Applications of CRISPR Technology to Breast Cancer and Triple Negative Breast Cancer Research.

Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) technology has transformed oncology research in many ways. Breast cancer is the most prevalent malignancy globally and triple negative breast cancer (TNBC) is one of the most aggressive subtypes with numerous challenges still to be faced. In this work, we have explained what CRISPR consists of and listed its applications in breast cancer while focusing on TNBC research. These are disease modelling, the search for novel genes involved in tumour progression, sensitivity to drugs and immunotherapy response, tumour fitness, diagnosis, and treatment. Additionally, we have listed the current delivery methods employed for the delivery of CRISPR systems in vivo. Lastly, we have highlighted the limitations that CRISPR technology is subject to and the future directions that we envisage. Overall, we have provided a round summary of the aspects concerning CRISPR in breast cancer/TNBC research.

MicroRNAs Present in Malignant Pleural Fluid Increase the Migration of Normal Mesothelial Cells In Vitro and May Help Discriminate between Benign and Malignant Effusions.

The sensitivity of pleural fluid (PF) analyses for the diagnosis of malignant pleural effusions (MPEs) is low to moderate. Knowledge about the pathobiology and molecular characteristics of this condition is limited. In this study, the crosstalk between stromal cells and tumor cells was investigated in vitro in order to reveal factors that are present in PF which can mediate MPE formation and aid in discriminating between benign and malignant etiologies. Eighteen PF samples, in different proportions, were exposed in vitro to mesothelial MeT-5A cells to determine the biological effects on these cells. Treatment of normal mesothelial MeT-5A cells with malignant PF increased cell viability, proliferation, and migration, and activated different survival-related signaling pathways. We identified differentially expressed miRNAs in PF samples that could be responsible for these changes. Consistently, bioinformatics analysis revealed an enrichment of the discovered miRNAs in migration-related processes. Notably, the abundance of three miRNAs (miR-141-3p, miR-203a-3, and miR-200c-3p) correctly classified MPEs with false-negative cytological examination results, indicating the potential of these molecules for improving diagnosis. Malignant PF produces phenotypic and functional changes in normal mesothelial cells. These changes are partly mediated by certain miRNAs, which, in turn, could serve to differentiate malignant from benign effusions.

PLA2G12A as a Novel Biomarker for Colorectal Cancer with Prognostic Relevance.

Metastasis is the leading cause of colorectal cancer (CRC)-related deaths. Therefore, the identification of accurate biomarkers predictive of metastasis is needed to better stratify high-risk patients to provide preferred management and reduce mortality. In this study, we identified 13 new genes that modified circulating tumor cell numbers using a genome-wide genetic screen in a whole animal CRC model. Candidate genes were subsequently evaluated at the gene expression level in both an internal human CRC cohort of 153 patients and an independent cohort from the TCGA including 592 patients. Interestingly, the expression of one candidate, PLA2G12A, significantly correlated with both the time to recurrence and overall survival in our CRC cohort, with its low expression being an indicator of a poor clinical outcome. By examining the TCGA cohort, we also found that low expression of PLA2G12A was significantly enriched in epithelial-mesenchymal transition signatures. Finally, the candidate functionality was validated in vitro using three different colon cancer cell lines, revealing that PLA2G12A deficiency increases cell proliferation, migration, and invasion. Overall, our study identifies PLA2G12A as a prognostic biomarker of early-stage CRC, providing evidence that its deficiency promotes tumor growth and dissemination.

Total neoadjuvant therapy with or without aflibercept in rectal cancer: 3-year results of GEMCAD-1402.

BACKGROUND: The results of the Grupo Español Multidisciplinar en Cáncer Digestivo (GEMCAD)-1402 phase II randomized trial suggested that adding aflibercept to modified fluorouracil, oxaliplatin, and leucovorin (mFOLFOX6) induction, followed by chemoradiation and surgery, could increase the pathological complete response (pCR) rate in patients with high-risk, locally advanced rectal cancer. Here we update results up to 3 years of follow-up and evaluate the predictive value of consensus molecular subtypes identified with immunohistochemistry (IHC). METHODS: Patients with magnetic resonance imaging-defined T3c-d and/or T4 and/or N2 rectal adenocarcinoma in the middle or distal third were randomly assigned to mFOLFOX6 induction, with aflibercept (mF+A; n = 115) or without aflibercept (mF; n = 65), followed by capecitabine plus radiotherapy and surgery. The risk local relapse, distant metastases, disease-free survival (DFS), and overall survival (OS) were estimated at 3 years. Selected samples were classified via IHC into immune-infiltrate, epithelial, or mesenchymal subtypes. RESULTS: mF+A and mF had 3-year DFS of 75.2% (95% confidence interval [CI] = 66.1% to 82.2%) and 81.5% (95% CI = 69.8% to 89.1%), respectively; 3-year OS of 89.3% (95% CI = 82.0% to 93.8%) and 90.7% (95% CI = 80.6% to 95.7%), respectively; 3-year cumulative local relapse incidences of 5.2% (95% CI = 1.9% to 11.0%) and 6.1% (95% CI = 1.7% to 15.0%), respectively; and 3-year cumulative distant metastases rates of 17.3% (95% CI = 10.9% to 25.5%) and 16.9% (95% CI = 8.7% to 28.2%), respectively. pCRs were achieved in 27.5% (n = 22 of 80) and 0% (n = 0 of 10) of patients with epithelial and mesenchymal subtypes, respectively. CONCLUSION: Adding aflibercept to mFOLFOX6 induction was not associated with improved DFS or OS. Our findings suggested that consensus molecular subtypes identified with IHC subtypes could be predictive of pCR with this treatment.

Evolution of RAS Mutations in Cell-Free DNA of Patients with Tissue RAS Wild-Type Metastatic Colorectal Cancer Receiving First-Line Treatment: The PERSEIDA Study.

The serial analysis of cell-free DNA (cfDNA) enables minimally invasive monitoring of tumor evolution, providing continuous genetic information. PERSEIDA was an observational, prospective study assessing the cfDNA RAS (KRAS/NRAS) mutational status evolution in first-line, metastatic CRC, RAS wild-type (according to baseline tumor tissue biopsy) patients. Plasma samples were collected before first-line treatment, after 20 ± 2 weeks, and at disease progression. One hundred and nineteen patients were included (102 received panitumumab and chemotherapy as first-line treatment-panitumumab subpopulation). Fifteen (12.6%) patients presented baseline cfDNA RAS mutations (n = 14 [13.7%], panitumumab subpopulation) (mutant allele fraction ≥0.02 for all results). No patients presented emergent mutations (cfDNA RAS mutations not present at baseline) at 20 weeks. At disease progression, 11 patients (n = 9; panitumumab subpopulation) presented emergent mutations (RAS conversion rate: 19.0% [11/58]; 17.7% [9/51], panitumumab subpopulation). In contrast, three (5.2%) patients presenting baseline cfDNA RAS mutations were RAS wild-type at disease progression. No significant associations were observed between overall response rate or progression-free survival and cfDNA RAS mutational status in the total panitumumab subpopulation. Although, in patients with left-sided tumors, a significantly longer progression-free survival was observed in cfDNA RAS wild-type patients compared to those presenting cfDNA RAS mutations at any time. Continuous evaluation of RAS mutations may provide valuable insights on tumor molecular dynamics that can help clinical practice.

Are Transcription Factors Plausible Oncotargets for Triple Negative Breast Cancers?

Breast cancer (BC) is the most diagnosed cancer worldwide and one of the main causes of cancer deaths. BC is a heterogeneous disease composed of different BC intrinsic subtypes such as triple-negative BC (TNBC), which is one of the most aggressive subtypes and which lacks a targeted therapy. Recent comprehensive analyses across cell types and cancer types have outlined a vast network of protein-protein associations between transcription factors (TFs). Not surprisingly, protein-protein networks central to oncogenesis and disease progression are highly altered during TNBC pathogenesis and are responsible for the activation of oncogenic programs, such as uncontrollable proliferation, epithelial-to-mesenchymal transition (EMT) and stemness. From the therapeutic viewpoint, inhibiting the interactions between TFs represents a very significant challenge, as the contact surfaces of TFs are relatively large and featureless. However, promising tools have emerged to offer a solution to the targeting problem. At the clinical level, some TF possess diagnostic and prognostic value in TNBC. In this review, we outline the recent advances in TFs relevant to TNBC growth and progression. Moreover, we highlight different targeting approaches to inhibit these TFs. Furthermore, the validity of such TFs as clinical biomarkers has been explored. Finally, we discuss how research is likely to evolve in the field.

Effect of aflibercept plus FOLFIRI and potential efficacy biomarkers in patients with metastatic colorectal cancer: the POLAF trial.

BACKGROUND: Aflibercept is an antiangiogenic drug against metastatic colorectal cancer (mCRC) combined with 5-fluorouracil/leucovorin/irinotecan (FOLFIRI); however, no antiangiogenic biomarker has yet been validated. We assessed aflibercept plus FOLFIRI, investigating the biomarker role of baseline vascular endothelial growth factor A (VEGF-A) and angiotensin-converting enzyme (ACE). METHODS: Phase II trial in oxaliplatin-treated mCRC patients who received aflibercept plus FOLFIRI. The reported 135 ng/mL ACE cut-off was used and ROC analysis was performed to assess the optimal VEGF-A cut-off for progression-free survival (PFS). Overall survival (OS), time to progression (TTP), time to treatment failure (TTF), overall response rate (ORR) and disease control rate (DCR) were also assessed. RESULTS: In total, 101 patients were followed for a median of 12 (6-17) months. The 1941 pg/mL VEGF-A was an optimal cut-off, with a longer median PFS when VEGF-A was <1941 versus ≥1941 pg/mL (9 versus 4 months). Patients with VEGF-A < 1941 pg/mL showed longer median OS (19 versus 8 months), TTP (9 versus 4 months) and TTF (8 versus 4 months), along with higher ORR (26% versus 9%) and DCR (81% versus 55%). No differences were identified according to ACE levels. CONCLUSIONS: This study supports aflibercept plus FOLFIRI benefits, suggesting VEGF-A as a potential biomarker to predict better outcomes.

Upfront primary tumour resection and survival in synchronous metastatic colorectal cancer according to primary tumour location and RAS status: Pooled analysis of the Spanish Cooperative Group for the Treatment of Digestive Tumours (TTD).

INTRODUCTION: Retrospective studies and meta-analyses suggest that upfront primary tumour resection (UPTR) confers a survival benefit in patients with asymptomatic unresectable metastatic colorectal cancer (mCRC) undergoing chemotherapy, however a consensus of its role in routine clinical practice in the current era of targeted therapies is lacking. This retrospective study aimed to analyse the survival benefit of UPTR in terms of tumour location and mutational status, in patients with synchronous mCRC receiving chemotherapy and targeted therapy. PATIENTS AND METHODS: Survival was analysed in a pooled cohort of synchronous mCRC patients treated with a first-line anti-VEGF or anti-EGFR inhibitor in seven trials of the Spanish TTD group, according to UPTR, tumour-sidedness and mutational profiling. RESULTS: Of 1334 eligible patients, 642 (48%) had undergone UPTR. UPTR was associated with significantly longer overall survival (OS; 25.0 vs 20.3 months; HR 1.30, 95%CI 1.15-1.48; p < 0.0001). UPTR was associated with significant OS benefit in both left-sided (HR 1.38, 95%CI 1.13-1.69; p = 0.002) and right-sided (HR 1.39, 95%CI 1.00-1.94; p = 0.049) tumours, RASwt (HR 1.29, 95%CI 1.05-1.60; p = 0.016) and BRAFwt (HR 1.49, 95%CI 1.21-1.84; p = 0.0002) tumours, and treatment with anti-EGFRs (HR 1.47, 95%CI 1.13-1.92; p = 0.004) and anti-VEGFs (HR 1.25, 95%CI 1.08-1.44; p = 0.003). Multivariate analysis identified number of metastatic sites, RAS status, primary tumour location and UPTR as independent prognostic factors for OS. CONCLUSION: Considering the selection bias inherent to this study, our results support UPTR before first-line anti-EGFR or anti-VEGF targeted therapy in right and left-sided asymptomatic unresectable synchronous mCRC patients. RAS/BRAF mutational status may also influence UPTR function.

Microenvironmental Reactive Oxygen Species in Colorectal Cancer: Involved Processes and Therapeutic Opportunities.

Colorectal cancer (CRC) is the fourth most common cause of cancer deaths worldwide. Although screening programs have reduced mortality rates, there is a need for research focused on finding the main factors that lead primary CRC to progress and metastasize. During tumor progression, malignant cells modify their habitat, corrupting or transforming cells of different origins and creating the tumor microenvironment (TME). Cells forming the TME like macrophages, neutrophils, and fibroblasts generate reactive oxygen species (ROS) that modify the cancer niche. The effects of ROS in cancer are very diverse: they promote cellular proliferation, epithelial-to-mesenchymal transition (EMT), evasion of cell death programs, migration, and angiogenesis. Due to the multifaceted role of ROS in cancer cell survival and function, ROS-modulating agents such as antioxidants or pro-oxidants could have therapeutic potential in cancer prevention and/or as a complement to systemic treatments. In this review, we will examine the main ROS producer cells and their effects on cancer progression and metastasis. Furthermore, we will enumerate the latest clinical trials where pro-oxidants and antioxidants have therapeutic uses in CRC.

Diving into the Pleural Fluid: Liquid Biopsy for Metastatic Malignant Pleural Effusions.

Liquid biopsy is emerging as a promising non-invasive diagnostic tool for malignant pleural effusions (MPE) due to the low sensitivity of conventional pleural fluid (PF) cytological examination and the difficulty to obtain tissue biopsies, which are invasive and require procedural skills. Currently, liquid biopsy is increasingly being used for the detection of driver mutations in circulating tumor DNA (ctDNA) from plasma specimens to guide therapeutic interventions. Notably, malignant PF are richer than plasma in tumor-derived products with potential clinical usefulness, such as ctDNA, micro RNAs (miRNAs) and long non-coding RNAs (lncRNAs), and circulating tumor cells (CTC). Tumor-educated cell types, such as platelets and macrophages, have also been added to this diagnostic armamentarium. Herein, we will present an overview of the role of the preceding biomarkers, collectively known as liquid biopsy, in PF samples, as well as the main technical approaches used for their detection and quantitation, including a proper sample processing. Technical limitations of current platforms and future perspectives in the field will also be addressed. Using PF as liquid biopsy shows promise for use in current practice to facilitate the diagnosis and management of metastatic MPE.

Prevalence, clinical characteristics, and outcome of pleural effusions in ovarian cancer.

OBJECTIVES: The prevalence, clinical characteristics and prognosis of pleural effusions (PEs) associated with ovarian cancer (OC) have seldom been addressed systematically, as in the current investigation. METHODS: All records of consecutive women with a newly diagnosed OC in our institution over a 13-year period were retrospectively reviewed. Features of PEs on CT scans, pleural fluid analyses, need for definitive therapy of PEs, and the influence of PEs on the overall survival (OS) and progression-free survival (PFS) were evaluated. RESULTS: PEs were observed in 81 (43%) of 189 women with OC, either at presentation of cancer (55 patients) or during the course of the disease (26 patients). The causes of PEs were malignancy (55.5%), unknown (37%), or surgery-related (7.4%). The sensitivity of the cytologic diagnosis of malignant PEs was 79.1%. Sixty percent of malignant PEs required pleurodesis or indwelling pleural catheters for symptomatic relief. The presence of ascites strongly predicted PE development (odds ratio 43.2). Women with PEs fared much worse compared with those without PEs, in terms of OS (26.7 vs. 90.4 months), PFS (9.8 vs. 55.3 months) and tumor recurrences (86.4 vs. 43%). In multivariate analyses, PE remained as a relevant independent variable associated with poor outcome (hazard ratio 9.73 for OS, and 3.87 for PFS). Notably, PEs small enough to preclude tapping, and thus of unknown origin, had a similar bad prognosis as malignant PEs. CONCLUSIONS: OC patients with PEs experience decreased survival, including those with trace effusions not amenable to tapping.

Clinical Impact of Presurgery Circulating Tumor DNA after Total Neoadjuvant Treatment in Locally Advanced Rectal Cancer: A Biomarker Study from the GEMCAD 1402 Trial.

PURPOSE: Total neoadjuvant treatment (TNT) is a valid strategy for patients with high-risk locally advanced rectal cancer (LARC). Biomarkers of response to TNT are an unmet clinical need. We aimed to determine the value of circulating tumor DNA (ctDNA) to predict tumor response, recurrence, and survival in patients with LARC treated with TNT. EXPERIMENTAL DESIGN: The GEMCAD 1402 was a phase II randomized, multicentric clinical trial that randomized 180 patients with LARC to modified schedule of fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) +/- aflibercept, followed by chemoradiation and surgery. Plasma samples were collected at baseline and after TNT within 48 hours before surgery (presurgery). An ultrasensitive assay that integrates genomic and epigenomic cancer signatures was used to assess ctDNA status. ctDNA results were correlated with variables of local tumor response in the surgery sample, local/systemic recurrence, and survival. RESULTS: A total of 144 paired plasma samples from 72 patients were included. ctDNA was detectable in 83% of patients at baseline and in 15% following TNT (presurgery). No association was found between ctDNA status and pathologic response. Detectable presurgery ctDNA was significantly associated with systemic recurrence, shorter disease-free survival (HR, 4; P = 0.033), and shorter overall survival (HR, 23; P < 0.0001). CONCLUSIONS: In patients with LARC treated with TNT, presurgery ctDNA detected minimal metastatic disease identifying patients at high risk of distant recurrence and death. This study sets the basis for prospective clinical trials that use liquid biopsy to personalize the therapeutic approach following TNT.

Prognostic Factors Involved in the Epithelial-Mesenchymal Transition Process in Colorectal Cancer Have a Preponderant Role in Oxidative Stress: A Systematic Review and Meta-Analysis.

Epithelial-to-mesenchymal transition (EMT) is one of the most accepted mechanisms leading to metastasis, which is responsible for most of the cancer-related deaths. In order to identify EMT-related biomarkers able to predict clinical outcomes in colorectal cancer (CRC), a systematic review and meta-analysis of prognostic factors associated to overall survival (OS) and progression free survival (PFS) was conducted. The systematic literature search included studies from June 2014 to June 2019 available at PubMed and Scopus databases. Meta-analysis was performed for those markers appearing in minimum three works with a total number of 8656 participants. The rest were enlisted and subjected to functional enrichment. We identified nine clinical biomarkers and 73 EMT-related molecular biomarkers associated to OS and/or PFS in CRC. The significant enrichment of biomarkers found involved in cellular oxidoreductase activity suggests that ROS generation plays an active role in the EMT process. Clinical practice needs new biomarkers with a reliable prognostic value able to predict clinical outcomes in CRC. Our integrative work supports the role of oxidative stress in tumorigenesis and EMT progress highlighting the importance of deciphering this specific mechanism to get a better understanding of metastasis.

Association Between Baseline Circulating Tumor Cells, Molecular Tumor Profiling, and Clinical Characteristics in a Large Cohort of Chemo-naïve Metastatic Colorectal Cancer Patients Prospectively Collected.

BACKGROUND: Clinicopathologic characteristics and prognostic and predictive factors offer valuable guidance when selecting optimal first-line treatment in patients with metastatic colorectal cancer (CRC). The association between baseline circulating tumor cell (bCTC) count, molecular tumor profile, and clinicopathologic features was analyzed in a chemo-naïve metastatic CRC population. PATIENTS AND METHODS: A total of 1202 patients from the Spanish VISNÚ-1 (FOLFIRINOX/bevacizumab vs. FOLFOX/bevacizumab) and VISNÚ-2 (FOLFIRI/bevacizumab vs. FOLFIRI/cetuximab; RAS-wildtype) studies were analyzed for mutational status and bCTC count. The association between clinicopathologic characteristics and bCTC count, mutational status, and microsatellite instability (MSI) was analyzed in 589 eligible patients. RESULTS: Interestingly, 41% of the population studied presented ≥3 bCTC count. bCTC count ≥3 was associated with worse performance status (according Eastern Cooperative Oncology Group scale), stage IV at diagnosis, at least 3 metastatic sites, and elevated carcinoembryonic antigen (CEA) levels; but not with RAS or BRAF mutations or high MSI. BRAFmut (BRAF mutated) tumors were associated with right-sided primary tumors, peritoneum, distant lymph node metastasis, and less frequent liver involvement. RASmut (RAS mutated) was associated with worse performance status; stage IV at diagnosis; right-sided primary tumors; liver, lung, and bone metastases; at least 3 metastatic sites; and elevated CEA, whereas PIK3CAmut (PIK3CA mutated) tumors were associated with right-sided primary tumors, high CEA serum levels, and older age. High MSI was associated with right-sided primary tumors, distant lymph nodes metastasis, and lower CEA levels. CONCLUSIONS: In our study, elevated bCTCs and RASmut were associated with clinicopathologic features known to be associated with poor prognosis; whereas the poor prognosis of BRAFmut tumors in chemo-naïve metastatic CRC is not explained by associations with poor clinicopathologic prognostic factors, except right-sided primary tumors. TRIAL REGISTRATION NUMBER: VISNU 1 ClinicalTrials.gov ID: NCT01640405/ VISNU 2 ClinicalTrials.gov ID: NCT01640444.

Predictors of Indwelling Pleural Catheter Removal and Infection: A Single-center Experience With 336 Procedures.

BACKGROUND: Indwelling pleural catheters (IPCs) offer ambulatory management of symptomatic persistent pleural effusions, but their widespread use is somewhat hampered by the risk of pleural infection and the inconvenience of carrying a catheter for a prolonged period of time. Factors associated with these 2 limitations were analyzed in this study. METHODS: Retrospective review of consecutive patients who had undergone IPC placement over a 5 ½-year period. Time to IPC removal was analyzed with the Fine and Gray competing risks survival model, with competing risk being death. A binary logistic regression method was used to evaluate factors influencing IPC-related pleural infections. RESULTS: A total of 336 IPCs were placed in 308 patients, mostly because of malignant effusions (83%). IPC removal secondary to pleurodesis was achieved in 170 (51%) procedures at a median time of 52 days. Higher rates of IPC removal were associated with an Eastern Cooperative Oncology Group (ECOG) grade of 0 to 2 [subhazard ratio (SHR)=2.22], an expandable lung (SHR=1.93), and development of a multiseptated pleural space (SHR=1.37). IPC-related pleural infections occurred in 8% of the cases, and were more often seen in hepatic hydrothoraces [odds ratio (OR)=4.75] and pleural fluids with a C-reactive protein <15 mg/L before the IPC insertion (OR=4.42). CONCLUSION: IPC removal is more likely to occur in patients with good performance status whose lungs fully expand after drainage. Hepatic hydrothorax is the most significant predictor of IPC-related infections.

Effect of Aflibercept Plus Modified FOLFOX6 Induction Chemotherapy Before Standard Chemoradiotherapy and Surgery in Patients With High-Risk Rectal Adenocarcinoma: The GEMCAD 1402 Randomized Clinical Trial.

IMPORTANCE: Preclinical studies suggest that a vascular endothelial growth factor (VEGF) blockade may play a role in the preoperative treatment of rectal adenocarcinoma; however, how to combine anti-VEGF drugs with neoadjuvant chemotherapy (CT) and/or chemoradiotherapy (CRT) remains controversial. OBJECTIVE: To study the effect of aflibercept plus modified fluorouracil, leucovorin, and oxaliplatin (mFOLFOX6) induction CT prior to standard CRT and total mesorectal excision (TME) surgery in patients with high-risk rectal adenocarcinoma. DESIGN, SETTING, AND PARTICIPANTS: In the Grupo Español Multidisciplinar En Cancer Digestivo (GEMCAD) 1402 phase 2 randomized clinical trial, 180 patients aged 18 to 75 years, identified by centrally reviewed magnetic resonance imaging to have mrT3c-d/T4/N2 rectal adenocarcinoma, were enrolled from 20 treatment centers in Spain between January 2015 and March 2017. Patients were randomized in a 2:1 treatment to control arm ratio. The primary end point was evaluated at 2 interim and 1 final analyses. The study was designed to perform hypothesis testing at α = .2 and ß = .2. A 2-sided P value of <.1984 in the final analysis of the intention-to-treat population was the threshold for considering the experimental treatment to be more effective than the control. INTERVENTIONS: Patients received neoadjuvant mFOLFOX6 with (arm A; n = 115) or without (arm B; n = 65) aflibercept, 4 mg/kg (every 2 weeks, 6 cycles, and 3 months) prior to standard CRT and TME surgery. MAIN OUTCOMES AND MEASURES: The primary end point was a pathologic complete response (pCR) (ypT0N0). Secondary end points included toxic effects, surgical morbidity, R0 resections, compliance, and 3-year disease-free survival. RESULTS: For the 115 patients who received treatment with mFOLFOX6 plus aflibercept, the median (range) age was 60 (32-75) years, 77 men (66.9%) and 38 women (33.0%). For the 65 patients who received induction CT treatment with only mFOLFOX6, the median (range) age was 65 (39-75) years, 39 men (60.0%) and 26 women (40.0%). The pCR rate in the intention-to-treat population was 22.6% (95% CI, 15.3%-31.3%) in arm A and 13.8% (95% CI, 6.5%-24.6%) in arm B (P = .15). The main differential toxic effect was grade 3/4 hypertension during the induction phase. Postoperative complications were similar in both arms (15.5% in arm A and 12.9% in arm B). A total of 106 patients (92.1%) in arm A and 63 (96.9%) in arm B received all treatment cycles. CONCLUSIONS AND RELEVANCE: The study met its primary end point. The findings suggest that adding aflibercept to an induction regimen using mFOLFOX6 plays a role in increasing the pCR rate in patients with high-risk rectal adenocarcinoma, without substantially increasing surgical complications. The GEMCAD 1402 trial provides a rationale for phase 3 trials. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02340949.

Epithelial cell adhesion molecule (EpCAM) from pleural fluid cell lysates is a highly accurate diagnostic biomarker of adenocarcinomatous effusions.

BACKGROUND AND OBJECTIVE: The discovery of highly accurate pleural fluid (PF) biomarkers of malignancy remains elusive. We assessed the operating characteristics of the PF epithelial cell adhesion molecule (EpCAM), claudin 4 (CL4) and human epididymis protein 4 (HE4) as potential markers of epithelial malignancies. METHODS: The three markers were quantified by immunoassays in the supernatants (s) and cell lysates (cl) of 175 PF samples. The cut-off values with 100% specificity were selected for malignant-benign discrimination. An immunocytochemical staining index score for each marker was also evaluated on PF cell blocks. The resulting best biomarker was further validated in two independent populations of 73 and 48 patients with pleural effusions (PE). RESULTS: An EpCAM(cl) >98 pg/g total lysate protein yielded 75% sensitivity, 100% specificity, negative likelihood ratio of 0.25 and area under the curve of 0.94 for labelling adenocarcinomatous effusions. Sensitivity reached 88% if EpCAM(cl) was combined with EpCAM immunostaining. One-third or more of the malignant effusions exhibiting a false-negative cytological fluid examination were correctly classified by EpCAM(cl) concentrations. Immunoassays for CL4 and HE4 were diagnostically useless. CONCLUSION: EpCAM(cl) is a new biomarker of adenocarcinomatous PE with meaningful discriminating properties.

Clinical Impact of Circulating Tumor RAS and BRAF Mutation Dynamics in Patients With Metastatic Colorectal Cancer Treated With First-Line Chemotherapy Plus Anti-Epidermal Growth Factor Receptor Therapy.

PURPOSE: RAS and BRAF mutations can be detected as a mechanism of acquired resistance in circulating tumor (ct) DNA in patients with metastatic colorectal cancer treated with anti-epidermal growth factor receptor therapy. METHODS: RAS and BRAF mutational status was assessed in ctDNA in a baseline plasma sample and a serum sample collected at the time of the last available determination (named secondary extraction) from patients with KRAS exon 2 wild-type metastatic colorectal cancer treated in two first-line prospective biomarker-designed clinical trials (PULSE, ClinicalTrials.gov identifier: NCT01288339; and POSIBA, ClincialTrials.gov identifier: NCT01276379). RESULTS: Analysis of extended RAS and BRAF in tissue and plasma from 178 patients with KRAS exon 2 wild-type metastatic colorectal cancer showed a sensitivity of 64.1% and a specificity of 90%. The median overall survival (OS) of baseline patients with RAS and BRAF mutations in ctDNA was 22.3 months (95% CI, 15.6 to 29 months) and 8.9 months (95% CI, 6.3 to 11.4 months), respectively, which was significantly inferior to the median OS of 40.4 months (95% CI, 35.9 to 44.9 months) in two patients with wild-type disease (P < .001). Acquisition of RAS/BRAF mutations occurred in nine of 63 patients (14%) with progressive disease (PD; ie, blood draw within 1 month before PD or after PD) compared with six of 73 patients (8%) with no PD or blood extraction for ctDNA analysis before 1 month of PD (P = .47). Median OS in patients with RAS/BRAF acquisition was 23.9 months (95% CI, 19.7 to 27.9 months) compared with 40.6 months (95% CI, not reached to not reached) in patients who remained free of mutations (P = .016). CONCLUSION: Our results confirm that baseline RAS and BRAF testing in ctDNA discriminates survival. The emergence of RAS/BRAF mutations has limited relevance for the time to progression to anti-epidermal growth factor receptor therapy.

Genomic Profiling of HER2-Positive Gastric Cancer: PI3K/Akt/mTOR Pathway as Predictor of Outcomes in HER2-Positive Advanced Gastric Cancer Treated with Trastuzumab.

BACKGROUND: HER2-positive gastric cancer (GC) affects 7%-34% of patients with GC. Trastuzumab-based first-line treatment has become the standard of care for HER2-positive advanced gastric cancer (AGC). However, there are no clinically validated biomarkers for resistance to HER2-targeted therapies. Upregulation of PI3K pathway and tyrosine kinase receptor (TKR) alterations have been noted as molecular mechanisms of resistance in breast cancer. Our study aimed to perform a molecular characterization of HER2-positive AGC and investigate the role of PI3K/Akt/mTOR signaling pathway activation and TKR gene copy number (GCN) gains as predictive biomarkers in HER2-positive AGC treated with trastuzumab. PATIENTS AND METHODS: Forty-two HER2-positive GC samples from patients treated with trastuzumab-based first-line chemotherapy were selected. DNA samples were sequenced. PTEN and MET immunohistochemistry were also performed. RESULTS: Concurrent genetic alterations were detected in 97.1% of HER2-positive AGC. We found activation of PI3K/Akt/mTOR pathway in 52.4% of patients and TKR GCN gains in 38.1%. TKR GCN gains did not correlate with overall survival (OS) or progression-free survival (PFS). Multivariate Cox models showed that PI3K/Akt/mTOR activation negatively affects the effectiveness of trastuzumab-based chemotherapy in terms of OS and PFS. CONCLUSION: Our results provide for the first time a detailed molecular profile of concurrent genetic alterations in HER2-positive AGC. PI3K pathway activation could be used as a predictive marker of worse outcome in this patient population. In addition, gains in copy number of other TKR genes in this subgroup may also influence the survival benefit obtained with trastuzumab. IMPLICATIONS FOR PRACTICE: This article reports, for the first time, a detailed molecular profile of genomic alterations in patients with HER2-positive advanced gastric cancer (AGC). PI3K/Akt/mTOR signaling pathway activation seems to have a differentially negative effect on overall survival and progression-free survival in AGC treated with trastuzumab-based chemotherapy. Combining different targeted agents could be a successful therapeutic strategy to improve the prognosis of HER2-positive AGC.