Interaction and Targeting Strategies of Colorectal Cancer Stem Cells and Tumor Microenvironment / 肿瘤防治研究

Colorectal cancer stem cells are undifferentiated tumorigenic cells with malignant phenotypic characteristics in colorectal cancer and considered as the main cause of tumor recurrence, drug resistance, and metastasis through self-renewal and differentiated cloning. Colorectal cancer stem cells and various components in the tumor microenvironment are interdependent and influence one another. The relationship between tumor stem cells and other components in the tumor microenvironment may play an important role in the treatment of colorectal cancer. This review summarizes this relationship.

Low-dose paclitaxel combined with thalidomide inhibits angiogenesis in mice bearing S180 sarcoma / 中国肿瘤临床

Objective: To investigate the effect of low-dose paclitaxel combined with thalidomide on angiogenesis in mice bearing S180 sarcoma. Methods: An S180 sarcoma-bearing mouse model was established. Forty tumor-bearing mice were randomly divided into four groups: A, the control group, administered normal saline; B, the paclitaxel group, administered 20 mg/kg paclitaxel by intraperitoneal injection three times per week for 2 weeks; C, the thalidomide group, administered 200 mg/kg thalidomide by gavage three times per week for 2 weeks; and D, the paclitaxel + thalidomide group, administered paclitaxel (20 mg/kg) and thalidomide (200 mg/kg) by intraperitoneal/intragastric administration three times per week for 2 weeks. Tumor weight, tumor inhibition rate, microvascular density (MVD), and vascular endothelial growth factor (VEGF) expression were measured. Results: Tumor weight, VEGF expression, and MVD were lower in groups B, C, and D (P<0.05) than in the control. VEGF expression and MVD were lower in group D than in groups B and C; these differences were statistically significant (P<0.05). Conclusions: Low-dose paclitaxel combined with thalidomide exerted an inhibitory effect on vascular growth in S180 sarcoma.

Rapid detection of novel avian influenza virus subtype H7N9 by multiplex real-time RT-PCR / 病毒学报

In order to develop a rapid detection kit for novel avian influenza virus (AIV) subtype H7N9, two sets of specific primers and probes were designed based on the nucleotide sequences of hemagglutinin antigen (HA) and neuraminidase antigen (NA) of novel H7N9 virus (2013) available in GenBank to establish the method of TaqMan probe-based multiplex real-time RT-PCR for rapid detection of AIV subtype H7N9. The primer and probe of HA were for all H7 subtype AIVs, while the primer and probe of NA were only for novel N9 subtype AIVs. The results showed that this method had high sensitivity and specificity. This method was applicable to the testing of positive standard sample with a minimum concentration of 10 copies/microL; it not only distinguished H7 subtype from H1, H3, H5, H6, and H9 subtypes, but also distinguished novel N9 subtype from traditional N9 subtype. A total of 2700 samples from Zhuhai, China were tested by this method, and the results were as expected. For the advantages of sensitivity and specificity, the method holds promise for wide application.

Inhibition of proliferation of H5N1 subtype AIV in CEF by chemosynthetic siRNA / 病毒学报

In order to study the proliferation inhibition effect of H5N1 subtype avian influenza virus (AIV) with small interfere RNA (siRNA), a total of 4 siRNAs were designed in accordance with the NP and PA genes of H5N1 subtype AIV, the siRNAs were then transfected to chicken embryo fibroblast(CEF), CEF was infected with H5N1 subtype AIV after 6 hrs. Virus titer of cell supernatant was tested at 16-56hrs post infection, and pathological changes of the cells was observed; mRNA levels of NP, PA, HA and p13-actin gene were tested at 36hrs post infection. The results showed that these 4 siRNAs could inhibit the prolif-eration of H5N1 subtype AIV in CEF in varying degrees, and one siRNA targeting PA was best per-formed. The experimental results also showed that the inhibition effect was decreased with the time prolonged. This research provides a basis for further studying RNAi on AIV prevention and control.

The clinical signifcance of expression of ERCC1 and PkCalpha in non-small cell lung cancer / 中国肺癌杂志

<p><b>BACKGROUND AND OBJECTIVE</b>Excision repair cross-complementing 1 (Excision-Repair Cross-Complementing 1, ERCC1), an important member of the DNA repair gene family, plays a key role in nucleotide excision repair and apoptosis of tumor cells. Protein kinase C-alpha (Protein kinase C, PKCalpha), an isozyme in protein kinase C family, is an important signaling molecule in signal transduction pathways of tumors, which has been implicated in malignant transformation and proliferation. The aim of this study was to explore the clinical significance of ERCC1 and PKCalpha in non-small cell lung cancer (NSCLC).</p><p><b>METHODS</b>The expression of ERCC1 and PKCalpha were examined by immunohistochemistry (IHC) in the specimens of 51 cases of NSCLC patients tissue and 21 cases of paracancerous tissue. The relationship between detected data and patients' clinical parameters was analyzed by SPSS 13.0 software.</p><p><b>RESULTS</b>The positive expression rate of ERCC1 and PKCalpha in NSCLC tissues was significantly higher than paracancerous tissues (P < 0.05). Expression of ERCC1 was closely related to clinical stage and N stage. The positive rate of ERCC1 was higher in III+IV or N1+N2 stage patients compared with I+II or N0 stage (P = 0.011, P = 0.015). We also found that 5-year survival of negative group of ERCC1 was remarkably higher than that of positive group by chi2 test (P < 0.05). Expression of ERCC1 was positively correlative to PKCalpha by Spearman's correlation analysis (r = 0.425, P = 0.002) in NSCLC.</p><p><b>CONCLUSION</b>The results suggest ERCC1 and PKCalpha might be correlated with the development of NSCLC. ERCC1 might be related to prognosis of NSCLC. There might be existed a mechanism of coordination or regulation between ERCC1 and PKCalpha.</p>