Disclosing Potential Therapeutic Targets Associated With Osimertinib Resistance in the Non-small Cell Lung Cancer Cell Line H1975.

BACKGROUND/AIM: Osimertinib, a third-generation epidermal growth factor receptor tyrosine kinase inhibitor, is a highly effective and valuable treatment option for advanced non-small cell lung cancer (NSCLC) patients with EGFR mutations, such as T790M. However, acquired resistance ultimately limits its clinical application. In this study, we aimed to identify potential targets for overcoming osimertinib resistance. MATERIALS AND METHODS: The H1975/OSI cell line was induced in vitro through intermittent induction. Cell activity was measured using a cell counting kit-8 assay. Uni-omics and multi-omics analyses were conducted on the transcriptomic and proteomic (4D label-free) expression profiles, which involved differential expression analysis, GO functional annotation and KEGG pathway enrichment analysis, as well as correlation analysis of transcription factors and PPI network. RESULTS: H1975/OSI cells showed resistance towards osimertinib with IC50 values approximately 5.25-fold higher than H1975 cells. A total of 2519 genes were found to be differentially expressed genes (DEGs) and 1533 proteins were found to be differentially abundant proteins (DAPs). Furthermore, 147 genes that were differentially expressed at both the transcription and protein levels (TPGs) were identified as being differentially expressed in both the transcriptome and proteome. It was revealed that many pathways related to the structure and function of ribosomes, as well as metabolites, were altered. The highest connectivity genes of 147 TPGs included NOP56, DDX21, PDCD11, CCNB1, and TOP2A. The hub genes of the transcriptional regulatory network included DDX21, KPNA2, DDX5, BRCA1, LMNB1, and HIF1A. CONCLUSION: Collectively, our high-throughput analysis uncovered functional properties that interacted with gene signatures of H1975/OSI cells, and highlighted certain pathways and eleven hub genes that may be the potential targets for improving clinical osimertinib resistance.

Corporate Co-Agglomeration and Green Economy Efficiency in China.

This paper uses panel OLS, IV, and system GMM methods to empirically study the effects of manufacturing and producer service corporate co-agglomeration on green economy efficiency (GEE) in China. Chinese panel data from 2000 to 2019 are collected to assess the GEE and co-agglomeration degrees. The regression results show that there is an "inverted U-shaped" relationship between co-agglomeration and GEE. However, regional heterogeneity is found in the effects of corporate co-agglomeration on GEE. The mediating analysis indicates that corporate co-agglomeration could increase GEE through business entrepreneurship and innovation entrepreneurship. Variables such as transportation infrastructure, human capital, foreign direct investment, and environmental regulations are also found to have an elevating effect on GEE, whereas local fiscal expenditure on environmental protection has little effect. The findings in this paper indicate that entrepreneurship plays an important role in the process of co-agglomeration impacting GEE which differs in different regions and thus provide references for corporate and regional sustainable development.

Interleukin-6 upregulates SOX18 expression in osteosarcoma.

AIM: SOX18 is a potential oncogene in osteosarcoma via controlling osteosarcoma cell proliferation and metastasis. Interleukin-6 (IL-6), a major activator of Janus kinase 2 (JAK2)/signal transducers and activators of transcription 3 (STAT3) signaling, plays an important role in the growth of carcinoma cells. The present study aims to investigate the correlation between IL-6 and SOX18 in osteosarcoma. MATERIALS AND METHODS: Protein expression and mRNA expression were determined by Western blot and real-time polymerase chain reaction (PCR) analysis, respectively. Cell proliferation and apoptosis were identified by Cell Counting Kit-8 assay and flow cytometry analysis, respectively. RESULTS: We found that SOX18, IL-6 and p-STAT3 were elevated in osteosarcoma compared with bone cyst tissues. A positive correlation between the mRNA levels of IL-6 and SOX18 was observed in osteosarcoma tissues. IL-6 stimulation dose dependently induced the mRNA and protein levels of SOX18 in U-2OS and MG63 cells. Furthermore, IL-6 significantly rescued the inhibitory and induction effects of SOX18 knockdown on osteosarcoma cell proliferation and apoptosis, respectively. The changes in cell proliferation (PCNA) and apoptosis-related proteins (Bcl-2, Bax and Cleaved-Caspase 3) were in line with the results of cell proliferation and apoptosis assays. CONCLUSION: Our data suggest that IL-6 is a possible upstream regulator for SOX18 in osteosarcoma.

Inhibition of Adhesion of Enteropathogenic Escherichia coli to HEp-2 Cells by Binding of a Novel Peptide to EspB Protein.

Enteropathogenic Escherichia coli (EPEC) is a major cause of infantile diarrhea in developing countries. The translocator EspB is a key virulence factor in the process of the attaching and effacing effect of EPEC and plays a critical role in the pathogenesis of the bacteria. In this study, we aimed to select the peptides binding to EspB protein by phage display library and further investigate whether these peptides can decrease the extent of invasion and virulence of EPEC on host cells by targeting to EspB protein. The expression and purification of EspB protein from E. coli was demonstrated by Western blotting. The Ph.D. 12-mer peptide phage display library was used to screen the candidate peptides binding specifically to EspB protein. Furthermore, the affinity of these candidate peptides bound to EspB was identified by enzyme-linked immunosorbent assay (ELISA). Moreover, we investigated whether these screened peptides could decrease the adherence ratio of EPEC to HEp-2 cells with increasing concentration. Successful purification of EspB protein from pET21b-EspB-transformed E. coli was identified by Western blotting. Then, the candidate peptides including phages 6, 7, 8, and 12 were screened by the Ph.D. 12-mer peptide phage display library and ELISA test demonstrated that their affinity binding to EspB protein was high compared with the control. Functional analysis indicated that synthetic peptide-6 (YFPYSHTSPRQP) significantly decreased the adherence ratio of EPEC to HEp-2 cells with increasing concentration (P < 0.01). Peptide-6 (100 µg/mL) could lead to a 40 % decrease in the adherence ratio of EPEC to HEp-2 cells compared with control (P < 0.01). However, the other three peptides at different concentrations showed only a slight ability to block the adherence of EPEC to host cells. Our data provided a potential strategy to inhibit the adhesion of EPEC to epithelial cells by a candidate peptide targeted toward EspB protein.

Electrospinning of PELA/PPY Fibrous Conduits: Promoting Peripheral Nerve Regeneration in Rats by Self-Originated Electrical Stimulation.

Peripheral nerve injuries represent a great challenge for surgeons. The conductive neural scaffold has experienced increasing interest because of its good biocompatibility and similar electrical properties as compared to those of a normal nerve. Herein, nerve conduits made from poly(d,l-lactide)-co-poly(ethylene glycol) and polypyrrole (20%, 30%, and 50%) (PELA-PPY) were prepared by electrospinning, and used in regeneration of peripheral nerve defects. The results of an in vitro experiment indicated a high biocompatibility for the as-prepared materials, supporting the attachment and proliferation of a rat pheochromocytoma PC-12 cell. Furthermore, the PELA-PPY nerve conduit implanted in the sciatic nerve defects (10 mm) of the Spraguee-Dawley rats for 12 weeks showed similar results with the autograft, while it demonstrated a better outcome than the PELA nerve conduit in electrophysiological examination, sciatic function index, total amount of regenerated myelinated nerve fibers, axon diameter, myelin thickness, and several immunohistochemistry indices (S-100, laminin, neurofilament, bromodeoxyuridine, and glial fibrillary acidic portein). We supposed that the bioactivity is mainly generated by the PPY in composite nanofibers which could transmit self-originated electrical stimulation between cells. Due to the facile preparation and excellent in vivo performance, the PPY-PELA nerve conduit is promising for use as a bioengineered biomaterial for peripheral nerve regeneration.

Removal of nutrients from septic tank effluent with baffle subsurface-flow constructed wetlands.

Three new baffle flow constructed wetlands (CWs), namely the baffle horizontal flow CW (Z1), baffle vertical flow CW (Z2) and baffle hybrid flow CW (Z3), along with one traditional horizontal subsurface flow CW (Z4) were designed to test the removal efficiency of nitrogen (N) and phosphorus (P) from the septic tank effluent under varying hydraulic retention times (HRTs). Results showed that the optimal HRT was two days for maximal removal of N and P from the septic tank effluent among the four CWs. At this HRT, the Z1, Z2, Z3 and Z4 CWs removed, respectively, 49.93, 58.50, 46.01 and 44.44% of TN as well as 87.82, 93.23, 95.97 and 91.30% of TP. Our study further revealed that the Z3 CW was the best design for overall removal of N and P from the septic tank effluent due to its hybrid flow directions with better oxygen supply inside the CW system.

Recurrent linezolid-resistant Enterococcus faecalis infection in a patient with pneumonia.

OBJECTIVE: It has been reported that LZD-resistant Enterococcus in the gastrointestinal tract of mice colonizes persistently and shows variable minimum inhibitor concentration (MIC) values. However, the colonization characteristics of Enterococcus with LZD resistance in patients remain elusive. Here, we report the case of a patient with recurrent pneumonia due to infection with LZD-resistant Enterococcus faecalis strains. The colonization characteristics of the strains isolated from this patient were analyzed. METHODS: Ten E. faecalis strains were isolated from tracheal secretions obtained from the patient during five recurrences of pneumonia over the course of 10 months. Clonal relationships were determined by pulsed-field gel electrophoresis (PFGE) with SmaI-macrorestricted genomic DNA. The susceptibility of the isolates to LZD was determined by Etest in Mueller-Hinton agar. RESULTS: The homology of these strains was demonstrated by PFGE, suggesting that occult bacterial colonization by LZD-resistant E. faecalis is possible as late as a year after exposure to LZD. These strains showed variable MICs as determined by the Etest. LZD-resistant isolates contained single or double nucleotide mutations in domain V of 23S rRNA as confirmed by PCR and sequencing. The sensitivity of the strains to vancomycin was demonstrated by broth macrodilution, and vancomycin was an effective clinical treatment on each occasion. CONCLUSIONS: Our results indicate that LZD-resistant E. faecalis strains may colonize persistently in vivo, leading to recurrent infection.

Directed shift of vaginal microbiota induced by vaginal application of sucrose gel in rhesus macaques.

OBJECTIVES: Sucrose gel was used to treat bacterial vaginosis in a phase III clinical trial. However, the changes of vaginal flora after treatment were only examined by Nugent score in that clinical trial, While the vaginal microbiota of rhesus macaques is characterized by anaerobic, Gram-negative bacteria, few lactobacilli, and pH levels above 4.6, similar to the microbiota of patients with bacterial vaginosis. This study is aimed to investigate the change of the vaginal microbiota of rehsus macaques after topical use of sucrose gel to reveal more precisely the bacterial population shift after the topical application of sucrose gel. METHODS: Sixteen rhesus macaques were treated with 0.5 g sucrose gel vaginally and three with 0.5 g of placebo gel. Vaginal swabs were collected daily following treatment. Vaginal pH levels and Nugent scores were recorded. The composition of the vaginal micotbiota was tested by V3∼V4 16S rDNA metagenomic sequencing. Dynamic changes in the Lactobacillus genus were analyzed by qPCR. RESULTS: The vaginal microbiota of rhesus macaques are dominated by anaerobic Gram-negative bacteria, with few lactobacilli and high pH levels above 4.6. After five days' treatment with topical sucrose gel, the component percentage of Lactobacillus in vaginal microbiota increased from 1.31% to 81.59%, while the component percentage of Porphyromonas decreased from 18.60% to 0.43%, Sneathia decreased from 15.09% to 0.89%, Mobiluncus decreased from 8.23% to 0.12%, etc.. The average vaginal pH values of 16 rhesus macaques of the sucrose gel group decreased from 5.4 to 3.89. There were no significant changes in microbiota and vaginal pH observed in the placebo group. CONCLUSIONS: Rhesus macaques can be used as animal models of bacterial vaginosis to develop drugs and test treatment efficacy. Furthermore, the topical application of sucrose gel induced the shifting of vaginal flora of rhesus macaques from a BV kind of flora to a lactobacilli-dominating flora.

Complete genome sequencing and comparative analysis of the linezolid-resistant Enterococcus faecalis strain DENG1.

Genome level analysis of bacterial strains provides information on genetic composition and resistance mechanisms to clinically relevant antibiotics. To date, whole genome characterization of linezolid-resistant Enterococcus faecalis isolated in the clinic is lacking. In this study, we report the entire genome sequence, genomic characteristics and virulence factors of a pathogenic E. faecalis strain, DENG1. Our results showed considerable differences in genomic characteristics and virulence factors compared with other E. faecalis strains (V583 and OG1RF). The genome of this LZD-resistant E. faecalis strain can be used as a reference to study the mechanism of LZD resistance and the phylogenetic relationship of E. faecalis strains worldwide.

Evaluation of nutrient removal efficiency and microbial enzyme activity in a baffled subsurface-flow constructed wetland system.

In this study, the enzyme activities and their relationships to domestic wastewater purification are investigated in four different types of subsurface-flow constructed wetlands (CWs), namely the traditional horizontal subsurface-flow, horizontal baffled subsurface-flow, vertical baffled subsurface-flow, and composite baffled subsurface-flow CWs. Results showed that the urease activity in the composite baffled subsurface-flow CW was significantly higher than in the other three CWs, while the phosphatase activity in the vertical baffled subsurface-flow CW were higher than in the other three CWs. There were significant and very significant correlations between the activities of urease and the removal rates of TN and NH4(+)-N for the horizontal baffled flow, horizontal subsurface flow, and composite baffled subsurface flow CWs. This study suggests that the activity of urease in the root zones of those three CWs is an important indicator for N purification from wastewaters.

Preclinical evaluation of herpes simplex virus armed with granulocyte-macrophage colony-stimulating factor in pancreatic carcinoma.

AIM: To investigate the therapeutic efficacy and mechanisms of action of oncolytic-herpes-simplex-virus encoding granulocyte-macrophage colony-stimulating factor (HSV(GM-CSF)) in pancreatic carcinoma. METHODS: Tumor blocks were homogenized in a sterile grinder in saline. The homogenate was injected into the right armpit of each mouse. After vaccination, the mice were randomly assigned into four groups: a control group, a high dose HSV(GM-CSF) group [1 × 107 plaque forming units (pfu)/tumor], a medium dose HSV(GM-CSF) group (5 × 106 pfu/tumor) and a low dose HSV(GM-CSF) group (5 × 105 pfu/tumor). After initiation of drug administration, body weights and tumor diameters were measured every 3 d. Fifteen days later, after decapitation of the animal by cervical dislocation, each tumor was isolated, weighed and stored in 10% formaldehyde solution. The drug effectiveness was evaluated according to the weight, volume and relative volume change of each tumor. Furthermore, GM-CSF protein levels in serum were assayed by enzyme-linked immunosorbent assays at 1, 2, 3 and 4 d after injection of HSV(GM-CSF). RESULTS: Injection of the recombinant mouse HSV encoding GM-CSF resulted in a significant reduction in tumor growth compared to the control group, and dose-dependent effects were observed: the relative tumor proliferation rates of the low dose, medium dose and high dose groups on 15 d after injection were 45.5%, 55.2% and 65.5%, respectively. The inhibition rates of the tumor weights of the low, middle, and high dose groups were 41.4%, 46.7% and 50.5%, respectively. Furthermore, the production of GM-CSF was significantly increased in the mice infected with HSV(GM-CSF). The increase in the GM-CSF level was more pronounced in the high dose group compared to the other two dose groups. CONCLUSION: Our study provides the first evidence that HSV(GM-CSF) could inhibit the growth of pancreatic cancer. The enhanced GM-CSF expression might be responsible for the phenomenon.

The influence of the blood handling process on the measurement of circulating TGF-ß1.

In order to evaluate the impact of blood sample handling processes on circulating TGF-ß1 levels, blood specimens were obtained from 13 healthy volunteers using different handling processes (kept at room temperature (RT) or on ice before centrifugation, using different centrifugal forces). TGF-ß1 levels were measured using an enzyme-linked immunosorbent assay. A paired-T test was used for statistical analysis. The TGF-ß1 level in on-ice serum was significantly lower than that in room-temperature serum (P<0.001), and both were significantly higher than that found in on-ice plasma (P<0.001). Compared with on-ice plasma samples, the longer the samples were kept at RT, the higher the levels of TGF-ß1 in plasma (P=0.268, 0.040, and 0.0015 for 5 min, 30 min, and 60 min in RT, respectively). Compared with plasma centrifuged at 2,500×g for 30 min, the TGF-ß1 levels were much lower than those found in plasma centrifuged at 1,200×g for 10 min (P=0.003); and a double centrifugation before TGF-ß1 detection, significantly decreased the level (P<0.001). It is suggested that the optimal sampling conditions for the detection of TGF-ß1 should be plasma prepared on ice and spun down at a higher centrifugal force.

Changes of circulating transforming growth factor-beta1 level during radiation therapy are correlated with the prognosis of locally advanced non-small cell lung cancer.

INTRODUCTION: We hypothesized that plasma transforming growth factor-beta1 (TGF-beta1) level and its dynamic change are correlated with the prognosis of locally advanced non-small cell lung cancer (NSCLC) treated with radiation therapy (RT). METHODS: Patients with stage IIIA or IIIB NSCLC treated with RT with or without chemotherapy were eligible for this study. Platelet poor plasma was collected from each patient within 1 week before RT (pre-RT) and at the 4th week during RT (during-RT). TGF-beta1 level was measured with enzyme-linked immunosorbent assay. The primary end point was overall survival (OS) and the secondary end point was progression-free survival (PFS). Kaplan-Meier and Cox regression were used for risk factor evaluation. RESULTS: A total of 65 patients were eligible for the study. The median OS and PFS were 17.7 and 13.7 months, respectively. In univariate analysis, performance status, weight loss, radiation dose, and TGF-beta1 ratio (during-RT/pre-RT TGF-beta1 level) were all significantly correlated with OS. In the multivariate analysis, performance status, radiation dose, and TGF-beta1 ratio were still significantly correlated with OS. The median OS was 30.7 months for patients with TGF-beta1 ratio

Elevation of plasma TGF-beta1 during radiation therapy predicts radiation-induced lung toxicity in patients with non-small-cell lung cancer: a combined analysis from Beijing and Michigan.

PURPOSE: To test whether radiation-induced elevations of transforming growth factor-beta1 (TGF-beta1) during radiation therapy (RT) correlate with radiation-induced lung toxicity (RILT) in patients with non-small-cell lung cancer (NSCLC) and to evaluate the ability of mean lung dose (MLD) to improve the predictive power. METHODS AND MATERIALS: Eligible patients included those with Stage I-III NSCLC treated with RT with or without chemotherapy. Platelet-poor plasma was obtained pre-RT and at 4-5 weeks (40-50 Gy) during RT. TGF-beta1 was measured using an enzyme-linked immunosorbent assay. The primary endpoint was > or = Grade 2 RILT. Mann-Whitney U test, logistic regression, and chi-square were used for statistical analysis. RESULTS: A total of 165 patients were enrolled in this study. The median radiation dose was 60 Gy, and the median MLD was 15.3 Gy. Twenty-nine patients (17.6%) experienced RILT. The incidence of RILT was 46.2% in patients with a TGF-beta1 ratio > 1 vs. 7.9% in patients with a TGF-beta1 ratio < or = 1 (p < 0.001), and it was 42.9% if MLD > 20 Gy vs. 17.4% if MLD < or = 20 Gy (p = 0.024). The incidence was 4.3% in patients with a TGF-beta1 ratio < or = 1 and MLD < or = 20 Gy, 47.4% in those with a TGF-beta1 ratio >1 or MLD > 20 Gy, and 66.7% in those with a TGF-beta1 ratio >1 and MLD > 20 Gy (p < 0.001). CONCLUSIONS: Radiation-induced elevation of plasma TGF-beta1 level during RT is predictive of RILT. The combination of TGF- beta1 and MLD may help stratify the patients for their risk of RILT.

Identification of differential gene expression profiles of radioresistant lung cancer cell line established by fractionated ionizing radiation in vitro.

BACKGROUND: Radiotherapy plays a critical role in the management of non-small cell lung cancer (NSCLC). This study was conducted to identify gene expression profiles of acquired radioresistant NSCLC cell line established by fractionated ionizing radiation (FIR) by cDNA microarray. METHODS: The human lung adenocarcinoma cell line Anip973 was treated with high energy X-ray to receive 60 Gy in 4 Gy fractions. The radiosensitivity of Anip973R and its parental line were measured by clonogenic assay. Gene expression profiles of Anip973R and its parental line were analyzed using cDNA microarray consisting of 21 522 human genes. Identified partly different expressive genes were validated by quantitative reverse transcription-polymerase chain reaction (Q-RT-PCR). RESULTS: Fifty-nine upregulated and 43 downregulated genes were identified to radio-resistant Anip973R. Up-regulated genes were associated with DNA damage repair (DDB2), extracellular matrix (LOX), cell adhesion (CDH2), and apoptosis (CRYAB). Down-regulated genes were associated with angiogenesis (GBP-1), immune response (CD83), and calcium signaling pathway (TNNC1). Subsequent validation of selected eleven genes (CD24, DDB2, IGFBP3, LOX, CDH2, CRYAB, PROCR, ANXA1 DCN, GBP-1 and CD83) by Q-RT-PCR was consistent with microarray analysis. CONCLUSIONS: Fractionated ionizing radiation can lead to the development of radiation resistance. Altered gene profiles of radioresistant cell line may provide new insights into mechanisms underlying clinical radioresistance for NSCLC.

[Preliminary study of the association between human thrombospondin and gastric cancer].

OBJECTIVE: To study the possible role of human thrombospondin (hPWTSR) in gastric cancer and explore its potential to serve as the target for gastric cancer diagnosis and intervention. METHODS: Using pLexA-hPWTSR as the bait, a premade pB42AD-based fetal brain cDNA library was constructed to identify the interacting proteins. The expression pattern of hPWTSR in gastric cancer tissues and a gastric cancer cell line was observed to investigate the correlation between hPWTSR expression and the biological behaviors of the tumor. The possibility of hPWTSR as a potential gastric cancer marker was evaluated. RESULTS: Fifty-seven independent clones were isolated from 107 clones screened. Sequence analysis indicated that the 57 positive clones represented the products of 12 genes. A RT-PCR-based expression pattern revealed that the expression of hPWTSR in gastric cancer tissues and a gastric cancer cell line was lower than that in the corresponding normal tissues, but no mutations were identified by the subsequent sequence analysis. CONCLUSIONS: hPWTSR interacts with adhesion-related proteins and tumor-related genes, and its expression is lowered in gastric cancer tissues and gastric cancer cell line. hPWTSR might play a role in gastric cancer development, especially in metastasis and might be used as a potential gastric cancer marker. The exact functions of hPWTSR and its potential clinical value still await further study.

[Multi-center phase II clinical trial of humanized anti-epidermal factor receptor monoclonal antibody h-R3 combined with radiotherapy for locoregionally advanced nasopharyngeal carcinoma].

OBJECTIVE: To evaluate the efficacy and safty of the humanized anti-epidermal factor receptor monoclonal antibody h-R3 in combination with radiotherapy for locoregionally advanced nasopharyngeal carcinoma. METHODS: Totally, 137 patients from 7 medical center around China were randomly divided into combined therapy group or control group. There was no difference in Karnofsky performance score between two groups. All patients in both groups received radical conventionally fractionated radiotherapy to the total dose of D(T) 70-76 Gy. For the combined therapy group, h-R3 was added at a dose of 100 mg i.v. weekly for 8 weeks started at the beginning of radiotherapy. RESULTS: Of the 137 eligilbe patients, 70 were in the combined therapy group treated by h-R3 plus radiotherapy and 67 in the control group by radiotherapy alone. The intent-to-treat (ITT) population consisted of 130 patients, while the per-protocol (PP) population was composed of 126 patients. The efficacy was assessed respectively at three point of time: the end of treatment, the 5th- and 17th-week after treatment. The complete response (CR) of the combined therapy group was significantly higher than that of the control group in both ITT and PP (ITT: 65.63%, 87.50%, 90.63% versus 27.27%, 42.42%, 51.52%; PP: 67.21%, 90.16%, 93.44% versus 27.69%, 43.08%, 52.31%; P < 0.05, respectively). The most common h-R3-related adverse reactions were fever (4.3%), hypotension (2.9%), nausea (1.4%), dizziness (2.9%) and rash (1.4%), which could be reversible if treated properly. Radiotherapy combined with 100 mg h-R3 i. v. weekly was tolerable and did not aggravate the side effects of radiation. The quality of life in the combined therapy group was comparable to that in the control group. CONCLUSION: This phase 1 multicenter clinical trial shows that h-R3 in combination with radiotherapy is effective and well-tolerated for the treatment of locoregionally advanced nasopharyngeal carcinoma.

Association between plasma angiotensin-converting enzyme level and radiation pneumonitis.

Angiotensin-converting enzyme (ACE) plays an important role in pulmonary fibrosis and may be involved in the development of radiation-induced lung damage. The objective of this study was to evaluate the predictive value of plasma ACE in radiation pneumonitis (RP). Patients with stage I-III lung cancer were treated with radiotherapy with or without chemotherapy. ACE levels were measured using enzyme-linked immunosorbent assay before radiotherapy (pre-RT) and when a median dose of 45 Gy (Range: 40-48 Gy) was reached (during-RT). The primary end point was > or = grade 2 RP. Statistic significances were evaluated with independent T-test and chi-square. Thirty-nine patients were enrolled in this study, among which 33.3% experienced > or = grade 2 RP. ACE levels, either pre-RT or during-RT, were significantly lower in the RP group than in the non-RP group (P=0.02 and 0.03, respectively). Nine out of the 19 patients (47.4%) with pre-RT ACE levels < or = 462 ng/mL experienced RP, versus 3 of 19 (15.8%) patients with ACE levels > 462 ng/mL (P=0.04). This study suggested that plasma ACE as a predictive factor for radiation pneumonitis deserves further study.

[Radiosensitization of paclitaxel combined with radiation on nasopharygneal carcinoma cells (CNE-I) in vitro].

OBJECTIVE: To evaluate the radiosensitization of paclitaxel combined with radiation on nasopharygneal carcinoma cells( CNE-I) in vitro. METHODS: Human CNE-I cells were used for this study. Clonogenic assay was used to determine the drug dose of IC10, IC50 and IC90 for CNE-I Cells. The cells treated with different concentration of paclitaxel for 24 hours before or after radiation (dose ranged from 0 - 10 Gy ) were used to evaluate the radiosensitizing effect of paclitaxel combined with radiation. DNA flow cytometry was performed to define the cell cycle characteristics of cell populations treated for 0, 2, 6, 12, 18, 24 h with 0.1 nmol/L, 0.5 nmol/L, 1.0 nmol/L, 2.5 nmol/L paclitaxel, respectively. RESULTS: The dose of IC10, IC50 and IC90 for paclitaxel in CNE-I cells was 0.05 nmol/L, 1.0 nmol/L and 2.5 nmol/L, respectively. Paclitaxel treatment at concentration of 0.05 nmol/L and 1.0 nmol/L for 24 hours combined with X-ray irradiation before or after radiation showed radiosensitivity-enhansing effects in CNE-I cells. G2/M block was present when the drug concentrations were 2.5 nmol/L and 10.0 nmol/L, and it peaked at 18 hours. CONCLUSION: With an optimal paclitaxel/radiation combination, paclitaxel may exert a radiosensitizing effect on CNE-I cells. The effect might be related to the G2/M block caused by paclitaxel.

[Correlation of initial DNA damage detected by alkaline comet assay and clinical endpoints in lung cancer patients].

BACKGROUND: Cells derived from lung cancer are biological heterogeneous and have different intrinsic radiosensitivity, it is a key question for us to investigate radiosensitive parameters for an individualized radiotherapy plan. The comet assay is a sensitive and facilitated method to detect single-cell DNA damage and repair, and the results from it have been proven to be so highly coincident with those from clonogenic assay by cell-line investigations that it has been considered as a promising method in predicting radiosensitivity. The study is designed to evaluate preliminarily the correlation between initial DNA damage detected by alkaline comet assay and the clinical endpoints. METHODS: Biopsy samples from 31 lung cancer patients by fibrous bronchial endoscopy were detected by alkaline comet assay from April, 2002 to November, 2002. The adjusted tail moment (R TM) was measured and thoracic local-region lesions were measured by computer tomography scan. Response rate (RR) and time to progression (TTP) for the local-region lesions were as clinical endpoints. SPSS 10.0 software was used to compare median R TM of different RR and TTP groups by Mann-Whitney U and Kruskal-Wallis H rank test, the correlations between R TM with RR and TTP were estimated by Spearman's rank test. RESULTS: There were no statistic differences of median R TM among different pathological types with a median R TM of 0.98, 1.27 and 1.05 in squamous cell carcinoma group, adenocarcinoma group and small cell lung cancer group, respectively (Chi-square=0.347, P=0.84). Through a median follow-up of 10 months, a median R TM of 1.08 and 1.21 for squamous cell carcinoma group and small cell lung cancer group in RR≥50% group was greater than 0.88 and 0.91 in RR < 50% group; median R TM in TTP > 9-monthgroups stratified according to pathological type was greater than that in TTP≤9-month groups (1.26, 1.38 and 1.39 versus 0.71, 0.48 and 1.03 for squamous cell carcinoma group, adenocarcinoma group and small cell lung cancer group respectively), but the differences of R TM classified by RR or TTP were not statistically significant (U=63.5, P=0.58; U=71, P=0.057); the Spearman's coefficients of R TM with RR and TTP were -0.105 (P=0.57) and 0.38 (P=0.035). The coefficients of R TM with TTP was 0.47 for non-small cell lung cancer indicating a modest correlation (P=0.048) and 0.043 for small cell lung cancer (P=0.89). CONCLUSIONS: Although the results are confounded due to sampling and the greater background tail moments, Spearman's coefficient of R TM with TTP for non-small cell lung cancer indicates a modest positive correlation. The comet assay might be a promising method in predicting intrinsic radiosensitivity of lung cancer cells and techniques for sampling and assaying need to be further improved.