Troponin T1 silencing inhibits paclitaxel resistance and the development of breast cancer via suppressing rat sarcoma virus/rapidly accelerated fibrosarcoma 1 pathway

OBJECTIVE

We aimed to determine the role of Troponin T1 (TNNT1) in paclitaxel (PTX) resistance and tumor progression in breast cancer (BC).

METHODS

Differentially expressed genes were obtained from the GSE4298 and GSE90564 datasets. Hub genes were isolated from protein-protein interaction networks and further validated by real-time quantitative polymerase chain reaction. The effect of TNNT1 on PTX resistance was determined using cell counting kit-8, 5-ethynyl-2'-deoxyuridine, wound healing, transwell, flow cytometry assays, and subcutaneous xenografted tumor model. Western blotting was used to detect proteins associated with PTX resistance, apoptosis, migration, invasion, and other key pathways. Hematoxylin-eosin and immunohistochemical staining were used to evaluate the role of TNNT1 in tumors.

RESULTS

After comprehensive bioinformatic analysis, we identified CCND1, IGF1, SFN, INHBA, TNNT1, and TNFSF11 as hub genes for PTX resistance in BC. TNNT1 plays a key role in BC and is upregulated in PTX-resistant BC cells. TNNT1 silencing inhibited PTX resistance, proliferation, migration, and invasion while promoting apoptosis of PTX-resistant BC cells. Tumor xenograft experiments revealed that TNNT1 silencing suppresses PTX resistance and tumor development in vivo. In addition, TNNT1 silencing inhibited the expression of proteins in the rat sarcoma virus (RAS)/rapidly accelerated fibrosarcoma1 (RAF1) pathway in vivo. Treatment with a RAS/RAF1 pathway activator reversed the inhibitory effect of TNNT1 silencing on proliferation, migration, and invasion while promoting apoptosis of PTX resistance BC cells.

CONCLUSION

Silencing of TNNT1 suppresses PTX resistance and BC progression by inhibiting the RAS/RAF1 pathway, which is a promising biomarker and therapeutic target for drug resistance in BC.

A generalized l 2,p-norm regression based feature selection algorithm

Feature selection is an important data dimension reduction method, and it has been used widely in applications involving high-dimensional data such as genetic data analysis and image processing. In order to achieve robust feature selection, the latest works apply the l 2 , 1 or l 2 , p -norm of matrix to the loss function and regularization terms in regression, and have achieved encouraging results. However, these existing works rigidly set the matrix norms used in the loss function and the regularization terms to the same l 2 , 1 or l 2 , p -norm, which limit their applications. In addition, the algorithms for solutions they present either have high computational complexity and are not suitable for large data sets, or cannot provide satisfying performance due to the approximate calculation. To address these problems, we present a generalized l 2 , p -norm regression based feature selection ( l 2 , p -RFS) method based on a new optimization criterion. The criterion extends the optimization criterion of ( l 2 , p -RFS) when the loss function and the regularization terms in regression use different matrix norms. We cast the new optimization criterion in a regression framework without regularization. In this framework, the new optimization criterion can be solved using an iterative re-weighted least squares (IRLS) procedure in which the least squares problem can be solved efficiently by using the least square QR decomposition (LSQR) algorithm. We have conducted extensive experiments to evaluate the proposed algorithm on various well-known data sets of both gene expression and image data sets, and compare it with other related feature selection methods.

[SHOX2 promotes migration, invasion and stemness of bladder cancer cells in vitro]

OBJECTIVE

To explore the role of human short stature homeobox 2 (SHOX2) in regulating the migration, invasion and stemness of human bladder cancer cells.

METHODS

We analyzed SHOX2 gene expression in bladder cancer and adjacent tissues based on TCGA database. Univariate survival analysis of SHOX2 gene expression in TCGA-BLCA data was performed using GEPIA. The probable function of SHOX2 was predicted using GSEA. Human bladder cancer T24 cell models of SHOX2 knockdown or overexpression were assessed for changes in migration and invasion abilities using wound healing assay and Transwell assay, and their cancer stem cell-like characteristics were evaluated using tumorsphere formation assay and colony formation assay. Western blotting was used to detect the expressions of epithelial mesenchymal transition (EMT) markers Ecadherin and vimentin and the TGF-β signaling network component TβR-I in the cells.

RESULTS

SHOX2 expression was significantly higher in bladder cancer tissues than in the adjacent tissues (P < 0.05), especially in paired tissue specimens (P < 0.01), and was negatively correlated with the overall survival of the patients (P < 0.05). SHOX2 gene expression was correlated positively with EMT-related (P < 0.05) and stemness-related gene signatures (P < 0.01). In T24 cells, SHOX2 knockdown significantly suppressed cell migration and invasion, which was significantly enhanced by SHOX2 overexpression (P < 0.01). The cancer stem cell-like characteristics of T24 cells was repressed by SHOX2 knockdown but significantly enhanced by SHOX2 overexpression (P < 0.01). SHOX2 knockdown induced morphological changes of the cells into epithelioid cells, whereas SHOX2 overexpression induced a mesenchymal morphology of the cells. SHOX2 knockdown increased E-cadherin expression and decreased vimentin and TβR-I expression, while SHOX2 overexpression increased the expressions of vimentin and TβR-I in the cells.

CONCLUSION

SHOX2 promotes the migration, invasion and stemness of human bladder cancer cells possibly by regulating EMT via the TGF-β signaling pathway.

Correlation between family history and characteristics of breast cancer

Family history is a major risk factor for breast cancer; approximately 5–10% cases of breast cancer are associated with a family history. Herein, we investigated the link between family history and breast cancer features to elucidate the importance of family history in the diagnosis and treatment of breast cancer. Data from 10,549 patients with breast cancer were collected from 2014 to 2017. Detailed information about the family history of the patients including the degree and number of relatives affected and the types of cancer was recorded. The tumors were pathologically and clinically classified based on the stage, grade, ER, PR, HER2, Ki-67 status, and subtypes, according to standard guidelines. Data were analyzed using χ² test and multiple logistic regression. Patients with a family history of other cancer types were significantly older at diagnosis than patients with a family history of breast/ovarian cancer (p = 0.002) and those without a family history of cancer (p < 0.001). Patients without a family history of cancer were typically diagnosed at a later stage, including high frequency in N2 (p = 0.035) and TNM stage III (p = 0.015). Compared with patients with second-/third-degree relatives, those with first-degree relatives having breast/ovarian cancer had a higher median age (54.1, p < 0.001) at diagnosis and showed more advanced disease. No significant difference was found between ER, PR, and HER2 status in patients with and without a family history of cancer. Family history of breast cancer can influence the cancer characteristics of the patients at diagnosis, especially patient age, tumor stage, and grade.

Decreased Expression of TIM-3 on Th17 Cells Associated with Ophthalmopathy in Patients with Graves' Disease

Purpose:

Thyroid-associated Ophthalmopathy (TAO) is one of the most common orbital immunological diseases in adults. CD4+ helper T (Th) cells play important roles in the pathogenesis of TAO. But the mechanisms regulating CD4+ T cell activity is unclear. This study examines T cell immunoglobulin domain and mucin domain 3 (TIM-3) expression in helper T cell type 1 (Th1), Th17, and regulatory T cells in sufferers of TAO.

Methods:

Participants were divided into 3 groups: patients with TAO, patients with Graves’ disease but without orbitopathy (GD), and healthy control patients (HC). Peripheral blood samples were collected for each patient in the designated group. Flow cytometry methods assessed the frequency of Th1 (CD4+IFN-γ+), Th17 (CD4+IL-17+), regulatory T cells (CD4+CD25hiCD127lo), and TIM-3 protein expression. Mean fluorescence intensity (MFI) measured the magnitude of TIM-3 expression and the percentage of TIM-3+ cells for each patient.

Results:

Compared to the GD group, TAO patients possessed higher frequencies of Th1 and Th17 cells in peripheral blood samples. The percentage of TIM-3+ Th1 and Th17 cells was significantly lower in the TAO patients than the GD group. Across all patients sampled, TIM-3+ cell percentage negatively correlated with Th1 cell frequency. Th1 and Th17 cells exhibited significantly decreased expression of TIM-3 in TAO patients compared to healthy controls. Regulatory T cells showed little TIM-3 expression and we observed no significant differences in frequency between groups.

Conclusion:

These results suggest a role for TIM-3 in the regulation of Th1 and Th17 cells and the pathogenesis of Graves’ ophthalmopathy.

Correlation of radiotherapy with prognosis of elderly patients with hormone receptor-positive breast cancer according to immunohistochemical subtyping

Objective

The present study examined the effect of radiotherapy on recurrence and survival in elderly patients with hormone receptor-positive early breast cancer.

Methods

A retrospective analysis of 327 patients aged ≥65 years, with stage I−II, hormone receptor-positive breast cancer who underwent breast-conserving surgery and received endocrine therapy (ET) or radiotherapy plus endocrine therapy (ET+RT) was performed. Both groups were divided into luminal A type and luminal B type subgroups. Evaluation criteria were 5-year disease-free survival (DFS), local relapse rate (LRR), overall survival (OS), and distant metastasis rate (DMR).

Results

There were significant differences in 5-year DFS [hazard ratio (HR)=1.59, 95% confidence interval (95% CI), 1.15−2.19; P=0.005] and LRR (HR=3.33, 95% CI, 1.51−7.34; P=0.003), whereas there were no significant differences in OS and DMR between ET group and ET+RT group. In luminal A type, there was no significant difference in 5-year DFS, LRR, OS and DMR between ET group and ET+RT group. In luminal B type, there were statistically significant differences in 5-year DFS (HR=2.19, 95% CI, 1.37−3.49; P=0.001), LRR (HR=5.45, 95% CI, 1.65−17.98; P=0.005), and OS (HR=1.75, 95% CI, 1.01−3.05; P=0.048) between ET group and ET+RT group. In the ET group, there were significant differences between luminal A type and luminal B type in 5-year DFS (HR=1.84, 95% CI, 1.23−2.75; P=0.003) and OS (HR=1.76, 95% CI, 1.07−2.91; P=0.026).

Conclusions

After breast-conserving surgery, radiotherapy can reduce the LRR and improve the DFS and OS of luminal B type elderly patients, whereas luminal A type elderly patients do not benefit from radiotherapy. Without radiotherapy, luminal A type patients have better DFS and OS than luminal B type patients.

Modelling invasive group A streptococcal disease using bioluminescence

BACKGROUND

The development of vaccines and evaluation of novel treatment strategies for invasive group A streptococcal (iGAS) disease requires suitable models of human infection that can be monitored longitudinally and are preferably non-invasive. Bio-photonic imaging provides an opportunity to reduce use of animals in infection modelling and refine the information that can be obtained, however the range of bioluminescent GAS strains available is limited. In this study we set out to develop bioluminescent iGAS strains for use in in vivo pneumonia and soft tissue disease models.

RESULTS

Using clinical emm1, emm3, and emm89 GAS strains that were transformed with constructs carrying the luxABCDE operon, growth and bioluminescence of transformed strains were characterised in vitro and in vivo. Emm3 and emm89 strains expressed detectable bioluminescence when transformed with a replicating plasmid and light production correlated with viable bacterial counts in vitro, however plasmid instability precluded use in the absence of antimicrobial pressure. Emm89 GAS transformed with an integrating construct demonstrated stable bioluminescence that was maintained in the absence of antibiotics. Bioluminescence of the emm89 strain correlated with viable bacterial counts both in vitro and immediately following infection in vivo. Although bioluminescence conferred a detectable fitness burden to the emm89 strain during soft tissue infection in vivo, it did not prevent dissemination to distant tissues.

CONCLUSION

Development of stably bioluminescent GAS for use in vitro and in vivo models of infection should facilitate development of novel therapeutics and vaccines while also increasing our understanding of infection progression and transmission routes.

Quality of meta-analyses in major leading orthopedics journals: A systematic review

BACKGROUND

Meta-Analyses are the basis of professional and healthcare agencies recommendations and have a growing importance. Quality of meta-analyses has been investigated in some medical fields but to our best knowledge this issue remains under investigated in orthopedics. Therefore, we performed a systematic analysis to: 1) after the introduction of PRISMA statement as a comprehensive guideline and the use of the AMSTAR tool as the standard for sufficient review methodology, has the quality of MAs improved because of that? 2) have some general characteristics influenced the quality of MAs (country, funding source, number of authors)?

MATERIAL AND METHODS

We systematically searched the meta-analyses in the top four journals with the impact factor (2015) as following: JBJS, Osteoarthritis Cartilage Arthroscopy and Clin Orthop Relat Res from 2005 to 2008 and from 2012 to 2015. Likewise from 2012-2015, we also analyzed the meta-analyses from OTSR. Characteristics were extracted based on the PRISMA statement and the AMSTAR tool. Country, number of authors, funding source were also extracted.

RESULTS

A total of 154 meta-analyses were included in the present study. Score with PRISMA statement and the AMSTAR checklist were 20.86±3.04 out of a maximum of 27 and 7.86±1.55 out of a maximum of 11. The best journal was OTSR according to the PRISMA (23.06±1.92) and AMSTAR (9.13±0.87) scores. And the worst journal was Clin Orthop Relat Res according to the PRISMA score (19.4±2.70) and JBJS according to the AMSTAR score (6.78±1.65). Twelve items showed significant difference in the PRISMA statement, and five items in the AMSTAR checklist. Integral score of PRISMA statement and AMSTAR checklist has a significant difference between 2005-2008 and 2012-2015. The MAs reported from U.S. (56, 36.4%) were more than any other region in the world. And the MAs published by Asia/Oceania increased remarkably between these two period times [from (4, 10.8%) to (45, 38.5%)].

CONCLUSION

This study showed that methodological reporting quality of meta-analyses in the major orthopedics journals has improved after the publication of the PRISMA statement.

LEVEL OF EVIDENCE

Level III.

Geographical and ethnic distribution of MTHFR gene polymorphisms and their associations with diseases among Chinese population

Numerous studies have investigated the distribution of methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms and their associations with diseases in China. In this study we conducted a systematic review and meta-analysis of these studies (715 eligible studies in total).Results revealed that the frequencies of the MTHFR C677T and A1298C polymorphisms varied markedly in different areas and ethnicities, and even showed geographical gradients. The MTHFR C677T polymorphism was significantly associated with 42 clinical disorders (p < 0.05), mostly relating to the diseases of circulatory system, birth defects and cancers. The association of the A1298C polymorphism with three diseases (coronary heart disease, breast cancer and neural tube defects fathers) was statistically significant (p < 0.05). However, according to the Venice criteria, only the associations of the C677T polymorphism with breast and ovarian cancers were assessed as having strong epidemiological credibility. This is the first study to provide a comprehensive assessment of the current status and gaps in genetic epidemiological study of the two polymorphisms in China, and its findings may be useful for medical and public health practices. Future studies are warranted to focus on the interactions of MTHFR genes with environmental exposure and with other genes, and to improve their methodological quality and reporting of findings.

Orthopedics research output from China, USA, UK, Japan, Germany and France: A 10-year survey of the literature

BACKGROUND

In the past decade, researchers have made great progress in the field of Orthopedics. However, the research status of different countries is unclear. To summarize the number of published articles, we assessed the cumulative impact factors in top orthopedic journals. The aims of the study were to measure: 1) the quality and quantity of publications in orthopedics-related journals from China and other five counties, 2) the trend of the number of publications in orthopedics-related journals.

METHODS

The related journals were selected based on the 2014 scientific citation index (SCI) and articles were searched based on the PubMed database. To assess the quantity and quality of research output, the number of publications including clinical trials, randomized controlled trials, meta-analyses, case reports, reviews, citations, impact factors, number of articles in the top 10 journals and most popular journals were recorded.

RESULTS

A total of 143,138 orthopedics articles were published from 2005 to 2014. The USA accounts for 24.9% (35,763/143,138) of the publications, followed by UK (7878/143,138 (5.5%)), Japan (7133/143,138 (5.0%)), Germany (5942/143,138 (4.2%)), China (4143/143,138 (2.9%)) and France (2748/143,138 (1.9%)). The ranking for accumulated impact factors as follows: USA, UK, Japan, Germany, France and China. The mean impact factor's order is USA, China, Germany, Japan, France, UK, and interestingly the mean impact factors in Japan is similar to the Germany in 2005-2014. The USA had the highest percentage of articles in the top 10 journals, while China owns the least. The USA had the highest number of average citations, while Japan had lowest number of average citations.

CONCLUSIONS

According to this study, we can conclude that the USA has had been leading the orthopedics research in the past 10 years. Although China still falls behind, it has made considerable progress in the orthopedics research, not only in quantity but also quality.

LEVEL OF EVIDENCE

IV.

Final overall survival results from a randomised, phase III study of erlotinib versus chemotherapy as first-line treatment of EGFR mutation-positive advanced non-small-cell lung cancer (OPTIMAL, CTONG-0802)

BACKGROUND

The OPTIMAL study was the first study to compare efficacy and tolerability of the epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI) erlotinib, versus standard chemotherapy in first-line treatment of patients with EGFR mutation-positive advanced non-small-cell lung cancer (NSCLC). Findings from final overall survival (OS) analysis and assessment of post-study treatment impact are presented.

PATIENTS AND METHODS

Of 165 randomised patients, 82 received erlotinib and 72 gemcitabine plus carboplatin. Final OS analyses were conducted when 70% of deaths had occurred in the intent-to-treat population. Subgroup OS was analysed by Cox proportional hazards model and included randomisation stratification factors and post-study treatments.

RESULTS

Median OS was similar between the erlotinib (22.8 months) and chemotherapy (27.2 months) arms with no significant between-group differences in the overall population [hazard ratio (HR), 1.19; 95% confidence interval (CI) 0.83-1.71; P = 0.2663], the exon 19 deletion subpopulation (HR, 1.52; 95% CI 0.91-2.52; P = 0.1037) or the exon 21 L858 mutation subpopulation (HR, 0.92; 95% CI 0.55-1.54; P = 0.7392). More patients in the erlotinib arm versus the chemotherapy arm did not receive any post-study treatment (36.6% versus 22.2%). Patients who received sequential combination of EGFR-TKI and chemotherapy had significantly improved OS compared with those who received EGFR-TKI or chemotherapy only (29.7 versus 20.7 or 11.2 months, respectively; P < 0.0001). OS was significantly shorter in patients who did not receive post-study treatments compared with those who received subsequent treatments in both arms.

CONCLUSION

The significant OS benefit observed in patients treated with EGFR-TKI emphasises its contribution to improving survival of EGFR mutant NSCLC patients, suggesting that erlotinib should be considered standard first-line treatment of EGFR mutant patients and EGFR-TKI treatment following first-line therapy also brings significant benefits to those patients.

CLINICALTRIALSGOV IDENTIFIER

NCT00874419.

Knee osteoarthritis and all-cause mortality: the Wuchuan Osteoarthritis Study

BACKGROUND

Previous studies showed that knee osteoarthritis (OA) is associated with increased mortality in Caucasians. While prevalence of knee OA is higher in Chinese than in Caucasians, no study has examined whether knee OA increases mortality in Chinese population.

METHODS

Between 8/2005-10/2005 1025 residents aged ≥50 years were recruited in randomly selected rural communities in Wuchuan, China. Subjects completed a home interview and had weight-bearing posteroanterior semiflexed view of radiographs at tibiofemoral joints and skyline view of radiographs at patellofemoral joints, and were followed until end of 2013. A knee was defined as having radiographic osteoarthritis (ROA) if either Kellgren/Lawrence (KL) score at tibiofemoral joint ≥2 or presence of OA at patellofemoral joint based on OARSI criteria. Symptomatic knee osteoarthritis (SxOA) was defined if both pain (i.e., knee pain occurred on most days in past month) and ROA were present at the same knee. We examined the relation of knee SxOA and knee ROA to the all-cause mortality, respectively, using Cox-proportional hazard models adjusting for potential confounders.

RESULTS

Over the follow-up period 99 subjects died. The mortality rates were 32.6 (95% confidence interval (CI): 19.6-54.0) and 10.9 (95% CI: 8.8-13.5) per 1000 person-years among subjects with and without SxOA, respectively. Multivariable adjusted hazard ratio of all-cause mortality for knee SxOA was 1.9 (95% CI: 1.0-3.5). However, no such association was observed for knee ROA (hazard ratio = 1.2, 95% CI: 0.7-1.9).

CONCLUSIONS

Knee SxOA was associated with an increased risk of all-cause mortality among the residents in the rural areas of China.

Basic fibroblast growth factor promotes macaque follicle development in vitro

Fertility preservation is an important type of frontier scientific research in the field of reproductive health. The culture of ovarian cortices to i) initiate primordial follicle growth and ii) procure developing follicles for later oocyte maturation is a promising fertility preservation strategy, especially for older women or cancer patients. At present, this goal remains largely unsubstantiated in primates because of the difficulty in attaining relatively large follicles via ovarian cortex culture. To overcome this hurdle, we cultured macaque monkey ovarian cortices with FSH, kit ligand (KL), basic fibroblast growth factor (bFGF), and/or epidermal growth factor (EGF). The various factors and factor combinations promoted primordial follicle development to different extents. Notably, both bFF (bFGF, 100 ng/ml and FSH, 50 ng/ml) and KF (KL, 100 ng/ml and FSH, 50 ng/ml) contributed to the activation of primordial follicles at day 12 (D12) of culture, whereas at D18, the proportions of developing follicles were significantly higher in the bFF and KF groups relative to the other treatment groups, particularly in the bFF group. Estradiol and progesterone production were also highest in the bFF group, and primary follicle diameters were the largest. Up until D24, the bFF group still exhibited the highest proportion of developing follicles. In conclusion, the bFGF–FSH combination promotes nonhuman primate primordial follicle developmentin vitro, with the optimal experimental window within 18 days. These results provide evidence for the future success of human ovarian cortex culture and the eventual acquisition of mature human follicles or oocytes for fertility restoration.

Quality of life (QoL) analyses from OPTIMAL (CTONG-0802), a phase III, randomised, open-label study of first-line erlotinib versus chemotherapy in patients with advanced EGFR mutation-positive non-small-cell lung cancer (NSCLC)

BACKGROUND

The OPTIMAL study found that erlotinib improved progression-free survival (PFS) versus standard chemotherapy in Chinese patients with advanced EGFR mutation-positive non-small-cell lung cancer (NSCLC). This report describes the quality of life (QoL) and updated PFS analyses from this study.

PATIENTS AND METHODS

Chinese patients ≥ 18 years with histologically confirmed stage IIIB or IV NSCLC and a confirmed activating mutation of EGFR (exon 19 deletion or exon 21 L858R point mutation) received erlotinib (150 mg/day; n = 82) or gemcitabine-carboplatin (n = 72). The primary efficacy end point was PFS; QoL was assessed using the Functional Assessment of Cancer Therapy-Lung (FACT-L) questionnaire, Trial Outcome Index (TOI) and Lung Cancer Subscale (LCS).

RESULTS

Patients receiving erlotinib experienced clinically relevant improvements in QoL compared with the chemotherapy group in total FACT-L, TOI and LCS (P < 0.0001 for all scales). Erlotinib scored better than chemotherapy for all FACT-L subscales from baseline to cycles 2 and 4 (non-significant). In the updated analysis, PFS was significantly longer for erlotinib than chemotherapy (median PFS 13.7 versus 4.6 months; HR = 0.164, 95% CI = 0.105-0.256; P < 0.0001), which was similar to the previously reported primary analysis.

CONCLUSION

Erlotinib improves QoL compared with standard chemotherapy in the first-line treatment of patients with EGFR mutation-positive advanced NSCLC.

Sustained moderate visual loss as a predictive end point for visual loss in non-proliferative diabetic retinopathy

PURPOSE

In PKC-DRS2, the efficacy of the oral PKC-beta inhibitor, ruboxistaurin 32 mg/day, was measured by the primary end point of sustained moderate visual loss (SMVL: a > or = 15 letter decrease from baseline on the ETDRS (Early Treatment Diabetic Retinopathy Study) chart sustained at least for the last 6 months of study participation). We now evaluate whether SMVL is more accurate than moderate visual loss (MVL: a single occurrence of a decrease from baseline of > or = 15 ETDRS letters) for predicting future visual loss.

METHODS

Study eyes with moderately severe to very-severe non-proliferative diabetic retinopathy, best-corrected visual acuity of at least 45 letters on the ETDRS chart (approximately Snellen 20/125), and no prior pan retinal photocoagulation were evaluated in 506 patients (869 eyes) who completed 36 months of treatment.

RESULTS

Sixty-five percentage (26/40) of study eyes with the onset of SMVL within 24 months of enrolment still had SMVL at study completion (36 months). In comparison, only 24% (30/126) with MVL within 24 months had SMVL at study completion. Analyses based on data from 6, 12, and 18 months of treatment were similar.

CONCLUSIONS

SMVL is a more predictable measure of subsequent visual loss than is a single time point measure of MVL.

Overexpression of von Hippel-Lindau tumor suppressor protein and antisense HIF-1alpha eradicates gliomas

The von Hippel-Lindau tumor suppressor protein (pVHL) suppresses tumor formation by binding the alpha subunits of hypoxia-inducible-factors responsible for stimulating tumor angiogenesis and glycolysis, and targeting them for ubiquitination and proteasomal destruction. Loss of pVHL leads to tumorigenesis and development of sporadic renal cell carcinomas and central nervous system hemangioblastomas. In the present study, we investigated whether engineered overexpression of pVHL in C6 glioma cells, which already express endogenous pVHL, would suppress the tumorigenicity of this particular tumor cell type. C6 cells overexpressing VHL displayed a reduced growth rate (70% inhibition) compared to the parental cell line when subcutaneously implanted in athymic (nu/nu) mice. Growth inhibition was associated with a 50% reduction in the number of tumor vessels and a 60% increase in tumor cell apoptosis, due in part to downregulation of HIF-1, VEGF, and the antiapoptotic factor Bcl-2, respectively. Gene transfer of VHL suppressed the growth of established C6 gliomas, and synergized with antisense HIF-1 to completely eradicate tumors. The data suggest that VHL gene therapy and/or agents that increase VHL expression could have utility in the treatment of gliomas, particularly when combined with agents that inhibit the expression or function of HIF-1.

BRCA1 and BRCA2 sequence variants in Chinese breast cancer families

A series of 45 high-risk breast cancer patients, consisting of 25 affected individuals from 16 families in China with at least two cases of breast cancer and 20 cases of breast cancer diagnosed under age 35 without reported family history, were studied for germline mutations of the BRCA1 and BRCA2 genes. Thirteen of the 16 families contained at least one case diagnosed under age 50. Three distinct protein truncating sequence variants, likely to be disease-associated, were identified: two novel mutations in BRCA1 (1584G>T and 5028delC), and a previously reported mutation in BRCA2 (7883delTTAA). Additional sequence variants identified included common polymorphisms, and several variants of unknown clinical significance, including a novel BRCA1 alteration. Based on models for predictive testing using allele frequencies and risks estimated in Western populations, our results suggest that BRCA1/2 mutations account for a somewhat smaller fraction of breast cancer cases in Tianjin than in the Caucasian populations studied. This difference could be the result of a lower penetrance of BRCA1/2 mutations due to the surrounding environmental and hormonal milieu, or a lower frequency of mutations in this population. Larger, more detailed, studies will be necessary to determine which factors underlie this difference.

Tissue-specific regulatory elements in the human alcohol dehydrogenase 6 gene

The human alcohol dehydrogenase gene ADH6 is expressed at the highest levels in fetal and adult liver. We have mapped cis-acting elements that affect its expression. The sequence from bp -34 to -62 (site C) that includes the TATA box was strongly bound by nuclear proteins from liver, hepatoma cells, and fibroblasts. A truncation that removed the upstream part of site C but left the TATA homology intact dramatically reduced transcription; altering 5 bp in this region had much less effect. Part of site C can be bound by C/EBPalpha, but cotransfection with C/EBPalpha or C/EBPbeta did not stimulate transcription. The proximal region did not display tissue specificity, so we cloned the upstream region to search for additional regulatory sequences. The region between -1.6 and -2.3 kb stimulated transcription in hepatoma cells and inhibited it in fibroblasts. We identified two sites in this region that affect transcription independently of their orientation. Site 1 was a negative regulatory element in fibroblasts but had no effect in hepatoma cells. Site 2 was a positive regulatory element in hepatoma cells but had no effect in fibroblasts. This combination of positive and negative regulatory elements can play a significant role in the tissue-specific expression of ADH6.

[Inhibitory effect of paeonol on experimental atherosclerosis in quails]

OBJECTIVE

To study the effect of paeonol on experimental atherosclerosis in quails caused by high lipid feeding.

METHOD

The effects of oral administration of 300 and 600 mg/kg of paeonol on lipid levels in serum, hemorrheology and aortic intimal abnormalities were investigated.

RESULT

Paeonol decreased TC, TG, LDL, vLDL, APOB100 levels in serum and TC levels in aorta and liver. The ratios of HDL/TC, HDL2/HDL3, apoA1/apoB100 were elevated. In addition, the drug reduced the whole blood viscosity, Plasma viscosity and plasma fibrinogen, and inhibited erythrocyte aggregation.

CONCLUSION

Oral administration of paeonol can reduce the development of atherosclerosis.

[Surgical treatment of spinal dural arteriovenous fistulas]

OBJECTIVE

To discuss the operation modalities of spinal dural arteriovenous fistulae (SDAVFs) and treatment with anticoagulant agents after surgery.

METHOD

The medical records, radiographic studies and operations of 23 patients with SDAVFs were reviewed. Laminectomy was performed at the level of the arterialized venous entry into the subarachnoid space in 18 patients with thoracic and lumbar lever AVFs, followed by coagulation, clipping and division of the vein. In 14 of 18 patients, the arteriovenous nidus in the dura was identified and obliterated by coagulation. The draining veins were interrupted at L(5) - S(1) level in 5 patients with sacral AVFs. Anticoagulant treatment was given in 13 patients.

RESULT

Outcome was good in 20 patients and 2 of the 20 had transient postoperative neurological deterioration that reversed by anticoagulant agents. No changes were seen in 2 patients except one deteriorated.

CONCLUSION

Surgical interruption of arterialized radicular-medullary draining vein of SDAVFs provides lasting occlusion of the fistula, and postoperative anticoagulant therapy can prevent thrombosis of the coronal venous plexus.

[Pharmacological studies on Chinese bone extract granules]

The Chinese Bone Extract Granules could enhance the immunity of mice with spleen-deficiency, increase the serum calcium content of rats with bone loose, inhibit the gastrointestinal movement of mice with spleen-deficiency and improve the absorption of D-xylose in small intestine of rats with spleen-deficiency. The maximal tolerance dose for mice to take orally twice a day was greater than 50 g/kg. The subacute toxicologic test for 6 weeks of continuous feeding to rats did not show any obvious toxicity.