Downregulation of iASPP Expression Suppresses Proliferation, Invasion and Increases Chemosensitivity to Paclitaxel of Head and Neck Squamous Cell Carcinoma / 中国医学科学杂志(英文版)

Objective Our previous study has revealed that iASPP is elevated in human head and neck squamous cell carcinoma (HNSCC) and iASPP overexpression signifcantly correlates with tumor malignant progression and poor survival of HNSCC. This study investigated the function of iASPP playing in proliferation and invasion of HNSCC . Methods HNSCC cell line Tu686 transfected with Lentiviral vector-mediated iASPP-specific shRNA and control shRNA were named the shRNA-iASPP group and shRNA-NC group, respectively. The non-infected Tu686 cells were named the CON group. CCK-8 assay, flow cytometry, transwell invasion assay were performed to detect the effects of iASPP inhibition . Results Our results demonstrated that the proliferation of shRNA-iASPP cells at the time of 72 h (=32.459, =0.000), 96 h (=51.407, =0.000), 120 h (=35.125, =0.000) post-transfection, was significantly lower than that of shRNA-NC cells and CON cells. The apoptosis ratio of shRNA-iASPP cells was 9.42% ± 0.39% (=299.490, =0.000), which was significantly higher than that of CON cells (2.80% ± 0.42%) and shRNA-NC cells (3.18% ± 0.28%). The percentage of shRNA-iASPP cells in G0/G1 phase was 74.65% ± 1.09% (=388.901, =0.000), which was strikingly increased, compared with that of CON cells (55.19% ± 1.02%) and shRNA-NC cells (54.62% ± 0.88%). The number of invading cells was 56 ± 4 in the shRNA-iASPP group (=84.965, =0.000), which decreased significantly, compared with the CON group (111 ± 3) and the shRNA-NC group (105 ± 8). The survival rate of shRNA-iASPP cells administrated with paclitaxel was highly decreased, compared with CON cells and shRNA-NC cells (=634.841, =0.000). Conclusion These results suggest iASPP may play an important role in progression and aggressive behavior of HNSCC and may be an efficient chemotherapeutic target for the treatment of HNSCC.

Resection of parapharyngeal neoplasms via styloid diaphragm approach / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To evaluate the surgical technique and efficacy of the resection of parapharyngeal space neoplasm via styloid diaphragm approach.</p><p><b>METHODS</b>Thirty-three cases underwent the resection of parapharyngeal space tumors via styloid diaphragm approach from Jan 2005 to Jan 2011 were reviewed. Of the cases, 28 were with benign tumors treated by surgery alone, and 5 were malignant tumors treated by surgery plus postoperative radical radiotherapy.</p><p><b>RESULTS</b>The parapharyngeal neoplasms in all cases were completely resected via styloid diaphragm approach. The postoperative follow-up ranged from 13 months to 7 years (median = 4.6 years). No tumor recurrence was found in 30 cases, but 3 cases experienced tumor recurrence, including 1 chondrosarcoma (3 years after surgery and chemoradiotherapy), 1 chordoma and 1 adenoid cystic carcinoma (5 years after surgery and radiotherapy). Severe postoperative complications were not observed, but 2 cases showed mild mouth askew and fully recovered after 3 months, and 1 case was complicated with hoarseness and cough symptoms that disappeared after heteropathy.</p><p><b>CONCLUSION</b>Resection of parapharyngeal neoplasms via styloid diaphragm approach is an ideal surgical technique, with well-exposed surgical field, less tissue injury, and less postoperative complication.</p>

EphA2 promotes angiogenesis and metastasis of head and neck squamous cell carcinoma in vivo / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To investigate the effects of EphA2 on the angiogenesis and cervical lymph node metastasis of squamous cell carcinoma of the head and neck (SCCHN) in vivo.</p><p><b>METHODS</b>EphA2 short hairpin (shRNA) lentiviral particles were used to knockdown the expression of EphA2 in SCCHN cell line M2 with high lymph nodes metastasis rate. Stable clones, obtained by puromycin screening, were assayed by RT-PCR and Western blot to validate the gene silencing efficiency and were used to establish SCCHN metastatic xenograft mouse model. Hematoxylin-eosin staining was applied to identify cervical lymph node metastasis of SCCHN in xenografted tumors. Immunohistochemistry was used to observe microvessel density. Western blot was used to investigate the protein expressions of EphA2 and vascular endothelial, growth factor (VEGF).</p><p><b>RESULTS</b>EphA2 shRNA lentiviral particles efficiently decreased the mRNA and protein expressions of EphA2 in SCCHN cell line M2, which were further successfully utilized to establish SCCHN metastatic xenograft mouse model. Compared with xenografted tumors in control group, xenografted tumors in M2EphA2RNAi(+) group decreased significantly tumor volume [(430.7 ± 190.0) mm(3) (x(-) ± s) vs (1179.0 ± 289.4) mm(3)] and weight [(0.26 ± 0.10) g vs (0.54 ± 0.12) g] (both P < 0.05). More importantly, bilateral cervical lymph node metastasis rate in M2EphA2RNAi(+) was also greatly declined (Mann-Whitney U = 10.0, P < 0.05). Decreased protein expressions of EphA2 and VEGF and microvessel density were observed in M2EphA2RNAi(+) group (t = 26.751, P < 0.01).</p><p><b>CONCLUSIONS</b>Knockdown of EphA2 expression led to the inhibition of tumor growth and metastasis in SCCHN nude mouse model. More importantly, SCCHN angiogenesis was also impeded, which might be associated with the decreased expression of VEGF.</p>

Expression of HMGB1 protein in laryngeal squamous cell carcinoma and its clinical significance / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the expression of HMGB1 protein in tissue specimens of laryngeal squamous cell carcinoma (LSCC) and adjacent normal mucosa, and explore the correlation of HMGB1 protein expression with clinicopathologic features and prognosis in LSCC.</p><p><b>METHODS</b>Ninty-three cases of LSCC and 5 cases of adjcent mucosal tissue samples were included in this study. Immunohistochemical staining was performed on paraffin-embedded tissue specimens to examine the HMGB1 protein expression. The data were futher correlated with the clinicopathological features and prognosis of the LSCC patients.</p><p><b>RESULTS</b>The positive rates of HMGB1 expression in LSCC specimens was 87.1%, significantly higher than that in the adjcent normal mucosa samples (46.7%, P = 0.001), and its overexpresion was closely correlated with T stage (Chi2 = 10.878, P = 0.004), clinical stage (Chi2 = 21.115, P < 0.01), metastasis (Chi2 = 28.298, P < 0.01) and recurrence (Chi2 = 14. 923, P = 0.001) in patients with LSCC. Patients with HMGB1 overexpression had both poorer disease-free survival and poorer overall survival compared with that in patients with low HMGB1 expression (Chi2 = 13.815, Chi2 = 11.912; Both P < 0.01). Univariate and multivariate Cox regression analyses revealed that HMGBI expression is an independent prognostic factor for patients with LSCC.</p><p><b>CONCLUSIONS</b>The results of this study demonstrate that HMGB1 protein expression is significantly increased in LSCC tissues, and HMGB1 protein overexpression is associated with a poorer prognosis in patients with LSCC. These results suggest that HMGB1 may play a critical role in the initiation and progression of LSCC, implicating HMGB1 may become a valuable marker for the prediction of prognosis in patients with LSCC.</p>

Endoscopic posterior septectomy for patients with nasopharyngeal tumor / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To explore the techniques, advantages and disadvantages, indications and cautions of a surgical approach for the resection of nasopharyngeal tumor.</p><p><b>METHODS</b>Ten cases with nasopharyngeal tumors were recruited in this study, of them, 3 cases with residual nasopharyngeal carcinoma after chemoradiotherapy, 2 cases with cavernous angioma, 2 cases with benign mixed tumor, 1 malignant mixed tumor, 1 adenoid cystic carcinoma, and 1 chordoma. All patients underwent endoscopic resection of posteroinferior quarter part of nasal septum, and then the removal of nasopharyngeal tumors through bilateral transnasal approach.</p><p><b>RESULTS</b>Total resection of the tumor was achieved for all cases without severe surgical complications. All cases with benign tumors, with following-up of 6-18 months, showed no recurrence. Of 6 cases with malignant tumors, with following-up of 12-48 months, 5 cases showed no recurrence, and 1 case was suspected to relapse one year postoperatively, but not with any lesion enlargement after another 6 month follow-up.</p><p><b>CONCLUSIONS</b>Posteroinferior quarter part of nasal septectomy is preferred for endoscopic resection of nasopharyngeal tumors because it can provide a panoramic view on nasopharyngeal cavity and tumors, thus, facilitating the removal of nasopharyngeal tumors.</p>

Correlation of EphA2 protein expression with clinicopathological characteristics and prognosis in laryngeal squamous cell carcinoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To evaluate the expression of EphA2 protein in tissue specimens and cell lines of laryngeal squamous cell carcinoma (LSCC), and to further study the correlation of EphA2 protein expression with clinicopathological characteristics and prognosis in LSCC.</p><p><b>METHODS</b>Western blot was applied to assess the EphA2 protein expression in LSCC cell line Hep-2 cells and the head and neck immortalized epithelial cell line NP-69 cells. Immunohistochemical staining was performed on paraffin sections of 88 cases of LSCC specimens and 16 cases of adjcent normal tissue samples to investigate the EphA2 protein expression, and to futher elucidate its correlation with clinicopathological characteristics.</p><p><b>RESULTS</b>Compared with the NP-69 cells, EphA2 expression in LSCC cell line Hep-2 cells was upregulated. The positive rates of EphA2 expression in LSCC and adjcent normal tissues samples were 80.7% and 43.8%, respectively, with a significant difference between the two groups (P < 0.001). EphA2 overexpresion was closely correlated with clinical stage (I + II/III + IV, P = 0.005), metastasis (P = 0.025) and recurrence (P = 0.021) in LSCC. Furthermore, patients with EphA2 overexpression had poorer tumor-free survival and 5-year overall survival compared with that in patients with low EphA2 expression (33.3% vs. 63.2%, P = 0.003; 46.7% vs. 81.6%, P = 0.002). EphA2 expression combined with clinical stage provided a better predictive value in prognosis. Univariate and multivariate Cox regression analysis revealed that EphA2 expression is an independent prognostic factor for patients with LSCC (P = 0.019).</p><p><b>CONCLUSIONS</b>The results of this study demonstrate that EphA2 protein expression is significantly increased in LSCC tissues and cell lines, and EphA2 protein overexpression is associated with tumor recurrence, metastasis and poorer prognosis in LSCC patients. These results suggest that EphA2 may play a critical role in the initiation and progression of LSCC, implicating EphA2 as a valuable marker for the prediction of recurrence, metastasis and prognosis in LSCC.</p>

Clinical study on mometasone furoate nasal spray in the treatment of non-allergic rhinitis / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To evaluate the outcome of mometasone furoate nasal spray (MFNS) used for 3 months on non-allergic rhinitis (NAR).</p><p><b>METHODS</b>In this multicenter study, NAR patients were enrolled from eight hospitals and received MFNS 200 microgram once daily for 3 months. The patients were followed-up for three times (at baseline, month 1 and month 3) to record the symptom scores and nasal endoscopic appearances. At the same time, the adverse events frequency was recorded and analyzed.</p><p><b>RESULTS</b>A total of 188 NAR cases were enrolled in the study. The total nasal symptom score assessment descended significantly at month 1 (1.70 ± 0.75) and month 3 (0.95 ± 0.79) visits versus at baseline (2.67 ± 0.68, Z value were from -11.603 to -10.491, all P < 0.01). The individual symptoms, including nasal stuffiness, nasal discharge, nasal stuffiness-related dizziness or headache, hyposmia, sleep quality, daily life activity, work or study efficiency, mental status, and whole body fatigue, also showed less scores at month 1 and month 3 visits versus at baseline (Z value were from -11.313 to -6.802, all P < 0.01). At the same time, nasal mucosal appearances assessed by endoscopy had lower scores at month 1 (1.40 ± 0.62) and month 3 (0.75 ± 0.71) visits versus at baseline (2.27 ± 0.73, Z value were from -11.484 to -10.002, all P < 0.01). Additionally, adverse events were only observed in 5.3% cases with light rhinorrhagia and nasal dryness. No other side effect was found.</p><p><b>CONCLUSIONS</b>A 3-months administration of intranasal mometasone can effectively and safely improve NAR patients' clinical symptom and nasal mucosal appearances.</p>

Tumor-targeted human telomerase reverse transcriptase promoter/tk gene therapy against human nasopharyngeal carcinoma cells in vitro / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the targeted killing effect of human telomerase reverse transcriptase promoter (hTERTp)/tk gene on human nasopharyngeal carcinoma (NPC) cells.</p><p><b>METHODS</b>The recombinant plasmid hTERTp/tk/pGL3 was transfected into human NPC HNE1 cells and the expressions of TK and telomerase were investigated. The targeted killing effect induced by hTERTp/tk on HNE1 cells was assessed using RT-PCR and MTT assay.</p><p><b>RESULTS</b>TK gene expression was detected in HNE1 cells transfected by hTERTp/tk/pGL3, and the cells showed reduced telomerase and hTERT expression as compared with the control cells. hTERTp/tk/pGL3 resulted in target killing of HNE1 cells but not of the normal control cells. The tumor cell-killing effect of hTERTp/tk/pGL3 was slightly milder than that of the positive control CMV/tk/pGL3 that produced nonselective cell killing.</p><p><b>CONCLUSION</b>hTERTp/tk, a tumor-specific expression system, allows targeted tumor cell killing and reduces the activity of telomerase in NPC cells in vitro.</p>

Prevention and management of complications of endoscopic surgery for nasal-skull base neoplasms / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To analyze the surgical complications of endoscopic nasal-skull base surgery. The secondary objective was to propose the preliminary strategies for prevention and treatment of complications.</p><p><b>METHODS</b>One hundred and thirty two patients with nasal-skull base tumors undergoing endoscopic or endoscope-assisted surgery were included in this study. Surgical approaches included endoscopic endonasal transethmoidal approaches, endoscopic endonasal transseptal transsphenoidal approach, extended endoscopic endonasal transseptal transsphenoidal approach, endoscopic transmaxillary posttrial wall approach, extended endoscopic transmaxillary posttrial wall approach, endoscopic nasal lateral wall dissection, maxillary osteotomy approach and endoscopic transoropharyngeal approach. These approaches were selectively used to resect the tumors in the area of nasal-skull base.</p><p><b>RESULTS</b>The total resection of the tumors was obtained in 104 patients (104/132, 78.8%), with 29.5% (39/132) incidence of complications, including profuse bleeding, nerve injury, cerebrospinal fluid leakage, diabetes insipidus, electrolyte imbalance, hyperglycemia, and psychological disturbance. No catastrophic complications, sequelae and operative mortality encountered. Four months to 8 years' follow up (median 3.0 years) indicated that recurrence rate of the benign tumor was 9% (9/100) without died case, and 3-year and 5-year survival rates of the malignant tumor were 75.0% and 55.6%, respectively.</p><p><b>CONCLUSIONS</b>Strategies proved to be effective in reduction of the overall incidence of the complications, especially in minimizing the catastrophic complications and sequelae. The strategies were as follows: first, according to original site, extension and characteristics of the tumor, designing appropriate endoscopic approaches for the treatment of skull base tumor; second, recognizing reliable surgical access points and safe plane of the dissection; third, predicting surgical risks preoperatively and proposing the corresponding plan to avoid these risks; fourth, acquainted with the endoscopic skills and familiarized the skull base structures; lastly, ensuring the correct management of the interdisciplinary problems with close collaboration with the interdisciplinary medical personnels.</p>

Global gene expression profiling of laryngeal squamous cell carcinoma by laser capture microdissection and complementary DNA microarrays / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To examine the gene expression profile of laryngeal squamous cell carcinoma (LSCC) by combination of laser capture microdissection (LCM) and microarray and to identify genetic changes in disease pathogenesis.</p><p><b>METHODS</b>The study analysed 8 matched pairs of specimens of glottic carcinoma of larynx and histologically normal epithelium tissues adjacent to the carcinoma preserved in the RNA later reagent. A genome-wide transcriptome analysis was performed by probing 16 cDNA microarrays with fluorescent-labeled amplified RNA derived from laser capture microdissected cells. Real-time quantitative (RT-PCR) of tissue microarray was used to validate the reliability of cDNA microarrays.</p><p><b>RESULTS</b>Significant analysis of microarray (SAM) software and hierarchical cluster analysis of the expressed genes showed that 2351 genes was significantly expressed respectively according to different analysis method (false discover rate = 0.63%). A selected set of MMP12, KRT16, RARB, PRB1 genes was identified to be consistent with array data by RT-PCR.</p><p><b>CONCLUSIONS</b>The analysis of gene ontology and pathway distributions futher highlighted genes that may be critically important to laryngeal carcinogenesis. The results strongly suggest that this new approach may facilitate the identification of clinical molecular markers of disease and novel potential therapeutic targets for LSCC.</p>

Surgical approaches for different stages of nasopharyngeal angiofibromas / 中华耳鼻咽喉头颈外科杂志

<p><b>OBJECTIVE</b>To explore the optical surgical approaches for the resection of early and advanced stage of nasopharyngeal angiofibromas.</p><p><b>METHODS</b>Twenty two male patients aged 9 - 30 years (median 16 years) hospitalized in Xiangya Hospital from June 2003 to July 2006 with nasopharyngeal angiofibroma were recruited. Five operative approaches were selected according classification of juvenile nasopharyngeal angiofibroma described by Fisch. Six cases with stage I nasopharyngeal angiofibroma underwent endoscopic transnasal surgery. Six cases with stage II and 2 cases with stage III underwent endoscopic endonasal middle meatal transmaxillary-antrum approach. Three cases with stage III and 2 cases with stage IV underwent endoscopic endonasal middle and inferior meatal approach with extended transmaxillary-antrum resection. One case with stage IV underwent microscopic preauricula infratemporal fossa approaches combined with endoscopic endonasal middle and inferior meatal transantral approach. Two cases with stage IV underwent nasomaxillary osteotomy approach.</p><p><b>RESULTS</b>After surgery, CT scan or MR image showed that total removal of the tumor was achieved in 21 patients. One patient who received subtotal resection were performed by second endoscopic surgery and obtained total resection. No postoperative complications have been encountered in all treated patients. Nine months to 3 years follow up indicated that no cases recurred after surgery.</p><p><b>CONCLUSIONS</b>Appropriate surgical approach should be selected according to the clinical classification and whether the tumor has extended into whole nasal cavity, lateral fossa infratemporalis, intracranial or not. Such approaches might better facilitate the complete removal of nasopharyngeal angiofibromas and reduce the surgery-related injury.</p>

Clinical analysis of pneumomediastinum or pneumothorax during the removal of brochial foreign bodies / 中南大学学报(医学版)

OBJECTIVE@#To discuss the etiology, diagnosis, treatment, and prevention of pneumomediastinum or pneumothorax during the removal of bronchial foreign bodies in children.@*METHODS@#We analyzed the clinical data of 10 cases of pneumomediastinum or pneumothorax during the removal of bronchial foreign bodies in children.@*RESULTS@#Two patients died and the other 8 were cured.@*CONCLUSION@#Pneumomediastinum or pneumothorax is mainly caused by the intrapulmonary hyper-pressure and fracture of pulmonary bubbles. The prognosis of pneumomediastinum or pneumothorax is closely related to such factors as correct and punctual diagnosis and quick removal of the airway obstruction.

Combining FCU/5-FU suicide gene/prodrug system and radiation in treating nasopharyngeal carcinoma: an experimental study / 中华病理学杂志

<p><b>OBJECTIVE</b>To explore the in vitro, in situ and in vivo killing effects to CNE-2 cells of human nasopharyngeal carcinoma (NPC) by FCU/5-FC system combined with gamma irradiation for predicting the treatment effect on NPC.</p><p><b>METHODS</b>Plasmid pcDNA3.1(-)CMVe.Egr-1. FCU was introduced into CNE-2 cells by electroporation. The transfected cells were selected by G418 (600 microg/ml) for 14 days to yield cells expressing FCU stably. The FCU protein in transfected CNE-2 cells was tested by Western blotting. In vitro response of FCU-expressing CNE-2 cells to 5-FC or gamma irradiation, alone or in combination was detected by MTT assay. Furthermore, A NPC model was employed by inoculating CNE-2 cells in the right flank of nude mice for in situ gene therapy, and after 12 days of inoculation, those rats were randomized to seven groups, then the suppression of NPC growth in model was observed after giving different treatments. Finally, FCU-expressing CNE-2 cells were inoculating in the right flank of nude mice to generate NPC xenografts for in vivo gene therapy, and after 5-day of implantation, those rats were randomized to seven groups, then the delaying of tumour growth was observed in xenografts treated with different conditions.</p><p><b>RESULTS</b>A anticipated relative molecular quality 42,000 protein was obtained from total protein of FCU-expressing CNE-2 cells. The growth of FCU-positive CNE-2 cells were inhibited by 5-FC or gamma irradiation, alone or in combination, but cells treated with both 5-FC and gamma irradiation resulted in enhanced cell killing when compared with cells treated with gamma irradiation or 5-FC alone. In vitro study showed that the relative survival rates of FCU-expressing CNE-2 cells treated with gamma irradiation were 15.85% - 97.88%, while that of gamma irradiation + 5-FC (100 microg/ml) group were 6.58% - 50.00%, and there was a significant difference (P < 0.01). The MTT results also demonstrated that the relative survival rate has a striking different (P < 0.01) between 5-FC group (12.11% - 99.51%) and 5-FC + gamma irradiation (1.0 Gy) group (2.37% - 35.87%). Not only in situ but also in vivo, potent growth inhibition on the explanted NPC tumours was observed in mice treated with 5-FC or gamma irradiation, alone or in combination, among which interference of both 5-FC and gamma irradiation leaded to most distinct suppression of tumour growth. Tumour volumes in groups interfered by 5-FC and or gamma irradiation were extinctly different with the control group and PBS treatment group (P < 0.05).</p><p><b>CONCLUSION</b>CNE-2 cells or nasopharyngeal carcinoma venograph could be killed by FCU/5-FC suicide gene prodrug system or gamma irradiation, and there is a synergistic therapeutic effect on NPC between FCU/5-FC and gamma irradiation.</p>

Clinical analysis of 170 cases head and neck lymphoma / 中南大学学报(医学版)

OBJECTIVE@#To study the characteristics of head and neck lymphoma in order to improve its diagnose rate.@*METHODS@#Review and analysis 170 patients with head and neck lymphoma in department of otolaryngology of Xiangya hospital from 1997 to 2005.@*RESULTS@#Nasal cavity and nasal sinuses, neck, tonsil were the common place of the origin of head and neck lymphoma. There are 9 cases Hodgkin disease and 161 cases non-Hodgkin lymphoma (NHL). T cellularity, B cellularity lymphoma, the mixed pattern and nullityping accounted for 60.9%, 36.0% and 3.1% of these patients with NHL, respectively. CHOP and radiotherapy were the main treatment method.@*CONCLUSION@#The clinical and imageology manifestation of head and neck lymphoma were of diversification and no specificity, whose final diagnosis depended on immunohistochemistry.

Primary functional analysis of CK13 gene 5' flanking region / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the mechanism of cytokeratin 13 (CK13) gene expression control and the effects of different motifs of CK13 gene 5' flanking region on its transcriptional activity.</p><p><b>METHODS</b>The molecular clone technique and reporter gene analysis were used to assay the effects of different motifs of 513 bp of CK13 gene 5' flanking region on its transcriptional activity. The pCAT enhancer vectors with different motifs of CK13 gene 5' flanking region were constructed and transferred to HeLa cells with the help of lipofectin. The instant CAT expression of different clones was detected and the effects of different motifs of the CK13 gene 5' flanking region on its transcriptional activity were evaluated.</p><p><b>RESULTS</b>119 bp from -nt.325 to -nt.207 upstream of the first ATG of CK13 gene 5' flanking region included a silent element. 113 bp region from -nt.206 to -nt.94 included an enhanced element.</p><p><b>CONCLUSION</b>513 bp of CK13 gene 5' flanking region includes a silent element and an enhanced element. Further locating these cis elements and detecting the related trans reaction factors may unveil some important clues to the details of the mechanisms for the CK13 gene expression and tissue-specific expression.</p>