Antonia Kalykaki

Phosphorylated EGFR and PI3K/Akt signaling kinases are expressed in circulating tumor cells of breast cancer patients

IntroductionThe phosphoinositide-3 kinase (PI3K)/Akt pathway, operating downstream of epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor (HER)2, is implicated in cell migration and survival. EGFR and HER2 are expressed in circulating tumor cells, but the activation status of downstream signaling molecules has not yet been reported.MethodsTo investigate expression levels of EGFR, HER2, PI3K, and Akt in circulating tumor cells, we used peripheral blood mononuclear cells from 32 cytokeratin-19 mRNA-positive patients with early (n = 16) and metastatic (n = 16) breast cancer.Peripheral blood mononuclear cell cytospins were double stained with cytokeratin antibody along with one of the following: EGFR, phospho-EGFR, HER2, phospho-PI3K, or phospho-Akt antibodies.ResultsEGFR and HER2 were expressed in circulating tumor cells of 38% and 50% patients with early and 44% and 63% patients with metastatic disease, respectively. Interestingly, phospho-PI3K and phospho-Akt expression levels were similar at 88% (14 out of 16) and 81% (13 out of 16), respectively, in circulating tumor cells of patients with early and metastatic disease. Phospho-EGFR was observed in circulating tumor cells of two (33%) early and six (86%) metastatic EGFR-positive patients. Immunomagnetic separation of peripheral blood mononuclear cells, using EpCAM antibody, and subsequent double-staining experiments of circulating tumor cells showed that EGFR was co-expressed with HER2, phospho-Akt and phospho-PI3K kinases, indicating activation of the corresponding survival signaling pathway.ConclusionsOur findings demonstrate that circulating tumor cells express receptors and activated signaling kinases of the EGFR/HER2/PI3K/Akt pathway, which could be used as targets for their effective elimination.

Front-line bevacizumab in combination with oxaliplatin, leucovorin and 5-fluorouracil (FOLFOX) in patients with metastatic colorectal cancer: a multicenter phase II study.

PurposeTo evaluate the efficacy and the toxicity of front line FOLFOX4 combined with bevacizumab in patients with metastatsic CRC (mCRC).Patients and MethodsChemotherapy-naïve patients with mCRC, received bevacizumab (5 mg/kg every 2 weeks d1), oxaliplatin (85 mg/m2 on d1), leucovorin (200 mg/m2) on days 1 and 2 and 5-Fluorouracil (400 mg/m2 as i.v. bolus and 600 mg/m2 as 22 h i.v. continuous infusion on days 1 and 2) every 2 weeks.ResultsFifty three patients (46 with a PS 0–1) were enrolled. Complete and partial response was achieved in eight (15.1%) and 28 (52.8%) patients, respectively (ORR: 67.9%; 95% C.I.: 53.8%–92%); 11 (20.7%) patients had stable disease and six (11.3%) progressive disease. With a median follow up period of 13.5 months, time to tumor progression was 11 months while the median survival has not yet been reached; the probability of 1-, 2- and 3- year survival was 79.8%, 63.8% and 58.3%, respectively; Two patients relapsed during the follow up period. Eight (15%) patients underwent metastasectomy with R0 resections. Grade 3–4 neutropenia occurred in 15.1% of patients and one (1.9%) of them presented febrile neutropenia. Non-hematologic toxicity included grade 3 diarrhea (7.6%) and grade 2 and 3 neurotoxicity in 16.9 and 15.1% of patients, respectively. One (1.9%) patient presented pulmonary embolism and one (1.9%) cardiac ischaemia. There was one (1.9%) sudden death after the first cycle.ConclusionThe combination of FOLFOX4/bevacizumab appears to be highly effective, well tolerated and merits further evaluation in patients with mCRC.

Cytokeratin-19 mRNA-positive circulating tumor cells during follow-up of patients with operable breast cancer: prognostic relevance for late relapse

BackgroundThe detection of cytokeratin-19 (CK-19) mRNA-positive circulating tumor cells (CTC) before and/or after adjuvant chemotherapy in patients with operable breast cancer is associated with poor clinical outcome. Reliable prognostic markers for late disease relapse are not available. In this study we investigated the value of CTC detection during the first five years of follow-up in predicting late disease relapse.MethodsBlood was analyzed from 312 women with operable breast cancer who had not experienced disease relapse during the first two years of follow-up. A real-time reverse transcriptase polymerase chain reaction (RT-PCR) for CK-19 mRNA was used to detect CTC three months after the completion of adjuvant chemotherapy and every six months thereafter for a follow-up period of five years.ResultsEighty patients (25.6% of the study population) remained CTC free throughout the five-year period. A change in CTC status was observed in 133 patients (42.6%); 64 patients (20.5%) with initially CK-19 mRNA-positive CTC during the first 24 months turned CTC-negative afterwards while 69 (22.1%) who were initially CTC-negative became CTC-positive. Ninety-nine patients (31.7%) remained persistently CK-19 mRNA-positive. After a median follow-up period of 107 months (range: 38 to 161 months), the persistently CTC-positive patients with either hormonal receptor positive or negative tumors, had a higher risk of late-disease relapse compared to the persistently CTC-negative patients (36.4% versus 11.2%, P <0.001). Multivariate analysis revealed that persistently CTC-positive patients also had a shorter disease-free (P = 0.001) and overall survival (P = 0.001).ConclusionsPersistent detection of CK-19 mRNA-positive CTC during the first five years of follow-up is associated with an increased risk of late relapse and death in patients with operable breast cancer and indicates the presence of chemo-and hormonotherapy-resistant residual disease. This prognostic evaluation may be useful when deciding on subsequent adjuvant systemic therapy.

Chemotherapy-induced neutropenia as a prognostic factor in patients with advanced non-small cell lung cancer treated with front-line docetaxel—gemcitabine chemotherapy

BACKGROUND Front-line docetaxel-gemcitabine (DG) combination represents an alternative to platinum-based chemotherapy in patients with advanced NSCLC. One of its more common side effects is neutropenia. The association between the grade of DG-induced neutropenia and the clinical outcome was analyzed. PATIENTS AND METHODS Eight hundred fifty-eight patients with locally advanced/metastatic NSCLC, treated with front-line DG were retrospectively analyzed. Patients were categorized into three groups according to the presented worst neutropenia grade: absent (grade 0), mild (grades I/II) and severe (grades III/IV). RESULTS Response rate, median time to tumor progression (TTP) and median overall survival (OS) were significantly better in patients developing any grade of neutropenia compared with those without neutropenia. The median TTPs were 3.0, 5.4 and 5.6 months for the groups with absent, mild and severe neutropenia, respectively; the median OSs were 7.9, 12.5 and 11.2 months for the same groups, respectively. Multivariate analysis revealed that both mild and severe chemotherapy-induced neutropenia were independent factors associated with a better TTP and OS survival. CONCLUSION Although DG-induced neutropenia was emerged as an independent prognostic factor, it remains to be demonstrated in prospective studies that dose escalation of chemotherapy drugs in patients who do not develop neutropenia may improve the clinical efficacy.

Efficacy of Lapatinib in Therapy-Resistant HER2-Positive Circulating Tumor Cells in Metastatic Breast Cancer

Background To evaluate the efficacy of lapatinib, a dual EGFR and HER2 tyrosine kinase inhibitor, in therapy-resistant HER2-positive CTCs in metastatic breast cancer (MBC). Patients and Methods Patients with MBC and HER2-positive CTCs despite disease stabilization or response to prior therapy, received lapatinib 1500 mg daily in monthly cycles, till disease progression or CTC increase. CTC monitoring was performed by immunofluorescent microscopy using cytospins of peripheral blood mononuclear cells (PBMCs) double stained for HER2 or EGFR and cytokeratin. Results A total of 120 cycles were administered in 22 patients; median age was 62.5 years, 15 (68.2%) patients were post-menopausal and 20 (90.1%) had HER2-negative primary tumors. At the end of the second course, HER2-positive CTC counts decreased in 76.2% of patients; the median number of HER2-positive CTCs/patient also declined significantly (p = 0.013), however the decrease was significant only among patients presenting disease stabilization (p = 0.018) but not among those with disease progression during lapatinib treatment. No objective responses were observed. All CTC-positive patients harbored EGFR-positive CTCs on progression compared to 62.5% at baseline (p = 0.054). The ratio of EGFR-positive CTCs/total CTCs detected in all patients increased from 17.1% at baseline to 37.6% on progression, whereas the mean percentage of HER2-negative CTCs/patient increased from 2.4% to 30.6% (p = 0.03). Conclusions The above results indicate that lapatinib is effective in decreasing HER2-positive CTCs in patients with MBC irrespectively of the HER2 status of the primary tumor and imply the feasibility of monitoring the molecular changes on CTCs during treatment with targeted agents. Trial Registration Clinical trial.gov NCT00694252

A multicenter phase II trial with irinotecan plus oxaliplatin as first-line treatment for inoperable/metastatic cancer of the biliary tract.

Purpose: To evaluate the efficacy and tolerability of oxaliplatin (L-OHP) in combination with irinotecan (CPT-11) as first-line treatment of advanced biliary tract cancer. Patients and Methods: Patients with histologically confirmed nonresectable biliary adenocarcinoma were treated with oxaliplatin (85 mg/m2) and irinotecan (200 mg/m2) every 3 weeks.Results: Twenty-eight patients were enrolled between May 2005 and March 2009. The overall objective response rate was 17.9% with an additional 21.4% of patients with stable disease (disease control rate 39.3%). The median overall survival time was 9.2 months (95% CI 5.8–12.5) and the median progression-free survival time 2.7 months (95% CI 2.2–3.2). Grades 3 and 4 neutropenia occurred in 1 (3.6%) and 4 (14.3%) patients, respectively, and febrile neutropenia in 3 (10.7%). Grade 3–4 diarrhea was observed in 2 (7.1%) patients and grade 3 asthenia in 1 (6%). There were no treatment-related deaths. Conclusion: The combination of oxaliplatin and irinotecan has a modest antitumor activity with manageable toxicity as first-line treatment in metastatic cancer of the biliary tract and therefore it cannot be recommended as front-line treatment for unresectable biliary tract cancer.

A dose escalation study of gemcitabine plus pemetrexed administered biweekly in patients with solid tumors.

Purpose: The study aimed to determine the maximum tolerated doses (MTDs) and identify the dose-limiting toxicities of the biweekly administration of pemetrexed plus gemcitabine in patients with solid tumors. Patients and Methods: Patients with advanced malignancies were treated with escalated doses of gemcitabine and pemetrexed (starting doses 1,250 and 300 mg/m2, respectively) both given on days 1 and 15 in cycles of 4 weeks. Results: Forty-one patients were treated at 7 dose levels. The MTD was reached at the dose of 1,750 mg/m2 for gemcitabine and 450 mg/m2 for pemetrexed. Dose-limiting events were grade IV neutropenia, febrile neutropenia and treatment delay due to grade III hematological toxicities. One partial response in a pretreated patient with ovarian cancer was observed, while 4 other patients experienced stable disease. Conclusions: The biweekly administration of gemcitabine plus pemetrexed at the recommended MTDs is safe, well tolerated and demonstrates antitumor activity which merits further evaluation in phase II studies.

A dose escalation study of the biweekly administration of paclitaxel, oxaliplatin and capecitabine in patients with advanced solid tumors

Purpose: To determine the dose-limiting toxicities (DLTs) and the maximum-tolerated doses of the paclitaxel, oxaliplatin (LOHP) and capecitabine combination in patients with advanced solid tumors. Patients and Methods: Patients received escalating doses of paclitaxel (starting dose 100 mg/m2) and LOHP (starting dose 40 mg/m2) on days 1 and 15 and capecitabine (starting dose 800 mg/m2/day) on days 1–7 and 15–21 every 28 days. DLTs were evaluated in the first cycle. Results: Sixteen patients were treated at four dose-escalating levels. Eleven (68.7%) patients had received two or more prior chemotherapy regimens. The DLT level was reached at paclitaxel 110 mg/m2, LOHP 50 mg/m2 and capecitabine 1,000 mg/m2/day. DLTs due to grade 2–3 neutropenia resulted in treatment delays. No febrile neutropenia or treatment-related death occurred. Grade 2–3 neutropenia occurred in 3 (19%) patients each, grade 2–4 fatigue affected 6 (37.5%) patients, and grade 2–3 neurotoxicity was observed in 2 (12.5%) and 1 (6%) patients, respectively. Two partial responses and four disease stabilizations were achieved. Conclusion: The recommended doses for phase II studies are paclitaxel 100 mg/m2 and LOHP 50 mg/m2 on days 1 and 15 and capecitabine 1,000 mg/m2/day on days 1–7 and 15–21 every 4 weeks. This regimen is well tolerated and merits further evaluation.

Abstract 3411: A pilot feasibility study to evaluate the efficacy of lapatinib in the elimination of HER2-positive circulating tumor cells in peripheral blood of women with metastatic breast cancer

Proceedings: AACR 103rd Annual Meeting 2012‐‐ Mar 31‐Apr 4, 2012; Chicago, IL Background: The monitoring of circulating tumor cells (CTCs) detected in peripheral blood (PB) of patients (pts) with metastatic breast cancer (BC) has been proven a potent prognostic tool. CTCs detected after the completion of therapy are theoretically chemo- and/or hormone-resistant and could lead to disease progression. EGFR and HER2 expression has been demonstrated in CTCs from pts with BC. In the present trial we aimed to evaluate the efficacy of lapatinib, a dual EGFR and HER2 tyrosine kinase inhibitor, in eliminating HER2 positive (+) CTCs of women with metastatic BC. Pts and methods: Pts with metastatic BC and HER2+ CTCs detected despite disease stabilization or response after the completion of prior therapy were eligible. Pts received lapatinib, 1500 mg/day orally till disease or CTC progression, whichever occurred first. HER2 expression was evaluated in cytospins of peripheral blood mononuclear cells’ (PBMCs) prepared from PB obtained at baseline and monthly thereafter. Cytospins were stained with HER2 along with cytokeratin antibody; a total of 10^6 PBMCs/pt were analyzed by double immunofluorescence. Results: Nineteen pts were enrolled from September 2008 to October 2011. Median age was 62 years, 12 (63.2%) pts were post-menopausal and 2 had HER2+ tumors. Twelve (63.2%) pts had visceral disease and 7 (36.8%) had received β3 lines of treatment. One pt discontinued treatment prior to the completion of the first cycle due to toxicity and 2 pts are not evaluable yet. The median duration of treatment was 4.0 (range, 0.5 - 34.0) months (mo). CTC counts declined in 15 out of 16 pts during treatment with a maximum percentage of decrease of 100% in all of them. The median time to and the median duration of nadir CTC counts were 1 mo (range, 1 - 3 mo) and 1 mo (range, 0 - 7 mo), respectively. Prior to the second treatment cycle, a decrease in CTC counts was observed in 14 (88%) pts, in 1 (7%) the CTC count increased by 33% and in 1 (7%) remained stable. Median percentage of CTC count decrease per pt was 100% (range, 45-100%). At baseline, a total of 2642 HER2+ CTCs were detected (median: 79/pt, range 2 - 617), whereas after the completion of first cycle a total of 430 HER2+ CTCs were identified (median: 0, range 0 - 223). Disease evaluation revealed stable disease in 5 pts and progressive disease in 11. In pts with stable disease a sustained decrease in CTC counts over 2 to 7 mo was observed. On the contrary, in 9 out of 11 pts with disease progression, the decrease in CTC counts was short-lasting (median 1.0 mo, range 0 - 4). Conclusions: Lapatinib is effective in decreasing HER2+ CTCs in pts with metastatic BC, irrespective of the HER2 status of the primary tumor. Sustained CTC reduction was associated with disease stabilization. The above results suggest that tailoring therapy according to targets present on CTCs could be an effective therapeutic strategy in BC. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3411. doi:1538-7445.AM2012-3411