bluuebunny/crossref_metadata_2025 huggingface dataset:
Role of sphingosine kinase 1 (SphK1) on cetuximab resistance in colorectal cancer models.
Authors: Bianco Roberto , Rosa Roberta , Nappi Lucia , Formisano Luigi , Damiano Vincenzo , d'Amato Claudia , de Maio Ana Paula , Marciano Roberta , Malapelle Umberto , Troncone Giancarlo , Carlomagno Chiara , De Stefano Alfonso , Tortora Giampaolo , De Placido Sabino
Published: March 2020

e13509

Background: Although EGFR inhibitors, such as the mAb cetuximab, represent an effective strategy in colorectal cancer (CRC), the clinical use of these agents is limited by intrinsic or acquired resistance. Alterations in the ‘sphingolipid rheostat’, or the balance between the proapoptotic molecule ceramide and the mitogenic factor sphingosine-1-phosphate (S1P), due to overactivation of sphingosine kinase 1 (SphK1), have been involved in the regulation of resistance to anticancer agents. Since some studies described cross-talks between SphK1 and EGFR-dependent signalling pathways, we investigated the contribution of SphK1 to cetuximab resistance in CRC models. Methods: We used CRC cell lines with both intrinsic or acquired resistance to cetuximab. In these models, we analyzed SphK1 expression/activation by using different tools, including the available drug fingolimod (FTY720), both in vitro and in vivo. We confirmed our data through a tissue microarray (TMA)-based analysis on CRC tissues. Results: SphK1 is overexpressed in CRC cells resistant to cetuximab. Higher doses of N,N-dimethylsphingosine (DMS), a potent competitive inhibitor of SphK1, are needed to achieve complete enzyme saturation and survival inhibition in resistant cells. Moreover, ceramide induces apoptosis less efficiently in resistant than in sensitive cells, consistently with the idea that increased SphK1 levels mediate S1P synthesis by ceramide in resistant cells. SphK1 contribution to resistance is supported by the demonstration that SphK1 inhibition by DMS or silencing via siRNA in resistant cells restores sensitivity to cetuximab, whereas exogenous SphK1 overexpression in wild-type cells confers resistance. Re-sensitization to cetuximab is observed after treatment with fingolimod, a S1P receptor inhibitor, both in vitro and in nude mice xenografted with CRC cells. Finally, a TMA-based analysis on CRC tissues revealed that SphK1 expression is related to K-Ras mutational status, a well-known determinant of cetuximab resistance. Conclusions: Our data could clarify the role of SphK1 in the onset of resistance to cetuximab, thus suggesting SphK1 inhibition as a part of novel targeting strategies for resistant cancer patients.
Relationship of alterations in the expression of nontargeted genes and suppression of bcl-2 by antisense oligonucleotides.
Authors: Rubenstein Marvin , Hollowell Courtney M.P. , Guinan Patrick
Published: March 2020

e13513

Background: Antisense oligos have been employed against prostate cancer models targeting proteins associated with growth/apoptosis. However gene therapy may not be totally specific. Oligos against bcl-2 are in clinical trials and it was of interest: 1) To see whether therapy produces non-specific effects compromising efficacy; 2) To identify genes whose activity may have to be maintained/replaced. Methods: In LNCaP cells we evaluated monospecific (directed against bcl-2) and bispecific (directed against bcl-2 & epidermal growth factor receptor) oligos which comparably suppressed bcl-2. Cells were evaluated by PCR for expression of non-targeted genes associated with apoptosis (caspase-3, clusterin); androgen regulation (androgen receptor [AR], p300, creb binding protein [CBP]); cytokines (interleukins 2 [IL-2], 4 [IL-4], interferon [IFN]); antigen expression (prostate specific antigen [PSA], prostate membrane antigen [PSMA], prostatic acid phosphatase [PAP]); and autocrine growth (insulin like growth factor [IGF1]). Results: Most non-targeted genes were unaffected. However following suppression of bcl-2 activity by mono- and bispecific oligos, cells compensated by suppressing caspase-3 (apoptosis promoter) and enhancing AR and coactivator p300 expression. This suggests an ability to reverse bcl-2 suppression of apoptosis through decreased expression of a promoter and increased androgen sensitivity. It identifies caspase-3 as an essential gene whose expression must be either maintained/replaced when bcl-2 is therapeutically suppressed. Among the differentiation antigens, cell surface PSMA expression was increased by bispecific oligos; secretory PSA and PAP were not. Increased PSMA may to be due to induced IFN expression produced by bispecific oligos, attributed to a 2X intrastrand conformation not seen in the monospecific oligo. Increased PSMA expression could make prostate cancer cells more recognizable to cytotoxic T cells and potentiate prostate cancer vaccines. Conclusions: If gene therapy is to be effective, the mechanisms for compensatory changes which contribute to tumor resistance must be further identified/controlled.
Cellular response to the combined effect of trifluoperazine and ionizing radiation: A molecular study.
Authors: Gangopadhyay Sudeshna , Karmakar Parimal
Published: March 2020

e13533

Background: It is known that some phenothiazines group of drugs have the potential to modulate ionizing radiation (IR) induced cellular damage. In our previous study, we have shown that Trifluoperazine (TFP), a phenothiazine derivative antipsychotic drug, modulate the effect of IR by inhibiting the IR induced DNA double strand break (DSB) repair, and raising the possibility of using TFP as an adjuvant to radiotherapy. In the present study we tried to explore the mechanism of IR induced DNA damage repair inhibition by TFP. Methods: Effect of TFP and IR on cell viability was determined by MTT assay. Study of possible signaling pathway leading to IR induced cell killing was checked using indirect immunolabeling and transfection. Results: It was observed that the use of TFP (2.5 µg/mL) reduces the LD50 from 13 Gy to 7.5 Gy. After transfecting the cells with GFP-tagged Ku80 plasmid, we have seen that in the gamma-irradiated cells, Ku80 was completely localized in the nucleus, indicating close association of Ku with the broken DNA ends. However, in the TFP (2.5 μg/mL) treated cells, Ku80 was retained in the cytoplasm after irradiation. Similarly, with indirect immunofluorescence experiments using antibody against DNA-PKcs, the catalytic component of DNA-PK, large bright dots of DNA-PKcs was present in the nucleus when cells were treated with IR alone. But, when the cells were irradiated in the presence of TFP, DNA-PKcs migrated to the nucleus partially, even after 4 h of irradiation. Conclusions: Thus, TFP prevents the trafficking of DNA-PK complex from cytoplasm to nucleus and thereby inhibits the DNA-PK mediated NHEJ. Taken together, our results suggest that TFP sequestered the DNA-PK complex, which is a major player in non homologous end joining (NHEJ) and enhance the effect of IR.
Inhibition of cardiomyocytes late INa with ranolazine blunts anthracyclines-cardiotoxicity in experimental models in vitro and in vivo.
Authors: Maurea Nicola , Coppola Carmela , Rea Domenica , Piscopo Giovanna , Riccio Gennaro , Barbieri Antonio , Palma Giuseppe , Gala Marianna , Luciano Antonio , Giudice Aldo , Capasso Immacolata , Scala Stefania , Iaffaioli Rosario Vincenz , De Lorenzo Claudia , Arra Claudio , Tocchetti Carlo G.
Published: March 2020

e13539

Background: Anthracyclines produce a well-known cardiomyopathy through multiple mechanisms, which also include, among many, Ca2+ overload due to reduced SERCA2a activity and inappropriate opening of the RyR2, and impaired myocardial energetics. Anthracyclines generate Reactive Oxigen and Nitrogen Species (ROS and RNS), posing the heart at increased demand for oxygen, thus setting the stage for a metabolic ischemia that also activates late INa, the target of ranolazine (RAN). Here, we aim at assessing whether RAN, diminishing intracellular Ca2+ through its inhibition of late INa, and enhancing myocardial glucose utilization (and/or reverting impairment of glucose utilization caused by chemotherapy) blunts anthracyclines cardiotoxicity. Methods: To assess for toxicity in vitro, rat H9C2 cardiomyoblasts were pretreated with RAN (0.1-1mM) for 72 hours and then treated with doxorubicin (DOX, 0.1 mM) for additional 24 hours. Cells counts were assessed by Trypan exclusion test. To evaluate cardiac function in vivo, fractional shortening (FS) and ejection fraction (EF) were measured by echocardiography in C57BL6 mice, 2-4 mo old, pretreated with RAN (370mg/kg/day, a dose comparable to the one used in humans) per os for 3 days. RAN was then administered for additional 7 days, together with DOX (2.17mg/kg/day ip), according to our well established protocol. Results: After DOX, only 68% of the cells were viable. RAN alone did not affect cell survival, but blunted DOX toxicity, rescuing % cell survival to 87% (p=.01 vs DOX alone). In our in vivo studies, after 7 days with DOX, FS decreased to 50±2%, p=.002 vs 60±1% (sham), and EF to 81±2%, p=0.0001 vs 91±1% (sham). RAN alone did not change FS (59±2%) nor EF (89±1%). Interestingly, in mice treated with RAN and DOX, the reduction in cardiac function was milder: FS was 57±1%, EF was 89±1%, p=0.01 and 0.0009 respectively, vs DOX alone. Conclusions: RAN blunts DOX cardiotoxic effects in 2 different models, in vitro and in vivo. We plan to test RAN as a cardioprotective agent with other antineoplastic cardiotoxic drugs in our experimental models, and to better characterize the cardioprotective mechanisms of RAN in all these settings.
Screening of SirT1 activating compounds and their cytotoxicity in prostate cancer cell lines.
Authors: Fu Maofu , Pattabiraman Nagarajan , Wang Chenguang , Ju Xiaoming , Sauve Anthony , Pestell Richard G.
Published: March 2020

e13545

Background: Our previous studies demonstrated that the human androgen receptor (AR) is an acetylated protein, and acetylation of the AR in the hinge region is essential for its ligand-dependent transactivation. The AR acetylation mimic mutant, ARK630Q, and a somatic mutation from the prostate cancer patient at the AR acetylating motif, ARK630T, showed enhanced receptor/coactivator binding and led to accelerated prostate cancer cell growth. SirT1, an NAD+-dependent class III HDAC, suppresses AR and inhibits prostate cell proliferation via deacetylation of AR. Deletion of the SirT1 gene in mice resulted in prostatic intraepithelial neoplasia (PIN) lesion formation associated with reduced autophagy. Our hypothesis is that small molecules with SirT1 activating properties could be potential novel agents for treatment of AR-expressing prostate cancer. Methods: We performed in-silico screening for small molecule antagonists of SirT1 based on computational model prediction of a known SirT1 activator, resveratrol, and identified potential activators for SirT1. The cytotoxicity of these compounds to the prostate cancer cell lines was tested by MTT assay. Results: Among the twelve compounds tested, three compounds, C5, C6 and C10, were found to inhibit AR expression in LNCaP cells and have cytotoxicity in several prostate cell lines including LNCaP, C4W2 and NeuT-transformed prostate epithelial cell line at concentration of 50 µM. Conclusions: Currently, we are testing the effects of these small molecules on the NAD+-dependent deacetylation activity of SirT1 and their effects on AR acetylation as its molecular mechanism of cell growth inhibition. The ultimate goal of this study is to develop early phase clinical trials in prostate cancer patients by blocking AR acetylation using these SirT1 activators.
A pharmacodynamic study of JI-101, an orally active inhibitor of VEGF-2, PDGF-β, and EphB4 receptors, in patients with refractory/recurrent ovarian cancer.
Authors: Werner Theresa Louise , Luebke Aaron Lynn , Wade Mark , Srinivas Nuggehally R , Abhyankar Dhiraj J. , Caligiuri Philip , Heilbrun Marta Elise , Sharma Sunil
Published: March 2020

e13548

Background: JI-101 is an oral multi-kinase inhibitor, which targets VEGFR-2, PDGF-β, and EphB4. By targeting multiple angiogenesis signaling pathways, JI-101 has the potential advantage of inhibiting all vital stages of tumor angiogenesis, reducing tumor resistance, and enhancing anti-tumor efficacy. None of the currently approved angiogenesis inhibitors have any appreciable inhibition of EphB4, and therefore, this represents a novel mechanism of action. JI-101 has preclinical activity in various tumor models and has been well tolerated in phase 1 trials. Methods: Eleven women with refractory/recurrent ovarian cancer were enrolled with a median age of 54 yrs (range 52-76). All patients had adequate organ function and ECOG performance status ≤ 2. Each patient received single agent JI-101 at 200mg BID for 28 day treatment cycles. Toxicity and response were evaluated at two month intervals. Results: Eight of 11 patients were evaluable for response (3 were unevaluable due to inability to complete two cycles). A median of 3 cycles (range 2-6) was given. No grade 4 adverse events (AEs) were seen. The most common grade 2/3 hematological AEs were grade 2 anemia (1) and lymphopenia (1). The most common grade 2/3 non-hematological AEs were grade 3 hypertension (7), grade 3 bowel obstruction (2), grade 3 transaminitis (2), and abdominal pain (2). Six patients had stable disease (SD) at two months and two had progressive disease. Best response was SD at four months. Two-month progression free survival was 71% (90% CI 52-99%). Conclusions: JI-101 is well tolerated in refractory/recurrent ovarian cancer patients with the majority of patients with stable disease at two months. The most common toxicity was hypertension, which was easily controlled with anti-hypertensives. The novel mechanism of action of JI-101 is promising in ovarian cancer treatment and further prospective studies of this agent could be pursued in a less refractory patient population.
The effect of novel small molecule drugs in human explants across the disease sequence in colorectal cancer.
Authors: Murphy Adrian Gerard , Casey Rory , Fennelly David William , Reynolds Alison , Tosetto Miriam , Hyland John , Sheahan Kieran , O'Donoghue Diarmuid , Mulcahy Hugh , Kennedy Breandan , O'Sullivan Jacintha
Published: March 2020

e13570

Background: The treatment of metastatic colorectal cancer has been improved by combining cytotoxic chemotherapy with bevacizumab. Newer anti-angiogenic agents are required to improve survival rates as response rates with the current therapies are modest. The preclinical development of such drugs is time-consuming and new methods are required to test the efficacy of lead drugs which represent the entire tumor micro-environment. Methods: Chemical screens were performed in zebrafish larvae to identify hits that affected intersegmental angiogenesis. Five lead drugs were then tested for cytotoxicity using the crystal violet assay. These drugs were tested using ex vivo colorectal tumor explants to determine their effect on secretion of IL-1β, TNF, IL-6 and VEGF. Human explants from 20 patients (Dukes A-D) were cultured for 72 hours and the levels of the above factors measured by ELISA. Comparisons were made between early (Dukes A&B) and late stages (Dukes C&D). Results: One thousand drugs were screened and 5 were found to reduce intersegmental angiogenesis in zebrafish larvae: AM1, AM2, AM3, AM4 and AM5. The drugs did not affect cell growth levels at 10 µM concentration. From the explant studies: AM1 decreased secretion of VEGF in late stages (p=0.005) and IL-6 in early stages (p=0.009). AM2 decreased VEGF in early (p=0.004) and late stages (p=0.02). AM3 decreased TNF secretion in late stages (p=0.02) and IL-6 secretion in early (p=0.009) and late stages (p<0.0001). AM4 decreased VEGF secretion in early stages (p=0.001), IL-6 in early stages (p<0.001) and late stages (p=0.03) and IL-1β in early stages (p=0.002). AM5 decreased IL-6 secretion in the early stages (p=0.03) and IL-1β in the early stages (p=0.001).Overall, IL-1β secretion was reduced by AM4, AM3 and AM5 (p<0.05). IL-6 secretion was reduced by AM1, AM3 and AM4 (p=0.001). TNF secretion was reduced by AM3 (p=0.02) and VEGF secretion was reduced by AM1, AM2 and AM4 (p<0.005). Conclusions: These studies show these drugs have stage-specific effects in colorectal tumor explants and may have the potential as new anti-angiogenic agents in colorectal cancer.
Development of a quantitative immunofluorescent method for analysis of nuclear and cytoplasmic p53 and p21 in circulating tumor cells (CTC) as biomarkers of response to p53-targeted therapy.
Authors: Woo Jacky , Wu Weiguo , Melnikova Vladislava O. , Anderes Kenna Lynn , Davis Darren W.
Published: March 2020

e13575

Background: The tumor suppressor p53 is involved in many aspects of cell cycle control and p53 mutations are the most common genetic abnormality in solid tumors. Several diverse approaches targeting p53 signaling including activators of p53, cell cycle checkpoint inhibitors and MdM2 inhibitors are under development and will require determination of p53 status to demonstrate proof of concept and ultimately drive patient selection. Measurement of p53 status in tumor biopsies is often hindered by limited availability of tissues. Detection of p53 status in CTCs offers an alternative to biopsy. Methods: A multiplex immunofluorescent (IF) method for identification of CTCs was developed using cytokeratin, CD45 and DAPI. DO7, a p53 specific antibody, and total and phospho-p21 antibodies were optimized for multiplex detection. Bleomycin (50 mU/mL) was used to activate p53 in A549 p53 wt cells, HT29 and SkBr3 p53 mutant cells. Single cell-based IF analysis was performed pre and post treatment by quantitative Laser Scanning Cytometry (LSC). Results: Wild type A549 cells expressed lower baseline levels of nuclear p53 compared to mutant p53 cell lines HT29 and SKBr3. Total and phosphorylated p21 was also lower in A549 cells compared to HT29 and SKBr3 cells. Bleomycin treatment of wt A549 cells led to a transient increase in p53 expression by 30% while mutant HT29 and SKBr3 cells did not show any change in p53. Treatment of A549 cells with bleomycin led to a 100% increase in total p21and a 70% increase in phosphorylated p21. No change in p21 was observed in p53 mutant HT29 and SKBr3 cell lines. Conclusions: We developed a sensitive, quantitative method for detection of nuclear and cytoplasmic p53 and p21 protein in cell lines that functionally discriminates between p53 wt and p53 mutant status. The method is transferable to circulating tumor cells (CTCs) and may have utility in selecting patients based on functional p53 status and predicting responses to p53 pathway targeted agents.
Preclinical efficacy of the combination of olaparib plus carboplatin with vandetanib in triple-negative breast cancer.
Authors: Dey Nandini , Wu Hui , Sun Yuliang , De Pradip , Leyland-Jones Brian
Published: March 2020

e13579

Background: BRCA1-deficiency confers sensitivity to PARP1 inhibition (alone or in combination with platinum compounds) in triple-negative breast cancer (TNBC). Recent understanding of the biology of TNBC tumor cells has recognized molecular targets suitable for treatment with targeted therapeutics including cell surface RTK(s), such as EGFR. Methods: We studied the effect of combination of PARP inhibitor, (olaparib) plus carboplatin with a dual EGFR/VEGFR inhibitor, vandetanib in a TNBC model in both in vitro and in vivo settings. We tested the effects of drug combinations on (a) cell signaling marker(s) of survival/proliferation/apoptosis, (b) adhesion-dependent and clonogenic survival, and (c) different phenotypes (migration, invasion, vascular mimicry, and cord formation) using TNBC cell and HUVEC cells. The combination of PARP1 inhibition and EGFR/VEGFR inhibition was evaluated in tumor-bearing athymic mice treated with olaparib plus carboplatin and vandetanib. Results: Data showed that, (1) EC50s for vandetanib ranged from 5-15 µM, (2) vandetanib (10 µM) inhibited phosphorylation of AKT (S473 & T308), S6RP, 4EBP1 and ERK, (3) effect of olaparib on TNBC cell survival can be effectively studied in vitro by clonogenic assay, (4) TNBC cell lines exhibited higher sensitivity to vandetanib in clonogenic assay when combined with 10 µM fixed dose of olaparib, and (5) a combination of vandetanib with olaparib plus carboplatin time dependently increased caspase-3 and PARP cleavage, inhibited vascular mimicry, blocked fibronectin-directed migration, and suppressed clonogenic growth in TNBC cells.Vandetanib blocked (a) cord formation, (b) vitronectin-directed migration, and (c) HIF-1alpha accumulation and phosphorylation of proliferation markers (AKT, 4EBP1, and ERK) in HUVEC cells. Conclusions: Anti-proliferative/pro-apoptotic, and anti-migratory/invasive effects of vandetanib (alone or in combination with carboplatin plus olaparib) were observed both in tumor cells and in endothelial cells. We are currently studying in vivo the effect of combining olaparib plus carboplatin with vandetanib, in xenograft model the results of which will be presented in the meeting.
Association of baseline plasma biomarker signature with survival in advanced NSCLC patients on linifanib.
Authors: McKeegan Evelyn Mary , Chakravartty Arunava , Ansell Peter J , Davis Gerard , Chen Gong , Chan Sabrina , Chandran Raj , DeGuzman Angel , Gawel Susan , Dowell Barry , Bhathena Anahita , McKee Mark D. , Ricker Justin L. , Carlson Dawn M. , Devanarayan Viswanath
Published: March 2020

e13583

Background: Linifanib is a potent and selective VEGF and PDGF receptor inhibitor that has activity in unselected, advanced NSCLC patients (pts) both as monotherapy in the relapsed setting and with carboplatin (C) and paclitaxel (P) in the first-line setting. A baseline plasma biomarker signature identifying NSCLC pts most sensitive to linifanib is needed. Methods: An exploratory retrospective analysis of four randomized clinical trials including linifanib or other treatments in relapsed NSCLC was conducted. Evaluable baseline plasma samples were obtained from 116 pts who received linifanib and 71 pts on other treatments. A signature combining established tumor markers (carcinoembryonic antigen [CEA] and fragments of cytokeratin 19 [CYFRA 21-1]) was derived using a sequential BATTing approach. The signature was then tested across a randomized trial of CP + placebo, linifanib 7.5 mg, or linifanib 12.5 mg in first-line advanced, non-squamous NSCLC. Results: In 2/3L NSCLC, the signature was associated with improvement in survival on linifanib monotherapy (HR=0.51 vs. signature negative; P=0.0017), but no improvement in survival on other treatments (P=0.87). In the first-line setting with CP, the signature was associated with significant PFS improvement with linifanib and a trend towards significant overall survival improvement at high dose (Table). Conclusions: A baseline plasma biomarker signature is associated with improved survival in advanced NSCLC patients on linifanib. Incorporation of this signature should be considered in any further investigation of linifanib in NSCLC. [Table: see text]
FOLFIRI-3/bevacizumab induction, then capecitabine/bevacizumab maintenance as front-line strategy for metastatic colorectal cancer: A phase II trial.
Authors: Kim Stefano Chong Hun
Published: March 2020

e14007

Background: Bevacizumab with FOLFIRI or FOLFOX regimen is the standard of care in metastatic colorectal cancer (mCRC). As second line regimen after FOLFOX, FOLFIRI-3 has showed a significantly better PFS in comparison with other irinotecan-based regimen. We therefore evaluated the safety, efficacy and possible predictive factors for FOLFIRI-3 in combination with bevacizumab as initial treatment for mCRC. Secondarily, we evaluated the feasibility of Capecitabine-Bevacizumab maintenance. Methods: We conducted a phase II, multicentric trial of FOLFIRI-3 regimen (irinotecan 100mg/m2 day 1, LV 200mg/m2 day 1, 5-FU bolus 400 mg/m2 day 1 followed by a 36-h 5-FU continuous infusion 2400 mg/m2, irinotecan 100mg/m2 day 3) with bevacizumab (5mg/kg day 1) repeated every 2 weeks, as first-line treatment in mCRC for 6 months, followed by maintenance treatment with bevacizumab (7.5 mg/kg day 1) and capecitabine (1000 mg/m2 day 1 to 14), repeated every 3 weeks. The primary endpoint was objective response rate (ORR). Secondary endpoints were PFS, overall survival (OS), and biologic analysis of potential predictive factors of response to treatment. Results: From October 2007 to July 2009, 61 patients were enrolled for treatment. The ORR was 66.7% (8.3% of complete response and 58.3% of partial response). Stable disease was observed in 25% of patients (disease control rate of 91.7%). PFS was 12 months, and OS was 33 months. Forty patients entered to maintenance phase. Favorable tolerance profile was observed. Median PFS was 14 months, and OS was 36 months. Its efficacy was maintained in patients recently exposed to oxaliplatin. Conclusions: As front-line regimen in mCRC, FOLFIRI3-bevacizumab is maybe the best among irinotecan-5FU-bevacizumab based regimens to obtain objective response rate. PFS and OS are high but it can be secondary to high complete resection rate in our trial. In recently oxaliplatin-exposed patients, FOLFIRI3-bevacizumab regimen should be considered as first line treatment. Capecitabine-bevacizumab maintenance is clearly feasible and its encouraging result should be validated in a large phase III trial.
Different clinical outcome of metastatic colorectal cancer (MCRC) patients treated with intensive triplet chemotherapy plus bevacizumab (FIr-B/FOx) according to KRAS genotype and disease extension.
Authors: Bruera Gemma , Cannita Katia , Di Giacomo Daniela , Lamy Aude , Troncone Giancarlo , Dal Mas Antonella , Coletti Gino , Frébourg Thierry , Sabourin Jean-Christophe , Tosi Mario , Ficorella Corrado , Ricevuto Enrico
Published: March 2020

e14010

Background: Bevacizumab (BEV) plus triplet chemotherapy can increase efficacy of first-line treatment of MCRC, particularly if integrated with secondary liver surgery in liver-limited (L-L) patients (pts). Clinical outcome of FIr-B/FOx regimen was evaluated according to KRAS genotype in L-L and other MCRC pts. Methods: Tumoral and metastatic samples were screened for KRAS codon 12 and 13, and BRAF mutations by SNaPshot and/or direct sequencing. MCRC pts were classified as L-L and other or multiple metastatic (O/MM). Activity and efficacy were evaluated and compared using log-rank test. Results: Fifty-nine pts were evaluated: 31 KRAS wild-type, 53%; 28 KRAS mutant, 47%. At 21.5 months median follow-up, objective response rate (ORR), progression-free survival (PFS) and overall survival (OS) were, respectively: KRAS wild-type 90%, 14 months, 38 months; KRAS mutant 67%, 11 months, 20 months. PFS and OS were, respectively: overall in 25 L-L compared to 32 O/MM evaluable pts, 17 and 12 months, 47 and 21 months, significantly different; in KRAS wild-type, 12 L-L compared to 18 O/MM, 21 and 12 months, 47 and 28 months, significantly different; in KRAS mutant, 13 L-L compared to 14 O/MMS, 11 months equivalently, 39 and 19 months, not significantly different. Conclusions: First line FIr-B/FOx regimen can increase activity and efficacy of KRAS wild-type and mutant MCRC pts; integration with secondary liver surgery significantly discriminates increased clinical outcome in KRAS wild-type L-L compared to O/MM pts while not in KRAS mutant pts.
Safety and efficacy of percutaneous endoscopic gastrostomy tube placement in patients with malignant peritoneal carcinomatosis induced bowel obstruction.
Authors: Vashi Pankaj G , Braun Donald Peter , Popiel Brenten , Gupta Digant
Published: March 2020

e14012

Background: Percutaneous Endoscopic Gastrostomy (PEG) tube placement in advanced peritoneal carcinomatosis with bowel obstruction is a feasible palliative procedure to help patients with obstructive symptoms. We describe the safety and efficacy of using PEG tube for decompression in patients with large peritoneal masses. Methods: A consecutive case series of 62 patients (Apr-08 to Jun-11) with advanced abdominal carcinomatosis induced bowel obstruction. All patients were extensively treated for their cancer. None of them were surgical candidates due to extensive peritoneal involvement. All patients had symptoms of nausea, vomiting and pain at the time of PEG tube placement. All patients had a 28F (Bard) PEG tube placed for drainage. The primary outcomes of interest were complications and symptom resolution due to PEG tube placement. Frequency of nausea, vomiting and severity of pain was recorded daily in patient charts. Results: 16 were males and 46 females. The mean age was 50.5 years. Most common cancers were ovary, pancreas, colon and stomach. Of 62 patients, 57 patients had expired at the time of this analysis. Of those 57 expired, 49 had PEG tube at the time of death, while 8 had complete resolution of symptoms with PEG tube removed before death. The 5 out of 62 patients who are alive still have the PEG tube for drainage (average 70.4 days). The average duration of PEG tube placement for all patients combined was 70.9 days (range 6-312 days). Relief of nausea, vomiting and pain was observed in 53 (85.5%), 55 (88.7%) and 35 (56.5%) patients respectively. Of a total of 43 patients who had PEG tube placed for >= 30 days, 24 (56%) could continue with their chemotherapy cycles because of symptom resolution. Non life threatening complications of PEG tube placement were observed in 9 (14.5%) patients. 3 had infection at the insertion site, 2 had bleeding and 3 had leaking at the PEG tube site while 1 had aspiration. 6 (9.7%) patients required replacement of the PEG tube due to occlusion. Conclusions: Placement of PEG tube in presence of advanced peritoneal carcinomatosis is safe and effective in relieving obstructive symptoms as well as extending the period of active cancer therapy.
Effect of major liver resection on colon cancer metastasis in the lung and liver.
Authors: Hoffman Robert M. , Momiyama Masashi , Suetsugu Atsushi , Kishimoto Hiroyuki , Chishima Takashi , Bouvet Michael , Endo Itaru
Published: March 2020

e14014

Background: Liver resection is a common procedure in liver-metastatic colon cancer. However, recurrence is common and distant liver metastasis may be appear after liver resection. Methods: Experimental liver metastases were established by spleen injection of the Colon 26 murine colon cancer cell line expressing green fluorescent protein (GFP) into transgenic nude mice expressing red fluorescent protein (RFP). Experimental liver metastases was established by splenic injection of Colon-26-GFP. Experimental lung metastases were established by tail vein injection with Colon 26-GFP. Three days after cell injection into the spleen or tail vein, groups of mice underwent liver resection (35%+35% [repeated minor resection] vs. 70% [major resection]). Metastatic tumor growth was measured by color-coded fluorescence imaging of the GFP-expressing cancer cells and RFP-expressing stroma. Results: Although major and repeated minor resection removed the same volume of liver parenchyma, the two procedures had very different effects on metastatic tumor growth. Major resection, stimulated liver and lung metastatic growth as well as recruitment of host-derived stroma into the metastases compared to repeated minor resection. Repeated minor resection did not stimulate metastasis or stromal recruitment. There was no significant difference in liver regeneration between the two groups. TGF-β was also preferentially stimulated by major resection. Conclusions: Host-derived stroma density, which is stimulated by major resection compared to repeated minor resection, may stimulate metastatic growth. Stromal growth may be stimulated by TGF-β. The results of this study indicate that caution should be taken when planning a major liver resection for metastatic colorectal cancer. Conservative resections that spare liver parenchyma should be considered whenever possible.
The kinetics of the excision repair cross-complementing group-1 (ERCC1) gene in patients with colorectal cancer.
Authors: Merla Amartej , Mallick Atrayee Basu , Augustine Titto A , Chaudhary Imran , Gajavelli Srikanth , Maitra Radhashree , Daroqui Cecilia , Aparo Santiago , Seetharam Raviraja , Rajdev Lakshmi , Kaubisch Andreas , Madajewicz Stephan , Negassa Abdissa , Mariadason John , Ghalib Mohammad Haroon , Goel Sanjay
Published: March 2020

e14019

Background: Oxaliplatin is an integral drug in the management of patients with colorectal cancer (CRC); however, half the patients fail to benefit from it. We know that in vitro, the excision repair cross-complementing group-1 (ERCC1) gene is inducible and contributes to cellular resistance to oxaliplatin. Using peripheral blood mononuclear cells (PBMC) as a surrogate tissue, we sought to confirm in vivo, the inducibility of ERCC gene expression and its relationship to clinical outcomes. Methods: Patients with CRC who received oxaliplatin consented to blood (PBMC) sampling at 0, 2, 48 hours, and 14 days during any cycle of chemotherapy. Clinical benefit from oxaliplatin was determined using the parameters of response rate and progression free and overall survival (PFS and OS). ERCC1 gene expression was quantified by qPCR (quantitative real time polymerase chain reaction) and WB (western blotting). Results: A total of 52 patients have been enrolled of which 29 patients have sampling at all 4 time points. ERCC1 gene expression was induced in 48.5% and 66.7% by mRNA and WB, respectively. Down regulation was observed in 30.3% and 8.3% by mRNA and WB, respectively. No change was noted in rest of the patients. The median PFS in patients with ERCC1 induction by qPCR was 7.25 months and was numerically shorter than the 13 months noted in patients with stable or reduced ERCC. This may suggest that in patients with ERCC induction, there is compromised PFS, but our data is limited by the small sample size. The difference in induction noted between qPCR and WB remains unclear. We did not find any significant difference in PFS when taking baseline expression of ERCC into consideration. Conclusions: This study confirms the inducibility of ERCC gene expression in vivo, in a sub-population of patients with CRC when they are treated with oxaliplatin. This gene induction is a potential marker of resistance to chemotherapy. We failed to find an association between clinical benefit and baseline ERCC expression. The factors that influence the inducibility of this gene remain unknown requiring further studies.
Adjuvant chemotherapy containing oxaliplatin without radiotherapy to improve survival of local advanced low and middle rectal cancer.
Authors: Ding Ke-Feng , Li Jun , Song Yong-Mao , Wang Jian-Wei , Yuan Ying , Zhang Suzhan
Published: March 2020

e14024

Background: In this study, the impact of oxaliplatin on survival of local advanced rectal cancer patients were analyzed by comparing the survival of patients accepted only radical surgery (group S) and patients accepted radical surgery following oxaliplatin-containing adjuvant chemotherapy (group SO). Methods: The data of patients, who accepted radical surgery in our center from Jan 2002 to Jun 2009, were reviewed. Inclusion criteria: carcinoma ≤12 cm from the anal verge; pathologically confirmed T3/4 or N1/2; without history of malignancy; neither transanal nor transsacral resection. Patients who accepted radiotherapy were excluded. The disease specific survival (DSS) and overall survival (OS) of patients in group S and SO were analyzed. Results: 236 patients were included in analysis (S 135 vs. SO 101), including 11 patients without survival information. The most of patients' basic characteristics were similar in two groups (P>0.05). However, the ratio of stage II patients in group S was higher than that in group SO (51.9% vs. 27.0%, P<0.001). The DSS of group SO were higher in patients with stage II, N1a or mucious adenocarcinoma than patients in group S (P<0.05). The OS of group SO were higher in patients with N1a, N2 or mucious adenocarcinoma than patients in group S (P<0.05). Conclusions: Adjuvant chemotherapy containing oxaliplatin improved survival of local advanced low and middle rectal cancer. Randomized perspective trials are needed to clarify the importance of oxaliplatin for rectal cancer. [Table: see text]
Prediction of lymph node metastasis and prognosis in colorectal cancer patients using slug and vimentin expression.
Authors: Toiyama Yuji , Yasuda Hiromi , Saigusa Susumu , Okugawa Yoshinaga , Tanaka Koji , Inoue Yasuhiro , Uchida Keiichi , Mohri Yasuhiko , Tabata Tsutomu , Goel Ajay , Kusunoki Masato
Published: March 2020

e14029

Background: Slug plays a critical role in regulating the epithelial-mesenchymal transition (EMT) by down-regulation of epithelial markers and up-regulation of mesenchymal markers. The purpose of the present study was to evaluate the clinical significance of Slug and Vimentin expression in colorectal cancer (CRC) and to perform in vitro characterization of Slug’s function. Methods: At first, the biological role of Slug in CRC was assessed by RNA interference in CRC cell lines to assess tumor progression, invasion and migration. We next analyzed Slug and Vimentin expression in surgical tissue specimens from 181 CRC patients by quantitative reverse transcriptase polymerase chain reaction and immunohistochemistry. Results: Knockdown of Slug in siRNA knockdown studies resulted in induction of EMT markers, inhibited cancer cell proliferation, invasion and migration abilities. Slug and Vimentin expression in cancer tissues was significantly higher in patients with high T stage, lymph node involvement, liver metastasis and advanced TNM stage. We also observed a significant correlation between Slug and Vimentin expression in CRC (rho = 0.467). Increased Slug and Vimentin expression were significantly associated with poor prognosis in Stage I-IV (p<0.0001, p=0.0005, log-rank test) and Stage II (p= 0.04, p=0.012, log-rank test) Furthermore, increased Slug expression was an independent predictive marker of lymph node metastasis (p=0.012) and prognostic factor (p= 0.025). Conclusions: Our data demonstrate that evaluation of Slug and Vimentin could be valuable in the identification of patients with lymph node metastasis or poor prognosis in CRC.
Treatment patterns and site of metastasis in patients with metastatic colorectal cancer (mCRC).
Authors: Iqbal Sheikh Usman , Thompson Stephen F , Naoshy Sarah , Ng Daniel B , Wooten Michael , Sherman Steven A , Malangone Elisabetta , Stern Lee , Gorritz-Kindu Magdaliz
Published: March 2020

e14030

Background: The real-world impact of metastatic (met) site on Tx choice in mCRC is unknown. Therapeutic associations across metastases can identify gaps in care and inform clinical decision support systems. This study assessed Tx patterns in mCRC pts by met site. Methods: 4656 stage III/IV pts ≥18 yrs at mCRC diagnosis receiving anticancer agents were followed in a retrospective observational study using electronic medical records from the largest oncology database (SDI) from 1/1/04-7/31/11. 1st- (1L), 2nd- (2L), and 3rd-line (3L) therapies were identified for top 4 met sites. Logistic regression adjusting for met site overlap determined Tx use by met site and therapy line. Results: Pts were mostly male (54.1%) and on average 61.6 yrs. The top 4 met sites were liver (34.2%), lung (15.9%), lymph (15.8%), and bone (7.5%). Leading regimens are presented in the table below. Bevacizumab (B) use varied by met site and therapy line. Against other/unknown met sites, 1L B was more common in liver (OR=2.06 [1.75-2.42]) and bone (OR=1.46 [1.16-1.84]), less common in lymph (OR=0.60 [0.50-0.73]), and statistically equal in lung (OR=1.01 [0.85-1.20]). In 2L, B was more likely to be given for liver (OR=1.77 [1.48-2.11]) and lung (OR=1.45 [1.21-1.74]) vs no significant difference for bone (OR=1.17 [0.92-1.50]) and lymph (OR=0.87 [0.71-1.07]) sites. B use in 3L mirrored 2L. Conclusions: Besides 1L in pts with lymph metastases, top regimens across met sites for 1L, 2L, and 3L were FX + B, FR + B, and IRI + C, respectively; however, significant differences in B Tx patterns were evident. Further research should examine the impact of differential B use on outcomes. [Table: see text]
Association of genetic variants in plastin family genes with tumor recurrence in stage II/III colon cancer.
Authors: Ning Yan , Winder Thomas , Zhang Wu , Yang Dongyun , Loupakis Fotios , Wakatsuki Takeru , Bohanes Pierre Oliver , EI-Khoueiry Rita , Barzi Afsaneh , Iqbal Syma , EI-Khoueiry Anthony , Lenz Heinz-Josef
Published: March 2020

e14031

Background: Plastins belong to a subclass of actin-binding proteins known as actin bundling proteins. Plastins family constitute of two isoforms in human as T-plastin (PLS3) and L-plastin (LCP1). Recent in vitro and in vivo studies found plastin genes are overexpressed in colon cancer cells and can lead to increased proliferation, invasion and metastasis. Here we tested the hypothesis whether potential functional tagging polymorphisms in PLS3 (rs6643869, rs5987947, rs2522188) and LCP1 (rs4941543, rs1409429, rs11342) may predict tumor recurrence in adjuvant colon cancer patients. Methods: Either blood or FFPE tissue specimens were obtained from 234 patients (107 females and 127 males; median age 59 years (range 22–78 years)) with stage II (105 patients) or III (129 patients) colon cancer at the University of Southern California/Norris Comprehensive Cancer Center. The median follow-up was 4.4 years. PLS3 and LCP1 SNPs were determined by PCR-RFLP or PCR-based direct sequence. The primary endpoint of the study was time to tumor recurrence (TTR). Results: In univariable analysis, PLS3 rs6643869 and LCP1 rs4941543 were significantly associated with time to tumor recurrence (TTR). Patients with PLS3 AA genotype had shortest median TTR 3.2 years (95% C.I: 1.5-10.7) compared to those with AG or GG genotype, which had median TTR 9.4 years (95% C.I: 5.7-12.2) (p=0.012, log-rank test). Patients with LCP1 CC genotype had longer median TTR 10.7 years (95% C.I: 5.7-16.8+) compared to those with CT and TT genotypes, which had shorter median TTR 4.9 years (95% C.I: 1.4-9.0+)(p=0.040, log-rank test). PLS3 rs6643869 remained significant in the multivariate Cox regression model adjusted by stage and type of adjuvant therapy and stratified by race (p=0.021). Conclusions: Our preliminary results demonstrated that polymorphisms in plastin family genes PLS3 and LCP1 might be potential molecular markers to predict TTR in adjuvant colon cancer. Further large and biomarker embedded trial needed to confirm our findings.
Standardization for lymphatic mapping in breast, melanoma, and GI cancers: An international survey.
Authors: Kanaan Mohammed Nawaf , Kitagawa Yuko , Zuber Markus , Manyam Madhavi , Gafford Philip , Wiese David , Beutler Thomas , Arora Madan L. , Takeuchi Hiroya , Saha Sukamal
Published: March 2020

e14045

Background: The technique of SLNM varies between surgeons, hospitals, and countries in terms of type and amount of dye, pathologic examination of SLN, technical issues of dye injection. The purpose of this study is to evaluate the methods of lymphatic mapping in solid tumors around the world to create a form of international reference for all surgeons to use in patients with breast, melanoma, and GI cancers. Methods: A web-based survey form was created with 12 questions in regards to various aspects of SLNM, for melanoma, breast, esophagus, stomach, colon and rectal cancers. This questionnaire was distributed to 425 centers in the U.S, 60 in Europe, and 60 in Japan. Results: Of the 545 centers surveyed, 122 centers (22.4 %) responded. Of these, 47 were from U.S, 60 from Japan, and 15 from Europe. The order of frequency of the organ sites for lymphatic mapping were: Breast, melanoma, stomach, colon, esophagus, and rectum. There were 56 centers that perform SLNM in one organ site (most common breast), 39 on 2 organ sites, and 14 centers on 3 organ sites. Radiocolloid was the most common mapping agent used 80%. Most common blue dyes were Lymphazurin/Isosulfan in U.S, Patent Blue in Europe and Indocyanine Green in Japan. For breast , the most common site of injection was subareolar, while in upper GI submucosal, and in lower G.I it was subserosal. Overall the average volume of injection for mapping was 1-2 ml (range 0.4-5 ml). Pathological intraoperative interpretation varied from 74% in breast, 38% in melanoma, and 42% in upper G.I and 26% in lower G.I. Conclusions: Although a pattern of continuity emerged through this survey in regards to mapping techniques, there were significant variances between centers and organ sites.Thus, the need for standardization in lymphatic mapping for solid tumors to act as a reference point for future oncologists to follow. [Table: see text]
Tumor size as a prognostic factor for colon cancer patients undergoing sentinel lymph node mapping and conventional surgery.
Authors: Saha Sukamal , Kanaan Mohammed Nawaf , Mozayen Mohammad , Gafford Philip , Shaik Mohammed Saifullah , Johnston Gregory , Tesfaye Anteneh A. , Nagpal Sunil , Kaushal Sunil , Wiese David
Published: March 2020

e14046

Background: Unlike other solid tumors, tumor size (TS) is not a part of the TNM staging system for colon cancer. Our goal is to correlate TS with TNM staging, nodal positivity (NP), and 5-year overall survival (OS) for patients (pts) with invasive colon cancer undergoing sentinel lymph node mapping (SLNM) vs. conventional surgery (CS). Methods: A retrospective review of 681 pts with invasive adenocarcinoma of the colon were reviewed and divided into two groups of pts (SLNM and CS). These groups were subdivided according to the size of the tumor in four groups (0-2, 2-4, 4-6 and more than 6 cm). 461 pts underwent SLNM between 1996-2010 compared to 220 pts who underwent CS between 1996-2006. The pathology reports reviewed for TS (the maximum diameter of the primary tumor), T staging, and NP. The OS was calculated from the social security database. Then all data was compared between both groups. Results: Pts with tumors <2cm were mainly T1+T2 (72%, 70%), whereas tumors >6 cm, majority of pts wereT3+T4 (94%, 85%). T1+T2 percentage consistently decreased as TS increased, and T3+T4 percentage was increasing consistently with increased TS (Table 1A). NP according to TS for SLNM pts were (16%, 53%, 56%, 48%) NP and for CS pts were (15%, 32%, 34%, 39%). In both groups, NP increased as TS increased compared to 0-2 cm group. The overall NP in both groups was 47% and 31% (Table 1B). OS for SLNM and CS pts were calculated in each group according to TS. Overall SLNM pts had better OS when compared to CS pts (65 %, 54%). Conclusions: Increasing TS was consistent with increasing T staging for both SLNM and CS pts. NP and OS were worse with increased TS for SLNM and CS pts. SLNM pts had higher NP and better outcome in OS when compared to CS pts, hence TS should be considered as a prognostic factor in pts with adenocarcinoma of the colon. [Table: see text] [Table: see text]