AIM: To investigate the expression of SNC73, a transcript of the immunoglobulin α-1 gene (IgA1-H chain), in human epitheliα-derived tumor cells. METHODS: Total RNAs and cell lysates were prepared from five diffe...AIM: To investigate the expression of SNC73, a transcript of the immunoglobulin α-1 gene (IgA1-H chain), in human epitheliα-derived tumor cells. METHODS: Total RNAs and cell lysates were prepared from five different human epithelial cell lines derived from lung, stomach, liver, skin, and breast, respectively. RT-PCR and immunoblot analysis of these five cell lines were done. Both RT-PCR and immunochemistry were used to detect the expression of SNC73 in these cell lines. We also examined the expression of SNC73 in normal epithelial cells of colon mucosa by in situ hybridization. RT-PCR and immunoblot analysis were used to determine whether the recombination activating gene1/2 (RAG1 and RAG2) is present. The expression of three immunoglobulin transcription factors, EBF, E2A and Pax5, and the heavy chain of IgA1 and two types of light chains of immunoglobulin (κ and λ) in the aforementioned cell lines were analyzed by RT-PCR and immunochemistry, respectively. All the RT-PCR products were analyzed by sequencing. RESULTS: The results of RT-PCR and immunochemistry showed that both mRNA and protein of SNC73 were expressed in five human epitheliα-derived cancer cell lines. These data were further confirmed in the normal epithelial cells of colon mucosa by in situ hybridization. Also, the heavy chain of IgA1 and κ light chain were detected in these cells, but no λ light chain was observed. Both RAG1 and RAG2 were expressed in these human epitheliα-derived cancer cell lines and the sequence was identical to that expressed in pre-B and pre-T cells. In addition to RAG1 and RAG2, the mRNA in one of the immunoglobulin transcription factors, EBF, was also detected in these cell lines, and Pax5 was only expressed in SW480 cells, but no expression of E2A was observed in all the five cell lines. CONCLUSION: Immunoglobulin A1 is originally expressed and V(D)J recombination machine is also present in non-lymphoid cells, suggesting that V(D)J recombination machine mediates the assembly of immunoglo展开更多
Inhibitory leukocyte immunoglobulin-like receptors(LILRB1-5) signal through immunoreceptor tyrosine-based inhibitory motifs(ITIMs) in their intracellular domains and recruit phosphatases protein tyrosine phosphatase, ...Inhibitory leukocyte immunoglobulin-like receptors(LILRB1-5) signal through immunoreceptor tyrosine-based inhibitory motifs(ITIMs) in their intracellular domains and recruit phosphatases protein tyrosine phosphatase, non-receptor type 6(PTPN6, SHP-1), protein tyrosine phosphatase, non-receptor type 6(PTPN6, SHP-2), or Src homology 2 domain containing inositol phosphatase(SHIP) to negatively regulate immune cell activation. These receptors are known to play important regulatory roles in immune and neuronal functions. Recent studies demonstrated that several of these receptors are expressed by cancer cells. Importantly, they may directly regulate development, drug resistance, and relapse of cancer, and the activity of cancer stem cells. Although counterintuitive, these findings are consistent with the generally immune-suppressive and thus tumor-promoting roles of the inhibitory receptors in the immune system. This review focuses on the ligands, expression pattern, signaling, and function of LILRB family in the context of cancer development. Because inhibition of the signaling of certain LILRBs directly blocks cancer growth and stimulates immunity that may suppress tumorigenesis, but does not disturb normal development, LILRB signaling pathways may represent ideal targets for treating hematological malignancies and perhaps other tumors.展开更多
文摘AIM: To investigate the expression of SNC73, a transcript of the immunoglobulin α-1 gene (IgA1-H chain), in human epitheliα-derived tumor cells. METHODS: Total RNAs and cell lysates were prepared from five different human epithelial cell lines derived from lung, stomach, liver, skin, and breast, respectively. RT-PCR and immunoblot analysis of these five cell lines were done. Both RT-PCR and immunochemistry were used to detect the expression of SNC73 in these cell lines. We also examined the expression of SNC73 in normal epithelial cells of colon mucosa by in situ hybridization. RT-PCR and immunoblot analysis were used to determine whether the recombination activating gene1/2 (RAG1 and RAG2) is present. The expression of three immunoglobulin transcription factors, EBF, E2A and Pax5, and the heavy chain of IgA1 and two types of light chains of immunoglobulin (κ and λ) in the aforementioned cell lines were analyzed by RT-PCR and immunochemistry, respectively. All the RT-PCR products were analyzed by sequencing. RESULTS: The results of RT-PCR and immunochemistry showed that both mRNA and protein of SNC73 were expressed in five human epitheliα-derived cancer cell lines. These data were further confirmed in the normal epithelial cells of colon mucosa by in situ hybridization. Also, the heavy chain of IgA1 and κ light chain were detected in these cells, but no λ light chain was observed. Both RAG1 and RAG2 were expressed in these human epitheliα-derived cancer cell lines and the sequence was identical to that expressed in pre-B and pre-T cells. In addition to RAG1 and RAG2, the mRNA in one of the immunoglobulin transcription factors, EBF, was also detected in these cell lines, and Pax5 was only expressed in SW480 cells, but no expression of E2A was observed in all the five cell lines. CONCLUSION: Immunoglobulin A1 is originally expressed and V(D)J recombination machine is also present in non-lymphoid cells, suggesting that V(D)J recombination machine mediates the assembly of immunoglo
基金supported b y the Na tional In stitu te o f Health(1R01CA172268)the Leukemia&Lymphoma Society(1024-14+7 种基金TRP-6024-14)the Robert A.Welch Foundation(I-1834)the Cancer Prevention and Research Institute of Texas(RP140402 and DP150056)the Innovation Program of Shanghai Municipal Education Commission(13G20)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learningthe National Natural Science Foundation of China(813706548142200181471524)
文摘Inhibitory leukocyte immunoglobulin-like receptors(LILRB1-5) signal through immunoreceptor tyrosine-based inhibitory motifs(ITIMs) in their intracellular domains and recruit phosphatases protein tyrosine phosphatase, non-receptor type 6(PTPN6, SHP-1), protein tyrosine phosphatase, non-receptor type 6(PTPN6, SHP-2), or Src homology 2 domain containing inositol phosphatase(SHIP) to negatively regulate immune cell activation. These receptors are known to play important regulatory roles in immune and neuronal functions. Recent studies demonstrated that several of these receptors are expressed by cancer cells. Importantly, they may directly regulate development, drug resistance, and relapse of cancer, and the activity of cancer stem cells. Although counterintuitive, these findings are consistent with the generally immune-suppressive and thus tumor-promoting roles of the inhibitory receptors in the immune system. This review focuses on the ligands, expression pattern, signaling, and function of LILRB family in the context of cancer development. Because inhibition of the signaling of certain LILRBs directly blocks cancer growth and stimulates immunity that may suppress tumorigenesis, but does not disturb normal development, LILRB signaling pathways may represent ideal targets for treating hematological malignancies and perhaps other tumors.