Isolation, characterization, and transplantation of bone marrow-derived hepatocyte stem cells

Recently it was shown that a population of cells in the bone marrow-expressing hematopoietic stem cell antigens could differentiate into hepatocytes. However, explicitly committed hepatocyte progenitors, which exhibit highly differentiated liver functions, immediately upon isolation, have not yet been isolated from bone marrow. After studying common antigens on blast-like cells in fetal and adult regenerating cholestatic rat livers and human regenerating and malignant livers, we hypothesized that beta-2-microglobulin-negative (beta(2)m(-)) cells might represent dedifferentiated hepatocytes and/or their progenitors. Utilizing a two-step magnetic bead cell-sorting procedure, we show that in bone marrow from rat and human, beta(2)m(-)/Thy-1(+) cells consistently express liver-specific genes and functions. After intraportal infusion into rat livers, bone marrow-derived hepatocyte stem cells (BDHSC) integrated with hepatic cell plates and differentiated into mature hepatocytes. In a culture system simulating liver regeneration and containing cholestatic serum, these cells differentiated into mature hepatocytes and metabolized ammonia into urea. This differentiation was dependent on a yet nondescript humoral signal existing in the cholestatic serum. Transmission electron microscopy and three-dimensional digital reconstruction confirmed hepatocyte ultrastructure of cultured BDHSC.

Rates and patterns of recurrence for percutaneous radiofrequency ablation and open wedge resection for solitary colorectal liver metastasis

INTRODUCTION

The purpose of this study was to compare rates and patterns of disease progression following percutaneous, image-guided radiofrequency ablation (RFA) and nonanatomic wedge resection for solitary colorectal liver metastases.

METHODS

We identified 30 patients who underwent nonanatomic wedge resection for solitary liver metastases and 22 patients who underwent percutaneous RFA because of prior major hepatectomy (50%), major medical comorbidities (41%), or relative unresectability (9%). Serial imaging studies were retrospectively reviewed for evidence of local tumor progression.

RESULTS

Patients in the RFA group were more likely to have undergone prior liver resection, to have a disease-free interval greater than 1 year, and to have had an abnormal carcinoembryonic antigen (CEA) level before treatment. Two-year local tumor progression-free survival (PFS) was 88% in the Wedge group and 41% in the RFA group. Two patients in the RFA group underwent re-ablation, and two patients underwent resection to improve the 2-year local tumor disease-free survival to 55%. Approximately 30% of patients in each group presented with distant metastasis as a component of their first recurrence. Median overall survival from the time of resection was 80 months in the Wedge group vs 31 months in the RFA group. However, overall survival from the time of treatment of the colorectal primary was not significantly different between the two groups.

CONCLUSIONS

Local tumor progression is common after percutaneous RFA. Surgical resection remains the gold standard treatment for patients who are candidates for resection. For patients who are poor candidates for resection, RFA may help to manage local disease, but close follow-up and retreatment are necessary to achieve optimal results.

Current approaches, challenges and future directions for monitoring treatment response in prostate cancer

Prostate cancer is the most commonly diagnosed non-cutaneous neoplasm in men in the United States and the second leading cause of cancer mortality. One in 7 men will be diagnosed with prostate cancer during their lifetime. As a result, monitoring treatment response is of vital importance. The cornerstone of current approaches in monitoring treatment response remains the prostate-specific antigen (PSA). However, with the limitations of PSA come challenges in our ability to monitor treatment success. Defining PSA response is different depending on the individual treatment rendered potentially making it difficult for those not trained in urologic oncology to understand. Furthermore, standard treatment response criteria do not apply to prostate cancer further complicating the issue of treatment response. Historically, prostate cancer has been difficult to image and no single modality has been consistently relied upon to measure treatment response. However, with newer imaging modalities and advances in our understanding and utilization of specific biomarkers, the future for monitoring treatment response in prostate cancer looks bright.

Molecular targeting of CSN5 in human hepatocellular carcinoma: a mechanism of therapeutic response

Development of targeted therapy for hepatocellular carcinoma (HCC) remains a major challenge. We have recently identified an elevated expression of the fifth subunit of COP9 signalosome (CSN5) in early HCC as compared to dysplastic stage. In the present study, we explored the possibility of CSN5 being a potential therapeutic target for HCC. Our results show that CSN5 knockdown by small interfering (si) RNA caused a strong induction of apoptosis and inhibition of cell cycle progression in HCC cells in vitro. The downregulation of CSN5 was sufficient to interfere with CSN function as evidenced by the accumulation of neddylated Cullin1 and changes in the protein levels of CSN controlled substrates SKP2, p53, p27 and NF-kB, albeit to a different degree depending on the HCC cell line, which could account for the CSN5 knockdown phenotype. The transcriptomic analysis of CSN5 knockdown signature showed that the anti-proliferative effect was driven by a common subset of molecular alterations including downregulation of CDK6 and ITGB1, which were functionally interconnected with key oncogenic regulators MYC and TGFβ1 involved in the control of proliferation, apoptotic cell death and HCC progression. Consistent with microarray analysis, western blotting revealed that CSN5 depletion increased phosphorylation of Smad 2/3, key mediators of TGFβ1 signaling, decreased the protein levels of ITGB1, CDK6, and cyclin D1 and caused reduced expression of anti-apoptotic Bcl-2 while elevating the levels of pro-apoptotic Bak. A chemically modified variant of CSN5 siRNA was then selected for in vivo application based on the growth inhibitory effect and minimal induction of unwanted immune response. Systemic delivery of the CSN5 3/8 variant by stable-nucleic-acid-lipid-particles (SNALP) significantly suppressed the tumor growth in Huh7-luc⁺ orthotopic xenograft model. Taken together, these results indicate that CSN5 plays a pivotal role in HCC pathogenesis and maybe an attractive molecular target for systemic HCC therapy.

Liver repopulation with bone marrow derived cells improves the metabolic disorder in the Gunn rat

BACKGROUND

Reversible ischaemia/reperfusion (I/R) liver injury has been used to induce engraftment and hepatic parenchymal differentiation of exogenous beta2-microglubulin(-)/Thy1(+) bone marrow derived cells.

AIM

To test the ability of this method of hepatic parenchymal repopulation, theoretically applicable to clinical practice, to correct the metabolic disorder in a rat model of congenital hyperbilirubinaemia.

METHODS AND RESULTS

Analysis by confocal laser microscopy of fluorescence labelled cells and by immunohistochemistry for beta2-microglubulin, 72 hours after intraportal delivery, showed engraftment of infused cells in liver parenchyma of rats with I/R, but not in control animals with non-injured liver. Transplantation of bone marrow derived cells obtained from GFP-transgenic rats into Lewis rats resulted in the presence of up to 20% of GFP positive hepatocytes in I/R liver lobes after one month. The repopulation rate was proportional to the number of transplanted cells. Infusion of GFP negative bone marrow derived cells into GFP positive transgenic rats resulted in the appearance of GFP negative hepatocytes, suggesting that the main mechanism underlying parenchymal repopulation was differentiation rather than cell fusion. Transplantation of wild type bone marrow derived cells into hyperbilirubinaemic Gunn rats with deficient bilirubin conjugation after I/R damage resulted in 30% decrease in serum bilirubin, the appearance of bilirubin conjugates in bile, and the expression of normal UDP-glucuronyltransferase enzyme evaluated by polymerase chain reaction.

CONCLUSIONS

I/R injury induced hepatic parenchymal engraftment and differentiation into hepatocyte-like cells of bone marrow derived cells. Transplantation of bone marrow derived cells from non-affected animals resulted in the partial correction of hyperbilirubinaemia in the Gunn rat.

Primary anorectal melanoma: an update

The anorectum is a rare anatomic location for primary melanoma. Mucosal melanoma is a distinct biological and clinical entity from the more common cutaneous melanoma. It portrays worse prognosis than cutaneous melanoma, with distant metastases being the overwhelming cause of morbidity and mortality. Surgery is the treatment of choice, but significant controversy exists over the extent of surgical resection. We present an update on the state of the art of anorectal mucosal melanoma. To illustrate the multimodality approach to anorectal melanoma, we present a typical patient.

Local and remote ischemia-reperfusion injury is mitigated in mice overexpressing human C1 inhibitor

Activation of the classical complement pathway is crucially involved in complement-mediated endothelial cell damage in ischemia-reperfusion injury. C1 inhibitor is the only known physiological inhibitor of classical complement pathway activation. Transgenic mice overexpressing human C1 inhibitor were used in a surgical lower torso and a liver ischemia-reperfusion model. Organ-specific endothelial disruption was determined by 125I-tagged albumin extravasation. In the lower torso ischemia-reperfusion model, transgenic mice overexpressing the C1 inhibitor were protected in the muscle and the lungs from endothelial cell damage. In the liver ischemia-reperfusion model, endothelial cell integrity was preserved in transgenic animals in the liver, the gut and the lungs. Our data indicate that inhibiting complement activation by a transgenic approach is effective in protection against ischemia-reperfusion injury.

Infiltrating lobular carcinoma of the breast presenting as gastrointestinal obstruction: a mini review

One in twelve American women will develop breast cancer, with infiltrating lobular carcinoma (ILC) comprising approximately 15% of these cases. The incidence of ILC has been increasing over the last several decades. It has been hypothesized that this increase is associated with combined replacement hormonal therapy. Although pathologically distinct from infiltrating ductal carcinoma (IDC), ILC is treated in the same manner as IDC. However, ILC demonstrates significantly different patterns of late local recurrence and distant metastasis. The incidence of extra-hepatic gastrointestinal metastases is reported to be 6% to 18%, with stomach being most common. Herein, we present a brief review of the literature and a typical case involving ILC initially presenting as a small bowel obstruction. Evidence suggests that the late clinical patterns of ILC are distinctly separate from IDC and physicians need be cognizant of its late local recurrence and unique late metastatic pattern. Different follow up strategy should be entertained in patients with ILC.

Multi-Parametric MRI-Directed Focal Salvage Permanent Interstitial Brachytherapy for Locally Recurrent Adenocarcinoma of the Prostate: A Novel Approach

Even with the technological advances of dose-escalated IMRT with the addition of the latest image guidance technologies, local failures still occur. The combination of MRI-based imaging techniques can yield quantitative information that reflects on the biological properties of prostatic tissues. These techniques provide unique information that can be used for tumor detection in the treated gland. With the advent of these improved imaging modalities, it has become possible to more effectively image local recurrences within the prostate gland. With better imaging, these focal recurrences can be differentially targeted with salvage brachytherapy minimizing rectal and bladder toxicity. Here we report a novel use of MRI-directed focal brachytherapy after local recurrence. This technique offers a unique opportunity to safely and successfully treat recurrent prostate cancer, previously treated with definitive radiation therapy. The use of multi-parametric MRI-directed focal salvage permanent interstitial brachytherapy for locally recurrent adenocarcinoma of the prostate is a promising strategy to avoid more aggressive and expensive treatments that are associated with increased morbidity, potentially improving survival at potentially lower costs.

Kidney Transplantation Improves Survival and Is Indicated in Fabry’s Disease

BACKGROUND

Fabry's disease (FD) is an inborn error of glycosphingolipid catabolism with progressive systemic deposition of globotriaosylceramide thereby leading to renal and cardiac failure. Current therapy involves symptomatic medical management, dialysis, enzyme replacement therapy, kidney transplantation (KTx), and more recently gene therapy. Case fatalities occur in the fourth decade of life resulting from uremia unless dialysis or KTx is undertaken.

STUDY DESIGN

This is a retrospective study aimed at determining the effect of KTx on the long-term outcome of patients with FD.

RESULTS

Between 1964 and 1998, ten patients with FD received KTx at our institutions. Actuarial patient and graft survivals were 100% and 90% at 5 years; 76% and 66% at 10 years. One kidney graft was lost due to rejection. Patient survival data compared favorably at 5 years with survival of FD patients on hemodialysis alone (41%, P < .05). Five patients are alive at the time of this study, and five patients died with median survival time after KTx of 128 months (range: 74-160 months).

CONCLUSIONS

This study demonstrates an excellent outcome in patients with FD in the first decade after KTx. In the absence of a severe contraindication, we advocate KTx to improve the overall prognosis of patients with renal failure due to FD. Based on the data, enzyme replacement therapy after KTx seems indicated, as FD progresses posttransplant, leading to case fatalities in the second decade after KTx.

Laparoscopic adrenalectomy for large adrenal masses: a challenge or a routine?

AIM

The increased incidence of malignancy and the concern for higher rate of complications with laparoscopic resection of larger tumors typically limits laparoscopic adrenalectomy to small adrenal masses. We used our prospectively collected database to compare laparoscopic adrenalectomy outcomes between small and large adrenal tumors.

METHODS

Operative details and outcomes were compared by adrenal mass size size: Group A≤4 cm and Group B>4 cm, for consecutive laparoscopic adrenalectomies performed between 2009 and 2013.

RESULTS

Group A (N.=50) and Group B (N.=27) subjects had similar operative times (131 vs. 132 min, P=0.48). Group B subjects were older, had more adrenal malignancies, and had a higher blood loss with a slightly larger change in hemoglobin than Group A subjects; however, no subject required blood transfusion and complication rates were similar between groups (4% vs. 11%, P=0.34). One subject from each group required conversion to open adrenalectomy.

CONCLUSION

Laparoscopic adrenalectomy can be performed safely for adrenal masses >4 cm and size is not a contraindication to the laparoscopic approach.