Comparative analysis of two-hour creatinine clearance and the C-G formula for renal function assessment in critically ill patients.

Objective and rationale: To investigate if the 2-h creatinine clearance (Ccr2) provides a more precise and timely assessment of renal function in critically ill patients compared to the Cockcroft-Gault formula (CrC-G). Materials and methods: This cohort study incorporated 74 patients who were hospitalized for more than 48 h in the Intensive Care Unit over 6 months. A 24-h urine collection protocol was observed, and concurrently, 316 2-h urine specimens were obtained. Then calculated and analyzed the correlation and consistency between Ccr2, CrC-G, and 24-h creatinine clearance (Ccr24) values. The rates of change in Ccr2(ΔCcr2) and CrC-G(ΔCrC-G) were compared over two consecutive samples. Results: The R-values of Ccr2 and Ccr24 in the early, middle and late 24 h were 0.640, 0.886 and 0.854 (P < 0.001), with biases of -2.1, 1.7, and 6.3 ml/min/1.73 m2, respectively. Meanwhile, the R-values for CrC-G and Ccr24 at these time points were 0.618, 0.822, and 0.828(P < 0.001), with biases of -14.0, -5.2, and -1.8 ml/min/1.73 m2, respectively. For patients with Ccr24≥60 ml/min/1.73 m2, the R-value of Ccr2 and Ccr24 during the middle 2 h was 0.852(P < 0.001), while the R-values for CrC-G and Ccr24 were 0.763(P < 0.001), with biases of -2.3 ml/min/1.73 m2 and -14.2 ml/min/1.73 m2 respectively. For the group with Ccr24 ≥ 120 ml/min/1.73 m2 (n = 72), both Ccr2 and Ccr24 displayed a statistically significant elevation compared to CrC-G (P < 0.001), yet no significant difference was observed between Ccr2 and Ccr24 (P = 0.289). Out of 50 patients, 46(92 %) experienced a ΔCcr2≥20 % at least once, compared to 20(40 %) with a ΔCrC-G≥20 %(P < 0.001). 25(50 %) with a ΔCcr2≥50 %, compared to 3(6 %) with a ΔCrC-G≥50 %(P < 0.001). Conclusion: Ccr2 demonstrates a more accurate and more timely indicator of renal function in critically ill patients than CrC-G.

Highly sensitive fluorescent detection of EDIL3 overexpressed exosomes for the diagnosis of triple-negative breast cancer.

EDIL3 is a strong and highly accurate diagnostic marker for breast cancer, meanwhile, EDIL3 overexpressed exosomes are novel biomarkers for the early diagnosis of triple-negative breast cancer (TNBC). Here, we proposed a fluorescent detection method for EDIL3 overexpressed exosomes, which is simple and sensitive. Basically, we utilized a magnetic nanospheres (MNS) based liquid sandwich immunoassay strategy. MNS were modified with CD63 aptamers, which can immunologically bound to the CD63 protein on the surface of exosomes. Alexa Fluor 647 labeled anti-EDIL3 antibodies (Anti-EDIL3/AF647) were used as the fluorescent probes to recognize the EDIL3 on exosomes derived from a TNBC cell line (MDA-MB-231). With the target TNBC exosomes present, sandwich structures containing MNS, exosomes and fluorescent probes were formed. After magnetic purification, optical super resolution imaging of the products was conducted to check the specificity of the assay. In addition, fluorescence signals of the products were detected to quantitatively analyze the EDIL3 overexpressed exosomes. The linear range was found to be 7.78 × 101to 7.78× 106particlesµl-1. The detection limit was approximately 10 particlesµl-1. The feasibility of the method for the detection of exosomes in complex biological samples was also demonstrated. Such a simple and sensitive detection method for EDIL3 overexpressed exosomes holds a great potential in clinical diagnosis of TNBC.

Glutathione peroxidase 4-dependent glutathione high-consumption drives acquired platinum chemoresistance in lung cancer-derived brain metastasis.

BACKGROUND: Platinum-based chemotherapy is effective in inducing shrinkage of primary lung cancer lesions; however, it shows finite therapeutic efficacy in patients suffering from brain metastasis (BM). The intrinsic changes of BM cells, which contribute to the poor results remain unknown. METHODS: Platinum drug-sensitivity was assessed by utilizing a preclinical BM model of PC9 lung adenocarcinoma cells in vitro and in vivo. High consumption of glutathione (GSH) and two associated upregulated proteins (GPX4 and GSTM1) in BM were identified by integrated metabolomics and proteomics in cell lines and verified by clinical serum sample. Gain-of-function and rescue experiments were implemented to reveal the impact and mechanism of GPX4 and GSTM1 on the chemosensitivity in BM. The interaction between GPX4 and GSTM1 was examined by immunoblotting and immunoprecipitation. The mechanism of upregulation of GPX4 was further uncovered by luciferase reporter assay, immunoprecipitation, and electrophoretic mobility shift assay. RESULTS: The derivative brain metastatic subpopulations (PC9-BrMs) of parental cells PC9 developed obvious resistance to platinum. Radically altered profiles of BM metabolism and protein expression compared with primary lung cancer cells were described and GPX4 and GSTM1 were identified as being responsible for the high consumption of GSH, leading to decreased chemosensitivity by negatively regulating ferroptosis. Besides, GSTM1 was found regulated by GPX4, which was transcriptionally activated by the Wnt/NR2F2 signaling axis in BM. CONCLUSIONS: Collectively, our findings demonstrated that Wnt/NR2F2/GPX4 promoted acquired chemoresistance by suppressing ferroptosis with high consumption of GSH. GPX4 inhibitor was found to augment the anticancer effect of platinum drugs in lung cancer BM, providing novel strategies for lung cancer patients with BM.

Differential diagnosis between small breast phyllodes tumors and fibroadenomas using artificial intelligence and ultrasound data.

BACKGROUND: It is challenging to differentiate between phyllodes tumors (PTs) and fibroadenomas (FAs). Artificial intelligence (AI) can provide quantitative information regarding the morphology and textural features of lesions. This study attempted to use AI to evaluate the ultrasonic images of PTs and FAs and to explore the diagnostic performance of AI features in the differential diagnosis of PTs and FAs. METHODS: A total of 40 PTs and 290 FAs <5 cm in maximum diameter found in female patients were retrospectively analyzed. All tumors were segmented by doctors, and the features of the lesions were collated, including circularity, height-to-width ratio, margin spicules, margin coarseness (MC), margin indistinctness, margin lobulation (ML), internal calcification, angle between the long axis of the lesion and skin, energy, grey entropy, and grey mean. The differences between PTs and FAs were analyzed, and the diagnostic performance of AI features in the differential diagnosis of PTs and FAs was evaluated. RESULTS: Statistically significant differences (P<0.05) were found in the height-to-width ratio, ML, energy, and grey entropy between the PTs and FAs. Receiver operating characteristic (ROC) curve analysis of single features showed that the area under the curve [(AUC) 0.759] of grey entropy was the largest among the four features with statistically significant differences, and the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 0.925, 0.459, 0.978, and 0.190, respectively. When considering the combinations of the features, the combination of height-to-width ratio, margin indistinctness, ML, energy, grey entropy, and internal calcification was the most optimal of the combinations of features with an AUC of 0.868, and a sensitivity, specificity, PPV, and NPV of 0.734, 0.900, 0.982, and 0.316, respectively. CONCLUSIONS: Quantitative analysis of AI can identify subtle differences in the morphology and textural features between small PTs and FAs. Comprehensive consideration of multiple features is important for the differential diagnosis of PTs and FAs.

Cancer-associated fibroblast-derived SDF-1 induces epithelial-mesenchymal transition of lung adenocarcinoma via CXCR4/ß-catenin/PPARδ signalling.

Cancer-associated fibroblasts (CAFs) contribute to tumour epithelial-mesenchymal transition (EMT) via interaction with cancer cells. However, the molecular mechanisms underlying tumour-promoting EMT of CAFs in lung adenocarcinoma (ADC) remain unclear. Here, we observed that CAFs isolated from lung ADC promoted EMT via production of stromal cell-derived factor-1 (SDF-1) in conditioned medium (CM). CAF-derived SDF-1 enhanced invasiveness and EMT by upregulating CXCR4, ß-catenin, and PPARδ, while downregulating these proteins reversed the effect. Furthermore, RNAi-mediated CXCR4 knockdown suppressed ß-catenin and PPARδ expression, while ß-catenin inhibition effectively downregulated PPARδ without affecting CXCR4; however, treatment with a PPARδ inhibitor did not inhibit CXCR4 or ß-catenin expression. Additionally, pairwise analysis revealed that high expression of CXCR4, ß-catenin, and PPARδ correlated positively with 75 human lung adenocarcinoma tissues, which was predictive of poor prognosis. Thus, targeting the CAF-derived, SDF-1-mediated CXCR4 ß-catenin/ PPARδ cascade may serve as an effective targeted approach for lung cancer treatment.

Evaluation of the safety and efficacy of using human menstrual blood-derived mesenchymal stromal cells in treating severe and critically ill COVID-19 patients: An exploratory clinical trial.

The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was identified in December 2019 and has subsequently spread worldwide. Currently, there is no effective method to cure COVID-19. Mesenchymal stromal cells (MSCs) may be able to effectively treat COVID-19, especially for severe and critical patients. Menstrual blood-derived MSCs have recently received much attention due to their superior proliferation ability and their lack of ethical problems. Forty-four patients were enrolled from January to April 2020 in a multicenter, open-label, nonrandomized, parallel-controlled exploratory trial. Twenty-six patients received allogeneic, menstrual blood-derived MSC therapy, and concomitant medications (experimental group), and 18 patients received only concomitant medications (control group). The experimental group was treated with three infusions totaling 9 × 107 MSCs, one infusion every other day. Primary and secondary endpoints related to safety and efficacy were assessed at various time points during the 1-month period following MSC infusion. Safety was measured using the frequency of treatment-related adverse events (AEs). Patients in the MSC group showed significantly lower mortality (7.69% died in the experimental group vs 33.33% in the control group; P = .048). There was a significant improvement in dyspnea while undergoing MSC infusion on days 1, 3, and 5. Additionally, SpO2 was significantly improved following MSC infusion, and chest imaging results were improved in the experimental group in the first month after MSC infusion. The incidence of most AEs did not differ between the groups. MSC-based therapy may serve as a promising alternative method for treating severe and critical COVID-19.

Application of ultrasound artificial intelligence in the differential diagnosis between benign and malignant breast lesions of BI-RADS 4A.

BACKGROUND: The classification of Breast Imaging Reporting and Data System 4A (BI-RADS 4A) lesions is mostly based on the personal experience of doctors and lacks specific and clear classification standards. The development of artificial intelligence (AI) provides a new method for BI-RADS categorisation. We analysed the ultrasonic morphological and texture characteristics of BI-RADS 4A benign and malignant lesions using AI, and these ultrasonic characteristics of BI-RADS 4A benign and malignant lesions were compared to examine the value of AI in the differential diagnosis of BI-RADS 4A benign and malignant lesions. METHODS: A total of 206 lesions of BI-RADS 4A examined using ultrasonography were analysed retrospectively, including 174 benign lesions and 32 malignant lesions. All of the lesions were contoured manually, and the ultrasonic morphological and texture features of the lesions, such as circularity, height-to-width ratio, margin spicules, margin coarseness, margin indistinctness, margin lobulation, energy, entropy, grey mean, internal calcification and angle between the long axis of the lesion and skin, were calculated using grey level gradient co-occurrence matrix analysis. Differences between benign and malignant lesions of BI-RADS 4A were analysed. RESULTS: Significant differences in margin lobulation, entropy, internal calcification and ALS were noted between the benign group and malignant group (P = 0.013, 0.045, 0.045, and 0.002, respectively). The malignant group had more margin lobulations and lower entropy compared with the benign group, and the benign group had more internal calcifications and a greater angle between the long axis of the lesion and skin compared with the malignant group. No significant differences in circularity, height-to-width ratio, margin spicules, margin coarseness, margin indistinctness, energy, and grey mean were noted between benign and malignant lesions. CONCLUSIONS: Compared with the naked eye, AI can reveal more subtle differences between benign and malignant BI-RADS 4A lesions. These results remind us carefully observation of the margin and the internal echo is of great significance. With the help of morphological and texture information provided by AI, doctors can make a more accurate judgment on such atypical benign and malignant lesions.

GALNT6 promotes invasion and metastasis of human lung adenocarcinoma cells through O-glycosylating chaperone protein GRP78.

Lung adenocarcinoma remains a threat to human health due to its high rate of recurrence and distant metastasis. However, the molecular mechanism underlying lung adenocarcinoma metastasis remains yet incompletely understood. Here, we show that upregulated expression of polypeptide N-acetylgalactosaminyltransferase6 (GALNT6) in lung adenocarcinoma is associated with lymph node metastasis and poor prognosis. In lung adenocarcinoma cells, GALNT6 over-expression promoted epithelial-mesenchymal transition (EMT), wound healing, and invasion which could be significantly reversed by GALNT6 silencing. GALNT6 silencing also mitigated the metastasis of lung adenocarcinoma and prolonged the survival of xenograft tumor-bearing mice. Furthermore, GALNT6 directly interacted with, and O-glycosylated chaperone protein GRP78, which promoted EMT by enhancing the MEK1/2/ERK1/2 signaling in lung cancer cells. Therefore, GALNT6 is emerging as novel positive regulator for the malignancy of human lung adenocarcinoma. Targeting GALNT6-GRP78-MEK1/2/ERK1/2 may thus represent a new avenue to develop therapeutics against lung cancer metastasis.

Proteomic Reveals Reasons for Acquired Drug Resistance in Lung Cancer Derived Brain Metastasis Based on a Newly Established Multi-Organ Microfluidic Chip Model.

Anti-tumor drugs can effectively shrink the lesions of primary lung cancer; however, it has limited therapeutic effect on patients with brain metastasis (BM). A BM preclinical model based on a multi-organ microfluidic chip has been established proficiently in our previous work. In this study, the BM subpopulation (PC9-Br) derived from the parental PC9 cell line was isolated from the chip model and found to develop obvious resistance to antineoplastic drugs including chemotherapeutic agents (cisplatin, carboplatin, pemetrexed) and tyrosine kinase inhibitors (TKIs) which target epidermal growth factor receptor (EGFR); this suggested that the acquisition of drug-resistance by brain metastatic cells was attributable to the intrinsic changes in PC9-Br. Hence, we performed proteomic and revealed a greatly altered spectrum of BM protein expression compared with primary lung cancer cells. We identified the hyperactive glutathione (GSH) metabolism pathway with the overexpression of various GSH metabolism-related enzymes (GPX4, RRM2, GCLC, GPX1, GSTM4, GSTM1). Aldehyde dehydrogenases (ALDH1A1, ALDH3A1) were also found to be upregulated in BM. What's more, loss of EGFR and phosphorylated EGFR in PC9-Br gave reasons for the TKIs resistance. Collectively, our findings indicated potential mechanisms for the acquirement of drug resistance occurred in BM, providing new strategies to overcome therapeutic resistance in lung cancer BM.

Epithelial-mesenchymal transition markers screened in a cell-based model and validated in lung adenocarcinoma.

BACKGROUND: Re-capture of the differences between tumor and normal tissues observed at the patient level in cell cultures and animal models is critical for applications of these cancer-related differences. The epithelial-mesenchymal transition (EMT) process is essential for tumor migratory and invasive capabilities. Although plenty of EMT markers are revealed, molecular features during the early stages of EMT are poorly understood. METHODS: A cell-based model to induce lung cell (A549) EMT using conditioned medium of in vitro cancer activated fibroblast (WI38) was established. High-throughput sequencing methods, including RNA-seq and miRNA-seq, and advanced bioinformatics methods were used to explore the transcriptome profile transitions accompanying the progression of EMT. We validated our findings with experimental techniques including transwell and immunofluorescence assay, as well as the TCGA data. RESULTS: We have constructed an in vitro cell model to mimic the EMT in patients. We discovered that several new transcription factors were among the early genes (3 h) to respond to cancer micro-environmental cues which could play critical roles in triggering further EMT signals. The early EMT markers also included genes encoding membrane transporters and blood coagulation function. Three of the nine-examined early EMT hallmark genes, GALNT6, SPARC and HES7, were up-regulated specifically in the early stages of lung adenocarcinoma (LUAD) and confirmed by TCGA patient transcriptome data. In addition, we showed that miR-3613, a regulator of EGFR pathway genes, was constantly repressed during EMT progress and indicative of an epithelial miRNA marker. CONCLUSIONS: The CAF-stimulated EMT cell model may recapture some of the molecular changes during EMT progression in clinical patients. The identified early EMT hallmark genes GALNT6, SPARC and HES7and miR-3613 provide new markers and therapeutic targets for LUAD for the further clinical diagnosis and drug screening.

A tridecaptin-based fluorescent probe for differential staining of Gram-negative bacteria.

The traditional Gram-staining method, which was invented more than a century ago for differentiating bacteria as Gram positive or Gram negative, is still widely practiced in microbiology. However, Gram staining suffers from several problems which can affect the accuracy of the diagnosis. Here, we report a new Gram-negative-specific fluorescent probe, which is based on a narrow-spectrum antibiotic, tridecaptin A1, and allows selective staining of Gram-negative bacteria in different fixed bacterial samples. Solid-phase peptide synthesis was used to prepare the tridecaptin A1-fluorophore conjugate with a single structure. Labeling selectivity of the probe toward Gram-negative bacteria was confirmed by testing against a panel of bacterial species. By combining the use of a previously reported Gram-positive-specific fluorescent probe, we then further showed the capability of the new probe in differential labeling of a number of complex bacterial samples, which included a mouse gut microbiota cultured in vitro, as well as microbiotas collected from the human oral cavity, soil, and crude oil. High labeling selectivity and coverage were observed in most samples. This method offers a new Gram-negative-specific probe with a defined structure, which allows facile fluorescence-based differentiation of Gram-positive and Gram-negative bacteria for further microbial studies.

A microfluidic device for studying chemotaxis mechanism of bacterial cancer targeting.

Bacterial cancer targeting may become an efficacious cancer therapy, but the mechanisms underlying bacterial specificity for cancer cells need to be explored prior to adopting it as a new clinical application. To characterize the mechanism of bacterial chemotactic preference towards cancer cells, we developed a microfluidic device for in vitro study. The device consists of a cell culture chamber on both sides of a central bacteria channel, with micro-channels used as barriers between them. The device, when used as model for lung cancer, was able to provide simultaneous three-dimensional co-culture of multiple cell lines in separate culture chambers, and when used as model for bacterial chemotaxis, established constant concentration gradients of biochemical compounds in a central channel by diffusion through micro-channels. Fluorescence intensity of green fluorescence protein (GFP)-encoding bacteria was used to measure bacterial taxis behavior due to established chemotactic gradients. Using this platform, we found that Escherichia coli (E. coli) clearly illustrated the preference for lung cancer cells (NCI-H460) which was attributed to biochemical factors secreted by carcinoma cells. Furthermore, by secretome analysis and validation experiments, clusterin (CLU) was found as a key regulator for the chemotaxis of E. coli in targeting lung cancer.

Influence of microRNA­34a on proliferation, invasion and metastasis of HCT116 cells.

The aim of the present study was to investigate the role of microRNA (miR)­34a expression in the proliferation, invasion and metastasis of colon cancer and its underlying mechanisms. HCT116 cells were cultured in high­sugar Dulbecco's modified Eagle's medium (DMEM) containing 10% fetal bovine serum and 1000 U/ml penicillin­streptomycin. Following digestion and resuspension, the cells were used for transfection, expression and western blot analysis. HCT116 cells from miR­34a transfection, negative control and blank control groups were seeded into a 96­well plate at a density of 105 cells/ml, and 200 µl complete DMEM was added. The data are presented as the mean ± standard error. A one­way analysis of variance was performed to compare groups. miR­34a­HCT116 cells demonstrated significantly increased expression levels of miR­34a. The proliferation of HCT116 cells with overexpression of miR­34a was significantly inhibited to 0.49±0.11 compared with the blank control group (P<0.001). Compared with the blank control and negative control groups, the protein expression levels of B­cell lymphoma 2 (Bcl­2) were markedly reduced in the miR­34a transfected group. Furthermore, the protein expression levels of Bcl­2­associated X protein were significantly increased and those of matrix metalloproteinase (MMP)­2 and MMP­9 were markedly reduced in the miR­34a transfected group, MMP­9 to a greater extent. The present study suggested that overexpression of miR­34a may inhibit the proliferation, invasion and metastasis of HCT116 cells.

Age at menarche and risk of colorectal cancer: a meta-analysis.

BACKGROUND: Various observational studies have focused on the relationship between menarcheal age and the risk of colorectal cancer (CRC). However, the association is still controversial because of inconsistent results. Therefore, we performed a meta-analysis to assess this issue from epidemiological studies. METHODS: After a literature search in MEDLINE, EMBASE, and Web of Science for studies of menarcheal age and CRC risk published through the end of January 2013, we pooled the relative risks (RRs) from included studies using a fixed- or random-effects model and performed heterogeneity and publication bias analyses. All statistical tests were two-sided. RESULTS: Eleven case-control and 11 cohort studies were eligible for inclusion in our analysis. The random-effects pooled RR for oldest versus youngest menarcheal age was 0.95 [95% confidence intervals (CIs) = 0.85-1.06], with significant heterogeneity (Q = 61.03, P<0.001, I (2) = 65.6%). When separately analyzed, case-control (RR = 0.95, 95% CI = 0.75-1.21) and cohort studies (RR = 0.97, 95% CI = 0.90-1.04) yielded similar results. Moreover, similar results were also observed among the subgroup analyses by study quality, population, exposure assessment, anatomic cancer site, subsite of colon cancer, and several potential important confounders and risk factors. There was no evidence of publication bias and significant heterogeneity between subgroups detected by meta-regression analyses. CONCLUSIONS: Findings from this meta-analysis demonstrated that menarcheal age was not associated with the risk of CRC in humans. Further studies are warranted to stratify results by the subsite of colon cancer and menopause status in the future.

Improvement of hypoxia-ischemia-induced white matter injury in immature rat brain by ethyl pyruvate.

Ethyl pyruvate (EP) has been reported to be neuroprotective in several models of brain injury, yet its influence on periventricular leukomalacia still remains elusive. Here we investigated whether repeated administration of EP could protect against white matter injury after hypoxia-ischemia (HI) (right common carotid artery ligation and 6 % O2 for 60 min) in post-natal 3 day rat pups. EP was injected (50 mg/kg, intraperitoneally) 10 min, 1 and 24 h after HI insult. Treatment with EP significantly reduced HI-induced ventricular enlargement, loss of developing oligodendrocytes, and hypomyelination. We further demonstrated a marked inhibitory effect of EP on inflammatory responses, as indicated by the decreased number of activated microglia and astrocytes and the reduced release of proinflammatory cytokines. Moreover, EP down-regulated the expression of cleaved caspase-3 and Bax, and up-regulated Bcl-2 expression after HI exposure. In conclusion, our results demonstrated that EP was able to provide potent protection on white matter injury through blocking the cerebral inflammatory responses and modulating the apoptotic death program of oligodendrocytes, indicating a potential neuroprotective agent in neonatal brain injury.

Ethyl pyruvate protects against lipopolysaccharide-induced white matter injury in the developing rat brain.

The neuroprotective effects of ethyl pyruvate (EP) have been proved in several brain injury models, yet very little is known about its action on neonatal white matter injury. To investigate the effect of EP on white matte damage, a stereotactic intracerebral injection of lipopolysaccharide (LPS, 1mg/kg) was performed on postnatal day 5 Sprague-Dawley rat pups, and EP was administrated intraperitoneally at a dose of 40mg/kg immediately, 1h and 12h after LPS exposure. Significantly, treatment with EP reduced LPS-induced ventricle dilation, loss of O4+ and O1+ oligodendrocytes, apoptosis of oligodendrocytes, and hypomyelination. The protective effect of EP was associated with suppressed inflammatory responses, indicated by the inhibition of activation of microglia and astrocytes, as well as the decreased expression of tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1ß) in rat brains. Also, EP prevented the elevation of cleaved caspase-3 in periventricular white matter tissue after LPS insult. Taken together, these results suggest that EP confers potent protection against LPS-induced white matter injury via its anti-inflammatory and anti-apoptotic properties.

Down-regulation of GRP78 is associated with the sensitivity of chemotherapy to VP-16 in small cell lung cancer NCI-H446 cells.

BACKGROUND: Chemotherapy resistance remains a major obstacle for the treatment of small cell lung cancer (SCLC). Glucose-regulated protein 78 (GRP78), an endoplasmic reticulum chaperone, plays a critical role in chemotherapy resistance in some cancers. However, whether the suppression of the chaperone can enhance the sensitivity of chemotherapy in SCLC is still unclear. METHODS: The SCLC NCI-H446 cells were divided into three groups: BAPTA-AM-->A23187-treated group, A23187-treated group and control-group. Immunofluorescence, western blot and RT-PCR were used to assess the expression of GRP78 at both protein and mRNA levels. Cell apoptosis and the cell cycle distributions of the cells were analyzed by flow cytometry in order to evaluate the therapeutic sensitivity to VP-16. RESULTS: The expression of GRP78 at both protein and mRNA levels in the BAPTA-AM-->A23187-treated cells dramatically decreased as compared to that in both A23187-treated and control groups. After treatment by VP-16, the percentage of apoptotic cells in BAPTA-AM-->A23187-treated cells were: 33.4 +/- 1.01%, 48.2 +/- 1.77%, 53.0 +/- 1.43%, 56.5 +/- 2.13%, respectively, corresponding to the concentrations of BAPTA-AM 10, 15, 25, 40 microM, which was statistically significant high in comparison with the A23187-treated group and untreated-group (7.18 +/- 1.03% and 27.8 +/- 1.45%, respectively, p < 0.05). The results from analysis of cell cycle distribution showed that there was a significantly decreased in G1 phase and a dramatically increased in S phase for the BAPTA-AM-->A23187-treated cells as compared with the untreated cells. CONCLUSION: BAPTA-AM is a strong inhibitor of GRP78 in the NCI-H446 cell line, the down-regulation of GRP78 can significantly increase the sensitivity to VP-16. The suppression of GRP78 may offer a new surrogated therapeutic approach to the clinical management of lung cancer.

Antisense RNA-mediated suppression of Bmi-1 gene expression inhibits the proliferation of lung cancer cell line A549.

The oncogene Bmi-1 regulates cell proliferation and senescence. It is reported that it controlled the self-renewal of leukemic and breast cancer stem cell and was overexpressed in some solid tumors and hematologic malignancies. In this study, the effects of inactivation of Bmi-1 mediated by a plasmid-expressing antisense Bmi-1 RNA on the proliferation of lung cancer cell line A549 were investigated. As a result, when the plasmid was stably introduced into the cell line, the Bmi-1 protein level was specifically downregulated, and the cell proliferation was significantly inhibited as shown by the cell growth curve and colony forming assay. The cells were found mostly in the phase of G(0)/G(1) and cells in S phase were significantly decreased. Our results suggest that targeting Bmi-1 might be a therapeutic potential for the treatment of non-small-cell lung cancer.

VP-16 resistance in the NCI-H460 human lung cancer cell line is significantly associated with glucose-regulated protein78 (GRP78) induction.

AIM: To investigate the relationship between the expression of glucose-regulated protein (GRP78) and resistance to VP-16 in the NCI-H460 cell line. METHODS: RT-PCR, real-time RT-PCR and Western blotting were used in analyzing the expression of GRP78 at mRNA and protein levels in the NCI-H460 cell line induced by A23187 at different concentrations. Cell survival with VP-16 was determined using a colony-formation assay with the account of IC50. RESULTS: The expression of GRP78 at both the mRNA and protein levels was higher in the NCI-H460 cell line induced by A23187. A23187 treatment resulted in up to 4.8-fold elevation of GRP78 mRNA and up to 3.2-fold elevation of GRP78 protein in the experimental cells compared to the controls, all in a dose-dependent manner. The IC50s for VP-16 in the cells pretreated with different concentrations of A23187 (0, 1, 2, 4 and 6 microM) were: 12.11 +/- 0.83, 12.68 +/- 1.04, 25.82 +/- 1.83, 37.46 +/- 1.89 and 45.19 +/- 2.34 microM, respectively. Compared to the control, there was a significant elevation of IC50 for VP-16 in the cells pretreated with A23187. Survival curve analysis also showed that the induction of A23187 caused a significantly longer survival for the cells subjected to VP-16 treatment (p < 0.05). CONCLUSION: A23187 treatment is highly effective for the induction of GRP78 and subsequent development of resistance to VP-16 in the human lung cancer NCI-H460 cell line. Based on the trend of the change in IC50 and the expression of GRP78 in differently exposed cells, we conclude that the induction of GRP78 by A23187 is significantly associated with the resistance to VP-16.

[Relationship between chemosensitivity in vitro and the expression of GRP78 in non-small cell lung cancer].

BACKGROUND: The expressive level of glucose-regulated protein 78 (GRP78) is elevated and correlated with resistance of chemotherapy drugs in breast cancer cell. However, little is known about the relationship between its expression and drug resistance in non-small cell lung cancer (NSCLC). The aim of this study was to explore the relationship between drug resistance and the expression of GRP78 in NSCLC. METHODS: Drug sensitivity test was used to detect the resistance to 8 chemotherapy drugs in 52 NSCLC fresh surgical samples by methylthiazoletrazolium (MTT), and expression of GRP78 was detected by immunohistochemistry method. Spearman correlation assay was used to investigate the correlation between the GRP78 expression and drug resistance. RESULTS: The resistance rates to paclitaxel (PTX), adriamycin (ADM), carboplatin (CBP), topotecan (TPT), navelbine (NVB), vincristine (VCR), cisplatin (DDP) and etoposide (VP-16) of the 52 samples were 42.31%, 57.69%, 63.46%, 65.38%, 67.31%, 73.08%, 78.85%, 90.38%, respectively. Fourteen cases showed the complete resistance to the total 8 chemotherapy drugs. Furthermore, the expression of GRP78 was stronger in poorly differentiated cancer as compared with the well and moderately differentiated cancer (P < 0.05), so as in stage II and III cancer than in stage I cancer (P < 0.05). Spearman correlation assay showed that there was a correlation between the chemotherapeutics resistance to ADM, VP-16, VCR, TPT and the expression of GRP78 in NSCLC (P < 0.05). CONCLUSIONS: It is feasible to detect the drug sensitivity to chemotherapy for tumor cells by MTT method. The results of chemosensitivity assay in vitro are indicative of clinical drug administration in NSCLC. The detection of GRP78 isalso indicative of the resistance to chemotherapy drugs and the differentiation and the clinical stage in NSCLC.