We show that the times separating the birth of benign, invasive, and metastatic tumor cells can be determined by analysis of the mutations they have in common. When combined with prior clinical observations, these analyses suggest the following general conclusions about colorectal tumorigenesis: (i) It takes Ϸ17 years for a large benign tumor to evolve into an advanced cancer but <2 years for cells within that cancer to acquire the ability to metastasize; (ii) it requires few, if any, selective events to transform a highly invasive cancer cell into one with the capacity to metastasize; (iii) the process of cell culture ex vivo does not introduce new clonal mutations into colorectal tumor cell populations; and (iv) the rates at which point mutations develop in advanced cancers are similar to those of normal cells. These results have important implications for understanding human tumor pathogenesis, particularly those associated with metastasis.cancer genetics ͉ colorectal cancer ͉ metastasis ͉ stem cells

Long non-coding RNAs (lncRNAs) play critical roles in diverse cellular processes; however, their involvement in many critical aspects of the immune response including the interferon (IFN) response remains poorly understood. To address this gap, we compared the global gene expression pattern of primary human hepatocytes before and at three time points after treatment with IFN-α. Among ∼200 IFN-induced lncRNAs, one transcript showed ∼100-fold induction. This RNA, which we named lncRNA-CMPK2, was a spliced, polyadenylated nuclear transcript that was induced by IFN in diverse cell types from human and mouse. Similar to protein-coding IFN-stimulated genes (ISGs), its induction was dependent on JAK-STAT signaling. Intriguingly, knockdown of lncRNA-CMPK2 resulted in a marked reduction in HCV replication in IFN-stimulated hepatocytes, suggesting that it could affect the antiviral role of IFN. We could show that lncRNA-CMPK2 knockdown resulted in upregulation of several protein-coding antiviral ISGs. The observed upregulation was caused by an increase in both basal and IFN-stimulated transcription, consistent with loss of transcriptional inhibition in knockdown cells. These results indicate that the IFN response involves a lncRNA-mediated negative regulatory mechanism. lncRNA-CMPK2 was strongly upregulated in a subset of HCV-infected human livers, suggesting a role in modulation of the IFN response in vivo.

Mycophenolate mofetil (MMF) and sirolimus impair wound healing. We compared sirolimus vs. MMF to determine the relative impact on surgical complications and wound healing in adult kidney transplant recipients. This retrospective, single center study of 235 adult kidney transplants performed between 1 January 2000 and 31 January 2002 identified 158 adult, kidney‐only recipients treated with tacrolimus and prednisone, from which two groups were defined: group 1 (n = 84) received MMF, group 2 (n = 74) received sirolimus. The incidence of fluid collections, wound problems, dehiscence, and urine leak were compared. A multivariate stepwise logistical regression analysis was performed to identify risk factors. The overall incidence of complications was 21.5%, with rates significantly lower in group 1 (2.4%) vs. group 2 (43.2%, p < 0.0001). Regression analysis showed only sirolimus (p < 0.001) and hypo‐albuminemia (p = 0.006) to independently correlate with complication occurrence. In subanalyses, lymphoceles correlated only with sirolimus (p = 0.003), while other wound problems also correlated with higher body mass index (p = 0.067). The use of sirolimus, tacrolimus and prednisone was associated with a greater incidence of lymphoceles, non‐lymphocele perinephric fluid collections and other consequences of poor wound healing, as compared to contemporary patients treated with MMF, tacrolimus and prednisone.

Mice immunized against a cancer recognize antigens unique to that cancer, but the molecular structures of such antigens are unknown. We isolated CD4+ T cell clones recognizing an antigen uniquely expressed on the UV-induced tumor 6132A; some clones inhibited the growth of tumors bearing the specific antigen. A T cell hybridoma was used to purify this antigen from nuclear extracts by RP-HPLC and SDS-PAGE using T cell immunoblot assays. A partial amino acid sequence was nearly identical to a sequence in ribosomal protein L9. The cDNA sequence of L9 from 6132A PRO cells differed from the normal sequence at one nucleotide; this mutation encoded histidine instead of leucine at position 47. A synthetic peptide containing this mutation was over 1000-fold more stimulatory of T cells than was the wild-type peptide. These results indicate that this unique tumor antigen is derived from a single amino acid substitution in a cellular protein.

ObjectiveA review of 100 living-liver donors was performed to evaluate the perisurgical complications of the procedure and thus to help quantify the risks to the donor. Summary Background DataDespite the advantages of living-donor liver transplantation (LDLT), the procedure has received criticism for the risk it imposes on healthy persons. A paucity of data exists regarding the complications and relative safety of the procedure. MethodsOne hundred LDLTs performed between November 1989 and November 1996 were reviewed. Donor data were obtained by chart review, anesthesia records, and the computerized hospital data base. Patient variables were compared by Fisher's exact test and the Student's t test. ResultsThere were 57 women and 43 men with a median age of 29. Donors were divided into two groups: group A (first 50 donors), and group B (last 50 donors). There were 91 left lateral segments and 9 left lobes. There were no deaths. Fourteen major complications occurred in 13 patients; 9 occurred in group A and 5 in group B. Biliary complications consisted of five bile duct injuries (group A = 4, group B = 1) and two cut edge bile leaks. Complications were more common in left lobe resections (55%) than in left lateral segment grafts (10%). Minor complications occurred in 20% of patients. A significant reduction in overall complications (major and minor) was observed between the groups (group A, n = 24 [45%] vs. group B, n = 10 [20%]). In addition, surgical time and hospital stay were both significantly reduced. ConclusionsAlthough the procedure is safe, many LDLT donors have a perisurgical complication. Surgical experience and technical modifications have resulted in a significant reduction in these complications, however. To minimize the risks for these healthy donors, LDLT should be performed at institutions with extensive experience.