Normal and cancer fibroblasts differentially regulate TWIST1, TOX and cytokine gene expression in cutaneous T-cell lymphoma

Abstract

Background Mycosis fungoides (MF) is a primary cutaneous T-cell lymphoma (CTCL) that transforms from mature, skin-homing T cells and progresses during the early stages in the skin. The role of the skin microenvironment in MF development is unclear, but recent findings in a variety of cancers have highlighted the role of stromal fibroblasts in promoting or inhibiting tumorigenesis. Stromal fibroblasts are an important part of the cutaneous tumor microenvironment (TME) in MF. Here we describe studies into the interaction of TME-fibroblasts and malignant T cells to gain insight into their role in CTCL. Methods Skin from normal (n = 3) and MF patients (n = 3) were analyzed for FAPα by immunohistochemistry. MyLa is a CTCL cell line that retains expression of biomarkers TWIST1 and TOX that are frequently detected in CTCL patients. MyLa cells were cultured in the presence or absence of normal or MF skin derived fibroblasts for 5 days, trypsinized to detached MyL a cells, and gene expression analyzed by RT-PCR for MF biomarkers (TWIST1 and TOX), Th1 markers (IFNG, TBX21), Th2 markers (GATA3, IL16), and proliferation marker (MKI67). Purified fibroblasts were assayed for VIM and ACTA2 gene expression. Cellular senescence assay was performed to assess senescence. Results MF skin fibroblast showed increased expression of FAP-α with increasing stage compared to normal. Normal fibroblasts co-cultured with MyLa cells suppressed expression of TWIST1 (p < 0.0006), and TOX (p < 0.03), GATA3 (p < 0.02) and IL16 (p < 0.03), and increased expression of IFNG (p < 0.03) and TBX21 (p < 0.03) in MyLa cells. In contrast, MyLa cells cultured with MF fibroblasts retained high expression of TWIST1, TOX and GATA3. MF fibroblasts co-culture with MyLa cells increased expression of IL16 (p < 0.01) and IL4 (p < 0.02), and suppressed IFNG and TBX21 in MyLa cells. Furthermore, expression of MKI67 in MyLa cells was suppressed by normal fibroblasts compared to MF fibroblasts. Conclusion Skin fibroblasts represent important components of the TME in MF. In co-culture model, normal and MF fibroblasts have differential influence on T-cell phenotype in modulating expression of Th1 cytokine and CTCL biomarker genes to reveal distinct roles with implications in MF progression.

TOX Expression in Mycosis Fungoides and Sezary Syndrome

“…Furthermore, Morimura et al [44] described an increase of the marker levels as the disease progressed, a finding also observed in our cases. Indeed, in our analysis, the increase in TOX expression in advance-phase disease as well as the higher TOX expression in A+ and DOD patients when compared to A− ones corroborate the hypothesis that TOX may be regarded more as a prognostic than as a diagnostic marker [6,8,51,52]. Such evidence may be emphasized by the decrease in TOX levels in two patients (no 14 and 18) who had a relapse in early-stage patch after TSEBI+bexarotene treatment with a decreased expression in TOX levels.…”

Cancer Progression Mediated by CAFs Relating to HCC and Identification of Genetic Characteristics Influencing Prognosis

“…In the present study, five genes have been obtained for the HCC prognostic model. ACTA2 , actin alpha 2, which contributed to cell-generated mechanical tension and maintenance of cell shape and movement, was highly expressed in carcinomas [ 24 ]. Meanwhile, a previous study showed that CAFs enhanced the tumor-initiating and tumorigenic properties of HCC cells, and ACTA2 was exactly a biomarker of CAFs.…”

Stromal Factors as a Target for Immunotherapy in Melanoma and Non-Melanoma Skin Cancers

“…The tumor-derived exosome, shuttle miR-375, polarized CAFs into aSMA, CXCL2, and IL-1b-expressing phenotypes, promoting tumor growth by decreasing p53 pathway-related gene expression in Merkel cell carcinoma [ 103 ]. In mycosis fungoides, CAFs derived from mycosis fungoides increased the expression of GATA3 (Th2 marker), as well as TWIFT1 and TOX (also used as a biomarker gene for the progression of mycosis fungoides), in CTCL cells [ 104 ] Overall, these reports suggest the possible mechanisms of crosstalk between tumor cells and CAFs in the development of the tumor microenvironment in non-melanoma skin cancers.…”