OBJECTIVETo study the effects of antisense oligonucleotide (ASODN) targeting ST6Gal I on cell adhesion and invasiveness of human cervical carcinoma cell line HeLa which over-expressed ST6Gal I .

METHODSASODN and sense oligonucleotide (SODN) targeting ST6Gal I were designed and constructed, and transfected into a cervical cancer cell line, HeLa, by lipofectmine 2000. HeLa cells were cultured and divided into 4 groups: blank control group, liposome group, SODN group and ASODN group. RT-PCR was used to examine the ST6Gal I mRNA expression. Flow cytometry was used to examine the amount of alpha2, 6-sialylation on the HeLa cell surface. The HeLa cell adhesion and invasiveness to extracellular matrix ( ECM) were analyzed by using CytoMatrixTM kit and cell invasion assay kit, respectively.

RESULTSThe expression of ST6Gal I mRNA in HeLa cells at 48 hrs after transfection in the ASODN group was significantly decreased in comparison with that in the blank control group, liposome group, and SODN group(P <0. 01). The amount of alpha2,6-sialylation on cell surface in ASODN group was significantly lower than that of the other 3 groups ( P <0. 05). The adhesion and invasiveness of the cells in the ASODN group decreased remarkably, both significantly lower than those of the other 3 groups ( all P < 0. 05).

CONCLUSIONSpecific ASODN targeting ST6Gal I effectively inhibits HeLa cell ST6Gal I expression, decreases the amount of alpha2,6-sialylation on cell surface and leads to a decline of cell adhesion and invasiveness to ECM. This result also established a fine base for further studying on anti-tumor treatment with antisense oligonucleotide.

Cell Adhesion ; genetics ; physiology ; Cell Movement ; genetics ; physiology ; Flow Cytometry ; Gene Silencing ; HeLa Cells ; Humans ; Neoplasm Invasiveness ; Oligodeoxyribonucleotides, Antisense ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Sialyltransferases ; biosynthesis ; genetics ; Transfection

In this study, we have shown that gene expression of human GD3 synthase (hST8Sia I) is suppressed by triptolide (TPL) in human melanoma SK-MEL-2 cells. To elucidate the mechanism underlying the downregulation of hST8Sia I gene expression in TPL-treated SK-MEL-2 cells, we characterized the TPL-inducible promoter region within the hST8Sia I gene using luciferase constructs carrying 5'-deletions of the hST8Sia I promoter. Functional analysis of the 5'-flanking region of the hST8Sia I gene demonstrated that the -1146 to -646 region, which contains putative binding sites for transcription factors c-Ets-1, CREB, AP-1 and NF-kappaB, functions as the TPL-inducible promoter of hST8Sia I in SK-MEL-2 cells. Site-directed mutagenesis and ChIP analysis indicated that the NF-kappaB binding site at -731 to -722 is crucial for TPL-induced suppression of hST8Sia I in SK-MEL-2 cells. This suggests that TPL induces down-regulation of hST8Sia I gene expression through NF-kappaB activation in human melanoma cells.
Cell Proliferation/drug effects ; Diterpenes/*pharmacology ; Down-Regulation ; Epoxy Compounds/pharmacology ; Genes, Reporter ; Humans ; NF-kappa B/metabolism ; Phenanthrenes/*pharmacology ; Promoter Regions, Genetic ; Sialyltransferases/*biosynthesis/genetics ; Tumor Cells, Cultured

In order to compare the prognoses of patients with diffuse malignant lymphomas on the basis of histology and immunophenotypes, we retrospectively studied 62 cases of diffuse lymphoma arising in lymph nodes. We also evaluated the reactivity patterns of monoclonal antibodies (MoAb) LN1, LN2 and LN3 to determine the criteria for making a differential diagnosis in B cell lymphomas. The immunologic phenotypes were determined by the avidin biotin peroxidase complex method, using frozen or paraffin fixed tissues. The majority (66.3%) were B cell with the remaining 20.9% being T cell and 12.9% were non-B, non-T cell lineage. Immunological heterogeneity was found especially in the mixed small and large cell and the immunoblastic lymphomas. There was no significant difference between B- and T-cell lymphomas with respect to survival and death (P > 0.05). Histologically 79% (49/62) of the lymphoma was large cell and 21% (13/62), small cell lymphoma. There was a difference in prognosis between low, intermediate and high-grade of lymphomas. However there were no significant differences among the subtypes of the diffuse aggressive lymphomas. Factors associated with poor prognosis were advanced stages (P < 0.025) and histology of the malignant lymphomas. MoAb LN1, LN2 and LN3 gave positive staining in 83.3%, 91.7% and 60% of B cell lymphomas, respectively. The most common phenotypic pattern in B cell lymphomas was LN1+, LN2+, LN3+/-, suggestive of follicular center cell origin. As a panel, phenotypic patterns of MoAb LN1, LN2 and LN3 may be useful in differentiation of follicular center cell lymphoma from others.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Antigens, CD/biosynthesis ; Antigens, Differentiation, B-Lymphocyte/biosynthesis ; Child ; Female ; Follow-Up Studies ; Histocompatibility Antigens Class II/biosynthesis ; Humans ; Immunoenzyme Techniques ; Immunophenotyping ; Lymphoma, B-Cell/immunology ; Lymphoma, Non-Hodgkin/immunology/*pathology ; Male ; Middle Aged ; Neoplasm Staging ; Prognosis ; Sialyltransferases/biosynthesis