GLDC promotes colorectal cancer metastasis through epithelial-mesenchymal transition mediated by Hippo signaling pathway

Cancer metastasis remains a major cause of death in cancer patients, and epithelial-mesenchymal transition (EMT) plays a decisive role in cancer metastasis. Recently, abnormal expression of Glycine Decarboxylase (GLDC) has been demonstrated in tumor progression, and GLDC is up-regulated in cancers, such as lung, prostate, bladder, and cervical cancers. However, the exact role of GLDC in colorectal cancer (CRC) progression remains to be elucidated. The aim of our study was to explore the role of GLDC in CRC metastasis. The GSE75117 database was used to investigate GLDC expression in tumor center and invasive front tissues and we found that GLDC expression levels were higher in the invasive front tissue. GLDC expression levels were negatively correlated with the prognosis of CRC patients. In vitro studies have showed that GLDC can promote invasion and migration of CRC cells by inhibiting the Hippo signaling pathway and regulating the EMT process. Blocking the Hippo signaling pathway with Verteporfin reduced the effect of GLDC on CRC metastasis. In vivo metastasis assays further confirmed that tail vein injection of GLDC+/+ cells induced more lung metastasis, compared to normal CRC cells. The results of this study suggest that GLDC promotes EMT through the Hippo signaling pathway, providing a new therapeutic target for CRC metastasis.

Cancer Cells Promote Phenotypic Alterations in Hepatocytes at the Edge of Cancer Cell Nests to Facilitate Vessel Co-Option Establishment in Colorectal Cancer Liver Metastases

Simple Summary

Tumour cells in colorectal cancer liver metastases (CRCLM) obtain their blood supply via two major mechanisms: (i) sprouting angiogenesis, through the generation of new vessels; (ii) vessel co-option, where the cancer cells hijack the pre-existing vasculature. The current treatment for CRCLM targets angiogenesis; however, these treatments are ineffective on cancer cells utilizing vessel co-option to gain their blood supply. Our study suggests that cancer cells stimulate phenotypic alterations in the cells of surrounding liver tissue (hepatocytes) in vessel co-opting lesions. These modifications facilitate cancer cells to infiltrate through the liver tissue and hijack the pre-existing vasculature to obtain oxygen and nutrients.

Abstract

Vessel co-option is correlated with resistance against anti-angiogenic therapy in colorectal cancer liver metastases (CRCLM). Vessel co-opting lesions are characterized by highly motile cancer cells that move toward and along the pre-existing vessels in the surrounding nonmalignant tissue and co-opt them to gain access to nutrients. To access the sinusoidal vessels, the cancer cells in vessel co-opting lesions must displace the hepatocytes and occupy their space. However, the mechanisms underlying this displacement are unknown. Herein, we examined the involvement of apoptosis, autophagy, motility, and epithelial–mesenchymal transition (EMT) pathways in hepatocyte displacement by cancer cells. We demonstrate that cancer cells induce the expression of the proteins that are associated with the upregulation of apoptosis, motility, and EMT in adjacent hepatocytes in vitro and in vivo. Accordingly, we observe the upregulation of cleaved caspase-3, cleaved poly (ADP-ribose) polymerase-1 (PARP-1) and actin-related protein 2/3 (ARP2/3) in adjacent hepatocytes to cancer cell nests, while we notice a downregulation of E-cadherin. Importantly, the knockdown of runt-related transcription factor 1 (RUNX1) in cancer cells attenuates the function of cancer cells in hepatocytes alterations in vitro and in vivo. Altogether, our data suggest that cancer cells exploit various mechanisms to displace hepatocytes and access the sinusoidal vessels to establish vessel co-option.

Angiopoietin1 Deficiency in Hepatocytes Affects the Growth of Colorectal Cancer Liver Metastases (CRCLM)

Colorectal cancer liver metastases (CRCLM) that receive their blood supply via vessel co-option are associated with a poor response to anti-angiogenic therapy. Angiopoietins (Ang1 and Ang2) with their Tyrosine-protein kinase receptor (Tie2) have been shown to support vessel co-option. We demonstrate significantly higher expression of Ang1 in hepatocytes adjacent to the tumor region of human chemonaïve and treated co-opting (replacement histopathological growth patterns: RHGP) tumors. To investigate the role of the host Ang1 expression, Ang1 knockout (KO) mice were injected intra-splenically with metastatic MC-38 colon cancer cells that develop co-opting liver metastases. We observed a reduction in the number of liver metastases and interestingly, for the first time, the development of angiogenic driven desmoplastic (DHGP) liver metastases. In addition, in-vitro, knockout of Ang1 in primary hepatocytes inhibited viability, migration and invasion ability of MC-38 cells. We also demonstrate that Ang 1 alone promotes the migration and growth of both human and mouse colon cancer cell lines These results provide evidence that high expression of Ang1 in the host liver is important to support vessel co-option (RHGP lesions) and when inhibited, favours the formation of angiogenic driven liver metastases (DHGP lesions).

Survival and Prognostic Factors of Colorectal Liver Metastases After Surgical and Nonsurgical Treatment

OBJECTIVE

Colorectal cancer is one leading cause of cancer-related death worldwide, and distant metastases determine an unfavorable prognosis. Surgical resection of colorectal liver metastases (CRLM) improves survival and provides the chance for cure. The aim of this study was to prospectively analyze the outcome of patients with CRLM in a population-based manner, and thereby, to compare the prognosis of patients undergoing resection with those receiving nonsurgical treatment. Moreover, we set out to identify and confirm important prognostic factors after resection of CRLM.

PATIENTS AND METHODS

We analyzed the outcome of 506 patients diagnosed with CRLM in our institution from 1996 to 2011. Survival and the impact of clinical and pathologic factors were analyzed by univariate analysis. Important independent prognostic factors were analyzed by multivariate analysis.

RESULTS

The 5-year overall survival rate (5y-OSR) for patients receiving resection of CRLM (n = 152) was 46% (95% confidence interval (CI), 37%-54%) compared with a 5y-OSR of 6% (95% CI, 4%-9%) for patients treated nonsurgically (n = 354). There was no perioperative mortality. Multivariate analysis revealed, among other factors, good performance status of the patient (low American Society of Anesthesiologists score), the absence of extrahepatic metastases, < 5 metastatic lesions, and a tumor-free resection margin (R0) as important, independent prognostic factors. Importantly, repeated hepatic resections of CRLM performed in 13 patients were associated with an excellent outcome (5y-OSR, 47%; 95% CI, 17%-72%).

CONCLUSION

Surgical resection, which can be performed with tolerable site-effects, is the first choice for patients diagnosed with metachronous and synchronous CRLM. Of note, repeated resections should be advised in recurrent intrahepatic colorectal cancer whenever possible.

Hobson's choice two-stage hepatectomy for multiple and bilobar colorectal liver metastases with portal vein embolization: report of two cases

Liver resection is recognized as the preferred treatment for patients with colorectal liver metastases (CLM) because it offers long-term survival; it is the only hope for a cure. However, in the majority of cases, liver surgery is contraindicated due to the small volume of the future remnant liver. To extend the surgical indications for CLM, a planned two-stage hepatectomy procedure with portal vein embolization (PVE) was developed specifically for patients with multiple and bilobar CLM. The rationale for performing the procedure was a concern about the possible overgrowth of intrafuture remnant liver lesions following PVE, and it was therefore recommended for all multiple bilobar CLM cases, even when one-stage hepatectomy was technically feasible. We recently performed Hobson's choice two-stage hepatectomy in two cases for reasons different from those of the original planned two-stage hepatectomy. In the present report, we describe our Hobson's choice two-stage hepatectomy strategy, which provided favorable short-term outcomes.

Blockade of the renin-angiotensin system inhibits growth of colorectal cancer liver metastases in the regenerating liver

Partial hepatectomy (PH), the preferred option for selected patients with colorectal cancer liver metastases (CRCLM), is associated with 40-80% tumor recurrence rates. Renin-angiotensin system (RAS) blockade inhibits tumor growth and has been suggested to improve liver regeneration. We documented the effect of RAS blockade on tumor growth and liver regeneration in a murine model. CRCLM induction followed by 70% PH was performed on 78 CBA mice. Liver regeneration (days 2, 6) and CRCLM tumor load were measured by liver (and tumor) weights, percentage of CRCLM burden and tumor nodule count (days 16, 21). mRNA expression of the RAS components was characterised. Statistical analysis was performed using 2-independent sample T test or Mann-Whitney test (SPSS). Captopril did not impair liver regeneration. By day 21, Captopril decreased tumor burden (percentage of CRCLM in the liver) (48.7 ± 4.7% control, 24.4 ± 6.2 Captopril; p = 0.008), tumor volume (1046.2 ± 200.2 mm(3), 388.3 ± 150.4; p = 0.02), tumor nodule count per image field (181.1 ± 28.5, 68 ± 17.6; p = 0.005) and tumor angiogenesis (71.8 ± 6.4 vessels/mm(2), 43.1 ± 7.6; p = 0.015) compared to controls. Captopril enhanced tumor apoptosis (1 ± 0.2%, 2.5 ± 0.7; p = 0.028). Liver regeneration and tumor development increased liver ACE levels. Blockade of the RAS effectively retarded CRCLM tumor growth at the late stage of tumor development within the regenerating liver without impeding liver regeneration following PH, via anti-angiogenesis and pro-tumor apoptosis. Captopril may be of therapeutic benefit in patients undergoing PH for CRCLM.

Differential expression of colon cancer associated transcript1 (CCAT1) along the colonic adenoma-carcinoma sequence

BACKGROUND

The transition from normal epithelium to adenoma and, to invasive carcinoma in the human colon is associated with acquired molecular events taking 5-10 years for malignant transformation. We discovered CCAT1, a non-coding RNA over-expressed in colon cancer (CC), but not in normal tissues, thereby making it a potential disease-specific biomarker. We aimed to define and validate CCAT1 as a CC-specific biomarker, and to study CCAT1 expression across the adenoma-carcinoma sequence of CC tumorigenesis.

METHODS

Tissue samples were obtained from patients undergoing resection for colonic adenoma(s) or carcinoma. Normal colonic tissue (n = 10), adenomatous polyps (n = 18), primary tumor tissue (n = 22), normal mucosa adjacent to primary tumor (n = 16), and lymph node(s) (n = 20), liver (n = 8), and peritoneal metastases (n = 19) were studied. RNA was extracted from all tissue samples, and CCAT1 expression was analyzed using quantitative real time-PCR (qRT-PCR) with confirmatory in-situ hybridization (ISH).

RESULTS

Borderline expression of CCAT1 was identified in normal tissue obtained from patients with benign conditions [mean Relative Quantity (RQ) = 5.9]. Significant relative CCAT1 up-regulation was observed in adenomatous polyps (RQ = 178.6 ± 157.0; p = 0.0012); primary tumor tissue (RQ = 64.9 ± 56.9; p = 0.0048); normal mucosa adjacent to primary tumor (RQ = 17.7 ± 21.5; p = 0.09); lymph node, liver and peritoneal metastases (RQ = 11,414.5 ± 12,672.9; 119.2 ± 138.9; 816.3 ± 2,736.1; p = 0.0001, respectively). qRT-PCR results were confirmed by ISH, demonstrating significant correlation between CCAT1 up-regulation measured using these two methods.

CONCLUSION

CCAT1 is up-regulated across the colon adenoma-carcinoma sequence. This up-regulation is evident in pre-malignant conditions and through all disease stages, including advanced metastatic disease suggesting a role in both tumorigenesis and the metastatic process.

Cell budding from normal appearing epithelia: a predictor of colorectal cancer metastasis?

Background: Colorectal carcinogenesis is believed to be a multi-stage process that originates with a localized adenoma, which linearly progresses to an intra-mucosal carcinoma, to an invasive lesion, and finally to metastatic cancer. This progression model is supported by tissue culture and animal model studies, but it is difficult to reconcile with several well-established observations, principally among these are that up to 25% of early stage (Stage I/II), node-negative colorectal cancer (CRC) develop distant metastasis, and that circulating CRC cells are undetectable in peripheral blood samples of up to 50% of patients with confirmed metastasis, but more than 30% of patients with no detectable metastasis exhibit such cells. The mechanism responsible for this diverse behavior is unknown, and there are no effective means to identify patients with pending, or who are at high risk for, developing metastatic CRC.

Novel findings: Our previous studies of human breast and prostate cancer have shown that cancer invasion arises from the convergence of a tissue injury, the innate immune response to that injury, and the presence of tumor stem cells within tumor capsules at the site of the injury. Focal degeneration of a capsule due to age or disease attracts lymphocyte infiltration that degrades the degenerating capsules resulting in the formation of a focal disruption in the capsule, which selectively favors proliferating or “budding” of the underlying tumor stem cells. Our recent studies suggest that lymphocyte infiltration also triggers metastasis by disrupting the intercellular junctions and surface adhesion molecules within the proliferating cell buds causing their dissociation. Then, lymphocytes and tumor cells are conjoined through membrane fusion to form tumor-lymphocyte chimeras (TLCs) that allows the tumor stem cell to avail itself of the lymphocyte's natural ability to migrate and breach cell barriers in order to intravasate and to travel to distant organs. Our most recent studies of human CRC have detected nearly identical focal capsule disruptions, lymphocyte infiltration, budding cells, and the formation of TLCs. Our studies have further shown that age- and type-matched node-positive and -negative CRC have a significantly different morphological and immunohistochemical profile and that the majority of lymphatic ducts with disseminated cells are located within the mucosa adjacent to morphologically normal appearing epithelial structures that express a stem cell-related marker.

New hypothesis: Based on these findings and the growth patterns of budding cells revealed by double immunohistochemistry, we further hypothesize that metastatic spread is an early event of carcinogenesis and that budding cells overlying focal capsule disruptions represent invasion- and metastasis-initiating cells that follow one of four pathways to progress: (1) to undergo extensive in situ proliferation leading to the formation of tumor nests that subsequently invade the submucosa, (2) to migrate with associated lymphocytes functioning as “seeds” to grow in new sites, (3) to migrate and intravasate into pre-existing vascular structures by forming TLCs, or (4) to intravasate into vascular structures that are generated by the budding cells themselves. We also propose that only node-positive cases harbor stem cells with the potential for multi-lineage differentiation and unique surface markers that permit intravasation.

Tumor-infiltrating immune cells promoting tumor invasion and metastasis: existing theories

It is a commonly held belief that infiltration of immune cells into tumor tissues and direct physical contact between tumor cells and infiltrated immune cells is associated with physical destructions of the tumor cells, reduction of the tumor burden, and improved clinical prognosis. An increasing number of studies, however, have suggested that aberrant infiltration of immune cells into tumor or normal tissues may promote tumor progression, invasion, and metastasis. Neither the primary reason for these contradictory observations, nor the mechanism for the reported diverse impact of tumor-infiltrating immune cells has been elucidated, making it difficult to judge the clinical implications of infiltration of immune cells within tumor tissues. This mini-review presents several existing hypotheses and models that favor the promoting impact of tumor-infiltrating immune cells on tumor invasion and metastasis, and also analyzes their strength and weakness.

Tube-like structures with co-expression of D2-40 and CD34: newly formed vasculatures?

Background: A great number of in vitro and in vivo studies have suggested that many pathways or factors can stimulate angiogenesis and lymphangiogenesis, which facilitate tumor progression and metastasis. However, the morphological and immunohistochemical profile of newly formed vasculatures has not been elucidated, making it difficult to differentiate them from the pre-existing ones, and to identify their unique molecular profiles for diagnosis and therapeutic interventions.

Experimental findings: As cytokeratin (CK)-19 is a well-recognized stem cell marker and CK-19-positive cells are frequently detected in the peripheral blood of patients with metastatic cancer, our recent studies have assessed the involvement of CK-19 in the formation of new vasculatures in primary colorectal cancer (CRC) tissues. Our studies showed that a subset of lymph node-positive cases harbored some isolated normal epithelial structures with distinct CK-19 immunostaining within an otherwise CK-19-negative background. These structures are exclusively located within or adjacent to lymphoid follicles and are often surrounded by tube-like structures expressing lymphatic endothelial marker D2-40. Similar structures are more frequently seen at the junctions between pre-invasive and invasive CRC with the following features: (1). they consist of a single layer of endothelial cells that express both D2-40 and CD34, (2). their endothelial walls are often incomplete with disseminated cells protruding into the adjacent stroma, and (3). they are exclusively associated with disseminated CK-19-positive cells

Hypothesis: Based on these findings, we propose that these tube-like structures represent newly formed vasculatures, which are derived by the convergence of aberrant lymphocyte infiltration and tumor stem cells. Because of their close physical proximity, tumor stem cells within the epithelial and stromal components contribute equally and coordinately to the morphogenesis of new vasculatures, which constitutes the basis for the unique morphologic and immunohistochemical features of newly formed vasculatures. Our hypothesis appears to be applicable to all epithelium-derived cancers.

Blockade of the renin-angiotensin system improves the early stages of liver regeneration and liver function

BACKGROUND

Partial hepatectomy is the preferred option for selected patients with colorectal cancer liver metastases (CRCLM). Sufficient liver regeneration (LR) is essential for a successful outcome in these patients. The blockade of the renin-angiotensin system (RAS) reduces the growth of several tumor types. The RAS also acts as a regulator of liver fibrosis and potentially LR. The angiotensin-converting enzyme (ACE) inhibitor, captopril, significantly inhibits the growth of CRCLM, but its effect on LR remains undefined.

METHODS

After 70% of partial hepatectomy, mice were randomly assigned to control or captopril-treated groups. LR was measured by liver-to-body weight ratio on days 1, 2, 4, 6, and 8. Hepatocyte proliferation, apoptosis and cell size, hepatic stellate cell (HSC) count, and sinusoidal endothelial cell density were quantified. Matrix metalloproteinase 9 (MMP-9) protein levels, liver injury markers, and RAS messenger RNA levels were also determined.

RESULTS

At day 2, captopril increased liver-to-body weight ratio (56.5 ± 1.7 captopril versus 49.3 ± 2.4 control, P = 0.027). This was associated with increased HSC count (65.4 ± 4.8 cells per 100,000 μm(2), 48.7 ± 2.3, P = 0.007) and MMP-9 levels (0.68 ± 0.12 AU, 0.12 ± 0.04, P = 0.014). The messenger RNA levels of angiotensin-converting enzyme (P = 0.045) and angiotensin 1 receptor (P = 0.039) were reduced by captopril at day 2.

CONCLUSION

Captopril enhanced early LR. This effect was associated with increased HSC numbers and MMP-9 protein, whereas hepatocyte proliferation was lower than controls. Captopril may provide a beneficial treatment option for the management of patients with CRCLM.

The application of pharmacoeconomic modelling to estimate a value-based price for new cancer drugs

RATIONALE, AIMS AND OBJECTIVES

Value-based pricing has recently been discussed by international bodies as a means to estimate a drug price that is linked to the benefits it offers patients and society. The World Health Organization (WHO) has recommended using three times a country's per capita gross domestic product (GDP) as the threshold for economic value. Using the WHO criteria, pharmacoeconomic modelling was used to illustrate the application of value-based price towards bevacizumab, a relatively new drug that provides a 1.4-month survival benefit to patients with metastatic colorectal cancer (mCRC).

METHODS

A decision model was developed to simulate outcomes in mCRC patients receiving chemotherapy ± bevacizumab. Clinical data were obtained from randomized trials and costs from Canadian cancer centres. Utility estimates were determined by interviewing 24 oncology nurses and pharmacists. A price per dose of bevacizumab was then estimated using a target threshold of $CAD117,000 per quality adjusted life year gained, which is three times the Canadian per capita GDP.

RESULTS

For a 1.4-month survival benefit, a price of $CAD830 per dose would be considered cost-effective from the Canadian public health care perspective. If the drug were able to improve patient quality of life or survival from 1.4 to 3 months, the drug price could increase to $CAD1560 and $CAD2180 and still be considered cost-effective.

DISCUSSION

The use of the WHO criteria for estimating a value-based price is feasible, but a balance between what patients/governments can afford to pay and the commercial viability of the product in the reference country would be required.

Prevention of colorectal cancer liver metastasis by exploiting liver immunity via chitosan-TPP/nanoparticles formulated with IL-12

The development of effective therapies for the prevention of colorectal cancer (CRC) liver metastasis is of great importance. Recently, chitosan (CS) nanoparticles have been utilized as carriers of interluekin-12 (IL-12) administered locally to deliver therapeutic proteins and genes. In this study, we encapsulated IL-12 by incorporation using tripolyphosphate (TPP) as the coacervated crosslinking agent to form CS-TPP/IL-12 nanoparticles. We further characterized the association efficiency, rate of release, liver-targeting, and toxicity, which were predominantly dependent on the factors of particle size, zeta potential, pH of solution, and whether or not modified with TPP. Systemic delivery of CS-TPP/IL-12 nanoparticles significantly reduced the number and volume of CRC liver metastasis foci compared to the CS-TPP treated mouse group. Although delivery of IL-12 alone also inhibited the number of CRC liver metastasis observed, further study of the change in hepatic metastasis volume demonstrated no significant differences between the groups treated with CS-TPP or IL-12 alone. Mechanistically, CS-TPP nanoparticles blocked the toxicity of IL-12 and induced infiltration of NK cells and some T cells, which are most likely the effector cells that mediate tumor metastasis inhibition during CS-TPP/IL-12 immunotherapy. The results obtained from this study demonstrate the potential benefit of using chitosan modification technology as a cytokine delivery system for the successful prevention of CRC liver metastasis by exploiting liver immunity.

Thermal ablation

Image-guided tumor ablation refers to a group of treatment modalities that have emerged during the past 2 decades as important tools in the treatment of a wide range of tumors throughout the body. Although most widely recognized in the treatment of hepatic and renal malignancies, the role of thermal ablation has expanded to include lesions of the lung, breast, prostate, bone, as well as other organs and its clinical applications continue to increase. In the following article, we discuss the major thermal ablation modalities, their respective strengths and weaknesses, potential complications and how to avoid them, as well as possible future applications.

Assessment and monitoring tumor vascularity with contrast-enhanced ultrasound maximum intensity persistence imaging

OBJECTIVES

Contrast-enhanced ultrasound imaging is increasingly being used in the clinic for assessment of tissue vascularity. The purpose of our study was to evaluate the effect of different contrast administration parameters on the in vivo ultrasound imaging signal in tumor-bearing mice using a maximum intensity persistence (MIP) algorithm and to evaluate the reliability of in vivo MIP imaging in assessing tumor vascularity. The potential of in vivo MIP imaging for monitoring tumor vascularity during antiangiogenic cancer treatment was further evaluated.

MATERIALS AND METHODS

In intraindividual experiments, varying contrast microbubble concentrations (5 × 10⁵, 5 × 10⁶, 5 × 10⁷, 5 × 10⁸ microbubbles in 100 μL saline) and contrast injection rates (0.6, 1.2, and 2.4 mL/min) in subcutaneous tumor-bearing mice were applied and their effects on in vivo contrast-enhanced ultrasound MIP imaging plateau values were obtained using a dedicated small animal ultrasound imaging system (40 MHz). Reliability of MIP ultrasound imaging was tested following 2 injections of the same microbubble concentration (5 × 10⁷ microbubbles at 1.2 mL/min) in the same tumors. In mice with subcutaneous human colon cancer xenografts, longitudinal contrast-enhanced ultrasound MIP imaging plateau values (baseline and at 48 hours) were compared between mice with and without antiangiogenic treatment (antivascular endothelial growth factor antibody). Ex vivo CD31 immunostaining of tumor tissue was used to correlate in vivo MIP imaging plateau values with microvessel density analysis.

RESULTS

In vivo MIP imaging plateau values correlated significantly (P = 0.001) with contrast microbubble doses. At 3 different injection rates of 0.6, 1.2, and 2.4 mL/min, MIP imaging plateau values did not change significantly (P = 0.61). Following 2 injections with the same microbubble dose and injection rate, MIP imaging plateau values were obtained with high reliability with an intraclass correlation coefficient of 0.82 (95% confidence interval: 0.64, 0.94). In addition, in vivo MIP imaging plateau values significantly correlated (P = 0.01; R² = 0.77) with ex vivo microvessel density analysis. Tumor volumes in treated and nontreated mice did not change significantly (P = 0.22) within 48 hours. In contrast, the change of in vivo MIP imaging plateau values from baseline to 48 hours was significantly different (P = 0.01) in treated versus nontreated mice.

CONCLUSIONS

Contrast-enhanced ultrasound MIP imaging allows reliable assessment of tumor vascularity and monitoring of antiangiogenic cancer therapy in vivo, provided that a constant microbubble dose is administered.

Pharmacodynamic and pharmacogenetic angiogenesis-related markers of first-line FOLFOXIRI plus bevacizumab schedule in metastatic colorectal cancer

Background:

The identification of molecular and genetic markers to predict or monitor the efficacy of bevacizumab (BV) represents a key issue in the treatment of metastatic colorectal cancer (mCRC).

Methods:

Plasma levels of vascular endothelial growth factor (VEGF), placental growth factor (PlGF), soluble VEGF receptor 2 (sVEGFR-2) and thrombospondin-1 (TSP-1) were assessed by ELISA assay at different time points in a cohort of 25 patients enroled in a phase II trial of GONO-FOLFOXIRI plus BV as first-line treatment of mCRC. VEGF: −2578A/C, −1498C/T, −1154A/G, −634C/G and 936C/T; and VEGFR-2: −604A/G, +1192C/T and +1719A/T, polymorphisms were assessed in a total of 54 patients.

Results:

Treatment with GONO-FOLFOXIRI plus BV determined a prolonged and significant reduction in plasma free, biologically active VEGF concentration. Interestingly, VEGF concentrations remained lower than at baseline also at the time of PD. Conversely, PlGF levels increased during the treatment if compared with baseline, suggesting a possible role in tumour resistance; moreover, sVEGFR-2 increased at the time of PD, as well as TSP-1. No association of assessed polymorphisms with outcome was found.

Conclusion:

Our study suggested the possible mechanisms of resistance to combined therapy in those patients with a progressive disease to be tested in ongoing phase III randomised studies.

A pharmacoeconomic modeling approach to estimate a value-based price for new oncology drugs in Europe

Background. Several European governments have recently mandated price cuts in drugs to reduce health care spending. However, such measures without supportive evidence may compromise patient care because manufacturers may withdraw current products or not launch new agents. A value-based pricing scheme may be a better approach for determining a fair drug price and may be a medium for negotiations between the key stakeholders. To demonstrate this approach, pharmacoeconomic (PE) modeling was used from the Spanish health care system perspective to estimate a value-based price for bevacizumab, a drug that provides a 1.4-month survival benefit to patients with metastatic colorectal cancer (mCRC). The threshold used for economic value was three times the Spanish per capita GDP, as recommended by the World Health Organization (WHO).

Methods. A PE model was developed to simulate outcomes in mCRC patients receiving chemotherapy ± bevacizumab. Clinical data were obtained from randomized trials and costs from a Spanish hospital. Utility estimates were determined by interviewing 24 Spanish oncology nurses and pharmacists. A price per dose of bevacizumab was then estimated using a target threshold of €78,300 per quality-adjusted life year gained, which is three times the Spanish per capita GDP.

Results. For a 1.4-month survival benefit, a price of €342 per dose would be considered cost effective from the Spanish public health care perspective. The price may be increased to €733 or €843 per dose if the drug were able to improve patient quality of life or enhance survival from 1.4 to 3 months.

Conclusions. This study demonstrated that a value-based pricing approach using PE modeling and the WHO criteria for economic value is feasible and perhaps a better alternative to government mandated price cuts. The former approach would be a good starting point for opening dialog between European government payers and the pharmaceutical industry.

Hematologic and oncologic diseases and the liver

Malignant and nonmalignant disorders may affect the liver, causing signs and symptoms ranging from mild increases of liver tests to fulminant hepatic failure. This article discusses the most common hematologic and oncologic disorders and their effect on the liver. The section on nonmalignant hematologic disorders includes the anemias, paroxysmal nocturnal hemoglobinuria, disseminated intravascular coagulation, malaria, Banti syndrome, the porphyrias, thrombotic thrombocytopenic purpura, and hemolytic uremic syndrome. Malignant hematologic conditions include leukemias, lymphomas, and myeloproliferative disorders. Other conditions causing portal hypertension and hepatic metastases are also discussed. The most commonly encountered hepatic manifestations of hematologic and oncologic disorders are reviewed.