Changes in extracellular matrix in different stages of colorectal cancer and their effects on proliferation of cancer cells

BACKGROUND The extracellular matrix is the main component of the tumor microenvironment.Extracellular matrix remodels with the oncogenesis and development of tumors.Previous studies usually focused on the changes of proteins in normal colorectal tissues and colorectal cancers.Little is known about the changes in the extracellular matrix in different stages of colorectal cancer and the effects of these changes on the development of this cancer.AIM To test the changes of type I collagen,type IV collagen,matrix metalloproteinase-2(MMP-2),matrix metalloproteinase-9(MMP-9),and tissue inhibitor of metalloproteinase-3(TIMP-3)in different stages of colorectal cancer and the effects of these changes on the proliferation of cancer cells.METHODS The extracellular matrix from various stages of colorectal cancer and normal colon tissue was obtained by using acellular technology.We used proteomics to detect the differential expression of proteins between normal colon tissues and colorectal cancer tissues,and then we used Western blot to observe their expression in each stage of colorectal cancer and in normal colon tissue.By coculturing the extracellular matrix and HT29 colon cancer cells in vivo and in vitro,we tested the cancer cell proliferation rate in vitro by methyl thiazolyl tetrazolium(MTT)assay and in vivo by measuring the tumor volume.RESULTS The expression of type I collagen and MMP-2 increased with increased tumor stage.The expression of MMP-9 was higher in colorectal cancer tissues and was highest in stage III cancer.The expression of type IV collagen and TIMP-3 decreased with increased tumor stage.The proliferation rate of cancer cells in the extracellular matrix of colorectal cancer was higher than that in the extracellular matrix of the normal colon.CONCLUSION These data suggest that the extracellular matrix structure and composition become disorganized during the development of tumors,which is more conducive for the growth of cancer cells.

Older age at first birth is a risk factor for pancreatic cancer： a meta-analysis

BACKGROUND： Some studies found that age at first birth is associated with pancreatic cancer; others did not. The present meta-analysis was to evaluate the relationship between age at first birth and pancreatic cancer in women.DATA SOURCES： We searched Pub Med, Embase, and the Cochrane Library for relevant publications on age at first birth and pancreatic cancer up to April, 2014. The eligible studies（six cohorts and five case-controls） were independently selected by two authors. Pooled relative risk（RR） estimates and corresponding 95% confidence interval（95% CI） were calculated using the inverse-variance method.RESULTS： The pooled RR of pancreatic cancer risk for the highest versus lowest categories of age at first birth was 1.21（95% CI： 1.01-1.45, P=0.314, I^2=13.7%）. Consistent relationships were also observed within subgroup analyses stratified by study design, geographic region, and whether the studies included adjustment for cigarette smoking, diabetes, or all of the confounders. In this meta-analysis, no publication bias among studies was observed using Egger＇s test（P=0.383） or Begg＇s test（P=0.436）.CONCLUSION： Our findings suggest that older age at first birth is associated with an increased risk of pancreatic cancer in women and the exact functional mechanism needs further investigation.

Correlation of Betel Quid with Oral Cancer from 1998 to 2017： A Study Based on Bibliometric Analysis

Background： Betel quid chewing has been a major risk factor for oral cancer （OC） in southern China. This study aimed to analyze the scientific publications on the relationship between betel quid chewing and OC and construct a model to quantitatively and qualitatively evaluate pertinent publications from 1998 to 2017. Methods： The publications from 1998 to 2017 were retrieved from the Web of Science Core Collection database. Microsoft Excel, Thomson Data Analyzer, VOSviewer, and CiteSpace software were used to analyze the publication outcomes, journals, countries/regions, institutions, authors, research areas, and research frontiers. Results： A total of 788 publications on the relationship between betel quid chewing and OC published until October 25, 2017, were identified. The top 4 related journals were Journal of Oral Pathology Medicine, Oral Oncology, Plos One, and lnternational Journal of Cancer. The top five countries engaged in related research included China, India, the United States, the United Kingdom, and Malaysia. The corresponding disciplines, such as oncology, oral surgery, pathology, environmental and occupational health, and toxicology, were mainly concentrated in three disciplines. The subject ternas squamous cell carcinoma, OC, betel quid, expression, oral submucous fibrosis, India, and p53 ranked first among research hotspots. The burst terms squamous cell carcinoma, OC, betel quid, and expression ranked first in research frontiers. Conclusions： Research in this area emphasized hotspots such as squamous cell carcinoma, OC, oral submucosal fibrosis, betel quid, and tobacco. The annual number of publications steadily decreased from 1998 to 2017, with a lack of a systematic study from interdisciplinary perspectives, inadequate pertinent journals, limited regions with the practice of betel quid chewing, and insufficient participation of researchers, which indicate that as the prevalence of OC increases, particularly in China, research in this area warrants further expansion.

Gender-specific differences in associations between economic status and systolic blood pressure or diastolic blood pressure

Hypertension is a significant contributor to cardiovascular diseases.When controlled ineffectively,hypertension can lead to heart diseases and stroke,which together constitutes the leading causes of global premature death and disability.According to a national cross-sectional survey in China,the prevalence of hypertension among adults aged≥18 years was 23.2%in 2015.