RESUMEN
Esophageal cancer is a deadly disease, ranking sixth among all cancers in mortality. Despite incremental advances in diagnostics and therapeutics, esophageal cancer still carries a poor prognosis, and thus, there remains a need to elucidate the molecular mechanisms underlying this disease. There is accumulating evidence that a comprehensive understanding of the molecular composition of esophageal cancer requires attention to not only tumor cells but also the tumor microenvironment (TME), which contains diverse cell populations, signaling factors and structural molecules that interact with tumor cells and support all stages of tumorigenesis. In esophageal cancer, environmental exposures can trigger chronic inflammation, which leads to constitutive activation of pro-inflammatory signaling pathways that promote survival and proliferation. Antitumor immunity is attenuated by cell populations such as myeloid-derived suppressor cells and regulatory T cells, as well as immune checkpoints like programmed death-1. Other immune cells such as tumor-associated macrophages can have other pro-tumorigenic functions, including the induction of angiogenesis and tumor cell invasion. Cancer-associated fibroblasts secrete growth factors and alter the extracellular matrix to create a tumor niche and enhance tumor cell migration and metastasis. Further study of how these TME components relate to the different stages of tumor progression in each esophageal cancer subtype will lead to development of novel and specific TME-targeting therapeutic strategies, which offer considerable potential especially in the setting of combination therapy.
Asunto(s)
Neoplasias Esofágicas/genética , Inflamación/genética , Neovascularización Patológica/genética , Microambiente Tumoral/genética , Apoptosis/genética , Apoptosis/inmunología , Puntos de Control del Ciclo Celular/genética , Puntos de Control del Ciclo Celular/inmunología , Neoplasias Esofágicas/patología , Humanos , Inflamación/inmunología , Inflamación/patología , Invasividad Neoplásica/inmunología , Neovascularización Patológica/patología , Linfocitos T Reguladores/inmunologíaRESUMEN
Earlier we have shown high frequency of loss of heterozygosity of microsatellite marker D6S273 within HLA III class region in DNA samples from cervical intraepithelial neoplasias and cervical cancer. According to publications three genes were identified in this region. For detection of D6S273 position we used in silico analysis of mRNA sequences deposited in GenBank (NCBI) and investigated LY6G6D gene expression in tumor cell lines. LY6G6D gene exon borders were analyzed with 5'- or 3'-rapid amplification of cDNA ends. We have found that LY6G6D gene consists of 9 exons and includes two earlier identified genes G6D and G6F. Microsatellite D6S273 is located in the last 8 intron of LY6G6D gene. The third gene LY6G6E consisting of four exons is located in 6 intron of LY6G6D gene in the opposite orientation. We suggest that LY6G6D gene is coding three main mRNA transcripts in the same open reading frame but differ in exon composition: MEGT1 consists of 1-4, 8, 9 exons, G6F consists of 1-6 exons and G6D consists of 7-9 exons of LY6G6D gene. High homology with immunoglobulin superfamily within 20-120 aminoacids of MEGT1 and G6F proteins is shown by in silico translation of their mRNAs.