Expression profiling of G2/M phase regulatory proteins in normal, premalignant and malignant uterine cervix and their correlation with survival of patients

Development of MPS1 Inhibitors: Recent Advances and Perspectives

Monopolar spindle kinase 1 (MPS1) plays a pivotal role as a dual-specificity kinase governing spindle assembly checkpoint activation and sister chromatid separation in mitosis. Its overexpression has been observed in various human malignancies. MPS1 reduces spindle assembly checkpoint sensitivity, allowing tumor cells with a high degree of aneuploidy to complete mitosis and survive. Thus, MPS1 has emerged as a promising candidate for cancer therapy. Despite the identification of numerous MPS1 inhibitors, only five have advanced to clinical trials with none securing FDA approval for cancer treatment. In this perspective, we provide a concise overview of the structural and functional characteristics of MPS1 by highlighting its relevance to cancer. Additionally, we explore the structure-activity relationships, selectivity, and pharmacokinetics of MPS1 inhibitors featuring diverse scaffolds. Moreover, we review the reported work on enhancing MPS1 inhibitor selectivity, offering valuable insights into the discovery of novel, highly potent small-molecule MPS1 inhibitors.

PDZ and LIM Domain-Encoding Genes: Their Role in Cancer Development

PDZ-LIM family proteins (PDLIMs) are a kind of scaffolding proteins that contain PDZ and LIM interaction domains. As protein-protein interacting molecules, PDZ and LIM domains function as scaffolds to bind to a variety of proteins. The PDLIMs are composed of evolutionarily conserved proteins found throughout different species. They can participate in cell signal transduction by mediating the interaction of signal molecules. They are involved in many important physiological processes, such as cell differentiation, proliferation, migration, and the maintenance of cellular structural integrity. Studies have shown that dysregulation of the PDLIMs leads to tumor formation and development. In this paper, we review and integrate the current knowledge on PDLIMs. The structure and function of the PDZ and LIM structural domains and the role of the PDLIMs in tumor development are described.

Molecular Markers to Predict Prognosis and Treatment Response in Uterine Cervical Cancer

Uterine cervical cancer is one of the leading causes of cancer-related mortality in women worldwide. Each year, over half a million new cases are estimated, resulting in more than 300,000 deaths. While less-invasive, fertility-preserving surgical procedures can be offered to women in early stages, treatment for locally advanced disease may include radical hysterectomy, primary chemoradiotherapy (CRT) or a combination of these modalities. Concurrent platinum-based chemoradiotherapy regimens remain the first-line treatments for locally advanced cervical cancer. Despite achievements such as the introduction of angiogenesis inhibitors, and more recently immunotherapies, the overall survival of women with persistent, recurrent or metastatic disease has not been extended significantly in the last decades. Furthermore, a broad spectrum of molecular markers to predict therapy response and survival and to identify patients with high- and low-risk constellations is missing. Implementation of these markers, however, may help to further improve treatment and to develop new targeted therapies. This review aims to provide comprehensive insights into the complex mechanisms of cervical cancer pathogenesis within the context of molecular markers for predicting treatment response and prognosis.

FOXD3‑AS1/miR‑128‑3p/LIMK1 axis regulates cervical cancer progression

Long non‑coding RNA forkhead box D3 antisense RNA 1 (FOXD3‑AS1) functions as an oncogenic regulator in several types of cancer, including breast cancer, glioma and cervical cancer. However, the effects and mechanisms underlying FOXD3‑AS1 in cervical cancer (CC) are not completely understood. The present study aimed to investigate the biological functions and potential molecular mechanisms underlying FOXD3‑AS1 in CC progression. Reverse transcription‑quantitative PCR was performed to detect FOXD3‑AS1, microRNA (miR)‑128‑3p and LIM domain kinase 1 (LIMK1) expression levels in CC tissues and cells. Immunohistochemical staining and western blotting were conducted to assess LIMK1 protein expression levels in CC tissues and cells, respectively. Cell Counting Kit‑8 and BrdU assays were used to determine the role of FOXD3‑AS1 in regulating cell proliferation. CC cell migration and invasion were assessed by performing Transwell assays. Dual‑luciferase reporter assays were conducted to verify the binding between miR‑128‑3p and FOXD3‑AS1. FOXD3‑AS1 expression was significantly increased in CC tissues and cell lines compared with adjacent healthy tissues and normal cervical epithelial cells, respectively. High FOXD3‑AS1 expression was significantly associated with poor differentiation of tumor tissues, increased tumor size and positive lymph node metastasis. FOXD3‑AS1 overexpression significantly increased CC cell proliferation, migration and invasion compared with the negative control (NC) group, whereas FOXD3‑AS1 knockdown resulted in the opposite effects compared with the small interfering RNA‑NC group. Moreover, the results demonstrated that FOXD3‑AS1 targeted and negatively regulated miR‑128‑3p, which indirectly upregulated LIMK1 expression. Therefore, the present study demonstrated that FOXD3‑AS1 upregulated LIMK1 expression via competitively sponging miR‑128‑3p in CC cells, promoting CC progression.

Polo like kinase 1 expression in cervical cancer tissues generated from multiple detection methods

Background

Existing studies of PLK1 in cervical cancer had several flaws. The methods adopted by those studies of detecting PLK1 expression in cervical cancer were single and there lacks comprehensive evaluation of the clinico-pathological significance of PLK1 in cervical cancer.

Methods

A total of 303 cervical tissue samples were collected for in-house tissue microarrays. Immunohistochemistry was performed for evaluating PLK1 expression between cervical cancer (including cervical squamous cell carcinoma (CESC) and cervical adenocarcinoma) and non-cancer samples. The Expression Atlas database was searched for querying PLK1 expression in different cervical cancer cell lines and different tissues in the context of pan-cancer. Standard mean difference (SMD) was calculated and the summarized receiver's operating characteristics (SROC) curves were plotted for integrated tissue microarrays, exterior high-throughput microarrays and RNA sequencing data as further verification. The effect of PLK1 expression on the overall survival, disease-free survival and event-free survival of cervical cancer patients was analyzed through Kaplan Meier survival curves for cervical cancer patients from RNA-seq and GSE44001 datasets. The gene mutation and alteration status of PLK1 in cervical cancer was inspected in COSMIC and cBioPortal databases. Functional enrichment analysis was performed for genes correlated with PLK1 from aggregated RNA-seq and microarrays.

Results

A total of 963 cervical cancer samples and 178 non-cancer samples were collected from in-house tissue microarrays and exterior microarrays and RNA-seq datasets. The combined expression analysis supported overexpression of PLK1 in CESC, cervical adenocarcinoma and all types of cervical cancer (SMD = 1.59, 95%CI [0.56-2.63]; SMD = 2.99, 95%CI [0.75-5.24]; SMD = 1.57, 95% CI [0.85-2.29]) and the significant power of PLK1 expression in distinguishing CESC or all types of cervical cancer samples from non-cancer samples (AUC = 0.94, AUC = 0.92). Kaplan-Meier survival curves showed that the event-free survival rate of cervical cancer patients with higher expression of PLK1 was shorter than that of patients with lower PLK1 (HR = 2.020, P = 0.0197). Genetic alteration of PLK1 including missense mutation and mRNA low occurred in 6% of cervical cancer samples profiled in mRNA expression. Genes positively or negatively correlated with PLK1 were mainly assembled in pathways such as DNA replication, cell cycle, mismatch repair, Ras signaling pathway, melanoma, EGFR tyrosine kinase inhibitor resistance and homologous recombination (P < 0.05).

Conclusions

Here, we provided sufficient evidence of PLK1 overexpression in cervical cancer. The overexpression of PLK1 in cervical cancer and the contributory effect of it on clinical progression indicated the hopeful prospect of PLK1 as a biomarker for cervical cancer.

LncRNA CRNDE acts as an oncogene in cervical cancer through sponging miR-183 to regulate CCNB1 expression

Studies have identified a series of lncRNAs that contributed to various tumors, although the underlying mechanisms remain largely unclear. We proposed a ceRNA network and investigate relations among lncRNA/miRNA/mRNA in cervical cancer (CC). The genes of differential expression and lncRNA/miRNA/mRNA network were identified by combining TCGA, miRcode, starBase, miRTarBase, miRDB, TargetScan and STRING databases. Meanwhile, the function enrichment was recognized with Gene Ontology and Kyoto Encyclopedia of Genes and Genomes. Quantitative real time-PCR (qRT-PCR) was performed to determine colorectal neoplasia differentially expressed (CRNDE) expression in CC tissues and cell lines. The effects of CRNDE on the CC biological functions and cyclin B1 (CCNB1) expression were detected by conducting in vitro and in vivo experiments. Quantitative real time-PCR, western blot and dual-luciferase reporter assay were used to predict the target of miR-183. Furthermore, rescue experiments were conducted to further confirm the regulation of CCNB1 by CRNDE. Systematic analyses of bioinformatics from several databases predicted that CRNDE, miR-183 and CCNB1 were in the same network path. Their expressions were up-regulated in CC tissues and cells. Silencing CRNDE-inhibited cell proliferation, migration and invasion, restricted solid tumor growth and promoted cell apoptosis. Moreover, our results suggested that miR-183 targeted the CCNB1 3'UTR and regulated its expression. Additionally, miR-183 mimic could inverse the antitumor function of CRNDE inhibition and partially eliminated the attenuated expression of CCNB1 induced by silencing CRNDE, indicating that CRNDE could positively regulate CCNB1 expression by sponging miR-183. Our study highlighted a role for the CRNDE/miR-183/CCNB1-axis in CC and offered a promising diagnostic strategy for CC treatment.

Integrating Multiple Data Sources for Combinatorial Marker Discovery: A Study in Tumorigenesis

Identification of combinatorial markers from multiple data sources is a challenging task in bioinformatics. Here, we propose a novel computational framework for identifying significant combinatorial markers ( s) using both gene expression and methylation data. The gene expression and methylation data are integrated into a single continuous data as well as a (post-discretized) boolean data based on their intrinsic (i.e., inverse) relationship. A novel combined score of methylation and expression data (viz., ) is introduced which is computed on the integrated continuous data for identifying initial non-redundant set of genes. Thereafter, (maximal) frequent closed homogeneous genesets are identified using a well-known biclustering algorithm applied on the integrated boolean data of the determined non-redundant set of genes. A novel sample-based weighted support ( ) is then proposed that is consecutively calculated on the integrated boolean data of the determined non-redundant set of genes in order to identify the non-redundant significant genesets. The top few resulting genesets are identified as potential s. Since our proposed method generates a smaller number of significant non-redundant genesets than those by other popular methods, the method is much faster than the others. Application of the proposed technique on an expression and a methylation data for Uterine tumor or Prostate Carcinoma produces a set of significant combination of markers. We expect that such a combination of markers will produce lower false positives than individual markers.

MUC16 contributes to the metastasis of pancreatic ductal adenocarcinoma through focal adhesion mediated signaling mechanism. Genes Cancer. 2016;7:110-124. [PMID: 27382435 PMCID: PMC4918949 DOI: 10.18632/genesandcancer.104]

MUC16, a heavily glycosylated type-I transmembrane mucin is overexpressed in several cancers including pancreatic ductal adenocarcinoma (PDAC). Previously, we have shown that MUC16 is significantly overexpressed in human PDAC tissues. However, the functional consequences and its role in PDAC is poorly understood. Here, we show that MUC16 knockdown decreases PDAC cell proliferation, colony formation and migration in vitro. Also, MUC16 knockdown decreases the tumor formation and metastasis in orthotopic xenograft mouse model. Mechanistically, immunoprecipitation and immunofluorescence analyses confirms MUC16 interaction with galectin-3 and mesothelin in PDAC cells. Adhesion assay displayed decreased cell attachment of MUC16 knockdown cells with recombinant galectin-1 and galectin-3 protein. Further, CRISPR/Cas9-mediated MUC16 knockout cells show decreased tumor-associated carbohydrate antigens (T and Tn) in PDAC cells. Importantly, carbohydrate antigens were decreased in the region that corresponds to MUC16 and suggests for the decreased MUC16-galectin interactions. Co-immunoprecipitation also revealed a novel interaction between MUC16 and FAK in PDAC cells. Interestingly, we observed decreased expression of mesenchymal and increased expression of epithelial markers in MUC16-silenced cells. Additionally, MUC16 loss showed a decreased FAK-mediated Akt and ERK/MAPK activation. Altogether, these findings suggest that MUC16-focal adhesion signaling may play a critical role in facilitating PDAC growth and metastasis.

Application of flow cytometry for evaluating clinical prognosis and histopathological grade of human glioma

OBJECTIVES

Flow cytometry was applied to predict the biological parameters of tumor behavior based on the DNA content distribution of tumors. We used flow cytometry to determine the number of cell cycles for the characterization of intracranial gliomas and its possible prognostic role.

METHODS

Flow cytometric analysis of the DNA content was performed for 37 fresh operative glioma specimens. The expression of Ki-67 in glioma specimens was detected using immunohistochemistry staining. The check points of G2/M-phase fractions, cyclin B, and pCdk1 (Y15) were analyzed using Western immunoblotting.

RESULTS

Compared to low-grade (grade I/II) gliomas, significant differences in the Ki-67, cyclin B, G2/M-phase, and S+G2/M-phase expressions were found in high-grade (grade III/IV) gliomas. Furthermore, receiver operating characteristic (ROC) analysis indicated optimal cutoff points for the G2/M-phase and S+G2/M-phase fractions of 13.47 and 17.26%, respectively, which can be used to differentiate cases with low- and high-grade gliomas. Additionally, both G2/M-phase and S+G2/M-phase fractions had significant association with the expression of Ki-67 in the gliomas. The gliomas were classified by the DNA content. We found that patients with high-grade glioma had worse survival rate than patients with low-grade glioma. Meanwhile, ROC curve analysis gave cutoffs for G2/M-phase of 9.4% and for S+G2/M-phase fractions of 15.04% as best predicting survival. The patients with glioma had poor survival when the levels of G2/M-phase and S+G2/M-phase were more than 9.4 and 15.04%, respectively. In contrast, no significant association between the DNA content of glioma patients and their age, tumor recurrence, and tumor size was found.

DISCUSSION

Our results indicate that flow cytometry analysis for G2/M-phase and S+G2/M-phase fractions can be used for tumor grading for rapidly differentiating low- from high-grade gliomas.

CDKN3 mRNA as a Biomarker for Survival and Therapeutic Target in Cervical Cancer

The cyclin-dependent kinase inhibitor 3 (CDKN3) gene, involved in mitosis, is upregulated in cervical cancer (CC). We investigated CDKN3 mRNA as a survival biomarker and potential therapeutic target for CC. CDKN3 mRNA was measured in 134 CC and 25 controls by quantitative PCR. A 5-year survival study was conducted in 121 of these CC patients. Furthermore, CDKN3-specific siRNAs were used to investigate whether CDKN3 is involved in proliferation, migration, and invasion in CC-derived cell lines (SiHa, CaSki, HeLa). CDKN3 mRNA was on average 6.4-fold higher in tumors than in controls (p = 8 x 10⁻⁶, Mann-Whitney). A total of 68.2% of CC patients over expressing CDKN3 gene (fold change ≥ 17) died within two years of diagnosis, independent of the clinical stage and HPV type (Hazard Ratio = 5.0, 95% CI: 2.5–10, p = 3.3 x 10⁻⁶, Cox proportional-hazards regression). In contrast, only 19.2% of the patients with lower CDKN3 expression died in the same period. In vitro inactivation of CDKN3 decreased cell proliferation on average 67%, although it had no effect on cell migration and invasion. CDKN3 mRNA may be a good survival biomarker and potential therapeutic target in CC.

A 3'UTR polymorphism modulates mRNA stability of the oncogene and drug target Polo-like Kinase 1

BACKGROUND

The Polo-like Kinase 1 (PLK1) protein regulates cell cycle progression and is overexpressed in many malignant tissues. Overexpression is associated with poor prognosis in several cancer entities, whereby expression of PLK1 shows high inter-individual variability. Although PLK1 is extensively studied, not much is known about the genetic variability of the PLK1 gene. The function of PLK1 and the expression of the corresponding gene could be influenced by genomic variations. Hence, we investigated the gene for functional polymorphisms. Such polymorphisms could be useful to investigate whether PLK1 alters the risk for and the course of cancer and they could have an impact on the response to PLK1 inhibitors.

METHODS

The coding region, the 5' and 3'UTRs and the regulatory regions of PLK1 were systematically sequenced. We determined the allele frequencies and genotype distributions of putatively functional SNPs in 120 Caucasians and analyzed the linkage and haplotype structure using Haploview. The functional analysis included electrophoretic mobility shift assay (EMSA) for detected variants of the silencer and promoter regions and reporter assays for a 3'UTR polymorphism.

RESULTS

Four putatively functional polymorphisms were detected and further analyzed, one in the silencer region (rs57973275), one in the core promoter region (rs16972787), one in intron 3 (rs40076) and one polymorphism in the 3'untranslated region (3'UTR) of PLK1 (rs27770). Alleles of rs27770 display different secondary mRNA structures and showed a distinct allele-dependent difference in mRNA stability with a significantly higher reporter activity of the A allele (p < 0.01).

CONCLUSION

The present study provides evidence that at least one genomic variant of PLK1 has functional properties and influences expression of PLK1. This suggests polymorphisms of the PLK1 gene as an interesting target for further studies that might affect cancer risk, tumor progression as well as the response to PLK1 inhibitors.

Antiproliferative in vitro effects of BI 2536-mediated PLK1 inhibition on cervical adenocarcinoma cells

Cervical adenocarcinoma is one of the most common gynecological malignancies. Despite the improvements in multimodality treatment, advanced disease is still associated with a significantly poor prognosis making the search for more effective therapeutic agents imperative. BI 2536, an unambiguous inhibitor of Polo-like kinase 1 (PLK1), has shown anticancer activity in a variety of tumor cell types. Herein, we present more evidence of the antiproliferative effects of this drug on HeLa cells. Nanomolar concentrations (10-100 nmol/l) of the drug significantly decreased cell proliferation and clonogenic capacity. Our results also demonstrate that inhibition of PLK1 promoted G2/M arrest and resulted in a dramatic increase in the mitotic index after 24 h of treatment. Apoptosis onset was evinced by the accumulation of a sub-G1 population as well as by a significant increase in caspase-3 activity at longer periods of exposure. Taken together, our results reinforce the prospect of directing against PLK1 as a potential therapeutic target to be evaluated in different preclinical models for cervical carcinoma.

LIM kinase inhibition reduces breast cancer growth and invasiveness but systemic inhibition does not reduce metastasis in mice

Metastasis is the major cause of morbidity and mortality in cancer patients. An understanding of the genes that regulate metastasis and development of therapies to target these genes is needed urgently. Since members of the LIM kinase (LIMK) family are key regulators of the actin cytoskeleton and are involved in cell motility and invasion, LIMK is considered to be a good therapeutic target for metastatic disease. Here we investigated the consequences of LIMK inhibition on growth and metastasis of human and mouse mammary tumors. LIMK activity was reduced in tumor cells by expression of dominant-negative LIMK1, by RNA interference or with a selective LIMK inhibitor. The extent of phosphorylation of the LIMK substrate, cofilin, of proliferation and invasion in 2D and 3D culture and of tumor growth and metastasis in mice were assessed. Inhibition of LIMK activity efficiently reduced the pro-invasive properties of tumor cells in vitro. Tumors expressing dominant-negative LIMK1 grew more slowly and were less metastatic in mice. However, systemic administration of a LIMK inhibitor did not reduce either primary tumor growth or spontaneous metastasis. Surprisingly, metastasis to the liver was increased after administration of the inhibitor. These data raise a concern about the use of systemic LIMK inhibitors for the treatment of metastatic breast cancer.

Rhein Lysinate Induced S-Phase Arrest and Increased the Anti-Tumor Activity of 5-FU in HeLa Cells

Rhein lysinate (RHL), easily dissolved in water, is one of the anthraquinones, and has been shown to have anti-tumor activity in different human cancer cell lines. In the present study, we observed that RHL could cause vacuolar degeneration in HeLa cells, which was not observed in human umbilical vein endothelial cells (HUVECs) and other cell lines (SKOV-3 and SK-BR-3). Therefore, the purpose of this study was to investigate the anti-tumor effect of rhein lysinate on human cervix cancer HeLa cells. The results indicated that RHL could induce HeLa cell S-phase arrest and RHL (higher than 80 μM) also induced HeLa cell G2/M-phase arrest in a dose-dependent manner. Compared to the HeLa cells, RHL induced HUVECs G1-phase arrest at all dose levels tested in a dose-dependent manner. Treatment with RHL led to a significant S or G2/M-phase arrest through promoting the expression of p53 and p21 and the phosphorylation of p53. Moreover, 80 μM RHL could increase 5-FU anti-tumor activity. In conclusion, RHL could be a novel chemotherapeutic drug candidate for the treatment of human cervix cancer in the future.

A functional cooperativity between Aurora A kinase and LIM kinase1: implication in the mitotic process

Aurora kinase A (Aur-A), a mitotic kinase, regulates initiation of mitosis through centrosome separation and proper assembly of bipolar spindles. LIM kinase 1 (LIMK1), a modulator of actin and microtubule dynamics, is involved in the mitotic process through inactivating phosphorylation of cofilin. Phosphorylated LIMK1 is recruited to the centrosomes during early prophase, where it colocalizes with γ-tubulin. Here, we report a novel functional cooperativity between Aur-A and LIMK1 through mutual phosphorylation. LIMK1 is recruited to the centrosomes during early prophase and then to the spindle poles, where it colocalizes with Aur-A. Aur-A physically associates with LIMK1 and activates it through phosphorylation, which is important for its centrosomal and spindle pole localization. Aur-A also acts as a substrate of LIMK1, and the function of LIMK1 is important for its specific localization and regulation of spindle morphology. Taken together, the novel molecular interaction between these two kinases and their regulatory roles on one another's function may provide new insight on the role of Aur-A in manipulation of actin and microtubular structures during spindle formation.

Small interfering RNA-mediated knockdown of polo-like kinase 1 promotes apoptosis in human hepatocellular carcinoma cell line BCL-7402

AIM: To investigate the effect of small interfering RNA (siRNA)-mediated Polo-like kinase 1 (Plk1) gene silencing on p53 expression and cell apoptosis in human hepatocellular carcinoma cell line BCL-7402, and to explore the feasibility of targeting the human Plk1 gene as a therapeutic strategy for hepatocellular carcinoma.

METHODS: Two siRNA sequences (siRNA1 and siRNA2) targeting the human Plk1 gene were designed and synthesized. BCL-7402 cells were transfected with blank control, negative control, siRNA1 or siRNA2 via lipofection. After transfection, reverse transcription-polymerase chain reaction (RT- PCR) was used to examine the expression of Plk1 mRNA , and Western blot was used to examine the expression of Plk1 and P53 proteins in transfected BCL-7402 cells. Cell cycle distribution and apoptosis of transfected cells were monitored by flow cytometry (FCM). The ultrastructural changes of transfected BCL-7402 cells were observed by transmission electron microscopy (TEM).

RESULTS: BCL-7402 cells transfected with low doses of siRNAs targeting the Plk1 gene showed greatly decreased levels of Plk1 mRNA and protein. In the siRNA1 group, Plk1 mRNA expression was reduced by 51% and 62% and Plk1 protein expression by 65% and 81% 24 and 48 h after transfection (all P < 0.01). In the siRNA2 group, Plk1 mRNA expression was reduced by 42% and 56% and Plk1 protein expression by 51% and 65% 24 and 48 h after transfection (all P < 0.01). P53 protein levels increased obviously with the decrease in Plk1 protein levels (P < 0.01). The percentage of cells at G₂/M phase increased obviously 24 h after transfection (P < 0.01). Apoptosis rate increased remarkably and apoptotic phenotypes could be seen by TEM. in cells 48 h after transfection.

CONCLUSION: SiRNAs targeting the human Plk1 gene remarkably inhibited Plk1 expression, increased p53 gene expression, and promoted apoptosis, suggesting that the Plk1 gene plays important roles in cell cycle control and apoptosis of BCL-7402 cells.

Pathway profiling and rational trial design for studies in advanced stage cervical carcinoma: a review and a perspective

Multiple genetic abnormalities will have occurred in advanced cervical cancer and multiple targeting is likely to be needed to control tumor growth. To date, dominant therapeutic targets under scrutiny for cervical cancer treatment have been EGFR pathway and angiogenesis inhibition as well as anti-HPV vaccines. The potentially most effective targets to be blocked may be downstream from the membrane receptor or at the level of the nucleus. Alterations of the pathways involved in DNA repair and in checkpoint activations, as well as the specific site of HPV genome integration, appear worth assessing. For genetic mutational analysis, complete exon sequencing may become the norm in the future but at this stage frequent mutations (that matter) can be verified by PCR analysis. A precise documentation of relevant alterations of a large spectrum of protein biomarkers can be carried out by reverse phase protein array (RPPA) or by multiplex analysis. Clinical decision-making on the drug(s) of choice as a function of the biological alteration will need input from bio-informatics platforms as well as novel statistical designs. Endpoints are yet to be defined such as the loss (or reappearance) of a predictive biomarker. Single or dual targeting needs to be explored first in relevant preclinical animal and in xenograft models prior to clinical deployment.