Is early surveillance with CT scan necessary in patients with stage II/III colorectal cancer: a retrospective study.

BACKGROUND AND OBJECTIVES: This analysis aims to evaluate the value of early surveillance within 6 months after resection for stage II/III colorectal cancer (CRC). METHODS: Patients with stage II/III CRC who received surgery with curative intent for CRC were included. CT scans of the chest, abdomen, and pelvis performed within 6 months after surgery were evaluated. RESULTS: Among 150 patients included in the study, 10 patients (1 occurred in stage II disease and 9 occurred in stage III) were diagnosed as recurrence within 6 months after surgery. The proportion of patients diagnosed as recurrence was significantly higher in stage III disease than in stage II disease (P = 0.01). The likelihood of recurrence within 6 months was associated with the extent of lymph node metastases (r = 0.205, P = 0.012). Three patients with recurrent disease underwent salvage resection with curative intent. CONCLUSIONS: Early surveillance with CT scan within 6 months after curative resection may not be necessary for stage II disease. Although, the strategy may be helpful for stage III disease considering the high incidence of salvage surgery for recurrence disease, the early detection of recurrence could not be translated into survival benefit.

[Correlation of expression of Survivin, BCRP and HER-2 genes with therapeutic response of TE regimen neoadjuvant chemotherapy in breast cancer patients].

OBJECTIVE: To study the changes of expression of Survivin mRNA, BCRP mRNA and HER-2 mRNA in breast cancer after TE regimen neoadjuvant chemotherapy, and to find biological markers to predict the efficiency of TE regimen neoadjuvant chemotherapy. METHODS: The gene expressions were detected by RT-PCR from 56 breast cancer patients before and after TE regimen neoadjuvant chemotherapy (docetaxel and epirubicin). The relationships between these gene expressions and chemotherapy responses were analyzed. RESULTS: The overall response rate to neoadjuvant chemotherapy was 71.4%, including 8.9% (5/56) with complete response and 62.5% (35/56) with partial response. Pathological complete response was found in 4 cases (7.1%). Stable disease and progression of disease were 23.2% (13/56) and 5.4% (3/56), respectively. The expression of Survivin mRNA after neoadjuvant chemotherapy was 35.7% (20/56), significantly lower than 60.7% (34/56) before neoadjuvant chemotherapy (P = 0.008). The expression of BCRP mRNA after neoadjuvant chemotherapy was 19.6%, significantly lower than 37.5% before neoadjuvant chemotherapy (P = 0.036). The positive rate of HER-2 mRNA expression was 41.1% before the chemotherapy, and reduced to 21.4% after the chemotherapy (P = 0.025). The effective rates of the single positive expression of Survivin mRNA or BCRP mRNA were both lower than that of negative expression (P < 0.05). The level of HER-2 mRNA expression alone was not significantly associated with the effective rate of chemotherapy (P = 0.144). When the expression of all Survivin mRNA, BCRP mRNA and HER-2 mRNA were negative, the effective rate of neoadjuvant chemotherapy was higher than that in patients with positive expression (P = 0.003). The level of Survivin mRNA expression was not significantly associated with BCRP mRNA and HER-2 mRNA (P > 0.05). CONCLUSION: The expression of Survivin in combination with BCRP and HER-2 is associated with clinical response to TE neoadjuvant chemotherapy in breast cancer, and can be used as predictive biomarkers for chemosensitivity of TE regimen neoadjuvant chemotherapy for breast cancer.

[Distribution of hepatitis B virus genotypes and subgenotypes among chronically infected patients in Xinjiang Uighur.].

OBJECTIVE: To investigate the distribution of Hepatitis B virus genotypes and subgenotypes among patients with chronic hepatitis B in Xinjiang Uighur. METHODS: The HBV genotypes and subgenotypes were analyzed by PCR-restriction fragment length polymorphism in 109 patients with chronic hepatitis B. RESULTS: Two HBV genotypes, genotype C (45.9%) and genotype C/D (29.4%) were prevalent, genotype B (8.3%) and genotype D (16.5%) were also found in Xinjiang Uighur. Genotype C had two subgenotypes, C1 (54%) and C2 (46%). Genotype B had only one subgenotype, i.e. Ba. The subgenotype C2 was associated with cirrhosis and hepatocellular carcinoma. CONCLUSION: In Uygurs, the most common HBV genotypes were C and C/D, and the subgenotype C2 was associated with cirrhosis and hepatocellular carcinoma.

Efficacy of rituximab combined with CHOP for treating patients with diffuse large B-cell lymphoma.

BACKGROUND: This study aimed to evaluate the efficacy and safety of rituximab combined with cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) for treating patients with diffuse large B-cell lymphoma (DLBCL). METHODS: A total of 144 patients with DLBCL were randomly divided into intervention group and control group, 72 patients in each group. The patients in the control group received cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) chemotherapy, while the participants in the intervention group received R-CHOP. The primary endpoint was relapse-free survival (RFS) and the secondary endpoints were overall survival rate (OSR) and adverse events (AEs). RESULTS: One hundred thirty-four patients completed the study. The intervention with R-CHOP did not show greater efficacy than CHOP in the estimated median follow-up time (intervention group 33 months vs control group 29 months, P = .15). In addition, no significant differences in the 5-year RFS (intervention group 81% vs placebo group 76%, P = .28) or the 5-year OSR (intervention group 93% vs placebo group 91%, P = .53) were found between the 2 groups. The AEs were also similar between the 2 groups. CONCLUSION: This study demonstrated that R-CHOP, when compared with CHOP alone, could not improve the RFS and OS of patients with DLBCL. Additionally, both groups had similar safety profiles.

A novel hepatitis B virus genotyping system by using restriction fragment length polymorphism patterns of S gene amplicons.

AIM: Traditional hepatitis B virus (HBV) genotyping methods using restriction fragment length polymorphism (RFLP) can reliably identify genotypes A to F. As HBV genotypes G and H have been recently identified, this study was to establish an accurate and simple genotyping method for all eight HBV genotypes (A to H). METHODS: Two hundred and forty HBV small S sequences obtained from GeneBank were analysed for restriction enzyme sites that would be genotype-specific. Restriction patterns following digestion with restriction enzymes BsrI, StyI, DpnI, HpaII, and EaeI, were determined to identify all eight HBV genotypes. Mixed genotype infections were confirmed by cloning and further RFLP analysis. RESULTS: The new genotyping method could identify HBV genotypes A to H. Genotypes B and C could be determined by a single step digestion with BsrI and StyI in parallel. This was particularly useful in the Far East where genotypes B and C are predominant. Serum samples from 187 Chinese HBV carriers were analysed with this genotyping system, and the genotype distribution was 1.1% (2), 51.9% (97), 40.6% (76) and 4.8% (9) for genotypes A, B, C, and D, respectively. Mixed genotypes were found in only 3 patients (1.6%). Sequence data analysis confirmed the validity of this new method. CONCLUSION: This HBV genotyping system can identify all eight HBV genotypes. It is accurate and simple, and can be widely used for studies on HBV genotyping.

[The association of paraoxonase 2 gene C311S variant with ischemic stroke in Chinese type 2 diabetes mellitus patients].

OBJECTIVE: To investigate the association between the C311S polymorphism of paraoxonase 2 (PON2) gene and ischemic stroke in Chinese type 2 diabetes mellitus (T2DM) patients. METHODS: A case-control study of 279 Chinese subjects (including 162 T2DM with or without ischemic stroke and 117 non-diabetic control) was performed. Genotype frequencies of C311S polymorphism were studied by polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) analysis with DdeI digestion. RESULTS: C311S polymorphism of PON2 gene was detected in Chinese with the C/S allele frequencies 0.145 and 0.855. The frequency distribution showed significant difference between Chinese and Asian Indian. Furthermore, the genotype distribution (SS, CS and CC) of the PON2 C311S gene polymorphism exhibited a significant difference between T2DM patients complicated with ischemic stroke and T2DM without ischemic stroke, the former had a significantly higher C allele frequency(P<0.05). CONCLUSION: The above data indicate that the polymorphism at codon 311(Cys --> Ser)in the PON2 gene is associated with ischemic morbidity in Chinese T2DM patients and C allele might be a risk factor.

[Hepatitis B virus genotypes and the heterogeneity of its polymerase gene].

OBJECTIVE: To study the heterogeneity of polymerase gene (P gene) within hepatitis B virus (HBV) genotypes based on a systematic analysis of 202 HBV P genes, providing some useful references for further studies on the relationship among HBV genotypes, P gene mutations, replication and nucleoside analogues drug-resistance. METHODS: 202 HBV complete sequences containing P genes were obtained from GenBank and were analysed using computer softwares. RESULTS: There were some genotype-related characteristics of HBV P genes. As reverse transcriptase domain was concerned, there were more amino acid divergences in genotype C and D compared with these in genotype A. There were also amino acid substitutions in the A-F conserved regions of the reverse transcriptase domain within and between HBV genotypes. CONCLUSIONS: There are divergences of P genes and amino acids within and between HBV genotypes, which should be considered when amino acid changes are analyzed whether they are proposed to be drug-resistance mutations or the results from quasispecies-selected. Moreover, these divergences may affect the antiviral effect of nucleoside analogues on HBV with different genotypes.

[Construction of whole-genome lamivudine-resistant hepatitis B virus mutant and its replication and expression in HepG2 cells].

OBJECTIVE: To observe the changes of replication and antigen expressions of lamivudine-resistant hepatitis B virus (HBV) with polymerase gene mutation. METHODS: With site-directed mutagenesis, we constructed 3 HBV plasmids with polymerase gene mutation based on the template P3.8II. All the plasmids were transfected into HepG2 cells, in which the replication and expression of the virus were analyzed. RESULTS: The 3 polymerase gene mutant HBVs were successfully constructed. HBsAg and HBeAg expressions were detected in the supernatants of HepG2 cells transfected with these plasmids. The replication of the 3 mutant plasmids with rtG172E, rtG174C and rtG172E/rtG174C mutation decreased significantly in comparison with the wild-type virus. CONCLUSION: The 3 polymerase gene mutant HBVs shows depressed capacity for viral replication, and in vitro drug sensitivity study is needed to establish the relationship between these mutations and nucleoside analogue resistance.

Construction of HBV-specific ribozyme and its recombinant with HDV and their cleavage activity in vitro.

AIM:To construct the recombinant of HDV cDNA and HBV specific ribozyme gene by recombinant PCR in order to use HDV as a transporting vector carrying HBV-specific ribozyme into liver cells for inhibiting the replication of HBV.METHODS:We separately cloned the ribozyme (RZ) gene and recombinant DVRZ (comprising HDV cDNA and HBV-specific ribozyme gene) into the downstream of T7 promoter of pTAdv-T vector and studied the in vitro cleavage activity of their transcripts (rRZ, rDVRZ) on target RNA (rBVCF) from in vitro transcription of HBV C gene fragment(BVCF).RESULTS:Both the simple (rRZ) and the recombinant ribozyme rDVRZ could efficiently catalyze the cleavage of target RNA (rBVCF) under different temperatures (37°, 42° and 55°) and Mg(2+) concentrations (10mmol/L, 15mmol/L and 20mmol/L) and their catalytic activity tended to increase as the temperature was rising. But the activity of rRZ was evidently higher than that of rDVRZ.CONCLUSION:The recombinant of HDV cDNA and ribozyme gene had the potential of being further explored and used in gene therapy of HBV infection.

[Construction and in vitro activity of specific dual-ribozyme against alpha 1 (I) and (III) procollagen genes].

Overexpression of procollagen gene can cause the extraordinary increase of collagen's synthesis and therefore lead to the keloid and hypertrophic scar. To utilize ribozyme to suppress the expression of procollagen genes, a eukaryotic expression recombinant plasmid containing a dual-ribozyme gene against alpha 1 (I) and alpha 1 (III) procollagen genes was constructed. The ribozyme from in vitro transcription was incubated with target transcripts from recombinant plasmids which separately contained the fragments of the second exons of pro alpha 1 (I) and pro alpha 1 (III) collagen genes under various experimental conditions. The results showed that the dual-ribozyme could efficiently catalyze the specific cleavage of the target RNAs at 37 degrees C, 42 degrees C, 50 degrees C and Mg2+ concentration from 10 mmol/L to 20 mmol/L. This work provided a basis for further study on the ribozyme to suppress the expression of procollagen genes and control the cicatrization.