Genetic drivers of oncogenic pathways in molecular subgroups of peripheral T-cell lymphoma.

Peripheral T-cell lymphoma (PTCL) is a group of complex clinicopathological entities, often associated with an aggressive clinical course. Angioimmunoblastic T-cell lymphoma (AITL) and PTCL-not otherwise specified (PTCL-NOS) are the 2 most frequent categories, accounting for >50% of PTCLs. Gene expression profiling (GEP) defined molecular signatures for AITL and delineated biological and prognostic subgroups within PTCL-NOS (PTCL-GATA3 and PTCL-TBX21). Genomic copy number (CN) analysis and targeted sequencing of these molecular subgroups revealed unique CN abnormalities (CNAs) and oncogenic pathways, indicating distinct oncogenic evolution. PTCL-GATA3 exhibited greater genomic complexity that was characterized by frequent loss or mutation of tumor suppressor genes targeting the CDKN2A /B-TP53 axis and PTEN-PI3K pathways. Co-occurring gains/amplifications of STAT3 and MYC occurred in PTCL-GATA3. Several CNAs, in particular loss of CDKN2A, exhibited prognostic significance in PTCL-NOS as a single entity and in the PTCL-GATA3 subgroup. The PTCL-TBX21 subgroup had fewer CNAs, primarily targeting cytotoxic effector genes, and was enriched in mutations of genes regulating DNA methylation. CNAs affecting metabolic processes regulating RNA/protein degradation and T-cell receptor signaling were common in both subgroups. AITL showed lower genomic complexity compared with other PTCL entities, with frequent co-occurring gains of chromosome 5 (chr5) and chr21 that were significantly associated with IDH2 R172 mutation. CN losses were enriched in genes regulating PI3K-AKT-mTOR signaling in cases without IDH2 mutation. Overall, we demonstrated that novel GEP-defined PTCL subgroups likely evolve by distinct genetic pathways and provided biological rationale for therapies that may be investigated in future clinical trials.

High-risk cytogenetics in multiple myeloma: Further scrutiny of deletions within the IGH gene region enhances risk stratification.

Multiple myeloma is a clonal malignancy of plasma cells in the bone marrow. Risk stratification is partly based on cytogenetic findings that include abnormalities of the IGH locus as determined by fluorescence in situ hybridization (FISH), such as rearrangements that result in either standard-risk or high-risk gene fusions. IGH deletions have been evaluated as a group in multiple myeloma patients with respect to cumulative outcomes but have provided limited guidance. Whether these deletions have the potential to result in gene fusions and thus further stratify patients is unknown. We identified 229 IGH deletions in patients referred for plasma cell dyscrasia genetic testing over 5.5 years. Follow-up was conducted on 208 of the deletions with dual fusion FISH probes for standard-risk (IGH-CCND1) and high-risk IGH gene fusions (IGH-FGFR3, IGH-MAF, IGH-MAFB). Of all deletions identified with follow-up, 44 (21%) resulted in a gene fusion as detected by FISH, 15 (7%) of which were fusion partners associated with high-risk multiple myeloma. All fusion-positive 3'-IGH deletions (6 fusions) resulted in high-risk IGH-FGFR3 fusions. Of the 15 high-risk fusion-positive cases, eight were without other high-risk cytogenetic findings. This study is the first to evaluate the presence of IGH gene fusions upon identification of IGH deletions and to characterize the deletion locus. Importantly, these findings indicate that follow-up FISH studies with dual fusion probes should be standard of care when IGH deletions are identified in multiple myeloma.

ADA3 regulates normal and tumor mammary epithelial cell proliferation through c-MYC.

BACKGROUND: We have established the critical role of ADA3 as a coactivator of estrogen receptor (ER), as well as its role in cell cycle progression. Furthermore, we showed that ADA3 is predominantly nuclear in mammary epithelium, and in ER+, but is cytoplasmic in ER- breast cancers, the latter correlating with poor survival. However, the role of nuclear ADA3 in human mammary epithelial cells (hMECs), and in ER+ breast cancer cells, as well as the importance of ADA3 expression in relation to patient prognosis and survival in ER+ breast cancer have remained uncharacterized. METHODS: We overexpressed ADA3 in hMECs or in ER+ breast cancer cells and assessed the effect on cell proliferation. The expression of ADA3 was analyzed then correlated with the expression of various prognostic markers, as well as survival of breast cancer patients. RESULTS: Overexpression of ADA3 in ER- hMECs as well as in ER+ breast cancer cell lines enhanced cell proliferation. These cells showed increased cyclin B and c-MYC, decreased p27 and increased SKP2 levels. This was accompanied by increased mRNA levels of early response genes c-FOS, EGR1, and c-MYC. Analysis of breast cancer tissue specimens showed a significant correlation of ADA3 nuclear expression with c-MYC expression. Furthermore, nuclear ADA3 and c-MYC expression together showed significant correlation with tumor grade, mitosis, pleomorphism, NPI, ER/PR status, Ki67 and p27 expression. Importantly, within ER+ cases, expression of nuclear ADA3 and c-MYC also significantly correlated with Ki67 and p27 expression. Univariate Kaplan Meier analysis of four groups in the whole, as well as the ER+ patients showed that c-MYC and ADA3 combinatorial phenotypes showed significantly different breast cancer specific survival with c-MYC-high and ADA3-Low subgroup had the worst outcome. Using multivariate analyses within the whole cohort and the ER+ subgroups, the significant association of ADA3 and c-MYC expression with patients' outcome was independent of tumor grade, stage and size, and ER status. CONCLUSION: ADA3 overexpression enhances cell proliferation that is associated with increased expression of c-MYC. Expression patterns with respect to ADA3/c-MYC can divide patients into four significantly different subgroups, with c-MYC High and ADA3 Low status independently predicting poor survival in patients.

Genome-wide copy-number analyses reveal genomic abnormalities involved in transformation of follicular lymphoma.

Follicular lymphoma (FL), the second most common type of non-Hodgkin lymphoma in the western world, is characterized by the t(14;18) translocation, which is present in up to 90% of cases. We studied 277 lymphoma samples (198 FL and 79 transformed FL [tFL]) using a single-nucleotide polymorphism array to identify the secondary chromosomal abnormalities that drive the development of FL and its transformation to diffuse large B-cell lymphoma. Common recurrent chromosomal abnormalities in FL included gains of 2, 5, 7, 6p, 8, 12, 17q, 18, 21, and X and losses on 6q and 17p. We also observed many frequent small abnormalities, including losses of 1p36.33-p36.31, 6q23.3-q24.1, and 10q23.1-q25.1 and gains of 2p16.1-p15, 8q24.13-q24.3, and 12q12-q13.13, and identified candidate genes that may be driving this selection. Recurrent abnormalities more frequent in tFL samples included gains of 3q27.3-q28 and chromosome 11 and losses of 9p21.3 and 15q. Four abnormalities, gain of X or Xp and losses of 6q23.2-24.1 or 6q13-15, predicted overall survival. Abnormalities associated with transformation of the disease likely impair immune surveillance, activate the nuclear factor-κB pathway, and deregulate p53 and B-cell transcription factors.

Assessing the utility of confirmatory studies following identification of large-scale genomic imbalances by microarray.

PURPOSE: The identification of clinically relevant genomic dosage anomalies assists in accurate diagnosis, prognosis, and medical management of affected individuals. Technological advancements within the field, such as the advent of microarray, have markedly increased the resolution of detection; however, clinical laboratories have maintained conventional techniques for confirmation of genomic imbalances identified by microarray to ensure diagnostic accuracy. In recent years the utility of this confirmatory testing of large-scale aberrations has been questioned but has not been scientifically addressed. METHODS: We retrospectively reviewed 519 laboratory cases with genomic imbalances meeting reportable criteria by microarray and subsequently confirmed with a second technology, primarily fluorescence in situ hybridization. RESULTS: All genomic imbalances meeting reportable criteria detected by microarray were confirmed with a second technology. Microarray analysis generated no false-positive results. CONCLUSION: Confirmatory testing of large-scale genomic imbalances (deletion of ≥150 kb, duplication of ≥500 kb) solely for the purpose of microarray verification may be unwarranted. In some cases, however, adjunct testing is necessary to overcome limitations inherent to microarray. A recommended clinical strategy for adjunct testing following identified genomic imbalances using microarray is detailed.

Leukemic diffuse large B-cell lymphoma in a patient with myeloproliferative disorder.

Essential thrombocythemia is well-known to transform to other myeloid disorders, such as leukemia; however, the risk for development of lymphoma is not as well studied. This case report discusses a 76-year-old man with a history of prefibrotic post-essential thrombocythemia myelofibrosis on ruxolitinib, who developed anemia, thrombocytopenia, and leukocytosis with peripheral blasts. Results of a bone marrow biopsy and PET and CT scans revealed stage IV leukemic diffuse large B-cell lymphoma. Several days after cessation of ruxolitinib, the patient developed fevers, hypotension, and low-grade disseminated intravascular coagulation, and subsequently developed spontaneous tumor lysis syndrome, which resulted in death. This case is unique in several aspects: it highlights the rare possibility of lymphomatous transformation of myeloproliferative disorders, an unusual presentation of lymphoma masquerading as leukemia, and the possibility of ruxolitinib withdrawal syndrome. Additionally, this case serves as a reminder that the use of novel therapies should be adopted after a thorough assessment of long-term risks, including those associated with abrupt withdrawal.

HACE1 is a tumor suppressor gene candidate in natural killer cell neoplasms.

HACE1 is an E3 ubiquitin ligase located in 6q21, the genomic region frequently deleted in natural killer (NK) cell malignancies. Here, we report HACE1 as a candidate tumor suppressor gene silenced through a combination of deletion and cytosine phosphate guanine island hypermethylation. We detected deletion of HACE1 in malignant NK cell lines (6 of 9, 67%) and primary biopsies (5 of 15, 33%) by quantitative PCR, with most of the specimen showing cytosine phosphate guanine island hypermethylation in the remaining allele, leading to low mRNA transcription. The ectopic expression of HACE1 in an HACE1-null NK cell line led to apoptosis and G2/M cell cycle arrest. Moreover, HACE1 expression was up-regulated in IL-2-activated normal NK cells and NK cells cocultured with an engineered NK cell target, K562 Clone 9.mbIL21, suggesting its role in the regulation of NK cell homeostasis. In conclusion, HACE1 is another potent tumor suppressor gene located within the 6q21 region, and loss of function of multiple tumor suppressor genes within 6q21 may be a critical determinant of NK cell lymphomagenesis.

Allogeneic stem cell transplantation for Philadelphia chromosome-positive acute myeloid leukemia.

Philadelphia chromosome-positive acute myeloid leukemia (Ph(+)-AML) has a poor response to anthracycline- and cytarabine-containing regimens, high relapse rate, and dismal prognosis. Although therapy with imatinib and allogeneic stem cell transplantation (allo-SCT) is promising, relatively short follow-up limits understanding of long-term results of these therapies. This report describes the outcomes of 3 cases of Ph(+)-AML diagnosed and transplanted at the University of Nebraska Medical Center between 2004 and 2011. These patients, young and without major comorbidities, received induction therapy with 7 days of cytarabine and 3 days of idarubicin along with imatinib and consolidation therapy with high-dose cytarabine (with or without imatinib). All patients underwent 10/10 HLA-matched peripheral blood allo-SCT (sibling donor for first and third patients and unrelated donor for the second patient; all had acute graft-versus-host disease (GVHD), and the first and third patients had chronic GVHD. All patients are currently alive and experiencing complete remission at 116, 113, and 28 months after diagnosis, respectively. This report shows that the use of allo-SCT with resultant graft-versus-leukemia effect and the addition of imatinib can result in long-term remission and possible cure in some patients with Ph(+)-AML.

B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and burkitt lymphoma: study of 39 cases.

B-cell lymphoma, unclassifiable (B-UCL), with features intermediate between diffuse large B-cell lymphoma and Burkitt lymphoma, is a poorly characterized entity. Therefore, we investigated cases of B-UCL treated by the Nebraska Lymphoma Study Group (NLSG). We searched the NLSG registry for years 1985-2010 for cases of B-UCL. Immunohistochemical stains and fluorescence in situ hybridization studies for MYC, BCL2 and BCL6 gene rearrangements were performed. Among the 39 cases studied, 54% were male and 46% were female, with a median age of 69 years. The majority of patients presented with advanced-stage disease (62%) and had high (3-5) International Prognostic Index (IPI) scores (54%). The median overall survival (OS) was only 9 months and the 5-year OS was 30%. Patients with low IPI scores (0-2) had a better survival than those with high scores (3-5). The cases were genetically heterogeneous and included 11 'double-hit' lymphomas with rearrangements of both MYC and BCL2 or BCL6. None of the immunohistochemical or genetic features was predictive of survival. This B-cell lymphoma is a morphologically-recognizable entity with a spectrum of genetic abnormalities. New and better treatments are needed for this aggressive lymphoma.

Small molecule antagonist of CXCR2 and CXCR1 inhibits tumor growth, angiogenesis, and metastasis in pancreatic cancer.

Pancreatic cancer (PC) has a poor prognosis, and current therapeutic strategies are ineffective in advanced diseases. We and others have shown the aberrant expression of CXCR2 and its ligands in PC development and progression. Our objective for this study was to evaluate the therapeutic utility of CXCR2/1 targeting using an small molecule antagonist, SCH-479833, in different PC preclinical murine models (syngeneic or xenogeneic). Our results demonstrate that CXCR2/1 antagonist had both antitumor and anti-metastatic effects in PC. CXCR2/1 antagonist treatment inhibited tumor cell proliferation, migration, angiogenesis, and recruitment of neutrophils, while it increased apoptosis. Treatment with the antagonist enhanced fibrosis, tumor necrosis, and extramedullary hematopoiesis. Together, these findings suggest that selectively targeting CXCR2/1 with small molecule inhibitors is a promising therapeutic approach for inhibiting PC growth, angiogenesis, and metastasis.

Optical Genome Mapping Helps to Identify BCR::JAK2 Rearrangement Arising from Cryptic Complex Chromosomal Aberrations: A Case Report and Literature Review.

We report a case of myeloproliferative neoplasm, not otherwise specified (MPN-NOS)-transformed AML with BCR::JAK2 rearrangement. Chromosomal analysis indicated a simple abnormal karyotype 46,XY,t(7;17)(q21;q24),t(9;22)(p24;q11.2). Fluorescence in situ hybridization (FISH) using a BCR/ABL1/ASS1 probe set suggested a possible BCR rearrangement and a reflex JAK2 breakapart probe indicated JAK2 rearrangement, most likely partnered with BCR. Optical genome mapping (OGM) analysis confirmed BCR::JAK2 derived through an inv(9)(p24p13) after a t(9;22)(p13;q11.2) in this case. Due to the complexity of chromosomal aberrations, disruption and/or rearrangement of other genes such as KIF24::BCR, JAK2::KIF24/UBAP1, and CDK6:SOX9 were also identified by OGM. Although the functionality and clinical importance of these novel rearrangements were unknown, disruption of these genes might be associated with a poorer response to chemotherapy and disease progression. We also reviewed all cases with BCR::JAK2 rearrangement reported in the literature. In conclusion, a suspected t(9;22)/BCR::JAK2 rearrangement warrants further characterization with genomic assays such as OGM, whole chromosome sequencing, and RNA sequencing to explore other gene disruptions and/or rearrangements.

The proliferation gene expression signature is a quantitative integrator of oncogenic events that predicts survival in mantle cell lymphoma.

We used gene expression profiling to establish a molecular diagnosis of mantle cell lymphoma (MCL), to elucidate its pathogenesis, and to predict the length of survival of these patients. An MCL gene expression signature defined a large subset of MCLs that expressed cyclin D1 and a novel subset that lacked cyclin D1 expression. A precise measurement of tumor cell proliferation, provided by the expression of proliferation signature genes, identified patient subsets that differed by more than 5 years in median survival. Differences in cyclin D1 mRNA abundance synergized with INK4a/ARF locus deletions to dictate tumor proliferation rate and survival. We propose a quantitative model of the aberrant cell cycle regulation in MCL that provides a rationale for the design of cell cycle inhibitor therapy in this malignancy.

Composite Classic Hodgkin Lymphoma and Follicular Lymphoma: A Clinicopathologic Study of 22 Cases With Review of 27 Additional Cases in the Literature.

Composite classic Hodgkin lymphoma and follicular lymphoma (CHLFL) is a rare and poorly characterized entity. Herein, we report the clinicopathologic features of 22 cases of CHLFL from 3 institutions and we assess 27 additional cases reported in the literature. In our cohort (n=22), patients with CHLFL had a median age of 61 years and an equal male to female incidence. Most cases (95%) arose de novo with the remaining patients having a history of non-Hodgkin lymphoma. CHLFL always involved lymph nodes (100%) and most cases (95%) revealed 2 distinct areas separately diagnostic for CHL and FL. The CHL component represented a variable proportion of the overall neoplasm (5% to 90%) and was either mixed cellularity (82%) or nodular sclerosis (18%) type. The Hodgkin/Reed-Sternberg cells expressed CD30 (100%), PAX5 (100%), CD15 (62%), BCL6 (47%), BCL2 (29%), and EBER (25%), in a polymorphous inflammatory background typical of CHL. The FL component was low-grade in 55%, grade 3A in 36%, and grade 3B in 9% of cases. All 3 cases investigated by cytogenetic methods for a clonal relationship between the CHL and FL components were clonally related. These clinicopathologic features of our cohort are similar to those of cases reported in the literature. The 5-year overall survival in combined patients with CHLFL (n=49) was 48%, comparable to CHL but worse than FL in the elderly. In summary, CHLFL is a rare entity that most often occurs in older adults, involves lymph nodes, and most commonly presents de novo. In the small number of cases assessed, the CHL and FL components are usually clonally related suggesting that the CHL and FL components may share a common progenitor B-cell, likely a mutated germinal center B-cell.

The Missing LNK: Evolution from Cytosis to Chronic Myelomonocytic Leukemia in a Patient with Multiple Sclerosis and Germline SH2B3 Mutation.

Chronic myelomonocytic leukemia (CMML) is a rare but distinct hematological neoplasm with overlapping features of myelodysplastic syndrome (MDS) and myeloproliferative neoplasm (MPN). Individuals with CMML have persistent monocytosis and bone marrow dyspoiesis associated with various constitutional symptoms like fevers, unintentional weight loss, or night sweats. It is established that there is a strong association of CMML with preceding or coexisting autoimmune diseases and systemic inflammatory syndromes affecting around 20% of patients. Various molecular abnormalities like TET2, SRSF2, ASXL1, and RAS are reported in the pathogenesis of CMML, but no such mutations have been described to explain the strong association of autoimmune diseases and severe inflammatory phenotype seen in CMML. Germline mutation in SH2B adaptor protein 3 (SH2B3) had been reported before to affect a family with autoimmune disorders and acute lymphoblastic leukemia. In this report, we describe the first case of a female subject with many years of preceding history of multiple sclerosis before the diagnosis of CMML. We outline the evidence supporting the pathogenic role of SH2B3 p.E395K germline mutation, connecting the dots of association between autoimmune diseases and CMML genesis.

Risk factors for non-Hodgkin lymphoma subtypes defined by histology and t(14;18) in a population-based case-control study.

The t(14;18) chromosomal translocation is the most common cytogenetic abnormality in non-Hodgkin lymphoma (NHL), occurring in 70-90% of follicular lymphomas (FL) and 30-50% of diffuse large B-cell lymphomas (DLBCL). Previous t(14;18)-NHL studies have not evaluated risk factors for NHL defined by both t(14;18) status and histology. In this population-based case-control study, t(14;18) status was determined in DLBCL cases using fluorescence in situ hybridization on paraffin-embedded tumor sections. Polytomous logistic regression was used to evaluate the association between a wide variety of exposures and t(14;18)-positive (N=109) and -negative DLBCL (N=125) and FL (N=318), adjusting for sex, age, race, and study center. Taller height, more lifetime surgeries, and PCB180 exposure were associated with t(14;18)-positivity. Taller individuals (third tertile vs. first tertile) had elevated risks of t(14;18)-positive DLBCL (odds ratio [OR] = 1.8, 95% confidence interval [CI] 1.1-3.0) and FL (OR=1.4, 95%CI 1.0-1.9) but not t(14;18)-negative DLBCL. Similar patterns were seen for individuals with more lifetime surgeries (13+ vs. 0-12 surgeries; t(14;18)-positive DLBCL OR=1.4, 95%CI 0.7-2.7; FL OR=1.6, 95%CI 1.1-2.5) and individuals exposed to PCB180 greater than 20.8 ng/g (t(14;18)-positive DLBCL OR=1.3, 95%CI 0.6-2.9; FL OR=1.7, 95%CI 1.0-2.8). In contrast, termite treatment and high alpha-chlordane levels were associated with t(14;18)-negative DLBCL only, suggesting that these exposures do not act through t(14;18). Our findings suggest that putative associations between NHL and height, surgeries, and PCB180 may be t(14;18)-mediated and provide support for case-subtyping based on molecular and histologic subtypes. Future efforts should focus on pooling data to confirm and extend previous research on risk factors for t(14;18)-NHL subtypes.

Frequency, variations, and prognostic implications of chromosome 14q32 deletions in chronic lymphocytic leukemia.

The clinical implications of deletions within chromosome 14q32 in CLL pathogenesis remain unclear. We examined the frequency of 14q32 deletions among CLL cases by karyotype and FISH, categorized the variation using genomic microarray, and assessed the prognostic impact by time-to-first-treatment (TTFT) analysis. A 14q32 abnormality was detected in 35 % (245/698) of cases, with the majority containing a 5' partial telomeric 14q32 deletion. These deletions within the IGH variable region (35/40) ranged from 236 kb to 1.4 Mb involving FAM30A, ADAM6, LINC00226, and LINC00221. The 214 kb minimum deleted region implicated in CLL pathogenesis encompassed LINC00221. Cases with a 14q32 deletion had a shorter median TTFT compared to cases with a sole deletion/nullisomy 13q, a good prognostic indicator, and longer than cases with a sole deletion of 11q or 17p, conferring an unfavorable prognosis. This investigation underscores the importance of comprehensive testing to apprehend the implications of 14q32 deletions in CLL.

An increased frequency of 13q deletions detected by fluorescence in situ hybridization and its impact on survival in children and adolescents with Burkitt lymphoma: results from the Children's Oncology Group study CCG-5961.

Burkitt lymphoma (BL), an aggressive B-cell malignancy, is often curable with short intensive treatment regiments. Nearly all BLs contain rearrangements of the MYC/8q24 region; however, recent cytogenetic studies suggest that certain secondary chromosomal aberrations in BL correlate with an adverse prognosis. In this multi-centre study, the frequency and impact on clinical outcome of del(13q) and +7 in addition to MYC rearrangements as detected by fluorescence in situ hybridization (FISH) in children and adolescents with intermediate and high-risk BL registered on Children's Cancer Group study CCG-5961 were investigated. Analysis with 13q14.3 and 13q34 loci specific probes demonstrated deletions of 13q in 38/90 (42%) cases. The loss of either 13q14.3 or 13q34 alone occurred in 14% and 8% respectively, while 20% exhibited loss of both regions. Gain of chromosome 7 was observed in 7/68 (10%) cases and MYC rearrangements were detected in 84/90 (93%). Prognostic analysis controlling for known risk factors demonstrated that patients exhibiting loss of 13q, particularly 13q14.3, had a significant decrease in 5-year overall survival (77% vs. 95%, P = 0.012). These observations indicate that del(13q) occurs in childhood BL at frequencies higher than previously detected by classical cytogenetics and underscores the importance of molecular cytogenetics in risk stratification.

Non cell-autonomous reprogramming of adult ocular progenitors: generation of pluripotent stem cells without exogenous transcription factors.

Direct reprogramming of differentiated cells to induced pluripotent stem (iPS) cells by ectopic expression of defined transcription factors (TFs) represents a significant breakthrough towards the use of stem cells in regenerative medicine (Takahashi and Yamanaka Cell 2006;126:663-676). However, the virus-mediated expression of exogenous transcription factors could be potentially harmful and, therefore, represents a barrier to the clinical use of iPS cells. Several approaches, ranging from plasmid-mediated TF expression to introduction of recombinant TFs (Yamanaka Cell 2009;137:13-17; Zhou, Wu, Joo et al. Cell Stem Cell 2009;4:381-384), have been reported to address the risk associated with viral integration. We describe an alternative strategy of reprogramming somatic progenitors entirely through the recruitment of endogenous genes without the introduction of genetic materials or exogenous factors. To this end, we reprogrammed accessible and renewable progenitors from the limbal epithelium of adult rat eye by microenvironment-based induction of endogenous iPS cell genes. Non cell-autonomous reprogramming generates cells that are pluripotent and capable of differentiating into functional neurons, cardiomyocytes, and hepatocytes, which may facilitate autologous cell therapy to treat degenerative diseases.