C-MYC and Its Main Ubiquitin Ligase, FBXW7, Influence Cell Proliferation and Prognosis in Adult T-cell Leukemia/Lymphoma.

Smoldering-type and chronic-type adult T-cell leukemia/lymphomas (ATLL) patients have relatively indolent clinical courses, but often progress into aggressive lymphoma-type and acute-type disease. We examined the roles of transcription factor C-MYC and its ubiquitin ligase FBXW7 in tumor tissues from 137 patients with ATLL. Immunohistochemical tests showed ≥50% of lymphoma cells in 78.7% (48/61) of lymphoma-type, and 64.9% (24/37) of acute-type samples expressed C-MYC, significantly higher than was seen in smoldering-type (3.6%) and chronic-type (9.1%) samples (P<0.01). Real-time polymerase chain reaction showed C-MYC mRNA expression in lymphoma-type and acute-type samples were significantly higher than in smoldering-type (P<0.01). C-MYC expression was highly correlated with its mRNA levels (ρ=0.65, P<0.0001), chromosomal amplification and duplication (ρ=0.3, P=0.045) and MIB1 labeling index (ρ=0.69, P<0.0001). Expression of FBXW7 protein and mRNA in lymphoma-type samples were significantly lower than those of smoldering-type (P<0.01 for each), and both were inversely correlated with C-MYC (protein: ρ=-0.4, P=0.0002; mRNA: ρ=-0.31, P=0.015). Seven patients with smoldering-type or chronic-type ATLL converted to acute-type, in 4 of whom C-MYC expression increased from <50% to ≥50%. Patients with ≥50% C-MYC or MIB1 had significantly worse prognosis than those with <50% C-MYC (P=0.0004) or MIB1 (P<0.0001), as did those with ≥7.5 C-MYC mRNA scores (P=0.033); whereas significantly better prognosis was associated with ≥50% FBXW7 protein (P=0.0006) or ≥0.17 FBXW7 mRNA (P=0.016). C-MYC and FBXW7 affect ATLL proliferation and progression, and low FBXW7 may increase C-MYC expression. C-MYC was a critical prognostic factor in ATLL patients.

Molecular cytogenetic characterization of two established ESFT cell lines.

Ewing's sarcoma/primitive neuroectodermal tumor/Askin's tumor (Ewing`s sarcoma family of tumors: ESFT) is the most common type of malignant tumor of bone and soft tissue in children and young adults, and morphologically is a member of a group of small round cell tumors. We report, here, on the establishment of two human ESFT cell lines, FU-PNET-3 and FU-PNET-4, from the iliac and the chest wall, respectively, the cells of both cell lines were tumorigenic in immunodeficient mice. Histologically, both original and xenograft tumors and cultured cells were composed of small round cells with positive immunoreactivity for CD99 and Nkx2.2. Molecular biological examination demonstrated chimeric transcripts of EWSR1 exon 7 to FLI1 exon 6 in FU-PNET-3 cells, and EWSR1 exon 10 to FLI1 exon 6 in FU-PNET-4 cells. Cytogenetic analysis revealed chromosome translocation t(11;22)(q24;q12) and some secondary changes in both cultured cells. These histological, molecular biological, and cytogenetical findings indicate ESFT in both cell lines. ESFT is well studied, but its recurrent fusion genes are heterogeneous and its biological behaviors are unclear. The FU-PNET-3 and FU-PNET-4 cell lines have been well examined and may become useful tools for studying the genetic and biological behavioral properties of ESFT.

High Expression of Intestinal Homing Receptor CD103 in Adult T-Cell Leukemia/Lymphoma, Similar to 2 Other CD8+ T-Cell Lymphomas.

We investigated the expression of the αEß7 integrin (CD103)-intestinal homing receptor of T-intraepithelial lymphocytes (IELs) in 130 cases of adult T-cell leukemia/lymphoma (ATLL). We detected CD103 lymphoma cells in 55% (31/56) of mainly gastrointestinal (GI)-involved ATLL cases. Among them, lymphoma cells of 18 cases located in other involved organs had similar CD103 expression patterns. Histologically, we found (a) increased reactive IELs in non-neoplastic mucosal layers in 28% (5/18) of surgical and mucosal resection cases, (b) preserved epithelial glands, and (c) numerous small intraepithelial ATLL nests in involved lesions in 36 (69%) and 21 (40%), respectively, of the 52 examined cases. These 3 patterns were common in intestinal type II enteropathy-associated T-cell lymphoma but were rare in intestinal EBV nasal-type/like T/natural killer (NK)-cell lymphoma. We detected CD103 tumor cells in 41% (16/39) of lymph node-involved ATLL, in 31% (11/35) of skin-involved ATLL, in 68% (21/31) of type II CD4 enteropathy-associated T-cell lymphoma cases, in 36% (8/22) of primary gastric T/NK-cell lymphomas, and in 77% (7/9) of CD8 epidermotropic mycosis fungoides. CD103 ATLL prefers involving the GI tract over the skin (P<0.05). CD103 expression in GI-involved and/or total ATLL cases was significantly higher than in other 9 T/NK-cell lymphoma groups (P<0.05 or 0.01). Only ATLL cases were commonly CD103 in CD4 T/NK-cell lymphoma groups (P<0.05 or 0.01). Human T-lymphotropic virus-1-infected CD103 T-IELs and mucosal T cells may be important sources of ATLL.

Early colorectal carcinomas: CD10 expression, mucin phenotype and submucosal invasion.

We analyzed 170 tumors (polypoid, 98; non-polypoid, 72) of early colorectal carcinoma with or without submucosal invasions (Tis and T1 of TNM classification) from 161 patients to evaluate correlations between clinicopathological factors and immunohistochemical expressions of CD10, MUC2, and MUC5AC. The coexistence of adenomatous components was significantly less common in non-polypoid carcinomas (4.2%) than in polypoid carcinomas (66.3%) (P < 0.0001). Non-polypoid carcinomas were smaller in size and tended to infiltrate into the submucosa with higher incidence of lymphatic and venous permeations. CD10 was more frequently expressed in non-polypoid carcinomas (70.8%) than in polypoid carcinomas (51.0%) (P= 0.01). Total carcinomas with high grade atypia showed higher incidence of CD10 expression (60.6%) than those with low grade atypia (28.9%) (P < 0.0001). Carcinomas with low grade atypia exhibited a higher incidence of MUC2 and MUC5AC expression (91.1% and 57.8%, respectively), when compared with carcinomas with high grade atypia (41.6% and 20.0%, respectively) (both, P < 0.0001). In submucosal invasive carcinomas with residual intramucosal carcinoma component (IMCC), CD10 expression in IMCC and submucosal invasive carcinoma component (SMCC) simultaneously exhibited identical positive or negative results, regardless of the polypoid or non-polypoid growth pattern. The CD10 expression may occur in the early stage of carcinogenesis within the mucosa, and these neoplasms may retain CD10 in SMCC, possibly resulting in more advanced stages of stromal invasion and distant metastases. In conclusion, our data suggest that the CD10 expression and mucin phenotypes may be potentially useful markers for estimating biological properties of early colorectal carcinomas.