The cytotoxic effect of extract of camellia ptilophyllachang(ECPC) and extract of camellia sinensis(ECS) onHeLa cell line, poorly differentiated nasopharyngealcarcinoma cell line(CNE2) and gastric cancer cell line(MGC...The cytotoxic effect of extract of camellia ptilophyllachang(ECPC) and extract of camellia sinensis(ECS) onHeLa cell line, poorly differentiated nasopharyngealcarcinoma cell line(CNE2) and gastric cancer cell line(MGC-803 ) in vitro was studied using MIT assay method.The results showed that ECPC and ECS possessed significantcytotoxic effect on above three cell lines. The anticancer testin mice showed that ECPC had marked inhibitory effectagainst Ehrlich solid carcinoma(ESC) with inhibition ratesof 17. 8 48. 3% and with inhibition rates of 28. 3-54. 5% against reticular cell sarcoma(L2), and that ECShad inhibition rates of 31 . 5 -49. 4 % against ESC and 35. 8- 50% against L2. These two extracts had only marginalinhibitory effect against sarcoma- 180. The unknottingactivity of DNA topoisomerase II was inhibited completelyby ECPC and ECS at the concentration of 50 μg/ mlsuggesting that DNA topoisomerase II might be a targetenzyme of these two extracts.展开更多
Several groups of parasitic protozoa, as represented by Giardia, Trichomonas, En-tamoeba and Microsporida, were once widely considered to be the most primitive extant eu-karyotic group―Archezoa. The main evidence for...Several groups of parasitic protozoa, as represented by Giardia, Trichomonas, En-tamoeba and Microsporida, were once widely considered to be the most primitive extant eu-karyotic group―Archezoa. The main evidence for this is their ‘lacking mitochondria’ and pos-sessing some other primitive features between prokaryotes and eukaryotes, and being basal to all eukaryotes with mitochondria in phylogenies inferred from many molecules. Some authors even proposed that these organisms diverged before the endosymbiotic origin of mitochondria within eukaryotes. This view was once considered to be very significant to the study of origin and evolution of eukaryotic cells (eukaryotes). However, in recent years this has been challenged by accumulating evidence from new studies. Here the sequences of DNA topoisomerase II in G. lamblia, T. vaginalis and E. histolytica were identified first by PCR and sequencing, then com-bining with the sequence data of the microsporidia Encephalitozoon cunicul and other eukaryotic groups of different evolutionary positions from GenBank, phylogenetic trees were constructed by various methods to investigate the evolutionary positions of these amitochondriate protozoa. Our results showed that since the characteristics of DNA topoisomerase II make it avoid the defect of ‘long-branch attraction’ appearing in the previous phylogenetic analyses, our trees can not only reflect effectively the relationship of different major eukaryotic groups, which is widely accepted, but also reveal phylogenetic positions for these amitochondriate protozoa, which is different from the previous phylogenetic trees. They are not the earliest-branching eukaryotes, but diverged after some mitochondriate organisms such as kinetoplastids and mycetozoan; they are not a united group but occupy different phylogenetic positions. Combining with the recent cytological findings of mitochondria-like organelles in them, we think that though some of them (e.g. diplo-monads, as represented by Giardia) may occupy a very low evo展开更多
Background Surrogate markers may be used to assess the response to neoadjuvant treatment. The association between HER2 overexpression and favorable response to specific therapy in breast cancer is controversial, and t...Background Surrogate markers may be used to assess the response to neoadjuvant treatment. The association between HER2 overexpression and favorable response to specific therapy in breast cancer is controversial, and the mechanism unclear. The purpose of the study was to evaluate HER2 and topoisomerase Ⅱα （Topo Ⅱα） as candidates for predicting the response to neoadjuvant chemotherapy in breast cancer patients.Methods Between 1999 and 2006, seventy-six breast cancer patients who had received neoadjuvant chemotherapy were studied. Regimens including either CEF （cyclophosphamide, epirubicin, 5-fluorouracil） or CMF （cyclophosphamide, methotrexate, 5-fluorouracil） were given in more than three cycles to this group of patients. Protein expression of HER2 and Topo Ⅱα were determined by immunohistochemistry. The primary endpoint was pathological and clinical response.Results Of 76 primary breast cancer samples, 27 （35.5%） showed overexpression of either HER2 （25%） or Topo Ⅱα protein （10.5%）, whereas in 7 tumors （9.2%） both proteins were found to be overexpressed. Ten patients （13.2%） had a clinical complete response and 21 （27.6%） had a clinical partial response. Five women （6.6%） had a pathological complete response, 5 （6.6%） had microscopic residual disease, and 46 （60.5%） had macroscopic residual disease. HER2 and Topo Ⅱα overexpression was significantly associated with a favorable response （P 〈0.001 and P=0.005 respectively）.Conclusion Our study suggests that HER2 and Topo Ⅱα overexpression could be predictors of the response to neoadjuvant chemothrapy in both the CEF and CMF arms.展开更多
文摘The cytotoxic effect of extract of camellia ptilophyllachang(ECPC) and extract of camellia sinensis(ECS) onHeLa cell line, poorly differentiated nasopharyngealcarcinoma cell line(CNE2) and gastric cancer cell line(MGC-803 ) in vitro was studied using MIT assay method.The results showed that ECPC and ECS possessed significantcytotoxic effect on above three cell lines. The anticancer testin mice showed that ECPC had marked inhibitory effectagainst Ehrlich solid carcinoma(ESC) with inhibition ratesof 17. 8 48. 3% and with inhibition rates of 28. 3-54. 5% against reticular cell sarcoma(L2), and that ECShad inhibition rates of 31 . 5 -49. 4 % against ESC and 35. 8- 50% against L2. These two extracts had only marginalinhibitory effect against sarcoma- 180. The unknottingactivity of DNA topoisomerase II was inhibited completelyby ECPC and ECS at the concentration of 50 μg/ mlsuggesting that DNA topoisomerase II might be a targetenzyme of these two extracts.
基金This work was supported by the Important Direction of Knowledge Innovation Program from Chinese Academy of Sciences(Grant No.KSCX2-SW-101C)National Natural Science Foundat ion of China(Grant Nos.90408016,30021004&30170135)Yunnan Province(Grant No.2000YP19).
文摘Several groups of parasitic protozoa, as represented by Giardia, Trichomonas, En-tamoeba and Microsporida, were once widely considered to be the most primitive extant eu-karyotic group―Archezoa. The main evidence for this is their ‘lacking mitochondria’ and pos-sessing some other primitive features between prokaryotes and eukaryotes, and being basal to all eukaryotes with mitochondria in phylogenies inferred from many molecules. Some authors even proposed that these organisms diverged before the endosymbiotic origin of mitochondria within eukaryotes. This view was once considered to be very significant to the study of origin and evolution of eukaryotic cells (eukaryotes). However, in recent years this has been challenged by accumulating evidence from new studies. Here the sequences of DNA topoisomerase II in G. lamblia, T. vaginalis and E. histolytica were identified first by PCR and sequencing, then com-bining with the sequence data of the microsporidia Encephalitozoon cunicul and other eukaryotic groups of different evolutionary positions from GenBank, phylogenetic trees were constructed by various methods to investigate the evolutionary positions of these amitochondriate protozoa. Our results showed that since the characteristics of DNA topoisomerase II make it avoid the defect of ‘long-branch attraction’ appearing in the previous phylogenetic analyses, our trees can not only reflect effectively the relationship of different major eukaryotic groups, which is widely accepted, but also reveal phylogenetic positions for these amitochondriate protozoa, which is different from the previous phylogenetic trees. They are not the earliest-branching eukaryotes, but diverged after some mitochondriate organisms such as kinetoplastids and mycetozoan; they are not a united group but occupy different phylogenetic positions. Combining with the recent cytological findings of mitochondria-like organelles in them, we think that though some of them (e.g. diplo-monads, as represented by Giardia) may occupy a very low evo
文摘Background Surrogate markers may be used to assess the response to neoadjuvant treatment. The association between HER2 overexpression and favorable response to specific therapy in breast cancer is controversial, and the mechanism unclear. The purpose of the study was to evaluate HER2 and topoisomerase Ⅱα （Topo Ⅱα） as candidates for predicting the response to neoadjuvant chemotherapy in breast cancer patients.Methods Between 1999 and 2006, seventy-six breast cancer patients who had received neoadjuvant chemotherapy were studied. Regimens including either CEF （cyclophosphamide, epirubicin, 5-fluorouracil） or CMF （cyclophosphamide, methotrexate, 5-fluorouracil） were given in more than three cycles to this group of patients. Protein expression of HER2 and Topo Ⅱα were determined by immunohistochemistry. The primary endpoint was pathological and clinical response.Results Of 76 primary breast cancer samples, 27 （35.5%） showed overexpression of either HER2 （25%） or Topo Ⅱα protein （10.5%）, whereas in 7 tumors （9.2%） both proteins were found to be overexpressed. Ten patients （13.2%） had a clinical complete response and 21 （27.6%） had a clinical partial response. Five women （6.6%） had a pathological complete response, 5 （6.6%） had microscopic residual disease, and 46 （60.5%） had macroscopic residual disease. HER2 and Topo Ⅱα overexpression was significantly associated with a favorable response （P 〈0.001 and P=0.005 respectively）.Conclusion Our study suggests that HER2 and Topo Ⅱα overexpression could be predictors of the response to neoadjuvant chemothrapy in both the CEF and CMF arms.
