The notch regulator MAML1 interacts with p53 and functions as a coactivator.

Members of the evolutionarily conserved Mastermind (MAM) protein family, including the three related mammalian Mastermind-like (MAML) proteins MAML1-3, function as crucial coactivators of Notch-mediated transcriptional activation. Given the recent evidence of cross-talk between the p53 and Notch signal transduction pathways, we have investigated whether MAML1 may also be a transcriptional coactivator of p53. Indeed, we show here that MAML1 is able to interact with p53.

[Expression and significance of Bmi-1 in breast cancer].

Background & Objective: Bmi-1, a putative oncogene, is a member of the polycomb group genes family. It is widely expressed in many kinds of tumors. This study was to investigate the expression and significance of Bmi-1 in breast cancer.

[Effects of MT1-MMP on the in vitro invasiveness of breast cancer cells].

Objective: To investigate the effect of membrane type-1 matrix metalloproteinase (MTI-MMP) on the invasive potential of breast cancer cell and analyze its mechanisms.

Methods: After treatment of breast cancer MDA-MB-453 cell line with concanavalin A ( ConA, 20 microg/ml) for 24 h, MT1-MMP protein was detected in cancer cells by Western analysis and immunocytochemistry. MDA-MB-453 cells were cultured with exogenous latent proMMP-2 and MMP-2 activity was analyzed by gelatin zymography.

Tetrandrine achieved plasma concentrations capable of reversing MDR in vitro and had no apparent effect on doxorubicin pharmacokinetics in mice.

Purpose: Tetrandrine (Tet), a multidrug resistant (MDR) modulator, was a potential candidate for use in cancer therapy and exhibited potent biological activity in vitro and in vivo when combined with anticancer agents such as doxorubicin, paclitaxel. Our aims were to determine whether serum concentration of Tet, which was capable of blocking P-gp in vitro, could be safely achieved in mice and whether Tet induced pharmacokinetic alterations in serum doxorubicin disposition in mice.

Methods: Tet of 30 mg/kg dose used to reverse MDR was administrated intraperitoneally in mice.

Centromere protein H is a novel prognostic marker for nasopharyngeal carcinoma progression and overall patient survival.

Purpose: The aim of the present study was to analyze the expression of Centromere protein H (CENP-H), one of the fundamental components of the human active kinetochore, in nasopharyngeal carcinoma (NPC) and to correlate it with clinicopathologic data, including patient survival.

Experimental Design: Using reverse transcription-PCR and Western blot, we detected the expression of CENP-H in normal nasopharyngeal epithelial cells, immortalized nasopharyngeal epithelial cell lines, and NPC cell lines. Using immunohistochemistry, we analyzed CENP-H protein expression in 160 clinicopathologically characterized NPC cases.

Functional advantage of NPC-related V-val subtype of Epstein-Barr virus nuclear antigen 1 compared with prototype in epithelial cell line.

Epstein-Barr virus (EBV) is closely associated with nasopharyngeal carcinoma (NPC) and the viral nuclear antigen 1 (EBNA1) plays a crucial role in viral latency. Three EBNA1 subtypes, P-ala, V-thr and V-val have been detected from healthy carriers in Guangzhou area. A close relation of V-val EBNA1 with NPC was suggested by its preference to infect NPC cells.

Infection of Epstein-Barr virus in colorectal cancer in Chinese.

Background & Objective: Except for the tight correlation to nasopharyngeal carcinoma, accumulating evidences show that Epstein-Barr virus (EBV) is correlated to other carcinomas. This study was to investigate the correlation of EBV to colorectal carcinoma in Chinese.

Methods: EBV DNA was detected by polymerase chain reaction (PCR) in 90 specimens of primary colorectal carcinoma and 25 specimens of corresponding adjacent non-cancerous tissue, with the primers covering 2 different regions of EBV genome, BamH I W fragment and latent membrane protein 1 (LMP1) exon 3.

Lgf-YL-9 induces apoptosis in human epidermoid carcinoma KB cells and multidrug resistant KBv200 cells via reactive oxygen species-independent mitochondrial pathway.

Pyrazolon derivatives were reported to have cytotoxicity to some tumour cells. In the present study, we investigated the effect of Lgf-YL-9 on cytotoxicity and cell apoptosis in human epidermoid carcinoma drug-sensitive parental KB cells and multidrug resistant (MDR) KBv200 cells. Lgf-YL-9 exhibited potent cytotoxicity not only to KB cells but also to KBv200 cells, and the IC(50) were 3.

Hypoxia can contribute to the induction of the Epstein-Barr virus (EBV) lytic cycle.

Background: Like other herpes viruses, latent Epstein-Barr virus (EBV) infection can be reactivated to lytic replication. Reactivation can be achieved by treatment with various reagents, including tetradecanoyl phorbol acetate (TPA) and Ca2+ ionophores. Relatively little is known about the physiological factors related to reactivation of EBV.

Bmi-1 is a novel molecular marker of nasopharyngeal carcinoma progression and immortalizes primary human nasopharyngeal epithelial cells.

The Bmi-1 oncoprotein regulates proliferation and oncogenesis in human cells. Its overexpression leads to senescence bypass in human fibroblasts and immortalization of human mammary epithelial cells. In this study, we report that compared with normal nasopharyngeal epithelial cells (NPEC), Bmi-1 is overexpressed in nasopharyngeal carcinoma cell lines.

[Sequence analysis of the CTL epitopes in transmembrane region of latent membrane protein 2 of Epstein-Barr virus derived from nasopharyngeal carcinoma cells].

Background & Objective: Epstein-Barr virus (EBV) in nasopharyngeal carcinoma (NPC) cells expresses Epstein-Barr nuclear antigen 1 (EBNA1), latent membrane protein 1 (LMP1), and LMP2. LMP2 is an ideal target for immunotherapy because LMP2 mRNA is detected in 100% nasopharyngeal carcinoma cells and LMP2 protein shows stronger immunogenity than the rest 2 viral proteins. This study was to analyze the sequence of CTL epitopes in the transmembrane region of LMP2 to optimize LMP2-targeted immunotherapy.

[Expression of key cell cycle markers in squamous cell carcinoma of the cervix positive in human papillomavirus: a comparative study between Chinese and Australian populations].

Objective: To investigate the patterns of expression of key cell cycle proteins targeting on the human papillomavirus (HPV) sites E6 and E7 in cervical carcinoma.

Methods: Semiquantitative immunohistochemistry was used to determine the expression of the cell cycle regulatory factor p53, retinoblastoma gene product pRb, cyclin-dependent kinase inhibitors p21(CIP1/WAF1) (p21), p16(INK4A) (p21), and p27(KIP1) (p21), and cyclin D1 targeting on the HPV sites E6 and E7 in 73 HPV 16-positive specimens of cervical squamous cell carcinoma, 35 from Australia patients and 38 age, lymph node status, and grade of tumor-matched Chinese patients.

Results: There were no significant differences in age, lymph node status, and grade of tumor between the Chinese and Australian groups, however, the number of the patients in advanced stage (>Stage IIa) was greater in the Chinese group than in the Australian group (19:7).

[Establishment of three-dimensional culture models related to different stages of nasopharyngeal carcinogenesis].

Background & Objective: Since three-dimensional culture simulates in vivo microenvironment better than planar culture, the biological character of cells in three-dimensional culture model are more similar with that of living tissues. This study was to establish three-dimensional culture models that represent different stages of nasopharyngeal caicinogenesis, and provide information to elucidate the related molecular events.

Methods: Non-tumor nasopharyngeal biopsy specimens were used to culture for normal nasopharyngeal epithelial cells.

A functional variant in the transcriptional regulatory region of gene LOC344967 cosegregates with disease phenotype in familial nasopharyngeal carcinoma.

Nasopharyngeal carcinoma is a common malignancy in Southeast Asian countries, and genetic background is a well-known component of the complexity underlying its tumorigenic process. We have mapped a nasopharyngeal carcinoma susceptibility locus to chromosome 4p15.1-q12 in a previous linkage study on nasopharyngeal carcinoma pedigrees.

The clinical significance of twist expression in nasopharyngeal carcinoma.

The present study was aimed to determine twist expression in nasopharyngeal carcinoma (NPC) and to investigate the clinicopathological significance in the progress of NPC. Semiquantitative RT-PCR and Western blotting were carried out to investigate the expression of Twist in NPC cell lines and normal nasopharyngeal epithelial cell line, which showed that both Twist mRNA and protein were up-regulated in the tumor cells in comparison with the normal cells. We then examined Twist mRNA expression in non-cancerous nasopharyngeal mucosa (10 cases) and NPC (95 cases) using in situ hybridization.

Genomic sequence analysis of Epstein-Barr virus strain GD1 from a nasopharyngeal carcinoma patient.

To date, the only entire Epstein-Barr virus (EBV) genomic sequence available in the database is the prototype B95.8, which was derived from an individual with infectious mononucleosis. A causative link between EBV and nasopharyngeal carcinoma (NPC), a disease with a distinctly high incidence in southern China, has been widely investigated.

Expression of chemokine receptor CXCR4 in nasopharyngeal carcinoma: pattern of expression and correlation with clinical outcome.

Nasopharyngeal carcinoma (NPC) is a tumor derived from epithelial cells and Epstein-Barr virus infection has been reported to be a cause of this disease. Chemokine receptor CXCR4 was found to be involved in HIV infection and was highly expressed in human malignant breast tumors and the ligand for CXCR4, CXCL12 (SDF-1), exhibited high expression in organs in which breast cancer metastases are often found. The metastatic pattern of NPC is quite similar to that of malignant breast tumors.