EGFR amplification and lack of activating mutations in metaplastic breast carcinomas

Metaplastic breast carcinomas are reported to harbour epidermal growth factor receptor (EGFR) overexpression in up to 80% of the cases, but EGFR gene amplification is the underlying genetic mechanism in around one-third of these. In this study, EGFR gene amplification as defined by chromogenic in situ hybridization and protein overexpression was examined in a cohort of 47 metaplastic breast carcinomas. Furthermore, the presence of activating EGFR mutations in exons 18, 19, 20, and 21 was investigated. Thirty-two cases showed EGFR overexpression and of these, 11 (34%) harboured EGFR gene amplification. In addition, EGFR amplification showed a statistically significant association with EGFR overexpression (p < 0.0094) and was restricted to carcinomas with homologous metaplasia. Ten cases, five with and five without EGFR amplification, were subjected to microarray-based CGH, which demonstrated that EGFR copy number gain may occur by amplification of a discrete genomic region or by gains of the short arm of chromosome 7 with a breakpoint near the EGFR gene locus, the minimal region of amplification mapping to EGFR, LANCL2, and SEC61G. No activating EGFR mutations were identified, suggesting that this is unlikely to be a common alternative underlying genetic mechanism for EGFR expression in metaplastic breast carcinomas. Given that metaplastic breast carcinomas are resistant to conventional chemotherapy or hormone therapy regimens and that tumours with EGFR amplification are reported to be sensitive to EGFR tyrosine kinase inhibitors, these findings indicate that further studies are warranted to explore EGFR tyrosine kinase inhibitors as potential therapeutic agents for metaplastic breast carcinomas harbouring amplification of 7p11.2.     

Non-existence of caveolin-1 gene mutations in human breast cancer

Caveolin-1 is the principal constituent protein of caveolae, which are specialised plasma membrane invaginations with diverse biological roles. Caveolin-1 is suggested to have tumour suppressive functions and CAV1 gene mutations have been reported in 20% of breast cancers. The aim of the present study was to evaluate the frequency of CAV1 mutations in a large cohort of optimally accrued breast cancers. Two independent series of breast cancer samples were analysed: 82 fresh-frozen grade 3 and 158 formalin-fixed paraffin-embedded invasive ductal carcinomas of no special type were consecutively accrued and subjected to microdissection of neoplastic epithelial cells prior to DNA extraction. Thirty-nine human breast cancer cell lines were also included in this study. The trans-membrane region of CAV1 and adjacent sequences, where mutations are reported to cluster, were amplified by PCR, followed by direct sequencing and mutational analysis. None of the reported CAV1 gene mutations, including CAV1 ^P132L, were identified in either clinical samples (95% CI: 0–1.5%) or human breast cancer cell lines analysed. One novel non-synonymous germline polymorphism was detected within a reported region of high mutational frequency. This study does not corroborate the reported frequent occurrence of CAV1 gene mutations, including CAV1 ^P132L, in primary human breast carcinomas. Our findings demonstrate that if CAV1 mutations do exist, their overall mutational frequency is substantially lower than positive reports have suggested. Taken together with other studies, which have also failed to identify CAV1 mutations, our data call into question the existence and biological and clinical relevance of CAV1 gene mutations in human breast cancer.     

Functional characterization of the 19q12 amplicon in grade III breast cancers

Introduction

The 19q12 locus is amplified in a subgroup of oestrogen receptor (ER)-negative grade III breast cancers. This amplicon comprises nine genes, including cyclin E1 (CCNE1), which has been proposed as its 'driver'. The aim of this study was to identify the genes within the 19q12 amplicon whose expression is required for the survival of cancer cells harbouring their amplification.

Methods

We investigated the presence of 19q12 amplification in a series of 313 frozen primary breast cancers and 56 breast cancer cell lines using microarray comparative genomic hybridisation (aCGH). The nine genes mapping to the smallest region of amplification on 19q12 were silenced using RNA interference in phenotypically matched breast cancer cell lines with (MDA-MB-157 and HCC1569) and without (Hs578T, MCF7, MDA-MB-231, ZR75.1, JIMT1 and BT474) amplification of this locus. Genes whose silencing was selectively lethal in amplified cells were taken forward for further validation. The effects of cyclin-dependent kinase 2 (CDK2) silencing and chemical inhibition were tested in cancer cells with and without CCNE1 amplification.

Results

19q12 amplification was identified in 7.8% of ER-negative grade III breast cancer. Of the nine genes mapping to this amplicon, UQCRFS1, POP4, PLEKHF1, C19ORF12, CCNE1 and C19ORF2 were significantly over-expressed when amplified in primary breast cancers and/or breast cancer cell lines. Silencing of POP4, PLEKHF1, CCNE1 and TSZH3 selectively reduced cell viability in cancer cells harbouring their amplification. Cancer cells with CCNE1 amplification were shown to be dependent on CDK2 expression and kinase activity for their survival.

Conclusions

The 19q12 amplicon may harbour more than a single 'driver', given that expression of POP4, PLEKHF1, CCNE1 and TSZH3 is required for the survival of cancer cells displaying their amplification. The observation that cancer cells harbouring CCNE1 gene amplification are sensitive to CDK2 inhibitors provides a rationale for the testing of these chemical inhibitors in a subgroup of patients with ER-negative grade III breast cancers.     

A phase II trial of erlotinib as front-line treatment in clinically selected patients with non-small-cell lung cancer

BackgroundThe purpose of this study was to evaluate the efficacy of erlotinib as front-line treatment in clinically selected patients with non–small-cell lung cancer (NSCLC).Patients and MethodsForty-nine previously untreated white patients who had stage IIIB/IV pulmonary adenocarcinoma or bronchoalveolar carcinoma and who were nonsmokers or former light smokers were treated with erlotinib 150 mg daily, irrespective of the EGFR mutation status.ResultsIn an intention-to-treat analysis, the overall response rate (ORR) was 24.5%. The median progression-free survival (PFS) was 6.7 months, the median overall survival (OS) was 15.5 months, and the 1-year survival rate was 61.3%. Among the 36 patients for whom tumor material was available, 9 (25%) had activating EGFR mutations. The ORR was 66.7% in patients with activating EGFR mutations and 14.8% in patients with wild-type EGFR (2P = .006). In patients with activating EGFR mutations, the OS has not been reached, whereas it was 12.9 months in patients with EGFR wild type (2P = .045). Twenty-four patients had a PFS of > 6 months; 11 (45.8%) of them had EGFR wild type and 7 (29.1%) had EGFR mutation.ConclusionsThe selection of patients for treatment with EGFR-directed tyrosine kinase inhibitors (TKIs) should be based on mutation testing. However use of clinical (smoking status) and pathologic (adenocarcinoma) criteria may identify a subgroup of patients with advanced/metastatic NSCLC who can benefit from front-line treatment with erlotinib when mutation testing is not feasible.     

Favorable clinical course of patients experiencing bevacizumab-induced proteinuria

Nephrotic-range proteinuria, which denotes structural damage to the glomerular filtration barrier, occurs in 1-2% of bevacizumab-treated patients. The glomerular injury and subsequent proteinuria is probably due to a direct targeting of vascular endothelial growth factor (VEGF). We report a case series of six patients who developed a syndrome characterized by proteinuria and hypertension after starting therapy with bevacizumab and who experienced prolonged progression-free survival. Given that altered glomerular permeability appears to be a direct consequence of VEGF inhibition, we hypothesize that proteinuria may indeed correlate with drug efficacy. Optimizing safe and effective drug dosing is critical to achieve the best therapeutic impact due to limited treatment options for many life-threatening advanced cancers. Clinicians should be aware that the development of proteinuria might serve as a surrogate marker of bevacizumab antitumor efficacy and determine the appropriate criteria for withholding this effective anticancer therapy.     

Verb–noun dissociations in relapsing-remitting multiple sclerosis: verb effects of semantic complexity and phonological relatedness

Background: The last two decades have afforded a small but steady rise in the number of studies exposing language dysfunctions in patients with relapsing remitting multiple sclerosis (RRMS), the most common form of multiple sclerosis however, not much is known about word class naming deficits in this group of individuals.

Aim: To explore whether individuals with RRMS show word class naming deficits favouring either nouns or verbs, and if verb accuracy is affected by semantic and phonological verb type.

Method: A total of 31 adults with RRMS were compared to 28 demographically matched healthy controls on noun and verb production using the Greek Object and Action Test (GOAT), a picture-based assessment developed for this purpose. Different semantic categories of verbs were investigated such as conceptually/semantically “heavy” verbs (i.e., instrumental verbs, e.g., “sweeping”) compared to conceptually/semantically “weaker” verbs (i.e., non-instrumental verbs (NIVs), e.g., “sleeping”) and instrumental verbs that were phonologically related to a noun (i.e., name-related instrumental verbs, e.g., “mopping”).

Outcome & results: Verbs were significantly more difficult to retrieve than nouns for the RRMS group on production tasks compared to the demographic and intelligence matched healthy participants. Moreover, there was a significant difference between instrumental and NIV production with instrumental verbs more difficult to retrieve than NIVs. In regard to phonological relatedness, non-name-related instrumental verbs were significantly more difficult to retrieve than name-related instrumental verbs. Multiple regression analyses conducted as a separate model for verbs and nouns indicated that performance on the GOAT could not be explained by any of the predictor variables (demographic, clinical, or neurocognitive performance).

Conclusion: Based on the results, the grammatical distinction for Greek verbs and nouns seems to be preserved in this group of individuals with RRMS. The naming deficit is probably in the connection between the semantic lexicon and the phonological lexicon. In the case of verbs, the magnitude of the difficulty was larger because of the effects of word frequency on verb retrieval. Overall, poor performance on verb and noun naming may be a marker of incipient cognitive decline, and typical cognitive-linguistic testing is not sensitive or specific enough to capture this phenomenon.     

Interferon-alpha Treatment for Disease Control in Metastatic Pheochromocytoma/Paraganglioma Patients

Interferon-alpha (IFN-alpha) is recommended in neuroendocrine tumors (NET). Malignant pheochromocytoma and paragangliomas (MPPGLs) constitute a rare subgroup of NET with few treatment options. IFN-alpha efficacy in patients with MPPGLs was evaluated in a single-center retrospective study. Progression-free survival (PFS) was the primary endpoint according to RECIST 1.1 and/or PERCIST 1.0, and response rate, safety, and symptomatic efficacy were secondary endpoints. Fourteen patients received peginterferon alfa-2a (90 to 180 μg/week) or interferon alfa-2b (1.5 to 3 million units × 3/week) at our institution between December 2005 and February 2014 as the first (n = 7), second (n = 3), or subsequent line (n = 4) of treatment. Most of the patients had a slowly progressive disease before IFN-alpha initiation. Eight patients were men (57%); the median age was 44. At the beginning of treatment, 12 patients had progressive disease demonstrated by FDG-PET (n = 9), MIBG (n = 1), or CT scan (n = 2). Most of the patients treated (64%) had metastatic disease limited to or predominantly located in the bones. During IFN-alpha therapy, bone-directed loco-regional treatments were performed in 9 patients (range 1–4). Median PFS was 17.2 months (95% CI [12.1–58.3]). We observed 3 partial metabolic responses, 9 stable diseases, and 2 progressive diseases. No partial response according to RECIST 1.1 was observed. Symptomatic relief of pain, headaches, diarrhea, or sweating occurred in 6 out of 10 symptomatic pts. Most frequent all grade IFN-α-related toxicities were asthenia (n = 10), lymphopenia (n = 7), thrombopenia (n = 6), and anemia (n = 5). Median overall survival was 7.5 years (95% CI [4–NR]). This study suggests symptomatic response and tumor control effect with interferon-alpha in progressive MPPGLs.     

Prospective Comparison of Freehand and Electromagnetic Needle Tracking for US-guided Percutaneous Liver Biopsy

PurposeTo prospectively compare electromagnetic needle tracking (EMT) and freehand ultrasound (US)-guided liver biopsies.Materials and MethodsAmong 60 consecutive US-guided liver biopsies performed by staff radiologists (senior operators) and residents (junior operators), 30 were performed freehand and 30 with EMT. Needle placement time, numbers of needle punctures and pullbacks, and subjective scores of procedure difficulty were compared by χ² or Student t test.ResultsDiagnostic success rates, defined by the procurement of an adequate histopathologic specimen, were 96.6% for freehand biopsy and 100% with EMT. Needle placement time was significantly lower for EMT (mean ± standard deviation, 45.8 s ± 48.1) than for freehand procedures (143.2 s ± 122.1; P < .01). In the freehand group, needle placement times were 179.6 seconds ± 133.3 for junior operators and 106.8 seconds ± 101.3 for senior operators (P = .15). In the EMT group, needle placement times were 49.2 seconds ± 55 for junior operators and 42.5 seconds ± 41.2 for senior operators (P = .53). The number of needle pullbacks was significantly lower for senior operators (1.2 ± 0.80) compared with junior operators (2.4 ± 1.4) in the freehand group (P = .01), with no significant difference (junior, 0.47 ± 0.92; senior, 0.67 ± 0.72; P = .24) in the EMT group. The postprocedural difficulty score was lower in the EMT group (1.5 ± 0.7) than in the freehand group (2.1 ± 1.1; P = .02). Needle placement time and number of needle pullbacks were lower in the EMT group, even after taking into account tumor size and depth and operator experience.ConclusionsThe EMT procedure shortens needle placement time and reduces the number of needle pullbacks needed for redirection, regardless of operator experience.