Outcome of allogeneic hematopoietic stem cell transplantation for mycosis fungoides and Sézary syndrome

Although allogeneic hematopoietic stem cell transplantation (HSCT) has been reported to provide prolonged remission of relapsed/refractory mycosis fungoides (MF) and Sézary syndrome (SS), its role has not been fully evaluated. Here, the outcomes of allogeneic HSCT for patients with MF/SS were retrospectively evaluated by using the registry database of the Japan Society for Hematopoietic Cell Transplantation. Forty-eight patients were evaluable and enrolled in the analysis. Median age was 45.5 years. Eighteen patients (38%) received myeloablative conditioning, and 33 (69%) received HSCT from an alternative donor. Disease status was complete or partial response in 25% of the patients and relapsed or refractory in the others. At the time of analysis, 18 patients were alive, with a median follow-up of 31.0 months (range, 3.8-31.1). Three-year overall survival (OS) and progression-free survival (PFS) were 30% (95%CI, 16-45%) and 19% (95%CI, 9-31%), respectively. Disease progression was not observed later than 17 months after transplantation. Both disease status and performance status at transplant significantly affected OS and PFS. Although our findings suggest that allogeneic HSCT provides long-term PFS in patients with MF/SS, the timing of transplantation should be decided carefully based on the disease status and the patient's condition in order to improve the outcome.     

Stratification of HPV-associated and HPV-negative oropharyngeal squamous cell carcinomas based on DNA methylation epigenotypes

While the incidence of oropharyngeal squamous cell carcinoma (OPSCC) has been increasing in these two decades, primarily due to human papillomavirus (HPV), stratification of OPSCC into molecular subgroups showing different clinicopathological features has not been fully investigated. We performed DNA methylome analysis using Infinium 450k for 170 OPSCC cases, including 89 cases in our cohort and 81 cases reported by The Cancer Genome Atlas, together with targeted exon sequencing analysis. We stratified OPSCC by hierarchical clustering analysis using methylome data. Methylation levels of classifier markers were validated quantitatively using pyrosequencing, and area under the curve (AUC) values of receiver operating characteristics (ROC) curves were calculated. OPSCC was stratified into four epigenotypes: HPV(+) high-methylation (OP1), HPV(+) intermediate-methylation (OP2), HPV(−) intermediate-methylation (OP3) and HPV(−) low-methylation (OP4). Ten methylation marker genes were generated: five to classify HPV(+) cases into OP1 and OP2, and five to classify HPV(−) cases into OP3 and OP4. AUC values of ROC curves were 0.969 and 0.952 for the two marker panels, respectively. While significantly higher TP53 mutation and CCND1 copy number gains were observed in HPV(−) than in HPV(+) groups (p < 0.01), no significant difference of genomic aberrations was observed between OP1 and OP2, or OP3 and OP4. The four epigenotypes showed significantly different prognosis (p = 0.0006), distinguishing the most favorable OPSCC subgroup (OP1) among generally favorable HPV(+) cases, and the most unfavorable OPSCC subgroup (OP3) among generally unfavorable HPV(−) cases. HPV(+) and HPV(−) OPSCC are further divided into distinct DNA methylation epigenotypes, showing significantly different prognosis.     

Repair of DNA damage induced by the novel nucleoside analogue CNDAG through homologous recombination

We postulate that the deoxyguanosine analogue CNDAG [9-(2-C-cyano-2-deoxy-1-β-d-arabino-pentofuranosyl)guanine] likely causes a single-strand break after incorporation into DNA, similar to the action of its cytosine congener CNDAC, and that subsequent DNA replication across the unrepaired nick would generate a double-strand break. This study aimed at identifying cellular responses and repair mechanisms for CNDAG prodrugs, 2-amino-9-(2-C-cyano-2-deoxy-1-β-d-arabino-pentofuranosyl)-6-methoxy purine (6-OMe) and 9-(2-C-cyano-2-deoxy-1-β-d-arabino-pentofuranosyl)-2,6-diaminopurine (6-NH2). Each compound is a substrate for adenosine deaminase, the action of which generates CNDAG. Growth inhibition assay, clonogenic survival assay, immunoblotting, and cytogenetic analyses (chromosomal aberrations and sister chromatid exchanges) were used to investigate the impact of CNDAG on cell lines. The 6-NH2 derivative was selectively potent in T cell malignant cell lines. Both prodrugs caused increased phosphorylation of ATM and its downstream substrates Chk1, Chk2, SMC1, NBS1, and H2AX, indicating activation of ATM-dependent DNA damage response pathways. In contrast, there was no increase in phosphorylation of DNA-PKcs, which participates in repair of double-strand breaks by non-homologous end-joining. Deficiency in ATM, RAD51D, XRCC3, BRCA2, and XPF, but not DNA-PK or p53, conferred significant clonogenic sensitivity to CNDAG or the prodrugs. Moreover, hamster cells lacking XPF acquired remarkably more chromosomal aberrations after incubation for two cell cycle times with CNDAG 6-NH2, compared to the wild type. Furthermore, CNDAG 6-NH2 induced greater levels of sister chromatid exchanges in wild-type cells exposed for two cycles than those for one cycle, consistent with increased double-strand breaks after a second S phase. CNDAG-induced double-strand breaks are repaired mainly through homologous recombination.     

Effects of α1-adrenergic receptor antagonists on the development and progression of urothelial cancer

We recently demonstrated that silodosin, a selective α₁-blocker often prescribed for the symptomatic treatment of benign prostatic hyperplasia (BPH), could inactivate a c-fos proto-oncogene regulator ELK1 in bladder cancer cells possessing a functional androgen receptor (AR). However, the clinical impact of α₁-blockers on the development and progression of bladder cancer remained poorly understood. In the present study, we investigated if α₁-blockers clinically used, including silodosin, tamsulosin, and naftopidil, could prevent the neoplastic/malignant transformation and cell growth, using non-neoplastic urothelial SVHUC sublines with carcinogen/MCA challenge and bladder cancer lines, respectively. Bladder cancers in men treated with silodosin, tamsulosin, or naftopidil for their BPH were then compared. Silodosin at 1-10 µM significantly inhibited the neoplastic transformation of MCA-SVHUC-AR cells, but not that of AR-negative MCA-SVHUC-control cells. In MCA-SVHUC-AR, silodosin significantly reduced the expression levels of oncogenes (c-fos/NF-κB1) and induced those of tumor suppressors (p27/PTEN). However, tamsulosin (up to 1 µM) or naftopidil (up to 10 µM) failed to significantly inhibit the neoplastic transformation of AR-positive or AR-negative urothelial cells. Similarly, cell proliferation/migration of AR-positive bladder cancer lines was considerably inhibited only by silodosin. Meanwhile, the incidence of bladder cancer in patients with silodosin [49/540 (9.1%)] was marginally lower, compared to those with tamsulosin [64/523 (12.2%); P=0.094] or tamsulosin or naftopidil [64+28/523+236 (12.1%); P=0.082]. There were no significant differences in tumor grade/stage among the 3 cohorts. Outcome analysis revealed lower risks for disease progression of non-muscle-invasive bladder tumors in the silodosin group than in the naftopidil group (P=0.011) or tamsulosin+naftopidil groups (P=0.035). Similarly, silodosin patients with muscle-invasive tumor had lower risks for disease progression, compared with tamsulosin (P=0.006) or tamsulosin+naftopidil (P=0.028) patients. Multivariate analysis further showed that silodosin treatment in those with non-muscle-invasive tumor was associated with improved progression-free survival, compared with naftopidil (hazard ratio=0.086; 95% confidence interval=0.008-0.905; P=0.041) or tamsulosin/naftopidil (hazard ratio=0.128; 95% confidence interval=0.016-1.036; P=0.054) treatment. Our in vitro studies thus indicate that both urothelial tumorigenesis and tumor growth are inhibited by silodosin, but not by tamsulosin or naftopidil. Clinical data further suggest that even pharmacological doses (e.g. 0.1 µM) of silodosin contribute to preventing bladder cancer progression.     

CT evaluation of paraaortic lymph node metastasis in patients with biliary cancer

Background The extent of paraaortic lymph node (PAN) metastasis parellels that of distant metastases in patients with biliary carcinoma. Accurate preoperative assessment of PAN metastasis has a crucial impact on surgical indications. In this retrospective study, we evaluated whether computed tomography (CT) scans were useful for diagnosing PAN metastases and excluding patients with PAN metastases from an indication for surgery.Methods Between March 1999 and November 2003, 57 patients with biliary carcinoma underwent radical lymphadenectomy or surgical biopsy of PANs. Nine of these patients were diagnosed as having PAN metastasis microscopically. All patients had undergone abdominal CT scans before surgery. To diagnose PAN metastases, we used the following diagnostic criteria. (1) Size; when lymph nodes were greater than 12 mm, 10 mm, 8 mm, or 6 mm in longo or short-axis diameter, the nodes were considered metastatic. (2) Shape and size; when the axial ratio of a lymph node was greater than 0.5, 0.7, 1.0, and the maximum diameter of the long or short axis was greater than 12 mm, 10 mm, 8 mm, or 6 mm, the node was considered metastatic. (3) Internal structure; if the internal structure of a PAN was heterogeneous, the node was considered metastatic. A positive predictive value was calculated for each included criterion when patients numbered ten or more.Results Positive predictive values using the above criteria ranged from 13% to 36%. Only one patient had PANs with heterogeneous internal structures.Conclusions We were unable to determine surgical indications based on the morphological criteria revealed by a CT scan.