MAGI1-IT1 stimulates proliferation in non-small cell lung cancer by upregulating AKT1 as a ceRNA.

OBJECTIVE: This study aims to illustrate the potential role of MAGI1-IT1 in the progression of non-small cell lung cancer (NSCLC) and the underlying mechanism. PATIENTS AND METHODS: The relative level of MAGI1-IT1 in normal lung tissues and NSCLC tissues was determined. Its level in NSCLC patients with different tumor sizes (<5 cm or >5 cm), metastatic statues (positive or negative), and tumor staging (stage I+II or stage III+IV) was detected as well. The prognostic potential of MAGI1-IT1 in evaluating the overall survival (OS) and progression-free survival (PFS) of NSCLC patients was assessed by the Kaplan-Meier method. In A549 and PC-9 cells, the regulatory effect of MAGI1-IT1 on the proliferative ability was examined by the cell counting kit-8 (CCK-8), colony formation, and 5-Ethynyl-2'-deoxyuridine (EdU) assay. The target miRNA of MAGI1-IT1 and the target gene binding to miRNA-512-3p were predicted using the Diana database. The interactions among MAGI1-IT1/miRNA-512-3p/AKT1 regulatory loop were tested by the Dual-luciferase reporter gene assay and RNA immunoprecipitation (RIP) assay. At last, the rescue experiments were carried out to uncover the regulatory effect of MAGI1-IT1/AKT1 axis on NSCLC progression. RESULTS: MAGI1-IT1 was upregulated in NSCLC tissues. Its level was higher in NSCLC patients with larger tumor size, positive metastasis, or advanced stage. High level of MAGI1-IT1 predicted worse OS and PFS in NSCLC patients. The knockdown of MAGI1-IT1 remarkably attenuated the proliferative ability in A549 and PC-9 cells. MAGI1-IT1 could target miRNA-512-3p, and AKT1 was the target gene of miR-512-3p. The overexpression of AKT1 stimulated lung cancer cells to proliferate. Of note, the elevated proliferative rate in lung cancer cells overexpressing AKT1 was reversed by the silence of MAGI1-IT1. CONCLUSIONS: MAGI1-IT1 is upregulated in NSCLC tissues and cell lines, and predicts a poor prognosis in NSCLC patients. MAGI1-IT1 stimulates proliferative ability in NSCLC by upregulating the AKT1 level by binding to miRNA-512-3p.

[Brain derived neurotrophic factor enhances the role of mesenchymal stem cells in inhibiting follicular helper T cells].

Objective: To investigate the effect of brain derived neurotrophic factor (BDNF) on mesenchymal stem cells (MSC) inhibiting follicular helper T cells (Tfh cells). Methods: The contents of indoleamine 2,3-dioxygenase (IDO), IL-10, TGF-ß and IL-21 in MSC culture supernatant were detected by ELISA; The peripheral blood of healthy volunteers were collected, and lymphocyte in peripheral blood was separated by human lymphocyte separation solution; Co-cultures of MSC and lymphocyte were performed by Transwell chamber, and the proportion of CD4(+)CXCR5(+) Tfh cells and their subtypes were detected by flow cytometry. Results: ①The concentrations of IL-10, TGF-ß, and IDO in the supernatant of BDNF group (BDNF-stimulated MSC) were higher than those of the control ones (adding PBS with the same volume) [IL-10: (42.1±4.4) ng/ml vs (19.3±2.1) ng/ml, t=4.761, P=0.009; TGF-ß: (13.9±1.7) ng/ml vs (5.3±0.6) ng/ml, t=5.129, P=0.008; IDO: (441.3±56.9) ng/ml vs (226.7±37.6) ng/ml, t=3.130, P=0.035]; ②The comparisons between BDNF (co-culture of lymphocyte and BDNF-stimulated MSC) and MSC groups (co-culture of lymphocyte and MSC) were detailed as of follows: the proportion of CD4(+) CXCR5(+)Tfh cells were lower [(3.37±0.21)% vs (6.51±0.27)%, t=9.353, P<0.001], the proportion of CD4(+) CXCR5(+)CXCR3(+) CCR6(-) Tfh cells were higher [(41.14±2.04)% vs (26.72±2.57)%, t=4.383, P=0.012], CD4(+)CXCR5(+)CXCR3(-)CCR6(-) Tfh2 cells and CD4(+)CXCR5(+)CXCR3(-)CCR6(+) Tfh17 cells were lower [Tfh2: (30.16±5.38)% vs (43.26±4.11)%, t=4.426, P=0.012; Tfh17: (15.61±1.52)% vs (22.32±0.72)%, t=4.202, P=0.014], the proportion of CD4(+)CXCR5(+)Foxp3(+) Tfr cells were higher [(4.95±0.22)% vs (2.32±0.16)%, t=10.241, P<0.001], the concentration of IL-21 in the lymphocyte supernatant was lower [(0.28±0.03) ng/ml vs (0.85±0.08) ng/ml, t=6.675, P=0.003]. Conclusion: BDNF could enhance the inhibitory effect of MSC on Tfh cells through inhibiting the increasing of Tfh cells and the differentiations of Tfh2 and Tfh17 cells.

Immunohistochemical studies and fluorodeoxyglucose uptake on positron emission tomography in pharyngeal cancer for predicting radiotherapy-based treatment outcomes.

OBJECTIVES: This study correlated immunohistochemical studies with fluorodeoxyglucose (FDG) uptake on positron emission tomography-computed tomography (PET-CT) and identified prognostic factors for radiotherapy (RT)-based treatment outcomes in patients with squamous cell carcinoma of the oropharynx and hypopharynx. METHODS: Genomic data from pre-treatment biopsy specimens (Glut1, CAIX, VEGF, HIF-1α, EGFR, Ki-67, Bcl-2, CLAUDIN-4, YAP-1, c-Met and p16) of 76 patients were analysed using tissue microarrays. FDG uptake was evaluated using the maximum standardised uptake value (SUVmax), metabolic tumour volume (MTV) and total lesion glycolysis (TLG). RESULTS: The overexpression of Glut1 positively associated with increased values of the SUVmax, MTV and TLG, whereas VEGF and HIF-1α expression with the MTV and TLG, respectively. A VEGF immunoreactive score (IRS) >2 (P = 0.001, hazard ratio [HR] = 3.94) and an MTV defined by an SUV of 2.5 (MTV2.5) >14.5 mL (P = 0.004, HR = 3.31) were prognostic factors for low cause-specific survival, whereas a VEGF IRS >2 (P = 0.02, HR = 2.83) for low primary relapse-free survival. CONCLUSION: The overexpression of Glut1, VEGF and HIF-1α associated with increased FDG uptake. For patients with pharyngeal cancer requiring RT, the treatment outcome can be stratified by VEGF and MTV2.5.

Gambogic acid synergistically potentiates cisplatin-induced apoptosis in non-small-cell lung cancer through suppressing NF-κB and MAPK/HO-1 signalling.

BACKGROUND: Gambogic acid (GA) has been reported to have potent anticancer activity and is authorised to be tested in phase II clinical trials for treatment of non-small-cell lung cancer (NSCLC). The present study aims to investigate whether GA would be synergistic with cisplatin (CDDP) against the NSCLC. METHODS: 1-(4,5-Dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT), combination index (CI) isobologram, western blot, quantitative PCR, flow cytometry, electrophoretic mobility shift assay, xenograft tumour models and terminal deoxynucleotide transferase-mediated dUTP nick-end labelling analysis were used in this study. RESULTS: The cell viability results showed that sequential CDDP-GA treatment resulted in a strong synergistic action in A549, NCI-H460, and NCI-H1299 cell lines, whereas the reverse sequence and simultaneous treatments led to a slight synergistic or additive action. Increased sub-G1 phase cells and enhanced PARP cleavage demonstrated that the sequence of CDDP-GA treatment markedly increased apoptosis in comparison with other treatments. Furthermore, the sequential combination could enhance the activation of caspase-3, -8, and 9, increase the expression of Fas and Bax, and decrease the expression of Bcl-2, survivin and X-inhibitor of apoptosis protein (X-IAP) in A549 and NCI-H460 cell lines. In addition, increased apoptosis was correlated with enhanced reactive oxygen species generation. Importantly, it was found that, followed by CDDP treatment, GA could inhibit NF-κB and mitogen-activated protein kinase (MAPK)/heme oxygenase-1 (HO-1) signalling pathways, which have been validated to reduce ROS release and confer CDDP resistance. The roles of NF-κB and MAPK pathways were further confirmed by using specific inhibitors, which significantly increased ROS release and apoptosis induced by the sequential combination of CDDP and GA. Moreover, our results indicated that the combination of CDDP and GA exerted increased antitumour effects on A549 xenograft models through inhibiting NF-κB, HO-1, and subsequently inducing apoptosis. CONCLUSION: Gambogic acid sensitises lung cancer cells to CDDP in vitro and in vivo in NSCLC through inactivation of NF-κB and MAPK/HO-1 signalling pathways, providing a rationale for the combined use of CDDP and GA in lung cancer chemotherapy.

High case volume of radiation oncologists is associated with better survival of nasopharyngeal carcinoma patients treated with radiotherapy: a multifactorial cohort analysis.

OBJECTIVES: The relationship between physician case volume and patient outcome in patients with head and neck cancers such as nasopharyngeal carcinoma treated by radiotherapy is unknown. This study was designed to investigate the association between the case volume of radiation oncologists and the survival of patients with nasopharyngeal carcinoma. DESIGN: Retrospective cohort study. SETTING: Based on nationwide claims data (National Health Research Insurance Database) in the years 2002-2008. PARTICIPANTS: Newly diagnosed patients with nasopharyngeal carcinoma receiving curative radiotherapy in the year 2003. MAIN OUTCOME MEASURES: Overall survival until 2008. We used the running log-rank test to decide the optimal threshold for categorising the case volume of radiation oncologists. The characteristics of patients, their treatments and contact with health service providers were considered as co-explanatory variables. The log-rank test and Cox regression were performed. Sensitivity analyses were carried out regarding major study assumptions. RESULTS: Five hundred and sixty-two patients with nasopharyngeal carcinoma newly diagnosed in 2003 were identified as the study cohort. The 5-year overall survival was better among patients treated by high-volume (≥6 patients in year 2002) radiation oncologists than by low-volume (<6 patients in year 2002) radiation oncologists (77%versus 64%, P = 0.0007). The adjusted hazard ratio of death was 0.65 (95% confidence interval, 0.48-0.91) upon multivariate analysis. Patients aged at least 65 years also had a lower survival rate than those younger than 65 years old (adjusted hazard ratio of death: 2.81, 95% confidence interval: 1.94-4.08).The physician case volume and patient outcome effect remained the same after sensitivity analyses. CONCLUSIONS: Patients with nasopharyngeal carcinoma treated by high-volume radiation oncologists have better survival compared with those treated by low-volume radiation oncologists. Further studies are needed to verify our findings with similar cancer cohorts treated by modern radiotherapy techniques or other types of radiotherapy.

Late toxicities in concurrent chemoradiotherapy using high-dose-rate intracavitary brachytherapy plus weekly cisplatin for locally advanced cervical cancer: a historical cohort comparison against two previous different treatment schemes.

PURPOSE: To determine the long-term toxicity of concurrent chemoradiotherapy (CCRT), using high-dose rate intracavitary brachytherapy (HDRICB) compared to radiation (RT) alone in patients with advanced cervical cancer using a control-cohort study. METHODS: A total of 332 cases of Stage IIB-III disease were included in this comparative study. Seventy-three patients were treated with a 3-insertion schedule and labeled group A, whereas the other 146 patients with a 4-insertion schedule became group B. One hundred and thirteen patients treated by a 4-insertion protocol with concurrent weekly cisplatin were labeled group C. RESULTS: The cumulative rate of grade 2 or above rectal complication was 13.7% for group A, 9.6% for the group B and 15.9% for group C (p = 0.76), whereas the grade 3 to 4 non-rectal radiation-induced intestinal injury was 6.8% for group A, 6.2% for group B and 9.7% for group C (p = 0.20). Grade 2 to 4 late bladder toxicity was higher in group C, with the cumulative rate being 5.5% for group A, 4.8% for group B and 15.0% for group C (p = 0.004). The independent factor for a rectal complication was the occurrence of a bladder complication (p = 0.01, hazard ratio 3.06). The independent factors for bladder complications were the use of CCRT (p = 0.01, hazard ratio 2.08), and the occurrence of rectal complications (p = 0.02, hazard ratio 2.77). CONCLUSIONS: When treating advanced cervical cancer, HDRICB consisting of four 6 Gy insertions and weekly cisplatin shows a trend of increasing late bladder complications. The interval between drug administration and HDRICB should be kept long enough to avoid any synergistic effect of both regimens.

The outcome and prognostic factors in patients with aspiration pneumonia during concurrent chemoradiotherapy for head and neck cancer.

This study aimed to investigate the outcome in patients with aspiration pneumonia during definitive concurrent chemoradiotherapy for head and neck cancer. The data of 595 patients with head and neck cancer treated by chemoradiotherapy were reviewed. Forty-one patients were identified as developing symptomatic aspiration pneumonia during treatment and were analysed for this study. The definition of symptomatic aspiration pneumonia fit three criteria: (1) at least one event of aspiration during the treatment or evidence of grade 2 or above dysphagia during treatment; (2) clinical or radiographic signs of pneumonia or pneumonitis; and (3) no evidence of grade 4 haematological toxicity before the outbreak of pneumonia. Termination of allocated radiotherapy was noted in 10 patients. A treatment break was observed in 26 patients, whereas irradiation was prolonged more than 1 week in 11 patients. Logistic regression analysis showed the dysphagia score during the treatment course and the chest roentgenography pattern following symptomatic aspiration pneumonia were found to independently influence the outcome. Aspiration pneumonia occurring during chemoradiotherapy for head and neck cancer has a detrimental effect on the treatment outcome. Intensive medical care is essential for this group of patients with a dysphagia score of 3 during treatment and an unfavourable chest film pattern.

Hypopharyngeal cancer treatment based on definitive radiotherapy: who is suitable for laryngeal preservation?

AIMS: To investigate prognostic factors for survival and locoregional control in patients with stage I-IVA hypopharyngeal cancer treated with laryngeal preservation radiotherapy. METHODS: This study was a retrospective analysis of 108 patients with stage I-IVA squamous cell carcinoma of the hypopharynx, treated with laryngeal preservation radiotherapy. Actuarial survival, disease-specific survival and local relapse-free survival were calculated, and multivariate analyses were performed using Cox's proportional hazards model. RESULTS: After a median follow-up duration of 39 months, the five-year local relapse-free survival rate was 35 per cent for all patients, 66 per cent for those with stage I-II disease, 46 per cent for those with stage III disease and 20 per cent for those with stage IVA disease (p = 0.004). Multivariate analyses showed that tumour and node stages were independent prognostic factors. CONCLUSIONS: Patients with stage I-II disease were suitable for laryngeal preservation radiotherapy. For most patients with stage III-IVA disease, other than those who were T1 N1 or T2 N1, the treatment results were poor.

Early stage cervical cancer with negative pelvic lymph nodes: pattern of failure and complication following radical hysterectomy and adjuvant radiotherapy.

PURPOSE OF INVESTIGATION: The objective was to optimize the adjuvant treatment for patients with lymph node negative cervical cancer by analyzing patterns of failure and complications following radical hysterectomy and adjuvant radiotherapy. METHODS: From September 1992 to December 1998, 67 patients with lymph node negative uterine cervical cancer (FIGO stage distribution: 50 Ib. 17 IIa), who had undergone radical hysterectomy and postoperative adjuvant radiotherapy with a minimum of three years of follow-up were evaluated. All patients received 50-58 Gy of external radiation to the lower pelvis followed by two sessions of intravaginal brachytherapy with a prescribed dose of 7.5 Gy to the vaginal mucosa. For 21 patients with lymphovascular invasion, the initial irradiation field included the whole pelvis for 44 Gy. The data were analyzed for actuarial survival (AS), pelvic relapse-free survival (PRFS), distant metastasis-free survival (DMFS), and treatment-related complications. Multivariate analysis was performed to assess the prognostic factors. RESULTS: The respective five-year AS, PRFS, and DMFS for the 67 patients were 79%, 93% and 87%. Multivariate analysis identified two prognostic factors for AS: bulky tumor vs non-bulky tumor (p = 0.003), positive resection margin (p = 0.03). The independent prognostic factors for DMFS was bulky tumor (p = 0.003), while lymphatic permeation showed marginal impact to DMFS (p = 0.08). The incidence of RTOG grade 1-4 rectal and non-rectal gastrointestinal complication rates were 20.9% and 19.4%, respectively. The independent prognostic factor for gastrointestinal complication was age over 60 years (p = 0.047, relative risk 4.1, 95% CI 1.2 approximately 11.7). The incidence of non-rectal gastrointestinal injury for the patients receiving whole pelvic radiation and lower pelvic radiation was 28.5% and 15.2%, respectively (p = 0.25). CONCLUSION: For patients with lymph node negative cervical cancer following radical hysterectomy, adjuvant lower pelvic radiation appears to be effective for pelvic control. It is also imperative to intensify the strategies of adjuvant therapy for some subgroups of patients.

Comparing whole body (18)F-2-deoxyglucose positron emission tomography and technetium-99m methylene diphosphonate bone scan to detect bone metastases in patients with breast cancer.

PURPOSE: At present, bone metastases are usually assessed using conventional technetium-99m methylene diphosphonate whole-body bone scan, which has a high sensitivity but a poor specificity. However, positron emission tomography with (18)F-2-deoxyglucose (FDG-PET) can offer superior spatial resolution and improved specificity. We attempted to evaluate the usefulness of FDG-PET for detecting bone metastases in breast cancer and to compare FDG-PET results with bone scan findings. PATIENTS: The study group comprised 48 patients with biopsy-proven breast cancer and suspected of having bone metastases who underwent bone scan and FDG-PET to detect the bone metastases. The final diagnosis of bone metastases was established by operative, histopathological findings or during a clinical follow-up longer than 1 year by additional radiographs or following FDG-PET/bone scan findings showing progressive widespread bone lesions. RESULTS: A total of 127 bone lesions including 105 metastatic and 22 benign bone lesions found by either FDG-PET or bone scan were evaluated. Using FDG-PET, 100 metastatic and 20 benign bone lesions were accurately diagnosed, and using bone scan 98 metastatic and 2 benign bone lesions were accurately diagnosed. The diagnostic sensitivity and accuracy of FDG-PET were 95.2% and 94.5%, and of bone scan were 93.3% and 78.7%, respectively. CONCLUSIONS: Our findings suggest that FDG-PET shows a similar sensitivity and a better accuracy than bone scan for detecting bone metastases in patients with breast cancer.

Retrospective comparison of the AJCC 5th edition classification for nasopharyngeal carcinoma with the AJCC 4th edition: an experience in Taiwan.

OBJECTIVE: The aim of this study was to compare the new AJCC 5th edition classification system for nasopharyngeal carcinoma (NPC) with the AJCC 4th edition by re-evaluating the staging of patients treated in Taiwan. METHODS: From 1992 through 1996, 117 NPC patients without distant metastasis were treated using complete courses of radiotherapy. All patients had complete CT examinations of the nasopharynx and neck. Each patient was re-staged according to the 5th edition of the AJCC classification system. Their overall survival (OS), loco-regional relapse-free survival (LRRFS), distant metastasis-free survival (DMFS) and disease-free survival (DFS) were compared between the two staging systems, using the Kaplan-Meier method, log-rank test, Wilcoxon test and Cox proportional hazard model. RESULTS: After a median follow-up of 58.3 months, the 5-year OS for stage I, II, III and IV was 88, 86, 61 and 48%, respectively, according to the new staging. A more even distribution of patients was noted among the patients classified according to the AJCC 5th edition than the 4th edition. The distribution of stages I, II, III and IV was 13.7, 37.6, 15.4 and 33.3%, respectively, using the new staging system, whereas it was 0.8, 14.5, 20.5 and 64.2%, respectively, using the old staging system. More statistically significant differences among 5th edition stages and T classifications than the 4th edition were also noted. CONCLUSIONS: The 5th edition of the AJCC staging system appears to have a more even distribution of patients and more statistically significant differences in predicting prognosis than the 4th edition, mostly in stages and T classification.

Inositol hexakisphosphate increases L-type Ca2+ channel activity by stimulation of adenylyl cyclase.

Inositol hexakisphosphate (InsP6) is a most abundant inositol polyphosphate that changes simultaneously with inositol 1,4,5-trisphosphate in depolarized neurons. However, the role of InsP6 in neuronal signaling is unknown. Mass assay reveals that the basal levels of InsP6 in several brain regions tested are similar. InsP6 mass is significantly elevated in activated brain neurons and lowered by inhibition of neuronal activity. Furthermore, the hippocampus is most sensitive to electrical challenge with regard to percentage accumulation of InsP6. In hippocampal neurons, InsP6 stimulates adenylyl cyclase (AC) without influencing cAMP phosphodiesterases, resulting in activation of protein kinase A (PKA) and thereby selective enhancement of voltage-gated L-type Ca2+ channel activity. This enhancement was abolished by preincubation with PKA and AC inhibitors. These data suggest that InsP6 increases L-type Ca2+ channel activity by facilitating phosphorylation of PKA phosphorylation sites. Thus, in hippocampal neurons, InsP6 serves as an important signal in modulation of voltage-gated L-type Ca2+ channel activity.

Femtomolar concentrations of dynorphins protect rat mesencephalic dopaminergic neurons against inflammatory damage.

The hallmark of Parkinson's disease is the death of nigral dopaminergic neurons, and inflammation in the brain has been increasingly associated with the pathogenesis of this neurological disorder. Dynorphins are among the major opioid peptides in the striato-nigral pathway and are important in regulating dopaminergic neuronal activities. However, it is not clear whether dynorphins play a role in the survival of nigral dopaminergic neurons. We have recently demonstrated that lipopolysaccharide (LPS) activates the brain immune cells microglia, in vitro and in vivo, to release neurotoxic factors to degenerate dopaminergic neurons. The purpose of this study was to explore the neuroprotective effect of dynorphins in the inflammation-mediated degeneration of dopaminergic neurons in rat midbrain neuron-glia cultures. LPS-induced neurotoxicity was significantly reduced by treatment with ultra low concentrations (10(-13)--10(-15) M) of the kappa-opioid receptor agonist dynorphin A (1--17) or the receptor binding ineffective [des-Tyr(1)]dynorphin A (2--17), but not by U50488, a synthetic kappa-receptor agonist. The glia-mediated neuroprotective effect of dynorphins was further supported by the finding that femtomolar concentrations of dynorphins did not prevent the killing of dopaminergic neurons by 6-hydroxydopamine. However, ultra low concentrations of dynorphins inhibited LPS-induced production of superoxide. These results suggest a glia-mediated and conventional opioid receptor-unrelated mechanism of action for the neuroprotective effect of ultra low concentrations of dynorphins. Understanding the underlying mechanisms of action should further define the roles of dynorphins in the regulation of dopaminergic neurons and help devise novel strategies to combat neurodegenerative diseases.

Intra-thoracic failure pattern and survival status following 3D conformal radiotherapy for non-small cell lung cancer: a preliminary report.

BACKGROUND: To study the intra-thoracic failure pattern, clinical target volume (CTV) and survival status following 3D conformal radiotherapy (3DCRT) boost for non-small cell lung cancer (NSCLC). METHODS: From May 1994 through June 1998, 33 patients (26 male, seven female) with NSCLC were treated with a complete course of radiotherapy (RT) in our institute. Group A included 10 patients receiving radical operation and adjuvant postoperative RT. The other 23 patients (groups B and C) received definitive radiotherapy as local treatment. Among them there were seven cases as group B (stage I-II) and 16 cases as group C (stage III). Fifteen (15/33) patients received chemotherapy. The radiotherapy strategy constituted conventional AP/PA radiotherapy (RT) 19.8-45 Gy (median 39.6 Gy) plus 3DCRT boost 6-34.2 Gy (median 20 Gy). The median total tumor dose was 59.6 Gy (ranging from 39.8 to 64.8 Gy). Patients were followed up regularly (6/33) or until their death (27/33). Nineteen patients received follow-up chest computed tomography (CT). The relationship between intra-thoracic failure found by chest CT and the initial RT and boost RT fields was analyzed. Local failure was defined as one of the following: clinical disease progression, CXR progression or relapse noted by CT. The overall survival (OS) and local failure free survival (LFF) were obtained using the Kaplan-Meier method. RESULTS: Sixteen intra-thoracic failures were noted in 15 follow-up chest CT examinations, which included nine in-field relapses, three partial in-field relapses and four out-field relapses. The 2-year OS and LFF for groups A, B and C were 78.8/59.2, 14.2/16.7 and 6.2/7.1% respectively. RTOG grade III/IV complications included one pneumothorax (RTOG grade III). CONCLUSION: Our retrospective study showed that selective omission of contralateral mediastinal lymph node station irradiation may be appropriate in RT for NSCLC. Chest wall and pleural relapses may not be a negligible cause of intra-thoracic failure after RT for NSCLC.

Differentiating benign and malignant pulmonary lesions with FDG-PET.

The purpose of this retrospective study was to evaluate the efficacy of positron emission tomography (PET) with 18F-fluoro-2-deoxyglucose (FDG) to differentiate benign from malignant pulmonary lesions. Fifty-five patients, suspected of having primary pulmonary neoplasm based on chest radiographic findings, underwent FDG-PET scanning. Pathological diagnoses were obtained in 41 patients with a total of 43 pulmonary lesions. The other 14 patients (14 lesions) were followed-up clinically for at least four months. The standard uptake value (SUV) was determined in each patient. The SUV of the 15 benign and 40 malignant pulmonary lesions were 1.60+/-0.42 and 6.14+/-2.67, respectively. If SUV was > 2.50, the pulmonary lesion was considered as a malignant pulmonary lesion. FDG-PET could correctly detect 34 true-positive and 15 true-negative pulmonary lesions. However, 6 false-positive and one-false negative pulmonary lesions were misdiagnosed by FDG-PET. The sensitivity, specificity and accuracy of FDG-PET to differentiate between benign and malignant pulmonary lesions were 94%, 71% and 86%, respectively. FDG-PET can accurately detect malignant pulmonary lesions with a high sensitivity. However, false-positive FDG-PET findings caused by some inflammatory processes may decrease its specificity.

Munc-18 associates with syntaxin and serves as a negative regulator of exocytosis in the pancreatic beta -cell.

The Munc-18 protein (mammalian homologue of the unc-18 gene; also called nSec1 or rbSec1) has been identified as an essential component of the synaptic vesicle fusion protein complex. The cellular and subcellular localization and functional role of Munc-18 protein in pancreatic beta-cells was investigated. Subcellular fractionation of insulin-secreting HIT-T15 cells revealed a 67-kDa protein in both cytosol and membrane fractions. Immunohistochemistry showed punctate Munc-18 immunoreactivity in the cytoplasm of rat pancreatic islet cells. Direct double-labeling immunofluorescence histochemistry combined with confocal laser microscopy revealed the presence of Munc-18 immunoreactivity in insulin-, glucagon-, pancreatic polypeptide-, and somatostatin-containing cells. Syntaxin 1 immunoreactivity was detected in extracts of HIT-T15 cells, which were immunoprecipitated using Munc-18 antiserum, suggesting an intimate association of Munc-18 with syntaxin 1. Administration of Munc-18 peptide or Munc-18 antiserum to streptolysin O-permeabilized HIT-T15 cells resulted in significantly increased insulin release, but did not have any significant effect on voltage-gated Ca(2+) channel activity. The findings taken together show that the Munc-18 protein is present in insulin-secreting beta-cells and implicate Munc-18 as a negative regulator of the insulin secretory machinery via a mechanism that does not involve syntaxin-associated Ca(2+) channels.

The prediction of late rectal complications following the treatment of uterine cervical cancer by high-dose-rate brachytherapy.

PURPOSE: This study aimed to correlate patient, treatment, and dosimetric factors with the risk of late rectal sequelae in patients with uterine cervical cancer treated with external beam radiation therapy (EBRT) and high dose rate intracavitary brachytherapy (HDRICB). METHODS AND MATERIALS: From September 1992 to December 1995, a total of 128 patients with uterine cervical cancer, who were treated and survived more than 12 months, were evaluated. After EBRT with 40-44 Gy/20-22 Fr/4-5 weeks to the whole pelvis, the dose was boosted up to 54-58 Gy with central shielding for patients with bilateral parametria of Stage IIb or greater. HDRICB consisted of three to four insertions at doses of 5-7.2 Gy (to Point A) at intervals of 1 week. Patient and treatment factors were analyzed using logistic regression analysis and the cumulative rectal biologic equivalent dose (CRBED) was calculated. RESULTS: After 30-75 months of follow-up (median, 43 months), 38 patients (29.7%) had late rectal sequelae. Patients who had Stage IIb-IVa disease, cumulative rectal dose (external RT + total ICRU rectal dose) greeater than 65 Gy, or age greater than 70 years had a high risk of developing late rectal sequelae. When 110 Gy was used as the cut-off value, 19.6% (10 of 51) of patients whose CRBED was less than 110 Gy had rectal complications, while 36.4% (28/77) of patients whose CRBED was greater than 110 Gy developed rectal complications. CONCLUSION: Risk factors of late rectal complications were advanced stage, age greater than 70 years, and cumulative rectal dose of greater than 65 Gy.