A randomized phase II study of cediranib alone versus cediranib in combination with dasatinib in docetaxel resistant, castration resistant prostate cancer patients

Development and validation of a survival nomogram and calculator for male patients with metastatic castration-resistant prostate cancer treated with abiraterone acetate and/or enzalutamide

BACKGROUND

Despite the widespread availability of medication choices for metastatic castration-resistant prostate cancer (mCRPC), biomarkers to predict the efficacy of each mCRPC treatment have not yet been established. This study developed a prognostic nomogram and a calculator to predict the prognosis of patients with mCRPC who received abiraterone acetate (ABI) and/or enzalutamide (ENZ).

METHODS

In total, 568 patients with mCRPC who underwent ABI and/or ENZ between 2012 and 2017 were enrolled. A prognostic nomogram based on the risk factors was developed using the Cox proportional hazards regression model and clinically important factors. The discriminatory ability of the nomogram was assessed according to the concordance index (C-index). A 5-fold cross-validation was repeated 2000 times to estimate the C-index, and the means of the estimated C-index for the training and validation sets were determined. A calculator based on this nomogram was then developed.

RESULTS

The median overall survival (OS) was 24.7 months. Multivariate analysis showed that the time to CRPC, pre-chemotherapy, baseline prostate-specific antigen, baseline alkaline phosphatase, and baseline lactate dehydrogenase levels were independent risk factors for OS (hazard ratio [HR]: 0.521, 1.681, 1.439, 1.827, and 12.123, p = 0.001, 0.001,  < 0.001, 0.019, and  < 0.001, respectively). The C-index was 0.72 in the training cohort and 0.71 in the validation cohort.

CONCLUSIONS

We developed a nomogram and calculator to predict OS in Japanese patients with mCRPC who received ABI and/or ENZ. Reproducible prognostic prediction calculators for mCRPC will facilitate greater accessibility for clinical use.

Renal adverse reactions of tyrosine kinase inhibitors in the treatment of tumours: A Bayesian network meta-analysis

Objectives: Tumours remain a serious threat to human life. Following rapid progress in oncology research, tyrosine kinase inhibitors have been used to treat multiple tumour types. Given the great influence of kidneys on pharmacokinetics, renal toxicities associated with TKIs have attracted attention. However, the TKIs with the lowest risks of renal impairment are unclear. In this study, we conducted a Bayesian network meta-analysis to compare the incidence of renal impairment among different TKIs in patients with tumours. Methods and analysis: Six databases (PubMed, EMBASE, The Cochrane Library, Chinese National Knowledge Infrastructure, Wanfang Data, and China Biomedical Literature Database) were electronically searched from inception to 1 November 2021 to identify randomized controlled trials on the incidence of renal impairment for different TKIs in patients with tumours. Two reviewers independently screened the literature, extracted data, and assessed the risk of bias of the included studies. Then, a pairwise meta-analysis was conducted using Stata version 13, and network meta-analysis within the Bayesian framework was conducted using R software version 3.5.3 with the package "gemtc 0.8-2" recalling JAGS (version 4.3.0). Results: Overall, 34 randomized controlled trials were included in this study. Although renal toxicity was common among patients receiving TKIs, the incidence and severity greatly differed among the drugs and studies. Elevated creatinine and protein levels were the most common nephrotoxic events, whereas haematuria was relatively rare. Among TKIs, nintedanib and ripretinib carried the lowest risks of renal impairment. Conclusion: TKIs displayed different profiles of renal toxicity because of their different targets and underlying mechanisms. Clinicians should be aware of the risks of renal impairment to select the optimal treatment and improve patient adherence to treatment. Systematic Review Registration: [www.crd.york.ac.uk/prospero/], identifier [CRD42022295853].

The Androgen Receptor and Its Crosstalk With the Src Kinase During Castrate-Resistant Prostate Cancer Progression

While the androgen receptor (AR) signalling is the mainstay therapeutic target for metastatic prostate cancers, these tumours will inevitably develop therapy resistance to AR pathway inhibitors suggesting that prostate tumour cells possess the capability to develop mechanisms to bypass their dependency on androgens and/or AR to survive and progress. In many studies, protein kinases such as Src are reported to promote prostate tumour progression. Specifically, the pro-oncogene tyrosine Src kinase regulates prostate cancer cell proliferation, adhesion, invasion, and metastasis. Not only can Src be activated under androgen depletion, low androgen, and supraphysiological androgen conditions, but also through crosstalk with other oncogenic pathways. Reciprocal activations between Src and AR proteins had also been reported. These findings rationalize Src inhibitors to be used to treat castrate-resistant prostate tumours. Although several Src inhibitors had advanced to clinical trials, the failure to observe patient benefits from these studies suggests that further evaluation of the roles of Src in prostate tumours is required. Here, we summarize the interplay between Src and AR signalling during castrate-resistant prostate cancer progression to provide insights on possible approaches to treat prostate cancer patients.

Repurposing therapeutics for malignant pleural mesothelioma (MPM) - Updates on clinical translations and future outlook

INTRODUCTION

Malignant pleural mesothelioma (MPM) is a rare malignancy affecting the mesothelial cells in the pleural lining surrounding the lungs. First approved chemotherapy against MPM was a platinum/antifolate (cisplatin/pemetrexed) (2003). Since then, no USFDA approvals have gone through for small molecules as these molecules have not been proven to be therapeutically able in later stages of clinical studies. An alternative to conventional chemotherapy can be utilization of monoclonal antibodies, which are proven to improve patient survival significantly as compared to conventional chemotherapy (Nivolumab + Ipilimumab, 2020).

AREA COVERED

Drug repurposing has been instrumental in drug discovery for rare diseases such as MPM and multiple repositioned small molecule therapies and immunotherapies are currently being tested for its applicability in MPM management. This article summarizes essential breakthroughs along the pre-clinical and clinical developmental stages of small molecules and monoclonal antibodies for MPM management.

EXPERT OPINION

For rare diseases such as malignant pleural mesothelioma, a drug repurposing strategy can be adapted as it eases the financial burden on pharmaceutical companies along with fast-tracking development. With the rise of multiple small molecule repurposed therapies and innovations in localized treatment, MPM therapeutics are bound to be more effective in this decade.

Matrix stiffening and acquired resistance to chemotherapy: concepts and clinical significance

Extracellular matrix (ECM) refers to the non-cellular components of the tumour microenvironment, fundamentally providing a supportive scaffold for cellular anchorage and transducing signaling cues that orchestrate cellular behaviour and function. The ECM integrity is abrogated in several cases of cancer, ending in aberrant activation of a number of mechanotransduction pathways and induction of multiple tumorigenic events such as extended proliferation, cell death resistance, epithelial-mesenchymal transition and most importantly the development of chemoresistance. In this regard, the present study mainly aims to elucidate how the ECM-stiffening process may contribute to the development of chemoresistance during cancer progression and what pharmacological approaches are required for tackling this issue. Hence, the first section of this review explains the process of ECM stiffening and the ways it may affect biochemical pathways to induce chemoresistance in a clinic. In addition, the second part focuses on describing some of the most important pharmacological agents capable of targeting ECM components and underlying pathways for overcoming ECM-induced chemoresistance. Finally, the third part discusses the obtained results from the application of these agents in the clinic for overcoming chemoresistance.

Patterns of indolence in prostate cancer (Review)

Although prostate cancer is a major cause of cancer-related mortality worldwide, most patients will have a relatively indolent clinical course. Contrary to most other types of cancer, even the diagnosis of locally advanced or metastatic disease is not always lethal. The present review aimed to summarize what is known regarding the underlying mechanisms related to the indolent course of subsets of prostate cancer, at various stages. The data suggested that no specific gene alteration by itself was responsible for carcinogenesis or disease aggressiveness. However, pathway analysis identified genetic aberrations in multiple critical pathways that tend to accumulate over the course of the disease. The progression from indolence into aggressive disease is associated with a complex interplay in which genetic and epigenetic factors are involved. The effect of the immune tumor microenvironment is also very important. Emerging evidence has suggested that the upregulation of pathways related to cellular aging and senescence can identify patients with indolent disease. In addition, a number of tumors enter a long-lasting quiescent state. Further research will determine whether halting tumor evolution is a feasible option, and whether the life of patients can be markedly prolonged by inducing tumor senescence or long-term dormancy.

KIF15 Promotes Progression of Castration Resistant Prostate Cancer by Activating EGFR Signaling Pathway

Castration-resistant prostate cancer (CRPC) continues to be a major clinical problem and its underlying mechanisms are still not fully understood. The epidermal growth factor receptor (EGFR) activation is an important event that regulates mitogenic signaling. EGFR signaling plays an important role in the transition from androgen dependence to castration-resistant state in prostate cancer (PCa). Kinesin family member 15 (KIF15) has been suggested to be overexpressed in multiple malignancies. Here, we demonstrate that KIF15 expression is elevated in CRPC. We show that KIF15 contributes to CRPC progression by enhancing the EGFR signaling pathway, which includes complex network intermediates such as mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K)/AKT pathways. In CRPC tumors, increased expression of KIF15 is positively correlated with EGFR protein level. KIF15 binds to EGFR, and prevents EGFR proteins from degradation in a Cdc42-dependent manner. These findings highlight the key role of KIF15 in the development of CRPC and rationalize KIF15 as a potential therapeutic target.

Protein kinase inhibitors for the treatment of prostate cancer

INTRODUCTION

Protein kinases have emerged as targetable pathways used in metastatic prostate cancer given their role in prostatic tumor growth, proliferation and metastases. Protein kinase inhibitors are small molecules that target varying pathways including the breakpoint cluster region (BCR)-Abelson tyrosine kinase (ABL), colony stimulating factor-1 receptor (CSF1R), vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR) and phosphoinositide 3-kinase (PI3K) pathways and have been studied in prostate cancer trials with variable results. In particular, cabozantinib when used in combination trials and ipatasertib, when used with abiraterone in patients who harbor phosphatase and tensin homologue (PTEN) loss, have been promising.

AREAS COVERED

This article reviews the key early and late phase clinical trials currently investigating the use of protein kinase inhibitors in prostate cancer.

EXPERT OPINION

While multiple kinase inhibitors show promising results in prostate cancer, none have yet garnered Food and Drug Administration (FDA) approval. Studies are ongoing with the best candidate drugs discussed herein. However, multiple drugs have failed primary endpoints in prostate cancer. Therefore, further understanding of the potential mechanisms of resistance, combination and trial design of combination therapy may help pave the way for targeting kinase inhibition in prostate cancer.

Osteoblasts derived from mouse mandible enhance tumor growth of prostate cancer more than osteoblasts derived from long bone

Prostate cancer (PCa) metastasizes to bone, where the bone marrow microenvironment controls disease progression. However, the cellular interactions that result in active bone marrow metastases are poorly understood. A better understanding of these interactions is critical to success in the pursuit of effective treatments for this life ending disease. Anecdotally, we observe that after intracardiac injection of PCa cells, one of the greatest tools to investigate the mechanisms of bone-metastatic disease, animals frequently present with mandible metastasis before hind limb metastasis. Therefore, in this study, we investigated whether the bone cells derived from the mouse mandible influence PCa progression differently than those from the hind limb. Interestingly, we found that osteoblasts harvested from mouse mandibles grew faster, expressed more vascular endothelial growth factor (VEGF), increased vascularity and formed more bone, and stimulated faster growth of PCa cells when cultured together than osteoblasts harvested from mouse hind limbs. Additionally, these findings were confirmed in vivo when mouse mandible osteoblasts were co-implanted into mice with PCa cells. Importantly, the enhancement of PCa growth mediated by mandible osteoblasts was not shown to be due to their differentiation or proliferation activities, but may be partly due to increased vascularization and expression of VEGF.

A Phase 2 Trial of Abiraterone Followed by Randomization to Addition of Dasatinib or Sunitinib in Men With Metastatic Castration-Resistant Prostate Cancer

BACKGROUND

Resistance to novel androgen signaling inhibition and metastatic castration-resistant prostate cancer (mCRPC) progression is likely dependent on tumor microenvironment interactions. The Src pathway and neoangiogenesis have been implicated in prostate cancer progression. We studied the effect of adding the targeted agents dasatinib and sunitinib to abiraterone acetate (AA) in men with mCRPC.

PATIENTS AND METHODS

In this open-label randomized phase 2 study, mCRPC patients received AA. At resistance to AA, they were randomized 1:1 to combination with dasatinib or sunitinib. At second progression, patients crossed over. The primary end point was time to treatment failure (TTF), defined as time to progression or death. Secondary end points included overall survival and safety.

RESULTS

From March 2011 to February 2015, a total of 179 patients were enrolled and 132 subsequently randomized. Median TTF was 5.7 months in the dasatinib group and 5.5 months in the sunitinib group. There was no difference between the two groups in terms of TTF (hazard ratio, 0.85; 95% confidence interval, 0.59-1.22). Median overall survival from study entry was 26.3 months in the dasatinib group and 27.7 months in the sunitinib group (hazard ratio, 1.02; 95% confidence interval, 0.71-1.47). Grade 3 or higher adverse events related to study medication were more frequent with sunitinib (n = 44, 46%) compared to dasatinib (n = 26, 24%). At data cutoff, 7 patients were experiencing a continuous response to AA, with a median duration of treatment of 5.7 years.

CONCLUSION

There is no difference in overall survival and TTF between dasatinib and sunitinib combined with abiraterone in the treatment of patients with bone mCRPC.

Multikinase inhibitor-induced liver injury in patients with cancer: A review for clinicians

BACKGROUND

Multikinase inhibitors (MKI) are targeted molecular agents that have revolutionized cancer management. However, there is a paucity of data concerning MKI-related liver injury risk and clinical guidelines for the management of liver toxicity in patients receiving MKI for cancer are scarce.

DESIGN

We conducted a PubMed search of articles in English published from January 2000 to December 2018 related to hepatotoxicity of the 29 FDA-approved MKIs at doses used in clinical practice. The search terms were the international non-proprietary name of each agent cross-referenced with «hepatotoxicity», «hepatitis», «hepatic adverse event», or «liver failure», and «phase II clinical trial», «phase III clinical trial», or «case report».

RESULTS

Following this search, 140 relevant studies and 99 case reports were considered. Although asymptomatic elevation of aminotransferase levels has been frequently observed in MKI clinical trials, clinically significant hepatotoxicity is a rare event. In most cases, the interval between treatment initiation and the onset of liver injury is between one week and two months. Liver toxicity is often hepatocellular and less frequently mixed. Life-threatening MKI-induced hepatic injury has been described, involving fulminant liver failure or death. Starting from existing data, a description of MKI-related liver events, grading of hepatotoxicity risk, and recommendations for management are also given for various MKI molecules.

CONCLUSION

All MKIs can potentially cause liver injury, which is sometimes irreversible. As there is still no strategy available to prevent MKI-related hepatotoxicity, early detection remains crucial. The surveillance of liver function during treatment may help in the early detection of hepatotoxicity. Furthermore, the exclusion of potential causes of hepatic injury is essential to avoid unnecessary MKI withdrawal.

A high neutrophil-to-lymphocyte ratio is a poor prognostic factor for castration-resistant prostate cancer patients who undergo abiraterone acetate or enzalutamide treatment

BACKGROUND

Inflammatory cytokine markers, including the neutrophil-to-lymphocyte ratio (NLR), monocyte-lymphocyte ratio, and platelet-to-lymphocyte ratio, play important roles as prognostic markers in several solid malignancies, including prostate cancer. We previously reported the NLR as a poor prognostic marker in bladder cancer, upper-urothelial carcinoma, adrenocortical carcinoma, penile cancer, and prostate cancer. This study examined the importance of the NLR as a prognostic marker for castration-resistant prostate cancer (CRPC) patients who received abiraterone acetate or enzalutamide.

METHODS

A total of 805 prostate cancer patients developed in CRPC status were enrolled in this study. Of these patients, 449 received abiraterone acetate (ABI; 188 cases) or enzalutamide (ENZ; 261 cases) treatment, and the pre-treatment NLR values of these patients were obtained. We investigated the prognosis in those with higher and lower NLR values.

RESULTS

The median NLR was 2.90, and a receiver operating characteristics analysis suggested a candidate cut-off point of 3.02. The median overall survival (OS) was 17.3 months in the higher NLR group (≥3.02) and 27.3 months in the lower NLR group (< 3.02) (p < 0.0001). This trend was also observed in both the ABI and ENZ groups (ABI: 29.3 vs. 15.1 months; ENZ: NR vs. 19.5 months; p < 0.0001 and < 0.0001, respectively). A multivariate analysis revealed that a higher NLR was an independent risk factor. The NLR value was thus shown to be correlated with the prostate cancer progression.

CONCLUSIONS

A higher NLR was associated with a poorer OS for CRPC patients who received ABI or ENZ. The NLR was positively correlated with prostate cancer progression.

Investigational luteinizing hormone releasing hormone (LHRH) agonists and other hormonal agents in early stage clinical trials for prostate cancer

INTRODUCTION

The treatment and management of prostate cancer continues to evolve; newer classes of agents and combination therapies are being developed and some are being investigated in early phase clinical trials.

AREAS COVERED

We discuss investigational hormonal agents for the treatment of prostate cancer and focus primarily on luteinizing hormone releasing hormone (LHRH) agonists in early stage trials. We look at agents that target the hormonal axis, including anti-androgens, gonadotropins, estrogenic agents and progestogenic agents and other non-hormonal agents often used in combination with LHRH agonists. We review these candidates in the specific clinical niche in which they might find utility.

EXPERT OPINION

Of all candidate compounds being evaluated in clinical trials, very few will receive FDA approval. Few, if any of the investigational agents discussed here will be used routinely in clinical practice for treating prostate cancer. Recognizing the reasons for the failure of agents to advance to later stage trials is important. Furthermore, a thorough understanding of the mechanisms underlying prostate cancer pathogenesis, including various points in the HGPA and parallel pathways, will help identify potentially actionable targets.

A first-in-human phase I study to determine the maximum tolerated dose of the oral Src/ABL inhibitor AZD0424

BACKGROUND

Src is involved in cancer invasion and metastasis. AZD0424, an oral inhibitor of Src and ABL1, has shown evidence of anti-tumour activity in pre-clinical studies.

METHODS

A phase Ia, dose escalation study was performed to assess the safety of continuous oral dosing with AZD0424 in advanced solid tumours. Secondary objectives included investigation of AZD0424 pharmacokinetics, effect on Src activity using markers of bone turnover, and anti-tumour activity.

RESULTS

41 patients were treated; 34 received AZD0424 once-daily at doses ranging from 5 mg to 150 mg, and 7 received 40 mg bi-daily 41.5% of patients experienced at least one AZD0424-related adverse event that was Grade 3-5 in severity, with patients treated at doses above 60 mg per day experiencing multiple treatment-related toxicities. The most commonly observed AZD0424-related adverse events were nausea, fatigue, anorexia and alopecia. Cmax and AUC increased linearly with dose and the mean±standard deviation t1/2 was 8.4±2.8 h. Clear evidence of Src target inhibition was seen at doses ⩾20 mg per day. No responses were observed and 7 patients (17.1%) achieved stable disease lasting 6 weeks or more.

CONCLUSIONS

AZD0424 displayed no evidence of efficacy as monotherapy despite a clear pharmacodynamic effect. Further evaluation of AZD0424 monotherapy in patients with solid tumours is not recommended.

A novel canine histiocytic sarcoma cell line: initial characterization and utilization for drug screening studies

Background

Histiocytic sarcoma is a rare disorder in humans, however it is seen with appreciable frequency in certain breeds of dogs, such as Bernese mountain dog. The purpose of this study was to fully characterize a novel canine histiocytic sarcoma cell line, and utilize it as a tool to screen for potential therapeutic drugs.

Methods

The histiocytic sarcoma cell line was characterized by expression of cellular markers as determined by immunohistochemistry and flow cytometry techniques. The neoplastic cells were also evaluated for their capability of phagocytizing beads particles, and their potential to grow as xenograft in an immunodeficient mouse. We investigated the in vitro cytotoxic activity of a panel of thirteen compounds using the MTS proliferation assay. Inhibitory effects of different drugs were compared using one-way ANOVA, and multiple means were compared using Tukey’s test.

Results

Neoplastic cells expressed CD11c, CD14, CD18, CD45, CD172a, CD204, MHC I, and vimentin. Expression of MHC II was upregulated after exposure to LPS. Furthermore, the established cell line clearly demonstrated phagocytic activity similar to positive controls of macrophage cell line. The xenograft mouse developed a palpable subcutaneous soft tissue mass after 29 days of inoculation, which histologically resembled the primary neoplasm. Dasatinib, a tyrosine kinase pan-inhibitor, significantly inhibited the growth of the cells in vitro within a clinically achievable and tolerable plasma concentration. The inhibitory response to dasatinib was augmented when combined with doxorubicin.

Conclusions

In the present study we demonstrated that a novel canine histiocytic sarcoma cell line presents a valuable tool to evaluate novel treatment approaches. The neoplastic cell line favorably responded to dasatinib, which represents a promising anticancer strategy for the treatment of this malignancy in dogs and similar disorders in humans.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4132-0) contains supplementary material, which is available to authorized users.

Primary versus castration-resistant prostate cancer: modeling through novel murine prostate cancer cell lines

Cell lines representing the progression of prostate cancer (PC) from an androgen-dependent to an androgen-independent state are scarce. In this study, we used previously characterized prostate luminal epithelial cell line (Plum), under androgen influence, to establish cellular models of PC progression. Cells derived from orthotopic tumors have been isolated to develop an androgen-dependent (PLum-AD) versus an androgen-independent (PLum-AI) model. Upon immunofluorescent, qRT-PCR and Western blot analyses, PLum-AD cells mostly expressed prostate epithelial markers while PLum-AI cells expressed mesenchymal cell markers. Interestingly, both cell lines maintained a population of stem/progenitor cells. Furthermore, our data suggest that both cell lines are tumorigenic; PLum-AD resulted in an adenocarcinoma whereas PLum-AI resulted in a sarcomatoid carcinoma when transplanted subcutaneously in NOD-SCID mice. Finally, gene expression profiles showed enrichment in functions involved in cell migration, apoptosis, as well as neoplasm invasiveness and metastasis in PLum-AI cells. In conclusion, these data suggest that the newly isolated cell lines represent a new in vitro model of androgen-dependent and –independent PC.

Strategies to avoid treatment-induced lineage crisis in advanced prostate cancer

The increasing potency of therapies that target the androgen receptor (AR) signalling axis has correlated with a rise in the proportion of patients with prostate cancer harbouring an adaptive phenotype, termed treatment-induced lineage crisis. This phenotype is characterized by features that include soft-tissue metastasis and/or resistance to standard anticancer therapies. Potent anticancer treatments might force cancer cells to evolve and develop alternative cell lineages that are resistant to primary therapies, a mechanism similar to the generation of multidrug- resistant microorganisms after continued antibiotic use. Herein, we assess the hypothesis that treatment-adapted phenotypes harbour reduced AR expression and/or activity, and acquire compensatory strategies for cell survival. We highlight the striking similarities between castration-resistant prostate cancer and triple-negative breast cancer, another poorly differentiated endocrine malignancy. Alternative treatment paradigms are needed to avoid therapy-induced resistance. Herein, we present a new clinical trial strategy designed to evaluate the potential of rapid drug cycling as an approach to delay the onset of resistance and treatment-induced lineage crisis in patients with metastatic castration-resistant prostate cancer.

Identification of target genes of cediranib in alveolar soft part sarcoma using a gene microarray

The aim of the present study was to identify the target genes of cediranib and the associated signaling pathways in alveolar soft part sarcoma (ASPS). A microarray dataset (GSE32569) was obtained from the Gene Expression Omnibus database. The R software package was used for data normalization and screening of differentially expressed genes (DEGs). The Database for Annotation, Visualization and Integrated Discovery was used to perform Gene Ontology analysis. Gene Set Enrichment Analysis was performed to obtain the up- and downregulated pathways in ASPS. The Distant Regulatory Elements of co-regulated genes database was used to identify the transcription factors (TFs) that were enriched in the signaling pathways. A protein-protein interaction (PPI) network was constructed using the Search Tool for the Retrieval of Interacting Genes/Proteins database and was visualized using Cytoscape software. A total of 71 DEGs, including 59 upregulated genes and 12 downregulated genes, were identified. Gene sets associated with ASPS were enriched primarily in four signaling pathways: The phenylalanine metabolism pathway, the mitogen-activated protein kinase (MAPK) signaling pathway, the taste transduction pathway and the intestinal immune network for the production of immunoglobulin A. Furthermore, 107 TFs were identified to be enriched in the MAPK signaling pathway. Certain genes, including those coding for Fms-like tyrosine kinase 1, kinase insert domain receptor, E-selectin and platelet-derived growth factor receptor D, that were associated with other genes in the PPI network, were identified. The present study identified certain potential target genes and the associated signaling pathways of cediranib action in ASPS, which may be helpful in understanding the efficacy of cediranib and the development of new targets for cediranib.

Src promotes castration-recurrent prostate cancer through androgen receptor-dependent canonical and non-canonical transcriptional signatures

Progression of prostate cancer (PC) to castration-recurrent growth (CRPC) remains dependent on sustained expression and transcriptional activity of the androgen receptor (AR). A major mechanism contributing to CRPC progression is through the direct phosphorylation and activation of AR by Src-family (SFK) and ACK1 tyrosine kinases. However, the AR-dependent transcriptional networks activated by Src during CRPC progression have not been elucidated. Here, we show that activated Src (Src527F) induces androgen-independent growth in human LNCaP cells, concomitant with its ability to induce proliferation/survival genes normally induced by dihydrotestosterone (DHT) in androgen-dependent LNCaP and VCaP cells. Src induces additional gene signatures unique to CRPC cell lines, LNCaP-C4-2 and CWR22Rv1, and to CRPC LuCaP35.1 xenografts. By comparing the Src-induced AR-cistrome and/or transcriptome in LNCaP to those in CRPC and LuCaP35.1 tumors, we identified an 11-gene Src-regulated CRPC signature consisting of AR-dependent, AR binding site (ARBS)-associated genes whose expression is altered by DHT in LNCaP[Src527F] but not in LNCaP cells. The differential expression of a subset (DPP4, BCAT1, CNTNAP4, CDH3) correlates with earlier PC metastasis onset and poorer survival, with the expression of BCAT1 required for Src-induced androgen-independent proliferation. Lastly, Src enhances AR binding to non-canonical ARBS enriched for FOXO1, TOP2B and ZNF217 binding motifs; cooperative AR/TOP2B binding to a non-canonical ARBS was both Src- and DHT-sensitive and correlated with increased levels of Src-induced phosphotyrosyl-TOP2B. These data suggest that CRPC progression is facilitated via Src-induced sensitization of AR to intracrine androgen levels, resulting in the engagement of canonical and non-canonical ARBS-dependent gene signatures.

Rapid optimization of drug combinations for the optimal angiostatic treatment of cancer

Drug combinations can improve angiostatic cancer treatment efficacy and enable the reduction of side effects and drug resistance. Combining drugs is non-trivial due to the high number of possibilities. We applied a feedback system control (FSC) technique with a population-based stochastic search algorithm to navigate through the large parametric space of nine angiostatic drugs at four concentrations to identify optimal low-dose drug combinations. This implied an iterative approach of in vitro testing of endothelial cell viability and algorithm-based analysis. The optimal synergistic drug combination, containing erlotinib, BEZ-235 and RAPTA-C, was reached in a small number of iterations. Final drug combinations showed enhanced endothelial cell specificity and synergistically inhibited proliferation (p < 0.001), but not migration of endothelial cells, and forced enhanced numbers of endothelial cells to undergo apoptosis (p < 0.01). Successful translation of this drug combination was achieved in two preclinical in vivo tumor models. Tumor growth was inhibited synergistically and significantly (p < 0.05 and p < 0.01, respectively) using reduced drug doses as compared to optimal single-drug concentrations. At the applied conditions, single-drug monotherapies had no or negligible activity in these models. We suggest that FSC can be used for rapid identification of effective, reduced dose, multi-drug combinations for the treatment of cancer and other diseases.

SRC: marker or actor in prostate cancer aggressiveness

A key question for urologic practitioners is whether an apparently organ-confined prostate cancer (PCa) is actually aggressive or not. The dilemma is to specifically identify among all prostate tumors the very aggressive high-grade cancers that will become life-threatening by developing extra-prostatic invasion and metastatic potential and the indolent cancers that will never modify a patient's life expectancy. A choice must be made between several therapeutic options to achieve the optimal personalized management of the disease that causes as little harm as possible to patients. Reliable clinical, biological, or pathological markers that would enable distinctions to be made between aggressive and indolent PCas in routine practice at the time of initial diagnosis are still lacking. The molecular mechanisms that explain why a PCa is aggressive or not are also poorly understood. Among the potential markers and/or actors in PCa aggressiveness, Src and other members of the Src kinase family, are valuable candidates. Activation of Src-dependent intracellular pathways is frequently observed in PCa. Indeed, Src is at the cross-roads of several pathways [including androgen receptor (AR), TGFbeta, Bcl-2, Akt/PTEN or MAPK, and ERK …], and is now known to influence some of the cellular and tissular events that accompany tumor progression: cell proliferation, cell motility, invasion, epithelial-to-mesenchymal transition, resistance to apoptosis, angiogenesis, neuroendocrine differentiation, and metastatic spread. Recent work even suggests that Src could also play a part in PCa initiation in coordination with the AR. The aim of this review is to gather data that explore the links between the Src kinase family and PCa progression and aggressiveness.