Detection of miR-155-5p and imaging lung cancer for early diagnosis: in vitro and in vivo study.

PURPOSE: Currently, the routine screening program has insufficient capacity for the early diagnosis of lung cancer. Therefore, a type of chitosan-molecular beacon (CS-MB) probe was developed to recognize the miR-155-5p and image the lung cancer cells for the early diagnosis. METHODS: Based on the molecular beacon (MB) technology and nanotechnology, the CS-MB probe was synthesized self-assembly. There are four types of cells-three kinds of animal models and one type of histopathological sections of human lung cancer were utilized as models, including A549, SPC-A1, H446 lung cancer cells, tumor-initiating cells (TICs), subcutaneous and lung xenografts mice, and lox-stop-lox(LSL) K-ras G12D transgenic mice. The transgenic mice dynamically displayed the process from normal lung tissues to atypical hyperplasia, adenoma, carcinoma in situ, and adenocarcinoma. The different miR-155-5p expression levels in these cells and models were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The CS-MB probe was used to recognize the miR-155-5p and image the lung cancer cells by confocal microscopy in vitro and by living imaging system in vivo. RESULTS: The CS-MB probe could be used to recognize the miR-155-5p and image the lung cancer cells significantly in these cells and models. The fluorescence intensity trends detected by the CS-MB probe were similar to the expression levels trends of miR-155 tested by qRT-PCR. Moreover, the fluorescence intensity showed an increasing trend with the tumor progression in the transgenic mice model, and the occurrence and development of lung cancer were dynamically monitored by the differen fluorescence intensity. In addition, the miR-155-5p in human lung cancer tissues could be detected by the miR-155-5p MB. CONCLUSION: Both in vivo and in vitro experiments demonstrated that the CS-MB probe could be utilized to recognize the miR-155-5p and image the lung cancer cells. It provided a novel experimental and theoretical basis for the early diagnosis of the disease. Also, the histopathological sections of human lung cancer research laid the foundation for subsequent preclinical studies. In addition, different MBs could be designed to detect other miRNAs for the early diagnosis of other tumors.

Case report: primary resistance to osimertinib in erlotinib-pretreated lung adenocarcinoma with EGFR T790 M mutation.

BACKGROUND: Among non-small cell lung cancer (NSCLC) patients with acquired T790 M mutation resistance to first-generation epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI), 71% are likely to benefit from osimertinib. There have been several reports about the secondary resistance to osimertinib treatment in T790 M-positive patients, while primary resistance to osimertinib has been rarely reported. CASE PRESENTATION: A 62-year-old Asian male never smoker who presented with stage IV EGFR L858R-positive adenocarcinoma developed EGFR T790 M mutation after 14 months of treatment with erlotinib combined with thoracic radiotherapy as first-line therapy. The patient was initiated on osimertinib treatment with T790 M mutation detected (14.4%), but disease progressed 2 months later. CONCLUSION: The mechanism of primary resistance to osimertinib remains unclear. There may be an association between T790 M mutation disappearance, TP53 mutation and radiotherapy, but further researches are needed to confirm this.

A dosimetric phantom study of thoracic radiotherapy based on three-dimensional modeling of mediastinal lymph nodes.

The aim of the present study was to investigate the optimal strategy and dosimetric measurement of thoracic radiotherapy based on three-dimensional (3D) modeling of mediastinal lymph nodes (MLNs). A 3D model of MLNs was constructed from a Chinese Visible Human female dataset. Image registration and fusion between reconstructed MLNs and original chest computed tomography (CT) images was conducted in the Eclipse™ treatment planning system (TPS). There were three plans, including 3D conformal radiotherapy (3D-CRT), intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (VMAT), which were designed based on 10 cases of simulated lung lesions (SLLs) and MLNs. The quality of these plans was evaluated via examining indexes, including conformity index (CI), homogeneity index and clinical target volume (CTV) coverage. Dose-volume histogram analysis was performed on SLL, MLNs and organs at risk (OARs). A Chengdu Dosimetric Phantom (CDP) was then drilled at specific MLNs according to 20 patients with thoracic tumors and of a medium-build. These plans were repeated on fused MLNs and CDP CT images in the Eclipse™ TPS. Radiation doses at the SLLs and MLNs of the CDP were measured and compared with calculated doses. The established 3D MLN model demonstrated the spatial location of MLNs and adjacent structures. Precise image registration and fusion were conducted between reconstructed MLNs and the original chest CT or CDP CT images. IMRT demonstrated greater values in CI, CTV coverage and OAR (lungs and spinal cord) protection, compared with 3D-CRT and VMAT (P<0.05). The deviation between the measured and calculated doses was within ± 10% at SLL, and at the 2R and 7th MLN stations. In conclusion, the 3D MLN model can benefit plan optimization and dosimetric measurement of thoracic radiotherapy, and when combined with CDP, it may provide a tool for clinical dosimetric monitoring.

Identification and imaging of miR-155 in the early screening of lung cancer by targeted delivery of octreotide-conjugated chitosan-molecular beacon nanoparticles.

Lung cancer is still the most common cancer globally. Early screening remains the key to improve the prognosis of patients. There is currently a lack of specific and sensitive methods for early screening of lung cancer. In recent years, studies have found that microRNA plays an important role in the occurrence and development of lung cancer and become a biological target in the early diagnosis of lung cancer. In this study, lung cancer cells, subcutaneous xenografts of lung cancer in nude mice, and Lox-Stop-lox K-ras G12D transgenic mice were used as models. The transgenic mice displayed the dynamic processes from normal lung tissue to atypical hyperplasia, adenomas, carcinoma in situ and lung adenocarcinoma. It was found that miR-155 and somatostatin receptor 2 (SSTR2) were expressed in all the disease stages of transgenic mice. Through molecular beacon (MB) technology and nanotechnology, chitosan-molecular beacon (CS-MB) nanoparticles and targeted octreotide (OCT) were conjugated and synthesized. The octreotide-conjugated chitosan-molecular beacon nanoparticles (CS-MB-OCT) can specifically bind to SSTR2 expressed by the lung cancer cells to achieve the goal of identification of lung cancer cells and imaging miR-155 in vivo and in vitro. Fluorescence imaging at different disease stages of lung cancer in Lox-Stop-lox K-ras G12D transgenic mice was performed, and could dynamically monitor the occurrence and development of lung cancer by different fluorescence intensity ranges. The current research, in turn, provides new idea, new method, and new technology for the early screening of lung cancer.

miR-223 enhances the sensitivity of non-small cell lung cancer cells to erlotinib by targeting the insulin-like growth factor-1 receptor.

Lung cancer is the leading cause of cancer-related fatalities worldwide, and non-small cell lung cancer (NSCLC) is the main pathological type. MicroRNAs (miRNAs or miRs) are a class of small non-coding RNAs, which are involved in tumor initiation and progression. miR­223 is a tumor suppressor miRNA that has been reported in various types of cancer, including lung cancer. In the present study, to characterize the biological behavior of miR­223 in NSCLC, we established an miR­223 overexpression model in erlotinib-resistant PC­9 (PC­9/ER) cells by infection with lentivirus to induce the overexpression of miR­223. As a result, miR­223 enhanced the sensitivity of the PC­9/ER cells to erlotinib by inducing apoptosis in vitro. Additionally, in vivo experiments were performed using nude mice which were injected with the cancer cells [either the PC­9 (not resistant), PC­9/ER, or the PC­9/ER cells infected with miR­223)]. We found that the tumor volumes were reduced in the rats injected with the cells infected with miR­223. To further explore the underlying mechanisms, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis were used to identify the target molecules of miR­223. miR­223 was demonstrated to act as a local regulator of insulin-like growth factor-1 receptor (IGF-1R) in the acquired resistance to tyrosine kinase inhibitors (TKIs). Notably, the οverexpression of IGF-1R in NSCLC was downregulated by miR­223, and the activation of Akt/S6, the downstream pathway, was also inhibited. The inhibition of IGF-1R by miR­223 was attenuated by exogenous IGF-1 expression. Therefore, miR­223 may regulate the acquired resistance of PC­9/ER cells to erlotinib by targeting the IGF-1R/Akt/S6 signaling pathway. The overexpression of miR­223 may partially reverse the acquired resistance to epidermal growth factor receptor-TKIs, thus, providing a potential therapeutic strategy for TKI-resistant NSCLC.

Essential role of miR-200c in regulating self-renewal of breast cancer stem cells and their counterparts of mammary epithelium.

BACKGROUND: Breast cancer stem cells (BCSCs) have been reported as the origin of breast cancer and the radical cause of drug resistance, relapse and metastasis in breast cancer. BCSCs could be derived from mutated mammary epithelial stem cells (MaSCs). Therefore, comparing the molecular differences between BCSCs and MaSCs may clarify the mechanism underlying breast carcinogenesis and the targets for gene therapy. Specifically, the distinct miRNome data of BCSCs and MaSCs need to be analyzed to find out the key miRNAs and reveal their roles in regulating the stemness of BCSCs. METHODS: MUC1(-)ESA(+) cells were isolated from normal mammary epithelial cell line MCF-10A by fluorescence-activated cell sorting (FACS) and tested for stemness by clonogenic assay and multi-potential differentiation experiments. The miRNA profiles of MaSCs, BCSCs and breast cancer MCF-7 cells were compared to obtain the candidate miRNAs that may regulate breast tumorigenesis. An miRNA consecutively upregulated from MaSCs to BCSCs to MCF-7 cells, miR-200c, was chosen to determine its role in regulating the stemness of BCSCs and MaSCs in vitro and in vivo. Based on bioinformatics, the targets of miR-200c were validated by dual-luciferase report system, western blot and rescue experiments. RESULTS: In a 2-D clonogenic assay, MUC1(-)ESA(+) cells gave rise to multiple morphological colonies, including luminal colonies, myoepithelial colonies and mixed colonies. The clonogenic potential of MUC1(-)ESA(+) (61.5 ± 3.87 %) was significantly higher than that of non-stem MCF-10A cells (53.5 ± 3.42 %) (P < 0.05). In a 3-D matrigel culture, MUC1(-)ESA(+) cells grew into mammospheres with duct-like structures. A total of 12 miRNAs of interest were identified, 8 of which were upregulated and 4 downregulated in BCSCs compared with MaSCs. In gain- and lost-of-function assays, miR-200c was sufficient to inhibit the self-renewal of BCSCs and MaSCs in vitro and the growth of BCSCs in vivo. Furthermore, miR-200c negatively regulated programmed cell death 10 (PDCD10) in BCSCs and MaSCs. PDCD10 could rescue the tumorigenesis inhibited by miR-200c in BCSCs. DISCUSSION: Accumulating evidence shows that there is a milignant transformation from MaSCs into BCSCs. The underlying mechanism remains unclear. In present study, miRNA profiles between MaSCs and BCSCs were obtained. Then miRNA-200c, downregulated in both MaSCs and BCSCs, were verified as anti-oncogene, and played essential role in regulating self-renewal of both kinds of stem-like cells. These findings reveal a novel insights of breast tumorigenesis. CONCLUSIONS: PDCD10 is a target gene of miR-200c and also a possible mechanism by which miR-200c plays a role in regulating the stemness of BCSCs and MaSCs.

MicroRNA profile of tumorigenic cells during carcinogenesis of lung adenocarcinoma.

To obtain microRNA (miRNA) profile and clarify their biological function in tumorigenic Sca-1(+) CD34(+) cells during carcinogenesis of lung adenocarcinoma. After intranasal infection with recombinant Adeno-Cre viruses (AdV-Cre), lung adenocarcinoma was identified pathologically in Lox-stop-lox Kras (LSL-Kras) G12D mice. Sca-1(+) CD34(+) cells were sorted by flow cytometry and tested for tumor-initiating ability, self-renewal and tumorigenicity. MiRNA profiles were obtained using microarray and further confirmed by real-time RT-PCR (qRT-PCR). MiRNA functions were predicted bioinformatically, and miR-294 function was verified to explore its role in tumor migration and invasion. Lung adenocarcinoma was induced in LSL-Kras G12D mice within 30 days. In vivo, the tumorigenicity of Sca-1(+) CD34(+) cells was 25 times stronger than Sca-1(-) CD34(-) cells. During tumorigenesis of lung adenocarcinoma, the expression of 145 miRNAs in Sca-1(+) CD34(+) cells increased and 72 miRNAs decreased (P < 0.01). Four successively up-regulated miRNAs (miR-15a*, miR-203, miR-294 and miR-295*) and three successively down-regulated ones (miR-19b, miR-483 and miR-615-5p) were identified. Among them, miR-294 could constitutively bind to 3'-UTR of matrix metalloproteinase 3 (MMP3), and down-regulate MMP3 protein expression. MiR-294 also significantly inhibited migration and invasion of Lewis lung cancer cells. MiRNAs are characteristically expressed in tumor-initiating Sca-1(+) CD34(+) cells of lung adenocarcinoma, and may play important roles during the carcinogenesis of lung adenocarcinoma.

Chitosan combined with molecular beacon for mir-155 detection and imaging in lung cancer.

Lung cancer is the major cause of cancer-related deaths worldwide, thus developing effective methods for its early diagnosis is urgently needed. In recent years, microRNAs (miRNAs, miR) have been reported to play important roles in carcinogenesis and have become potential biomarkers for cancer diagnosis and treatment. Molecular beacon (MB) technology is a universal technology to detect DNA/RNA expression in living cells. As a natural polymers, chitosan (CS) nanoparticles could be used as a carrier for safe delivery of nucleic acid. In this study, we developed a probe using nanoparticles of miR-155 MB self assembled with CS (CS-miR-155 MB) to image the expression of miR-155 in cancer cells. Hybridization assay showed that the locked nucleic acid (LAN) modified miR-155 MB could target miR-155 effectively and sensitively. The miR-155 MB self-assembly with CS nanoparticles formed stable complexes at the proper weight ratio. The CS nanoparticles showed higher fluorescence intensity and transfection efficiency than the lipid-based formulation transfection agent by confocal microscopy and flow cytometry analysis. The CS-MB complexes were found to be easily synthesized and exhibited strong enzymatic stability, efficient cellular uptake, high target selectivity and biocompatibility. The CS-MB complexes can also be applied in other cancers just by simply changing for a targeted miRNA highly expressed in those cancer cells. Therefore, it is a promising vehicle used for detecting miRNA expression in living cells.

Monitoring microRNAs using a molecular beacon in CD133+/ CD338+ human lung adenocarcinoma-initiating A549 cells.

Lung cancer is the most common causes of cancer-related deaths worldwide, and a lack of effective methods for early diagnosis has greatly impacted the prognosis and survival rates of the affected patients. Tumor-initiating cells (TICs) are considered to be largely responsible for tumor genesis, resistance to tumor therapy, metastasis, and recurrence. In addition to representing a good potential treatment target, TICs can provide clues for the early diagnosis of cancer. MicroRNA (miRNA) alterations are known to be involved in the initiation and progression of human cancer, and the detection of related miRNAs in TICs is an important strategy for lung cancer early diagnosis. As Hsa-miR-155 (miR-155) can be used as a diagnostic marker for non-small cell lung cancer (NSCLC), a smart molecular beacon of miR-155 was designed to image the expression of miR-155 in NSCLC cases. TICs expressing CD133 and CD338 were obtained from A549 cells by applying an immune magnetic bead isolation system, and miR-155 was detected using laser-scanning confocal microscopy. We found that intracellular miR- 155 could be successfully detected using smart miR-155 molecular beacons. Expression was higher in TICs than in A549 cells, indicating that miR-155 may play an important role in regulating bio-behavior of TICs. As a non-invasive approach, molecular beacons could be implemented with molecular imaging to diagnose lung cancer at early stages.

Identifying differentially expressed genes and screening small molecule drugs for lapatinib-resistance of breast cancer by a bioinformatics strategy.

BACKGROUND: Lapatinib, a dual tyrosine kinase inhibitor that interrupts the epidermal growth factor receptor (EGFR) and HER2/neu pathways, has been indicated to have significant efficacy in treating HER2-positive breast cancer. However, acquired drug resistance has become a very serious clinical problem that hampers the use of this agent. In this study, we aimed to screen small molecule drugs that might reverse lapatinib-resistance of breast cancer by exploring differentially expressed genes (DEGs) via a bioinformatics method. MATERIALS AND METHODS: We downloaded the gene expression profile of BT474-J4 (acquired lapatinib-resistant) and BT474 (lapatinib-sensitive) cell lines from the Gene Expression Omnibus (GEO) database and selected differentially expressed genes (DEGs) using dChip software. Then, gene ontology and pathway enrichment analyses were performed with the DAVID database. Finally, a connectivity map was utilized for predicting potential chemicals that reverse lapatinib-resistance. RESULTS: A total of 1, 657 DEGs were obtained. These DEGs were enriched in 10 pathways, including cell cycling, regulation of actin cytoskeleton and focal adhesion associate examples. In addition, several small molecules were screened as the potential therapeutic agents capable of overcoming lapatinib-resistance. CONCLUSIONS: The results of our analysis provided a novel strategy for investigating the mechanism of lapatinib-resistance and identifying potential small molecule drugs for breast cancer treatment.

CCND1 G870A polymorphism interaction with cigarette smoking increases lung cancer risk: meta-analyses based on 5008 cases and 5214 controls.

Evidence indicates CCND1 G870A polymorphisms as a risk factor for a number of cancers. Increasing studies have been conducted on the association of CCND1 G870A polymorphism with lung cancer risk. However, the results were controversial. The aim of the present study was to derive a more precise estimation of the relationship. Meta-analyses examining the association between CCND1 G870A polymorphism and lung cancer were performed. Subgroup analyses regarding ethnicity, smoking status, histological types and source of controls were also implemented. All eligible studies for the period up to May 2012 were identified. The overall data from ten case-control studies including 5,008 cases and 5,214 controls indicated that variant A allele may have an association with increased lung cancer risk (AA vs GG: OR = 1.21; 95 % CI = 1.08-1.36, dominant model: OR = 1.09; 95 % CI = 1.00-1.19, recessive model: OR = 1.23; 95 % CI = 1.01-1.49). In the subgroup analysis by ethnicity, A allele may elevate lung cancer risk among Asians but not Caucasians or Mixed ethnicities. In smoking status subgroup, A allele was shown to associate with increased lung cancer risk among smokers but not non-smokers. In the subgroup analysis by histological types, increased cancer risks were shown in adenocarcinoma but not squamous cell carcinoma, under the homozygote comparison and recessive models. Collectively, the results of the present study suggest that CCND1 G870A polymorphism might be a low-penetrant risk factor for lung cancer, particularly among Asians and smokers. Moreover, homozygous AA alleles might have a correlation with increased lung adenocarcinoma susceptibility.

Long-term results of a randomized, double-blind, and placebo-controlled phase III trial: Endostar (rh-endostatin) versus placebo in combination with vinorelbine and cisplatin in advanced non-small cell lung cancer.

BACKGROUND: : Phase II-III trials in patients with untreated and previously treated locally advanced or non-small cell lung cancer (NSCLC) suggested that Endostar was able to enhance the effect of platinum-based chemotherapy (NP regimen) with tolerable adverse effects. METHODS: Four hundred and eighty six patients were randomized into two arms: study arm A: NP plus Endostar (n = 322; vinorelbine, cisplatin, Endostar), and study arm B: NP plus placebo (n = 164; vinorelbine, cisplatin, 0.9% sodium chloride). Patients were treated every third week for two to six cycles. RESULTS: : Overall response rates were 35.4% in arm A and 19.5% in arm B (P = 0.0003). The median time to progression was 6.3 months for arm A and 3.6 months for B, respectively (P < 0.001). The clinical benefit rates were 73.3% in arm A and 64.0% in arm B (P = 0.035). Grade 3/4 neutropenia, anemia, and nausea/vomiting were 28.5%, 3.4%, and 8.0%, respectively, in Arm A compared with 28.2%, 3.0%, and 6.6%, respectively, in Arm B (P > 0.05). There were two treatment related deaths in arm A and one in arm B (P > 0.05). The median overall survival was longer in arm A than in arm B (P < 0.0001). CONCLUSION: : Long-term follow-up revealed that the addition of Endostar to an NP regimen can result in a significant clinical and survival benefit in advanced NSCLC patients, compared with NP alone.

Increased treatment-related mortality with additional cisplatin-based chemotherapy in patients with nasopharyngeal carcinoma treated with standard radiotherapy.

BACKGROUND AND PURPOSES: We performed a meta-analysis of randomized controlled trials (RCTs) to determine the overall risk of treatment-related death associated with additional cisplatin-based chemotherapy in patients with nasopharyngeal carcinoma treated with standard radiotherapy. MATERIAL AND METHODS: Eligible studies included RCTs in which cisplatin-based chemotherapy in combination with radiotherapy was compared with radiotherapy alone. Statistical analyses were conducted to calculate the summary incidence rates, relative risks (RRs), and 95% confidence intervals (CIs) using fixed- or random-effects models based on the heterogeneity of included studies. RESULTS: A total of 2829 patients from 13 RCTs were included in this study. The overall incidence for treatment-related death in chemoradiotherapy and radiotherapy treated patients was 1.7% and 0.8%. Compared to radiotherapy alone, radiotherapy plus cisplatin-based chemotherapy significantly increased the risk of treatment-related mortality. On subgroup analyses, no difference was found in treatment-related mortality between different timings of chemotherapy and chemotherapeutic agents. Adding cisplatin-based chemotherapy was associated with higher incidences of severe acute toxicity. CONCLUSIONS: Cisplatin-based chemotherapy plus radiotherapy increased the risk of treatment-related death and severe acute toxicity, compared with radiotherapy alone. Better management of treatment toxicity might improve the therapeutic gain in patients with nasopharyngeal carcinoma.

Prediction of radiation pneumonitis in lung cancer patients: a systematic review.

PURPOSE: Factors prediction in the development of radiation pneumonitis (RP) remains unclear. A meta-analysis about this was performed. MATERIALS: Articles were searched in February 2012 from PubMed, EMBASE, Cochrane Library and CNKI (Chinese Journal Full-text Database) using the keywords "lung cancer," "radiation pneumonitis" or "radiation lung injury." The outcome was the RP incidence. We pooled the data using RevMan 5.1 software and tested the statistical heterogeneity. RESULTS: We included the following factors: age, gender, weight loss, smoking history, complications, performance status, pre-radiation therapy (RT) pulmonary function, TNM, histological type, tumor location, pre-RT surgery, RT combined with chemotherapy (RCT), RT/RCT combined with amifostine, plasma end/pre-RT TGF-ß1 ratio and irradiation volume. The significant risk factors for RP ≥ grade 2 were patients with chronic lung disease, tumor located in the middle or lower lobe, without pre-RT surgery, RCT, plasma end/pre-RT TGF-ß1 ratio ≥1 and gross tumor volume (GTV). Following factors were identified significant for RP, including tumor located not in the upper lobe, smokers, combined with chronic lung diseases or diabetes mellitus, low pre-RT pulmonary function, RCT, RT/RCT without amifostine and plasma end/pre-RT TGF-ß1 ratio ≥1. Dose-volume parameters included the average of mean lung dose (MLD) of disease lung, GTV and V (5), V (10) (≥34 %), V (20) (≥25 %), V (30) (≥18 %) of bilateral lung. CONCLUSIONS: More attention should be paid to the levels of patients' pulmonary function, plasma TGF-ß1 and dose-volume histogram (DVH). Rigorous studies are needed to identify the relationship between the above-mentioned factors and RP ≥grade 1 or 3.

Novel molecular beacons to monitor microRNAs in non-small-cell lung cancer.

Lung cancer is the leading cause of cancer death worldwide. There is no effective early diagnostic technology for lung cancer. microRNAs (miRNAs) are noncoding RNA molecules which regulate the process of cell growth and differentiation in human cancers. Hsa-miR-155 (miR-155), highly expressed in non-small-cell lung cancer (NSCLC), can be used as a diagnostic marker for NSCLC. Dynamic observation of miR-155 is critical to diagnose NSCLC. A novel molecular beacon (MB) of miR-155 was designed to image the expression of miR-155 in NSCLC. Then miR-155 was detected in vitro by laser confocal microscopy and in vivo by stereomicroscope imaging system, respectively. The present study demonstrated that intracellular miR-155 could be successfully and quickly detected by novel miR-155 MBs. As a noninvasive monitoring approach, MBs could be used to diagnose lung cancer at early stage through molecular imaging.

MTHFR C677T and A1298C polymorphisms and cervical carcinoma susceptibility: meta-analyses based on 4,421 individuals.

MTHFR polymorphisms have been implicated as risk factors for several cancers. Studies have conducted on the associations of MTHFR polymorphisms with cervical carcinoma risk and have generated inconclusive results. The aim of the present study was to increase power demonstrating the possible relations. Meta-analyses examining the association between MTHFR C677T and A1298C polymorphisms and cervical carcinoma risk were performed. Separate analyses on ethnicity and source of controls were also implemented. Eligible studies were identified for the period up to Dec 2011. Eleven case-control studies containing 1859 cases and 2562 controls regarding MTHFR C677T polymorphisms were selected, of which four studies containing 461 cases and 832 controls described A1298C polymorphisms. For the overall data, no associations of MTHFR C677T polymorphisms with cervical carcinoma were observed (TT vs CC: OR = 1.07; 95 %CI = 0.73-1.58; dominant model: OR = 0.89; 95 %CI = 0.66-1.18; recessive model: OR = 1.13; 95 %CI = 0.84-1.52). In the subgroup analysis by ethnicity, MTHFR 677T allele was associated with decreased cervical cancer susceptibility among Caucasians (TT vs CC: OR = 0.65; 95 %CI = 0.45-0.93; dominant model: OR = 0.70; 95 %CI = 0.58-0.86) but not Asians. As for A1298C polymorphism, no marked associations of A1298C genetic variation with cervical cancer risk were observed (CC vs AA: OR = 1.01; 95 %CI = 0.60-1.73; dominant model: OR = 1.17; 95 %CI = 0.91-1.49; recessive model: OR = 0.99; 95 %CI = 0.60-1.63). Collectively, the results of the present study suggest that MTHFR 677T allele might play a preventive role for cervical carcinoma among Caucasians. A1298C polymorphisms might exert little effect on cervical cancerigenesis.

Identification of a cancer stem-like population in the Lewis lung cancer cell line.

OBJECTIVE: Although various human cancer stem cells (CSCs) have been defined, their applications are restricted to immunocompromised models. Developing a novel CSC model which could be used in immunocompetent or transgenic mice is essential for further understanding of the biomolecular characteristics of tumor stem cells. Therefore, in this study, we analyzed murine lung cancer cells for the presence of CSCs. METHODS: Side population (SP) cells were isolated by fluorescence activated cell sorting, followed by serum-free medium (SFM) culture, using Lewis lung carcinoma cell (LLC) line. The self-renewal, differentiated progeny, chemosensitivity, and tumorigenic properties in SP and non-SP cells were investigated through in vitro culture and in vivo serial transplantation. Differential expression profiles of stem cell markers were examined by RT-PCR. RESULTS: The SP cell fraction comprised 1.1% of the total LLC population. SP cells were available to grow in SFM, and had significantly enhanced capacity for cell proliferation and colony formation. They were also more resistant to cisplatin in comparison to non-SP cells, and displayed increased tumorigenic ability. Moreover, SP cells showed higher mRNA expression of Oct-4, ABCG2, and CD44. CONCLUSION: We identified SP cells from a murine lung carcinoma, which possess well-known characteristics of CSCs. Our study established a useful model that should allow investigation of the biological features and pharmacosensitivity of lung CSCs, both in vitro and in syngeneic immunocompetent or transgenic/knockout mice.

Aberrant microRNAs expression in CD133⁺/CD326⁺ human lung adenocarcinoma initiating cells from A549.

Increasing evidence demonstrates that miRNAs are involved in the dysregulation of tumor initiating cells (TICs) in various tumors. Due to a lack of definitive markers, cell sorting is not an ideal separation method for lung adenocarcinoma initiating cells. In this study, we combined paclitaxel with serum-free medium cultivation (inverse-induction) to enrich TICs from A549 cells, marked by CD133/CD326, defined features of stemness. We next investigated aberrant microRNAs in this subpopulation compared to normal cells with miRNA microarray and found that 50 miRNAs exhibited a greater than 2-fold change in expression. As further validation, 10 miRNAs were chosen to perform quantitative RT-PCR on the A549 cell line and primary samples. The results suggest that aberrant expression of miRNAs such as miR-29ab, miR-183, miR-17-5p and miR-127-3P may play an important role in regulating the bio-behavior of TICs.

Comparison of total body irradiation before and after chemotherapy in pretreatment for hematopoietic stem cell transplantation.

OBJECTIVE: To explore the best time to carry out total body irradiation (TBI) in hematopoietic stem cell transplantation (HSCT) pretreatment. METHODS: Retrospective analysis was applied in 88 cases of HSCT using TBI as pretreatment from March 2001 to June 2009 in our hospital. Using 8 MV X-ray, all the patients were irradiated by linear accelerator in 2 consecutive days, with a total dose of 7-11 Gy and an instantaneous dose rate ranging between 4.0 and 5.0 cGy/min. Of the 88 cases, 40 cases were given traditional high-dose chemotherapy before TBI (Group CT/TBI), and 48 cases were given TBI before chemotherapy (Group TBI/CT) instead. RESULTS: Eighty-seven cases of transplantation were successful, with no serious complications, including radiation pneumonia. Compared with Group CT/TBI, Group TBI/CT showed similar incidence of complications (p=0.08), similar recent chemotherapy toxicity (p=0.833), and significantly lower recent radiation toxicity (p=0.000). CONCLUSIONS: TBI in the pretreatment of HSCT is safe and effective. Using TBI before the high-dose chemotherapy can maintain the same pretreatment effect, effectively reduce apparent immediate reaction/discomfort during TBI, reduce preparation workload of radiotherapy, and lower radiation side-effects. Further research is needed to expand its clinical application.