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Objective: To analyze immunophenotypes and gene mutations of colorectal precancerous lesions and adenocarcinoma, and to compare the difference of carcinogenetic mechanisms between the two precancerous lesions., Methods: Fifty-three cases of colorectal serrated lesions including 30 hyperplastic polyps, 20 sessile serrated adenomas (SSA) and 3 mixed polyps were collected from January 2006 to June 2012.Forty-five cases of traditional adenomas and 50 cases of colorectal adenocarcinomas were also recruited. Thirty hyperplastic polyps, 20 cases of SSA, 3 mixed polyps and 45 traditional adenomas were investigated by immunohistochemistry for the expression of DNA mismatch repair (MMR) proteins (MLH1, MSH2 and MSH6) and DNA methyltransferase MGMT. Mutations of KRAS, BRAF and PIK3CA genes in 10 cases of SSAs, 10 traditional adenomas, 1 mixed polyps and 50 colorectal adenocarcinomas were analyzed by PCR followed by direct Sanger sequencing., Results: (1) Only 3 cases of hyperplastic polyps lost MLH1 expression, and none of SSAs or traditional adenomas showed loss of MLH1. The negative expression rates of MSH2, MSH6 and MGMT in hyperplastic polyps and SSA were significantly higher than those of traditional adenomas. (2) KRAS mutation was found in 5/10 cases of SSAs, 5/10 traditional adenomas and 1/1 mixed polyps. (3) Colorectal adenocarcinomas harbored the mutations of KRAS (48%, 24/50), BRAF (6%, 3/50) and PIK3CA (4%, 2/50)., Conclusions: Immunophenotypic and gene mutation profiles are different between colorectal serrated lesion and traditional adenoma. Alterations of MMR and MGMT expression play important roles in the pathogenesis of "serrated neoplasm". KRAS mutation is a significant genetic change in the early phase of colorectal carcinogenesis.

Objective: To investigate the change of aberrant methylation of p16, CDH, RASSF1A and TIMP3 in cervical carcinoma and their significance in cervical carcinoma., Methods: Using the bisulfite-modification technique and methylation-specific PCR (MSP), we examined the aberrant promoter hypermethylation patterns of 4 tumor suppressor genes (p16, CDH1, RASSF1A, TIMP3) in 140 samples of cervical intraepithelial neoplasia (CINI, n = 40), CINII-III (n = 40), cervical carcinomas (CC, n = 40), and normal cervical tissue as a control group (n = 20)., Results: (1) Methylation was completely absent in control tissues. (2) Significant differences between CINII-III group and CINI group were detected for p16 and CDH1 (22% vs 2%, P < 0.05; 35% vs 5%, P < 0.05), while there were no significant differences between the two groups for RASSF1A and TIMP3 (12% vs 2%, P > 0.05; 15% vs 2%, P > 0.05). (3) The presence of methylation of p16 (40%), CDH1 (58%), RASSF1A (20%) and TIMP3 (35%) in CC were higher than the corresponding CINII-III group, but with no significant differences (P > 0.05). (4) Significant differences between CC and CINIfor p16, CDH1, RASSF1A and TIMP3 genes (P < 0.05) were observed. (5) Methylation for at least one gene was a frequent event. These figures in CC 90% (36/40) were significantly different from CINII-III 55% (22/40; P < 0.05). In comparison between CINI8% (3/40) and CC and CINII-III, these figures were significantly different (P < 0.05)., Conclusions: Among the four genes, p16, CDH, RASSF1A and TIMP3, there is a significant trend for increased methylation with increasing degree of histopathological change. It suggests that the aberrant methylation of tumor suppressor genes plays a role during cervical cancer development. This may help identify women at increased risk for or cancer development and progression.

Background & Objective: Mitochondria play a key role in cell apoptosis, and apoptosis-inducing factor (AIF) is a kind of apoptotic protein located in mitochondria. The research on mitochondrial protein can be helpful for elucidating the role of mitochondria in apoptosis. This study was to clone and express recombinant human Delta1-120 AIF and validate its biological activities of binding DNA and inducing nuclear apoptosis., Methods: A human AIF gene fragment of 1515 bp(mitochondrial localization sequence was deleted) was amplified from SMMC-7721 cells by reverse transcription-polymerase chain reaction (RT-PCR) and cloned into pET32a(+) vector to construct recombinant plasmid pET32a-AIF. The recombinant plasmid was transfected into E.coli BL2l (DE3). AIF expression was induced by isoprophylthio-beta-D-galactoside (IPTG), and detected by SDS-PAGE and Western blot. AIF protein was purified by Ni afinity chromatography and then renatured. The biological activity of renatured AIF protein was detected by electrophoretic mobility shift assay (EMSA) and Hoechst staining., Results: The 1.5 kb AIF gene was successfully isolated, and cloned into pET32a(+) vector. Plasmid pAIF was identified by restrictive enzyme analysis and sequencing. Recombinant E.coli. strains expressing AIF were obtained. AIF protein amounted to 11% of the total bacterial protein when induced with IPTG at 37 degrees Celsius for 4 h. AIF was specially recognizing by anti-AIF and anti-his antibody. The purity of purified protein reached over 95%. After renaturation, AIF protein binded DNA and induced nuclear apoptosis., Conclusion: AIF protein with high purity and biological activity was obtained by the method described above.

Background & Objective: Detection of circulating tumor markers is one of current hot spots in tumor research. Free tumor DNA may exist in the peripheral blood of malignant tumor patients. Identical DNA mutations existing in both peripheral serum and primary tumor are found in many kinds of malignant tumors. This study used adenomatous polyposis coli (APC) gene promoter hypermethylation as a tumor marker to investigate the correlations of free tumor DNA to primary tumor and clinicopathologic features of breast cancer., Methods: The methylation status of APC gene in tumor tissue, paracancer normal tissue, and paired peripheral serum from 84 patients with breast cancer and 10 patients with benign breast diseases were detected by methylation-specific polymerase chain reaction (MSP)., Results: The detection rate of APC gene promoter hypermethylation was 45.2% in tumor tissues and 31.0% in paired peripheral sera. APC gene hypermethylation in peripheral serum was significantly correlated to that in tumor tissue (r=0.977, P=0.002). The sensitivity of detecting APC gene hypermethylation in peripheral serum was 68.4%; the specificity was 97.8%. The aberrant methylation of APC gene in tumor tissue and peripheral serum had no correlation to patients' age, tumor stage, tumor size, histological type, and receptor status (P>0.05). No aberrant methylation of APC gene was found in the serum samples from healthy control and the patients without gene methylation in tumor tissue., Conclusion: The aberrant tumor gene methylation in peripheral serum of breast cancer patients is significantly correlated to that in primary tumor.

To study the effect of sudan I, III and IV on the growth of HepG-2 and SGC-7901, the ratio of DNA/RNA and 3D image in HepG-2 treated by different dose of sudan I, III and IV was detected by LCM, the content change of DNA and the cell cycle in SGC-7901 treated by different dose of sudan I, III and IV was detected by flow cytometry. Results showed the ratio of DNA/RNA in control group was 1.2232 +/- 0.0844, after treated by sudan I , III and IV the fluorescence intensity of DNA was stronger than RNA, and the low dose group was very marked compared with control group (p < 0.01), the ratio was 1.609 6 +/- 0.1990, 1.4455 +/- 0.1633,and 1.7081 +/- 0.1090. 3D image showed that the DNA fluorescence mostly assembles on nucleolus, which was denser and stronger than RNA. Sudan I, III and IV accelerated the cell cycle from G1 phase to S and G2 phase, the average content of DNA in G1 phase decreased and in S and G2 phase increased, the index of PI and SPF increased. Sudan I, III and IV could affect cell cycle and advanced its differentiation and proliferation.

Objective: To investigate the difference in methylation of genomic DNA between gastric primary cancer and lymph nodes with metastatic gastric cancer., Methods: Methylation CpG island amplification (MCA) was used to enrich the methylated DNA sequences in the cancer tissues and lymph nodes with metastatic gastric cancer resected during operation from 5 patients. Representational difference analysis (RDA) was conducted with the MCA products from the lymph nodes with metastatic gastric cancer as testers and the MCA products of the gastric primary cancer as drivers. The differentially methylated DNA fragments were cloned and sequenced, and underwent similarity analysis by BLAST system. The relationship between the clone sequence and related gene was analyzed by GenBank. Hybridization analysis was performed, using the No 1-3 round RDA products and the MCA products of the tissues of gastric primary cancer and lymph nodes with metastatic gastric cancer with digoxin-labeled KL22 fragment as probe., Results: Nineteen differentially methylated DNA sequences were obtained, distributed at the 5'-end, exon, intron, and 3'-end. KL59 fragment was located in the 9q21, the first exon of p16 gene. KL12 fragment was located in the promoter region of phosphotyrosine phosphatase receptor G (PTPRG) gene. Hybridization signals were obtained for all No 1-3 round RDA products and all testers, but not for the drivers., Conclusion: There is a difference in DNA methylation between the tissues of primary cancer and lymph nodes with metastatic gastric cancer. MCA-RNA is an effective method to study the gene methylation. PTPRG gene may be a candidate gene for metastasis of gastric cancer.

Objective: To investigate the role of STK15 in regulating mitosis of gastric cancer cells (MKN45) by gene silencing through RNA interference mechanism., Methods: RNA interference technique was used to inhibit STK15 expression in MKN45 cells. The expression levels of STK15 mRNA and protein were measured by real-time quantitative RT-PCR and Western blot respectively and cell morphological changes were investigated by reverse microscopy. In addition, cell cycle distribution and cellular proliferation were determined by flow-cytometry and MTT assay respectively. Finally, the mitotic phenotype of MKN45 cells was studied by immunofluorescence staining and confocal microscopy., Results: Silencing of STK15 gene by RNA interference was confirmed by marked decrease of STK15 mRNA and protein levels in the treated MKN45 cells. This silencing correlated with rounding of the cells, decreasing of DNA content in G(2) phase (P < 0.05) and a lowered proliferation index (P < 0.05), along with alterations of mitotic phenotype of MKN45 (P < 0.05)., Conclusion: STK15 gene may play a key role in regulating cellular mitosis and its inhibition by RNA interference leading to mitosis arrest in MKN45 cells.

Objective: To inquire into the mechanism of CDP (a purified component of Chinese crude drug) in inhibiting the breast cancer T47D cell growth., Methods: T47D cells were treated with different concentration of 5-azacytidine (5-aza-CR) and CDP for several days. The growth rate was assessed by cell proliferation experiment (MTT colorimetric assay). The changes in apoptic peak and cell cycle distribution were detected by flow cytometry (FCM). The levels of methylation and unmethylation status of p16 were detected by methylation specific PCR (MSP)., Results: After treatment with the two drugs, the cell growth rate decreased in a dose and time dependent manner (P<0.05). The cell cycle was influenced by the well-chosen concentration of 5-aza-CR (2 micromol/L) and CDP (50 micromol/L): the cell number increased from 65.1% to 71.3%, 84.3% in G0/G1 phase and decreased from 19.4% to 14.3%, 7.2% in S phase. Demethylation on p16 gene occurred after treatment with any of the two drugs for 6 days., Conclusion: CDP can reverse p16 hypermethylation and may hence inhibit the proliferation of tumor cells.

Background & Objective: The p53 codon 72 polymorphism affects human papillomavirus (HPV) E6-mediated degradation of p53. This study was to investigate distribution of p53 polymorphism in Guangdong women, and relationship between p53 polymorphism and tumorigenesis of cervical cancer., Methods: Cervical smears of 46 patients with cervical cancer (case group), and 84 patients with benign gynecologic tumor (control group) treated in our hospital from Sept. 2002 to May 2003 were collected. DNA, extracted from cervical smears,were examined by polymerase chain reaction (PCR) for detection of HPV DNA and p53 codon 72 polymorphism., Results: Positive rate of HPV DNA in case group was 47.8%, in control group was 20.2%. Proportions of genotypes Arg/Arg, Pro/Pro, and Arg/Pro in case group were 56.5%, 21.7%,and 21.7%, respectively; in control group were 71.4%,20.2%, and 8.3%,respectively. There were no significant differences in proportions of Arg/Arg (OR,0.520; 95% CI,0.245-1.102), and Arg/Pro (OR, 1.095; 95% CI,0.454-2.639) between 2 groups; proportion of Pro/Pro in case group was significantly higher than control group (OR, 3.056; 95% CI,1.076-8.678), but no significant difference was found in women with HPV infection., Conclusion: Arg/Arg genotype is not a high-risk factor for cervical cancer in Chinese population, and individuals with Pro/Pro genotype are likely to develop cervical cancer.

Background & Objective: Transcription factors of human cancer cells can regulate the expression of many malignancy-related gene products,relate to poor differentiation,and high metastasis of cancer cells,and also inhibit apoptosis of cancer cells. This study was designed to investigate the nuclear factor-kappa B (NF-kappaB)DNA binding activity in human astrocytoma tissue,and its significance with human astrocytoma development., Methods: The NF-kappaB DNA binding activities of 12 cases of normal brain tissue, and 37 cases of human astrocytoma tissue were detected by electrophoretic mobility shift assay (EMSA), and photo densitometry., Results: The absorbency of NF-kappaB DNA binding activity in human astrocytoma tissue was 134.2+/-24.1, higher than that in normal brain tissue (97.5+/-1.9)(P< 0.05). The NF-kappaB DNA binding activity in multiform glioblastoma tissue was highest (106.8+/-7.4), that in anaplasia Astrocytoma was 123.2+/-10.1, in astroblastoma was 139.3+/-16.8,and in astrocytoma was 160.2+/-18.6 (P< 0.05)., Conclusion: The NF-kappaB DNA binding activity correlates with malignancy degree of human astrocytoma.

Objectives: To investigate the differences in morphology, immunohistochemistry, DNA ploidy status, LOH and MSI of 11q13 and 1p between benign and malignant pheochromocytomas, and to find the marker or markers useful in distinction between benign and malignant pheochromocytoma or for predicting the malignant potential of this tumor., Methods: Twenty-two cases of clinically documented benign and malignant pheochromocytomas from the files of Peking Union Medical College Hospital were analyzed. Aside from histological study, Ki-67, p53, CgA, S-100, PCNA and survivin immunohistochemistry studies were performed. DNA ploidy status was assessed by flow cytometry on cell suspensions prepared from formalin-fixed, paraffin-embedded sections. Twelve tumors (7 benign and 5 malignant) with paired normal tissues were microdissected. Tumor and normal tissue DNA were extracted. The obtained DNAs and 8 microsatellite markers related to 11q13 and 1q were subjected to PCR amplification for analysis of LOH and MSI., Results: None of the tumors showed atypical mitosis, only 1 malignant tumor had a mitotic count > 1/10 HPF (2.3/10 HPF). Two malignant tumors exhibited confluent necrosis. Ki-67 index was low in benign tumors (average 0.73%), and high in malignant tumors (average 2.4%). The difference of Ki-67 index between benign and malignant tumors was statistically significant. DNA ploidy status did not correlate with malignancy. Although LOH and/or MSI of 11q13 and 1p were observed in several tumors, a statistically significant difference could not be reached due to the small number of tumors analyzed., Conclusion: Only Ki-67 index (> 3%) is an useful marker for distinguishing benign from malignant or for predicting the malignant potential of pheochromocytoma.

Background & Objective: DNA methylation status regulates gene expression and is associated with oncogenesis. Demethylation of DNA has been proposed as a possible new strategy for cancer prophylaxis and treatment. S-adenosylmethionine is required as methyl donor for both arsenic metabolism and DNA methylation. The present study was designed to explore the possibility and mechanism of re-expression of the silenced p16 gene in human myeloma cell line U266 cells by arsenic trioxide (As2O3)., Methods: The U266 cell line in which the p16 gene is silenced due to hypermethylation was treated with different concentration of As2O3. The PCR technique combined with HpaII and its isoschizomer MspI was used to assess p16 gene methylation status. The mRNA expression levels of p16 and DNA methyltransferases (DNMTs) genes were determined with RT-PCR technique. Western blot was performed for P16 protein expression analysis., Results: (1)The characteristic hypermethylation with losing expression of p16 gene in U266 cells was confirmed. After agarose gel electrophoresis, the genomic DNA digested with MspI showed a "smear" pattern, however the HpaII digested DNA showed a strong single band. There was no PCR amplified product of p16 gene when MspI digested DNA was used as the templates, whereas a 340 bp p16 gene product was found in HpaII digested DNA sample as the undigested DNA was amplified. Also, neither p16 mRNA nor P16 protein was detectable when assessed with RT-PCR and Western blot, respectively. (2)When the genomic DNA from cells treated with (0.5-2.0) micromol/L As2O3 was digested with HpaII and then analyzed by electrophoresis, a "smear" pattern was observed. The 340 bp product could not be amplified if such digested DNA was used as PCR templates. Detectable expression of both p16 mRNA and P16 protein was found in the cells treated with 1.0 micromol/L and 2.0 micromol/L As2O3. (3)Expression levels of DNMT 3A and 3B mRNA were increased in the treated cells and were dependent on As2O3 concentration, however no significant difference was found between each two groups (P >0.05)., Conclusion: As2O3 could induce p16 gene re-expression in human myeloma cell line U266 through DNA demethylation.

Objective: To screen the differentially methylated DNA sequences between mucosa adjacent to colorectal cancer (MACC) and normal colonic mucosa., Methods: The methylated DNA sequences were enriched by methylation CpG islands amplification (MCA), and the differentially methylated DNA sequences between MACC and normal colonic mucosa were isolated by representational difference analysis (RDA). Similarities between the separated fragments and the human genomic DNA were analyzed with BLAST program system in GenBank. With the separated fragment 1A12 as probe, dot blot was used to study its distribution between RDA products (No. 1-4 rounds), MACC (tester) and normal colonic mucosa(driver)., Results: Twenty-five differentially methylated DNA sequences were obtained. Preliminary studies indicated that 1A01 fragment was concerned with two different genes (LOC256866 and CECR7), it was located in the first exon of CECR7. 1A12 fragment was located in 5 flanking region of GR6 gene. By dot blot with 1A12 probe, hybridized signals were detected in MCA product of MACC and RDA products of No. 1-4 rounds, respectively. No signal was detected in MCA product of normal colonic mucosa., Conclusion: The differentially methylated DNA sequences can be isolated effectively between two different tissues with MCA coupled with RDA. Different methylated DNA fragments exist between MACC and normal colonic mucosa and these fragments may be concerned with colorectal cancer.

Objective: To research whether the antisense oligodeoxynucleotide (ASODN) of RNA component of human telomerase (hTR) can increase the susceptibility of K562 cells to cisplatin., Methods: K562 cells were treated with phosphorothoate ASODN complementary to the template region of hTR in vivo. The changing of telomerase activity was assayed by TRAP-PCR-ELISA and apoptosis by DNA gel electrophoresis, Annexin V, flow cytometry., Results: There was a marked decrease in telomerase activity in ASODN treated cells as compared with that in control and sense oligodeoxynucleotide (SODN)-treated cells; but no difference between the latter two groups. Agarose gel electrophoresis of genomic DNA from K562 cells treated with ASODN and cisplatin combination for 72 h showed typical DNA ladder; neither did DNA ladder from K562 cells treated with SODN plus cisplatin nor cisplatin alone. Apoptosis rates of K562 cells treated with ASODN for 24 h and then with cisplatin for 72 h were significantly increased. There were statistically significant difference in the percentage of apoptotic cells between hTR ASODN plus cisplatin and SODN plus cisplatin or cisplatin alone group., Conclusion: ASODN complementary to the template region of hTR can significantly suppress the telomerase activity and enhance cisplatin-induced apoptosis of K562 cells in vivo.

Background & Objective: Ras-MAPK signal transduction has been thought to play an important role in the carcinogenesis of chronic myelogenous leukemia. In this study, the authors investigated the effects and mechanism of mitogen-activated protein kinase (MAPK) in cell signal transduction of chronic myelogenous leukemia(CML)., Methods: After MAPK antisense oligodeoxynucleotide (ASO) was introduced into K562 cell line by liposomal transfection, the effects of ASO on K562 cell were evaluated by cell proliferation, DNA synthesis, MAPK protein content and MAPK activity., Results: The cell proliferation, DNA synthesis, MAPK protein content and MAPK activity were significantly inhibited by MAPK ASO, the inhibitory rates were 51.8%, 57.1%, 45.3%, and 61.6%, respectively,with significant difference in comparison to the control (P<0.05)., Conclusion: MAPK plays an important role in the signal transduction of CML and MAPK may become a new target in the treatment of CML.

Objective: To study the imprinting status and expression level of insulin-like growth factor 2 (IGF2) gene in colorectal cancer and to provide a clue for the mechanism of carcinogenesis of colorectal cancer., Methods: The expression levels of IGF2 in the paired colorectal cancer and adjacent normal tissue were examined and compared by use of semi-quantitative reverse transcription-polymerase chain reaction. The imprinting status of IGF2 was detected by restriction fragment length polymorphism. The relationships between the expression level of IGF2, its imprinting status, and the carcinogenesis of colorectal cancer were analyzed., Results: IGF2 was overexpressed in 82.4% (28/34) of colorectal cancer tissues which was significantly higher than those of the matched normal tissues (P<0.01, t=3.01). 87.5% (14/16) of colorectal cancer showed loss of imprinting(LOI), while 71.4%(10/14) of normal tissues also displayed LOI of IGF2., Conclusion: Overexpression of IGF2 was found to play an important role in carcinogenesis of colorectal cancer. LOI of IGF2 may be a prophase manifestation of colorectal cancer.

Gastric cancer, like all cancers, is considered to result in part from the accumulation of multiple genetic alterations leading to oncogene overexpression and tumour suppressor loss. More recently, the role of epigenetic change as a distinct and crucial mechanism to silence a variety of methylated tissue-specific and imprinted genes has emerged in many cancer types. The study of DNA methylation changes in gastric cancer has now provided additional clues into the pathogenesis of the disease. E-cadherin as a metastases suppressor is mutationally inactivated in both familial and sporadic forms of gastric cancers. Evidence now suggests that the transcriptional silencing of E-cadherin gene by promotor methylation plays a crucial role in the development and progression of gastric malignancies. In order to further analyze the role of E-cadherin gene promotor methylation in gastric carcinogenesis and progression, we performed the studies of promoter methylation status and protein expression of E-cadherin gene in associated progression stages of gastric cancer. DNA were extracted from the paraffin embedded gastric specimens of dysplasia(23 cases), early cancer (20 cases) and advanced cancer (20 cases). Methylation specific PCR and immunohistochemistry were used to analyze the promoter methylation status and the protein expression level of E-cadherin gene. Our results showed that E-cadherin promoter methylation occurred in all stages of gastric precancerous lesion and carcinogenesis, which suggests E-cadherin promotor methylation is an important event during gastric carcinogenesis and progression. The positive rate of E-cadherin promotor methylation in dysplasia, early gastric cancer and advanced gastric cancer was 78.3%, 80% and 90% respectively. There were significant differences between experimental groups and control group(30%), P < 0.05, but no significant differences among experimental groups, P > 0.05. All of advanced gastric cancer examined were completely E-cadherin protein-negative by immunohistochemistry. Fourteen of 20 early gastric cancer were E-cadherin-negative. And 23 dysplasia were all E-cadherin-positive. Thirty-one of 34(91%) of the E-cadherin-negative tumours had promotor methylation. This result indicated the downregulation expression of E-cadherin was associated with promotor methylation in early and advanced gastric cancer (P < 0.01).

Objective: To probe the possible mechanism of growth-inhibitory and apoptosis of oral squamous cell carcinoma by arsenic trioxide., Methods: The induction of apoptosis in two tongue squamous carcinoma cells treated by arsenic trioxide was investigated. The morphology changes of the cells was observed under electron microscope. The mitochondrial transmembrane potential was detected using rhodamine 123 and flow cytometry. The cell cycle was detected by flow cytometry, and p16, p53, BCL-2, Caspase-3, and PARP changes were examined by western blot., Results: 1. The antiproliferative effect on the oral squamous carcinoma cells by arsenic trioxide was carried out through two ways: induction of apoptosis and toxicity damage. 2. Activation of the caspase-3 and PARP, while no changes of p16, p53, BCL-2 occurred. 3. Mitochondrial transmembrane potential collapse and G(2)-M stagnation were correlated with apoptosis of oral squamous cell carcinoma., Conclusions: 1. Tubulins and mitochondria may be the chief action position of arsenic trioxide, which is the start-up factors of mechanism. 2. Activation of the caspase-3 proteolytic pathway may be one of the pivotal ways of apoptosis procedure induced by arsenic trioxide.

Objective: To analyze the relationship between DNA content and biological behavior and its prognostic significance in non-small cell lung cancer., Methods: Tumor DNA content was determined by flow cytometry in the specimens from 58 patients with resected non-small cell lung cancer. The DNA content of each cell subpopulation was expressed as the DNA index (DI), and an internal standard was provided by the normal pulmonary parenchymal cells in the same specimen. The prognostic value of DNA content in non-small cell lung cancer was assessed by Cox's model analysis., Results: In qualitative analysis, there was no relationship between DNA ploidy (diploidy or aneuploidy) and the following factors: tumor size, metastasis of lymph node, clinical stage, pathologic type, pathologic grade or survival. In quantitative analysis, high DNA index was observed in tumor size > 3 cm, metastasis of lymph node, stage III/IV, adenocarcinoma and shorter survival, which was statistically significant. Cox's model analysis showed that DNA index was a prognostic factor in non-small cell lung cancer and DNA index > 2.0 was an independent prognostic factor., Conclusion: DNA index analysis is useful for the evaluation of the biological behavior and the prognosis of non-small cell lung cancer.

Background & Objective: Histone deacetylation is associated with transcriptional activation controlled by DNA methylation. It is important to investigate changes of tumor cells treated with agent through two kinds of mechanisms. This study was designed to investigate the synergic effect of histone deacetylase inhibitor, sodium phenylbutyrate(SPB), and demethylating agent, 5-Aza-2'-deoxycytidine(5-Aza-CdR), on cell growth and explore the possibility of re-expression of the hypermethylated and silenced p16 gene in the myeloma cell line U266., Methods: The cell cycle was analyzed by flow cytometry. Apoptosis was observed by transmission electron microscopy, DNA ladder, fluorescence-activated cell sorter (FACS). The expression level of p16 was detected by RT-PCR and Western blot analysis., Results: The apoptotic rates of U266 cells induced by 5-Aza-CdR(1 mumol/L), SPB(1 mmol/L) alone and combination of 5-Aza-CdR and SPB were 15.09%, 89.19%, and 85.18%, respectively. The G1 phase was arrested and sub-G1 phase(50%) was induced by combination of 5-Aza-CdR and SPB. There was no G1 phase arrested when SPB or 5-Aza-CdR was used alone. The proportion of cells in G2 phase was increased with SPB alone. SPB was not able to induce the expression of p16. The expression level of p16 was induced with 5-Aza-CdR. The expression level of both mRNA and protein of p16 was increased significantly by synergy of SPB and 5-Aza-CdR., Conclusions: p16 gene in U266 cell line could be reactivated markedly with synergy of 5-Aza-CdR and SPB with cell cycle arresting in G1 phase. Meanwhile, the cell cycle phase occurring apoptosis that induced by combination of 5-Aza-CdR with SPB is different from that induced by each alone.

Background & Objective: It was recently reported that the proteins coded by CRKL (CT10 regulator of kinase like, CRK like) gene play an important role in the pathogenesis of chronic myeloid leukemia (CML). This study was designed to investigate the effect of antisense oligonucleotides of CRKL gene (CRKL-ASDON) on CML K562 cell lines., Methods: K562 cells were transfected with CRKL-ASDON, using liposome as the vector. The changes of cell morphology, cell cycle, and gene expression were observed through living cell count, transmission electron microscopy, flow cytometry (FCM), DNA Ladder assay., Results: Under the action of CRKL-ASDON, growth of K562 cell was markedly inhibited. An apoptotic peak appeared before diploid peak in FCM; various apoptotic stages of K562 cells were observed under electron microscope; over ladder-shaped band of cell apoptosis was seen in abstracted DNA of the gene group by gel electrophoresis. Meanwhile, the above changes did not appear in the control., Conclusion: CRKL gene is an important factor in the pathogenesis of Ph-positive CML.

Background & Objective: The drug-resistance and metastasis in early stages of human malignant ovarian neoplasm have significant effect on chemotherapy of human ovarian carcinoma. The objective of this study was to explore the impact of arsenic trioxide(As2O3) on proliferation and metastasis of drug-resistant human epithelial ovarian carcinoma cell line 3AO/cDDP, in order to treat human ovarian carcinoma thoroughly., Methods: The growing inhibiting rates of drug-resistant human ovarian carcinoma cell line 3AO/cDDP by various concentrations of As2O3 in different time course were studied by methyl thiazolyl tetrazolium (MTT) method; Apoptosis percentage, cell cycle phase distribution and expressions of Fas, N-myc, nm23H1 and MTA1 gene were estimated by flow cytometry (FCM); 3AO/cDDP cells apoptosis phenotype was observed by transmissional electron microscopy., Results: 3AO/cDDP cell growing inhibiting rates by As2O3 were significantly different in dose-dependent and time-dependent manners(P < 0.05); Within a certain concentration range, 3AO/cDDP apoptosis inducing rates by As2O3 were dose- and time-dependent, and the most appropriate concentration was 3.0 mumol/L. Lower concentrations of As2O3 perturbed cell progressing through S/G2 phase, while higher concentrations selectively induced S phase cells apoptosis; As2O3 up-regulated Fas and nm23H1 gene expressions, but down-regulated N-myc and MTA1 gene expressions. Morphological observation indicated that As2O3 inducing 3AO/cDDP death characterized by apoptotic phenotype., Conclusion: As2O3 could influence the capacity of growth and proliferation of drug-resistant human ovarian carcinoma cell line and its mechanism could be positively and negatively related with Fas, nm23H1 gene and N-Myc, MTA1 gene expressions.

Background & Objective: The anticancer mechanism of boanmycin was thought to inhibit the synthesis of protein in human esophageal cancer cell line. But it is not clear that there are other mechanisms of boanmycin to produce its anticancer effect on human esophageal cancer. This study was designed to examine the effect of boanmycin on apoptosis and cell cycle of human esophageal cancer cells (Eca-109)., Methods: Microscopic observation, flow cytometry, and agarose gel electrophoresis were used to determine the induction of apoptosis and the changes of cell cycle., Results: The human esophageal cancer xenografts in nude mice treated by boanmycin showed morphological changes of different apoptotic phases. In vitro, boanmycin (50-125 micrograms/ml, 30-36 hours) elicited typical apoptotic changes in Eca-109 cells and typical DNA ladder of apoptotic cells appeared. The Eca-109 cells treated by boanmycin for 42 hours were blocked at G2/M phase., Conclusion: Boanmycin could induce apoptosis of Eca-109 cells and block the cell cycle at G2/M phase.

To establish a quantitative assay for telomerase activity and analyze the telomerase activity in peripheral blood mononuclear cells (PBMNC) from patients with acute leukemia, a fluorescent dye, PicoGreen, was added to the products after telomere repeat amplification protocol. The samples were excited at 480 nm and the fluorescence emission intensity was measured at 520 nm using a spectrofluorometer. Telomerase activity was detected in PBMNCs from 20 cases of normal individuals and 25 patients with acute leukemia. The results showed that the fluorescence of PicoGreen binding to double-stranded DNA specifically was enhanced with increase of DNA quantities. In conclusion, the met hod is rapid, simple and quantitative, the telomerase activities of PBMNCs from acute leukemia patients are significantly higher than that of the normal controls.

In order to explore the differences between the mechanisms of selenite-induced apoptosis and arsenic induced apoptosis in NB4 cells, growth inhibition was determined by MTT test, apoptosis determined by DNA electrophoresis and analysis of intracellular DNA contents, reactive oxygen species and reduced glutathione in the cell were measured by Lucigenin dependent chemoluminescent (CL) test and spectrophotometry, and mitochondrial transmembrane potential was measured by flow cytometry. The results showed that: 5 micro mol/L sodium selenite similar to 1 micro mol/L arsenic trioxide could induce the apoptosis of NB4 cells after treatment for 24 hours. Both could elevate the level of reactive oxygen species and intensify mitochondrial transmembrane potential collapse, accompanied with decrease of reduced glutathione centent. The effect of selenium selenite on these aspects was more significant than those of arsenic trioxide. Elevation of intracellular glutathione in N-acytlcysteine pretreated NB4 cells could enhance the selenite induced apoptosis and oxidative stress, but ameliorate the arsenic trioxide induced apoptosis and oxidative stress. It was concluded that sodium selenite and arsenic trioxide can induce the apoptosis of NB4 cells, but there are significant differences between the mechanisms of selenite-induced and arsenic-induced apoptosis in NB4 cells, particularly in the influence of intracellular glutathione content on the drug action.

Objective: To study the relationship between Fas protein expression and DNA content in non-small cell lung cancer (NSCLC)., Methods: Fas protein expression and DNA content in resected samples from 33 NSCLC patients and 17 normal controls were detected by flow cytometry. Fas expression and DNA content were compared with cell proliferation activity which was defined by proliferation index and s-phase fraction (SPF), and with clinicopathological parameters., Results: The percentage of DNA aneuploidy in NSCLC was 82%. The DNA index (DI), PI and SPF in NSCLC were 1.36 +/- 0.23, 0.29 +/- 0.09 and 0. 144 +/- 0.078 respectively, which were significantly higher than those in normal lung tissue. The Fas protein expression was lower in NSCLC than that in normal tissue (P = 0.000) and showed negative correlation with PI (P = 0.024) and SPF (P = 0.004). Fas expression and the cell proliferation activity were not correlated to the clinicopathological parameters including age, tumor size, lymph node metastasis and the histological types of lung cancer (P > 0.05)., Conclusions: Decrease of Fas protein expression and increase of proliferation activity are common in NSCLC. The reduction of Fas protein expression may affect the proliferation activity of NSCLC. This abnormal regulation of apoptosis and proliferation may play an important role in the pathogenesis of NSCLC.

The purpose of this investigation was to study the variation of p73 gene expression in the apoptotic process of acute myeloid leukemia (AML) cell line U937 induced by methotrexate (MTX). Morphological changes of apoptotic cells were observed with microscopy and Wright's + Giemsa staining. DNA ladder and cell cycle were examined by agarose gel electrophoresis and flow cytometry respectively. Using semi-quantitive reverse transcription-polymerase chain reaction (RT-PCR), the expression of p73 mRNA was examined. Results showed that MTX could induce U937 cell apoptosis effectively. Condensed nuclei, fragmentation of chromosome and DNA ladder were seen after 6 hour following treatment of MTX 5 micro mol/L. Sub-G(1) peak and S + G(2)/M arrest were also determined by FCM, but the quantity of p73 expression was generally constant. In conclusion, U937 cell apoptosis induced by MTX did not change p73 mRNA level.

Objective: To explore the molecular events and mechanism in the carcinogenesis of esophageal epithelium in the high incidence area of esophageal carcinoma., Methods: Epithelial cells collected from the high incidence area of esophageal carcinoma were used to detect DNA content and ploidy by propidium iodide(PI) stain. The expressions of p53, p16 and cyclin D1 were stained by indirect immunofluorescence of fluorescein isothiocyanate(FTTC), which were detected by flow cytometry (FCM)., Results: During the process of carcinogenesis, DNA content increased significantly. The diploid cells decreased while heteroploid cells increased sharply, with a heteroploidy rate of 84.2%. At the same time, the p53 protein accumulated and p16 was deleted. The positive rates of p53 and oncogene cyclin D1 were both 100%(5/5, 6/6) in the cancer group., Conclusion: In the early carcinogenesis of esophageal epithelium, DNA content and heteroploidy rates increase with tumor suppressor gene p16 deletion and p53 protein accumulation while oncogene cyclin D1 is overexpressed. Multiple molecular events have already occurred when esophageal carcinoma develops.

Objective: To study the effect of operative region hypermethylation gene in human malignant hematopoietic tumors., Methods: The abnormal methylation rate of P(15)(INK4B) gene 5'CpG island in 68 cases of malignant hematopoietic tumor samples were determined by methylation specific PCR using bisulfite modified DNA., Results: The methylation rates of P(15)(INK4B) were 84%, 0, 50% and 75%, respectively, for 25 cases of acute myeloid leukemia (AML), 15 chronic myeloid leukemia (CML), 16 myelodysplastic syndrome (MDS) and 12 multiple myeloma (MM). P(15)(INK4B) gene was frequently methylated in patients with high risk MDS and early stage of MM., Conclusion: Hypermethylation of P(15)(INK4B) gene is one of the main causes of its inactivation. Hypermethylation of CpG island was closely related to the development of malignant hematopoietic diseases.

Objective: To study the clinical and molecular biological characteristics of infant acute leukemia (IAL)., Methods: R and/or G banding technique was used for analysis of karyotype. DNA blotting for HRX gene rearrangement, and polymerase chain reaction (PCR) and reverse transcriptase PCR (RT-PCR) for fusion gene detection., Results: Twenty cases of IAL were detected. HRX gene rearrangement was found in 10 cases, including HRX/AF-4 fusion gene in 5, HRX/AF-9 fusion in 2, and HRX/ENL fusion in 1, HRX self-fusion mediated by alu-repeat homologous recombination and HRX/EEN fusion each in one (HRX/EEN is a novel fusion gene reported for the first time)., Conclusion: High frequency of HRX gene rearrangement occurred in IAL, which is characterised by a massive leukemia cell burden and 11q23 translocation, forming fusion genes, especially HRX/AF-4 (about 50%). The results are of important significance in guiding clinical treatment and approaching the etiology of IAL.

Objective: To investigate the homozygous deletion (HZD), hypermethylation and mutation of p16 gene in human breast cancer and the relationship between the structural alterations of p16 gene and its expression., Methods: PCR and PCR-methylation assay with silver staining (PCR-MASS) were used to detect HZD and hypermethylation of p16 gene exon 1 in 60 fresh breast cancers and 24 normal breast tissues adjacent to cancer (as control tissues). PCR-SSCP and DNA sequencing were used for the analysis of p16 gene mutation. Moreover, p16 gene and mRNA were also detected in the 60 cases., Results: Of the 60 breast cancers, HZD was found in 7 cases, hypermethylation and mutation were found in 16 and 4 cases respectively, and the difference was statistically significant. The positive rates of p16 protein and mRNA in breast cancer were 28/60 and 39/60 respectively., Conclusion: The results demonstrate that several kinds of p16 gene structural changes exist in breast cancer. The structural changes of p16 gene cause abnormal p16 expression, the main mechanisms are hypermethylation, while HZD or mutation are the secondary causes. Abnormal expression of p16 gene then becomes involved in the development and metastasis of breast cancer.

Objective: To figure out the mechanism of p16 gene inactivation in human bladder transitional cell carcinoma (BTCC)., Methods: p16 gene was analyzed for genetic alterations by Southern blot analysis, PCR-SSCP and DNA methylation analysis in 52 cases of transitional cell carcinoma of bladder., Results: p16 gene deletion was found in 11 of 52 (21.15%) BTCCs, only one tumor showed point mutation on p16 exon 2, nineteen cases of BTCCs (36.53%) showed p16 gene 5' CpG island methylation., Conclusion: There was a statistically significant association between p16 gene deletion and early stage, well differentiated tumors. Additionally, a statistically significant correlation was also noticed between p16 gene 5' CpG island methylation and tumors in late stage with poor cell differentiation.

Objective: To observe the effect of proliferating cell nuclear antigen (PCNA) antisense RNA on the growth characteristics of human gastric cancer cell., Methods: An eukaryotic expression vector pDR-PCNA with human PCNA gene insert in reverse direction was successfully constructed. The human gastric cancer cell line SGC-7901 was transfected with pDR-PCNA by lipofectamine., Results: Growth rate, protein and RNA biosynthesis and DNA contents in S-phase and G2/M-phase of the transfected SGC-7901 were significantly suppressed in comparison with those of the parental cell line., Conclusion: PCNA antisense RNA can significantly suppress the in vitro growth of gastric cancer cell line.

To investigate the antitumor activity of psoralen on mammary cancer cells of EMT6 line, the cytotoxity of the drug against EMT6 cells was tested by MTT assay; an experimental therapy was carried out in 15 nude mice that were subcutaneously injected with EMT6 cells; the morphological changes of tumor tissues were observed under electron microscope; and the DNA content was measured and analysed with a computerized MPV-microspectrophotometer. The result shows that psoralen has a strong antitumor effect on mammary cancer EMT6 cells both in vivo and in vitro, with an IC50 value of 2.23 micrograms/ml. The antitumor effect might be related to the relative decrease of cell DNA content and the degeneration and cavitation of cellular mitochondriums. Therefore psoralen may be an effective agent for the treatment of mammary cancer.

Vitamin A and its analogus, the retinoids, are agents that are known to induce differentiation and inhibit growth on cell in vitro and in vivo. These agents show promise as prophylactic and therapeutic ones in human cancer and were noted extensively by scholars abroad, but the research has just been developed in recent years in our country. Retinamide (named briefly R II), a kind of new retinoids made in China, can induce differentiation and inhibit growth of cell, but its toxic effect is smaller than its maternal chemical compound (retinoic acid). Using automatic image analysis technology, polyacrylamide gel LDH isoenzyme electrophoresis, radioimmunoassay and condensing reaction of Con A, we have observed induction of differentiation of the R II on SGC-7901 cells. Our experiments indicate that R II can inhibit cell proliferation, decrease obviously average DNA content and nuclear area, reduce CEA secretion and condensing of the cells, and change LDH isozymoraphy of SGC-7901 cell with promoting H-type LDH and reducing M-type LDH. The change of morphology under light microscope by R II showed that the cells spread, flattened and partially lined up, and the alkalophilic quality of cytoplasm became weak. These results suggest that SGC-7901 cell under the action of R II should undergo the changes of reverse differentiation in morphological, physiological and bio-chemical aspects.

In this study, the inhibitory effect of Yifei Kangliu Yin (YFKL) was observed on growth of LAX-83 human lung adenocarcinoma in naked mice. It was found that the YFKL could suppress the tumor growth significantly with a suppression rate of 45.59%. It was also found that positive expression of Ki-67 and cell proliferation significantly decreased, c-myc changed from positive to weak positive and P53 from positive to negative in the YFKL treated group. It suggested that the inhibitory effect of YFKL on proliferation of cancer cells might be realized by way of changing the oncogenetic expression of cancer, so as to influence the cell proliferation directly.

Background: The pleomorphic adenoma is the most frequent tumor of the human lacrimal gland comprising about 50% of the epithelial tumors of this organ. Although being benign, local recurrences can occur when the first removal was incomplete and malignant transformation is also not in frequent. It is well known that many sorts of cellular oncogene products are involved in the initiation, promotion and progression of the human neoplasm. Our purpose was to know whether there is abnormal expression of P21ras in pleomorphic adenoma., Methods: We have undertaken a study of the expression of P21ras in 5 normal tissues and 32 pleomorphic adenoma of lacrimal gland by immunohistochemical means using the monoclone antibody F-132-62 and the nuclear DNA content in the tumor was assayed by image analysis technique., Results: Normal tissues of lacrimal gland were negative, 12 tumors were stained positively with the antibody. The DNA content of 14 cases of tumor was increased. Their DNA ploidy distribution pattern showed two or several peaks. Good correlation has been found between the expression of P21ras and DNA ploidy distribution pattern, the DNA ploidy distribution pattern of tumor which expressed p21ras showed mainly two or several peaks. P< 0.05., Conclusions: The result of our studies may suggest that there are increased expression of p21ras in pleomorphic adenoma and the expression of p21ras is related to the promotion and progression of pleomorphic adenoma of lacrimal gland.

Objective: To obtain the information about whether expression of epidermal growth factor (EGF) receptor is related to the proliferative activity of tumor., Methods: The expression of EGF receptor and DNA content of pleomorphic adenoma of lacrimal gland in 32 cases were detected by an immunohistochemical avidin biotin peroxidase complex method and determined by an image analysis technique, respectively. The relationship between the expression of EGF receptor and DNA content was analyzed., Results: 10 tumors were stained positively with anti-EGF receptor antibody, the DNA contents of 14 cases were increased, their DNA ploidy distribution pattern showed two or several peaks. Good correlation has been found between the expression of EGF receptor and DNA ploidy distribution pattern, and the DNA distribution pattern of tumor with positive EGF receptor expression showed mainly two or several peaks (P < 0.01)., Conclusion: The expression of EGF receptor of pleomorphic tumor of lacrimal gland is related to the proliferative activity of tumor cells.

Mucoepidermoid carcinoma is the most common malignant tumor of salivary glands. In this report, we used hexamethylene bisacetamide (HMBA) as a inducer to induce human mucoepidermoid carcinoma cell line MEC-1 cells to differentiate. The growth kinetics, morphological changes and DNA contents of the cells were investigated. The results showed that HMBA-treated MEC-1 cells tend to become mature cells, implying that HMBA can induce differentiation of MEC-1 cells in vitro.

The relationship between ras activation and over expression of p21 protein and DNA content in progression from benign to malignant of gastric mucosa was studied. The point mutation at 12 of c-Ha-ras oncogene was detected with PCR and specific oligonucleotide probe hybridization, the expression of ras p21 and DNA ploidy by flow cytometry was also carried out simultaneously on 66 human gastric tissues with gastric cancer and precancerous lesions, some of the patients were followed up for 42 to 60 months. The results showed that: activation of ras oncogene and p21 overexpression may be involved in the early stages of gastric cancer; DNA aneuploidy may not help for the early diagnosis, but can be useful for the diagnosis of gastric cancer in pathology; gastric cancer with mutational activation at 12 of c-Ha-ras may has unfavourable future. It concluded that c-Ha-ras activation and p21 overexpression may be help to early diagnosis of gastric cancer in clinic.

The L1210 cells rapidly ceased to proliferate and its mitotic index decreased markedly after being exposed to HH07A 2 micrograms . ml-1 during exponential growth phase. However, 34.6% of the cells were still able to form colonies in soft agar if HH07A was removed after 24 h of incubation (the colony-forming efficiency for control cells was 63.7%) and the cell viability remained at about 94%. The DNA contents in L1210 cells were measured with a flow-cytometer. The results showed that the cell-cycle was blocked at the S phase and the number of cells in G2 + M phase decreased significantly. The time response course for L1210 cells indicated that the inhibitory effect of HH07A on L1210 clonogenic cells was slightly time dependent.

In order to study the role of insulin-like growth factor II (IGF-II) in the development of hepatocarcinoma (HCC), the expression of IGF-II, IGF-II receptor (IGF-IIR) and HBxAg in HCC was studied with immunohistochemistry (PAP method). Meanwhile DNA ploidy and S-phase fraction of hepatocytes were analyzed with flow cytometry. The results were as follows: (1) IGF-II, IGF-IIR and HBxAg showed positive staining simultaneously in the tumor tissues of 93% (n = 15) of the HCC cases with chronic liver disease and with positive evidence of HBV; (2) The mean S-phase incidence in tissues of IGF-II positive HCC was 28.6 +/- 6.4%; this was higher than 12.8 +/- 2.4% in the IGF-II negative tumors (P < 0.05); (3) The incidence of DNA-aneuploidy in IGF-II positive liver tissues was 100% (10/10); this was higher than 60% (6/10) in IGF-II negative liver tissues (P < 0.05). It is suggested that IGF-II might play an important role in the development of HCC when there is evidence of HBV and chronic liver disease involvement. IGF-II positive staining HCC have increased proliferative activity as compared with IGF-II negative staining tumors.

Retinoblastoma in nude mice as an animal model was developed by injecting cultured human retinoblastoma cell line(Rb) Y79 into the anterior chamber of eyeball. It was treated by direct injection of RGNTF-McAb into the Rb tumor. Ten out of 30 eyeballs with Rb inoculation did not develop tumor (32% inhibition) if Rb cell suspension was mixed with the RGNTF-McAb before injection; whereas in the control, all 40 but 3 eyeballs developed tumor (7%) when Rb cell suspension alone had been injected. This 32% of inhibition of Rb tumor formation by RGNTF-McAb was very significant (T > 2.58, P < 0.01). The results of immunotherapy of 46 eyeballs with Rb tumor developed 10 days after inoculation by RGNTF-McAb for 2 months revealed that the proportion of grade III-IV tumors before and after therapy reduced from 53% to 26% and that of grade I-II tumors increased from 47% to 74%. Feulgen DNA staining of tumor sections after therapy revealed that the average DNA contents in Rb cells decreased significantly (P < 0.01) from 16.2 +/- 2.6 in grade III-IV to 5.3 +/- 1.2 in grade I-II compared to that of the untreated control 18.8 +/- 3.2. Numerous white cells infiltrating the Rb tumor, hyperplasia of fibrous tissues, and no spreading and metastasis of the tumor tissue were observed in the treated eyeballs; whereas Rb tumor was spreading to the optic nerve and superior colliculus in the untreated eyeballs. Therefore, the RGNTF-McAb can not only inhibit the growth of Rb cells but also limit their spreading and metastasis.(ABSTRACT TRUNCATED AT 250 WORDS)

The dynamic changes of fibronectin (FN) content and nuclear features (DNA content, morphological parameters) during the development of hepatoma induced by 3'-Me-DAB were studied via computer-assisted image analysis. The results showed that the amount of FN decreased progressively and even disappeared completely during hepatocarcinogenesis. The difference between distinctive foci or nodules was highly significant (P less than 0.0001) and the DNA content was also increased coincidently during the same process.

After 24, 48 and 72 hours' treatment of cells of SGC-823 gastric carcinoma in cell cultures with ginseng volatile oil, glycogen, succinate dehydrogenase and DNA in single cells were measured quantitatively with MPV2 microscope photometer. The results show that the inhibition of cancer cell growth by ginseng volatile oil may be due to the action of metabolism of DNA, carbohydrates and energy.

The nuclear DNA content was measured by flow cytometry (FCM) in 167 specimens with normal nasopharyngeal epithelium, paracarcinoma tissue and nasopharyngeal carcinoma (NPC). Thirty eight (38%) of 101 NPC, seven (58%) of 12 recurrent and six (30%) of 20 paracarcinoma tissues were nondiploid. There was no nondiploid at all in 20 specimens of normal nasopharyngeal epithelium. Two of six patients with VCA-IGA(+) were nondiploid. Cellular proliferation index (PI) of NPC was increased significantly as compared with that of the normal epithelium (P < 0.01). However there was no marked difference in PI. between NPC and paracarcinoma tissues. The rate of cervical metastasis in nondiploid NPC was significantly higher than that in diploid NPC (P < 0.025). But there was no correlation of DNA content between the stage of the tumor and the titer of VCA-IGA. These data show that FCM may prove useful in the diagnosis and predication of prognosis in NPC.

The effects of irradiation and hyperthermia on the distribution in various phases and DNA content of HeLa S3 cells were analyzed by flow cytometry and an image analysis instrument. A marked increase in DNA content from 6.718 to 9.614(AU) in HeLa S3 cells after 6 Gy irradiation was seen to correspond with the changes in the distribution of various phases in G2 + M, from 22%-52%. Meanwhile, the surviving fraction of HeLa S3 cells after 6 Gy irradiation was less than 1%. However, after heating at 44 degrees C for 10 min, the amount of cells in G2 + M% increased from 22.5% to 52.5% and the surviving fraction after hyperthermia was less than 2.65%. The changes in distribution of various phases after Ir-192 irradiation were similar to those seen after X-ray irradiation. The delay of G2 + M phase after treatment with 8 Gy plus heating at 44 degrees C for 7 min in HeLa S3 cells was similar to that seen in the case of treatment with 8 Gy alone. As the surviving fraction accompanying the G2 + M delay after irradiation plus heat treatment was very low, we suggest that the changes of distribution in various phases of HeLa S3 cells after treatment might be used as a rapid indicator of serious injury.

After treatment with n-sodium butyrate for 7 days, the inhibition of growth rate of human gastric adenocarcinoma cell (MGc 80-3) in culture reaches 50.7%. About 90% of the cancer cells treated with the drug undergo obvious differentiation, and their ultrastructure is also changed. Moreover, the cancer cells which have hyperdiploid chromosomes increase from 78% to 96%; on the contrary, the percentage of hypertriploid cells decreases from 6% to 2%, while that of hypertetraploid cells diminishes from 14% to 2%. By using the combination of 3H-TdR autoradiography and Feulgen cytophotometry to measure the cellular DNA content of unlabelled cells (G1), it is shown that the DNA amount in the experimental group is lower than that in the control group. Furthermore, the DNA content of undifferentiated cells in the unlabelled cells (G1) of the experimental group is hyperhexaploid in amount (D1 = 3.76 and 3.56), and about 90% undifferentiated cells have a DNA value of over 6 C. On the other hand, the differentiated cells in the unlabelled cells on the above same slide have near-tetraploid DNA values (D1 = 2.03 and 1.99), and a DNA content below 4 C is found in about 60% differentiated cells. The difference in DNA amount between these two categories of cells is statistically significant. The results mentioned above suggest that although the amount of genetic material in the morphologically differentiated cells has markedly decreased, these cells still do not represent normal diploid cells.