Daily low-dose/continuous capecitabine combined with neo-adjuvant irradiation reduces VEGF and PDGF-BB levels in rectal carcinoma patients

Ovarian recurrence risk assessment using machine learning, clinical information, and serum protein levels to predict survival in high grade ovarian cancer

In ovarian cancer, there is no current method to accurately predict recurrence after a complete response to chemotherapy. Here, we develop a machine learning risk score using serum proteomics for the prediction of early recurrence of ovarian cancer after initial treatment. The developed risk score was validated in an independent cohort with serum collected prospectively during the remission period. In the discovery cohort, patients scored as low-risk had a median time to recurrence (TTR) that was not reached at 10 years compared to 10.5 months (HR 4.66, p < 0.001) in high-risk patients. In the validation cohort, low-risk patients had a median TTR which was not reached compared to 4.7 months in high-risk patients (HR 4.67, p = 0.009). In advanced-stage patients with a CA125 < 10, low-risk patients had a median TTR of 68 months compared to 6 months in high-risk patients (HR 2.91, p = 0.02). The developed risk score was capable of distinguishing the duration of remission in ovarian cancer patients. This score may help guide maintenance therapy and develop innovative treatments in patients at risk at high-risk of recurrence.

Chemotherapy-Induced Metastasis: Molecular Mechanisms, Clinical Manifestations, Therapeutic Interventions

Chemotherapy offers long-term clinical benefits to many patients with advanced cancer. However, recent evidence has linked the cytotoxic effects of chemotherapy with the de novo elicitation of a prometastatic tumor microenvironment. This "modified" tumor microenvironment is triggered by a chemotherapy-driven cytokine storm or through direct effects of certain chemotherapeutics on stromal and/or immune cells, the most critical being tumor-associated macrophages. These chemotherapy-educated cells act as facilitators in tumor-host cell interactions promoting the establishment of distant metastasis. Certain clinical studies now offer substantial evidence that prometastatic changes are indeed identified in the tumor microenvironment of certain patient subpopulations, especially those that do not present with any pathologic response after neoadjuvant chemotherapy. Deciphering the exact contextual prerequisites for chemotherapy-driven metastasis will be paramount for designing novel mechanism-based treatments for circumventing chemotherapy-induced metastasis.

Serum levels of VEGF and MCSF in HER2+ / HER2- breast cancer patients with metronomic neoadjuvant chemotherapy

Metronomic therapy has been gaining importance in the neoadjuvant setting of breast cancer treatment. Its clinical benefits may involve antiangiogenic machinery. Cancer cells induce angiogenesis to support tumor growth by secreting factors, such as vascular endothelial growth factor (VEGF). In breast cancer, Trastuzumab (TZM) based treatment is of key importance and is believed to reduce diameter and volume of blood vessels as well as vascular permeability. Here in we investigated serum levels of angiogenic factors VEGF and MCSF in patients receiving metronomic neoadjuvant therapy with or without TZM. We observed in HER2+ cohort stable levels of MCSF through treatment, whereas VEGF trend was of decreasing levels. In HER2- cohort we observed increasing levels of MCSF and VEGF trend. Overall, HER2+ patients had better pathological response to treatment. These findings suggest that angiogenic pathway may be involved in TZM anti-tumoral effect in the neoadjuvant setting.

Does metronomic chemotherapy induce tumor angiogenic dormancy? A review of available preclinical and clinical data

Tumor dormancy is the ability of cancer cells to survive in a non-proliferating state. This condition can depend on three main mechanisms: cell cycle arrest (quiescence or cell dormancy), immunosurveillance (immunologic dormancy), or lack of functional blood vessels (angiogenic dormancy). In particular, under angiogenic dormancy, cancer cell proliferation is counterbalanced by apoptosis owing to poor vascularization, impeding tumor mass expansion beyond a microscopic size, with an asymptomatic and non-metastatic state. Tumor vasculogenic or non-angiogenic switch is essential to promote escape from tumor dormancy, leading to tumor mass proliferation and metastasis. In avascular lesions angiogenesis process results blocked from the equilibrium between pro- and anti-angiogenic factors, such as vascular endothelial growth factor (VEGF) and thrombospondin-1 (TSP-1), respectively. The angiogenic switch mainly depends on the disruption of this balance, in favor of pro-angiogenic factors, and on the recruitment of circulating endothelial progenitors (CEPs) that promote the formation of new blood vessels. Metronomic chemotherapy, the regular intake of doses able to sustain low but active concentrations of chemotherapeutic drugs during protracted time periods, is an encouraging therapeutic approach that has shown to upregulate anti-angiogenic factors such as TSP-1 and decline pro-angiogenic factors such as VEGF, suppressing the proangiogenic cells such as CEPs. In this perspective, metronomic chemotherapy may be one of the available therapeutic approaches capable to modulate favorably the angiogenic tumor dormancy, but further research is essential to better define this particular characteristic.

Integrated Microfluidic Platform with Multiple Functions To Probe Tumor-Endothelial Cell Interaction

Interaction between tumor and endothelial cells could affect tumor growth and progression and induce drug resistance during cancer therapy. Investigation of tumor-endothelial cell interaction involves cell coculture, protein detection, and analysis of drug metabolites, which are complicated and time-consuming. In this work, we present an integrated microfluidic device with three individual components (cell coculture component, protein detection component, and pretreatment component for drug metabolites) to probe the interaction between tumor and endothelial cells. Cocultured cervical carcinoma cells (CaSki cells) and human umbilical vein endothelial cells (HUVECs) show higher resistance to chemotherapeutic agents than single-cultured cells, indicated by higher cell viability, increased expression of angiogenic proteins, and elevated level of paclitaxel metabolites under coculture conditions. This integrated microfluidic platform with multiple functions facilitates understanding of the interaction between tumor and endothelial cells, and it may become a promising tool for drug screening within an engineered tumor microenvironment.

A systematic literature analysis of correlative studies in low-dose metronomic chemotherapy trials

Low-dose metronomic (LDM) chemotherapy is a beneficial and very well-tolerated form of chemotherapy utilization characterized by the frequent and uninterrupted administration of low doses of conventional chemotherapeutic agents over prolonged periods of time. While patients resistant to standard maximum tolerated dose (MTD) chemotherapy may still benefit from LDM chemotherapy, there is a lack of predictive markers of response to LDM chemotherapy. We searched the MEDLINE, EMBASE, CENTRAL and PubMed databases for correlative studies conducted as part of LDM chemotherapy trials in order to identify the most promising biomarker candidates. Given the antiangiogenic properties of LDM chemotherapy, angiogenesis-related biomarkers were most commonly studied. However, significant correlations between angiogenesis-related biomarkers and study end points were rare and variable, even so far as biomarkers correlating positively with an end point in some studies and negatively with the same end point in other studies. Pursuing biomarkers outside the angiogenesis field may be more promising.

Combining bevacizumab and chemoradiation in rectal cancer. Translational results of the AXEBeam trial

Background:

This study characterises molecular effect of bevacizumab, and explores the relation of molecular and genetic markers with response to bevacizumab combined with chemoradiotherapy (CRT).

Methods:

From a subset of 59 patients of 84 rectal cancer patients included in a phase II study combining bevacizumab with CRT, tumour and blood samples were collected before and during treatment, offering the possibility to evaluate changes induced by one dose of bevacizumab. We performed cDNA microarrays, stains for CD31/CD34 combined with α-SMA and CA-IX, as well as enzyme-linked immunosorbent assay (ELISA) for circulating angiogenic proteins. Markers were related with the pathological response of patients.

Results:

One dose of bevacizumab changed the expression of 14 genes and led to a significant decrease in microvessel density and in the proportion of pericyte-covered blood vessels, and a small but nonsignificant increase in hypoxia. Alterations in angiogenic processes after bevacizumab delivery were only detected in responding tumours. Lower PDGFA expression and PDGF-BB levels, less pericyte-covered blood vessels and higher CA-IX expression were found after bevacizumab treatment only in patients with pathological complete response.

Conclusions:

We could not support the ‘normalization hypothesis' and suggest a role for PDGFA, PDGF-BB, CA-IX and α-SMA. Validation in larger patient groups is needed.

[Development of siRNA delivery strategy by active control of tumor microenvironment]

Efficient systemic siRNA delivery to cells in the target tissue is a current critical challenge in the drug delivery field. Several studies have demonstrated that nanoparticles such as polyethylene glycol (PEG)-coated siRNA-lipoplexes may enhance the systemic delivery of siRNA to tumor. However, the disordered tumor microenvironment still poses a potential impediment with respect to the efficient delivery of PEG-coated siRNA-lipoplexes. We recently showed that metronomic S-1 dosing (daily oral administration) enhanced the accumulation of PEG-coated liposome containing anticancer drug in solid tumor tissue and thereby increased therapeutic efficacy in tumor-bearing mouse model. To extend this work, we tried to investigate the effect of metronomic S-1 dosing on the intratumoral accumulation of PEG-coated siRNA-lipoplex and, thereby, their therapeutic efficacy in solid tumor-bearing mouse model. Results showed that metronomic S-1 dosing improved systemic delivery of intravenously injected PEG-coated siRNA-lipoplexes into solid tumor tissue. In addition, the combined therapy of S-1 and PEG-coated siRNA-lipoplexes showed potent tumor growth suppressive effect. Our proposed strategy may pose a promising therapeutic one to conquer cancer progression with siRNA.

Serial measurements of serum PDGF-AA, PDGF-BB, FGF2, and VEGF in multiresistant ovarian cancer patients treated with bevacizumab

INTRODUCTION

Anti-VEGF treatment has proven effective in recurrent ovarian cancer. However, the identification of the patients most likely to respond is still pending. It is well known that the angiogenesis is regulated by several other pro-angiogenic proteins, e.g. the platelet - derived growth factor (PDGF) system and the fibroblast growth factor (FGF) system. These other signaling pathways may remain active or become upregulated during anti-VEGF treatment.The aim of the present study was to investigate if potential changes of PDGF-BB, PDGF-AA, and FGF2 before and during bevacizumab treatment had predictive value for early progression or survival. Furthermore, we wanted to investigate the importance of serum VEGF in the same cohort.

METHODS

This study included 106 patients with chemotherapy-resistant epithelial ovarian cancer who were treated with single agent bevacizumab as part of a biomarker protocol. Patients were evaluated for response by the Response Evaluation Criteria In Solid Tumors (RECIST) and/ or Gynecologic Cancer Intergroup (GCIG) CA125 criteria. Serum samples were collected at baseline and prior to each treatment. FGF2, PDGF-BB, PDGF-AA were quantified simultaneously using the Luminex system, and VEGF-A was measured by ELISA. Eighty-eight baseline samples were avaliable for FGF2, PDGF-BB, PDGF-AA analysis, and 93 baseline samples for VEGF.

RESULTS

High baseline serum VEGF was related to poor overall survival. Furthermore, high serum PDGF-BB and FGF2 was of prognostic significance. None of the markers showed predictive value, neither at baseline level nor during the treatment.

Aptamer-nanoparticle assembly for logic-based detection

In this work, gold nanoparticles perform Boolean logic operations in response to two proangiogenic targets important in cancer diagnosis and treatment: PDGF and VEGF. In the absence of protein target, gold nanoparticles are initially dispersed as a red solution; the addition of target proteins causes nanoparticle aggregation, turning the solution blue, as well as the release of dye-labeled aptamer probes, which causes an increase in fluorescence. These outputs constitute an AND or OR gate for simultaneous protein detection. We believe this logic-gate-based detection system will become the basis for novel rapid, cheap, and reliable sensors for diagnostic applications.