Circulating programmed death ligand-1 (cPD-L1) in non-small-cell lung cancer (NSCLC)

Background

This study aimed at investigating feasibility of programmed death ligand-1 (PD-L1) testing in plasma samples of advanced NSCLC patients receiving first-line treatment, assessing whether circulating (c)PD-L1 levels were modified by the therapy and whether baseline cPD-L1 levels were associated with patients’ clinical responses and survival outcome.

Methods

Peripheral blood samples were collected from 16 healthy volunteers and 56 newly diagnosed NSCLC patients before and at 12th week during the course of first-line therapy. The level of PD-L1 was measured in plasma samples using the human (PD-L1/CD274) ELISA kit (CUSABIO, MD, USA). The Mann Whitney test or Fisher’s test were used for comparisons. Survival analysis was performed using Kaplan Meyer method, providing median and p-value.

Results

Baseline median cPD-L1 was 42.21 pg/ml (range 12.00-143.49) in NSCLC patients and 37.81 pg/ml (range 9.73-90.21) in healthy control cohort (p = 0.78). Median cPD-L1 increased in patients treated with first-line chemotherapy (63.20 pg/ml vs 39.34 pg/ml; p = 0.002), with no changes in patients exposed to non-chemotherapy drugs (42.39 pg/ml vs 50.67 pg/ml; p = 0.398). Time to progression and overall survival were 4.4 vs 6.9 months (p = 0.062) and 8.8 vs 9.3 months (p = 0.216) in cPD-L1 positive vs cPD-L1 negative patients. Baseline cPD-L1 levels increased with the ascending number of metastatic sites, even if the association was not statistically significant (p = 0.063).

Conclusions

This study showed that cPD-L1 testing is feasible, with chemotherapy influencing PD-L1 plasma levels. The possibility of using such test for predicting or monitoring the effect of immunotherapy or combination of chemotherapy and immunotherapy warrant further investigations.

Contribution of KRAS mutations and c.2369C > T (p.T790M) EGFR to acquired resistance to EGFR-TKIs in EGFR mutant NSCLC: a study on circulating tumor DNA

INTRODUCTION

KRAS oncogene mutations (MUTKRAS) drive resistance to EGFR inhibition by providing alternative signaling as demonstrated in colo-rectal cancer. In non-small cell lung cancer (NSCLC), the efficacy of treatment with EGFR tyrosine kinase inhibitors (EGFR-TKIs) depends on activating EGFR mutations (MUTEGFR). However, inhibition of EGFR may select resistant cells displaying alternative signaling, i.e., KRAS, or restoration of EGFR activity due to additional MUTEGFR, i.e., the c.2369C > T (p.T790MEGFR).

AIM

The aim of this study was to investigate the appearance of MUTKRAS during EGFR-TKI treatment and their contribution to drug resistance.

METHODS

This study used cell-free circulating tumor DNA (cftDNA) to evaluate the appearance of codon 12 MUTKRAS and p.T790MEGFR mutations in 33 advanced NSCLC patients progressing after an EGFR-TKI.

RESULTS

p.T790MEGFR was detected in 11 (33.3%) patients, MUTKRAS at codon 12 in 3 (9.1%) while both p.T790MEGFR and MUTKRAS codon 12 were found in 13 (39.4%) patients. Six patients (18.2%) were KRAS wild-type (WTKRAS) and negative for p.T790MEGFR. In 8 subjects paired tumor re-biopsy/plasma samples were available; the percent concordance of tissue/plasma was 62.5% for p.T790MEGFR and 37.5% for MUTKRAS. The analysis of time to progression (TTP) and overall survival (OS) in WTKRAS vs. MUTKRAS were not statistically different, even if there was a better survival with WTKRAS vs. MUTKRAS, i.e., TTP 14.4 vs. 11.4 months (p = 0.97) and OS 40.2 vs. 35.0 months (p = 0.56), respectively.

CONCLUSIONS

MUTKRAS could be an additional mechanism of escape from EGFR-TKI inhibition and cftDNA is a feasible approach to monitor the molecular development of drug resistance.

Immune checkpoint therapy of mesothelioma: Pre-clinical bases and clinical evidences

Treatment with immune-checkpoint blocking monoclonal antibody (mAb) is demonstrating a significant efficacy in different tumor types. Here, we discuss the impact of this promising approach in malignant mesothelioma (MM), a still dreadful disease in which medical treatment has been set on platinum based chemotherapy for decades with unsatisfactory results.

Abstract 4853: NRP2b, a unique isoform of NRP2, promotes aggressive lung cancer phenotypes

Neuropilins (NRPs) 1 and 2 are highly-related receptors for class 3 semaphorins, and interact with heparin-binding growth factors and their receptors (e.g. HGF-MET, VEGF-VEGFR2 etc.). We previously reported that NRP2 is upregulated by TGFβ and is required for its pro-tumorigenic activity. Here, we show that this upregulation preferentially involves NRP2b, a largely uninvestigated isoform encoding a divergent, yet highly-conserved C-terminus. Importantly, using a panel of lung cancer cell lines and orthotopic metastasis model, NRP2b promoted migration, invasion, metastasis and tumorsphere formation, whereas the prototype receptor, NRP2a had opposite effects. TGFβ-mediated resistance to gefitinib in EGFR mutated tumors also was dependent on NRP2b expression. In addition, NRP2b, but not NRP2a, linked MET activation by HGF to AKT phosphorylation. Mechanistically, in co-immunoprecipitation assays, we found that NRP2a robustly interacted with PTEN, while the interaction with NRP2b was weak. At the clinical level, NRP2b expression was commonly upregulated in patient lung cancer samples and this upregulation was a significant poor-prognostic factor. Collectively, these data indicate that NRP2b plays an important role in lung cancer invasion, metastasis and EGFR inhibitor resistance. Furthermore, isoform-specific interactions between NRP2 and PTEN may be responsible for the observed differences in MET signaling in response to HGF.

Citation Format: Anastasios Dimou, Patrick Nasarre, Joyce Nair-Menon, Federico Cappuzzo, Lorenza Landi, Armida D'Incecco, Hidetaka Uramato, Takeshi Yoshida, Eric Haura, Monica Gooz, Kent Armeson, Robert Gemmill, Harry Drabkin. NRP2b, a unique isoform of NRP2, promotes aggressive lung cancer phenotypes [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4853. doi:10.1158/1538-7445.AM2017-4853

Tremelimumab in combination with durvalumab in first or second-line mesothelioma patients: Safety analysis from the phase II NIBIT-MESO-1 study

8558

Background: The anti-CTLA-4 tremelimumab at two different dose-schedules of administration showed promising activity in second-line malignant mesothelioma (MM) patients (Calabrò et al., Lancet Oncol, 2013; Calabrò et al., Lancet Respir Med, 2015). These initial results and the efficacy of targeting the PD-1/PD-L1 axis in different tumor types, prompted the NIBIT-MESO-1 study aimed at investigating the efficacy and safety of tremelimumab combined with the anti-PD-L1 durvalumab in mm patients. We report the safety analysis from the fully-enrolled NIBIT-MESO-1 study. Methods: The NIBIT-MESO-1 is a phase II, open-label, single Center study. Forty mm patients received tremelimumab at 1 mg/Kg i.v. every 4 weeks (Q4W) for 4 doses, and durvalumab at 20 mg/Kg i.v. Q4W for 13 doses. Primary objective is immune-related (ir)-objective response rate; secondary are safey, ir-disease control rate, ir-progression free survival, and overall survival. Tumor assessment per ir-modified RECIST or ir-RECIST 1.1 for pleural or peritoneal MM, respectively, was performed at baseline and q12 weeks. Adverse events (AEs) were recorded according to CTC v4.0. (ClinicalTrials.gov Id: NCT02588131). Results: From October 2015 to October 2016, 40 mm patients (38 pleural and 2 peritoneal), median age 64 years (range 41-80), ECOG performance status 0 (n = 19) or 1 (n = 21) were enrolled in the study. mm histology was epithelioid (n = 32), biphasic (n = 5), sarcomatoid (n = 2) or undefined (n = 1). As of January 2017, 12 first or 28 second-line mm patients received a median of 5.5 doses of therapy (range = 1-13). Twenty-four patients (60%) experienced any grade irAEs: 5 patients (12.5%) had grade 3-4 AEs, the most frequent being hepatotoxicity (7.5%). AEs were generally manageable and reversible per protocol guidelines. Three patients (7.5%) were discontinued due to treatment-related AEs (1 trombocytopenia, 1 limbic encephalitis, 1 liver toxicity). Conclusions: The combination of tremelimumab and durvalumab is safe and manageable in mm patients. Clinical trial information: NCT02588131.

The neuropilin 2 isoform NRP2b uniquely supports TGFβ-mediated progression in lung cancer

Neuropilins (NRP1 and NRP2) are co-receptors for heparin-binding growth factors and class 3 semaphorins. Different isoforms of NRP1 and NRP2 are produced by alternative splicing. We found that in non-small cell lung cancer (NSCLC) cell lines, transforming growth factor-β (TGFβ) signaling preferentially increased the abundance of NRP2b. NRP2b and NRP2a differ only in their carboxyl-terminal regions. Although the presence of NRP2b inhibited cultured cell proliferation and primary tumor growth, NRP2b enhanced cellular migration, invasion into Matrigel, and tumorsphere formation in cultured cells in response to TGFβ signaling and promoted metastasis in xenograft mouse models. These effects of overexpressed NRP2b contrast with the effects of overexpressed NRP2a. Hepatocyte growth factor (HGF)-induced phosphorylation of the kinase AKT was specifically promoted by NRP2b, whereas inhibiting the HGF receptor MET attenuated NRP2b-dependent cell migration. Unlike NRP2a, NRP2b did not bind the PDZ domain scaffolding protein GAIP carboxyl terminus-interacting protein (GIPC1) and only weakly recruited phosphatase and tensin homolog (PTEN), potentially explaining the difference between NRP2b-mediated and NRP2a-mediated effects. Analysis of NSCLC patient tumors showed that NRP2b abundance correlated with that of the immune cell checkpoint receptor ligand PD-L1 as well as with epithelial-to-mesenchymal transition (EMT) phenotypes in the tumors, acquired resistance to epidermal growth factor receptor (EGFR) inhibitors, disease progression, and poor survival in patients. NRP2b knockdown attenuated the acquisition of resistance to the EGFR inhibitor gefitinib in cultured NSCLC cells. Thus, in NSCLC, NRP2b contributed to the oncogenic response to TGFβ and correlated with tumor progression in patients.

Cytochrome P450 1B1 (CYP1B1) polymorphisms are associated with clinical outcome of docetaxel in non-small cell lung cancer (NSCLC) patients

PURPOSE

Cytochrome P450 1B1 (CYP1B1) is involved in the metabolism of anticancer agents; its overexpression was associated with resistance to docetaxel, a commonly used drug for second-line treatment of NSCLC. Several functional single nucleotide polymorphisms (SNPs) have been associated with CYP1B1 expression and activity. The objective of this study was to retrospectively evaluate the correlation of CYP1B1 SNPs with the outcome of NSCLC patients treated with docetaxel in second or third line.

METHODS

Associations between CYP1B1 4326C>G and 4390A>G polymorphisms with response, progression-free survival (PFS) and overall survival (OS) were estimated using Pearson χ(2) test, Kaplan-Meier curves and log-rank test; a multivariate analysis was performed using Cox proportional hazards modeling.

RESULTS

A total of 65 advanced NSCLC patients were enrolled into the analysis. Median age was 66 years (range 46-81). Forty-nine patients were male; only five were never smokers. Performance status (PS) was 0 in 25 patients, 1 in 28 and 2 in 12. Histology was adenocarcinoma in 28 patients, squamous carcinoma in 22, other NSCLC in the remaining 15. At univariate analysis, stage and CYP1B1 4326C>G SNPs are associated with PFS, while PS and CYP1B1 4326C>G SNPs correlated with OS. In particular, patients with CYP1B1 4326-GG genotype had shorter PFS and OS than patients with other genotypes (PFS 1.80 vs. 2.70 months, p = 0.12; OS 3.63 vs. 9.83 months, p = 0.039). CYP1B1 4326C>G SNPs were also associated with response rate. Multivariate analysis confirmed the independent prognostic/predictive role of CYP1B1 4326C>G SNPs on OS (p = 0.042) with only a trend for PFS (p = 0.083).

CONCLUSIONS

CYP1B1 4326C>G polymorphism emerged as possible prognostic/predictive marker of activity and efficacy of docetaxel in NSCLC patients.

PD-1 and PD-L1 expression in molecularly selected non-small-cell lung cancer patients

BACKGROUND

Agents targeting programmed death-1 receptor (PD-1) and its ligand (PD-L1) are showing promising results in non-small-cell lung cancer (NSCLC). It is unknown whether PD-1/PD-L1 are differently expressed in oncogene-addicted NSCLC.

METHODS

We analysed a cohort of 125 NSCLC patients, including 56 EGFR mutated, 29 KRAS mutated, 10 ALK translocated and 30 EGFR/KRAS/ALK wild type. PD-L1 and PD-1 expression were assessed by immunohistochemistry. All cases with moderate or strong staining (2+/3+) in >5% of tumour cells were considered as positive.

RESULTS

PD-1 positive (+) was significantly associated with current smoking status (P=0.02) and with the presence of KRAS mutations (P=0.006), whereas PD-L1+ was significantly associated to adenocarcinoma histology (P=0.005) and with presence of EGFR mutations (P=0.001). In patients treated with EGFR tyrosine kinase inhibitors (N=95), sensitivity to gefitinib or erlotinib was higher in PD-L1+ vs PD-L1 negative in terms of the response rate (RR: P=0.01) time to progression (TTP: P<0.0001) and survival (OS: P=0.09), with no difference in PD1+ vs PD-1 negative. In the subset of 54 EGFR mutated patients, TTP was significantly longer in PD-L1+ than in PD-L1 negative (P=0.01).

CONCLUSIONS

PD-1 and PD-L1 are differentially expressed in oncogene-addicted NSCLC supporting further investigation of specific checkpoint inhibitors in combination with targeted therapies.

EGFR and K-Ras mutations in women with lung adenocarcinoma: implications for treatment strategy definition

Background

We aimed at investigating the outcomes of female patients with stage IIIB-IV adenocarcinoma of the lung according to EGFR and K-Ras mutational status.

Methods

One hundred and three consecutive female patients genotyped at a single Italian Institution were analyzed. Patients were planned to receive first-line platinum-based chemotherapy (CT) and a salvage treatment with anti-EGFR tyrosine-kinase inhibitors (TKIs) was proposed irrespective of tumor mutational status. EGFR (exons 18–21) and K-Ras (exon 2, codons 12–13) mutations were evaluated by real-time PCR and pyrosequencing. The association of mutational status with clinical variables and treatment benefit was investigated by chi-square test and log-rank test.

Results

EGFR and K-Ras mutations were found in 31 (30%) and 13 (15%) cases, respectively. Sixty-six patients received platinum CT: no correlation was observed between EGFR or K-Ras mutational status and response rate (RR) (p > 0.05). However, patients treated with first-line CT harboring EGFR activating mutations experienced a significantly reduced progression-free survival (PFS) in comparison with wild-type ones (4.4 vs. 6.4 months, respectively; HR 0.597, 95% CI 0.287-0.975; p = 0.048). Thirty-nine patients received salvage treatment with erlotinib: EGFR activating mutations were significantly correlated with RR (60% vs. 12.5%; p = 0.004) and PFS (11.4 vs. 4.5 months; HR 0.491, 95% CI 0.216-0.936; p = 0.044). Responses to erlotinib were not reported among women with K-Ras mutant tumors, while 50% of those with wild-type K-Ras achieved an objective remission (p = 0.296). Median PFS (3.5 vs. 8.8 months; HR 0.284, 95% CI 0.015-0.510; p = 0.010) and OS (3.9 vs. 19.8 months; HR 0.158, 95% CI 0.001-0.075; p < 0.001) were significantly shorter among K-Ras mutant patients treated with TKI.

Conclusions

In our population of Caucasian women with advanced lung adenocarcinoma we observed that the presence of EGFR activating mutations correlates with a significant reduction in the benefit from first-line platinum-based CT, emphasizing the importance of an upfront use of anti-EGFR TKIs in this patient subset. K-Ras mutations seem to correlate with a detrimental effect from anti-EGFR TKI, but this finding deserves further investigation.

Activity of the EGFR-HER2 dual inhibitor afatinib in EGFR-mutant lung cancer patients with acquired resistance to reversible EGFR tyrosine kinase inhibitors

BACKGROUND

The purpose of this study was to evaluate the efficacy of afatinib in EGFR-mutant metastatic NSCLC patients with acquired resistance to erlotinib or gefitinib.

MATERIALS AND METHODS

We retrospectively analyzed the outcome of patients with EGFR-mutant advanced NSCLC treated with afatinib after failure of chemotherapy and EGFR TKIs.

RESULTS

A total of 96 individuals were included in the study. According to EGFR status, most patients (n = 63; 65.6%) harbored a deletion in exon 19, and de novo T790M mutation was detected in 2 cases (T790M and exon 19). Twenty-four (25%) patients underwent repeated biopsy immediately before starting afatinib and secondary T790M was detected in 8 (33%) samples. Among the 86 patients evaluable for efficacy, response rate was 11.6%, with a median progression free-survival (PFS) and overall survival (OS) of 3.9 and 7.3 months, respectively. No significant difference in PFS and OS was observed according to type of last therapy received before afatinib, type of EGFR mutation or adherence to Jackman criteria, and patients benefiting from afatinib therapy had longer PFS and OS (P < .001). Outcome results for repeated biopsy patients were similar to the whole population, with no evidence of response in T790M-positive patients. All patients were evaluable for toxicity, and 81% experienced an AE of any grade, with grade 3 to 4 AEs, mainly diarrhea and skin toxicity, occurring in 19 (20%) patients.

CONCLUSION

Our results showed that afatinib has only modest efficacy in a real life population of EGFR mutant NSCLC patients with acquired resistance to erlotinib or gefitinib.

Protein kinase inhibitors to treat non-small-cell lung cancer

INTRODUCTION

Activating mutations of the EGFR and rearrangement of anaplastic lymphoma kinase (ALK) best illustrate the therapeutic relevance of molecular characterization in NSCLC patients.

AREAS COVERED

For this review article, all published data on the most relevant Phase III trials with tyrosine kinase inhibitors (TKIs) for the treatment of NSCLC were collected and analyzed.

EXPERT OPINION

Eight Phase III trials clearly established EGFR TKIs as the best therapeutic option for front-line therapy in EGFR-mutated patients. In pretreated NSCLC, EGFR TKIs are considered more effective than standard monotherapy with cytotoxics in presence of classical EGFR mutations, whereas in the EGFR wild-type population, a similar efficacy to docetaxel or pemetrexed in term of survival has been demonstrated. In ALK-translocated NSCLC, a Phase III trial demonstrated the superiority of a multi-target TKI, including ALK, in terms of progression-free survival, response rate and toxicity profile when compared to standard second-line chemotherapy. New agents targeting EGFR or ALK are under evaluation particularly in individuals with acquired resistance to EGFR TKIs or crizotinib.

MicroRNA signature in metastatic colorectal cancer patients treated with anti-EGFR monoclonal antibodies

BACKGROUND

To investigate whether microRNAs are predictive of sensitivity to anti-epidermal growth factor receptor (EGFR) monoclonal antibodies in patients with metastatic colorectal cancer (mCRC).

METHODS

A total of 183 mCRC cases from 2 independent cohorts (cohort 1: 74 cases; validation cohort: 109 cases) treated with cetuximab or panitumumab were included in the study. MiRNA arrays were analyzed using Agilent's miRNA platform.

RESULTS

The study identified the cluster Let-7c/miR-99a/miR-125b as a signature associated with an outcome different from that of anti-EGFR therapies. In the first cohort, patients with high-intensity signatures had a significantly longer progression-free survival (PFS) (6.1 vs. 2.3 mo; P = .02) and longer overall survival (OS) ( 29.8 vs. 7.0 mo, P = .08) than patients with low-intensity signatures. In the validation cohort, patients with high signature had significantly longer PFS and OS than individuals with low-intensity signatures (PFS 7.8 vs. 4.3 mo, P = .02; OS 12.8 vs. 7.5 mo, P = .02). In the KRAS wild-type population (n = 120), high-intensity signature patients had a significantly longer PFS (7.8 vs. 4.6 mo, P = .016) and longer OS (16.1 vs. 10.9 mo, P = .09) than low-signature individuals, with no difference in KRAS mutated patients.

CONCLUSION

The MiR-99a/Let-7c/miR-125b signature may improve the selection of patients with KRAS wild-type mCRC as good candidates for anti-EGFR therapy.

Rare mutations in non-small-cell lung cancer

In the last decade, new insights in molecular biology have changed the therapeutic landscape of non-small-cell lung cancer. Since 2004, when activating mutations of the EGFR were firstly identified, several genetic aberrations have been discovered, mainly in adenocarcinoma. EGFR mutations are a relatively frequent event in non-small-cell lung cancer, generally consisting of exon 19 deletion or exon 21 substitution. In adenocarcinoma, additional rare mutations are detectable in the EGFR gene, as well as in other genes, including ALK, ROS1, RET, HER2 and BRAF. Recent studies in squamous cell carcinoma identified TP53 as the most frequent mutation, followed by additional more rare mutations, including PI3KCA, PTEN, DDR2 and FGFR. The aim of the present review is to analyze the potential prognostic and predictive role of rare mutations.

Targeted therapy for NSCLC with driver mutations

INTRODUCTION

Activating mutations of the epidermal growth factor receptor (EGFR) gene and rearrangement of anaplastic lymphoma kinase (ALK) gene best illustrate the therapeutic relevance of molecular characterization in non-small cell lung cancer (NSCLC) patients. Several genetic aberrations with a potential prognostic or predictive role have been identified, mainly in adenocarcinoma subtype, including ROS1, RET, MET, HER2, BRAF and KRAS. More recently oncogenic drivers, such as DDR2, FGFR1 and PI3KCA, have been characterized in squamous cell lung carcinoma (SCC) and target agents are currently under evaluation. The aim of this review is to summarize the growing scenario of new targetable oncogenes in NSCLC.

AREAS COVERED

For this review article all published data on NSCLC genomic alterations, including the techniques employed for oncogenic drivers identification, the prevalence of each one in lung cancer subtypes, the preclinical data corroborating their role in tumorigenesis and the potential biological tailored agents tested and under evaluation were collected and analyzed using PubMed.

EXPERT OPINION

Oncogenic products represent reliable targets for drug therapy and the expanding knowledge of molecular pathways involved in lung tumorigenesis is resulting in a dramatic change of treatment strategies leading to an improvement in disease and symptom control, extending life duration and improving quality of life.

Let-7g and miR-21 expression in non-small cell lung cancer: correlation with clinicopathological and molecular features

MicroRNAs (miRNAs) play a key role in cancer pathogenesis and are involved in several human cancers, including non-small cell lung cancer (NSCLC). This study evaluated Let-7g and miR-21 expression by quantitative real-time PCR in 80 NSCLC patients and correlated the results with their main clinicopathological and molecular features. MiR-21 expression was significantly higher in NSCLC tissues compared to non-cancer lung tissues (p<0.0001), while no significant changes in Let-7g expression were observed between the tumor and normal lung tissues. Target prediction analysis led to the identification of 26 miR-21 and 24 Let-7g putative target genes that play important roles in cancer pathogenesis and progression. No significant association was observed between the analysed miRNAs and the main clinicopathological or molecular characteristics of the NSCLC patients, although both miRNAs were downregulated in squamous cell carcinomas compared to adenocarcinomas. Noteworthy, we observed a significant association between low Let-7g expression and metastatic lymph nodes at diagnosis (p=0.046), as well as between high miR-21 expression and K-Ras mutations (p=0.0003). Survival analysis did not show any significant correlation between prognosis and the analysed miRNAs, although the patients with a high Let-7g and miR-21 expression showed a significantly lower short-term progression-free survival (p=0.01 and p=0.0003, respectively) and overall survival (p=0.023 and p=0.0045, respectively). In conclusion, we showed that Let-7g and miR-21 expression was deregulated in NSCLC and we demonstrated a strong relationship between miR-21 overexpression and K-Ras mutations. Our data indicate that Let-7g and miR-21 profiling combined with the determination of K-Ras mutational status may be considered a useful biomarker for a more effective molecular characterization and clinical management of NSCLC patients.

Micro-RNA signature differences in lung adenocarcinoma with specific driver alterations

11066

Background: Oncogenic driving alterations define types of lung adenocarcinoma with different prognosis and sensitivity to targeted agents. MicroRNAs (miRNAs) are a new class of non-coding RNAs involved in gene expression regulation. How miRNAs are dysregulated in lung cancer with ALK translocation, EGFR or KRAS mutation is unknown. In this study we aimed to identify miRNA signatures according to the presence of specific driver and to correlate miRNAs deregulation with patient outcome. Methods: The study was conducted in a cohort of 70 lung cancer patients (pts) including 18 ALK+ tumors, 11 ALK-/EGFR mutation+, 15 ALK-/KRAS mutation+, 26 ALK-/EGFR and KRAS wild-type and defined as triple negative. Matched normal lung tissue from 18 cases representative of the entire cohort were also included onto the analysis. RNA was isolated from formalin-fixed paraffin-embedded tissue (FFPE), using the Recover ALL kit (Ambion). NanoString nCounter system platform was used to generate the miRNA profile. We used Limma to test for differential expression analysis of data. The miR-515 family expression between tissues was validated by RT-qPCRs, analyzed using the parametric t-test (unpaired, 2-tailed for validation). Results: miRNA expression profile clusters distinctly ALK+ pts from ALK- and normal lung tissue. Within the ALK- group we found specific miRNAs subsets able to sub-stratify KRAS versus EGFR careers clustering sharply triple negative versus EGFR mutation+ and triple negative versus KRAS mutation+. miRNAs belonging to the miR-515 family seems to be the most deregulated in the ALK+ versus ALK-. Although their expression is stably high in normal tissues and ALK+ class, they are highly downregulated in KRAS mutated versus EGFR mutated and versus triple negative (p-value <0.001 for all comparisons). Conclusions: miRNAs profile significantly differs in pts with ALK translocation, EGFR mutations and KRAS mutations. Analysis of miR-515 family members is ongoing in order to correlate their expression levels with pts’ outcome. In vitro modulation of miR-515 family expression levels, together with drugs treatment are ongoing in order to find possible chemo-resistance/chemo-sensitivity miRNA dependent, in ALK+ and ALK- model.

Abstract 3061: Micro-RNA signature differences in lung cancer patients with ALK translocation, EGFR mutations and KRAS mutations

Background: Oncogenic driving mutations identify lung adenocarcinoma with different prognosis and sensitivity to targeted therapies. miRNAs are a new class of non-coding RNA involved in gene expression regulation and recent studies have suggested that miRNAs could be useful for stratifying lung cancer subtypes. How miRNAs are dysregulated in lung cancer patients with ALK translocation, EGFR or KRAS mutation is unknown. Aim of the present study is to identify miRNA signature differences according to the presence of specific oncogenic driver and correlation between miRNAs deregulation and drug response.

Materials and methods: The study was conducted in a cohort of 70 lung cancer patients including 68 primary cancer tissue (17 ALK positive tumors, 11 ALK negative EGFR positive tumors, 15 ALK negative KRAS positive tumors, 24 ALK negative EGFR and KRAS negative tumors defined as wild-type) with matched normal lung tissue (N=18) and 2 metastatic tissue. RNA was isolated from formalin-fixed paraffin-embedded tissue (FFPE), using the Recover ALL kit (Ambion). Data were processed according to manufacture guidelines. We used Limma to test for differential expression analysis of data. The miRNAs expression between tissues for all RT-qPCR was analyzed using the parametric t-test (unpaired, 2-tailed for validation).

Results: miRNA expression profile, cluster distinctly ALK+ patients from ALK- and normal lung tissue. Furthermore we found specific miRNAs subsets, within the ALK- group, able to sub-stratify KRAS versus EGFR careers and cluster sharply wild-type versus EGFR and wild-type versus KRAS as well. miRNAs belonging to the miR-515 family seems to be the most deregulated in the ALK+ vs ALK- comparison. Although their expression is stably high in normal tissues and ALK+ class they are highly downregulated in KRAS mutated versus EGFR mutated and versus ALK-/KRAS wild type/EGFR wild type (p-value &lt;0.001 for all comparisons).

Conclusions: miRNAs profile significantly differs in lung cancer patients with ALK translocation, EGFR mutations and KRAS mutations. Molecular analysis of the pathways involving the miR-515 family is ongoing in order to correlate their expression levels with patients’ outcome. Since miRNAs can induce resistance or sensitize to chemotherapies, in vitro modulation of miR-515 family expression level together with drugs test are ongoing in order to find better targeted therapies for ALK+ and ALK- patients.

Citation Format: Pierluigi Gasparini, Lorenza Landi, Stefania Carasi, Carmelo Tibaldi, Luciano Cascione, Greta Alì, Armida D'Incecco, Gabriele Minuti, Antonio Chella, Gabriella Fontanini, Federico Cappuzzo, Carlo M. Croce. Micro-RNA signature differences in lung cancer patients with ALK translocation, EGFR mutations and KRAS mutations. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3061. doi:10.1158/1538-7445.AM2013-3061

Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.

MYC gene copy number (GCN) and sensitivity to anti-EGFR monoclonal antibodies in metastatic colorectal cancer (mCRC)

e21018

Background: Monoclonal antibodies against Epidermal Growth Factor Receptor (EGFR) demonstrated efficacy in mCRC patients without mutations in the KRAS gene. Previous data in breast and lung cancer suggested that MYC GCN affects sensitivity to anti-EGFR agents. Methods: This retrospective study was conducted in a cohort of 303 mCRC patients treated with cetuximab/panitumumab, either alone (N=24) or in combination with chemotherapy (N=279). MYC GCN was assessed by fluorescence in situ hybridization (FISH) in primary colorectal cancer tissue samples. Results: In the study population response rate (RR) was 28%, median progression-free survival (PFS) 5.6 months and median overall survival (OS) 11.8 months. MYC was successfully evaluated in 298 cases and was amplified in 17 patients (5.7%). Individuals with MYC amplification showed a trend for a lower RR (7.7% versus 28.9%, p=0.12), shorter PFS (3.0 months versus 5.8 months, p=0.22) and shorter OS (11.3 months versus 12.6 months, p=0.15) than patients with non-amplified tumors. A Receiver Operating Characteristic (ROC) analysis was also performed in order to verify whether a better MYC GCN cut-off could discriminate between anti-EGFR sensitive and resistant cases. In this analysis, patients with mean MYC GCN ≥2.53 (N=199, 66.8%) had a significantly higher RR (32.2% versus 19.1%, p=0.02), a longer PFS (5.8 months versus 4.5 months, p=0.06) and a longer OS (12.3 months versus 11.4 months, p=0.59) than patients with mean GCN <2.53 (N=99, 33.2%). In order to assess the potential confounding effect of KRAS and BRAF status, we further analyzed the outcome of the 81 KRAS/BRAF wild-type patients according to MYC GCN. In this subset, a trend for improved RR (42% versus 20%, p=0.05), PFS (8.6 months versus 4.2 months, p=0.16) and OS (13.5 months versus 9.7 months, p=0.51) favored MYC FISH GCN ≥2.73 patients. Conclusions: MYC amplification is a rare event in mCRC, not significantly reducing sensitivity to anti-EGFR agents. A trend for better outcome was observed in presence of increased MYC GCN.

Correlation of cytidine deaminase polymorphisms and activity with clinical outcome in gemcitabine-/platinum-treated advanced non-small-cell lung cancer patients

BACKGROUND

The aim of this study was to evaluate whether cytidine deaminase (CDA) polymorphisms 79A>C and 435C>T and/or CDA enzymatic activity influenced clinical outcome in 126 advanced non-small-cell lung cancer patients treated with gemcitabine-platinum-regimens.

PATIENTS AND METHODS

CDA polymorphisms and activity were analysed by PCR and high-performance liquid chromatography, respectively. Univariate and multivariate analyses compared biological/clinical parameters with response, clinical benefit, time to progression (TtP) and overall survival (OS) using Pearson's χ(2) test, log-rank test and Cox proportional hazards model.

RESULTS

Patients with CDA A79A/A79C genotypes had significantly longer TtP (6.0 versus 3.0 months; P = 0.001) and OS (11.0 versus 5.0 months; P = 0.001) than patients with C79C genotype. Patients harbouring CDA C435C/C435T genotypes also had a longer OS (P = 0.025), but no correlations were observed with TtP. Conversely, patients with low-CDA activity had a significantly higher response rate (37.7% versus 13.8%; P = 0.006), clinical benefit (91.8% versus 51.7%; P < 0.001), as well as longer TtP (8.0 versus 3.0 months; P < 0.001) and OS (19.0 versus 6.0 months; P < 0.001). Furthermore, enzymatic activity emerged as an independent predictor for death/progression risk at multivariate analysis.

CONCLUSIONS

CDA enzymatic activity appears to be the strongest candidate biomarker of activity and efficacy of platinum-gemcitabine-based chemotherapy and should be validated in a prospective study.

Gefitinib for non-small-cell lung cancer treatment

INTRODUCTION

Gefitinib is an EGFR tyrosine kinase inhibitor (EGFR-TKI) that demonstrated efficacy in patients with advanced non-small cell lung cancer (NSCLC) across therapy lines. In the first-line setting, recent randomized Phase III trials comparing EGFR-TKIs versus platinum-based doublets demonstrated that in patients harboring an activating EGFR mutation, gefitinib is superior to chemotherapy in terms of response rate, progression-free survival, toxicity profile and quality of life, with a marginal positive effect on survival. In order to choose the best treatment, a molecular characterization is now mandatory, as part of baseline diagnostic procedures.

AREAS COVERED

All published data on gefitinib in lung cancer were analyzed using PubMed. The aim of this review is to summarize activity and safety data from major clinical trials of gefitinib in patients with advanced NSCLC.

EXPERT OPINION

EGFR-TKIs including gefitinib are the best option we can offer today in patients with EGFR mutation, regardless of treatment line. Administration of gefitinib to patients with advanced NSCLC is usually well-tolerated and it also appears to be feasible in special populations characterized by a significantly poorer risk:benefit ratio with standard chemotherapy, like elderly patients and patients with poor performance status.

Impact of ABCG2 polymorphisms on the clinical outcome and toxicity of gefitinib in non-small-cell lung cancer patients

AIMS

The current study investigates whether or not functional polymorphisms in the ATP-binding cassette transporter gene ABCG2 might affect gefitinib activity and/or toxicity in non-small-cell lung cancer (NSCLC) patients.

MATERIALS & METHODS

Towards this end, ABCG2 polymorphisms and expression were assessed in DNA and tumors from 94 NSCLC patients treated with gefitinib, whereas their associations with toxicity/response and time-to-progression/overall survival were evaluated using Pearson-χ(2) and log-rank-test, respectively.

RESULTS

Patients carrying an ABCG2 -15622T/T genotype or harboring at least one TT copy in the ABCG2 (1143C/T, -15622C/T) haplotype developed significantly more grade 2/3 diarrhea (p < 0.01). No associations were found between polymorphisms and outcome. Consistently, ABCG2 protein levels in tumors were not significantly different between patients harboring different ABCG2 variants.

CONCLUSION

The ABCG2 -15622C/T polymorphism and ABCG2 (1143C/T, -15622C/T) haplotype resulted in a gefitinib-dependent, moderate-to-severe diarrhea suggesting that these pharmacogenetic markers should be considered to optimize NSCLC treatment.

Abstract 1662: Association of EGFR and ABCG2 polymorphisms with gefitinib toxicity in non-small cell lung cancer patients

The use of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs), such as gefitinib and erlotinib, in non-small-cell lung cancer (NSCLC) patients is commonly associated with gastrointestinal (diarrhea) and skin (rash) toxicity. These adverse effects have a high interindividual variability, which might be partially explained by pharmacogenetic determinants. In particular, polymorphisms in EGFR and in ABCG2, an efflux transporter higly expressed in the gastrointestinal tract and able to transport gefitinib and other EGFR TKIs, might have an impact on gefitinib-associated toxicity. Therefore, the aim of our study was to evaluate associations between EGFR and ABCG2 polymorphisms with diarrhea and skin rash in gefitinib-treated NSCLC patients.

Four polymorphisms in EGFR (CA repeat length in the intron-1 (CA)n, EGFR −191C/A, EGFR −216G/T and EGFR R497K) and one in ABCG2 (ABCG2 421C/A) were assessed in DNA isolated from blood samples and/or paraffin-embedded tumor tissue from 96 NSCLC patients treated with gefitinib. Significant associations between EGFR and ABCG2 variants and toxicity were evaluated using the Fisher's exact test. In total, 87 and 85 patients had available data on polymorphisms and skin and gastrointestinal toxicity, respectively.

Diarrhea occurred in 33 (38.8%) of the 85 patients, with 6 of them experiencing high toxicity (grade=2-3 diarrhea). Skin rash was reported for 46 (52.9%) of the 87 patients, with 22 patients having grade&gt;1. The EGFR −191C/A polymorphism was strongly associated with grade&gt;1 diarrhea (P&lt;0.01). Five (33.3%) of the 15 patients carrying the CA or AA genotype developed severe diarrhea compared with only 1 (1.4%) of the 70 CC patients. The EGFR −216G/T polymorphism was also associated with high grade (&gt;1) diarrhea as all the patients who experienced grade 2 or 3 diarrhea carried the GG variant, while only 30.4% (24 out of 79) of the patients with low toxicity carried this variant (P&lt;0.01). Similar findings were found for the EGFR R497K polymorphism, with severe diarrhea being observed in 3 (30%) of the 10 patients with the AA genotype and in 3 (4.1%) of the 74 patients carrying the GG or GA variants (P=0.02). In contrast, none of these EGFR polymorphisms had a significant association with skin toxicity. Additionally, we found no association between EGFR (CA)n and the ABCG2 421C/A polymorphism with either gastrointestinal or skin toxicity.

In conclusion, our results demonstrate a clear association between the EGFR −191C/A, −216G/T and R497K with diarrhea in gefitinib-treated NSCLC patients, suggesting that these polymorphisms might be useful as pharmacogenetic markers for the selection of patients for treatment.

Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1662.

Association of polymorphisms in AKT1 and EGFR with clinical outcome and toxicity in non-small cell lung cancer patients treated with gefitinib

EGFR mutations are strongly predictive of epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor activity in non-small cell lung cancer (NSCLC), but resistance mechanisms are not completely understood. The interindividual variability in toxicity also points out to the need of novel pharmacogenetic markers to select patients before therapy. Therefore, we evaluated the associations between EGFR and AKT1 polymorphisms and outcome/toxicity in gefitinib-treated NSCLC patients. Polymorphic loci in EGFR, and AKT1, and EGFR and K-Ras mutations were assessed in DNA isolated from blood samples and/or paraffin-embedded tumor from 96 gefitinib-treated NSCLC patients. Univariate and multivariate analyses compared genetic variants with clinical efficacy and toxicity using Fisher's, log-rank test, and Cox's proportional hazards model. AKT1-SNP4 association with survival was also evaluated in 127 chemotherapy-treated/gefitinib-naive patients, whereas its relationship with AKT1 expression and gefitinib cytotoxicity was studied in 15 NSCLC cell lines. AKT1-SNP4 A/A genotype was associated with shorter time-to-progression (P = 0.04) and overall survival (P = 0.007). Multivariate analyses and comparison with the gefitinib-nontreated population underlined its predictive significance, whereas the in vitro studies showed the association of lower AKT1 mRNA levels with gefitinib resistance. In contrast, EGFR-activating mutations were significantly correlated with response, longer time-to-progression, and overall survival, whereas EGFR -191C/A (P < 0.001), -216 G/T (P < 0.01), and R497K (P = 0.02) polymorphisms were strongly associated with grade >1 diarrhea. AKT1-SNP4 A/A genotype seems to be a candidate biomarker of primary resistance, whereas EGFR -191C/A, -216G/T, and R497K polymorphisms are associated with diarrhea when using gefitinib in NSCLC patients, thus offering potential new tools for treatment optimization.

53BP1 represses mitotic catastrophe in syncytia elicited by the HIV-1 envelope

p53 binding protein-1 (53BP1) participates in checkpoint signaling during the DNA damage response (DDR) and during mitosis. In this study we report that 53BP1 aggregates in nuclear foci within syncytia elicited by the human immunodeficiency virus (HIV)-1 envelope. 53BP1 aggregation occurs as a consequence of nuclear fusion (karyogamy (KG)). It colocalizes partially with the promyelomonocytic leukemia protein (PML), and the ataxia telangiectasia mutated kinase (ATM), the two components of the DDR that mediate apoptosis induced by the HIV-1 envelope. ATM-dependent phosphorylation of 53BP1 on serines 25 and 1778 (53BP1S25P and 53BP1S1778P) occurs at these DNA damage foci. 53BP1S25P was also detected in syncytia present in the lymph nodes or frontal brain sections from HIV-1-infected carriers, as well as in peripheral blood mononucleated cells from HIV-1-infected individuals, correlating with viral load. Knockdown of 53BP1 caused HIV-1 envelope-induced syncytia to enter abnormal mitoses, leading to their selective destruction through mitochondrion-dependent and caspase-dependent pathways. In conclusion, depletion of 53BP1 triggers the demise of HIV-1-elicited syncytia through mitotic catastrophe.

A comparative study of the anti-inflammatory, anticoagulant, antiangiogenic, and antiadhesive activities of nine different fucoidans from brown seaweeds

The anti-inflammatory, antiangiogenic, anticoagulant, and antiadhesive properties of fucoidans obtained from nine species of brown algae were studied in order to examine the influence of fucoidan origin and composition on their biological activities. All fucoidans inhibited leucocyte recruitment in an inflammation model in rats, and neither the content of fucose and sulfate nor other structural features of their polysaccharide backbones significantly affected the efficacy of fucoidans in this model. In vitro evaluation of P-selectin-mediated neutrophil adhesion to platelets under flow conditions revealed that only polysaccharides from Laminaria saccharina, L. digitata, Fucus evanescens, F. serratus, F. distichus, F. spiralis, and Ascophyllum nodosum could serve as P-selectin inhibitors. All fucoidans, except that from Cladosiphon okamuranus carrying substantial levels of 2-O-alpha-D-glucuronopyranosyl branches in the linear (1-->3)-linked poly-alpha-fucopyranoside chain, exhibited anticoagulant activity as measured by activated partial thromboplastin time whereas only fucoidans from L. saccharina, L. digitata, F. serratus, F. distichus, and F. evanescens displayed strong antithrombin activity in a platelet aggregation test. The last fucoidans potently inhibited human umbilical vein endothelial cell (HUVEC) tubulogenesis in vitro and this property correlated with decreased levels of plasminogen-activator inhibitor-1 in HUVEC supernatants, suggesting a possible mechanism of fucoidan-induced inhibition of tubulogenesis. Finally, fucoidans from L. saccharina, L. digitata, F. serratus, F. distichus, and F. vesiculosus strongly blocked MDA-MB-231 breast carcinoma cell adhesion to platelets, an effect which might have critical implications in tumor metastasis. The data presented herein provide a new rationale for the development of potential drugs for thrombosis, inflammation, and tumor progression.