[Effect of Oral Glutamine on Chemotherapy-Induced Peripheral Neuropathy in Cancer Patients: An Evidence-Based Appraisal].

BACKGROUND: Chemotherapy may induce peripheral neuropathy, which often results in the chemotherapy dose being reduced or the chemotherapy regimen being stopped. At present, there are no treatment guidelines for chemotherapy-induced peripheral neuropathy. Glutamine is one of the treatment strategies currently applied in practice. This strategy is expensive and lacks clear evidence as to its efficacy. PURPOSE: To evaluate the effect of oral glutamine on CIPN in cancer patients. METHODS: PICO (population- intervention- comparison- outcome) was used to focus the problem: P: cancer patient; I: glutamine, L-glutamine; C: usual care; O: alleviate, reduce, improve, and prevent. Databases searched included Airiti Library, Cochrane Library, CINAHL, and PubMed. Three randomized clinical trials and two quasi-experimental designs were evaluated using evidence-based appraisal. RESULTS: Four studies used 30 g/day of glutamine either at the beginning of chemotherapy or at 24 hours after the beginning of chemotherapy. The shortest duration for taking glutamine was four days and longest duration was two months. The incidences of CIPN-induced pain were significantly different (risk ratio = 0.26; 95% CI [0.09, 0.70], Z = 2.65, p = .008) between the intervention and control groups. The incidences of CIPN grading, numbness, and muscle weakness were not significantly different between the intervention and control groups. From an economic point of view, the clinical efficacy of taking glutamine does not justify the additional daily cost to the patient of NT¤500 (about US¤17). CONCLUSIONS / IMPLICATIONS FOR PRACTICE: Because of the small sample size, minimal effects of glutamine, and no significant decrease in risk, we do not suggest routinely using oral glutamine to prevent or reduce CIPN symptoms in cancer patients.

Precancerous esophageal epithelia are associated with significantly increased scattering coefficients.

The progression of epithelial precancers into cancer is accompanied by changes of tissue and cellular structures in the epithelium. Correlations between the structural changes and scattering coefficients of esophageal epithelia were investigated using quantitative phase images and the scattering-phase theorem. An ex vivo study of 14 patients demonstrated that the average scattering coefficient of precancerous epithelia was 37.8% higher than that of normal epithelia from the same patient. The scattering coefficients were highly correlated with morphological features including the cell density and the nuclear-to-cytoplasmic ratio. A high interpatient variability in scattering coefficients was observed and suggests identifying precancerous lesions based on the relative change in scattering coefficients.

In vivo expression patterns of microRNAs of Gallid herpesvirus 2 (GaHV-2) during the virus life cycle and development of Marek's disease lymphomas.

In the past decade, a large number of microRNAs (miRNAs) have been identified in the viral genome of Gallid herpesvirus 2 (GaHV-2), which is historically known as Marek's disease virus type 1. The biological role of most GaHV-2 miRNAs remains unclear. In the present study, we have performed an overall gene expression profile of GaHV-2 miRNAs during the virus life cycle at each phase of the developing disease, a highly contagious, lymphoproliferative disorder, and neoplastic immunosuppressive disease of poultry known as the Marek's disease. According to their distinct in vivo expression patterns, the GaHV-2 miRNAs can be divided into three groups: 12 miRNAs in group I, including miR-M4-5p, displayed a typical expression pattern potentially correlated to the latent, late cytolytic, and/or the proliferative phases in the cycle of GaHV-2 pathogenesis; group II consisting of another 12 miRNAs with expression correlated to the early cytolytic and/or latent phases in GaHV-2's life cycle; while the other two miRNAs in group III showed no identical expression features. Our findings may provide meaningful clues in the search for further potential functions of viral miRNAs in GaHV-2 biology.

Marek's disease virus-encoded analog of microRNA-155 activates the oncogene c-Myc by targeting LTBP1 and suppressing the TGF-ß signaling pathway.

Marek's disease virus (MDV) is a representative alpha herpes virus able to induce rapid-onset T-cell lymphoma in its natural host and regarded as an ideal model for the study of virus-induced tumorigenesis. Recent studies have shown that the mdv1-miR-M4-5p, a viral analog of cellular miR-155, is critical for MDV׳s oncogenicity. However, the precise mechanism whereby it was involved in MD lymphomagenesis remained unknown. We have presently identified the host mRNA targets of mdv1-miR-M4-5 and identified the latent TGF-ß binding protein 1 (LTBP1) as a critical target for it. We found that during MDV infection, down-regulation of LTBP1 expression by mdv1-miR-M4-5p led to a significant decrease of the secretion and activation of TGF-ß1, with suppression of TGF-ß signaling and a significant activation of expression of c-Myc, a well-known oncogene which is critical for virus-induced tumorigenesis. Our findings reveal a novel and important mechanism of how mdv1-miR-M4-5p potentially contributes to MDV-induced tumorigenesis.

The significance of the individual Meq-clustered miRNAs of Marek's disease virus in oncogenesis.

Marek's disease virus (MDV) is an important oncogenic alphaherpesvirus that induces rapid-onset T-cell lymphomas in its natural hosts. The Meq-clustered miRNAs encoded by MDV have been suggested to play potentially critical roles in the induction of lymphomas. Using the technique of bacterial artificial chromosome mutagenesis, we have presently constructed a series of specific miRNA-deleted mutants and demonstrate that these miRNAs are not essential for replication of MDV and have no effects on the early cytolytic or latent phases of the developing disease. However, compared to the parental GX0101, mortality of birds infected with the mutants GXΔmiR-M2, GXΔmiR-M3, GXΔmiR-M5, GXΔmiR-M9 and GXΔmiR-M12 was reduced from 100 % to 18 %, 30 %, 48 %, 24 % and 14 %, coupled with gross tumour incidence reduction from 28 % to 8 %, 4 %, 12 %, 8 % and 0 %, respectively. Our data confirm that except for mdv1-miR-M4, the other Meq-clustered miRNAs also play critical roles in MDV oncogenesis. Further work will be needed to elucidate the miRNA-mediated regulatory mechanisms that trigger the development of MD lymphomas.

Investigation of influences of the paraformaldehyde fixation and paraffin embedding removal process on refractive indices and scattering properties of epithelial cells.

The scattering properties and refractive indices (RI) of tissue are important parameters in tissue optics. These parameters can be determined from quantitative phase images of thin slices of tissue blocks. However, the changes in RI and structure of cells due to fixation and paraffin embedding might result in inaccuracies in the estimation of the scattering properties of tissue. In this study, three-dimensional RI distributions of cells were measured using digital holographic microtomography to obtain total scattering cross sections (TSCS) of the cells based on the first-order Born approximation. We investigated the slight loss of dry mass and drastic shrinkage of cells due to paraformaldehyde fixation and paraffin embedding removal processes. We propose a method to compensate for the correlated changes in volume and RI of cells. The results demonstrate that the TSCS of live cells can be estimated using restored cells. The percentage deviation of the TSCS between restored cells and live cells was only −8%. Spatially resolved RI and scattering coefficients of unprocessed oral epithelium ranged from 1.35 to 1.39 and from 100 to 450 cm−1, respectively, estimated from paraffinembedded oral epithelial tissue after restoration of RI and volume.

Tomographic diffractive microscopy of living cells based on a common-path configuration.

We demonstrate a common-path tomographic diffractive microscopy technique for three-dimensional (3D) refractive-index (RI) imaging of unstained living cells. A diffraction grating is utilized to generate a reference beam that traverses a blank region of the sample in a common-path off-axis interferometry setup. Single-shot phase images captured at multiple illumination angles are used for 3D RI reconstruction based on optical diffraction tomography. The common-path configuration shows lower temporal phase fluctuations and better RI resolution than a Mach-Zehnder configuration. 3D subcellular RI distributions of live HeLa cells are quantified.

Molecular characteristics and evolutionary analysis of field Marek's disease virus prevalent in vaccinated chicken flocks in recent years in China.

Marek's disease is a highly contagious, oncogenic, and immunosuppressive avian viral disease. Surveillance of newly registered Marek's disease virus (MDV) isolates is meaningful for revealing the potential factors involved in increased virulence. Presently, we have focused on the molecular characteristics of all available MDVs from China, including 17 new Henan isolates. Based on Meq, gE, and gI genes, we found that most Chinese isolates contain conserved amino acid point mutations in Meq, such as E(77), A(115), A(139), R(176), and A(217), compared to USA virulent MDVs. However, the 59-aa or 60-aa insertions are only found in a few mild MDVs rather than virulent MDVs in China. Further phylogenetic analysis has demonstrated that a different genotype of MDV has been prevalent in China, and for virulent MDVs, their recent evolution has possibly been geographically restricted. Our study has provided more detailed information regarding the field MDVs circulating in China.

[Low dose volume histogram analysis of the lungs in prediction of acute radiation pneumonitis in patients with esophageal cancer treated with three-dimensional conformal radiotherapy].

OBJECTIVE: To investigate the predictive value of low dose volume of the lung on acute radiation pneumonitis (RP) in patients with esophageal cancer treated with three-dimensional conformal radiotherapy (3D-CRT) only, and to analyze the relation of comprehensive parameters of the dose-volume V5, V20 and mean lung dose (MLD) with acute RP. METHODS: Two hundred and twenty-two patients with esophageal cancer treated by 3D-CRT have been followed up. The V5-V30 and MLD were calculated from the dose-volume histogram system. The clinical factors and treatment parameters were collected and analyzed. The acute RP was evaluated according to the RTOG toxicity criteria. RESULTS: The acute RP of grade 1, 2, 3 and 4 were observed in 68 (30.6%), 40 (18.0%), 8 (3.6%) and 1 (0.5%) cases, respectively. The univariate analysis of measurement data:The primary tumor length, radiation fields, MLD and lung V5-V30 had a significant relationship with the acute RP. The magnitude of the number of radiation fields, the volume of GTV, MLD and Lung V5-V30 had a significant difference in whether the ≥ grade 1 and ≥ grade 2 acute RP developed or not. Binary logistic regression analysis showed that MLD, Lung V5, V20 and V25 were independent risk factors of ≥ grade 1 acute RP, and the radiation fields, MLD and Lung V5 were independent risk factors of ≥ grade 2 acute RP. The ≥ grade 1 and ≥ grade 2 acute RP were significantly decreased when MLD less than 14 Gy, V5 and V20 were less than 60% and 28%,respectively. When the V20 ≤ 28%, the acute RP was significantly decreased in V5 ≤ 60% group. When the MLD was ≤ 14 Gy, the ≥ 1 grade acute RP was significantly decreased in the V5 ≤ 60% group. When the MLD was >14 Gy, the ≥ grade 2 acute RP was significantly decreased in the V5 ≤ 60% group. CONCLUSIONS: The low dose volume of the lung is effective in predicting radiation pneumonitis in patients with esophageal cancer treated with 3D-CRT only. The comprehensive parameters combined with V5, V20 and MLD may increase the effect in predicting radiation pneumonitis.

Digital holographic microtomography for high-resolution refractive index mapping of live cells.

Quantification of three-dimensional (3D) refractive index (RI) with sub-cellular resolution is achieved by digital holographic microtomography (DHµT) using quantitative phase images measured at multiple illumination angles. The DHµT system achieves sensitive and fast phase measurements based on iterative phase extraction algorithm and asynchronous phase shifting interferometry without any phase monitoring or active control mechanism. A reconstruction algorithm, optical diffraction tomography with projection on convex sets and total variation minimization, is implemented to substantially reduce the number of angular scattered fields needed for reconstruction without sacrificing the accuracy and quality of the reconstructed 3D RI distribution. Tomogram of a living CA9-22 cell is presented to demonstrate the performance of the method. Further, a statistical analysis of the average RI of the nucleoli, the nucleus excluding the nucleoli and the cytoplasm of twenty CA9-22 cells is performed.

HIF-1α contributes to hypoxia-induced invasion and metastasis of esophageal carcinoma via inhibiting E-cadherin and promoting MMP-2 expression.

Hypoxia-inducible factor-1α (HIF-1α) has been found to enhance tumor invasion and metastasis, but no study has reported its action in esophageal carcinoma. The goal of this study was to explore the probable mechanism of HIF-1α in the invasion and metastasis of esophageal carcinoma Eca109 cells in vitro and in vivo. mRNA and protein expression of HIF-1α, E-cadherin and matrix metalloproteinase-2 (MMP-2) under hypoxia were detected by RT-PCR and Western blotting. The effects of silencing HIF-1α on E-cadherin, MMP-2 mRNA and protein expression under hypoxia or normoxia were detected by RT-PCR and Western blotting, respectively. The invasive ability of Eca109 cells was tested using a transwell chambers. We established an Eca109-implanted tumor model and observed tumor growth and lymph node metastasis. The expression of HIF-1α, E-cadherin and MMP-2 in xenograft tumors was detected by Western blotting. After exposure to hypoxia, HIF-1α protein was up-regulated, both mRNA and protein levels of E-cadherin were down-regulated and MMP-2 was up-regulated, while HIF-1α mRNA showed no significant change. SiRNA could block HIF-1α effectively, increase E-cadherin expression and inhibit MMP-2 expression. The number of invading cells decreased after HIF-1α was silenced. Meanwhile, the tumor volume was much smaller, and the metastatic rate of lymph nodes and the positive rate were lower in vivo. Our observations suggest that HIF-1α inhibition might be an effective strategy to weaken invasion and metastasis in the esophageal carcinoma Eca109 cell line.

[Prognostic analysis of clinicopathological factors in patients after radical resection of esophageal carcinoma].

OBJECTIVE: To explore factors affecting the survival in patients after radical resection of esophageal carcinoma, and to provide a valuable reference for selecting treatment protocol after surgery. METHODS: Clinicopathological data of 618 esophageal cancer patients who underwent radical resection at the Fourth Hospital of Hebei Medical University from May 2002 to June 2006 were collected and reviewed in this study. All patients had no cancer history, did not receive preoperative radiotherapy or chemotherapy, and had Karnofsky performance scores ≥ 70. Univariate analysis was performed by using log-rank test to determine predictors of survival, and multivariable analysis was performed by a Cox regression model. RESULTS: The overall 1-, 3-, 5-year survival rates were 83.32%, 53.33%, 36.02%, respectively, and the median survival time was 38.33 months. The Cox regression analysis showed that operation mode, intraoperative findings of the extent of tumor invasion, pathological T stage, and the number of metastatic lymph nodes were significant predictors of survival. For patients with lymph node metastasis, the overall 1-, 3-, and 5-year survival rates did not significantly differ between the operation alone group and the postoperative prophylactic radiotherapy group. For patients without lymph node metastasis, the 1-, 3-, and 5-year survival rates were 94.34%, 51.55%, and 34.41%, respectively, in the postoperative radiotherapy group, significantly higher than those in the operation alone group (63.08%, 23.30% and 4.36%; χ(2) = 15.99, P < 0.01). CONCLUSIONS: The independent prognostic factors of esophageal cancer patients after radical resection include the operation mode, intra-operative findings of the extent of tumor invasion, pathological T stage, the number of lymph node metastasis and the number of regions of lymph node metastasis. Postoperative prophylactic radiotherapy is beneficial for esophageal cancer patients with lymph node metastasis.

Dosimetric and clinical predictors of radiation-induced lung toxicity in esophageal carcinoma.

AIMS AND BACKGROUND: Radiation-induced lung toxicity occurs frequently in patients with esophageal carcinoma. This study aims to evaluate the clinical and three-dimensional dosimetric parameters associated with lung toxicity after radiotherapy for esophageal carcinoma. METHODS AND STUDY DESIGN: The records of 56 patients treated for esophageal carcinoma were reviewed. The Radiation Therapy Oncology Group criteria for grading of lung toxicity were followed. Spearman's correlation test, the chi-square test and logistic regression analyses were used for statistical analysis. RESULTS: Ten of the 56 patients developed acute toxicity. The toxicity grades were grade 2 in 7 patients and grade 3 in 3 patients; none of the patients developed grade 4 or worse toxicity. One case of toxicity occurred during radiotherapy and 9 occurred 2 weeks to 3 months after radiotherapy. The median time was 2.0 months after radiotherapy. Fourteen patients developed late irradiated lung injury, 3 after 3.5 months, 7 after 9 months, and 4 after 14 months. Radiographic imaging demonstrated patchy consolidation (n = 5), atelectasis with parenchymal distortion (n = 6), and solid consolidation (n = 3). For acute toxicity, the irradiated esophageal volume, number of fields, and most dosimetric parameters were predictive. For late toxicity, chemotherapy combined with radiotherapy and other dosimetric parameters were predictive. No obvious association between the occurrence of acute and late injury was observed. CONCLUSIONS: The percent of lung tissue receiving at least 25 Gy (V25), the number of fields, and the irradiated length of the esophagus can be used as predictors of the risk of acute toxicity. Lungs V30, as well as chemotherapy combined with radiotherapy, are predictive of late lung injury.

[Short hairpin RNA-mediated MDC1 gene silencing enhances the radiosensitivity of esophageal squamous cell carcinoma cell line ECA109].

OBJECTIVE: To explore the effect of MDC1 gene silencing by RNA interference on the radiosensitivity of human esophageal carcinoma cell line ECA109. METHODS: The vectors containing short hairpin RNA (shRNA) targeting MDC1 gene (pMDC1-shRNA) were cotransfected with pPACKH1-lentivector packaging system into 293T cells to package the lentivirus particles. Forty-eight hours after the transfection with specific or control lentiviral vectors, the stable integrants were selected using copGFP reporter gene; real-time RT-PCR and Western blotting were used to detect the expression levels of MDC1 mRNA and protein in the transfected ECA109 cells, respectively. The cell cycle distribution was measured with flow cytometry at 12, 24 and 48 h after a 5 Gy irradiation, and the radiosensitivity of esophageal carcinoma cell was evaluated by clone formation array. RESULTS: Sequence analysis confirmed correct insertion of MDC1-shRNA construct into pSIH1-H1-copGFP. The percentage of G2/M phase ECA109/ MDC1 cells was lower than that of ECA109 and ECA109/negative cells. The value of D0, SF2 and Dq of ECA109/ MDC1 cells were 1.88 Gy, 0.84 and 1.20, respectively, lower than those of ECA109 cells (3.06 Gy, 0.91 and 1.59) and those of ECA109/negative cells (2.90 Gy, 0.89 and 1.47). CONCLUSION: RNA interference can inhibit MDC1 gene expression and enhance the radiosensitivity of ECA109 cells in vitro.

[Effect on retardation of G2/M phase in esophageal carcinoma cells transfected with CHK1 and CHK2 shRNA after irradiation].

OBJECTIVE: To observe the effect of RNA interference on CHK1 and CHK2 expression and change of G2/M phase arrest in esophageal carcinoma cells after irradiation. METHODS: Four sequences short hairhip RNA (shRNA) of each CHK1 and CHK2 genes were constructed and connected with vector of pENTR/U6 plasmid, respectively, and then transfected into Eca109 cells with lipofectamine 2000 reagent. Protein and mRNA expression of CHK1 and CHK2 genes were detected with Western blotting and RT-PCR, respectively. Cell cycling was measured by flow cytometry after 5 Gy irradiation. Cell survival rate after 5 Gy irradiation was evaluated by clonegenetic assay. RESULTS: Four shRNA vector each of CHK1 and CHK2 genes were successfully constructed and transfected into Ecal09 cells, respectively. Protein expression of CHK1 and CHK2 were obviously decreased. Their mRNA expressions were also decreased after transfected with shRNA of CHK1 and CHK2. Arrest of G2/M stage in Eca109 cells were obviously decreased only in cells transfected with CHK1 shRNA but not with CHK2 shRNA at 12 h after 5 Gy irradiation. In first progeny Eca109 cells transfected with CHK1 and CHK2 shRNA, expression of CHK1 and CHK2 protein was also decreased. The level of phosphorylated CHK2-T68 expression was decreased at 1 h after 5 Gy irradiation, and at 72 h only transfected with CHK2 shRNA but not with CHK1 shRNA. Phosphorylation level of CHK1-S345 was not increased after transfected with CHK1 or CHK2 shRNA, but arrest of G2/M stage still remained at 12 h after 5 Gy irradiation and at 72 h accordingly. The cell survival rate was decreased in Eca109 cells transfected with CHK1 or CHK2 shRNA after 5 Gy irradiation. CONCLUSION: After transfected with shRNA of CHK1 or CHK2, their expressions of mRNA and protein in Ecal09 cells are markedly inhibited and this inhibition effect can be observed in their first progeny cells and at least hold for 3 days. Arrest of G2/M phase can be reduced after irradiation when teansfected with shRNA of CHK1 and the radiosensitivity of Ec109 cells can be increased.