Self-seeding in cancer

Effect of subsequent bladder cancer on survival in upper tract urothelial carcinoma patients post-radical nephroureterectomy: a systematic review and meta-analysis

BACKGROUND

Radical nephroureterectomy (RNU) is the primary treatment strategy for upper tract urothelial carcinoma (UTUC). However, the intravesical recurrence occurs in 20-50% of all patients. The specific effect of subsequent bladder cancer (SBCa) on survival remains unclear. Therefore, we investigated the effect of SBCa following RNU in patients with UTUC.

METHODS

PubMed, EMBASE, and Cochrane Library were exhaustively searched for studies comparing oncological outcomes between SBCa and without SBCa. Standard cumulative analyses using hazard ratios (HR) with 95% confidence intervals (CI) were performed using Review Manager (version 5.3).

RESULTS

Five studies involving 2057 patients were selected according to the predefined eligibility criteria. Meta-analysis of cancer-specific survival (CSS) and overall survival (OS) revealed no significant differences between the SBCa and non-SBCa groups. However, subgroup analysis of pT0-3N0M0 patients suggested that people with SBCa had worse CSS (HR = 5.13, 95%CI 2.39-10.98, p < 0.0001) and OS (HR = 4.00, 95%CI 2.19-7.31, p < 0.00001).

CONCLUSIONS

SBCa appears to be associated with worse OS in patients with early stage UTUC. However, caution must be taken before recommendations are made because this interpretation is based on very few clinical studies and a small sample size. Research sharing more detailed surgical site descriptions, as well as enhanced outcome data collection and improved reporting, is required to further investigate these nuances.

Exploring the Role of the Gut and Intratumoral Microbiomes in Tumor Progression and Metastasis

Cancer cell dissemination involves invasion, migration, resistance to stressors in the circulation, extravasation, colonization, and other functions responsible for macroscopic metastases. By enhancing invasiveness, motility, and intravasation, the epithelial-to-mesenchymal transition (EMT) process promotes the generation of circulating tumor cells and their collective migration. Preclinical and clinical studies have documented intensive crosstalk between the gut microbiome, host organism, and immune system. According to the findings, polymorphic microbes might play diverse roles in tumorigenesis, cancer progression, and therapy response. Microbial imbalances and changes in the levels of bacterial metabolites and toxins promote cancer progression via EMT and angiogenesis. In contrast, a favorable microbial composition, together with microbiota-derived metabolites, such as short-chain fatty acids (SCFAs), can attenuate the processes of tumor initiation, disease progression, and the formation of distant metastases. In this review, we highlight the role of the intratumoral and gut microbiomes in cancer cell invasion, migration, and metastatic ability and outline the potential options for microbiota modulation. As shown in murine models, probiotics inhibited tumor development, reduced tumor volume, and suppressed angiogenesis and metastasis. Moreover, modulation of an unfavorable microbiome might improve efficacy and reduce treatment-related toxicities, bringing clinical benefit to patients with metastatic cancer.

Evaluation of premetastatic changes in lymph nodes(pN0) of oral tongue tumour: A prospective observational Study

Background: Tongue tumors show intra and inter-tumoral heterogenicity with high incidence, relapse and mortality rates necessitating further research.  Recurrence/metastasis that occurs  after surgical resection of primary cancer is often the reason for poor survival in these patients.  Lymph nodes are the most common site of metastasis in tongue tumors. Therefore, premetastatic molecular changes can be best evaluated in lymph nodes which may epitomize the earliest events in the metastasis cascades. The presence of circulating tumor cells(CTCs) in the absence of nodal disease (N0) may represent tumor aggressiveness, suggesting an immune escape which may have high metastatic potential. This trial  was developed  to investigate the earliest pre-metastatic changes which may regulate tumor dormancy and predict metastasis. A better understanding of organotropism or pre-metastatic changes can help in theragnostic, thereby  preventing the outbreak of overt metastasis.  Methods: A single-institutional prospective observational cohort study. This trial will be conducted at a tertiary care Centre (Amrita Institute of Medical Sciences Kochi).  Eligible patients will be enrolled after obtaining informed consent. The dissected lymph nodes will  be subjected to histopathological and immunohistochemical analyses for premetastatic niche (PMN) formation. In addition, circulating tumor cells will be evaluated before treatment and 6 months after treatment. The patients will be followed  up for a period of two years to correlate the findings with the recurrence-free survival. Expected results:  The pre-metastatic changes, if detected will  be  a predictive biomarker. It may help to define future drug targets for metastasis chemoprevention   . CTCs may  define the tumor aggressiveness ,there by  prognostication  and helps in better disease management. Ethics and dissemination: The study has received the following approval: Ethics Committee of Amrita School of Medicine (ECASM-AIMS-2022-048).Trial Registered Prospectively( CTRI/2022/03/041256 ) on 22/03/2022 under Clinical Trial Registry of India.

Bone serves as a transfer station for secondary dissemination of breast cancer

Metastasis is responsible for the majority of deaths among breast cancer patients. Although parallel polyclonal seeding has been shown to contribute to organ-specific metastasis, in the past decade, horizontal cross-metastatic seeding (metastasis-to-metastasis spreading) has also been demonstrated as a pattern of distant metastasis to multiple sites. Bone, as the most frequent first destination of breast cancer metastasis, has been demonstrated to facilitate the secondary dissemination of breast cancer cells. In this review, we summarize the clinical and experimental evidence that bone is a transfer station for the secondary dissemination of breast cancer. We also discuss the regulatory mechanisms of the bone microenvironment in secondary seeding of breast cancer, focusing on stemness regulation, quiescence-proliferation equilibrium regulation, epigenetic reprogramming and immune escape of cancer cells. Furthermore, we highlight future research perspectives and strategies for preventing secondary dissemination from bone.

Multiple local recurrences of primary sternal chondrosarcoma: tumor manipulation or self-seeding

BACKGROUND

Primary sternal chondrosarcoma, although rare, is the most common malignant tumor of the sternum. The gold standard treatment is complete surgical excision, which frequently causes the instability of the thorax necessitating future reconstruction. Local recurrence is common increasing the risk of distant metastasis.

CASE PRESENTATION

A 60-year-old male patient was diagnosed with primary sternum chondrosarcoma and underwent surgical excision with negative resection margins. Later, he was found to have two local recurrences at 11 months and 37 months post initial excision. The two recurrences were surgically removed followed by local adjuvant radiation.

CONCLUSION

The seeding theories have been reported more frequently with relation to diagnostic biopsy procedures, tumor manipulation and self-seeding tumors. The patient developed two local recurrences despite total resection with negative margins, without concerns regarding seeding in distant metastasis.

Breast cancer: emerging principles of metastasis, adjuvant and neoadjuvant treatment from cancer registry data

PURPOSE

Growing primary breast cancers (PT) can initiate local recurrences (LR), regional lymph nodes (pLN) and distant metastases (MET). Components of these progressions are initiation, frequency, growth duration, and survival. These characteristics describe principles which proposed molecular concepts and hypotheses must align with.

METHODS

In a population-based retrospective modeling approach using data from the Munich Cancer Registry key steps and factors associated with metastasis were identified and quantified. Analysis of 66.800 patient datasets over four time periods since 1978, reliable evidence is obtained even in small subgroups. Together with results of clinical trials on prevention and adjuvant treatment (AT) principles for the MET process and AT are derived.

RESULTS

The median growth periods for PT/MET/LR/pLN comes to 12.5/8.8/5/3.5 years, respectively. Even if 30% of METs only appear after 10 years, a pre-diagnosis MET initiation principle not a delayed one should be true. The growth times of PTs and METs vary by a factor of 10 or more but their ratio is robust at about 1.4. Principles of AT are 50% PT eradication, the selective and partial eradication of bone and lung METs. This cannot be improved by extending the duration of the previously known ATs.

CONCLUSION

A paradigm of ten principles for the MET process and ATs is derived from real world data and clinical trials indicates that there is no rationale for the long-term application of endocrine ATs, risk of PTs by hormone replacement therapies, or cascading initiation of METs. The principles show limits and opportunities for innovation also through alternative interpretations of well-known studies. The outlined MET process should be generalizable to all solid tumors.

Interim analysis of companion, prospective, phase II, clinical trials assessing the efficacy and safety of multi-modal total eradication therapy in men with synchronous oligometastatic prostate cancer

Multimodal therapies were combined to eradicate the primary site, metastatic, and micrometastatic disease in men with newly diagnosed, synchronous, oligometastatic prostate cancer. The investigation included companion, phase II studies: total eradication therapy-1 (TET-1) for those treatment-naïve and total eradication therapy-2 (TET-2) for those post-prostatectomy. The treatment-naive protocol included androgen deprivation and docetaxel (with concurrent abiraterone added in a protocol amendment), followed by a prostatectomy, adjuvant radiation (if positive margins, T3/4, or detectable PSA), and metastasis-directed therapy. The post-prostatectomy protocol assigned the same therapies (omitting the prostatectomy). The primary endpoint was an undetectable PSA with recovered testosterone. The safety boundaries were ≤ 50% for grade 3/4 neutropenic and ≤ 20% for grade 3/4 surgical- and radiation-related toxicities. Enrollment was planned for 60 patients per protocol, to detect a PSA progression-free survival ≥ 32%, as compared to 15% in a historic control. Enrollment closed early. An interim analysis was conducted once > 50% of patients were evaluable for the primary endpoint. The primary endpoint duration was assessed by median progression-free survival. 52 patients were enrolled (n = 26 per protocol). Medium follow-up was 30.3 months. 80% (24/30) of evaluable patients achieved the primary endpoint; the duration was not reached. Of those not evaluable, 77% (17/22) had not reached the endpoint and 23% (5/22) had exited. There were 8% (4/52) grade 3/4 neutropenic and 2% (1/48) grade 3/4 surgical or radiation-induced toxicities. Interim findings suggest the trials' endpoints were met, advancing the concept of total eradication therapy in men with oligometastatic prostate cancer.

Molecular pathology underlying the robustness of cancer stem cells

Intratumoral heterogeneity is tightly associated with the failure of anticancer treatment modalities including conventional chemotherapy, radiation therapy, and molecularly targeted therapy. Such heterogeneity is generated in an evolutionary manner not only as a result of genetic alterations but also by the presence of cancer stem cells (CSCs). CSCs are proposed to exist at the top of a tumor cell hierarchy and are undifferentiated tumor cells that manifest enhanced tumorigenic and metastatic potential, self-renewal capacity, and therapeutic resistance. Properties that contribute to the robustness of CSCs include the abilities to withstand redox stress, to rapidly repair damaged DNA, to adapt to a hyperinflammatory or hyponutritious tumor microenvironment, and to expel anticancer drugs by the action of ATP-binding cassette transporters as well as plasticity with regard to the transition between dormant CSC and transit-amplifying progenitor cell phenotypes. In addition, CSCs manifest the phenomenon of metabolic reprogramming, which is essential for maintenance of their self-renewal potential and their ability to adapt to changes in the tumor microenvironment. Elucidation of the molecular underpinnings of these biological features of CSCs is key to the development of novel anticancer therapies. In this review, we highlight the pathological relevance of CSCs in terms of their hallmarks and identification, the properties of their niche—both in primary tumors and at potential sites of metastasis—and their resistance to oxidative stress dependent on system xc (−).

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Intratumoral heterogeneity driven by CSCs is responsible for therapeutic resistance.

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CTCs survive in the distant organs and achieve colonization, causing metastasis.

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E/M hybrid cancer cells due to partial EMT exhibit the highest metastatic potential.

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The CSC niche regulates stemness in metastatic disease as well as in primary tumor.

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Activation of system xc(-) by CD44 variant in CSCs is a promising therapeutic target.

Single-cell lineages reveal the rates, routes, and drivers of metastasis in cancer xenografts

Detailed phylogenies of tumor populations can recount the history and chronology of critical events during cancer progression, such as metastatic dissemination. We applied a Cas9-based, single-cell lineage tracer to study the rates, routes, and drivers of metastasis in a lung cancer xenograft mouse model. We report deeply resolved phylogenies for tens of thousands of cancer cells traced over months of growth and dissemination. This revealed stark heterogeneity in metastatic capacity, arising from preexisting and heritable differences in gene expression. We demonstrate that these identified genes can drive invasiveness and uncovered an unanticipated suppressive role for KRT17 We also show that metastases disseminated via multidirectional tissue routes and complex seeding topologies. Overall, we demonstrate the power of tracing cancer progression at subclonal resolution and vast scale.

A facile in vitro platform to study cancer cell dormancy under hypoxic microenvironments using CoCl2

BACKGROUND

While hypoxia has been well-studied in various tumor microenvironments, its role in cancer cell dormancy is poorly understood, in part due to a lack of well-established in vitro and in vivo models. Hypoxic conditions under conventional hypoxia chambers are relatively unstable and cannot be maintained during characterization outside the chamber since normoxic response is quickly established. To address this challenge, we report a robust in vitro cancer dormancy model under a hypoxia-mimicking microenvironment using cobalt chloride (CoCl2), a hypoxia-mimetic agent, which stabilizes hypoxia inducible factor 1-alpha (HIF1α), a major regulator of hypoxia signaling.

METHODS

We compared cellular responses to CoCl2 and true hypoxia (0.1% O2) in different breast cancer cell lines (MCF-7 and MDA-MB-231) to investigate whether hypoxic regulation of breast cancer dormancy could be mimicked by CoCl2. To this end, expression levels of hypoxia markers HIF1α and GLUT1 and proliferation marker Ki67, cell growth, cell cycle distribution, and protein and gene expression were evaluated under both CoCl2 and true hypoxia. To further validate our platform, the ovarian cancer cell line OVCAR-3 was also tested.

RESULTS

Our results demonstrate that CoCl2 can mimic hypoxic regulation of cancer dormancy in MCF-7 and MDA-MB-231 breast cancer cell lines, recapitulating the differential responses of these cell lines to true hypoxia in 2D and 3D. Moreover, distinct gene expression profiles in MCF-7 and MDA-MB-231 cells under CoCl2 treatment suggest that key cell cycle components are differentially regulated by the same hypoxic stress. In addition, the induction of dormancy in MCF-7 cells under CoCl2 treatment is HIF1α-dependent, as evidenced by the inability of HIF1α-suppressed MCF-7 cells to exhibit dormant behavior upon CoCl2 treatment. Furthermore, CoCl2 also induces and stably maintains dormancy in OVCAR-3 ovarian cancer cells.

CONCLUSIONS

These results demonstrate that this CoCl2-based model could provide a widely applicable in vitro platform for understanding induction of cancer cell dormancy under hypoxic stress.

Dissecting Time- from Tumor-Related Gene Expression Variability in Bilateral Breast Cancer

Metachronous (MBC) and synchronous bilateral breast tumors (SBC) are mostly distinct primaries, whereas paired primaries and their local recurrences (LRC) share a common origin. Intra-pair gene expression variability in MBC, SBC, and LRC derives from time/tumor microenvironment-related and tumor genetic background-related factors and pairs represents an ideal model for trying to dissect tumor-related from microenvironment-related variability. Pairs of tumors derived from women with SBC (n = 18), MBC (n = 11), and LRC (n = 10) undergoing local-regional treatment were profiled for gene expression; similarity between pairs was measured using an intraclass correlation coefficient (ICC) computed for each gene and compared using analysis of variance (ANOVA). When considering biologically unselected genes, the highest correlations were found for primaries and paired LRC, and the lowest for MBC pairs. By instead limiting the analysis to the breast cancer intrinsic genes, correlations between primaries and paired LRC were enhanced, while lower similarities were observed for SBC and MBC. Focusing on stromal-related genes, the ICC values decreased for MBC and were significantly different from SBC. These findings indicate that it is possible to dissect intra-pair gene expression variability into components that are associated with genetic origin or with time and microenvironment by using specific gene subsets.

Breast Cancer Brain Metastases: Clonal Evolution in Clinical Context

Brain metastases are highly-evolved manifestations of breast cancer arising in a unique microenvironment, giving them exceptional adaptability in the face of new extrinsic pressures. The incidence is rising in line with population ageing, and use of newer therapies that stabilise metastatic disease burden with variable efficacy throughout the body. Historically, there has been a widely-held view that brain metastases do not respond to circulating therapeutics because the blood-brain-barrier (BBB) restricts their uptake. However, emerging data are beginning to paint a more complex picture where the brain acts as a sanctuary for dormant, subclinical proliferations that are initially protected by the BBB, but then exposed to dynamic selection pressures as tumours mature and vascular permeability increases. Here, we review key experimental approaches and landmark studies that have charted the genomic landscape of breast cancer brain metastases. These findings are contextualised with the factors impacting on clonal outgrowth in the brain: intrinsic breast tumour cell capabilities required for brain metastatic fitness, and the neural niche, which is initially hostile to invading cells but then engineered into a tumour-support vehicle by the successful minority. We also discuss how late detection, abnormal vascular perfusion and interstitial fluid dynamics underpin the recalcitrant clinical behaviour of brain metastases, and outline active clinical trials in the context of precision management.

First-in-Human Phase 1 Trial of Agarose Beads Containing Murine RENCA Cells in Advanced Solid Tumors

PURPOSE

Agarose macrobeads containing mouse renal adenocarcinoma cells (RMBs) release factors, suppressing the growth of cancer cells and prolonging survival in spontaneous or induced tumor animals, mediated, in part, by increased levels of myocyte-enhancing factor (MEF2D) via EGFR-and AKT-signaling pathways. The primary objective of this study was to determine the safety of RMBs in advanced, treatment-resistant metastatic cancers, and then its efficacy (survival), which is the secondary objective.

METHODS

Thirty-one patients underwent up to four intraperitoneal implantations of RMBs (8 or 16 macrobeads/kg) via laparoscopy in this single-arm trial (FDA BB-IND 10091; NCT 00283075). Serial physical examinations, laboratory testing, and PET-CT imaging were performed before and three months after each implant.

RESULTS

RMBs were well tolerated at both dose levels (mean 660.9 per implant). AEs were (Grade 1/2) with no treatment-related SAEs.

CONCLUSION

The data support the safety of RMB therapy in advanced-malignancy patients, and the preliminary evidence for their potential efficacy is encouraging. A Phase 2 efficacy trial is ongoing.

Liquid biopsy and NSCLC

In the era of high-throughput molecular screening and personalized medicine, difficulty in determining whether cancer mutations are truly 'actionable' remains a gray zone in NSCLC. The most important prerequisite to perform such investigations is the tumor tissue retrieval via biopsy at diagnosis and after occurrence of resistance. Blood-based liquid biopsy as circulating tumor cells, circulating tumor DNA and exosomes can offer a fast and non-invasive method to elucidate the genetic heterogeneity of patients, the screening and patient stratification and give a dynamic surveillance for tumor progression and monitor treatments response. Here we prospectively discuss the three main approaches in the blood-biopsy field of lung cancer patients and its clinical applications in patient management. We also outline some of the analytical challenges that remain for liquid biopsy techniques in demonstrating that it could represent a true and actionable picture in lung cancer management for the implementation into clinical routine.

Minimal residual disease in breast cancer: an overview of circulating and disseminated tumour cells

Within the field of cancer research, focus on the study of minimal residual disease (MRD) in the context of carcinoma has grown exponentially over the past several years. MRD encompasses circulating tumour cells (CTCs)—cancer cells on the move via the circulatory or lymphatic system, disseminated tumour cells (DTCs)—cancer cells which have escaped into a distant site (most studies have focused on bone marrow), and resistant cancer cells surviving therapy—be they local or distant, all of which may ultimately give rise to local relapse or overt metastasis. Initial studies simply recorded the presence and number of CTCs and DTCs; however recent advances are allowing assessment of the relationship between their persistence, patient prognosis and the biological properties of MRD, leading to a better understanding of the metastatic process. Technological developments for the isolation and analysis of circulating and disseminated tumour cells continue to emerge, creating new opportunities to monitor disease progression and perhaps alter disease outcome. This review outlines our knowledge to date on both measurement and categorisation of MRD in the form of CTCs and DTCs with respect to how this relates to cancer outcomes, and the hurdles and future of research into both CTCs and DTCs.

Metastatic Spread Emerging From Liver Metastases of Colorectal Cancer: Does the Seed Leave the Soil Again?

OBJECTIVE

To investigate whether liver metastases contribute to metastatic spread of colorectal cancer (CRC) by shedding intact tumor cells.

BACKGROUND

Metastases represent the primary cause of death in CRC. Understanding the metastatic activity of metastases and which patients are at high risk for tumor cell dissemination may, therefore, have significant influence on cancer care in the future.

METHODS

Circulating tumor cells (CTCs) were detected in the hepatic inflow (portal venous blood [PVB]) and outflow compartment (hepatic venous blood [HVB]) of a training (n = 55) and validation (n = 50) set using the CellSearch system. Isolated CTC from the HVB were subjected to gene expression analyses by quantitative polymerase chain reaction.

RESULTS

CTC detection rate (37.2% vs 19.6%; P = 0.04) and count (mean: 12.7, SEM: ± 5.9 vs 1.9; ± 1.2; P = 0.01) were significantly higher in HVB compared to PVB. The increased CTC detection rate (54% vs 11.4%; P < 0.001) and CTC count (14.7 ± 5.1 vs 1.1 ± 0.6; P < 0.001) in the HVB compared to the PVB compartment was confirmed in the validation cohort. Expression of epithelial markers and genes involved in cell-to-cell and cell-to-matrix adhesion was reduced in CTC compared to tumor cells in liver metastases. Metastasis size greater than 5 cm was associated with CTC shedding from established liver metastases in the training and validation cohorts.

CONCLUSIONS

Colorectal liver metastases shed intact tumor cells with an invasive phenotype. Metastasis size serves as a surrogate marker for metastatic activity of colorectal liver metastases.

The mathematics of cancer: integrating quantitative models

Mathematical modelling approaches have become increasingly abundant in cancer research. The complexity of cancer is well suited to quantitative approaches as it provides challenges and opportunities for new developments. In turn, mathematical modelling contributes to cancer research by helping to elucidate mechanisms and by providing quantitative predictions that can be validated. The recent expansion of quantitative models addresses many questions regarding tumour initiation, progression and metastases as well as intra-tumour heterogeneity, treatment responses and resistance. Mathematical models can complement experimental and clinical studies, but also challenge current paradigms, redefine our understanding of mechanisms driving tumorigenesis and shape future research in cancer biology.

Niche inheritance: a cooperative pathway to enhance cancer cell fitness through ecosystem engineering

Cancer cells can be described as an invasive species that is able to establish itself in a new environment. The concept of niche construction can be utilized to describe the process by which cancer cells terraform their environment, thereby engineering an ecosystem that promotes the genetic fitness of the species. Ecological dispersion theory can then be utilized to describe and model the steps and barriers involved in a successful diaspora as the cancer cells leave the original host organ and migrate to new host organs to successfully establish a new metastatic community. These ecological concepts can be further utilized to define new diagnostic and therapeutic areas for lethal cancers. 115: 1478–1485, 2014. © 2014 Wiley Periodicals, Inc.

Disseminated tumor cells from the bone marrow of patients with nonmetastatic primary breast cancer are predictive of locoregional relapse

BACKGROUND

Disseminated tumor cells (DTCs) are detectable in the bone marrow (BM) of patients with primary breast cancer (PBC) and predictive of an impaired prognosis. This large trial aimed to analyze the impact of DTC detection on locoregional relapse (LR).

PATIENTS AND METHODS

Patients with nonmetastatic PBC were eligible for this analysis. BM aspiration (BMA1) was carried out during primary surgery and DTCs were detected by using immunocytochemistry (A45-B/B3 antibody against pancytokeratin) and morphological criteria. At the time of LR, a subgroup of patients with nonmetastatic and operable LR received a secondary BM aspiration (BMA2).

RESULTS

A total of 3072 patients were included into the analysis. Of these, 732 (24%) presented with DTCs at BMA1. One hundred thirty-nine patients experienced LR and 48 of these (35%) were initially DTC positive. DTC detection was significantly associated with an increased risk of LR in univariate (P = 0.002) and multivariate analysis (P = 0.009) with a hazard ratio of 1.65 (95% confidence interval 1.13-2.40). Of the patients with LR, 55 patients were available for BMA2 and 17 of these (32%) were DTC positive. DTC detection at the time of LR was indicative of impaired overall survival (univariate analysis, P = 0.037).

CONCLUSIONS

DTC detection in patients with PBC is associated with an increased risk of LR, indicating that tumor cells may have the ability to recirculate from the BM to the site of the primary tumor. The impaired prognosis associated with DTC detection at the time of LR may help to identify patients that are in need for additional or more aggressive treatment.

Repurposing the antipsychotic trifluoperazine as an antimetastasis agent

Because cancer cell invasion is a critical determinant of metastasis, targeting invasion is a viable approach to prevent metastasis. Utilizing a novel three-dimensional high-throughput invasion assay, we screened a National Cancer Institute compound library and discovered compounds demonstrating inhibitory effects on cancer cell invasion. One hit, trifluoperazine, suppresses invasion of human cancer cell lines while displaying a limited cytotoxicity profile. This inhibition is due to the interference with cancer cell migratory ability but not proteolytic activity. Treatment of cancer cells with trifluoperazine significantly reduces angiogenesis and prevents cancer cell invasion through a chorioallantoic basement membrane. Mechanistically, treatment results in decreased phosphorylated AKT (Ser(473) and Thr(308)) and β-catenin (Ser(552)). Lack of phosphorylation of Ser(552) of β-catenin prevents β-catenin nuclear relocation, resulting in decreased expression of vascular endothelial growth factor, likely mediated through dopamine receptor D2. Taken together, we demonstrated that trifluoperazine is responsible for reducing the angiogenic and invasive potential of aggressive cancer cells through dopamine receptor D2 to modulate the β-catenin pathway and propose that trifluoperazine may be used as an antimetastasis chemotherapeutic.

Outcomes after stereotactic body radiotherapy for lung tumors, with emphasis on comparison of primary lung cancer and metastatic lung tumors

Background

The goal of this study was to determine the prognostic factors associated with an improved overall outcome after stereotactic body radiotherapy (SBRT) for primary lung cancer and metastatic lung tumors.

Methods

A total of 229 lung tumors in 201 patients were included in the study. SBRT of 45 Gy in 3 fractions, 48 Gy in 4 fractions, 60 Gy in 8 fractions or 60 Gy in 15 fractions was typically used to treat 172 primary lungs cancer in 164 patients and 57 metastatic lung tumors in 37 patients between January 2001 and December 2011. Prognostic factors for local control (LC) and overall survival (OS) were analyzed using a Cox proportional hazards model.

Results

The median biologically effective dose was 105.6 Gy based on alpha/beta = 10 (BED10). The median follow-up period was 41.9 months. The 3-year LC and OS rates were 72.5% and 60.9%, and the 5-year LC and OS rates were 67.8% and 38.1%, respectively. Radiation pneumonitis of grades 2, 3 and 5 occurred in 22 petients, 6 patients and 1 patient, respectively. Multivariate analyses revealed that tumor origin (primary lung cancer or metastatic lung tumor, p < 0.001), tumor diameter (p = 0.005), BED10 (p = 0.029) and date of treatment (p = 0.011) were significant independent predictors for LC and that gender (p = 0.012), tumor origin (p = 0.001) and tumor diameter (p < 0.001) were significant independent predictors for OS.

Conclusions

SBRT resulted in good LC and tolerable treatment-related toxicities. Tumor origin and tumor diameter are significant independent predictors for both overall survival and local control.

The cancer diaspora: Metastasis beyond the seed and soil hypothesis

Do cancer cells escape the confinement of their original habitat in the primary tumor or are they forced out by ecologic changes in their home niche? Describing metastasis in terms of a simple one-way migration of cells from the primary to the target organs is an insufficient concept to cover the nuances of cancer spread. A diaspora is the scattering of people away from an established homeland. To date, "diaspora" has been a uniquely human term used by social scientists; however, the application of the diaspora concept to metastasis may yield new biologic insights as well as therapeutic paradigms. The diaspora paradigm takes into account, and models, several variables including: the quality of the primary tumor microenvironment, the fitness of individual cancer cell migrants as well as migrant populations, the rate of bidirectional migration of cancer and host cells between cancer sites, and the quality of the target microenvironments to establish metastatic sites. Ecologic scientific principles can be applied to the cancer diaspora to develop new therapeutic strategies. For example, ecologic traps - habitats that lead to the extinction of a species - can be developed to attract cancer cells to a place where they can be better exposed to treatments or to cells of the immune system for improved antigen presentation. Merging the social science concept of diaspora with ecologic and population sciences concepts can inform the cancer field to understand the biology of tumorigenesis and metastasis and inspire new ideas for therapy.

Critical research gaps and translational priorities for the successful prevention and treatment of breast cancer

INTRODUCTION

Breast cancer remains a significant scientific, clinical and societal challenge. This gap analysis has reviewed and critically assessed enduring issues and new challenges emerging from recent research, and proposes strategies for translating solutions into practice.

METHODS

More than 100 internationally recognised specialist breast cancer scientists, clinicians and healthcare professionals collaborated to address nine thematic areas: genetics, epigenetics and epidemiology; molecular pathology and cell biology; hormonal influences and endocrine therapy; imaging, detection and screening; current/novel therapies and biomarkers; drug resistance; metastasis, angiogenesis, circulating tumour cells, cancer 'stem' cells; risk and prevention; living with and managing breast cancer and its treatment. The groups developed summary papers through an iterative process which, following further appraisal from experts and patients, were melded into this summary account.

RESULTS

The 10 major gaps identified were: (1) understanding the functions and contextual interactions of genetic and epigenetic changes in normal breast development and during malignant transformation; (2) how to implement sustainable lifestyle changes (diet, exercise and weight) and chemopreventive strategies; (3) the need for tailored screening approaches including clinically actionable tests; (4) enhancing knowledge of molecular drivers behind breast cancer subtypes, progression and metastasis; (5) understanding the molecular mechanisms of tumour heterogeneity, dormancy, de novo or acquired resistance and how to target key nodes in these dynamic processes; (6) developing validated markers for chemosensitivity and radiosensitivity; (7) understanding the optimal duration, sequencing and rational combinations of treatment for improved personalised therapy; (8) validating multimodality imaging biomarkers for minimally invasive diagnosis and monitoring of responses in primary and metastatic disease; (9) developing interventions and support to improve the survivorship experience; (10) a continuing need for clinical material for translational research derived from normal breast, blood, primary, relapsed, metastatic and drug-resistant cancers with expert bioinformatics support to maximise its utility. The proposed infrastructural enablers include enhanced resources to support clinically relevant in vitro and in vivo tumour models; improved access to appropriate, fully annotated clinical samples; extended biomarker discovery, validation and standardisation; and facilitated cross-discipline working.

CONCLUSIONS

With resources to conduct further high-quality targeted research focusing on the gaps identified, increased knowledge translating into improved clinical care should be achievable within five years.

Markers of circulating breast cancer cells

The detection of circulating tumor cells (CTC) aids in diagnosis of disease, prognosis, disease recurrence, and therapeutic response. The molecular aspects of metastasis are reviewed including its relevance in the identification and characterization of putative markers that may be useful in the detection thereof. Also discussed are methods for CTC enrichment using molecular strategies. The clinical application of CTC in the metastatic disease process is also summarized.