Graphene oxide-hydroxyapatite nanocomposites effectively deliver HSV-TK suicide gene to inhibit human breast cancer growth.

Gene therapy with herpes simplex virus thymidine kinase gene (HSV-TK), which is also known as "suicide" gene therapy, is effective in various tumor models. The lack of a safe and efficient gene delivery system has become a major obstacle to "suicide" gene therapy. In this study, the cytotoxicity and transfection efficiency of graphene oxide-hydroxyapatite (GO-Hap) were analyzed by MTS and flow cytometry, respectively. A series of assays were performed to evaluate the effects of GO-HAp/p-HRE/ERE-Sur-TK combined with ganciclovir treatment on growth of human breast normal and cancer cells. The results showed that GO-HAp nanocomposites effectively transfected cells with minimum toxicity. GO-HAp/p-HRE/ERE-Sur-TK combined with ganciclovir treatment inhibited the proliferation and induced cell apoptosis in cancer cells, while the cytotoxic effects are tolerable in normal breast cells. We conclude that the GO-HAp nanocomposites have significant potential as a gene delivery vector for cancer therapy.

[Dendritic cells and acute myeloid leukemia].

Dendritic cells can be derived from leukemia cells and normal precursor cells in the patients with acute myeloid leukemia (AML). Dendritic cells may capture leukemia antigen in bone marrow or lymph nodes, and present leukemia common antigen to stimulate proliferation of specific CD8(+) T cells, playing anti-leukemia effect. Dendritic cells for clinical and experimental use are transformed from leukemia cells and peripheral blood mononuclear cells and loaded in vitro with leukemia -specific or tumor common antigen, play a therapeutic role after reinfusion. This article reviews dendritic cells in the immunotherapy of AML.

N-3 PUFAs have antiproliferative and apoptotic effects on human colorectal cancer stem-like cells in vitro.

The n-3 polyunsaturated fatty acids have been shown to inhibit the induction and progression of many kinds of tumor and to increase the therapeutic effects of numerous chemotherapeutics, but their anticancer effect on cancer stem cells from colorectal cancer has not been described previously. In the present study, we cultivated spheres from the SW620 cell line in serum-free medium and evaluated the features of the spheres by immunofluorescence, cell cycle distribution, resistance to chemotherapeutics and soft agar clone formation, and the spheres were shown to be cancer stem-like cells through tumorigenicity in athymic nude mice. Reverse transcriptase polymerase chain reaction analysis of pluripotency genes, such as Sox-2, Oct-4 and Bmi-1, showed that the spheres were generated by dedifferentiation of SW620 cells. The study explored the use of n-3 polyunsaturated fatty acids (PUFAs) in spheres, which were treated with two n-3 PUFAs [docosahexaenoic acid (DHA)/eicosapentaenoic acid (EPA)]. Treatment of the spheres with DHA and EPA alone or in combination for 72 h led to apoptosis and the progressive loss of viability and DNA fragmentation and an increase in annexin V expression. DHA and EPA can enhance the chemotherapeutic sensitivity effect of 5-Fu and mitomycin C, especially DHA combined with EPA. Taken together, these results provide evidence that n-3 PUFAs exert a direct anticancer action that may contribute to their antiproliferative and proapoptotic effect on the cancer stem-like cells.

[Relationship between NQO1C(609T), RAD51(G135C), XRCC3(C241T) single nucleotide polymorphisms and acute lymphoblastic leukemia].

This study was purposed to investigate the relationship between NQO1C(609T), RAD51(G135C), XRCC3(C241T) single nucleotide polymorphisms and incidence of acute lymphoblastic leukemia (ALL). NQO1C(609T), RAD51(G135C), XRCC3(C241T) genotypes were detected by PCR-RFLP in 170 patients with de novo ALL and 458 normal persons as control. The results indicated that the genotype ratio of NQO1C(609T), RAD51(G135C) and XRCC3(C241T) in single genotype analysis showed no statistical difference between ALL patients and normal controls, which suggested that the single genotype affect onset of ALL without statistical significance. In combined genotype analysis, presence of both variants for NQO1C(609T) and RAD51(G135C) increased onset risk of ALL with myeloid antigen positive and with balanced translocation (OR value 5.553 and 2.618 respectively); the presence of homozygosity variant for NQO1C(609T) increased onset risk of ALL in the country-children (OR = 2.541). In conclusion, the combined effect of NQO1C(609T), RAD51(G135C) and XRCC3(C241T) genotypes may promote occurrence of ALL, which suggests that the combined analysis of 3 genotypes has more predictive significance for ALL than single genotype analysis.

[Clinical study on relationship between JAK2 V617F mutation and chronic myeloproliferative disorders].

OBJECTIVE: To investigate JAK2V617F mutation and its clinical significance in patients with chronic myeloproliferative disorders (cMPD). METHODS: A retrospective study was performed on 523 cMPD patients diagnosed according to the current World Health Organization (WHO) criteria. Allele-specific PCR (ASP) was used to identify JAK2V617F mutation, the mutation status was analyzed by PCR-RFLP, and the results were confirmed by sequence analysis. The mutation burden was calculated by the ratio of T/G. The correlation between the allele burden and the clinical and hematologic features was analysed. For those without JAK2 V617F, MPL W515L mutation was analyzed. RESULTS: JAK2 V617F was detected in 66% of all patients (94% in PV, 80% in ET, 78% in CIMF, 75% in CMPD-U and 14% in HES). The majority of patients carried JAK2 V617F mutation were heterozygous , homozygote was found in only 5 cases (4 in PV and 1 in ET). The mutation burden in most patients (71.5%) was low with PV>ET>CIMF (P =0.003). Hemoglobin level was significantly related to high mutation burden in PV (r = 0. 203, P =0.033). Bone marrow megakaryocyte counts were found to be marked increased in ET with high JAK2 V617F loads (P = 0.024), and hepatomegaly in CIMF was significantly associated with high JAK2 V617F mutation burden (r = 0.315, P = 0.001). CONCLUSIONS: 1) Most cMPD patients, especially those with PV, carry JAK2 V617F mutation, except for CML. 2) .98% of JAK2 V617F mutation occurs of heterozygous status. 3) The mutation burden is PV>FT>CIMF. High JAK2 V617F loads are significantly associated with higher hemoglobin level in PV and higher bone marrow megakaryocyte counts in ET. 4) The positive correlation between hepatomegaly and JAK2 V617F mutation burden is found in CIMF.

[Morphology and Immunophenotype Study of Bone Marrow Mononuclear Cells after Activated by Different Cytokines In Vitro]

Bone marrow cells in cultures were divided into four groups and cultured with various cytokines in vitro. These four groups are: control, IL-2 group, CD3-AK group, and CIK group. The morphological (cell volume, nucleus/plasm) changes of bone marrow cells in culture were observed. Immunophenotype analysis (CD34, CD38, CD3, CD56) were done before and after culture in all groups. Cytotoxicity against fresh acute leukemia cells were detected by modified MTT methods. The cell volume became larger with increased nucleus/plasm ratio in IL-2 group, CD3-AK group and CIK group. The plasm filled with PAS positive granules in most of cells in CD3-AK group and CIK group. The positive ratio of CD3, CD56, CD38 in CD3-AK or CIK group increased markedly after culture (P < 0.05), but no significant difference between the two groups. The CD56(+) cell increased in IL-2 group. CD34(+) cells decreased in all groups and there were no significant differences among those four groups. The cytotoxicity to fresh leukemia cells: CD3-AK group and CIK group > IL-2 group > control group. There was no significant difference between CD3-AK group and CIK group. This experiment showed different effect on bone marrow cells by different cytokine combination. The cytokine combination of CD3-AK group or CIK group can make immunocytes of bone marrow proliferating and retained certain amount of stem/progenitor cells.