Long-term clinical benefit from salvage EGFR tyrosine kinase inhibitors in advanced non-small-cell lung cancer patients with EGFR wild-type tumors

Background. Erlotinib has been approved for the management of NSCLC patients after failure of the first or subsequent line of chemotherapy. Although the efficacy of erlotinib is clearly associated with the presence of EGFR mutations, there is a subset of patients with EGFR wild-type (EGFRwt) tumors who impressively respond. Patients and methods. Patients with EGFRwt NSCLC who received salvage (≥2nd line) treatment with erlotinib for a prolonged period (>6 months), were sought from the database of the Hellenic Oncology Research Group. We retrospectively analyzed the clinical, pathological and molecular characteristics of the patients with available tumor material. Results. Forty-four patients that received erlotinib for >6 months (median 10.1 months) were enrolled in the study. The majority of them were male, never-smokers with adenocarcinoma histology and a good performance status. KRAS and PIK3CA mutations were detected in 21% (9/42 tested) and 13% (4/30 tested) of the patients, respectively. The ALK-EML4 translocation was found in 10% (2/20 tested); there was no patient with HER2 or BRAF mutated tumor. Twelve (54.5%) tumor specimens were considered positive for EGFR-overexpression. Eleven patients experienced a partial response (objective response rate 25%; 95% CI 12-38%) and the remaining 33 had stable disease. The median progression-free survival and overall survival were 10.1 (95% CI 8.6-11.6 months) and 24.1 (95% CI 11.2-37 months), respectively. Conclusions. Treatment with erlotinib significantly improves the clinical outcome in a subset of NSCLC patients with EGFRwt tumors. Further molecular analysis of such tumor specimens could provide a more comprehensive characterization of this particular group of patients. Nevertheless, the presence of other mutations should not prevent the treating physician from using erlotinib at later lines of salvage therapy for NSCLC patients (AU)

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Long-term clinical benefit from salvage EGFR tyrosine kinase inhibitors in advanced non-small-cell lung cancer patients with EGFR wild-type tumors.

BACKGROUND: Erlotinib has been approved for the management of NSCLC patients after failure of the first or subsequent line of chemotherapy. Although the efficacy of erlotinib is clearly associated with the presence of EGFR mutations, there is a subset of patients with EGFR wild-type (EGFRwt) tumors who impressively respond. PATIENTS AND METHODS: Patients with EGFRwt NSCLC who received salvage (≥2nd line) treatment with erlotinib for a prolonged period (>6 months), were sought from the database of the Hellenic Oncology Research Group. We retrospectively analyzed the clinical, pathological and molecular characteristics of the patients with available tumor material. RESULTS: Forty-four patients that received erlotinib for >6 months (median 10.1 months) were enrolled in the study. The majority of them were male, never-smokers with adenocarcinoma histology and a good performance status. KRAS and PIK3CA mutations were detected in 21% (9/42 tested) and 13% (4/30 tested) of the patients, respectively. The ALK-EML4 translocation was found in 10% (2/20 tested); there was no patient with HER2 or BRAF mutated tumor. Twelve (54.5%) tumor specimens were considered positive for EGFR-overexpression. Eleven patients experienced a partial response (objective response rate 25%; 95% CI 12-38%) and the remaining 33 had stable disease. The median progression-free survival and overall survival were 10.1 (95% CI 8.6-11.6 months) and 24.1 (95% CI 11.2-37 months), respectively. CONCLUSIONS: Treatment with erlotinib significantly improves the clinical outcome in a subset of NSCLC patients with EGFRwt tumors. Further molecular analysis of such tumor specimens could provide a more comprehensive characterization of this particular group of patients. Nevertheless, the presence of other mutations should not prevent the treating physician from using erlotinib at later lines of salvage therapy for NSCLC patients.

PKM2 as a biomarker for chemosensitivity to front-line platinum-based chemotherapy in patients with metastatic non-small-cell lung cancer.

BACKGROUND: Tumour cells exclusively express the embryonic M2 isoform of pyruvate kinase (PKM2). PKM2 expression levels have been correlated with the effect of platinum compounds in cancer cell lines and xenograft models. The potential predictive role of PKM2 in patients with metastatic/advanced non-small-cell lung cancer (NSCLC) receiving platinum-based chemotherapy as first-line was investigated. METHODS: Quantitative real-time PCR was used to assess the expression of PKM2 in tumour samples from 148 and 157 NSCLC patients in the training and the validation set, respectively. All patients received front-line platinum-based chemotherapy. PKM2 mRNA expression was also analysed in a control group of 85 NSCLC patients treated with non-platinum containing regimens. RESULTS: In the training set, high PKM2 mRNA levels were associated with decreased progression-free survival (PFS; 4.9 months vs 6.4, P=0.006), overall survival (OS; 10.1 vs 17.0 months, P=0.01) and disease control rate (DCR; 57.7% vs 74.3%; P=0.021) compared to patients with low PKM2 levels. In the validation set, high PKM2 mRNA levels were also associated with deceased PFS (3.7 vs 5.9 months, P=0.006), OS (8.3 vs 16.8 months, P=0.003) and DCR (57.7% vs 70.9%; P=0.049) compared to those with low PKM2 mRNA levels. There was no correlation between the PKM2 mRNA levels and the PFS (5.6 vs 5.9, P=0.43) or the OS (9.8 vs 10.1, P=0.51) in the control group. Multivariate analysis revealed high PKM2 mRNA expression as an independent predictive factor for the poor patients' outcome. CONCLUSIONS: PKM2 expression may be a predictive biomarker of platinum sensitivity in advanced NSCLC patients treated with platinum-based chemotherapy.

A triplet combination with irinotecan (CPT-11), oxaliplatin (LOHP), continuous infusion 5-fluorouracil and leucovorin (FOLFOXIRI) plus cetuximab as first-line treatment in KRAS wt, metastatic colorectal cancer: a pilot phase II trial.

BACKGROUND: We conducted an open-label, pilot phase II trial to evaluate the efficacy and safety of FOLFOXIRI plus cetuximab as first-line treatment of patients with metastatic colorectal cancer (mCRC). METHODS: Thirty patients with KRAS wild-type mCRC, <70 years and with performance status 0-1 were included in the trial. RESULTS: Complete and partial responses were observed in 4 (13.3%) and 17 (56.7%) patients, respectively (overall response rate (ORR)=70%; 95% confidence interval (CI): 53.6%-86.4%); 8 patients (26.7%) had stable disease and 1 had progressive disease. The median time to tumour progression was 10.2 months (95% CI: 7.1-13.4) and the overall median survival time was 30.3 months (95% CI: 18.8-41.9). Secondary R0 resection was performed in 11 (37%) patients. Grade 3 or 4 diarrhoea and neutropenia were observed in 16 (53%) and 7 (23.3%) patients, respectively, and febrile neutropenia observed in 2 (6.6%) patients. Neurotoxicity grade 2 or 3 was reported in 7 (23.3%) and in 2 (6.7%) patients, respectively, and grade 3 rush was reported in 1 patient. CONCLUSION: The FOLFOXIRI/cetuximab combination presented increased activity in terms of response rate and R0 secondary liver metastases resection, and merits further investigation, especially in patients with initially unresectable disease confined to the liver.

Comparison of EGFR and K-RAS gene status between primary tumours and corresponding metastases in NSCLC.

In non-small-cell lung cancer (NSCLC), epidermal growth factor receptor (EGFR) and K-RAS mutations of the primary tumour are associated with responsiveness and resistance to tyrosine kinase inhibitors (TKIs), respectively. However, the EGFR and K-RAS mutation status in metastases is not well studied. We compared the mutation status of these genes between the primary tumours and the corresponding metastases of 25 patients. Epidermal growth factor receptor and K-RAS mutation status was different between primary tumours and corresponding metastases in 7 (28%) and 6 (24%) of the 25 patients, respectively. Among the 25 primary tumours, three 'hotspot' and two non-classical EGFR mutations were found; none of the corresponding metastases had the same mutation pattern. Among the five (20%) K-RAS mutations detected in the primary tumours, two were maintained in the corresponding metastasis. Epidermal growth factor receptor and K-RAS mutations were detected in the metastatic tumours of three (12%) and five (20%) patients, respectively. The expressions of EGFR and phosphorylated EGFR showed I 0 and 50% discordance, in that order. We conclude that there is substantial discordance in EGFR and K-RAS mutational status between the primary tumours and corresponding metastases in patients with NSCLC and this might have therapeutic implications when treatment with TKIs is considered.

'Classical' but not 'other' mutations of EGFR kinase domain are associated with clinical outcome in gefitinib-treated patients with non-small cell lung cancer.

'Classical' mutations in the EGFR tyrosine kinase domain (exons 18, 19 and 21) have been associated with sensitivity to tyrosine kinase inhibitors (TKIs) in patients with NSCLC. The aim of the current study was to evaluate whether other than the classical G719X, DEL19 and L858R mutations of EGFR confer sensitivity to TKIs. Genomic DNA was extracted from microdissected formalin-fixed paraffin-embedded tumour tissue from 86 patients treated with gefitinib. Exons 18, 19 and 21 were amplified and subjected to direct sequencing. Eleven (13%) patients harboured the classical exon's 18, 19 and 21 mutations, while 14 (16%) had 'other' variants. There was a significantly higher percentage of 'never-smoker' patients with 'classical' EGFR mutations (P=0.002). Among patients with 'classical' mutations 3 patients achieved PR and 7 SD, while in the 'other' mutations group 10 patients had SD as best response. In the wild-type group, there were 3 patients with PR and 25 with SD. Median TTP was 16, 64 (P=0.002) and 21 weeks and median survival was 36, 78 and 67 weeks for patients with wild-type, 'classical' and 'other' EGFR mutations, respectively. The clinical relevance of 'other' EGFR mutation variants remains uncertain and requires further assessment in a prospective study.

Functional analysis of the Saccharomyces cerevisiae YFR021w/YGR223c/YPL100w ORF family suggests relations to mitochondrial/peroxisomal functions and amino acid signalling pathways.

Saccharomyces cerevisiae YFR021w, YGR223c and YPL100w are paralogous ORFs of unknown function. Phenotypic analysis of overexpression, single-, double- and triple-ORF deletion strains under various growth conditions indicated mitochondria-related functions for all three ORFs. Two-hybrid screens of a yeast genomic library identified potentially interacting proteins for the three ORFs. Among these, the transcriptional activator Rtg3p interacted with both Yfr021wp and Ypl100wp and both ORF single deletions reduced the constitutive expression of the RTG-regulated CIT2 and DLD3 genes and caused typical retrograde response of CIT2 and DLD3 under growth conditions requiring functional mitochondria, indicating that YFR021w and YPL100w are also involved in unidentified mitochondrial functions. Ptr3p, a component of the amino acid sensor Ssy1p/Ptr3p, was also found as a two-hybrid interactant of Yfr021wp. Of the three single-ORF deletions, ypl100w Delta exhibited ptr3 Delta-similar phenotypes. These findings, combined with the fact that RTG-dependent expression is modulated by specific amino acids, suggested possible relations of Yfr021wp and Ypl100wp to amino acid signalling pathways. Under most conditions examined, the effects of the single- and double-ORF deletions indicated that YFR021w, YPL100w and YGR223c are not parts of the same pathway. We found no unique phenotype attributed to the deletion of YGR223c. However, its function interferes with the function of the other two ORFs, as revealed by the effects of double- and triple-ORF deletions.

The second cysteine-rich domain of Mac1p is a potent transactivator that modulates DNA binding efficiency and functionality of the protein.

Mac1p is a Saccharomyces cerevisiae DNA binding transcription factor that activates genes involved in copper uptake. A copper-induced N-C-terminal intramolecular interaction and copper-independent homodimerization affect its function. Here, we present a functional analysis of Mac1p deletion derivatives that attributes new roles to the second cysteine-rich (REPII) domain of the protein. This domain exhibits the copper-responsive potent transactivation function when assayed independently and, in the context of the entire protein, modulates the efficiency of Mac1p binding to DNA. The efficiency of binding to both copper-response promoter elements can determine the in vivo functionality of Mac1p independent of homodimerization.

Sequence divergence of the RNA polymerase shared subunit ABC14.5 (Rpb8) selectively affects RNA polymerase III assembly in Saccharomyces cerevisiae.

ABC14.5 (Rpb8) is a eukaryotic subunit common to all three nuclear RNA polymerases. In Saccharomyces cerevisiae, ABC14.5 (Rpb8) is essential for cell viability, however its function remains unknown. We have cloned and characterised the Schizosaccharomyces pombe rpb8(+) cDNA. We found that S.pombe rpb8, unlike the similarly diverged human orthologue, cannot substitute for S.cerevisiae ABC14. 5 in vivo. To obtain information on the function of this RNA polymerase shared subunit we have used S.pombe rpb8 as a naturally altered molecule in heterologous expression assays in S.cerevisiae. Amino acid residue differences within the 67 N-terminal residues contribute to the functional distinction of the two yeast orthologues in S.cerevisiae. Overexpression of the S.cerevisiae largest subunit of RNA polymerase III C160 (Rpc1) allows S.pombe rpb8 to functionally replace ABC14.5 in S.cerevisiae, suggesting a specific genetic interaction between the S.cerevisiae ABC14.5 (Rpb8) and C160 subunits. We provide further molecular and biochemical evidence showing that the heterologously expressed S.pombe rpb8 molecule selectively affects RNApolymerase III but not RNA polymerase I complex assembly. We also report the identification of a S.cerevisiae ABC14.5-G120D mutant which affects RNA polymerase III.

[Early orthodontic treatment]. / Proise orthodontike therapeia.

Early orthodontic treatment has recently become a subject of great interest among orthodontists since it is the result of the closest approach between the American and the European orthodontic trends. The early orthodontic treatment emerged from the better knowledge and deeper study of the philosophy of the functional, orthopedic and removable appliances as well as from the verification of their effectiveness, especially during childhood. An analysis of the term "Early orthodontic treatment" is being done in this study in contrast to the term "Early orthodontic management". Timing of orthodontic management of dentofacial deformities is quoted. The main points of a successful early orthodontic treatment as well as advantages and disadvantages, positive and negative criteria of it are mentioned.