Liver Transplantation for Hepatocellular Carcinoma: A Narrative Review and A Glimpse into The Future.

Liver transplantation (LT) is a highly effective treatment for carefully selected patients with hepatocellular carcinoma (HCC). In this review, we explored the development of LT selection criteria and organ allocation policies, comparing original data to underscore their historical progression into the intricate task of quantitatively estimating pre- and post-LT survivals. We emphasized the role of biomarkers such as serum alpha-fetoprotein, Des-gamma-carboxy-prothrombin, circulating tumor cells, and circulating tumor DNA in predicting patient outcomes. Additionally, we examined the transplant-associated survival benefits and the difficulties in accurately calculating these benefits. We also reviewed recent advancements in targeted therapy and checkpoint inhibitors for advanced, inoperable HCC and projected their integration into LT for HCC. We further discussed the growing use of living donor liver transplants in the United States and compared its outcomes with those of deceased donor liver transplants. Furthermore, we examined the progress in machine perfusion techniques, which have shown potential in improving patient outcomes and enlarging the donor pool. These advancements present opportunities to enhance LT patient survivals, refine selection criteria, establish new priority metrics, develop innovative bridging and downstaging strategies, and formulate redesigned LT strategies for HCC treatments.

Prescription patterns of pancreatic enzyme replacement therapy for patients with pancreatic cancer in the United States.

BACKGROUND: Exocrine pancreatic insufficiency (EPI) is frequently seen in patients with pancreatic cancer (PDAC) and is thought to contribute to nutritional complications. While EPI can be pharmacologically temporized with pancreatic enzyme replacement therapy (PERT), there is lack of clear evidence informing its use in PDAC. Here we aim to survey pancreatic surgeons regarding their utilization of PERT in the management of EPI for PDAC. METHODS: An online survey was distributed to the members of The Americas Hepato-Pancreato-Biliary Association (AHPBA) and The Pancreas Club. RESULTS: 86.5% (180/208) of surgeons prescribe PERT for at least some resectable/borderline resectable PDAC cases. Only a minority of surgeons order investigations to confirm EPI before starting PERT (28.1%) or test for adequacy of therapy (28.3%). Few surgeons believe that PERT has an effect on overall survival (19.7%) or disease-free survival (6.25%) in PDAC. CONCLUSION: PERT is widely prescribed in patients with resectable/borderline resectable PDAC, but investigations establishing EPI and assessing PERT adequacy are underutilized. A substantial proportion of surgeons are unclear as to the effect of PERT on survival outcomes in PDAC. These data call for prospective studies to establish guidelines for optimal use of PERT and its effects on survival outcomes in PDAC.

Minnelide synergizes with conventional chemotherapy by targeting both cancer and associated stroma components in pancreatic cancer.

Addition of nab-paclitaxel to gemcitabine offers a survival benefit of only 6 weeks over gemcitabine alone at a cost of increased toxicity in PDAC. The goal of the present study is to evaluate the efficacy of Minnelide, a water-soluble prodrug of triptolide, in combination with the standard of care regimen for chemotherapy with the added advantage of reducing the doses of these drugs to minimize toxicity. Pancreatic cancer cell lines were implanted subcutaneously or orthotopically in athymic nude or C57BL/6J mice. Subsequently, animals were randomized and received saline or minnelide or full dose chemotherapy or low dose chemotherapy or minnelide in combination with low dose chemotherapy. Our results show that a combination of low doses of Minnelide with Gemcitabine + nab-paclitaxel significantly inhibited tumor progression and increased the survival of tumor-bearing mice in comparison with conventional chemotherapy alone. Moreover, combination therapy significantly reduced cancer-related morbidity by decreasing ascites and metastasis and effectively targeted both cancer and the associated stroma. In vitro studies with a combination of low doses of triptolide and paclitaxel significantly decreased the cell viability, increased apoptosis and led to significantly increased M-phase cell cycle arrest in various pancreatic cancer cell lines as compared to either drug alone. Our results show that Minnelide synergizes with conventional chemotherapy leading to a significant reduction in the doses of these toxic drugs, all the while achieving better efficacy in the treatment of PDAC. This combination effectively targeted both the cancer and the associated stromal components of pancreatic cancer.

Pirfenidone increases IL-10 and improves acute pancreatitis in multiple clinically relevant murine models.

Despite decades of research, there is no specific therapy for acute pancreatitis (AP). In the current study, we have evaluated the efficacy of pirfenidone, an antiinflammatory and antifibrotic agent that is approved by the FDA for treatment of idiopathic pulmonary fibrosis (IPF), in ameliorating local and systemic injury in AP. Our results suggest that treatment with pirfenidone in therapeutic settings (e.g., after initiation of injury), even when administered at the peak of injury, reduces severity of local and systemic injury and inflammation in multiple models of AP. In vitro evaluation suggests that pirfenidone decreases cytokine release from acini and macrophages and disrupts acinar-macrophage crosstalk. Therapeutic pirfenidone treatment increases IL-10 secretion from macrophages preceding changes in histology and modulates the immune phenotype of inflammatory cells with decreased levels of inflammatory cytokines. Antibody-mediated IL-10 depletion, use of IL-10-KO mice, and macrophage depletion experiments confirmed the role of IL-10 and macrophages in its mechanism of action, as pirfenidone was unable to reduce severity of AP in these scenarios. Since pirfenidone is FDA approved for IPF, a trial evaluating the efficacy of pirfenidone in patients with moderate to severe AP can be initiated expeditiously.

Hsp70 modulates immune response in pancreatic cancer through dendritic cells.

Heat shock protein 70 (Hsp70), a protein chaperone, is known to promote cell survival and tumor progression. However, its role in the tumor microenvironment (TME) is largely unknown. We specifically evaluated Hsp70 in the TME by implanting tumors in wild-type (WT) controls or Hsp70-/- animals, thus creating a TME with or without Hsp70. Loss of Hsp70 led to significantly smaller tumors; there were no differences in stromal markers, but interestingly, depletion of CD8 + T-cells abrogated this tumor suppressive effect, indicating that loss of Hsp70 in the TME affects tumor growth through the immune cells. Compared to WT, adoptive transfer of Hsp70-/- splenocytes exhibited greater antitumor activity in immunodeficient NSG and Rag 1-/- mice. Hsp70-/- dendritic cells showed increased expression of MHCII and TNF-α both in vitro and in vivo. These results suggest that the absence of Hsp70 in the TME inhibits tumors through increased dendritic cell activation. Hsp70 inhibition in DCs may emerge as a novel therapeutic strategy against pancreatic cancer.

An Immunocompetent Model of Pancreatic Cancer Resection and Recurrence.

BACKGROUND: Even after surgical resection, most patients with localized pancreatic ductal adenocarcinoma (PDAC) succumb to disease recurrence. Current animal models do not recapitulate this pattern of disease recurrence. Our goal was to develop a clinically relevant, immunocompetent model of PDAC resection to study recurrence and evaluate therapy. METHODS: Pancreatic cancer cells derived from tumors arising in KPC (LSL-KrasG12D/+; LSL-Trp53R172H/+; Pdx-1-Cre) mice were co-injected with stromal cells (pancreatic stellate cells) into the pancreas of immunocompetent mice to simulate the stroma-rich tumors seen in human PDAC. After allowing tumors to form, we resected these localized tumors and followed the mice for tumor recurrence. Circulating tumor cells (CTCs) were isolated, and systemic chemotherapy or immunotherapy was administered following tumor resection. RESULTS: Tumors formed by co-injection of KPC cells and stromal cells demonstrated a dense desmoplastic reaction similar to that seen in human disease. Resection at days 15 and 21 after implantation revealed uniform tumor volumes of 92 ± 19 mm3 on day 15 and 444 ± 54 mm3 on day 21. Histology of resected tumors showed negative margins. Resembling human PDAC, mice that underwent resection showed improved median survival (58 vs 47 days) but most animals developed intra-abdominal recurrence on follow-up. Adjuvant chemotherapy (median survival 69 vs 58 days), but not immunotherapy (median survival 69 vs 65 days) tended towards improved survival as seen in human disease. Circulating tumor cells were reliably identified from mice with and without resection, suggesting utility of this model in studying tumor metastases and recurrence. CONCLUSION: We describe an immunocompetent animal model that recapitulates human disease in morphology and recurrence patterns. We show that it can be used to evaluate therapy in clinical scenarios associated with surgical resection and may help characterize factors responsible for disease recurrence.

Correction to: Pre-clinical evaluation of Minnelide as a therapy for acute myeloid leukemia.

Following publication of the original article [1], the authors found an error in Figure 3. The middle panel of Figure 3a was inadvertently duplicated.

Pre-clinical evaluation of Minnelide as a therapy for acute myeloid leukemia.

BACKGROUND: There is an urgent need for novel and effective treatment options for acute myeloid leukemia (AML). Triptolide, a diterpenoid tri-epoxide compound isolated from the herb Tripterygium wilfordii and its water-soluble pro-drug-Minnelide have shown promising anti-cancer activity. A recent clinical trial for patients with solid tumors confirmed the safety and efficacy at biologically equivalent doses of 0.2 mg/kg/day and lower. METHODS: Cell viability of multiple AML cell lines as well as patient apheresis samples were evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) based assay. Apoptosis was evaluated by estimating the amount of cleaved caspase. AML cell line (THP1-Luc) was implanted in immunocompromised mice and treated with indicated doses of Minnelide. Leukemic burden before and after treatment was evaluated by imaging in an In Vivo Imaging System (IVIS). RESULTS: In the current study, we show that Minnelide, at doses below maximum tolerated dose (MTD) demonstrates leukemic clearance of both primary AML blasts and luciferase expressing THP-1 cells in mice. In vitro, multiple primary AML apheresis samples and AML cell lines (THP-1, KG1, Kasumi-1, HL-60) were sensitive to triptolide mediated cell death and apoptosis in low doses. Treatment with triptolide led to a significant decrease in the colony forming ability of AML cell lines as well as in the expression of stem cell markers. Additionally, it resulted in the cell cycle arrest in the G1/S phase with significant downregulation of c-Myc, a major transcriptional regulator mediating cancer cell growth and stemness. CONCLUSION: Our results suggest that Minnelide, with confirmed safety and activity in the clinic, exerts a potent anti-leukemic effect in multiple models of AML at doses easily achievable in patients.

The Role of the Microbiome in Immunologic Development and its Implication For Pancreatic Cancer Immunotherapy.

Our understanding of the microbiome and its role in immunity, cancer initiation, and cancer progression has evolved significantly over the past century. The "germ theory of cancer" was first proposed in the early 20th century, and shortly thereafter the bacterium Helicobacter pylori, and later Fusobacterium nucleatum, were implicated in the development of gastric and colorectal cancers, respectively. However, with the development of reliable mouse models and affordable sequencing technologies, the most fascinating aspect of the microbiome-cancer relationship, where microbes undermine cancer immune surveillance and indirectly promote oncogenesis, has only recently been described. In this review, we highlight the essential role of the microbiome in immune system development and maturation. We review how microbe-induced immune activation promotes oncogenesis, focusing particularly on pancreatic carcinogenesis, and show that modulation of the microbiome augments the anti-cancer immune response and enables successful immunotherapy against pancreatic cancer.

NFκB in Pancreatic Stellate Cells Reduces Infiltration of Tumors by Cytotoxic T Cells and Killing of Cancer Cells, via Up-regulation of CXCL12.

BACKGROUND & AIMS: Immunotherapies are ineffective against pancreatic cancer. We investigated whether the activity of nuclear factor (NF)κB in pancreatic stromal cells contributes to an environment that suppresses antitumor immune response. METHODS: Pancreata of C57BL/6 or Rag1-/- mice were given pancreatic injections of a combination of KrasG12D/+; Trp53 R172H/+; Pdx-1cre (KPC) pancreatic cancer cells and pancreatic stellate cells (PSCs) extracted from C57BL/6 (control) or mice with disruption of the gene encoding the NFκB p50 subunit (Nfkb1 or p50-/- mice). Tumor growth was measured as an endpoint. Other mice were given injections of Lewis lung carcinoma (LLC) lung cancer cells or B16-F10 melanoma cells with control or p50-/- fibroblasts. Cytotoxic T cells were depleted from C57BL/6 mice by administration of antibodies against CD8 (anti-CD8), and growth of tumors from KPC cells, with or without control or p50-/- PSCs, was measured. Some mice were given an inhibitor of CXCL12 (AMD3100) and tumor growth was measured. T-cell migration toward cancer cells was measured using the Boyden chamber assay. RESULTS: C57BL/6 mice coinjected with KPC cells (or LLC or B16-F10 cells) and p50-/- PSCs developed smaller tumors than mice given injections of the cancer cells along with control PSCs. Tumors that formed when KPC cells were injected along with p50-/- PSCs had increased infiltration by activated cytotoxic T cells along with decreased levels of CXCL12, compared with tumors grown from KPC cells injected along with control PSCs. KPC cells, when coinjected with control or p50-/- PSCs, developed the same-size tumors when CD8+ T cells were depleted from C57BL/6 mice or in Rag1-/- mice. The CXCL12 inhibitor slowed tumor growth and increased tumor infiltration by cytotoxic T cells. In vitro expression of p50 by PSCs reduced T-cell migration toward and killing of cancer cells. When cultured with cancer cells, control PSCs expressed 10-fold higher levels of CXCL12 than p50-/- PSCs. The CXCL12 inhibitor increased migration of T cells toward KPC cells in culture. CONCLUSIONS: In studies of mice and cell lines, we found that NFκB activity in PSCs promotes tumor growth by increasing expression of CXCL12, which prevents cytotoxic T cells from infiltrating the tumor and killing cancer cells. Strategies to block CXCL12 in pancreatic tumor cells might increase antitumor immunity.

Gut Microbiota Promotes Tumor Growth in Mice by Modulating Immune Response.

We studied the effects of gut microbiome depletion by oral antibiotics on tumor growth in subcutaneous and liver metastases models of pancreatic cancer, colon cancer, and melanoma. Gut microbiome depletion significantly reduced tumor burden in all the models tested. However, depletion of gut microbiome did not reduce tumor growth in Rag1-knockout mice, which lack mature T and B cells. Flow cytometry analyses demonstrated that gut microbiome depletion led to significant increase in interferon gamma-producing T cells with corresponding decrease in interleukin 17A and interleukin 10-producing T cells. Our results suggest that gut microbiome modulation could emerge as a novel immunotherapeutic strategy.

Genetics of pancreatic cyst-cancer progression: standing on the shoulders of giants.

PURPOSE OF REVIEW: Pancreatic cancer, despite years of study and some progress, presents with a grim prognosis in almost all cases. In the current review, we have discussed recent studies that have attempted to decipher the genetic makeup of pancreatic ductal adenocarcinoma and preneoplastic pancreatic cystic neoplasms. RECENT FINDINGS: With the advent of high throughput sequencing, the genetic code of pancreatic cancer is beginning to unravel and this new-found information heralds an era of precision cancer care where treatment will be guided by the genetic code of the neoplasm. Results from these studies have pointed towards the complexity and heterogeneity of the pancreatic cancer genome, provided avenues to "tailor therapy" based as well as shed light on progression of preneoplastic pancreatic neoplasms into full blown invasive pancreatic ductal adenocarcinoma. SUMMARY: While this progress has made us closer to the model of precision medicine, significant obstacles need to be overcome to use this new-found information to change the way we manage patients with pancreatic cancer.

Insights into the Pathogenesis of Pancreatic Cystic Neoplasms.

With the current epidemic of diagnosed pancreatic cystic neoplasms on the rise, a substantial amount of work has been done to unravel their biology, thus leading to implications on clinical decision making. Recent genetic profiling of resected human specimens has identified alterations in signaling pathways involving KRAS and GNAS signaling as early events in the pathogenesis of intraductal pancreatic mucinous neoplasms. Progressively, mutations in genes such as TP53, SMAD4, RNF43, and others are thought to characterize invasive and advanced lesions. The role of inflammation in fueling the growth and transformation of these cysts has also begun to be studied with greater interest. A number of promising clinical studies have attempted to integrate these genetic insights into classifying these cysts and treating patients. We have reviewed existing literature on similar lines besides commenting on some useful animal models that recapitulate molecular and phenotypic progression of these cysts.

"Heat shock protein 70 in pancreatic diseases: Friend or foe".

The heat shock response in pancreatitis that is activated via HSP70 protects acinar cells through multiple simultaneous mechanisms. It inhibits trypsinogen activation and modulates NF-κB signaling to limit acinar cell injury. On the other hand, HSP70 is overexpressed in pancreatic cancer and is hijacked by the cellular machinery to inhibit apoptosis. Inhibition of HSP70 in pancreatic cancer by a novel compound, Minnelide, has shown considerable clinical promise.

Laparoscopic bilateral transperitoneal adrenalectomy for Cushing syndrome: surgical challenges and lessons learnt.

PURPOSE: Laparoscopic adrenalectomy is well established for treatment of adrenal lesions. However, bilateral adrenalectomy for Cushing syndrome is a challenging and time-consuming operation. We report our experience of laparoscopic bilateral adrenalectomy for this disease in 19 patients. MATERIALS AND METHODS: From September 2009 to August 2012, we have operated 19 patients with Cushing syndrome and performed bilateral laparoscopic adrenalectomy using the transperitoneal approach; synchronous in 15 patients and staged in 4 patients. In 15 patients, the surgery was carried out sequentially on both the sides in lateral position with intraoperative change in position. Complete adrenalectomy including periadrenal fat was carried out on both the sides. RESULTS: Nineteen patients were referred from Department of Endocrinology for bilateral adrenalectomy for adrenocorticotropin hormone (ACTH)-dependent and ACTH-independent Cushing syndrome. The indications for surgery were Cushing disease in 15 patients, occult/ectopic source of ACTH in 2 patients, and primary adrenal hyperplasia in 2 patients. Fifteen patients underwent bilateral adrenalectomy during the same operation. Four patients underwent staged procedures. All procedures were completed laparoscopically with no conversions. The mean operating time for simultaneous bilateral adrenalectomy was 210 minutes (range, 150 to 240 min). This included the repositioning and reprepping time. There were no major intraoperative complications. The average blood loss was 100 mL (range, 50 to 200 mL). None of the patients required blood transfusions in the postoperative period. The postoperative complications included minor port-site infection in 2 patients. One severely debilitated patient died on the 14th postoperative day because of hospital-acquired pneumonia. The remaining 18 patients have done well in terms of impact on the disease. CONCLUSIONS: Laparoscopic bilateral adrenalectomy for Cushing syndrome is feasible and safe. It confers all the advantages of minimally invasive approach such as less postoperative pain, shorter hospitalization, lesser wound complications, and faster recovery. The advantages of the laparoscopic approach have led to an earlier referral for bilateral adrenalectomy by endocrinologist in patients with failed pituitary surgery.