Investigation of Clinically Significant Molecular Aberrations in Patients with Prostate Cancer: Implications for Personalized Treatment, Prognosis and Genetic Testing.

The data on tumor molecular profiling of European patients with prostate cancer is limited. Our aim was to evaluate the prevalence and prognostic and predictive values of gene alterations in unselected patients with prostate cancer. The presence of gene alterations was assessed in patients with histologically confirmed prostate cancer using the ForeSENTIA® Prostate panel (Medicover Genetics), targeting 36 clinically relevant genes and microsatellite instability testing. The primary endpoint was the prevalence of gene alterations in homologous recombination repair (HRR) genes. Overall, 196 patients with prostate cancer were evaluated (median age 72.2 years, metastatic disease in 141 (71.9%) patients). Gene alterations were identified in 120 (61%) patients, while alteration in HRR genes were identified in 34 (17.3%) patients. The most commonly mutated HRR genes were ATM (17, 8.7%), BRCA2 (9, 4.6%) and BRCA1 (4, 2%). The presence of HRR gene alterations was not associated with advanced stage (p = 0.21), age at diagnosis (p = 0.28), Gleason score (p = 0.17) or overall survival (HR 0.72; 95% CI: 0.41-1.26; p = 0.251). We identified clinically relevant somatic gene alterations in European patients with prostate cancer. These molecular alterations have prognostic significance and therapeutic implications and/or may trigger genetic testing in selected patients. In the era of precision medicine, prospective research on the predictive role of these alterations for innovative treatments or their combinations is warranted.

A Comparison of Three Methods for the Detection of Circulating Tumor Cells in Patients with Early and Metastatic Breast Cancer.

BACKGROUND: We directly compared CTC detection rates and prognostic significance, using three different methods in patients with breast cancer (BC). METHODS: Early (n=200) and metastatic (n=164) patients were evaluated before initiating adjuvant or first-line chemotherapy, using the CellSearchTM System, an RT-qPCR for CK-19 mRNA detection and by double immunofluorescence (IF) microscopy using A45-B/B3 and CD45 antibodies. RESULTS: Using the CellSearchTM System, 37% and 16.5% of early BC patients were CTC-positive (at ≥1 and ≥2 CTCs/23 ml of blood), 18.0% by RT-qPCR and 16.9% by IF; no agreement was observed between methods. By the CellSearchTM 34.8% and 53.7% (at≥ 5 and ≥ 2 CTCs/7.5 ml) of metastatic patients were CTC-positive, 37.8% by RT-qPCR and 28.5% by IF. A significant agreement existed only between the CellSearchTM and RT-qPCR. In 60.8% of cases, differential EpCAM and CK-19 expression on CTCs by IF could explain the discrepancies between the CellSearchTM and RT-qPCR. CTC-positivity by either method was associated with decreased overall survival in metastatic patients. CONCLUSION: A significant concordance was observed between the CellSearchTM and RT-qPCR in metastatic but not in early BC. Discordant results could be explained in part by CTC heterogeneity. CTC detection by all methods evaluated had prognostic relevance in metastatic patients.

Evaluation of proliferation and apoptosis markers in circulating tumor cells of women with early breast cancer who are candidates for tumor dormancy.

INTRODUCTION: Clinical dormancy is frequently observed in breast cancer. In the present study, we aimed to characterize circulating tumor cells (CTCs) in dormancy candidates (DC) with early breast cancer in terms of proliferation and apoptosis. METHODS: Cytospins of peripheral blood mononuclear cells (PBMCs) were obtained from DC (n = 122) who were disease-free for at least 5 years and from metastatic patients (n = 40) who relapsed more than 5 years after surgery. Sequential samples from eight DC (n = 36) who maintained a prolonged disease-free status and from eight DC (n = 27) presenting late relapse during follow-up, were also analyzed. PBMCs were triple stained with a pancytokeratin, antibody along with anti-Ki67 and anti-M30 antibodies as proliferation and apoptosis markers, respectively. RESULTS: CTCs were identified in 40 (33%) of 122 DC and in 15 (37.5%) of 40 metastatic patients. In total, twenty-five (62.5%) DC had exclusively dormant (Ki67(-)/M30(-)), seven (17.5%) had proliferative Ki67(+)/M30(-), four (10%) had apoptotic Ki67(-)/M30(+) and four (10%) had both phenotypes of proliferative and apoptotic CTCs. In comparison, 53.4% of CTC-positive metastatic patients had exclusively dormant and 46.6% had proliferative CTCs; none had apoptotic CTCs (P = 0.039). Among all CTCs detected in DC patients, 82.4% were dormant, whereas in the nondormant population, 32.5% were proliferative and 67.5% apoptotic. The respective percentages in metastatic patients were 59.1%, 100% and 0% (P <0.0001). Moreover, apoptotic CTCs prevailed among nondormant CTCs detected in sequential samples from DC who remained in a prolonged disease-free status compared to those presenting late relapse during follow-up (70.6% versus 43.5% (P = 0.0002)). CONCLUSIONS: The apoptotic index of CTCs is increased during clinical dormancy, whereas the proliferation index is increased on relapse. In addition, apoptotic CTCs are more frequently encountered during follow-up in DC patients who remain disease-free compared to those with subsequent late relapse, suggesting that monitoring proliferation and apoptosis in CTCs during clinical dormancy merits further investigation as a tool for predicting late disease recurrence.

Comprehensive Analysis of CXCR4, JUNB, and PD-L1 Expression in Circulating Tumor Cells (CTCs) from Prostate Cancer Patients.

CXCR4, JUNB and PD-L1 are implicated in cancer progression and metastasis. The current study investigated these biomarkers in CTCs isolated from metastatic prostate cancer (mPCa) patients at the RNA and protein levels. CTCs were isolated from 48 mPCa patients using the Ficoll density gradient and ISET system (17 out of 48). The (CK/PD-L1/CD45) and (CK/CXCR4/JUNB) phenotypes were identified using two triple immunofluorescence stainings followed by VyCAP platform analysis. Molecular analysis was conducted with an EpCAM-dependent method for 25/48 patients. CK-8, CK-18, CK-19, JUNB, CXCR4, PD-L1, and B2M (reference gene) were analyzed with RT-qPCR. The (CK+/PD-L1+/CD45-) and the (CK+/CXCR4+/JUNB+) were the most frequent phenotypes (61.1% and 62.5%, respectively). Furthermore, the (CK+/CXCR4+/JUNB-) phenotype was correlated with poorer progression-free survival [(PFS), HR: 2.5, p = 0.049], while the (CK+/PD-L1+/CD45-) phenotype was linked to decreased overall survival [(OS), HR: 262.7, p = 0.007]. Molecular analysis revealed that 76.0% of the samples were positive for CK-8,18, and 19, while 28.0% were positive for JUNB, 44.0% for CXCR4, and 48.0% for PD-L1. Conclusively, CXCR4, JUNB, and PD-L1 were highly expressed in CTCs from mPCa patients. The CXCR4 protein expression was associated with poorer PFS, while PD-L1 was correlated with decreased OS, providing new biomarkers with potential clinical relevance.

Immune Checkpoint and EMT-Related Molecules in Circulating Tumor Cells (CTCs) from Triple Negative Breast Cancer Patients and Their Clinical Impact.

Triple negative breast cancer (TNBC) is the most aggressive breast cancer subtype. There are few targeted therapies for these patients, leading to an unmet need for new biomarkers. The present study aimed to investigate the expression of PD-L1, CTLA-4, GLU, and VIM in CTCs of TNBC patients. Ninety-five patients were enrolled in this study: sixty-four TNBC and thirty-one luminal. Of these patients, 60 were in the early stage, while 35 had metastatic disease. Protein expression was identified by immunofluorescence staining experiments and VyCAP analysis. All the examined proteins were upregulated in TNBC patients. The expression of the GLU+VIM+CK+ phenotype was higher (50%) in metastatic TNBC compared to early TNBC patients (17%) (p = 0.005). Among all the BC patients, a significant correlation was found between PD-L1+CD45-CK+ and CTLA-4+CD45-CK+ phenotypes (Spearman test, p = 0.024), implying an important role of dual inhibition in BC. Finally, the phenotypes GLU+VIM+CK+ and PD-L1+CD45-CK+ were associated with shorter OS in TNBC patients (OS: log-rank p = 0.048, HR = 2.9, OS: log-rank p < 0.001, HR = 8.7, respectively). Thus, PD-L1, CTLA-4, GLU, and VIM constitute significant biomarkers in TNBC associated with patients' outcome, providing new therapeutic targets for this difficult breast cancer subtype.

Prognostic Role of Circulating Tumor Cells in Patients with Metastatic Castration-Resistant Prostate Cancer Receiving Cabazitaxel: A Prospective Biomarker Study.

RATIONAL: Circulating tumor cells (CTCs) appear to be a promising tool for predicting the clinical outcome and monitoring the response to treatment in patients with solid tumors. The current study assessed the clinical relevance of monitoring CTCs in patients with metastatic castration resistant prostate cancer (mCRPC) treated with cabazitaxel. PATIENTS AND METHODS: Patients with histologically confirmed mCRPC who were previously treated with a docetaxel-containing regimen and experienced disease progression were enrolled in this multicenter prospective study. CTC counts were enumerated using the CellSearch system at baseline (before cabazitaxel initiation), after one cabazitaxel cycle (post 1st cycle) and at disease progression (PD). Patients were stratified into predetermined CTC-positive and CTC-negative groups. The phenotypic characterization was performed using double immunofluorescence staining with anti-CKs and anti-Ki67, anti-M30 or anti-vimentin antibodies. RESULTS: The median PFS and OS were 4.0 (range, 1.0-17.9) and 14.5 (range, 1.2-33.9) months, respectively. At baseline, 48 out of 57 (84.2%) patients had ≥1 CTCs/7.5 mL of peripheral blood (PB) and 37 (64.9%) had ≥5 CTCs/7.5 mL of PB. After one treatment cycle, 30 (75%) out of the 40 patients with available measurements had ≥1 detectable CTC/7.5 mL of PB and 24 (60%) ≥ 5CTCs/7.5 mL of PB; 12.5% of the patients with detectable CTCs at the baseline sample had no detectable CTCs after one treatment cycle. The detection of ≥5CTCs/7.5 mL of PB at baseline and post-cycle 1 was associated with shorter PFS and OS (p = 0.002), whereas a positive CTC status post-cycle 1 strongly correlated with poorer OS irrespective of the CTC cut-off used. Multivariate analysis revealed that the detection of non-apoptotic (CK+/M30-) CTCs at baseline is an independent predictor of shorter OS (p = 0.005). CONCLUSIONS: In patients with mCRPC treated with cabazitaxel, CTC counts both at baseline and after the first cycle retain their prognostic significance, implying that liquid biopsy monitoring might serve as a valuable tool for predicting treatment efficacy and survival outcomes.

Emerging Role of YAP and the Hippo Pathway in Prostate Cancer.

The Hippo pathway regulates and contributes to several hallmarks of prostate cancer (PCa). Although the elucidation of YAP function in PCa is in its infancy, emerging studies have shed light on the role of aberrant Hippo pathway signaling in PCa development and progression. YAP overexpression and nuclear localization has been linked to poor prognosis and resistance to treatment, highlighting a therapeutic potential that may suggest innovative strategies to treat cancer. This review aimed to summarize available data on the biological function of the dysregulated Hippo pathway in PCa and identify knowledge gaps that need to be addressed for optimizing the development of YAP-targeted treatment strategies in patients likely to benefit.

Spatio-Temporal Variation of Lung Cancer in Crete, 1992-2013. Economic or Health Crisis?

(1) Background: This is the first population-based study in Greece, with the aim to measure the changing trends of lung cancer (LC) and the associated risk factors before and after the economic crisis. Among the main objectives were the identification of LC hot spots and high-risk areas; (2) Methods: The study was conducted in Crete, the biggest island in Greece. Data (5057 LC cases) were collected from the Cancer Registry of Crete (CRC). The age-standardized incidence and mortality rates (ASIR, ASMR/100,000/year) were estimated, while additional indexes were used, including the adjusted Charlson's comorbidity index (CCI%), the deprivation index (HPI-2), and the exposure to outdoor air pollution (OAP). The analysis was performed for two time periods (Period A: 1992-2008; Period B: 2009-2013); (3) Results: ASIR presented a significant increase during the economic crisis, while an even higher increase was observed in ASMR (Period A: ASMR = 30.5/100,000/year; Period B: ASMR = 43.8/100,000/year; p < 0.001). After 2009, a significant increase in the observed LC hot spots was identified in several sub-regions in Crete (p = 0.04). The risk of LC mortality increased even more for smokers (RR = 5.7; 95%CI = 5.2-6.3) and those living in highly deprived geographical regions (RR = 5.4; 95%CI = 5.1-5.8) during the austerity period. The multiple effect of LC predictors resulted in adjusted RRs ranging from 0.7 to 5.7 within the island (p < 0.05); (4) Conclusions: The increased LC burden after the onset of the economic crisis, along with a changing pattern of LC predictors stressed the urgent need of geographically oriented interventions and cancer control programs focusing on the most deprived or vulnerable population groups.

Phenotypic Characterization of Circulating Tumor Cells Isolated from Non-Small and Small Cell Lung Cancer Patients.

In the present study, we evaluated the expression of JUNB and CXCR4 in circulating tumor cells (CTCs) of lung cancer patients and investigated whether these proteins have prognostic clinical relevance. Peripheral blood from 30 patients with non-small-cell lung cancer (NSCLC) was filtered using ISET membranes, and cytospins from 37 patients with small-cell lung cancer (SCLC) were analyzed using confocal and VyCAP microscopy. Both JUNB and CXCR4 were expressed in the vast majority of lung cancer patients. Interestingly, the phenotypic patterns differed between NSCLC and SCLC patients; the (CK+/JUNB+/CXCR4+) phenotype was present in 50% of NSCLC vs. 71% of SCLC patients. Similarly, the (CK+/JUNB+/CXCR4−) was present in 44% vs. 71%, the (CK+/JUNB−/CXCR4+) in 6% vs. 71%, and the (CK+/JUNB−/CXCR4−) phenotype in 38% vs. 84%. In NSCLC, the presence of ≥1 CTCs with the (CK+/JUNB+/CXCR4+) phenotype was associated with worse progression-free survival (PFS) (p = 0.007, HR = 5.21) while ≥2 with poorer overall survival (OS) (p < 0.001, HR = 2.16). In extensive stage SCLC patients, the presence of ≥4 CXCR4-positive CTCs was associated with shorter OS (p = 0.041, HR = 5.01). Consequently, JUNB and CXCR4 were expressed in CTCs from lung cancer patients, and associated with patients' survival, underlying their key role in tumor progression.

Myeloid-Derived Suppressor Cells in Prostate Cancer: Present Knowledge and Future Perspectives.

Several lines of research are being investigated to better understand mechanisms implicated in response or resistance to immune checkpoint blockade in prostate cancer (PCa). Myeloid-derived suppressor cells (MDSCs) have emerged as a major mediator of immunosuppression in the tumor microenvironment that promotes progression of various tumor types. The main mechanisms underlying MDSC-induced immunosuppression are currently being explored and strategies to enhance anti-tumor immune response via MDSC targeting are being tested. However, the role of MDSCs in PCa remains elusive. In this review, we aim to summarize and present the state-of-the-art knowledge on current methodologies to phenotypically and metabolically characterize MDSCs in PCa. We describe how these characteristics may be linked with MDSC function and may influence the clinical outcomes of patients with PCa. Finally, we briefly discuss emerging strategies being employed to therapeutically target MDSCs and potentiate the long-overdue improvement in the efficacy of immunotherapy in patients with PCa.

Dynamic changes of CTCs in patients with metastatic HR(+)/HER2(-) breast cancer receiving salvage treatment with everolimus/exemestane.

PURPOSE: Detection of CTCs represents a poor prognostic factor in patients with early and metastatic breast cancer (mBC) and treatment with everolimus-exemestane (E/E) is an established effective treatment in hormone receptor-positive/HER2-negative mBC patients. The effect of E/E on CTCs in mBC patients was prospectively investigated. METHODS: CTCs from 50 pre-treated patients with mBC receiving E/E were analyzed using the CellSearch (CS) platform and triple immunofluorescence (IF) staining for cytokeratin, M30 and Ki67 expression to assess their proliferative and apoptotic status. RESULTS: CTCs (by CS) were detected in 64% of patients before treatment and E/E administration resulted in their decreased prevalence [(n = 18; 36%, p = 0.004) and (n = 7; 19.4%, p = 0.019) post-1st and post-3rd treatment cycle, respectively] whereas it was significantly increased at disease progression (PD: 61%) compared to post-1st and post-3rd cycle (p = 0.049 and p = 0.021, respectively). Ki67-positive CTCs were detected in 60%, 60%, 17% and 50% of patients before treatment, post-1st, post-3rd cycle and at PD, respectively, while the opposite was observed for M30-positive CTCs (0% at baseline, 10% after the 1st cycle, 50% after the 3rd cycle and 0% at PD). The detection of even ≥ 1 CTC/5 ml after one cycle was associated with decreased PFS (3.3 vs 9.0 months, p = 0.025) whereas the detection of even ≥ 2 CTCs at PD was associated with decreased OS (32.4 vs 19.5 months; p = 0.009). CONCLUSIONS: The combination of E/E resulted in early elimination of proliferating CTCs in mBC patients and this effect was associated with a favorable clinical outcome.

Resistance to MET/VEGFR2 Inhibition by Cabozantinib Is Mediated by YAP/TBX5-Dependent Induction of FGFR1 in Castration-Resistant Prostate Cancer.

The overall goal of this study was to elucidate the role of FGFR1 induction in acquired resistance to MET and VEGFR2 inhibition by cabozantinib in prostate cancer (PCa) and leverage this understanding to improve therapy outcomes. The response to cabozantinib was examined in mice bearing patient-derived xenografts in which FGFR1 was overexpressed. Using a variety of cell models that reflect different PCa disease states, the mechanism underpinning FGFR1 signaling activation by cabozantinib was investigated. We performed parallel investigations in specimens from cabozantinib-treated patients to confirm our in vitro and in vivo data. FGFR1 overexpression was sufficient to confer resistance to cabozantinib. Our results demonstrate transcriptional activation of FGF/FGFR1 expression in cabozantinib-resistant models. Further analysis of molecular pathways identified a YAP/TBX5-driven mechanism of FGFR1 and FGF overexpression induced by MET inhibition. Importantly, knockdown of YAP and TBX5 led to decreased FGFR1 protein expression and decreased mRNA levels of FGFR1, FGF1, and FGF2. This association was confirmed in a cohort of hormone-naïve patients with PCa receiving androgen deprivation therapy and cabozantinib, further validating our findings. These findings reveal that the molecular basis of resistance to MET inhibition in PCa is FGFR1 activation through a YAP/TBX5-dependent mechanism. YAP and its downstream target TBX5 represent a crucial mediator in acquired resistance to MET inhibitors. Thus, our studies provide insight into the mechanism of acquired resistance and will guide future development of clinical trials with MET inhibitors.

Prostate Cancer: Quo Vadis?

Utility measures are urgently needed for clinical application of new, more sensitive diagnostics to reduce the risk of excessive intervention.

CD8+ PD-1+ T-cells and PD-L1+ circulating tumor cells in chemotherapy-naïve non-small cell lung cancer: towards their clinical relevance?

BACKGROUND: Since tumor cells may escape from immune surveillance through the programmed cell death 1 (PD-1)/programmed death ligand (PD-L)1 axis, this study was designed in order to evaluate whether there is a correlation between the levels of PD-1+ and PD-L1+-expressing immune cells (ICs) and circulating tumor cells (CTCs) in patients with non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Peripheral blood was obtained from 37 chemotherapy-naïve patients with metastatic NSCLC before treatment. PD-1 and PD-L1 expression was evaluated (1) on ICs with anti-tumor function (CD4+ and CD8+ T-cells, B-cells, monocytes/dendritic cells) using flow cytometry, (2) on CTCs by immunofluorescence and (3) on cells from tumor tissues by immunohistochemistry. The levels of PD-1+ and PD-L1+-expressing ICs were correlated with progression-free survival (PFS). RESULTS: The presence of PD-1+ CD8+ cells, with reduced interferon (IFN)-γ expression, but not other ICs, were positively correlated with PD-L1+ CTCs (p < 0.04). Increased percentages of PD-1+ CD8+ T-cells, were associated with a worse response to treatment (p = 0.032) and shorter PFS (p = 0.023) which, in multivariate analysis, was revealed as an independent predictor for decreased PFS [hazard ratio (HR): 4.1, p = 0.0007]. CONCLUSION: The results of the current study, for first time, provide evidence for a possible interaction between ICs and CTCs in NSCLC patients via the PD-1/PD-L1 axis and strongly support that the levels of PD-1+ CD8+ in these patients may be of clinical relevance.

Machine learning and data mining frameworks for predicting drug response in cancer: An overview and a novel in silico screening process based on association rule mining.

A major challenge in cancer treatment is predicting the clinical response to anti-cancer drugs on a personalized basis. The success of such a task largely depends on the ability to develop computational resources that integrate big "omic" data into effective drug-response models. Machine learning is both an expanding and an evolving computational field that holds promise to cover such needs. Here we provide a focused overview of: 1) the various supervised and unsupervised algorithms used specifically in drug response prediction applications, 2) the strategies employed to develop these algorithms into applicable models, 3) data resources that are fed into these frameworks and 4) pitfalls and challenges to maximize model performance. In this context we also describe a novel in silico screening process, based on Association Rule Mining, for identifying genes as candidate drivers of drug response and compare it with relevant data mining frameworks, for which we generated a web application freely available at: https://compbio.nyumc.org/drugs/. This pipeline explores with high efficiency large sample-spaces, while is able to detect low frequency events and evaluate statistical significance even in the multidimensional space, presenting the results in the form of easily interpretable rules. We conclude with future prospects and challenges of applying machine learning based drug response prediction in precision medicine.

A Deep Learning Framework for Predicting Response to Therapy in Cancer.

A major challenge in cancer treatment is predicting clinical response to anti-cancer drugs on a personalized basis. Using a pharmacogenomics database of 1,001 cancer cell lines, we trained deep neural networks for prediction of drug response and assessed their performance on multiple clinical cohorts. We demonstrate that deep neural networks outperform the current state in machine learning frameworks. We provide a proof of concept for the use of deep neural network-based frameworks to aid precision oncology strategies.

Prognostic significance of CEACAM5mRNA-positive circulating tumor cells in patients with metastatic colorectal cancer.

PURPOSE: Τo evaluate the clinical relevance of CEACAM5mRNA-positive circulating tumor cells (CTCs) in patients with metastatic colorectal cancer (mCRC). METHODS: Peripheral blood was obtained from 436 patients with mCRC before the initiation of systemic therapy. A second sample was obtained on treatment assessment from 296 (67.9%) patients. The detection of CEACAM5mRNA-positive CTCs was performed using a real-time PCR assay. RESULTS: The patients' median age was 67 years and PS (EGOG 0-1) 92%; KRAS exon 2 and BRAFV600E mutated primary tumors were identified in 31.9% and 6.4% of the tested patients, respectively, whereas metastasectomy was performed in 17.7% of the patients. Circulating CEACAM5mRNA-positive CTCs were detected in 125 (28.7%) and 85 (28.7%) patients at baseline and on treatment assessment, respectively. The detection of CEACAM5mRNA-positive cells was revealed, in multivariate analysis, as an independent prognostic factor associated with decreased PFS (HR 1.6; 95% CI 1.1-2.5; p = 0.026) and OS (HR 2.2; 95% CI 1.3-3.2; p < 0.001). The detection of CEACAM5mRNA-positive CTCs in patients with KRAS and BRAFV600E mutations was correlated with shorter PFS (p = 0.041 and p = 0.022, respectively). Moreover, OS was significantly shorter in patients with CEACAM5+/KRAS mutations compared to those with CEACAM5+/KRAS wt tumors (p = 0.023). CONCLUSIONS: Detection of peripheral blood CEACAM5mRNA-positive CTCs is an adverse prognostic factor correlated with poor clinical outcome in patients with mCRC, especially in patients with KRAS and BRAF mutated tumors.

Evaluation of PD-L1/PD-1 on circulating tumor cells in patients with advanced non-small cell lung cancer.

BACKGROUND: Circulating tumor cells (CTCs) could escape from the immune system through the programmed death-ligand 1 (PD-L1)/programmed cell death protein 1 (PD-1) axis leading to the development of metastasis. The current study investigated the expression of PD-1/PD-L1 on CTCs isolated from non-small cell lung cancer (NSCLC) patients treated with chemotherapy. PATIENTS AND METHODS: CTCs were isolated from 30 chemo-naïve stage IV NSCLC patients before and after front-line chemotherapy using the ISET filtration platform. CTCs were detected by Giemsa and immunofluorescence (IF) staining. Samples were analyzed with the ARIOL system. RESULTS: Giemsa staining revealed that 28 (93.3%) out of 30 and 9 (81.8%) out of 11 patients had detectable CTCs at baseline and after the third chemotherapy cycle, respectively. Cytokeratin (CK)+/CD45- CTCs by IF could be detected in 17 of 30 (56.7%) patients at baseline and in 8 of 11 (72.7%) after the third chemotherapy cycle. Spearman analysis revealed a significant correlation (p = 0.001) between Giemsa-positive and IF-positive (CK+/CD45-) CTCs. At baseline, PD-1 and PD-L1 expression was observed in 53% and in 47% CK-positive patients, respectively. After the third treatment cycle the corresponding numbers were 13% and 63% respectively. Median progression-free survival (PFS) was significantly shorter in patients with >3 PD-1(+) CTCs at baseline compared with those with <3 PD-1(+) CTCs (p = 0.022) as well as in patients with >1 Giemsa-positive tumor cells (p = 0.025). CONCLUSION: PD-1(+) and PD-L1(+) CTCs could be detected before and after front-line chemotherapy in patients with metastatic NSCLC. The presence of high PD-1(+) CTC numbers before treatment is associated with a poor patient clinical outcome.

Nab-paclitaxel as second-line treatment in advanced gastric cancer: a multicenter phase II study of the Hellenic Oncology Research Group.

BACKGROUND: This study evaluated the safety and efficacy of nab-paclitaxel as second-line treatment in patients with advanced gastric adenocarcinoma. METHODS: Thirty-nine pretreated patients [33 with taxane-based regimens (docetaxel, cisplatin, and fluorouracil)] and 6 with combination of fluoropyrimidines plus cisplatin with locally advanced inoperable and metastatic gastric and gastroesophageal junction adenocarcinoma were treated with weekly nab-paclitaxel (150 mg/m2 d1, d8, d15 in cycles of 28 days). RESULTS: Partial response (PR) was documented in nine patients (23.1%; 95% confidence interval 10.1-37.2%), stable disease (SD) in 11 (28.2%) and disease progression in 18 (46.2%). The disease control rate (SD + PR + complete response) was 51.3%. Grade 3 and 4 neutropenia occurred in 10.2% and 5.1% of patients, respectively; grade 3 anemia in 5.1%; grade 3 neurotoxicity in 5.1%; and grade 2 pain in 5.1%. The median progression-free survival was 3.0 months (range 0.3-13.6) and the median overall survival 6.8 months (range 0.3-22). CONCLUSION: Nab-paclitaxel as second-line treatment in locally advanced inoperable or metastatic gastric and gastroesophageal junction carcinoma is an active chemotherapy regimen with a manageable toxicity profile and merits further evaluation.

MKAD-21 Suppresses the Oncogenic Activity of the miR-21/PPP2R2A/ERK Molecular Network in Bladder Cancer.

Bladder cancer represents a disease associated with significant morbidity and mortality. MiR-21 has been found to have oncogenic activity in multiple cancers, including bladder cancer, whereas inhibition of its expression suppresses tumor growth. Here, we examine the molecular network regulated by miR-21 in bladder cancer and evaluate the effects of i.v. and i.p. administration of a novel miR-21 chemical inhibitor in vivo LNA miR-21 reduced the oncogenic potential of bladder cancer cells, whereas the MKAD-21 chemically modified antisense oligo against miR-21 dose-dependently blocked xenograft growth. I.v. administration of LNA miR-21 was more effective in suppressing tumor growth than was i.p. administration. Integration of computational and transcriptomic analyses in a panel of 28 bladder cancer lines revealed a 15-gene signature that correlates with miR-21 levels. Protein Phosphatase 2 Regulatory Subunit Balpha (PPP2R2A) was one of these 15 genes and was experimentally validated as a novel miR-21 direct target gene. Gene network and molecular analyses showed that PPP2R2A is a potent negative regulator of the ERK pathway activation and bladder cancer cell proliferation. Importantly, we show that PPP2R2A acts as a mediator of miR-21-induced oncogenic effects in bladder cancer. Integrative analysis of human bladder cancer tumors and a large panel of human bladder cancer cell lines revealed a novel 15-gene signature that correlates with miR-21 levels. Importantly, we provide evidence that PPP2R2A represents a new miR-21 direct target and regulator of the ERK pathway and bladder cancer cell growth. Furthermore, i.v. administration of the MKAD-21 inhibitor effectively suppressed tumor growth through regulation of the PPP2R2A-ERK network in mice. Mol Cancer Ther; 17(7); 1430-40. ©2018 AACR.