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Weiliu Qiu

Publications and source records attributed to Weiliu Qiu.

11 recordsLinked to original sources

Identification of genes associated with cisplatin resistance in human oral squamous cell carcinoma cell line.

BACKGROUND: Cisplatin is widely used for chemotherapy of head and neck squamous cell carcinoma. However, details of the molecular mechanism responsible for cisplatin resistance are still unclear. The aim of this study was to identify the expression of genes related to cisplatin resistance in oral squamous cell carcinoma cells. METHODS: A cisplatin-resistant cell line, Tca/cisplatin, was established from a cisplatin-sensitive cell line, Tca8113, which was derived from moderately-differentiated tongue squamous cell carcinoma. Global gene expression in this resistant cell line and its sensitive parent cell line was analyzed using Affymetrix HG-U95Av2 microarrays. Candidate genes involved in DNA repair, the MAP pathway and cell cycle regulation were chosen to validate the microarray analysis results. Cell cycle distribution and apoptosis following cisplatin exposure were also investigated. RESULTS: Cisplatin resistance in Tca/cisplatin cells was stable for two years in cisplatin-free culture medium. The IC50 for cisplatin in Tca/cisplatin was 6.5-fold higher than that in Tca8113. Microarray analysis identified 38 genes that were up-regulated and 25 that were down-regulated in this cell line. Some were novel candidates, while others are involved in well-characterized mechanisms that could be relevant to cisplatin resistance, such as RECQL for DNA repair and MAP2K6 in the MAP pathway; all the genes were further validated by Real-time PCR. The cell cycle-regulated genes CCND1 and CCND3 were involved in cisplatin resistance; 24-hour exposure to 10 microM cisplatin induced a marked S phase block in Tca/cisplatin cells but not in Tca8113 cells. CONCLUSION: The Tca8113 cell line and its stable drug-resistant variant Tca/cisplatin provided a useful model for identifying candidate genes responsible for the mechanism of cisplatin resistance in oral squamous cell carcinoma. Our data provide a useful basis for screening candidate targets for early diagnosis and further intervention in cisplatin resistance.

Carcinoma, Squamous Cell↗

[Recent development of reparative and reconstructive surgery on oral and maxillofacial regions].

OBJECTIVE: To summarize the latest development of the oral and maxillofacial reparative and reconstructive surgery. METHODS: The literature at home and abroad was reviewed and the main creative concepts in this field were summarized and analyzed. RESULTS: In the terms of the oral and maxillofacial reparative and reconstructive surgery, the significant achievements were made in the following aspects: transplantation of revascularized tissues, artificial materials, platelet-rich plasma, distraction osteogenesis, microsurgery on fracture, arthroplasty, dynamic repair, and computer-assisted design. CONCLUSION: Based on the previous achievements, the oral and maxillofacial reparative and reconstructive surgery will have a further development, especially in the individualized treatment.

Humans↗

[Repair and reconstruction of oral and maxillofacial defect--clinical analysis of 1973 cases].

OBJECTIVE: To compare the reconstructive method of oral and maxillofacial defect with free tissue flaps. METHODS: The clinical materials were collected from 1 973 reconstructive cases between January 2000 and June 2004 and analyzed in terms of the distribution of age, gender, disease type, defect location, reconstructive method and the incidence of vascular crisis of free flaps as well as success rate of free flap respectively. SAS 6. 12 was adopted for statistical analysis. RESULTS: A total of 1973 reconstructive cases included 764 in middle age (>45 years to < or =60 years, 38.72%), 527 in old age (>60 years, 26.71%), 450 young adults (>28 years to < or =45 years, 22.81%), 187 in young age (>14 years to < or =28 years, 9.48%) and 45 children (< or =14 years, 2.28%). The ratio of male to female was 1.5 : 1. The ratio of benign to malignancy lesion was 1 : 1.94. The tongue defect accounted for 20.63%, followed by mandibular defect(17.38%), parotid defect(13.74%), buccal defect(12.72%), maxillary defect (8.16%), oral pharynx defect (7.60%), floor of mouth defect (5.68%) and others (14.09%). Vascular free flap transfers accounted for 45.82%(904), followed by axial flap(38.17%, 753), random flap (10.19%, 201), a vascularized bone graft (1.52%, 30) and others(4.30%, 85). The most frequently used flap was the forearm flap(594 cases), followed by the fibula free flap(143 cases) and the pedicled pectoralis major myocutaneous flap(369 cases); these three flaps accounted for 56.06% (1106/1973). In 47 free tissue flaps (5.20%) having vascular crisis, 30 were saved (63.83%). The success rate of total free tissue flaps was 98.19% (923/940). CONCLUSION: The majority of reconstructive cases of oral and maxillofacial defects is the middle aged and the old aged male patients with malignancy. The tongue defect accounts for about one fifth of all the cases. The vascularized free flap has a high success rate, so it is a main method for reconstruction of oral and maxillofacial defects. The forearm flap, the fibular free flap and the pedicled pectoralis major myocutaneous flap are the main management for repairing oral and maxillofacial defects.

Adolescent↗

Different cDNA microarray patterns of gene expression reflecting changes during metastatic progression in adenoid cystic carcinoma.

BACKGROUND: The metastatic ability of tumor cells is determined by level of expression of specific genes that may be identified with the aid of cDNA microarray containing thousands of genes and can be used to establish the expression profile of disease related genes in complex biological system. MATERIALS AND METHODS: Salivary adenoid cystic carcinoma cell line and its high metastases adenoid cystic carcinoma clone were used as model systems to reveal the gene expression alteration related to metastasis mechanism by cDNA microarray analysis. The correlation of metastatic phenotypic changes and expression levels of 4 selected genes (encoding CD98, L6, RPL29, and TSH) were further validated by using RT-PCR analysis of human tumor specimens from primary adenoid cystic carcinoma and corresponding metastasis lymph nodes. RESULTS: Of the 7,675 clones of known genes and expressed sequence tags (ESTs) that were analyzed, 30 showed significantly different (minimum 3 fold) expression levels in two cell lines. Out of 30 genes found differentially expressed, 18 were up regulated (with ratio more than 3) and 12 down regulated (with ratio less than 1/3). CONCLUSION: Some of these genes are known to be involved in human tumor antigen, immune surveillance, adhesion, cell signaling pathway and growth control. It is suggested that the microarray in combination with a relevant analysis facilitates rapid and simultaneous identification of multiple genes of interests and in this study it provided a profound clue to screen candidate targets for early diagnosis and intervention.

Journal Article↗

A cervical lymph node metastatic model of human tongue carcinoma: Serial and orthotopic transplantation of histologically intact patient specimens in nude mice.

PURPOSE: A lymph node metastatic model of human tongue carcinoma using orthotopic and serial transplantation was established in nude mice to study the invasive and metastatic properties of human tongue cancer. MATERIALS AND METHODS: Lymph node metastatic specimens of human tongue carcinoma were transplanted into nude mice orthotopically. Tumors dissected from the metastatic lymph nodes of the nude mice were serially transplanted into tongues of disease-free nude mice at 4-week intervals. RESULTS: All mice developed aggressive and diffuse well-differentiated squamous cell carcinoma at tongue recipient sites. Tumor cells invaded to lymphatic vessels. In addition, increased cervical lymph node metastasis was noted in the first (3 of 14, or 21%), second (4 of 11, or 36%), third (6 of 10, or 60%), or fourth (11 of 14, or 79%) transplantation. In mice, 2 of 14 lung metastases were found in the fourth round of transplantation. CONCLUSION: After surgical specimens of the lymph node metastasis for human tongue cancer were transplanted into the tongue of nude mice, the clinical characteristics of human tongue carcinoma, especially invasion and metastasis, were observed. This metastatic model involving orthotopic and serial transplantation should be useful for studies on the mechanisms, treatment, and prevention of human carcinoma of tongue.

Animals↗

Normal and pathological anatomy of the TMJ viewed by computerized panoramic arthroscopic images.

The individual single images obtained to document TMJ arthroscopy are often difficult to interpret. The aim of this paper is to make available a new computer-aided image process system to reformat the panoramic arthroscopic images of the temporomandibular joint (TMJ). Arthroscopic images were input directly into a computer and memorized into a magneto optical disk. Using Photoshop 5.0 (Adobe Systems, Inc., Mountain View, CA) software for Windows 98 (Microsoft Corp., King County, WA) the images were edited and adjusted to compound sagittal and/or coronal panoramic images of normal articular surfaces as well as pathology of TMJ disorders. Normal TMJ sagittal and coronal two-dimensional composite panoramic arthroscopic images were achieved. The panoramic images of some intracapsular disorders (including disk displacement, osteoarthrosis, adhesion, and disk perforation) were also obtained. The computerized arthroscopic panoramic images are a new technique that may aid in the understanding of TMJ anatomy and TMJ disorders.

Arthrography↗

Craniofacial resection of advanced oral and maxillofacial malignant tumors.

OBJECTIVE: To evaluate the clinical outcome of craniofacial resection for advanced malignant tumors in oral and maxillofacial regions. METHODS: Forty-six patients who underwent craniofacial resection for malignancies involving the anterior and middle cranial fossa over a 20-year period between June 1978 and December 1997 at our department were evaluated. Twenty patients received radiation therapy and an adjuvant therapy after the operation. Eleven patients received chemotherapy of various types as an adjuvant therapy. RESULTS: The 3- and 5-year survival rates were 48.8% (20/41) and 35.1% (13/37), respectively, while the 10-year survival rate was 20% (4/20). CONCLUSIONS: Our results revealed good prospects of using craniofacial resection on patients with advanced malignancies in the oral and maxillofacial regions.

Adolescent↗

Identification of genes with consistent expression alteration pattern in ACC-2 and ACC-M cells by cDNA array.

OBJECTIVE: To investigate the molecular events and metastasis-related genes in ACC-2 and ACC-M cells of adenoid cystic carcinoma. METHODS: Adenoid cystic carcinoma cell line ACC-2 and a sample of adenoic cystic carcinoma cell clones highly metastatic to the lung (ACC-M) were investigated. ACC-2 and ACC-M cells were cultured and collected. Total RNA was extracted using standard Trizol RNA isolation protocol. The poly A mRNA was purified and labeled in reverse transcription using M-MLV reverse transcriptase in the presence of Easytides deoxyadenosin 5' triphosphate [alpha-(33)p]. A cDNA array was assembled with 7675 EST clones which represented the same number of independent single genes. Prepared nylon membranes were hybridized with the [alpha (33)p]-dATP labeled mRNA from ACC-2 and ACC-M cells. Membranes were exposed to phosphor screen. RESULTS: The high-through put analysis of gene expression pattern was obtained from ACC-2 and ACC-M cells by the hybridization of the cDNA array. The difference of parallel gene expression was analyzed. Genes were clustered according to their expression level in the ACC-M compared with ACC-2 cells. According to each gene's ratio of expression level, there were 17 genes which were upregulated with ratios over 3.0, and there were 12 genes which were downregulated with ratios below 0.33 (1/3.0 = 0.33). CONCLUSIONS: Significantly different expression patterns between ACC-2 and ACC-M by cDNA array were observed. The differences lie in signal pathways, tumor antigens, immune molecular and some unknown genes.

Adult↗

Direct-puncture embolization of intraosseous arteriovenous malformation of jaws.

PURPOSE: Our goal was to report our experience with direct-puncture embolization of intraosseous arteriovenous malformations (AVMs). PATIENTS AND METHODS: Three cases of AVM in the mandible and 2 cases of AVM in the maxilla comprised this study group. The patients were embolized with fiber coils through direct puncture, and the coils were placed directly into the center of the intraosseous lesion, in some cases in conjunction with polyvinyl alcohol foam and N-butyl-2-cyanoacrylate through vascular access. RESULTS: The acute arterial bleeding was controllable in 3 patients. The other 2 patients had pericoronal oozing bleeding and a warm soft pulsative mass on the left face, respectively; their symptoms and signs improved greatly. The pericoronal oozing of blood in all patients disappeared during a 3- to 13-month follow-up, and new bone formation was found on the follow-up radiography. CONCLUSIONS: The embolization of the AVM of jaws by direct percutaneous puncture in conjunction with endovascular therapy is effective and safe, but longer follow-up is required to determine the true efficacy of this method of treatment.

Adolescent↗

Comparative study of clinical manifestation, plain-film radiography, and computed tomographic scan in arteriovenous malformations of the jaws.

OBJECTIVE: The purpose of this study was to summarize the clinical manifestation, plain-film radiography, and computed tomographic (CT) scan features of arteriovenous malformations (AVMs) of the jaws on the basis of a series of 12 patients. STUDY DESIGN: This study group comprised twelve patients with AVM of the jaws from February 1996 to February 2001. Seven cases were located in the mandible, and 5 in the maxilla. Both plain-film radiography and CT scan were available for all cases. For the patients with lesions in the mandible, panoramic, posterioanterior, and lateral mandibular views were applied. Waters' position view and panoramic radiography were indicated for AVMs of the maxilla. RESULTS: Each patient with AVM of the maxillary bone had involvement of adjacent soft tissues. Various radiographic signs were noted, including erosion, coarse trabeculae, and apparent lack of any radiographic change, and CT scans featured cystic expansion of alveolar process with broken cortex. The radiographic signs and CT scan features of AVMs in the mandible were related to involvement of surrounding soft tissues. If involvement of the adjacent soft tissues was found, "soap bubble" radiolucency was shown radiographically and osteolytic expansion with perforation of cortex was present on CT scan. In cases without surrounding soft tissue involvement, the various radiographic signs included multilocular or unilocular radiolucency or coarse trabeculae; osteolytic expansions with intact cortex were found on CT scan. CONCLUSION: AVMs of the jaws showed intraosseous osteolytic expansion on CT scan but had variable appearance on plain-film radiographs.

Adolescent↗

Embolization of the AVM of jaws by direct percutaneous puncture combined with endovascular route.

OBJECTIVE: To report our experience to embolize the AVM of jaws by direct puncture in conjunction with endovascular treatment. METHODS: 5 cases of AVM of mandible and 2 cases of AVM of maxilla comprised this study group. The patients were embolized with coils with wool strands and PVA. The coils were placed directly into the center of the intraosseous lesion. The procedure was under the guidance of DSA machine (PHILIPS V3000). RESULTS: The acute arterial bleeding of 4 patients was controllable. The chronic oozing bleeding in the other 3 cases disappeared in the 3 - 24 months follow-up and new bone formation was found in the follow-up radiography. CONCLUSIONS: The embolization of the AVM of jaws by direct puncture in conjunction with endovascular therapy is effective and safe, however the longer follow-up is expected.

Adolescent↗