Kong Weijia

Promoter hypermethylation of DNA repair gene MGMT in laryngeal squamous cell carcinoma

The relationship between hypermethylation of CpG islands in the promoter regions of O6-methylguanine DNA methyltransferase (MGMT) genes and laryngeal squamous cell carcinoma was explored. Methylation-specific PCR and semi-quantitative RT-PCR were used to study the promoter methylation and mRNA expression of the MGMT gene in laryngeal carcinoma tissues, tissues adjacent to the tumor and normal laryngeal tissues. Hypermethylation of MGMT gene was detected in 16 samples of 46 (34.8%) laryngeal squamous cell carcinoma samples. However, the MGMT hypermethylation was not detected in all tissues adjacent to the tumors and normal tissues. No significant difference in MGMT gene hypermethylation was found in samples with different histological grades (chi2 = 3.130, P = 0.077) or in samples from patients with different TNM status (chi2 = 3.957, P = 0.138). No expression of MGMT mRNA was detected in all hypermethylated laryngeal carcinoma tissues. The expression of MGMT mRNA was detected in all unmethylated laryngeal carcinoma tissues, tissues adjacent to the tumors and normal tissues. It suggests that MGMT gene promoter hypermethylation is associated with MGMT gene transcription loss in laryngeal carcinoma tissues and possibly plays an important role in carcinogenesis of laryngeal tissues.SummaryThe relationship between hypermethylation of CpG islands in the promoter regions of O6-methylguanine DNA methyltransferase (MGMT) genes and laryngeal squamous cell carcinoma was explored. Methylation-specific PCR and semi-quantitative RT-PCR were used to study the promoter methylation and mRNA expression of the MGMT gene in laryngeal carcinoma tissues, tissues adjacent to the tumor and normal laryngeal tissues. Hypermethylation of MGMT gene was detected in 16 samples of 46 (34.8%) laryngeal squamous cell carcinoma samples. However, the MGMT hypermethylation was not detected in all tissues adjacent to the tumors and normal tissues. No significant difference in MGMT gene hypermethylation was found in samples with different histological grades (χ3=3.130,P=0.077) or in samples from patients with different TNM status (χ2=3.957,P=0.138). No expression of MGMT mRNA was detected in all hypermethylated laryngeal carcinoma tissues. The expression of MGMT mRNA was detected in all unmethylated laryngeal carcinoma tissues, tissues adjacent to the tumors and normal tissues. It suggests that MGMT gene promoter hypermethylation is associated with MGMT gene transcription loss in laryngeal carcinoma tissues and possibly plays an important role in carcinogenesis of laryngeal tissues.

A possible association of staphylococcus enterotoxin B-induced asthma and sinusitis

SummaryIn order to gain insight into a possible association between chronic sinusitis and asthma, 85 patients with sinusitis and asthma underwent functional endoscopic sinus surgical treatment and serum antibodies and cytokines were measured. The results showed that 51 out of 85 patients with high serum anti-Staphylococcus enterotoxin B (SEB) antibody before treatment obtained satisfactory results for both sinusitis and asthma. The high level of Th2 cytokine IL-4 was down regulated to the levels of normal controls after sinus surgery. Thirty-four out of 85 patients did not show high serum anti-SEB antibody before sinus surgery and did not show much improvement, in their asthmatic symptoms although sinusitis symptoms were resolved by sinus surgery. It was concluded that bacterial superantigen SEB (in the sinuses) might play a crucial role in the pathogenesis of lower airway hypersensitivity.

Vascular endothelial growth factor165-regulated nasopharyngeal carcinoma cell lines invasion and migration involve expression and activation of matrix metalloproteinase-2

The effect of vascular endothelial growth factor (VEGF) overexpression on matrix metalloproteinase-2 (MMP-2) in nasopharyngeal carcinoma (NPC) cells in vitro and the possible mechanism involved were investigated, and the correlation between the expression of VEGF and MMP-2 in NPC evaluated. The NPC cells were transfected with PAd-trackVEGF165 plasmid. The expression levels of VEGF and MMP-2 mRNA and protein in NPC cells were detected by semi-quantitative RT-PCR and Western blot respectively. It was found that the expression of VEGF and MMP-2 mRNA and protein was significantly increased in NPC cells after transfection of VEGF165. It was concluded that the expression of VEGF was correlated to the in vitro invasion of NPC cells, and the induction of MMP-2 by VEGF was a key process of NPC cell invasion.

Relationship between the expression of CD44v6 and development, progress, invasion and metastasis of laryngeal carcinoma

SummaryThe expression of CD44v6 and its relationship with the development, progress, invasion and metastasis of laryngeal carcinoma was investigated. The expression and content of CD44v6 mRNA in tissuess were detected by both RT-PCR and FCM which were respectively extracted from normal laryngeal mucosa, leukoplakia of larynx, laryngeal papilloma, polyp of vocal cord, tissues of laryngeal carcinoma, metastatic and nonmetastatic lymph nodes of neck, and tissues close to carcinoma. the outcome of RT-PCR indicated that the expression rate of CD44v6 mRNA involved in tissues of laryngeal carcinoma and metastatic lymph nodes of neck was the highest (90%–100%) compared with that of leukoplakia of larynx, laryngeal papilloma, tissues close to carcinoma by 0.5 cm (55.56%–60.00%) and that of normal laryngeal mucosa, polyp of vocal cord, nonmetastatic lymph nodes and tissues close to carcinoma by 1.0 cm was the lowest (13.33%–20%). The result from FCM was highly consistent with that from RT-PCR. It was suggested that CD44v6 was closely related with the development, progress, invasion and metastasis of laryngeal carcinoma. The outcome from the tissues close to carcinoma by different distance could do help to the determination of incisal edge in surgery abstractly.

A CORRELATIVE STUDY OF Ki67 AND VASCULAR ENDOTHELIAL GROWTH FACTOR AND THEIR VALUE IN LARYNGEAL SQUAMOUS CELL CARCINOMA

Objective: To study the correlation between Ki67 and vascular endothelial growth factor(VEGF) and the significance of their expression in laryngeal squamous cell carcinoma(LSCC). Methods: The expressions of Ki67 and VEGF in 40 cases of LSCC and 5 cases of normal laryngeal mucosa were examined by immunohistochemical staining. Results: The expression levels of Ki67 and VEGF in LSCC tissue were higher than in normal laryngeal mucosa (Ki67: P<0.001, VEGF: P<0.001). The two indexes’ levels in patients of different age or different sex had no significant difference (P>0.05). They were higher in LSCC with metastasis of lymph nodes than in patients without metastasis (Ki67: P=0.034, VEGF: P=0.006). The expressions of the two genes elevated correspondingly along with the development of LSCC T stage (P<0.05). In addition, correlation analysis indicated that the expression of Ki67 had a positive correlation with VEGF in LSCC(r=0.823, P<0.01). Conclusion: Ki67 and VEGF are objective indexes for the biological behavior of LSCC, and they might be helpful to the diagnosis, treatment and prognosis of laryngocarcinoma.

Relation between the Expression of K-ras in Hep-2 Cells and Development of Laryngeal Carcinoma

AbstractObjective: To investigate the expression of K-ras in human laryngeal squamous cell carcinoma cell lines (Hep-2) and its significance for establishing a solid foundation for further study of the relationship between human laryngeal squamous cell carcinoma and K-ras gene point mutations. Methods: The expression of K-ras in human laryngeal squamous cell carcinoma cell lines (Hep-2) and human pancreatic carcinoma cell lines (MIAPaCa-2) was detected by using RT-PCR. Results: The expression of K-ras mRNA in Hep-2 and MIAPaCa-2 was strong and positive. Conclusion: The expression of K-ras mRNA in human laryngeal squamous cell carcinoma cell lines (Hep-2) is positive. Development of laryngeal carcinoma might be related to the activation of K-ras gene point mutation.

Partial horizontal laryngectomy and epiglottiplasty

In order to evaluate the availability of the lateral horizontal laryngectomy and anaplasty of epiglottis to treat some patients with specific supraglottic carcinomas and hypopharyngeal carcinomas, 17 cases of laryngeal and hypopharyngeal carcinomas were retrospectively analyzed, whose tumors were located at the lateral margin of epiglottis, aryepiglottic fold, medial wall of piriform fossa and were treated by the lateral horizontal laryngectomy and anaplasty of epiglottis. The results showed that all cases took food by mouth in postoperative 9-14 days and subjected to decannulation in postoperative 9-15 days. Three cases had postoperative hoarse voice. The free-disease survival rate of 3 years was 71.4% in 14 cases followed up after the first surgical therapy, and the overall free-disease survival rate of 3 years was 85.7% after the second surgical therapy. It was concluded that the manipulations of the lateral horizontal laryngectomy and epiglottiplasty were simple. It could alleviate the postoperative symptoms of aspiration and bucking remarkably and shorten their postoperative recovery time, yet does not lower the survival rate of patients if laryngocarcinoma or hypopharyngeal carcinoma cases were properly selected.SummaryIn order to evaluate the availability of the lateral horizontal laryngectomy and anaplasty of epiglottis to treat some patients with specific supraglottic carcinomas and hypopharyngeal carcinomas, 17 cases of laryngeal and hypopharyngeal carcinomas were retrospectively analyzed, whose tumors were located at the lateral margin of epiglottis, aryepiglottic fold, medial wall of piriform fossa and were treated by the lateral horizontal laryngectomy and anaplasty of epiglottis. The results showed that all cases took food by mouth in postoperative 9–14 days and subjected to decannulation in postoperative 9–15 days. Three cases had postoperative hoarse voice. The free-disease survival rate of 3 years was 71.4% in 14 cases followed up after the first surgical therapy, and the overall free-disease survival rate of 3 years was 85.7% after the second surgical therapy. It was concluded that the manipulations of the lateral horizontal laryngectomy and epiglottiplasty were simple. It could alleviate the postoperative symptoms of aspiration and bucking remarkably and shorten their postoperative recovery time, yet does not lower the survival rate of patients if laryngocarcinoma or hypopharyngeal carcinoma cases were properly selected.

The effects of DPPH on cochlear microcirculation.

SummaryTo investigate the effects of the free radical, 1,2-Diphenyl-2-picylhydrazyl, on cochlear blood flow, 20 guinea pigs were divided into 3 groups at random, 6 for control group, 6 for 1 mmol/L group and 8 for 0.1 mmol/L group. 2 μl vehicle or drugs were dropped into round window membrane (RWM). Cochlear microcirculation was monitored by laser Doppler flowmeter (LDF), and mean arterial blood flow (MABP), which was transferred by pressure conductor sensor and preamplifier, was simultaneously recorded on the computer. Our results showed that MABP was stable throughout the experiment. Cochlear blood flow (CBF) increased by 10.32% (P <0.05) in 1 mmol/L group, and decreased by 4.89% in 0.1 mmol/L group (P<0.05). In control group cochlear microcirculation showed no significant changes. It is concluded that DPPH exerted effects on cochlear microcirculation.

Firing Properties and Classification of MVN Neurons in Rats

SummaryIn order to know the effects of caloric stimulation on neuronal firing in medial vestibular nuclei (MVN) by middle ear irrigation, the middle ear was irrigated with ice (4°C), hot (44°C), and warm (37°C) water, and the firing rate of MVN neuron was extracellularly recorded. The results showed that the firing rate of MVN neuron was changed by caloric stimulation, and the majority of MVN neurons showed excitation by irrigation with hot water and inhibition by ice water (type A). The neuronal firing was recovered immediately after the cessation of the stimulation. I It was concluded that the neuronal firing rate in MVN was changed by caloric stimulation in middle ear cavity. The response was different in various neurons.