Cytoreductive surgery and HIPEC improve survival compared to palliative chemotherapy for biliary carcinoma with peritoneal metastasis: A multi-institutional cohort from PSOGI and BIG RENAPE groups.

BACKGROUND: Peritoneal metastasis from biliary carcinoma (PMC) is associated with poor prognosis when treated with chemotherapy. OBJECTIVE: To evaluate the impact on survival of cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), and compare with conventional palliative chemotherapy for patients with PMC. MATERIAL AND METHODS: A prospective multicenter international database was retrospectively searched to identify all patients with PMC treated with a potentially curative CRS/HIPEC (CRS/HIPEC group). The overall survival (OS) was compared to patients with PMC treated with palliative chemotherapy (systemic chemotherapy group). Survival was analyzed using Kaplan-Meier method and compared with Log-Rank test. RESULTS: Between 1995 and 2015, 34 patients were included in the surgical group, and compared to 21 in the systemic chemotherapy group. In the surgical group, median peritoneal cancer index was 9 (range 3-26), macroscopically complete resection was obtained for 25 patients (73%). There was more gallbladder localization in the surgical group compared to the chemotherapy group (35% vs. 18%, p = 0.001). Median OS was 21.4 and 9.3 months for surgical and chemotherapy group, respectively (p=0.007). Three-year overall survival was 30% and 10% for surgical and chemotherapy group, respectively. CONCLUSION: Treatment with CRS and HIPEC for biliary carcinoma with peritoneal metastasis is feasible and may provide survival benefit when compared to palliative chemotherapy.

RAGE is essential for oncogenic KRAS-mediated hypoxic signaling in pancreatic cancer.

A hypoxic tumor microenvironment is characteristic of many cancer types, including one of the most lethal, pancreatic cancer. We recently demonstrated that the receptor for advanced glycation end products (RAGE) has an important role in promoting the development of pancreatic cancer and attenuating the response to chemotherapy. We now demonstrate that binding of RAGE to oncogenic KRAS facilitates hypoxia-inducible factor 1 (HIF1)α activation and promotes pancreatic tumor growth under hypoxic conditions. Hypoxia induces NF-κB-dependent and HIF1α-independent RAGE expression in pancreatic tumor cells. Moreover, the interaction between RAGE and mutant KRAS increases under hypoxia, which in turn sustains KRAS signaling pathways (RAF-MEK-ERK and PI3K-AKT), facilitating stabilization and transcriptional activity of HIF1α. Knock down of RAGE in vitro inhibits KRAS signaling, promotes HIF1α degradation, and increases hypoxia-induced pancreatic tumor cell death. RAGE-deficient mice have impaired oncogenic KRAS-driven pancreatic tumor growth with significant downregulation of the HIF1α signaling pathway. Our results provide a novel mechanistic link between NF-κB, KRAS, and HIF1α, three potent molecular pathways in the cellular response to hypoxia during pancreatic tumor development and suggest alternatives for preventive and therapeutic strategies.

Role of AMP-activated protein kinase in cross-talk between apoptosis and autophagy in human colon cancer.

Unresectable colorectal liver metastases remain a major unresolved issue and more effective novel regimens are urgently needed. While screening synergistic drug combinations for colon cancer therapy, we identified a novel multidrug treatment for colon cancer: chemotherapeutic agent melphalan in combination with proteasome inhibitor bortezomib and mTOR (mammalian target of rapamycin) inhibitor rapamycin. We investigated the mechanisms of synergistic antitumor efficacy during the multidrug treatment. All experiments were performed with highly metastatic human colon cancer CX-1 and HCT116 cells, and selected critical experiments were repeated with human colon cancer stem Tu-22 cells and mouse embryo fibroblast (MEF) cells. We used immunochemical techniques to investigate a cross-talk between apoptosis and autophagy during the multidrug treatment. We observed that melphalan triggered apoptosis, bortezomib induced apoptosis and autophagy, rapamycin caused autophagy and the combinatorial treatment-induced synergistic apoptosis, which was mediated through an increase in caspase activation. We also observed that mitochondrial dysfunction induced by the combination was linked with altered cellular metabolism, which induced adenosine monophosphate-activated protein kinase (AMPK) activation, resulting in Beclin-1 phosphorylated at Ser 93/96. Interestingly, Beclin-1 phosphorylated at Ser 93/96 is sufficient to induce Beclin-1 cleavage by caspase-8, which switches off autophagy to achieve the synergistic induction of apoptosis. Similar results were observed with the essential autophagy gene, autophagy-related protein 7, -deficient MEF cells. The multidrug treatment-induced Beclin-1 cleavage was abolished in Beclin-1 double-mutant (D133A/D146A) knock-in HCT116 cells, restoring the autophagy-promoting function of Beclin-1 and suppressing the apoptosis induced by the combination therapy. These observations identify a novel mechanism for AMPK-induced apoptosis through interplay between autophagy and apoptosis.

Inhibitors of C5 complement enhance vaccinia virus oncolysis.

Genetically engineered tumor-selective vaccinia virus (VV) has been demonstrated to be a highly effective oncolytic agent, but immune clearance may limit its therapeutic potential. As previously demonstrated, immunosuppression can lead to significant enhancement of viral recovery and therapeutic effect, but the magnitude of complement-mediated viral inactivation has not been fully elucidated and warrants further investigation. Using fluorescent microscopy and quantitative plaque assays, we have determined complement's key role in viral clearance and its multi-faceted means to pathogen destruction. Complement can lead to direct viral destruction and inhibition of viral uptake into cells, even in the absence of anti-vaccinia antibodies. Our data demonstrate C5 to be integral to the clearance pathway, and its inhibition by Staphylococcal superantigen-like protein leads to a 90-fold and 150-fold enhancement of VV infectivity in both the presence and absence of anti-VV antibodies, respectively. This study suggests that complement inhibition may reduce vaccinia viral neutralization and may be critical to future in vivo work.

A phase I trial of isolated hepatic perfusion (IHP) using 5-FU and oxaliplatin in patients with unresectable isolated liver metastases from colorectal cancer.

BACKGROUND: Isolated hepatic perfusion (IHP) with melphalan is an established approach for patients with unresectable metastatic liver lesions. This study determined the safety and maximum tolerated dose (MTD) of 5-FU with oxaliplatin via IHP. METHODS: Standard 3 × 3 Phase I design. Subjects with unresectable isolated CRC liver metastases scheduled for HAI pump were eligible. IHP used fixed-dose oxaliplatin with escalating 5-FU doses. Toxicity (CTCAE v 4.0) and response (RECIST), progression-free survival, and overall survival (OS) were assessed. Systemic and IHP plasma PK of 5-FU, anabolites, and platinum were determined. RESULTS: All 12 patients had received ≥ 1 line of pre-IHP chemotherapy. There were 4 grade 3 serious adverse events (33.3 %) and 1 grade 4 event (8.3 %). Also, 2 dose-limiting toxicities occurred at DL2 at 300 mg/m(2), resulting in expansion of DL1 at 200 mg/m(2) 5-FU, the eventual MTD. At 6-month follow-up, 9 patients (82 %) demonstrated partial response, while 2 (18 %) exhibited stable disease. Also, 64 % of patients demonstrated a >50 % decrease in CEA. The 1- and 2-year OS probabilities were 90.9 and 71.6 %, respectively, with median follow-up of 24 months. IHP exposures (AUC0-60 min) were 10.9 ± 4.5 µgPt h/mL, 49.3 ± 30.7 µg h/mL 5-FU (DL1), and 70.5 ± 35.5 µg h/mL 5-FU (DL2). Systemic exposure (AUC0-inf) relative to IHP exposure was negligible for both platinum (1.1 ± 1.5 %) and 5-FU (0.09 ± 0.10 %). CONCLUSIONS: The MTD for IHP was 200 mg/m(2) 5-FU with 40 mg/m(2) oxaliplatin. Systemic exposure to the agents was minimal during IHP. The response and survival observed warrants assessment in a larger phase II trial.

Oncolytic poxvirus armed with Fas ligand leads to induction of cellular Fas receptor and selective viral replication in FasR-negative cancer.

Tumor necrosis factor superfamily members, including Fas ligand and TRAIL, have been studied extensively for cancer therapy, including as components of gene therapy. We examined the use of FasL expression to achieve tumor-selective replication of an oncolytic poxvirus (vFasL), and explored its biology and therapeutic efficacy for FasR- and FasR+ cancers. Infection of FasR+ normal and MC38 cancer cells by vFasL led to abortive viral replication owing to acute apoptosis and subsequently showed both reduced pathogenicity in non-tumor-bearing mice and reduced efficacy in FasR+ tumor-bearing mice. Infection of FasR- B16 cancer cells by vFasL led to efficient viral replication, followed by late induction of FasR and subsequent apoptosis. Treatment with vFasL as compared with its parental virus (vJS6) led to increased tumor regression and prolonged survival of mice with FasR- cancer (B16) but not with FasR+ cancer (MC38). The delayed induction of FasR by viral infection in FasR- cells provides for potential increased efficacy beyond the limit of the direct oncolytic effect. FasR induction provides one mechanism for tumor-selective replication of oncolytic poxviruses in FasR- cancers with enhanced safety. The overall result is both a safer and more effective oncolytic virus for FasR- cancer.

A current update on the evolution of robotic liver surgery.

Laparoscopic liver surgery has evolved significantly over the past decade. Increasing understanding of hepatic anatomy and advancements in technology have extended the scope of the minimally invasive approach. Robotic-assisted technology offers solutions to the fundamental limitations of conventional laparoscopic liver resection. Several centers have begun to utilize robotic technology to perform complex liver surgeries. The purpose of this review is to provide a comprehensive analysis of published literature about the role of robotic-assisted laparoscopic technology in liver surgery. A literature search of Pubmed was used to identify all English publications about robotic liver surgery. Publications were selected to examine all unique patient series. Outcomes analyzed included operative time, estimated blood loss, length of stay, complication rate, conversion rate to open, cost, and oncologic outcomes. A total of eight series containing 134 unique patients were selected for review. Sixty-nine percent of patients had malignant lesions resected, while 31% had benign lesions. Segmentectomy/wedge (36%) was the most common resection performed, followed by left lateral sectionectomy (28%) right hepatectomy (16%) and left hepatectomy (9%). A meta-analysis of the remaining data was not possible due to heterogeneity in methods for reporting. Outcomes varied widely between studies. Based on analysis of early published series, robotic liver surgery is a feasible and safe tool for the minimally invasive resection of hepatic lesions. Further evaluation is required to assess for improvement in outcomes, and long-term oncologic outcomes are still pending.

The combination of immunosuppression and carrier cells significantly enhances the efficacy of oncolytic poxvirus in the pre-immunized host.

Pre-existing antipoxvirus immunity in cancer patients presents a severe barrier to poxvirus-mediated oncolytic virotherapy. We have explored strategies of immunosuppression (IS) and/or immune evasion for efficient delivery of an oncolytic double-deleted vaccinia virus (vvDD) to tumors in the pre-immunized mice. Transient IS using immunosuppressive drugs, including tacrolimus, mycophenolate mofetil and methylprednisolone sodium succinate, have been used successfully in organ transplantation. This drug cocktail alone did not enhance viral recovery from subcutaneous tumor after systemic viral delivery. Using B-cell knockout mice, we confirmed that the neutralizing antibodies had a significant role in preventing poxvirus infection. Using a MC38 peritoneal carcinomatosis model, we found that the combination of IS and tumor cells as carriers led to the most effective viral delivery, viral replication and viral spread inside the tumor mass. We found that our immunosuppressive drug cocktail facilitated recruitment of tumor-associated macrophages and conversion into an immunosuppressive M2 phenotype (interleukin (IL)-10(hi)/IL-12(low)) in the tumor microenvironment. A combination of IS and carrier cells led to significantly prolonged survival in the tumor model. These results showed the feasibility of treating pre-vaccinated patients with peritoneal carcinomatosis using an oncolytic poxvirus and a combined immune intervention strategy.

TRAIL gene-armed oncolytic poxvirus and oxaliplatin can work synergistically against colorectal cancer.

We have explored a unique combination therapy for metastatic colorectal cancer. This strategy combines a potent and new oncolytic poxvirus expressing a membrane-bound tumor necrosis factor-related apoptosis-inducing ligand (TRAIL or TNFSF10) and oxaliplatin (Ox) chemotherapy. We hypothesized that TRAIL expression would increase the efficacy of the oncolytic poxvirus, and that the therapeutic efficacy would be further enhanced by combination with chemotherapy. The cytotoxicity to cancer cells by Ox, oncolytic vaccinia virus (VV) and trail gene-armed VV alone or in combination was tested in vitro. The trail gene armed oncolytic VV-expressed high levels of TRAIL in infected cancer cells and had greater potency as a cytotoxic agent compared with the parent VV. Ox alone exerted concentration-dependent cytotoxicity. In vitro, the combination of the two agents applied at suboptimal concentrations for individual therapy displayed synergy in inducing cancer cells into enhanced levels of apoptosis/necrosis. Western blot analyses were consistent with the notion that TRAIL induced cancer cell death mainly through apoptosis, whereas Ox and vJS6 induced cell death more through non-apoptotic death pathways. In two aggressive colorectal carcinomatosis models derived from human HCT116 and murine MC38 cells, the combination therapy displayed synergistic or additive antitumor activity and prolonged the survival of the tumor-bearing mice compared with either Ox chemotherapy or vvTRAIL-mediated oncolytic gene therapy alone. This combination strategy may provide a new avenue to treating peritoneal carcinomatosis and other types of metastases of colorectal cancer.

Surgical management of leiomyosarcoma of the inferior vena cava.

INTRODUCTION: Leiomyosarcoma of the inferior vena cava (IVC) is a rare tumor for which en bloc resection offers the only chance of cure. Due to its rarity, however, optimal strategies for the management of the primary tumor and subsequent recurrences are not well defined. METHODS: We performed a retrospective review of patients who underwent surgical resection of IVC leiomyosarcoma. We evaluated clinical presentations, operative techniques, patterns of recurrence and survival. RESULTS: From 1990 to 2008, nine patients (four females) were identified. Median age was 55 years (40-76). Presentations included abdominal pain (n = 5), back pain (n = 2), leg swelling (n = 4) and abdominal mass (n = 2). Pre-operative imaging studies showed tumor location to be from the right atrium to renal veins (n = 1), retrohepatic (n = 5), and from hepatic veins to the iliac bifurcations (n = 3). En bloc resection included right nephrectomy (n = 5), right adrenalectomy (n = 4), pancreaticoduodenectomy (n = 1), right hepatic trisectionectomy (n = 1) and right hemicolectomy (n = 1). The IVC was ligated in six patients, and a prosthetic graft was used for IVC reconstruction in three patients. Resection margins were negative in seven cases. Median length of stay was 12 days (range, 6-22 days). Major morbidity included renal failure (n = 1) and there was one post-operative mortality. Five patients had leg edema post-operatively, four of whom had IVC ligation. Median survival was 47 months (range, 1-181 months). Four patients had recurrence and the median time to recurrence was 14 months (range, 3-25 months). Two patients underwent successful resection of recurrence. CONCLUSIONS: Curative resection of IVC leiomyosarcoma can lead to long-term survival. However, recurrence is common, and effective adjuvant treatments are needed. In selected cases, aggressive surgical treatment of recurrence should be considered.

JNK-deficiency enhanced oncolytic vaccinia virus replication and blocked activation of double-stranded RNA-dependent protein kinase.

Vaccinia virus has recently been used as an expression vector for gene delivery and an oncolytic agent for cancer therapy. Although it has been established that interferon-induced double-stranded RNA (dsRNA)-activated protein kinase (PKR) and RNase L interfere with viral replication, little else is known about the other host factors that might affect viral replication and virus-mediated host cell killing. In this study, we evaluated the roles of c-Jun NH2-terminal kinase (JNK) in oncolytic vaccinia virus replication and vaccinia virus-mediated host cell killing. We found that JNK knockout mouse embryonic fibroblasts (MEFs) were more susceptible to oncolytic vaccinia virus infection than wild-type MEFs. Moreover, viral replication and the production of infectious viral progeny were up to 100-fold greater in JNK-deficient MEFs than in wild-type MEFs. A similar result was observed for wild-type vaccinia virus. The increased killing of infected cells and the production of viral progeny was also observed in wild-type MEFs that had been treated with JNK inhibitors and in human colon cancer cells that had been transfected with dominant-negative JNK constructs. Moreover, testing on several human lung cancer cell lines and HeLa cells showed an inverse correlation between levels of JNK expression and susceptibility to oncolytic vaccinia virus. Our study also revealed that oncolytic virus infection-mediated PKR activation was blocked or diminished in JNK-deficient MEFs. The adenovirus-mediated ectopic expression of human PKR in JNK-deficient MEFs reduced vaccinia virus replication to the levels observed in wild-type MEFs, indicating that JNK is required for vaccinia virus to efficiently activate PKR. Our results demonstrated that the cellular status of JNK function can dramatically affect oncolytic vaccinia virus replication and vaccinia virus-mediated host cell killing. This finding may enable further improvements in oncolytic virotherapy using vaccinia virus.

Oncolytic virotherapy for ovarian carcinomatosis using a replication-selective vaccinia virus armed with a yeast cytosine deaminase gene.

In this study, we assessed the ability of a highly tumor-selective oncolytic vaccinia virus armed with a yeast cytosine deaminase gene to infect and lyse human and murine ovarian tumors both in vitro and in vivo. The virus vvDD-CD could infect, replicate in and effectively lyse both human and mouse ovarian cancer cells in vitro. In two different treatment schedules involving either murine MOSEC or human A2780 ovarian carcinomatosis models, regional delivery of vvDD-CD selectively targeted tumor cells and ovarian tissue, effectively delaying the development of either tumor or ascites and leading to significant survival advantages. Oncolytic virotherapy using vvDD-CD in combination with the prodrug 5-fluorocytosine conferred an additional long-term survival advantage upon tumor-bearing immunocompetent mice. These findings demonstrate that a tumor-selective oncolytic vaccinia combined with gene-directed enzyme prodrug therapy is a highly effective strategy for treating advanced ovarian cancers in both syngeneic mouse and human xenograft models. Given the biological safety, tumor selectivity and oncolytic potency of this armed oncolytic virus, this dual therapy merits further investigation as a promising new treatment for metastatic ovarian cancer.

A new recombinant vaccinia with targeted deletion of three viral genes: its safety and efficacy as an oncolytic virus.

To enhance further the safety and efficacy of oncolytic vaccinia virus, we have developed a new virus with targeted deletions of three viral genes encoding thymidine kinase and antiapoptotic/host range proteins SPI-1 and SPI-2 (vSPT). Infection of human and murine tumor cell lines yielded nearly equivalent or a log lower virus recovery in comparison to parental viruses. Viral infection activated multiple caspases in cancer cells but not in normal cells, suggesting infected cells may die via different pathways. In tumor-bearing mice, vSPT recovery from MC38 tumor was slightly reduced in comparison to two parental viruses. However, no virus was recovered from the brains and livers of mice injected with vSPT in contrast to control viruses. vSPT demonstrated significantly lower pathogenicity in nude mice. Systemic delivery of vSPT showed significant tumor inhibition in subcutaneous MC38 tumor, human ovarian A2780 and murine ovarian MOSEC carcinomatosis models; however, the tumor inhibition by vSPT was reduced compared with parental viruses. These results demonstrated that although deletion of these three viral genes further enhanced tumor selectivity, it also weakened the oncolytic potency. This study illustrates the complexity of creating a tumor-selective oncolytic virus by deleting multiple viral genes involved in multiple cellular pathways.

Influenza vaccination coverage among children aged 6-23 months - six immunization information system sentinel sites, United States, 2005-06 influenza season.

Beginning with the 2004-05 influenza season, the Advisory Committee on Immunization Practices (ACIP) recommended that all children aged 6-23 months receive influenza vaccinations annually. Other children recommended to receive influenza vaccinations include those aged 6 months-18 years who have certain high-risk medical conditions, those on chronic aspirin therapy, those who are household contacts of persons at high risk for influenza complications, and, since 2006, all children aged 24-59 months. Previously unvaccinated children aged <9 years need 2 doses administered at least 1 month apart to be considered fully vaccinated. This report assesses influenza vaccination coverage among children aged 6-23 months during the 2005-06 influenza season by using data from six immunization information system (IIS) sentinel sites. The findings demonstrate that vaccination coverage with 1 or more doses varied widely (range: 6.6% to 60.4%) among sites, with coverage increasing from the preceding influenza season in four of the six sites. However, <23% of children in five of the sites were fully vaccinated, underscoring the need for increased measures to improve the proportion of children who are fully vaccinated.

Reoperation for hyperparathyroidism in multiple endocrine neoplasia type 1.

BACKGROUND: Patients with multiple endocrine neoplasia type 1 and hyperparathyroidism often undergo multiple operations because of inadequate initial surgery, presence of supernumerary and ectopic glands, regrowth of remnant glands, or autograft hyperfunction. Management of this patient population is complex. METHODS: From January 1975 to December 2000 we performed 94 reoperative parathyroidectomies consisting of 79 neck reexplorations, 12 autograft removals, and 3 median sternotomies in 75 patients. Data were gathered by retrospective chart review and follow-up telephone interviews. RESULTS: Excluding autograft excision, reoperative surgery was successful (normocalcemia longer than 6 months) in 91%; autograft removal was successful in only 58%. With a median follow-up of 59 months, 64% of patients are currently free from hypercalcemia, and this outcome was not influenced by the total number of glands resected. The median time to recurrent hypercalcemia was 125 months. Thirty patients received an autograft after reoperation. The complication rate for all reoperations was 12%, including permanent recurrent laryngeal nerve injury in 2 patients (2.1%). CONCLUSIONS: Reoperative parathyroidectomy in patients with multiple endocrine neoplasia type 1 was safe and successful in the majority of patients; however, recurrent hyperparathyroidism is likely to develop in most individuals beyond 10 years of follow-up. The total number of glands accounted for after reoperation is not associated with successful outcome.

Systemic cancer therapy with a tumor-selective vaccinia virus mutant lacking thymidine kinase and vaccinia growth factor genes.

We have demonstrated previously the oncolytic effects of a systemically delivered, replicating vaccinia virus. To enhance the tumor specificity of this vector, we have developed a combined thymidine kinase-deleted (TK-) and vaccinia growth factor-deleted (VGF-) vaccinia virus and investigated its properties in vitro and in vivo. The gene for enhanced green fluorescent protein (EGFP) was inserted into the TK locus of a VGF- vaccinia virus by homologous recombination creating a double-deleted mutant vaccinia virus (vvDD-GFP). Infection of resting and dividing NIH3T3 cells with vvDD-GFP yielded reduced viral recovery compared with wild-type (WT), TK-, or VGF- viruses from resting cultures but equivalent virus recovery from dividing cultures. Eight days after nude mice were injected i.p. with 10(7) plaque-forming units (pfu) of WT, TK-, VGF-, or vvDD-GFP vaccinia virus, tissues and tumor were harvested for viral titer determination. No virus was recovered from the brains of mice injected with vvDD-GFP compared with the other viruses, which ranged from 130 to 28,000 pfu/mg protein; however, equivalent amounts were recovered from tumor. There was no toxicity from vvDD-GFP because nude mice receiving 10(8) pfu of IP vvDD-GFP lived >100 days, whereas mice receiving WT, VGF-, or TK- virus had median survivals of only 6, 17, and 29 days, respectively. Similar results were seen when 10(9) pfu of vvDD-GFP were given. Nude mice bearing s.c. murine colon adenocarcinoma (MC38) had significant tumor regression after treatment with 10(9) pfu of systemic (i.p.) vvDD-GFP compared with control (mean tumor size, 180.71 +/- 35.26 mm(3) versus 2796.79 +/- 573.20 mm(3) 12 days after injection of virus). Our data demonstrate that a TK- and VGF- mutant vaccinia virus is significantly attenuated in resting cells in vitro and demonstrates tumor-specific replication in vivo. It is a promising vector for use in tumor-directed gene therapy, given its enhanced safety profile, tumor selectivity, and the oncolytic effects after systemic delivery.

Yaba-like disease virus: an alternative replicating poxvirus vector for cancer gene therapy.

Vaccinia virus is being investigated as a replicating vector for tumor-directed gene therapy. However, the majority of cancer patients have preformed immunologic reactivity against vaccinia virus, as a result of smallpox vaccination, which may limit its use as a vector. The Yaba-like disease (YLD) virus was investigated here as an alternative, replicating poxvirus for cancer gene therapy. We have demonstrated that the YLD virus does not cross-react with vaccinia virus antibodies, and it replicates efficiently in human tumor cells. YLD virus can be expanded and purified to high titer in CV-1 cells under conditions utilized for vaccinia virus. The YLD virus RNA polymerase was able to express genes regulated by a synthetic promoter designed for use in orthopoxviruses. We sequenced the YLD virus TK gene and created a shuttle plasmid, which allowed the recombination of the green fluorescent protein (GFP) gene into the YLD virus. In a murine model of ovarian cancer, up to 38% of cells in the tumor expressed the GFP transgene 12 days after intraperitoneal virus delivery. YLD virus has favorable characteristics as a vector for cancer gene therapy, and this potential should be explored further.

A prospective analysis of plasma endostatin levels in colorectal cancer patients with liver metastases.

BACKGROUND: Circulating inhibitors of angiogenesis have been suggested to affect the growth of distant micrometastatic disease in patients with cancer. This study was designed to evaluate circulating endostatin levels in colorectal cancer patients with liver metastases. METHODS: Plasma samples from 30 colorectal cancer patients with liver metastases were analyzed for endostatin and vascular endothelial growth factor (VEGF) by using competitive enzyme immunoassays. Samples were compared with plasma from age- and sex-matched healthy controls; values >2 SD above the control mean were considered elevated. RESULTS: Plasma endostatin levels were significantly higher in the 30 cancer patients than controls (P < .0001) and correlated with preoperative VEGF levels (P = .0008). Eighteen patients underwent surgical treatment (liver resection, n = 10; or isolated hepatic perfusion with melphalan, n = 8). Seventeen treated patients were available for follow-up. Eight of 11 patients who progressed had elevated plasma endostatin levels at the time of progression. None of six patients who remained progression free had elevated endostatin levels at last follow-up (P = .02). CONCLUSIONS: Plasma endostatin levels are elevated in colorectal cancer patients with liver metastases and correlate with VEGF levels. Elevated endostatin levels during follow-up are associated with disease progression. Understanding the role of endogenous endostatin in cancer patients may lead to novel strategies to inhibit tumor angiogenesis.