Should epidermal growth factor receptor tyrosine kinase inhibitors be considered ideal drugs for the treatment of selected advanced non-small cell lung cancer patients?

TP53 mutations in circulating tumor DNA in advanced epidermal growth factor receptor-mutant lung adenocarcinoma patients treated with gefitinib

•

We evaluated 180 patients' EGFR and TP53 co-mutation types, who received gefitinib targeted therapy, through sequencing their ctDNA in plasma.

•

Patients with TP53 mutation is predictive of poor survival.

•

Patients with EGFR exon 19 and TP53 co-mutations had better prognosis value than those with EGFR L585R and TP53 co-mutations.

•

4.Patients with TP53 mutations, especially in exons 6 and 7, had a lower response rate and shorter PFS and OS when treated with gefitinib.

•

TP53 exon 5 mutation divided TP53 mutations in disruptive and non-disruptive types.

Tumor protein p53 (TP53) is a tumor suppressor gene and TP53 mutations are associated with poor prognosis in non-small cell lung cancer. However, the in-depth classification of TP53 and its relationship with treatment response and prognosis in epidermal growth factor receptor (EGFR)-mutant tumors treated with EGFR tyrosine kinase inhibitors are unclear. Circulating tumor DNA was prospectively collected at baseline in advanced treatment-naïve EGFR-mutant lung adenocarcinoma patients treated with gefitinib in an open-label, single-arm, prospective, multicenter, phase 2 clinical trial (BENEFIT trial) and analyzed using next-generation sequencing. Survival was estimated using the Kaplan–Meier method. Of the 180 enrolled patients, 115 (63.9%) harbored TP53 mutations. The median progression-free survival (PFS) and overall survival (OS) of patients with TP53-wild type tumors were significantly longer than those of patients with TP53-mutant tumors. Mutations in exons 5–8 accounted for 80.9% of TP53 mutations. Mutations in TP53 exons 6 and 7 were significantly associated with inferior PFS and OS compared to wild-type TP53. TP53 mutation also influenced the prognosis of patients with different EGFR mutations. Patients with TP53 and EGFR exon 19 mutations had significantly longer PFS and OS than patients with TP53 and EGFR L858R mutations, and both groups had worse survival than patients with only EGFR mutations. Patients with TP53 mutations, especially in exons 6 and 7, had a lower response rate and shorter PFS and OS when treated with gefitinib. Moreover, TP53 exon 5 mutation divided TP53 mutations in disruptive and non-disruptive types.

PTEN Loss as a Predictor of Tumor Heterogeneity and Poor Prognosis in Patients With EGFR-mutant Advanced Non-small-cell Lung Cancer Receiving Tyrosine Kinase Inhibitors

BACKGROUND

Rapid disease progression of patients with advanced epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer (NSCLC) has been recently associated with tumor heterogeneity, which may be mirrored by coexisting concomitant alterations. The aim of this analysis was to investigate the correlation between loss of function of PTEN and the efficacy of tyrosine kinase inhibitors in this population.

MATERIALS AND METHODS

Archival tumor blocks from patients with EGFR-mutant NSCLC who were administered upfront tyrosine kinase inhibitors were retrospectively collected. The status of 4 genes (PTEN, TP53, c-MET, IGFR) was evaluated by immunohistochemistry, and it was correlated with overall response rate, overall survival (OS), and progression-free survival (PFS).

RESULTS

Fifty-one patients were included. In multivariate analysis, PTEN loss (hazard ratio [HR], 3.46; 95% confidence interval [CI], 1.56-7.66; P = .002), IGFR overexpression (HR, 2.22; 95% CI, 1.03-4.77; P = .04), liver metastases (HR, 3.55; 95% CI, 1.46-8.65; P = .005), and Eastern Cooperative Oncology Group performance status (ECOG PS) ≥ 1 (HR, 2.57; 95% CI, 1.04-6.34; P = .04) were significantly associated with shorter PFS. Patients with PTEN loss had a median PFS of 6 months (2-year PFS, 11.6%), whereas patients without PTEN loss had a median PFS of 18 months (2-year PFS, 43.6%) (log-rank P < .005). In the multivariate analysis, PTEN loss (HR, 5.92; 95% CI, 2.37-14.81; P < .005), liver metastases (HR, 2.63; 95% CI, 1.06-6.51; P = .037), and ECOG PS ≥ 1 (HR, 2.80; 95% CI, 1.15-6.81; P = .024) were significantly associated with shorter OS. Patients with PTEN loss had a median OS of 6 months (2-year OS, 12.2%), whereas in patients without PTEN loss, OS was not reached (2-year OS, 63.9%) (log-rank P < .0005).

CONCLUSIONS

A low-cost and reproducible immunohistochemistry assay for PTEN loss analysis represents a potential tool for identifying tumor heterogeneity in patients with advanced EGFR-mutant NSCLC.

Next Generation Sequencing-Based Profiling of Cell Free DNA in Patients with Advanced Non-Small Cell Lung Cancer: Advantages and Pitfalls

Lung cancer (LC) is the main cause of death for cancer worldwide and non-small cell lung cancer (NSCLC) represents the most common histology. The discovery of genomic alterations in driver genes that offer the possibility of therapeutic intervention has completely changed the approach to the diagnosis and therapy of advanced NSCLC patients, and tumor molecular profiling has become mandatory for the choice of the most appropriate therapeutic strategy. However, in approximately 30% of NSCLC patients tumor tissue is inadequate for biomarker analysis. The development of highly sensitive next generation sequencing (NGS) technologies for the analysis of circulating cell-free DNA (cfDNA) is emerging as a valuable alternative to assess tumor molecular landscape in case of tissue unavailability. Additionally, cfDNA NGS testing can better recapitulate NSCLC heterogeneity as compared with tissue testing. In this review we describe the main advantages and limits of using NGS-based cfDNA analysis to guide the therapeutic decision-making process in advanced NSCLC patients, to monitor the response to therapy and to identify mechanisms of resistance early. Therefore, we provide evidence that the implementation of cfDNA NGS testing in clinical research and in the clinical practice can significantly improve precision medicine approaches in patients with advanced NSCLC.

The Presence of Concomitant Mutations Affects the Activity of EGFR Tyrosine Kinase Inhibitors in EGFR-Mutant Non-Small Cell Lung Cancer (NSCLC) Patients

Recent findings suggest that a fraction of EGFR-mutant non-small-cell lung cancers (NSCLC) carry additional driver mutations that could potentially affect the activity of EGFR tyrosine kinase inhibitors (TKIs). We investigated the role of concomitant KRAS, NRAS, BRAF, PIK3CA, MET and ERBB2 mutations (other mutations) on the outcome of 133 EGFR mutant patients, who received first-line therapy with EGFR TKIs between June 2008 and December 2014. Analysis of genomic DNA by Next Generation Sequencing (NGS) revealed the presence of hotspot mutations in genes other than the EGFR, including KRAS, NRAS, BRAF, ERBB2, PIK3CA, or MET, in 29/133 cases (21.8%). A p.T790M mutation was found in 9/133 tumour samples (6.8%). The progression free survival (PFS) of patients without other mutations was 11.3 months vs. 7 months in patients with other mutations (log-rank test univariate: p = 0.047). In a multivariate Cox regression model including the presence of other mutations, age, performance status, smoking status, and the presence of p.T790M mutations, the presence of other mutations was the only factor significantly associated with PFS (Hazard Ratio 1.63, 95% CI 1.04⁻2.58; p = 0.035). In contrast, no correlation was found between TP53 mutations and patients' outcome. These data suggest that a subgroup of EGFR mutant tumours have concomitant driver mutations that might affect the activity of first-line EGFR TKIs.

Addressing the elephant in the room, therapeutic resistance in non-small cell lung cancer, with epigenetic therapies

Like Chinese boxes nesting inside each other, the classification of non-small cell lung cancer (NSCLC) is subdivided into smaller and smaller subtypes on the basis of histological and molecular attributes. The latter characterizes NSCLC by its molecular alterations and the identification of inhibitors that target these cancer-specific "driver" mutations. Despite the initial promise of precision-guided therapies to inhibit a finer and finer array of molecular subcategories, despite even the curative potential of immunotherapeutic checkpoint blockade, in particular, casualties still abound and true clinical success stories are few and far between; the ever-present, if sometimes unmentioned, "elephant in the room", is the acquisition of resistance, which, sooner or later, rears its ugly head to undermine treatment success and shorten survival. Emerging data suggests that epigenetic therapies are able to reprogram the aberrant tumor-associated epigenome and 'tame the beast of resistance', thereby prolonging survival. This article reviews the role of epigenetic dysregulation in NSCLC, explores PFS2 as a possible surrogate endpoint, briefly mentions possible biomarkers and highlights combinatorial treatment epigenetic strategies to "prime" tumors and reverse resistance.

Imatinib-induced ophthalmological side-effects in GIST patients are associated with the variations of EGFR, SLC22A1, SLC22A5 and ABCB1

Imatinib-induced ophthalmological side-effects, including conjunctiva hemorrhage and periorbital oedema, although very common and still remain relatively little understood. The present study investigated the effects of genetic polymorphisms of drug targets and membrane transporters on these side effects. We found that the minor allele of EGFR rs10258429 and SLC22A1 rs683369 were significant risk determinants of conjunctival hemorrhage with OR of 7.061 (95%CI=1.791-27.837, P=0.005 for EGFR rs10258429 CT+TT vs CC), and 4.809 (95%CI=1.267-18.431, P=0.021 for SLC22A1 rs683369 GG+CG vs CC). The minor allele of SLC22A5 rs274558 and ABCB1 rs2235040 were protective factors to periorbital oedema with OR of 0.313 (95%CI=0.149-0.656, P=0.002 for SLC22A5 rs274558 AA+AG vs GG), and 0.253 (95%CI=0.079-0.805, P=0.020 for ABCB1 rs2235040 CT vs CC). These results indicated that variants in EGFR, SLC22A1, SLC22A5 and ABCB1 influenced the incidence of Imatinib-induced ophthalmological toxicities, and polymorphism analyses in associated genes might be beneficial to optimize Imatinib treatment.

Accuracy of next-generation sequencing for the identification of clinically relevant variants in cytology smears in lung adenocarcinoma

BACKGROUND

Minimally invasive diagnostic procedures such as needle-core biopsy and fine-needle aspiration provide adequate material for molecular analyses. Advances in precision oncology are trending toward the interrogation of limited amounts of genomic material to guide clinical and therapeutic decisions. The aim of this study was to investigate the minimum cellularity needed on cytologic smears for the identification of clinically relevant variants with next-generation sequencing (NGS).

METHODS

Thirty cases of cytologically diagnosed, resection-proven primary lung adenocarcinoma were identified. Nineteen of the 30 cases were known to harbor actionable variants. One Diff-Quik (DQ)-stained slide and 1 Papanicolaou (Pap)-stained slide were selected from each case. Cases were categorized as containing fewer than 100 tumor cells, 100 to 500 tumor cells, or more than 500 tumor cells. NGS was performed on the Ion Torrent platform.

RESULTS

NGS was successfully performed on all cell blocks and on 90% of the smears. Paired DQ and Pap smears showed similar cellularity, and cases that differed in cellularity were within 1 category of each other. The cases with more than 100 tumor cells had a 93% success rate; this was significantly different from the situation for cases with fewer than 100 tumor cells, which were successfully sequenced only 67% of the time. Overall, NGS was able to provide clinically relevant information for 83% of DQ smears and for 90% of Pap smears tested.

CONCLUSIONS

The data show a significantly higher likelihood of successful NGS with cytologic smears with more than 100 tumor cells. There was a trend for a higher NGS success rate with Pap smears versus DQ smears. Cancer Cytopathol 2017;125:398-406. © 2017 American Cancer Society.

The efficacy and safety of nivolumab in previously treated advanced non-small-cell lung cancer: a meta-analysis of prospective clinical trials

Background

Nivolumab (BMS-936558/ONO-4538) was the first monoclonal antibody targeting programmed death (PD)-1. So far, a number of clinical trials on nivolumab have showed satisfactory efficacy in treating non-small-cell lung cancer (NSCLC). Herein, we present a meta-analysis evaluating the efficacy and safety of nivolumab for previously treated advanced NSCLC patients.

Methods

Electronic databases were searched for eligible literature. Data of objective response rate (ORR), disease control rate, overall survival, progression-free survival, and adverse effects (AEs) were extracted and pooled. Outcomes analyzed and presented in this study were according to the original data from nivolumab 3 mg/kg.

Results

In general, nine trials with 817 patients were included in this meta-analysis. The pooled ORR, disease control rate, 1-year overall survival rate, and 1-year progression-free survival rate were 20% (95% confidence interval [CI]: 17%–23%), 36% (95% CI: 22%–51%), 47% (95% CI: 40%–53%), 21% (95% CI: 18%–24%), respectively. In addition, the rate of grade 3–4 AEs was only 8% (95% CI: 6%–12%). Subgroup analysis showed no significant difference in terms of ORR between squamous and non-squamous NSCLC (odds ratio 1.23, 95% CI: 0.63–2.39, P=0.51). However, significantly greater ORR was presented in programmed cell death ligand 1 (PD-L1) positive cohort (ORR 31%, 95% CI: 24%–38%), compared to PD-L1 negative cohort (ORR 12%, 95% CI: 9%–17%). The odds ratio for objective response to nivolumab in PD-L1 positive cases relative to negative cases was 3.08 (95% CI: 1.87–5.08, P<0.0001).

Conclusion

In conclusion, nivolumab is a promising second-line agent for previously treated advanced NSCLC with manageable AEs. Both squamous and non-squamous NSCLC patients showed similar efficacy. In addition, patients with positive PD-L1 expression had better response from nivolumab.

Microabstract

We present a meta-analysis evaluating the efficacy and safety of nivolumab for previously treated advanced NSCLC patients. In our study, nivolumab is a promising second-line agent for previously treated advanced NSCLC with manageable AEs. Both squamous and non-squamous NSCLC patients showed similar efficacy. In addition, patients with positive PD-L1 expression had better response from nivolumab.

EGFR mutations in lung cancer: from tissue testing to liquid biopsy

ABSTRACT  The presence of EGFR mutations predicts the sensitivity to EGF receptor (EGFR)-tyrosine kinase inhibitors in a molecularly defined subset of non-small-cell lung carcinoma (NSCLC) patients. For this reason, EGFR testing of NSCLC is required to provide personalized treatment options and better outcomes for NSCLC patients. As surgery specimens are not available in the majority of NSCLC, other currently available DNA sources are small biopsies and cytological samples, providing however limited and low-quality material. In order to address this issue, the use of surrogate sources of DNA, such as blood, serum and plasma samples, which often contains circulating free tumor DNA or circulating tumor cells, is emerging as a new strategy for tumor genotyping.

The Difference of Clinical Characteristics Between Patients With Exon 19 Deletion and Those With L858R Mutation in Nonsmall Cell Lung Cancer

Recent studies have demonstrated that exon 19 deletion (19 Del) and exon 21 L858R mutation (L858R) are 2 different types of sensitive epidermal growth factor receptor (EGFR) mutations in nonsmall cell lung cancer (NSCLC). However, whether there are some differences between those 2 groups in baseline clinical characteristics is still unclear.We enrolled consecutive 1271 NSCLC patients detected with either 19 Del or L858R and collected their baseline clinical characteristics including age, sex, comorbidity, smoking and drinking status, body mass index (BMI), TNM stage, histologic type, differentiation, tumor maximum diameter (TMD), and CEA level. χ test and multivariate logistic regression analysis were used to compare the difference.We found a higher percentage of 19 Del in younger patients group (< = 50 yr) than L858R (P < 0.001) through χ test. Besides, patients with 19 Del have higher risk of lymph node metastasis (P < 0.001). However, there were no significant differences in other items of clinical characteristics between 19 Del and L858R. Multivariate analysis showed similar significant results. Subgroup analysis in different age groups (10 yr as an interval) and N stages (stratified by N0, N1, N2, and N3) also indicated above-mentioned trends.NSCLC patients with 19 Del are more likely to be young and have lymphatic metastasis than those with L858R. Age and N stage might be considered in predicting EGFR mutation type in NSCLC.

Assessment of high-sensitive methods for the detection of EGFR mutations in circulating free tumor DNA from NSCLC patients

AIM

We assessed the ability of the Therascreen(®) kit (plasma-Therascreen) and of a peptide nucleic acids (PNA)-clamp approach to detect EGFR mutations in plasma-derived circulating-free tumor DNA (cftDNA) from non-small-cell lung cancer patients.

MATERIALS & METHODS

cftDNA from 96 patients was analyzed for exon 19 deletions and the p.L858R mutation, using both plasma-Therascreen and PNA-clamp-based assays.

RESULTS

None of the 70 EGFR wild-type patients showed EGFR mutations in cftDNA with both techniques (specificity: 100%). In 17/26 EGFR-mutant patients, plasma-Therascreen analysis confirmed the mutation identified in the primary tumor (analytical sensitivity: 65.4%). Similar results were obtained with the PNA-clamp method.

CONCLUSION

Both approaches were specific and sensitive for EGFR mutational analysis of cftDNA in non-small-cell lung cancer patients.

Evaluation of the efficacy and safety of anti-PD-1 and anti-PD-L1 antibody in the treatment of non-small cell lung cancer (NSCLC): a meta-analysis

BACKGROUND

Currently, blockade of the programmed cell death 1 (PD-1)/PD-1 ligand 1 (PD-L1) signaling pathway has been proved one of the most promising immunotherapeutic strategies against cancer. Several antibodies have been developed to either block the PD-1 or its ligand PD-L1 are under development. So far, a series of phase I trials on PD-1/PD-L1 antibodies for non-small cell lung cancer (NSCLC) have been completed, without reports of results from phase II studies. Thus, we sought to perform a meta-analysis incorporating all available evidences to evaluate the efficacy and safety of PD-1 or PD-L1 inhibition therapy.

METHODS

Electronic databases were searched for eligible literatures. Data of objective respond rate (ORR) and rate of adverse effects (AEs) with 95% confidence interval (CI) evaluated by immunohistochemistry (IHC) was extracted. The outcomes were synthesized based on random-effect model. Subgroup analyses were proposed.

RESULTS

In overall, ORR in the whole population with PD-1 blockage treatment is 22.5% (95% CI: 17.6% to 28.2%). Additionally, the rate of Grade 3-4 AEs is 16.7% (95% CI: 6.5% to 36.8%) and drug-related death rate is 2.5% (95% CI: 1.3% to 4.6%). As for patients with PD-L1 inhibition therapy, an overall ORR is 19.5% (95% CI: 13.2% to 27.7%). A higher rate of Grade 3-4 AEs (31.7%, 95% CI: 14.2% to 56.5%) is observed with a lower drug-related death rate (1.8%, 95% CI: 0.4% to 8.3%). In exploratory analyses of anti-PD-1 agents, we observed that greater ORR was presented in the median-dose cohort (3 mg/kg) than that of both low-dose (1 mg/kg) and high-dose (10 mg/kg) cohort (low-dose vs. median-dose: OR =0.12, P=0.0002; median-dose vs. high-dose: OR =1.47, P=0.18).

CONCLUSIONS

Anti-PD-1 and anti PD-L1 antibodies showed objective responses in approximately one fourth NSCLC patients with a tolerable adverse-effect profile. In addition, median-dose (3 mg/kg) might be a preferential dosage of anti-PD-1 agents.

Genomics driven-oncology: challenges and perspectives

Molecularly defined subgroups of tumors characterized by specific driver mutations have been identified in the majority of cancers. The availability of novel drugs capable of targeting signaling pathways activated by genetic derangements has led to hypothesize the possibility to treat patients based on their genomic profile. A clear example is represented by lung adenocarcinoma for which it has been possible to identify driver genetic alterations in approximately 75% of the cases. Among these, RET fusion transcripts are detectable in about 1–2% of lung adenocarcinomas and might represent targets for therapeutic intervention with RET kinase inhibitors. However, a number of issues need to be addressed to make genomics-driven oncology routinely accessible for cancer patients, including: 1) the availability of novel methods in molecular diagnostics that allow a comprehensive molecular characterization of lung tumors starting from a low input DNA/RNA; 2) identification of reliable and reproducible biomarkers of response/resistance to targeted agents; 3) the assessment of the role of tumor heterogeneity in the response to drugs targeting molecular pathways.

CUL4A overexpression enhances lung tumor growth and sensitizes lung cancer cells to erlotinib via transcriptional regulation of EGFR

Background

CUL4A has been proposed as oncogene in several types of human cancer, but its clinical significance and functional role in human non-small cell lung cancer (NSCLC) remain unclear.

Methods

Expression level of CUL4A was examined by RT-PCR and Western blot. Forced expression of CUL4A was mediated by retroviruses, and CUL4A silencing by shRNAs expressing lentiviruses. Growth capacity of lung cancer cells was measured by MTT in vitro and tumorigenesis in vivo, respectively.

Results

We found that CUL4A was highly expressed in human lung cancer tissues and lung cancer cell lines, and this elevated expression positively correlated with disease progression and prognosis. Overexpression of CUL4A in human lung cancer cell lines increased cell proliferation, inhibited apoptosis, and subsequently conferred resistance to chemotherapy. On other hand, silencing CUL4A expression in NSCLC cells reduced proliferation, promoted apoptosis and resulted in tumor growth inhibition in cancer xenograft model. Mechanistically, we revealed CUL4A regulated EGFR transcriptional expression and activation, and subsequently activated AKT. Targeted inhibition of EGFR activity blocked these CUL4A induced oncogenic activities.

Conclusions

Our results highlight the significance of CUL4A in NSCLC and suggest that CUL4A could be a promising therapy target and a potential biomarker for prognosis and EGFR target therapy in NSCLC patients.

Electronic supplementary material

The online version of this article (doi:10.1186/1476-4598-13-252) contains supplementary material, which is available to authorized users.

Detection of EGFR mutations by TaqMan mutation detection assays powered by competitive allele-specific TaqMan PCR technology

Epidermal growth factor receptor (EGFR) mutations in non-small-cell lung cancer (NSCLC) are predictive of response to treatment with tyrosine kinase inhibitors. Competitive Allele-Specific TaqMan PCR (castPCR) is a highly sensitive and specific technology. EGFR mutations were assessed by TaqMan Mutation Detection Assays (TMDA) based on castPCR technology in 64 tumor samples: a training set of 30 NSCLC and 6 colorectal carcinoma (CRC) samples and a validation set of 28 NSCLC cases. The sensitivity and specificity of this method were compared with routine diagnostic techniques including direct sequencing and the EGFR Therascreen RGQ kit. Analysis of the training set allowed the identification of the threshold value for data analysis (0.2); the maximum cycle threshold (Ct = 37); and the cut-off ΔCt value (7) for the EGFR TMDA. By using these parameters, castPCR technology identified both training and validation set EGFR mutations with similar frequency as compared with the Therascreen kit. Sequencing detected rare mutations that are not identified by either castPCR or Therascreen, but in samples with low tumor cell content it failed to detect common mutations that were revealed by real-time PCR based methods. In conclusion, our data suggest that castPCR is highly sensitive and specific to detect EGFR mutations in NSCLC clinical samples.

Molecular Targeted Drugs and Biomarkers in NSCLC, the Evolving Role of Individualized Therapy

Lung cancer first line treatment has been directed from the non-specific cytotoxic doublet chemotherapy to the molecular targeted. The major limitation of the targeted therapies still remains the small number of patients positive to gene mutations. Furthermore, the differentiation between second line and maintenance therapy has not been fully clarified and differs in the clinical practice between cancer centers. The authors present a segregation between maintenance treatment and second line and present a possible definition for the term “maintenance” treatment. In addition, cancer cell evolution induces mutations and therefore either targeted therapies or non-specific chemotherapy drugs in many patients become ineffective. In the present work pathways such as epidermal growth factor, anaplastic lymphoma kinase, met proto-oncogene and PI3K are extensively presented and correlated with current chemotherapy treatment. Future, perspectives for targeted treatment are presented based on the current publications and ongoing clinical trials.

Molecular typing of lung adenocarcinoma on cytological samples using a multigene next generation sequencing panel

Identification of driver mutations in lung adenocarcinoma has led to development of targeted agents that are already approved for clinical use or are in clinical trials. Therefore, the number of biomarkers that will be needed to assess is expected to rapidly increase. This calls for the implementation of methods probing the mutational status of multiple genes for inoperable cases, for which limited cytological or bioptic material is available. Cytology specimens from 38 lung adenocarcinomas were subjected to the simultaneous assessment of 504 mutational hotspots of 22 lung cancer-associated genes using 10 nanograms of DNA and Ion Torrent PGM next-generation sequencing. Thirty-six cases were successfully sequenced (95%). In 24/36 cases (67%) at least one mutated gene was observed, including EGFR, KRAS, PIK3CA, BRAF, TP53, PTEN, MET, SMAD4, FGFR3, STK11, MAP2K1. EGFR and KRAS mutations, respectively found in 6/36 (16%) and 10/36 (28%) cases, were mutually exclusive. Nine samples (25%) showed concurrent alterations in different genes. The next-generation sequencing test used is superior to current standard methodologies, as it interrogates multiple genes and requires limited amounts of DNA. Its applicability to routine cytology samples might allow a significant increase in the fraction of lung cancer patients eligible for personalized therapy.

The S492R EGFR ectodomain mutation is never detected in KRAS wild-type colorectal carcinoma before exposure to EGFR monoclonal antibodies

The activity of the epidermal growth factor receptor (EGFR) antibodies cetuximab and panitumumab in metastatic colorectal carcinoma (mCRC) is significantly limited by molecular mechanisms leading to intrinsic or acquired resistance. The S492R mutation of the EGFR, which is caused by either the 1476C>A or the 1474A>C substitution, interferes with binding to cetuximab but not to panitumumab, and has been detected in mCRC with acquired resistance to cetuximab. Since mechanisms of acquired and intrinsic resistance to EGFR monoclonal antibodies in CRC significantly overlap, we evaluated the frequency of the S492R mutation in a series of KRAS-exon 2 wild-type CRC patients. Genomic DNA was extracted from formalin fixed paraffin embedded (FFPE) tissues that were obtained from 505 systemic therapy-naïve CRC patients. A PCR/sequencing method for the detection of the S492R mutation was developed, by using as positive control a plasmid in which the 1474A>C mutation was generated by site directed mutagenesis. The lowest level of detection of this assay was approximately 10% mutant DNA in a background of wild-type DNA. PCR sequencing analysis revealed no S492R mutations in any of the analyzed 505 CRC specimens. Our findings suggest that the S492R mutation is not involved in primary resistance to cetuximab in CRC. Therefore, patients with mCRC should not be routinely screened for this mutation prior therapy with cetuximab.

A multicenter randomized phase IIb efficacy study of Vx-001, a peptide-based cancer vaccine as maintenance treatment in advanced non-small-cell lung cancer: treatment rationale and protocol dynamics

We present the treatment rationale and study design of a multicenter, open-label, randomized, 2-arm, phase IIb study. Patients with stage IV or recurrent stage I to III non-small-cell lung cancer (NSCLC) whose disease does not progress after 4 cycles of first-line platinum-based chemotherapy will be randomized in a 1:1 ratio to 1 of 2 study arms. Patients will receive the cancer vaccine Vx-001 + Montanide ISA51 VG (Seppic, Paris, France) adjuvant subcutaneously, at a dose of 2 mg, or placebo + Montanide ISA51 VG adjuvant subcutaneously. The vaccination protocol comprises 2 injections with the TYR-Vx001 or placebo (1 at day 0 and another at week 3) and 4 injections with the ARG-Vx001 or placebo, at weeks 6, 9, 12, and 15. After the treatment assessment at week 18, patients will receive the ARG-Vx001 or placebo every 12 weeks starting from week 27 until disease progression, unacceptable toxicity, withdrawal of informed consent, or death. The primary end point of this study is the survival rate at 12 months. Secondary end points include time-to-event comparison of overall survival and comparison of time to treatment failure. Exploratory objectives include comparison of disease control rate after the end of subsequent second-line treatments, comparisons of vaccine immune responses, comparison of survival rate at 12 months in patients with vaccine-induced immune response detected after the second and sixth injections, identification of biomarkers on lymphocytes and on tumors, and comparison of safety and tolerability.