Biomedical subjects

Yun-Fei Xia

Publications and source records attributed to Yun-Fei Xia.

At least 19 recordsLinked to original sources

PubMed2006

Quality of life of nasopharyngeal carcinoma survivors in Mainland China.

The aim of this study is to evaluate the quality of life (QoL) of nasopharyngeal carcinoma (NPC) survivors. 192 NPC survivors treated in 1999 and 2000 were enrolled in this study. Median follow up was 3.6 years (range 2.4-4.6 years). The Chinese SF-36 questionnaire and a self-reported symptom checklist consisting of 14 items were completed at clinics. Sociodemographic factors and clinical information were also collected. Most functional domains of the Chinese SF-36 were significantly worse in NPC survivors compared to the normal population. Xerostomia, hearing loss, hypomnesia, dysphagia, and trismus were frequently reported symptoms. Sociodemographic variables including gender, age, dialect, educational level, monthly income, economic status, and number of comorbidities were univariate predictors of different SF-36 domains and symptoms. Patients with earlier T and N stage, irradiated by linear accelerator, with lower dose and weekly dose to nasopharynx and neck, and those who had anterior nasal radiation field reported better QoL. Multiple stepwise regression analysis showed that the number of comorbidities, monthly income, age, and T stage were independent factors affecting global QoL. We concluded that NPC survivors had worse QoL than the normal population and improving radiotherapy might increase physical and functional domain of QoL.

Adolescent↗

PubMed2006

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. Importantly, Bmi-1 was also found to be overexpressed in 29 of 75 nasopharyngeal carcinoma tumors (38.7%) by immunohistochemical analysis. In contrast to nasopharyngeal carcinoma, there was no detectable expression of Bmi-1 in noncancerous nasopharyngeal epithelium. Moreover, high Bmi-1 expression positively correlated with poor prognosis of nasopharyngeal carcinoma patients. We also report that the overexpression of Bmi-1 leads to bypass of senescence and immortalization of NPECs, which normally express p16(INK4a) and exhibit finite replicative life span. Overexpression of Bmi-1 in NPECs led to the induction of human telomerase reverse transcriptase activity and reduction of p16(INK4a) expression. Mutational analysis of Bmi-1 showed that both RING finger and helix-turn-helix domains of it are required for immortalization of NPECs. Our findings suggest that Bmi-1 plays an important role in the development and progression of nasopharyngeal carcinoma, and that Bmi-1 is a valuable marker for assessing the prognosis of nasopharyngeal carcinoma patients. Furthermore, this study provides the first cellular proto-oncogene immortalized nasopharyngeal epithelial cell line, which may serve as a cell model system for studying the mechanisms involved in the tumorigenesis of nasopharyngeal carcinoma.

Biomarkers, Tumor↗

PubMed2006

The effect of p21 antisense oligodeoxynucleotides on the radiosensitivity of nasopharyngeal carcinoma cells with normal p53 function.

OBJECTIVE: p21(WAF1/CIP1) is transcriptionally activated by p53 and is required for G1 to S phase progression. p21 plays a critical role in DNA repair after DNA damage. Thus, cells with defective p21 may result in an enhancement of radiation induced apoptosis and improved radiosensitivity. We tested the hypothesis that p21 antisense oligodeoxynucleotides (p21 AS ODNs) can be used to reduce p21 expression level and increase radiosensitivity in CNE-1-wtp53 nasopharyngeal carcinoma cell line with normal p53 function. METHODS AND MATERIALS: The p21 antisense oligodeoxynucleotides (p21 AS ODNs) and the random control oligodeoxynucleotides (p21 RD ODNs) were synthesized. p21 AS ODNs sequence: 5'-TGTCATGCTGGTCTGCCGCC-3'; p21 RD ODNs sequence: 5'-CCGGTGAACGAGCGAGCACA-3'. p21 AS ODNs and p21 RD ODNs were transfected into CNE-1-wtp53 nasopharyngeal carcinoma cell line. The protein expression levels of P21 were evaluated using Western blotting analysis. Cell cycle progression and apoptotic cells were assessed by flow cytometric analysis. The clonogenic survival assay was performed to determine the survival fraction. The parameters D0, Dq, and N for the single-hit multitarget model and the parameters alpha, beta, alpha/beta, and SF2 for the linear-quadratic model were calculated. BALB/c nude mice were used to investigate the effect of p21 AS ODNs on the radiosensitivity of nasopharyngeal xenografts in vivo. RESULTS: p21 AS ODNs were detected mainly in plasma with fluorescence microscopy investigation. P21 protein level dramatically decreased and the amount of apoptotic cells increased in p21 AS ODNs transfected cells than in p21 RD ODNs transfected cells after irradiation. The percentage of G1 arrest decreased in p21 AS ODNs transfected cells 24 h after radiation, then G2 arrest decreased 48 h after radiation. The values of D0, Dq, SF2 decreased and alpha value increased in p21 AS ODNs transfected cells than in control cells. The inhibition rate in tumor xenografts exposed to X ray of 10 Gy alone was 39.1%, while it was 51.4% in xenografts injected with p21 AS ODNs before exposure to radiation. Unfortunately, there was no significant difference between these two groups (P < 0.05). CONCLUSION: p21 Antisense oligodeoxynucleotides led to inhibition of P21 protein expression, loss of G1 arrest, increase of apoptosis in CNE-1-wtp53 nasopharyngeal carcinoma cell line in vitro and inhibited tumor growth in vivo. Antisense oligodeoxynucleotides may become a promising strategy to enhance radiosensitivity in nasopharyngeal carcinoma cells with normal p53 function.

Animals↗

PubMed2006

[Radioresistant subline of human glioma cell line MGR2R induced by repeated high dose X-ray irradiation].

BACKGROUND & OBJECTIVE: Radiotherapy is one of the most important adjuvant treatments for patients with malignant glioma, but radiosensitivities of gliomas are widely various. This study was to induce human glioma cell line MGR2 to become a stable radioresistant cell subline, and investigate the mechanisms of radioresistance. METHODS: Human glioma cell line MGR2, with survival fraction of 2 Gy (SF(2)) of 0.18+/-0.05, was irradiated by intermittent high dose X-ray (2 Gy for 3 times, 5 Gy for 2 times). After each irradiation, the cells were cultured for 5 to 8 weeks and received irradiation again. The whole process of irradiation and culture lasted for 11 months. The cells derived from MGR2 were obtained and named MGR2R (MGR2 radiation induction). Double times of MGR2 and MGR2R cells were determined by MTT assay. Dose-survival curves, radiobiological parameters and SF2 were determined by colony-forming assay and line-quadratic model. The variation of their cell cycles was investigated by flow cytometry and cell cycle synchronization of serum-starvation. RESULTS: The double time of MGR2 cells was 3.6 days, while that of MGR2R cells was 4.0 days. The growth rate of MGR2R cells was slower than that of MGR2 cells. Using colony-forming assay and line-quadratic model, the parameters of MGR2 and MGR2R were obtained. The alpha values of MGR2 and MGR2R were 0.447 and 0.089 (t=4.524, P=0.011), the beta values were 0.177 and 0.141 (t=1.562, P=0.193), and the SF(2) were 0.208 and 0.478 (t=-6.062, P=0.040), respectively. The radioresistance of MGR2R cells was stronger than that of MGR2 cells. The distribution of cell cycle in MGR2 cells after synchronization were 54.8% in G(1) phase, 30.9% in S phase, and 14.3% in G(2) phase; 24 h after loss of synchronization, the distribution of cell cycle were 35.9% in G(1) phase, 51.2% in S phase, and 12.8% in G(2) phase. The distribution of cell cycle in MGR2R cells after synchronization were 55.7% in G(1) phase, 27.8% in S phase, and 16.6% in G(2) phase; 24 h after loss of synchronization, the distribution of cell cycle were 56.4% in G1 phase, 26.7% in S phase, and 16.9% in G(2) phase. MGR2R cells appeared G(2) phase arrest before synchronization, and G1 phase arrest after loss of synchronization. CONCLUSIONS: After intermittent high dose X-ray irradiation, radiosensitive cell line MGR2 has been induced to be relatively radioresistant (MGR2R). MGR2R cells grow slower and have G(1) phase and G(2) phase arrest which might relate to its radioresistance.

Brain Neoplasms↗

PubMed2006

[Staging 915 cases of nasopharyngeal carcinoma after simple radical radiotherapy (Part II)--Checkout of AJCC/UICC staging system (1997)].

BACKGROUND & OBJECTIVE: On the basis of our previous research, this study was to validate the rationality of AJCC/UICC staging system (1997) of nasopharyngeal carcinoma (NPC), and to provide some suggestions. METHODS: Survival data of 915 NPC patients, received radical radiotherapy alone in Cancer Center of Sun Yat-sen University from Jan. 1997 to Dec. 1998, were analyzed with Life table, Cox regression, Kaplan-Meier, and log-rank methods. RESULTS: Cox regression analysis showed that the 5-year survival rate of the 915 patients was significantly correlated to their age and tumor stage classified according to AJCC/UICC (1997) staging system; while that of the 803 patients no more than 60 years old was only significantly correlated to tumor stage. Life table analysis validated that the tumor stage classified according to AJCC/UICC staging system can roughly predict the prognosis, but the differences between stage I and IIa, or IVa and IVb were not significant. Kaplan-Meier analysis showed no significant differences of survival rate between stage T1 and T2a, or T3 and T4 when adjusted by N classification, and between stage N2 and N3a, or N3a and N3b when adjusted by T classification. Therefore, we adjusted stage T2a to T1, stage N1 with inferior cervical nodes metastasis to N2, combined stage N3a and N3b to N3, adjusted stage IIa to I, stage IIb to II, and stage IVb to IVa. After the modifications, the differences among stages I-IVa, T1-T4 (adjusted by N classification) and N0-N3 (adjusted by T classification) were significant. CONCLUSION: Taking the impact of age on the prognosis and the interaction between T stage and N stage into consideration, the above modifications should be included when renewing the AJCC/UICC staging system (1997).

Age Factors↗

PubMed2006

[Primary central nervous system lymphoma--a report of 32 cases with literature review].

BACKGROUND & OBJECTIVE: The incidence of primary central nervous system lymphoma (PCNSL) is increasing, and its prognosis is poor. This study was to investigate the clinical features of PCNSL, and evaluate the efficacy of high-dose methotrexate (MTX)-based chemotherapy for immunocompetent Chinese patients with PCNSL. METHODS: Clinical data of 32 patients (median age, 50 years) with pathologically confirmed PCNSL were analyzed retrospectively. Before Nov. 2001, CHOP with or without whole brain radiotherapy (WBRT) was employed; after then, high-dose MTX-based chemotherapy with or without WBRT was employed. RESULTS: Of the 32 PCNSL patients, 25 (78.1%) were more than 45 years old; 24 (75.0%) suffered intracranial hypertension; 25 (78.1%) had single intracranial mass; no positive case of cerebrospinal fluid (CSF) cellular examination was found; 28 (87.5%) were B-cell lymphoma, among which 19 (59.4%) were diffuse large B-cell lymphoma. Median follow-up of the patients was 13.5 months (1-84 months). Kaplan-Meier test showed that the median overall survival time was 26 months, and the 2-year survival rate was 45.7%. The complete response rate of the 18 patients who received high-dose MTX-based chemotherapy plus WBRT was 61.1%, the median survival time was more than 26 months, and the 2-year survival rate was 65.1%. The efficacy of high-dose MTX-based chemotherapy plus WBRT was better than that of CHOP plus WBRT. Log-rank test showed that the survival time of the patients with performance status (PS) of 0-1 or normal serum lactate dehydrogenase (LDH) was longer than those with PS of 2-3 or elevated LDH. CONCLUSIONS: PCNSL often occurs in middle-aged and aged patients, with intracranial hypertension as the main clinical manifestation. B-cell lymphoma is the predominant subtype. High-dose MTX-based chemotherapy plus WBRT is efficient and feasible for PCNSL.

Adolescent↗

PubMed2006

[Radiosensitization of nasopharyngeal carcinoma cell line CNE1 by inhibiting the expression of ATM/PI3K functional region].

BACKGROUND & OBJECTIVE: It is reported that ATM gene is closely correlated to cellular radiosensitivity in several malignant tumors. Suppression of ATM protein expression leads to cellular radiosensitization. This study was to determine whether this effect also exists in nasopharyngeal carcinoma (NPC) cell line CNE1 by inhibiting the expression of ATM protein through antisense RNA of ATM/PI3K region, which is the most important functional fragment of ATM gene. METHODS: The recombinant pDOR-atm expressing antisense RNA of ATM/PI3K segment was constructed with retroviral vector pDOR. CNE1 cells were stably transfected with pDOR-atm by cationic liposome and named CNE1/pDOR-atm. Semi-quantitive RT-PCR was used to detect the level of ATM mRNA. Flow cytometry (FCM) was employed to analyze the percentage of positive cells and mean fluorescence density of protein expressing ATM. Cellular radiosensitivity was evaluated by colony survival assay (CSA) and linear-quadratic model in both CNE1/ pDOR-atm and control cells. RESULTS: The level of ATM mRNA index (RI) was 0.23+/-0.02 in CNE1/pDOR-atm group, and 0.51+/-0.03 in control group (P<0.05). The percentage of positive cells and mean fluorescence density of proteins expressing ATM were 70.8% and 1.81+/-0.12 in CNE1/pDOR-atm group, while 99.3% and 4.51+/-0.18 in control group(P<0.01). The expression of ATM mRNA and protein was inhibited by antisense RNA. The alpha value (one function from linear-quadratic model) of CNE1/pDOR-atm group was 0.40 Gy(-1), while it was 0.36 Gy(-1) in control group. The radiosensitizing ratio of surviving fraction at 2 Gy (SF(2)) was 3.0, indicating that antisense RNA group was more radiosensitive to X-ray than the controls. CONCLUSION: NPC cell line CNE1 could be radiosensitized by the down-regulation of ATM/PI3K expression.

Ataxia Telangiectasia Mutated Proteins↗

PubMed2006

[Primary non-Hodgkin's lymphoma of the nasal cavity at early stage: long-term treatment outcomes and prognostic analyses of 108 cases].

BACKGROUND & OBJECTIVE: Primary non-Hodgkin's lymphoma (NHL) of the nasal cavity has unique clinicopathologic features, and optimal treatment regimen remains unclear. This study was to summarize the clinical features, treatment outcomes, and prognostic factors of primary NHL of the nasal cavity at early stage. METHODS: Records of 108 patients with primary NHL of the nasal cavity, consecutively treated at Cancer Center, Sun Yat-sen University from Jun. 1990 to Sep. 2004, were reviewed. All diagnoses were confirmed with pathology and immunochemistry. Seven cases were of B-cell phenotype. Survival prognostic factors were analyzed by Kaplan-Meier method and Cox regression model with SPSS12.0 software. RESULTS: Median follow-up time for survived patients was 41 months. The overall complete remission (CR) rate after primary treatment was 67.6%, and CR rates were 80.2% for the patients received radiochemotherapy and 29.6% for the patients received chemotherapy alone. There were evidences indicating systemic relapse in 33 (30.6%) patients. With regard to the control of local, regional, and systemic failure, radiochemotherapy was better than chemotherapy alone. The 5-year overall survival rate was 50.0% for all patients. Both univariate analysis and multivariate analysis showed that pre-treatment history of more than 3 months, primary lesion limited in the nasal cavity, CR after primary treatment, and radiochemotherapy were favorable prognostic factors. CONCLUSIONS: Nasal cavity is frequently involved by peripheral T- and NK-cell lymphomas. Pre-treatment history of disease, extent of primary lesion involvement, and response to the primary treatment may be independent prognostic factors.

Adolescent↗

PubMed2006

[Prognosis and treatment strategies of primary B-cell and NK/T-cell nasopharyngeal non-Hodgkin's lymphoma at early stage].

BACKGROUND & OBJECTIVE: Nasopharynx is a commonly involved site of non-Hodgkin's lymphoma (NHL), but the differences of clinical characteristics, prognosis, and treatment strategy between B-cell and NK/T-cell nasopharyngeal NHL have seldom been reported. This study was to investigate the clinical manifestations and treatment outcomes of primary B-cell and NK/T-cell nasopharyngeal NHL at early stage, and evaluate the prognostic differences, so as to provide evidences for treatment optimization. METHODS: Clinical data of 80 patients with previously untreated nasopharyngeal NHL at early stage, admitted from May 1987 to Nov. 2003, were reviewed. Of the 80 cases, 48 were B-cell original (B group), 32 were NK/T-cell original (T group). Of the 80 patients, 42 received chemoradiotherapy, 31 received chemotherapy alone, and 7 received radiotherapy alone. Most chemotherapy-treated patients received CHOP regimen (cyclophosphamide, vincristine, adriamycin, and prednisone) for 1-10 cycles (median 5 cycles). Radiotherapy was given with high energy photon beams combined with high energy electron beams in conventional fractionation, with the total dose of 30-70 Gy (median 52 Gy). Treatment patterns of the 2 groups were similar, but B group received more chemotherapy cycles than T group did. RESULTS: The 5-year overall survival rate and 5-year progression-free survival rate were significantly higher in B group than in T group (69.5% vs. 35.5%, P=0.003; 53.3% vs. 28.9%, P=0.032). Cox multivariate regression analysis suggested that B-cell phenotype, no B symptoms, and local control were independent favorable predictors of overall survival, while B-cell phenotype and good treatment response were independent favorable predictors of progression-free survival. Univariate stratified analysis with Kaplan-Meier method showed that, for B group, the cumulative 5-year overall survival rate was 68.1% in the 19 patients received chemotherapy alone, 61.7% in the 25 patients received chemoradiotherapy, and 100% in the 4 patients received radiotherapy alone (P=0.311); for T group, the cumulative 5-year overall survival rate was 0% in the 12 patients received chemotherapy alone, 44.1% in the 17 patients received chemoradiotherapy, and 33.3% in the 3 patients received radiotherapy alone (only 1 patient survived for 60 months)(P=0.020). CONCLUSIONS: Among the patients with primary nasopharyngeal NHL at early stage, those with B-cell phenotype may have better prognosis as compared with those with NK/T-cell phenotype. The patients with NK/T-cell phenotype often suffered from B symptoms, with poor response to chemotherapy. Radiotherapy or chemoradiotherapy should be more emphasized in this group of patients.

Adolescent↗

PubMed2005

Dosimetric and clinical results of three-dimensional conformal radiotherapy for locally recurrent nasopharyngeal carcinoma.

PURPOSE: To assess the dosimetric and clinical results of three-dimensional conformal radiotherapy (3D CRT) for locally recurrent nasopharyngeal carcinoma (NPC). METHODS: A total of 86 patients with locally recurrent NPC were retreated with 3D CRT. The median prescribed dose was 68 Gy with 2 Gy per fractionation. Dosimetric quality was evaluated with dose distribution in planning target volume (PTV) and specified organs at risk (OAR), dose conformity index (CI) and dose homogeneity index (HI). The actuarial rate of local failure-free (LFF), overall survival (OS) and major late toxicities (MLT) were estimated with Kaplan-Meier method. Multivariate analysis for prognosis was performed using the Cox regression proportional hazards model. RESULTS: The mean dose to PTV averaged 66.8 Gy, and the dose to specified OAR was acceptable. The average value of CI and HI was 0.59 and 9.1%. The 5-year actuarial rate of LFF and OS was 71 and 40%, respectively. The 5-year actuarial incidence of MLT>or=Grade 3 and >or=Grade 4 were 100 and 49%, respectively. The major prognostic factors were T stage and the size of gross tumor volume (GTV). Advanced T stage and large GTV volume were associated with poor LFF and OS and high risk of MLT. CONCLUSION: The dosimetric quality of 3D CRT for locally recurrent NPC is generally excellent. A relatively high local control was achieved with this technique. However, the incidence of late toxicities were not found to decrease as originally expected. Early diagnosis of the recurrence and reasonable definition of the target volume are crucial to achieve a better outcome.

Adult↗

PubMed2005

[Staging 915 cases of nasopharyngeal carcinoma after simple radical radiotherapy--checkout of Fuzhou staging system (1992)].

BACKGROUND & OBJECTIVE: Along with the development of treatments, different tumor staging systems are coexisted and have been modified. This study was to validate the rationality of the Fuzhou staging system (1992) of nasopharyngeal carcinoma (NPC), and to provide some suggestions. METHODS: A total of 915 NPC patients received radical radiotherapy alone in Cancer Center of Sun Yat-sen University from Jan. 1997 to Dec. 1998. The 1-, 3-, and 5-year follow-up rates were 98.7%, 95.2%, and 91.7%, respectively. The survival data were analyzed with Life table, Cox regression, Kaplan-Meier, and log-rank methods. RESULTS: The 1-, 3-, and 5-year overall survival rates of the 915 patients were 87.69%, 72.73%, and 64.44%; the 1-, 3-, and 5-year disease-freely survival rates were 86.87%, 69.72%, and 58.33%, respectively. Cox regression analysis showed that the 5-year survival statuses of the 915 patients were significantly correlated with their age and the tumor stage classified by the Fuzhou staging system (1992); the 5-year survival statuses of the 803 patients no more than 60 years old were only significantly correlated with tumor stage, and had no correlation with their age. Life table analysis validated that the tumor stage classified by Fuzhou staging system (1992) can roughly predict the prognosis, but the difference between the 5-year survival rates of stage I and II patients was not significant. Kaplan-Meier analysis showed no significant difference between survival statuses of stage T1 and T2 patients when adjusted by N classification. Therefore, we adjusted stage T2 without parapharyngeal space invasion to stage T1, stage T3 with carotid vagina invasion to stage T2, stage T4 with paranasal sinus involvement to stage T3, stage T3 with cranial nerve injury to stage T4, and stage N1 with bilateral lymph nodes involvement to stage N2. After the modifications, the differences among stage I to IVa, stage T1 to T4 (adjusted by N stage), or stage N0 to N3 (adjusted by T stage) were significant. CONCLUSION: Taking the impact of age on the prognosis and the interaction between T stage and N stage into consideration, the above modifications of should be included when renewing the Fuzhou staging system (1992).

Adolescent↗

PubMed2005

[Prognostic analysis of patients with nasal-type NK/T-cell non-Hodgkin's lymphoma--a report of 93 cases].

BACKGROUND & OBJECTIVE: Nasal-type NK/T-cell non-Hodgkin's lymphoma (NHL) is a unique subtype with the manifestation of local necrosis, infection and fever. The efficacy of chemotherapy alone is unsatisfactory; while radiochemotherapy plays some roles in the management of NK/T-cell lymphoma (NK/TCL). This study was to summarize the clinical characteristics, treatment outcome and prognosis of NK/TCL patients. METHODS: Records of 93 patients with NK/TCL from Jan. 1997 to Jun. 2004 were analyzed retrospectively. All the patients were classified according to WHO classification system. RESULTS: Of the 93 patients, 75 (80.6%) were in stage I-II, and 18 (19.4%) were in stage III-IV. The most common symptoms were nasal obstruction, rhinorrhea, and epistaxis. The disease course was 1-24 months with a median of 6.5 months. Of the 93 patients, 15 (16.1%) presented perforation of hard palate and/or nasal septum, 35 (37.6%) presented B symptoms; 35 (37.6%) were treated with chemotherapy alone, 2 (2.2%) were treated with radiotherapy alone, 54 (58.0%) were treated with radiochemotherapy, and 2 (2.2%) received no treatment. The first-line chemotherapy regimens were mainly CHOP and EPOCH. The overall response rate (RR) was 84.4% (76/90) with complete remission (CR) rate of 64.4% (58/90). The response rate of chemotherapy alone group was 67.6% (23/34) with CR rate of 41.2% (14/34). The response rate of combined modality group was 94.4% (51/54) with CR rate of 83.3% (45/54). The 2 patients who received no treatment died within 6 months. The major toxicity of chemotherapy was myelosuppression. The prevalence of grade III-IV neutropenia, thrombocytopenia, and anemia were 37.7%, 13.7%, and 10.7%. The major toxicities of radiotherapy were grade I-II mucosa lesion and myelosuppression. Other toxicities were mild. The mortality was 66.7% (62/93). The 1-, 3-, and 5-year overall survival (OS) rates were 63.4%, 43.1%, and 17.6%, respectively. Multivariate analysis showed that perforation of hard palate and/or nasal septum, B symptoms and therapeutic modality were independent prognostic factors of NK/TCL (P=0.035, P<0.001, and P=0.004). CONCLUSIONS: NK/TCL has low chemotherapy sensitivity. Although combined chemoradiotherapy yield better outcome, the long-term survival was still poor. Investigation of optional treatment is needed.

Adolescent↗

PubMed2005

[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. Early and late passages of normal nasopharyngeal epithelial cell line NPNE2 from nasopharyngeal biopsy specimens, immortalized nasopharyngeal epithelial cell line NP69SV40T, nasopharyngeal carcinoma (NPC) cell line SUNE-1 and its high metastatic subclone 5-8F were cultured in Matrigel to establish three-dimensional models. RESULTS: The cells grew out of non-tumor nasopharyngeal biopsy specimens displayed the morphologic characteristics as epithelia, and could proliferate in vitro for 8-10 passages before senescence. Immunocytochemical staining of cytokeratin revealed that the cells were of epithelial origin. All of the cells, except late passages of NPNE2 cells, could proliferate in the three-dimensional culture system. NPNE2 and NP69SV40T cells mainly developed reticular structures in morphology, and formed few clones with clear and smooth edges as well as tight intercellular junctions. SUNE-1 and 5-8F cells formed clones with irregular morphology, unclear edge, and loose intercellular junctions. In addition, the clones formed by 5-8F cells also developed a lot of pseudopodia, but developed no reticular structure. Late passages of NPNE2 cells formed no clone and reticular structure in the three-dimensional culture. CONCLUSIONS: Normal nasopharyngeal epithelial cells can be successfully cultured in vitro from naspharyngeal biopsy specimens. The three-dimensional culture models, established with normal nasopharyngeal epithelial cells, immortalized nasopharyngeal epithelial cells, and NPC cells, may represent the different stages of nasopharyngeal carcinogenesis.

Cell Culture Techniques↗

PubMed2005

[Quality of life of 192 disease-freely survival nasopharyngeal carcinoma patients after radiotherapy].

BACKGROUND & OBJECTIVE: With the elevation of survival rate of nasopharyngeal carcinoma (NPC) patients after treatment, their quality of life (QOL) is more and more emphasized. This study was designed to evaluate the QOL of disease-freely survival NPC patients after treatment, and to investigate the factors correlated with their QOL. METHODS: From Jul. to Aug. 2003, disease-freely survival NPC patients who had been treated from 1999 to 2000 in Cancer Center of Sun Yat-sen University were enrolled. The Chinese SF-36 questionnaire and a checklist consists of 14 items about self-rating symptoms were self-reported by all participants at clinic. Sociodemographic and clinical data of the patients were also collected, and their relationships with SF-36 data and symptoms were analyzed. RESULTS: A total of 192 patients were enrolled in the study. The median survival time was 3.6 years (ranged 2.4-4.6 years). Xerostomia was the first common symptom, followed by hypoacusis, hypomnesia, dysphagia, and trismus. Univariate analysis showed that gender, age, educational level, monthly income, economic status, religion, and the number of complications had influences on QOL; the patients in earlier T and N stages, irradiated by linear accelerator, with lower total dose and weekly dosage to the nasopharynx and neck, and those who had anterior nasal field radiation reported better QOL. Multiple stepwise regression analysis showed that the number of complications, monthly income, age, and T stage were independent factors affecting total QOL. CONCLUSIONS: Improving radiotherapy might enhance physical functions of NPC patients. The prevention and control of chronic diseases, the development of economy, and the increase of income may promote NPC patients' QOL.

Adolescent↗

PubMed2004

Aloe polysaccharides mediated radioprotective effect through the inhibition of apoptosis.

Polysaccharides from aloe are always considered an effective radioprotector on irradiation-induced skin damage. The aim of this study was to determine if aloe polysaccharides (AP) have radioprotective effects on normal human cells in vitro and mouse survival in vivo and to explore the mechanism. Pretreatment with 50 microg/ml AP could improve the surviving fraction at 2 Gy (SF2) of three normal cell lines 293, ECV304, and C. liver from 41.5%, 46.5%, and 40.9% to 49.4%, 72.1%, and 89.1%, respectively. AP could also reduce the apoptotic rate of C. liver cells from 9.5% and 43.0% to 2.2% and 10.9% 48 h and 72 h after 2 Gy irradiation, respectively. Western blot analysis showed that pretreatment with AP could block the upregulation of pro-apoptotic p53, Bax, and Bad and the downregulation of Bcl-2 by irradiation. AP could lower thymocyte apoptosis of mice in vivo after 6 Gy irradiation and abrogate the cell cycle perturbation. Fifty mg/kg of AP treatment for 30 min before 7.5 Gy irradiation provided the best radioprotective effect and improved the 30-day survival rate of mice to 86.0%, from 10.0%. AP exerted radioprotective effects in vitro and in vivo through an inhibition of apoptosis.

Aloe↗

PubMed2004

[Influence of vacuum bag on direct measurement of depth for isocentric posterior oblique field].

BACKGROUND & OBJECTIVE: In order to improve quality assurance (QA) and quality control (QC) of radiotherapy, individualized vacuum bag is used in the localization of radiation treatment, gradually becoming one of the important steps for the QA and QC in the many departments of radiation oncology. It is controversial whether localization with vacuum bags under the simulator influences the precision of direct measurement for tumor depth in the isocentric posterior oblique field in the patients with thoracic and abdominal tumors. This study was designed to explore the influence of vacuum bag on the direct measurement METHODS: Twenty-nine patients with thoracic and abdominal carcinoma who had to need isocentric irradiation in the supine position were immobilized using vacuum bag. The irradiation depths of 45 posterior oblique fields were determined by CT-simulator and conventional simulator, respectively; then the absolute value for the difference of both depths was regarded as error value. RESULTS: There were 37 fields (82.2%) with error value of smaller than 5 mm; 8 fields (17.8%), more than 5 mm. In the latter, 5 field were belonged to be repositioned in the phase II of radiotherapy because of light leaking air into the vacuum bag in the phase I of radiotherapy. CONCLUSION: Vacuum bag has a slight influence on direct measurement for depths of isocentric posterior oblique field.

Adolescent↗

PubMed2004

[ATM and telomere instability].

Accumulation of DNA damage has been associated with the onset of senescence and the predisposition to cancer. The gene responsible for ataxia telangiectasia (A-T) is ATM (Ataxia-telangiectasia mutant), a master controller of cellular pathways and networks, orchestrating the response to a specific type of DNA damage, i.e., the double strand break. It has now been demonstrated that mutations in ATM lead to defective telomere maintenance in mammalian cells. This review will focus on its roles in telomere metabolism and how ATM and telomeres serve as controllers of cellular responses to DNA damage.

Ataxia Telangiectasia↗

PubMed2003

[Expression of ATM protein in nasopharyngeal carcinoma cell lines with different radiosensitivity].

BACKGROUND & OBJECTIVE: It has been reported that ataxia- telangiectasia mutant(ATM) protein is closely correlated with cellular radiosensitivity in several malignant tumors. This study was designed to determine the expression of ATM protein in two nasopharyngeal carcinoma (NPC) cell lines with different radiosensitivity. METHODS: Two NPC cell lines, CNE1 and CNE2, with different radiosensitivity were established. The localization and quantity of ATM protein were analyzed by fluorescence immunohistochemical method and laser scanning confocal microscope(LSCM). RESULTS: ATM protein was located in both karyon and cytoplasm, especially strongly expressed in karyon. The intense fluorescence of ATM protein was stronger in karyon of CNE1 than that in CNE2. CONCLUSION: The expression levels of ATM protein differ in CNE1 and CNE2. The variance may be a potential factor, which links with their different radiosensitivity.

Ataxia Telangiectasia Mutated Proteins↗