anticancer properties, but western scientists have doubted the scientific validity of CHM due to the lack of scientific evidence from their perspective. Recently there have been encouraging results, from a western perspective, in the cancer research field regarding the anticancer effects of CHM. Experiments showed that CHM played its anticancer role by inducing apoptosis and differentiation, enhancing the immune system, inhibiting angiogenesis, reversing multidrug resistance (MDR), etc. Clinical trials demonstrated that CHM could improve survival, increase tumor response, improve quality of life, or reduce chemotherapy toxicity, although much remained to be determined regarding the objective effects of CHM in human in the context of clinical trials. Interestingly, both laboratory experiments and clinical trials have demonstrated that when combined with chemotherapy, CHM could raise the efficacy level and lower toxic reactions. These facts raised the feasibility of the combination of herbal medicines and chemotherapy, although much remained to be investigated in this area.

Antineoplastic Agents, Phytogenic↗
PubMed2006

[Influence of clinical and pathomorphological parameters on prognosis in colon carcinoma and rectal carcinoma].

OBJECTIVE: To investigate the effects of clinical and pathomorphological parameters on the prognosis of colon carcinoma and rectal carcinoma. METHODS: Univariate and multivariate COX proportional hazard models were used to study the effects of the clinical and pathomorphological factors on the prognosis in 101 cases of colon carcinoma, 219 of rectal carcinoma and 137 of rectal carcinoma under curative resections. RESULT: By using univariate analysis, we identified that lymph node metastasis and distant metastasis were the common prognostic factors for both colon carcinoma and rectal carcinoma. Smoking, deep infiltration, chemotherapy and serum albumin concentration were the uncertain prognostic factors for colon carcinoma. Signet-ring cell carcinoma, larger tumor size (>6 cm), deep infiltration, lack of radical surgery, and advanced TNM stage were the exclusive adverse prognostic factors for rectal carcinoma. Further studies showed that the adverse prognostic factors for the rectal carcinoma under curative resection included deep infiltration, lymph node metastasis, vessel invasion, less of peritumoral lymphocyte infiltration, lack of Crohn's like reactivity, high level of tumor budding, advanced TNM stage and positive urine glucose. By using multivariate analysis based on a COX proportional hazard model, it was identified that smoking, lymph node metastasis and serum albumin concentration were independent prognostic factors for colon carcinoma; advanced TNM stage, distant metastasis and palliative surgery for rectal carcinoma; and vessel invasion, lymph node metastasis and urine glucose for rectal carcinoma under curative resections. CONCLUSION: The various clinical and pathomorphological parameters show different prognostic value for colon carcinoma, rectal carcinoma and rectal carcinoma under curative resections.

Adult↗
PubMed2006

[VNTR polymorphism of C6orf37 in Chinese population].

OBJECTIVE: To identify a novel VNTR in C6orf37 and to detect the C6orf37 VNTR polymorphism distribution in Chinese population. METHODS: RT-PCR and sequencing were conducted to identify VNTR alleles in the variable region of C6orf37.SSLP and DHPLC were applied in detecting the VNTR genotypes in 166 Chinese individuals. RESULT: A novel VNTR sequence was found in the second exon of C6orf37, which was composed of 15 base pairs encoding 5-amino-acid (G-G-D-F-G). The repeat times ranged from 3 to 5. There were three common alleles containing three repeats (a), four repeats (b) and five repeats (c), respectively, which produced three homozygotes (a/a, b/b and c/c) and three heterozygotes (a/b, a/c and b/c). The frequency of a, b, c alleles were 0.145, 0.304, 0.551, respectively in Chinese population. Heterozygosity (H) was 0.583. Polymorphism information content (PIC) was 0.510. The screened result of DHPLC was consistent with that of SSLP. CONCLUSION: A novel highly polymorphic VNTR in C6orf37 exists in Chinese population. DHPLC is the most efficient technique for screening VNTR polymorphism.

Asian People↗
PubMed2006

[The correlation between polymorphisms of matrix metalloproteinase-2 and -9 genes and colorectal cancer of Chinese patients].

OBJECTIVE: To investigate whether the polymorphisms of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) promoters contribute to the development and progression of colorectal cancer in Chinese population. METHODS: the PCR-based denaturing high-performance liquid chromatography or PCR-restriction fragment length polymorphism technique respectively was applied to analyze the MMP-2 -1306C/T and MMP-9 -1562C/T polymorphisms in normal group (126 individuals) and colorectal cancer group (126 cases). Genotype frequencies were compared between patients and matched controls, and the association of genotypes with clinical-pathological parameters was studied. RESULTS: The frequency of the CC genotype in the MMP-2 gene polymorphism was significantly increased in colorectal cancer patients when compared with controls (P<0.05), and individuals with the CC genotype had an increased risk of developing colorectal cancer compared to those with CT+TT genotypes (OR: 1.959; 95%CI: 1.055-3.637). Significant correlation was found between the depth of tumor invasion and MMP-2 -1306C/T polymorphism in colorectal cancer patients. However, the genotype frequencies of MMP-9 -1562C/T in colorectal cancer patients were similar to those in control subjects. CONCLUSION: Our results indicate that MMP-2 -1306 C/T polymorphism may be associated with genetic susceptibility to colorectal cancer and the invasive capability of colorectal cancer in Chinese patients. And it is easier for the CC genotype cancer to invade through bowel wall.

Adult↗
PubMed2005

[Germline polymorphisms of Bat26 and its significance in gastric cancer microsatellite instability].

OBJECTIVE: To detect the germline polymorphic variations of Bat26 in Chinese and its significance in microsatellite instability (MSI) study of gastric cancers. METHODS: Bat26 was analyzed by PCR-based denatured polyacrymide gel electrophoresis-silver stain method in peripheral blood from 389 healthy people and 34 gastric cancers with matched normal mucosa. Eleven other microsatellite loci were also detected for gastric cancers. RESULT: (1) No Bat26 variations were identified in 423 genomic DNA from peripheral blood or normal mucosa by polyacrymide gel electrophoresis. (2) Two MSI-H cancers, oth Bat26+, were detected in 34 cases of gastric cancer. The alterations of Bat26 and MSI-H status were identical (P<0.05). (3) Compared with those of RER-cancers, MSI-H (RER+)cancers showed more obvious infiltration of intraepithelial lymphocytes and peri-tumoral lymphocytes, and more pushing borders (P<0.05). CONCLUSION: (1) The germline polymorphisms of Bat26 in Chinese people are quasimonomorphic. Thus, no matched genomic DNA is needed while Bat26 was selected for tumor MSI analysis. (2) Bat26 is an independent indicator of MSI-H gastric cancers with distinct clinicopathological features.

Chromosomal Instability↗
PubMed2005

[Correlation of multiple primary lung cancer with bronchial and alveolar epithelial dysplasia].

OBJECTIVE: To investigate the correlation of multiple primary lung cancer with bronchial epithelial dysplasia and atypical adenomatous hyperplasia of bronchiolo-alveolar epithelium. METHODS: Careful pathological examinations were performed on 114 surgical specimens of primary lung carcinoma. The correlation of multiple primary lung cancer with bronchial epithelial dysplasia and atypical adenomatous hyperplasia of bronchiolo-alveolar epithelium was analyzed. RESULTS: Of 114 cases of primary lung cancer,13 cases of multiple primary lung cancer (11.4 %) was identifiedìwhich consisted of 6 cases containing two primary bronchogenic carcinoma and 7 containing one bronchogenic carcinoma and one bronchiolo-alveolar carcinoma. The rate of multiple primary lung cancers was significantly higher in individuals with high grade bronchial epithelial dysplasia than in those with low grade dysplasia (r=0.238, P<0.05). CONCLUSION: Bronchial and alveolar epithelial cells may develop malignancy synchronously or metachronously. The probability of developing multiple primary lung cancer will increase in the lungs with extensive and severe bronchial epithelial dysplasia.

Adenocarcinoma↗
PubMed2005

[Study on independent factors on the prognosis of colorectal carcinoma: TNM stage, tumor budding, perineural invasion, peritumoral-lymphocytic infiltration and urine glucose].

OBJECTIVE: To study the influence of clinical and pathological-morphological parameters on the prognosis of colorectal carcinoma. METHODS: Univariate and multivariate Cox proportional hazard model were used to study the influence of clinical and pathological-morphological factors on the prognosis in 226 colorectal carcinoma cases. RESULTS: Using univariate analysis, data showed that the factors significantly related to disease prognosis would include: the depth of direct spread, vessel invasion, perineural invasion, tumor budding, peritumoral-lymphocytic infiltration, Crohn-like reaction, number of positive lymph nodes, distant metastasis, TNM stage and urine glucose. Multivariate Cox proportional hazard model showed that six factors were identified to be associated with higher relative-risk (RR), including: older age, advanced TNM stage, more severe budding, perineural invasion, less peritumoral-lymphocytic infiltration and urine glucose. CONCLUSION: Age, TNM stage, tumor budding, perineural invasive, peritumoral-lymphocytic infiltration and urine glucose were independent predictors to the prognosis of colorectal carcinoma.

Aged↗
PubMed2005

[Diagnostic accuracy and pitfalls in fine needle aspiration cytology of salivary glands: a study of 113 cases].

OBJECTIVE: To describe the fine needle aspiration cytology (FNAC) features of various salivary gland lesions and to analyze the respective diagnostic value and pitfalls. METHODS: 113 FNAC specimens of salivary gland lesions were reviewed and correlated with clinical and histopathologic findings. RESULTS: The FNAC diagnostic failure (2); non-neoplastic lesions (12); benign neoplasm (82) and malignant neoplasm (17). Cytologically, the distinction between cellular pleomorphic adenoma, adenoid cystic carcinoma and basal cell adenoma could be difficult due to their overlapping morphologic features. The cytologic patterns of primary lymphoepithelial carcinoma of the parotid were indistinguishable from those of metastatic nasopharyngeal undifferentiated carcinoma. The ultimate distinction relied on clinical correlation. The three inaccurately diagnosed cases of FNAC are, as follows: reactive lymphoid hyperplasia of lymph node mistaken as non-Hodgkin lymphoma, mucoepidermoid carcinoma diagnosed as "scanty atypical cells present" and primary lymphoepithelial carcinoma mistaken as benign lymphoepithelial lesion. On the basis of FNAC, 97.4% (110 /113) were correctly depicted as benign (95/96; 99.0%) or malignant (15/17; 88.2%). Furthermore, 90.3% (102 /113) (specificity = 91.9%; 102/111) were accurately diagnosed, including 91.7% (88/96) benign lesions (specificity = 92.6% ; 88/95) and 82.4% (14/17) malignant tumors (specificity = 87.5%; 14/16). CONCLUSIONS: FNAC is reliable in distinguishing benign and malignant salivary gland lesions. A specific cytologic diagnosis is often possible. On the other hand, due to the pitfalls in cytologic diagnosis of certain salivary gland tumors, tissue biopsy for histologic examination may be necessary.

Adenolymphoma↗
PubMed2004

[Bioinformatics analysis to the differentially expressed genes of normal mucosa and carcinoma of colon].

OBJECTIVE: To systemically analyze the differentially expressed genes from normal mucosa and carcinoma of colon obtained by SSH method. METHODS: An automatic platform for the analysis of nucleotides based on Linux was constructed, and one of the three subtracted libraries from SSH (T -N) was systematically analyzed by this platform. Part of the results was verified by semi- quantity RT-PCR. RESULT: The automatic platform for the analysis of nucleotides based on Linux was successfully constructed. There were 15 contigs from the subtracted T-N libraries, among which 2 had no match with known genes in the GenBank. The expressions of genes Homo Sapiens thymosin beta 4 (THY) and Homo Sapiens HbxAg transactivated protein 2 (XTP) had trends of increase with the progress of normal tissue-adenoma-adenocarcinoma when verified by semi- quantity RT-PCR. CONCLUSION: Linux-based automatic platform provides an efficient way to systematically analyze the nucleotide sequences, which may be used in study on the mechanism of colorectal carcinogenesis.

Colon↗
PubMed2004

[Structural features of GR6 gene and its expression in colorectal neoplasm].

OBJECTIVE: To determine the characteristics of GR6 gene and putative GR6 protein, and to evaluate the expression of GR6 gene in colorectal cancer and normal mucosa. METHODS: Bioinformatic software and databases were applied to analyze the characteristics of GR6 gene and putative GR6 protein. Semi-quantitative RT-PCR was used to detect the expression of GR6 gene in colorectal carcinoma, adenoma and normal mucosa. RESULT: GR6 gene, encoding putative GR6 protein, consisted of 3 exons and contained 4 CpG islands by sequence analysis. It was predicted that putative GR6 protein included one protein kinase C phosphorylation site, one casein kinase II phosphorylation site, and three N-myristoylation sites. PSORT II software analysis predicted that putative GR6 protein was located in nucleus (reliability: 76.7%). At the level of mRNA, the expression of GR6 gene was high in normal mucosa, moderate in mucosa adjacent to cancer and adenoma tissue, low in colorectal carcinoma tissue. Significant differences were demonstrated between normal mucosa and adenoma (P<0.05), normal mucosa and carcinoma (P<0.01). CONCLUSION: The putative GR6 protein, encoded by GR6 gene may predictably function as an important nuclear signal transduction molecule. Decreased expression of GR6 gene may play an important role in the initiation and promotion of colorectal neoplasia.

Amino Acid Sequence↗
PubMed2004

[Alterations of p53 gene and microsatellite instability in ulcerative colitis and ulcerative colitis-associated colorectal cancer].

OBJECTIVE: To study the expression of p53 protein, incidence of p53 gene mutation and microsatellite instability in ulcerative colitis, dysplasia of colonic mucosa and ulcerative colitis-associated colorectal cancer. METHODS: P53 protein expression was detected by immunohistochemistry in 70 specimens from 21 cases of ulcerative colitis and 25 colonic mucosa specimens from normal subjects. The specimens of ulcerative colitis were examined for the mutation in exon 5, 6, 7, 8 of p53 gene with microdissection-PCR-SSCP/HA-clone-sequencing technique and the alterations in 10 microsatellite loci with microdissection-PCR-SSLP-clone- sequencing technique. RESULT: None of 25 normal specimens was p53-positive immunohistochemically, while 4/21 of ulcerative colitis specimens were p53-positive. P53- positive rate in inflammatory mucosa of ulcerative colitis specimens was 0/5, while that was 1/7, 2/7 and 1/2 in low-grade displasia (LGD), high-grade displasia (HGD) and carcinoma, respectively. The abnormal exons were detected by SSCP and confirmed by sequencing in 2 out of 21 cases: one was exon 6 in a case with carcinoma and the other was exon 8 in a HGD case; both had positive P53 expression. Two cases showed positive in Bat26 locus by SSLP: one was a LGD case, the other was a case of carcinoma, who also had abnormal exon 6 of p53 gene. Other 9 microsatellite loci, (TGF beta RII(A)(10), IGFIIR(G)(8), IGFIIR(CT)(5), TGF beta RII(GT)(3), BAX(G)(8), hMSH3(A)8, hMSH6(C)(8), TCF4(A)(9) and DPC4 (CA)(17)) were showed negative in all cases. CONCLUSION: P53 gene mutations and microsatellite instability may be one of the mechanisms for higher risk of carcinogenesis in ulcerative colitis.

Adolescent↗
PubMed2004

[A possible preneoplastic lesion of colorectum].

OBJECTIVE: To investigate KiA10 expression in colorectal cancer and related colorectal tissues. METHODS: KiA10 expression was detected by immunohistochemistry in tissue specimens from 101 cases of colorectal cancer and matched cut-margin mucosa and mucosa adjacent to cancers; also in colorectal specimens from 16 cases of ulcerative colitis, 16 of Crohn's disease and 3 healthy subjects. RESULT: The positive rate of KiA10 expression in colorectal cancer was 14.85% (15/101); KiA10 positive crypts was demonstrated in 18 cut-margin mucosa and 18 mucosa adjacent to tumors respectively, but they were not matched with each other. CONCLUSION: The results suggest that KiA10-positive crypts of the colon might be a preneoplastic lesion.

Adult↗