The clinicopathological significance of miR-149 and PARP-2 in hepatocellular carcinoma and their roles in chemo/radiotherapy.

Hepatocellular carcinomas (HCC) are commonly diagnosed at an advanced stage with unresectable tumors. Although numerous non-surgical approaches have been developed to treat HCC, the prognosis of patients with HCC is still poor. This study investigated the expression of miR-149 and PARP-2 in HCC tumor tissues and their roles in sensitizing chemo/radiotherapy. The expression of miR-149 was measured by real-time PCR, and PARP-2 protein was measured by immunohistochemistry and Western blot. The xenograft HCC mouse model was established by inoculating Hep G2 cells. Increased PARP-1 and decreased miR-149 expression was observed in HCC tissues compared to peritumoral tissues. Positive PARP-2 and low miR-149 expression correlated with larger tumor mass size (P < 0.001), capsular and vascular invasion (P < 0.001), lymph node metastasis (P = 0.02), high histological grade (P < 0.001), TNM (P < 0.001), and BCLC grade (P = 0.001). The Kaplan-Meier survival analysis showed a negative correlation between high PARP-2 expression or low miR-149 expression in HCC tissues with the survival of patients. High PARP-2 and low miR-149 correlated with a low 5-year survival rate and are poor prognosis factors. Overexpression of miR-149 or inhibition of PARP-2 expression could inhibit tumor growth but was more effective in sensitizing chemotherapy and radiotherapy in xenograft HCC animal models. Increased PARP-2 expression and loss of miR-149 expression are involved in the pathogenesis of HCC and are poor prognosis factors in patients with HCC. Although both miR-149 overexpression and PARP-2 inhibitor exert some antitumoral effect, PARP-2 inhibitor is a chemo/radio sensor and can be used to enhance chemotherapy and radiotherapy in patients with HCC.

Enhanced antiproliferative and apoptosis effect of paclitaxel-loaded polymeric micelles against non-small cell lung cancers.

Amphiphilic copolymer monomethoxy poly(ethylene glycol)-poly(caprolactone)-D-α-tocopheryl polyethylene glycol 1000 succinate (MPEG-PCL-TPGS) was prepared. In the present study, MPEG-PCL-TPGS was used as a novel nanovehicle for the delivery of paclitaxel (PTX) in the treatment of resistant lung cancers. The PTX-loaded MPEG-PCL-TPGS (PTX/MPT) micelles exhibited sustained release profile (168 h) with accelerated drug release at acidic pH conditions. The blank polymeric micelles showed excellent biocompatibility with cell viability of >85 %, making it suitable for all in vivo applications. PTX/MPT micelles displayed superior cytotoxicity in A-549 lung cancer cells than that of free PTX. The selective delivery of PTX to cancer cells resulted in enhanced cancer cell death. The PTX/MPT micelles showed higher cellular uptake via endocytosis pathways. The PTX-bound micelles preferentially arrested the cells at G2/M phase and showed a marked increase in sub G1 cell population (∼ 20 %). The pharmacokinetic study revealed a long blood circulation for PTX/MPT micelles. Finally, micellar formulation showed a remarkable tumor suppression effect in resistant A549/Taxol cells bearing xenograft nude mice along with no toxicity profile. The results indicate that the PTX-loaded biocompatible polymeric nanosystem could act as a potential delivery system for the treatment of lung carcinomas.

The regulatory mechanism of CCR7 gene expression and its involvement in the metastasis and progression of gastric cancer.

Gastric cancer is the second leading cause of cancer mortality, but the molecular mechanisms underlying its progression and metastasis remain unclear. CCR7 and Dicer 1 protein expression in 80 gastric adenocarcinomas and 40 peritumoral tissues were measured by immunohistochemical staining. The expression of let-7a miRNA in serum, tumor tissues, and peritumoral tissues was measured by real-time PCR. The role of let-7a in CCR7 protein expression, migration, and invasion of gastric cancer cells was tested in vitro. Dicer 1 protein expression was found to be significantly reduced, whereas CCR7 protein expression was significantly increased in gastric adenocarcinomas compared to peritumoral tissues. The let-7a miRNA levels in the serum and tumor tissues of gastric adenocarcinoma patients were significantly lower than in the serum of healthy controls and peritumoral tissues, respectively. Dicer 1 protein positively correlated with let-7a miRNA level, but negatively correlated with CCR7 protein level in gastric adenocarcinoma. Negative Dicer 1 protein and let-7a miRNA expression and positive CCR7 protein expression significantly correlated with lymph node metastasis, depth of invasion, high clinical TNM stage, and larger tumor size. Let-7a transfection significantly inhibited CCR7 protein expression, migration, and invasion of MNK-45 cells in vitro. High expression of CCR7 protein and low expression of Dicer 1 protein and let-7a miRNA are significantly associated with the metastasis and progression of gastric cancer. High CCR7 protein expression may be caused by the loss of Dicer 1 protein expression and reduced let-7a miRNA level in gastric cancer. The serum let-7a level might be a marker for the diagnosis of gastric cancer.

Green tea consumption and risk of esophageal cancer: a meta-analysis of epidemiologic studies.

BACKGROUND: Green tea has shown the role of chemoprevention for cancer. Recently, several studies suggested that green tea intake may have effect on esophageal cancer risk, whereas the results were inconsistent. METHODS: We performed a meta-analysis of all English and Chinese language studies of green tea consumption and esophageal cancer risk indexed in Medline, Embase, the Science Citation Index, the Chinese Biomedical Database and Wanfang Data from 1980 to June 2012. After reviewing each study, extracting data, and evaluating heterogeneity (Chi-square-based Q test and Ι2) and publication bias (Begg and Egger test), a meta-analysis was performed to evaluate the association between high/medium/low green tea consumption and non-drinking esophageal cancer risk. Pooled relative risk (RR) or odds ratio (OR) with 95% confidence intervals (CIs) were calculated using the fixed- or random-effect models. RESULTS: Ten eligible epidemiologic studies including 33731 participants and 3557 cases for esophageal cancer were included. Eight of which were case-control studies, and two were cohort studies. Overall, there were no association between high/medium/low green tea consumption and non-drinking risk of esophageal cancer (High: highest vs non-drinker: RR/OR = 0.76, 95% CI: 0.49 to 1.02. Medium: drinker vs non-drinker: RR/OR = 0.86, 95% CI: 0.70 to 1.03. Low: lowest vs non-drinker: RR/OR = 0.83, 95% CI: 0.58 to 1.08). When stratified analyses according to study design (case-control and cohort studies), country (China and Japan), participates source (population-based and hospital-based case-control), and gender (female and male), there were significant association between high/medium/low green tea consumption and non-drinking risk of esophageal cancer among female (High: RR/OR = 0.32, 95% CI: 0.10 to 0.54. Medium: RR/OR = 0.43, 95% CI: 0.21 to 0.66. Low: RR/OR = 0.45, 95% CI: 0.10 to 0.79), but not the others. CONCLUSIONS: We did not found significant association between green tea consumption and non-drinking esophageal cancer risk, but an evidence of protective effect was observed among female.

Thermoreversible gel-sol behavior of biodegradable PCL-PEG-PCL triblock copolymer in aqueous solutions.

A series of biodegradable PCL-PEG-PCL block copolymers were successfully synthesized by ring-opening polymerization of epsilon-caprolactone initiated by poly(ethylene glycol) (PEG), which were characterized by (1)H NMR, (13)C NMR, and FTIR. Their aqueous solution displayed special gel-sol transition behavior with temperature increasing from 4 to 100 degrees C, when the polymer concentration was above corresponding critical gel concentration (CGC). The gel-sol phase diagram was recorded using test tube inverting method and DSC method, which depended not only on chemical composition of copolymers, but also on heating history of copolymer's aqueous solution. As a result, the gel-sol transition temperature could be adjusted, which might be very useful for its application in biomedical fields such as injectable drug delivery system. And the typical shell-core structure of PCL-PEG-PCL micelles was introduced. The micelle-packing and partial crystallization might be the key gelation machanism for this gel-sol transition behavior of PCL-PEG-PCL aqueous solution.

Preparation and antibacterial activity of compound chitosan-compound Yizhihao-nanoparticles.

OBJECTIVE: To prepare chitosan (CS)-compound Yizhihao-nanoparticles (NP) and to investigate its antibacterial activity. METHODS: CS NPs were formed by the incorporation of CS and Na3 PO4. CS-compound Yizhihao NPs were prepared by ion-cross-linking. The particle sizes and surface charges of CS NPs were determined by Malvern Zetasizer 1000-HAS and atomic force microscope (AFM), respectively. The antibacterial activity of CS-compound Yizhihao-NPs was studied in vitro and compared with that of compound Yizhihao powder. RESULTS: Malvern Zetasizer 1000-HAS and AFM demonstrated that the diameter of CS-compound Yizhihao NPs was (137.00+/-14.28)nm and CS NPs had (16.90+/-1.32)mV positive surface charges. The minimal inhibitory concentrations (MIC) of CS-compound Yizhihao NPs on Staphylococcus aureus,Pneumococcus,beta-hemolytic streptococcus, and Escherichia coli were 1:32,1:32,1:16,and 1:2, respectively. The minimal bactericidal concentrations (MBC) of CS-compound Yizhihao-NPs on Staphylococcus aureus, Pneumococcus, beta-hemolytic streptococcus, and Escherichia coli were 1:16,1:16,1:8, and 1:2, respectively. The antibacterial efficacy of CS-compound Yizhihao-NPs to Staphylococcus aureus, Pneumococcus, and beta-hemolytic streptococcus had been improved significantly (P< 0.05). CONCLUSION: CS-compound Yizhihao-nanoparticles have obvious antibacterial activity to the Staphylococcus aureus,Pneumococcus,and beta-hemolytic streptococcus,which lays the experimental foundation for new preparation of traditional Chinese medicine in future research.

[Manufacture of high frequency direct current dental X-ray machine].

This paper introduces five dental X-ray machines which are manufactured with IGBT to realize high frequency, real-time sampling and PWM to ensure the closed-loop control for tube current and Anodes's high voltage. These five machines also use microcomputer and combined X-ray tube for precise control. The sets don't have high voltage outside. The error of tube voltage is less than 1% and exposure time is less than 3%. The photos of pulp cavity and surrounding tissue can be seen clearly. These sets surely meet the requirements of perspective use in clinical.

Expression, purification, crystallization and preliminary X-ray diffraction analysis of the VP8* sialic acid-binding domain of porcine rotavirus strain OSU.

The rotavirus outer capsid spike protein VP4 is utilized in the process of rotavirus attachment to and membrane penetration of host cells. VP4 is cleaved by trypsin into two domains: VP8* and VP5*. The VP8* domain is implicated in initial interaction with sialic acid-containing cell-surface carbohydrates and triggers subsequent virus invasion. The VP8* domain from porcine OSU rotavirus was cloned and expressed in Escherichia coli. Different crystal forms (orthorhombic P2(1)2(1)2(1) and tetragonal P4(1)2(1)2) were harvested from two distinct crystallization conditions. Diffraction data have been collected to 2.65 and 2.2 A resolution and the VP8*(65-224) structure was determined by molecular replacement.

The prospective preventative HIV vaccine based on modified poliovirus.

In order to control HIV pandemic, many vaccines are invented. Although none first verified its efficacy in clinic, we hypothesize that HIV vaccine based on poliovirus is potential to develop the promising one, because it can elicit the broad immune response including the main mucosal, humoral and cellular reaction. However, the viral neural virulence is one major concern. The attenuated Sabin strain is a better candidate. While partial poliovirus genes are replaced by HIV antigen genes, the defective interfering particle will fail to produce progeny virions, which may further ensure its security. Although the vaccinal immune efficacy was verified in some similar animal experiments based on poliovirus to express the exogenous genes, more animal and clinical immune trials about HIV-poliovirus chimeric minireplicons are to be carried out and the hypotheses are to be validated.

Mutation analysis of the checkpoint kinase 2 gene in colorectal cancer cell lines.

BACKGROUND: Checkpoint kinase 2 (CHK2) is a DNA damage-activated protein kinase which is involved in cell cycle checkpoint control. CHK2 gene could be a candidate gene for colorectal cancer susceptibility. But there are few systematic reports on mutation of CHK2 in colorectal cancer. METHODS: The mutations of all 14 exons of CHK2 in 56 colorectal cancer cell lines were screened systematically, using denaturing high-performance liquid chromatography (DHPLC) to screen the mismatches of the CHK2 exons amplified products, and then the suspected mutant cell lines were scanned by nucleotide sequence analysis. RESULTS: VACO400 in CHK2 exon 1a was suspected to have mutation by DHPLC and confirmed by sequence, but this was nonsense mutation. C106, CX-1, HT-29, SK01, SW480, SW620 and VACO400 in CHK2 exon 1b were confirmed to have the same nonsense mutation in 11609 A > G. DLD-1 and HCT-15 in CHK2 exon 2 were confirmed to have missense mutation R145W, which was heterozygous C > T missense mutation at nucleotide 433, leading to an Arg > Trp substitution within the FHA domain. CONCLUSIONS: The CHK2 mutation in colorectal cancer is a low frequency event. There are just 10 cell lines to have sequence variations in all the 14 exons in 56 colorectal cancer cell lines and only DLD-1/HCT-15 had heterozygous missense mutation. These findings may give useful information of susceptibility of colorectal cancer as single nucleotide polymorphysim.

[Transhepatic arterial chemoembolization with gemcitabine and carboplatin for the treatment of stage III hepatocellular carcinoma].

OBJECTIVE: To evaluate the efficiency and safety of transhepatic arterial chemoembolization (TACE) with gemcitabine and carboplatin for the treatment of stage III hepatocellular carcinoma (HCC). METHODS: Sixty-one HCC patients were treated by TACE. During TACE, At first, intra-arterial infusion of carboplatin 300 mg/m2, then gemcitabine 1000 mg/m2 with 5-30 ml of ultra-lipoidal iodide oil emulsion was used for arterial embolization. The toxicity and hepatic damage were observed according to WHO anticancer drug toxicity criteria and Child-Pugh classification criteria, respectively. The survival time was also observed during follow-up. RESULTS: The blood toxicity was bone marrow suppression presented as grade I leucopenia in 39.3%, grade II in 29.5%, grade III-IV in 18.0%. Grade II-III nausea and vomiting developed in 96.8% of the patients. Hepatic function damage became aggravated in 16 patients from A to B class, in 2 from A to C class, and in 6 from B to C class according to Child-Pugh classification criteria. The median survival time was 20 months with a range of 5 to 3 5 months. CONCLUSION: Transhepatic arterial chemoembolization using carboplatin and mixture of gemcitabine with ultra-lipoidal iodide oil emulsion is safe and effective in the management of stage III hepatocellular carcinoma. This regimen can also improve their quality of life.

[Sentinel lymph node mapping in colorectal cancer: study of 45 cases].

OBJECTIVE: To discuss the sentinel lymph node (SLN) mapping technique in colorectal cancer and its feasibility and utility. METHODS: The dye lymphazurin was injected subserosally around the tumor during operation in 43 colorectal cancer, 20 males and 25 females, aged 49.5 (27 - 72) so as to find the SLNs. Fast-frozen pathology and routine pathology were performed too. RESULTS: SLN was successfully identified in 42 of the 45 patients, with a successful biopsy rate of 93.3%. In these 45 patients, there were 250 lymph nodes examined, of which 52 nodes were identified as SLNs. The sensitivity was 90.4% (20/22), the specificity was 95.2% [(20 + 20)/42], and the false negative rate was 15% (3/20). CONCLUSION: SLN mapping in colorectal cancer plays an important role in diagnosing metastasis of lymph nodes, and can be used to direct the clinical surgery.

[Oral ferric ammonium citrate solution in MRCP for diagnosing low-level obstructive jaundice].

OBJECTIVE: To evaluate the value of oral ferric ammonium citrate solution as a gastrointestinal contrast agent in diagnosing low-level obstructive jaundice. METHODS: Thirty-six patients who were suspected of low-level obstructive jaundice were performed with magnetic resonance cholangiopancreatography (MRCP) and conventional MRI before and after the administration of oral ferric ammonium citrate solution. The diagnostic accuracy for evaluating the site and the cause of obstruction was compared with other diagnostic modalities. RESULTS: The image qualities of single-slice and multi-slice MRCP were improved markedly. The accuracy of MRCP for evaluating the site of obstruction was 97.22%, which was superior to US (P<0.05). There were no significant differences among the MRCP, CT, and ERCP. CONCLUSION: Oral ferric ammonium citrate solution can significantly improve the image quality of MRCP. FAC-MRCP is a simple, safe, and noninvasive technique with excellent accuracy in the diagnosis of low-level obstructive jaundice.

Expression, purification and bioactivity of human augmenter of liver regeneration.

AIM: To construct the expression vectors for prokaryotic and eukaryotic human augmenter of liver regeneration (hALR) and to study their biological activity. METHODS: hALRcDNA clone was obtained from plasmid pGEM-T-hALR, and cDNA was subcloned into the prokatyotic expression vector pGEX-4T-2. The recombinant vector and pGEX-4T-2hALR were identified by enzyme digestion and DNA sequencing and transformed into E coli JM109. The positively selected clone was induced by the expression of GST-hALR fusion protein with IPTG, then the fusion protein was purified by glutathine s-transferase (GST) sepharose 4B affinity chromatography, cleaved by thrombin and the hALR monomer was obtained and detected by measuring H thymidine incorporation. RESULTS: The product of PCR from plasmid pGEM-T-hALR was examined by 1.5% sepharose electrophoresis. The specific strap was coincident with the theoretical one. The sequence was accurate and pGEX-4T-hALP digested by enzymes was coincident with the theoretical one. The sequence was accurate and the fragment was inserted in the positive direction. The recombinant vector was transformed into E coli JM109. SDS-PAGE proved that the induced expressive fusion protein showed a single band with a molecular weight of 41 kDa. The product was purified and cleaved. The molecular weights of GST and hALR were 26 kDa, 15 kDa respectively. The recombinant fusion protein accounted for 31% of the total soluble protein of bacterial lysate. HALR added to the culture medium of adult rat hepatocytes in primary culture and HepG2 cell line could significantly enhance the rate of DNA synthesis compared to the relevant control groups (P < 0.01). CONCLUSION: Purified hALR has the ability to stimulate DNA synthesis of adult rat hepatocytes in primary culture and HepG2 cells in vitro, and can provide evidence for its clinical application.

Liver targeting and the delayed drug release of the nanoparticles of adriamycin polybutylcyanoacrylate in mice.

BACKGROUND: Liver targeting drug delivery systems can improve the curative effects and relieve the cytotoxicity of the chemotherapy drugs in the treatment of liver diseases. Nanoparticles carrying therapeutic drugs are currently under hot investigation with great clinical significance. This study was aimed to investigate the different tissue distribution of the adriamycin polybutylcyanoacrylate nanoparticle (ADM-PBCA-NP) in the mice body after an injection via lateral tail vein, and to study the liver targeting effects of ADM-PBCA-NP in different diameters on normal mice liver. METHODS: One hundred and eighty Kunming mice were randomly divided into 6 groups with 30 mice in each group (5 treatment groups of ADM-PBCA-NP in the different diameter ranges, non-conjugated free adriamycin injection was employed as the control group). A single dose of either conjugated or free adriamycin equaled 2 mg/kg of body weight was delivered via the tail vein. Five mice in each trail were sacrificed at 5, 15, 30 minutes, 1, 5 and 12 hours postinjection, respectively. The adriamycin concentrations in the respectively collected liver, kidney, spleen, heart, lung and plasma were demonstrated using a high performance liquid chromatography with fluorescence detector. RESULTS: Compared with the control group, adriamycin was hardly detected in the heart muscle of the treatment groups (P < 0.05). The nanoparticle-conjugated adriamycin was cleaned up quickly from the kidney tissue. The adriamycin concentrations of the mice liver and spleen in the experimental groups were significantly higher than that in the control group, except for the group with the nanoparticles diameters of (22.3 +/- 6.2) nm (P < 0.05). The ADM-PBCA-NP in (101.0 +/- 20.3) nm diameter had the highest liver distribution, and the second highest adriamycin distribution in liver was the group of (143.0 +/- 23.5) nm diameter (P < 0.05). Moreover, adriamycin was released slowly in the liver during the detection period in the experimental groups. ADM-PBCA-NP in (22.3 +/- 6.2) nm diameter was not distributed in the tissue of the liver, kidney, heart, spleen, and lung. CONCLUSIONS: ADM-PBCA-NP in 100 - 150 nm diameter range has the best liver targeting with a characteristic of slow medicine release. It also decreases the medicine distribution in the heart, kidney and lung. In the treatment of liver cancer, the polybutylcyanoacrylate nanoparticles system has a good liver targeting ability, which increases the anticancer activity and markedly decreases the toxicity of adriamycin.

Diagnosis and treatment of penetrating anorectal wounds.

OBJECTIVE: To research the diagnosis and effective treatment of penetrating anorectal wounds. METHODS: Retrospective analysis was done in 16 cases of penetrating anorectal wounds from 1985 to 2004. Debridement and suture of anorectal and vesical wounds, effective diversion of fecal and urinary stream and sufficient presacral drainage were performed in all cases. RESULTS: All the 16 cases were cured. Among them, 2 cases with infection in presacral space were cured by sufficient drainage after operation, one case was cured by secondary repair after anal sphincter was repaired unsuccessfully and one case with rectovesical fistula was cured with conservative treatment. None of them suffered from complications such as anal stenosis, dysuria or impotence etc. CONCLUSIONS: For penetrating anorectal wound, to master early recognition of concomitant injures, to select appropriate surgical intervention and to strengthen perioperative treatment are the keys to improve the curative effects.

[Application of nanobiological technology in medicine and its advances in China].

Nanobiological technology is an important research field in nanotechnology and has extensive applications in medicine. Although initiated lately, application of nanobiological technology in medicine is advancing in good pace in China, mainly involves in fields including nano-scale pharmaceutical carrier, nanoscale diagnostic technology, nanobiomaterials, and nano-scale traditional Chinese medicine.

[Study of the methods of wavelet feature extraction and neural network classification of fluorescence spectra to improve the diagnostic rate of colonic earlier stage cancer].

In order to improve the diagnostic rate of earlier stage colonic cancer with laser-induced 5-ALA-Pp IX fluorescence spectra, a novel method of extraction of fluorescence spectral feature using wavelet analysis and classification using artificial neural network trained with resilient back-propagation algorithm (R-BPNN) was developed. 504 spectra were collected from 8 normal SD rats, and 20 1,2-DMH-induced SD colon cancer models and 12 second generation rats of induced rats. 150 min later trail intravenous injections of 5-ALA dose of 25 mg x kg(-1) body weight (BW), and fluorescence spectra excited with 370 nm Ti-laser were collected in vivo. After preprocessing, 12 feature variants were extracted with wavelet analysis. With R-BPNN, all spectra were classified into two categories: normal or abnormal, which included dysplasia, early carcinoma (EC) and advanced carcinoma (AC). The sensitivity and specificity were 98.91% and 97.2% respectively. The accuracy of discriminating dysplasia, early carcinoma, and advanced carcinoma from normal tissue were 91.3%, 98.9% and 98.8 respectively. The result indicated that this method could effectively and easily diagnoses earlier stage colonic carcinomas.

Combination of telomerase antisense oligonucleotides simultaneously targeting hTR and hTERT produces synergism of inhibition of telomerase activity and growth in human colon cancer cell line.

AIM: To investigate synergism of inhibition of telomerase activity and proliferation of human colon cancer cells by combination of telomerase antisense oligonucleotides (ASODNs) simultaneously targeting human telomerase RNA (hTR) and human telomerase reverse transcriptase (hTERT) in vitro. METHODS: ASODN of hTR and ASODN of hTERT were transfected into human colon cancer SW480 cells by liposomal transfection reagents. Telomerase activity of SW480 cells was examined using telomeric repeat amplification protocol (TRAP)-enzyme-linked immunosorbent assay (PCR-ELISA). Proliferation activity of SW480 cells was tested by methyl thiazolyl tetrazolium assay. Apoptosis and cell cycle were analyzed by flow cytometry. RESULTS: The telomerase activity and cell survival rate in SW480 cells transfected with 0.2 mumol/L of ASODN of hTR or ASODN of hTERT for 24-72 h were significantly decreased in a time-dependent manner compared with those after treatment with sense oligonucleotides and untreated (telomerase activity: 24 h, 73%, 74% vs 99%, 98%; 48 h, 61%, 55% vs 98%, 99%; 72 h, 41%, 37% vs 99%, 97%; P<0.01; cell survival rate: 24 h, 88%, 86% vs 94%, 98%; 48 h, 49%, 47% vs 94%, 97%; 72 h, 44%, 42% vs 92%, 96%; P<0.01). Moreover, the telomerase activity and the cell survival rate in SW480 cells treated by the combination of telomerase anti-hTR and anti-hTERT were more significantly suppressed than single anti-hTR or anti-hTERT (telomerase activity: 24 h, 59% vs 73%, 74%; 48 h, 43% vs 61%, 55%; 72 h, 18% vs 41%, 37%; P<0.01; cell survival rate: 24 h, 64% vs 88%, 86%; 48 h, 37% vs 49%, 47%; 72 h, 25% vs 44%, 42%; P<0.01). Meanwhile, the apoptosis rates in the combination group were markedly increased compared with those in the single group (24 h, 18.0% vs 7.2%, 7.4%; 48 h, 23.0% vs 13.0%, 14.0%; 72 h, 28.6% vs 13.2%, 13.75; P<0.01). Cells in combination group were arrested at G(0)/G(1) phase. CONCLUSION: Telomerase anti-hRT and anti-hTERT suppress telomerase activity, and inhibit growth of human colon cancer cells probably via induction of apoptosis and retardation of cell cycle. Additionally, combined use of telomerase ASODNs targeting both hTR and hTERT yields synergistic action selective for human colon cancer.

[Study of a multivariate statistical 5-ALA-based discrimination method for fluorescence spectra of colonic tissue of SD rats].

In order to diagnosis colon early cancer with laser-induced 5-ALA-PpIX fluorescence spectra, a multivariate statistical method to distinguish these fluorescence spectra acquired in vivo was developed. 343 spectra were collected from 8 normal SD rats, and 20 1,2-DMH-induced SD colon cancer models, and 12 second generation rats of induced rats. 150 min after trail intravenous injections of 5-ALA at a dose of 25 mg x kg(-1) BW, fluorescence spectra excited with 370 nm Ti-laser were collected in vivo. All spectra were divided into a calibration group and a prediction group. After preprocessing, 4 principal components were extracted with PCA. And then, discrimination models were built by stepwise multivariate logistic regression (SMLR) on calibration group. 3 pathological styles were combined each other, and then 3 SMLR models were derived. Normal tissues were classified from early cancers and advanced cancers with sensitivity of 100% and 98.4%, and specificity of 96% and 100%, and accuracy of 98% and 99.2% on prediction group, respectively. The multivariate statistical discrimination method of PCA and SMLR together can effectively distinguish normal tissues from early cancers and advanced cancers with high sensitivity and specificity by means of systemic 5-ALA at low dose. Laser induced fluorescence 5-ALA-based technique is promising for the detection of colonic early cancer.