High mesothelin expression in advanced lung adenocarcinoma is associated with KRAS mutations and a poor prognosis

Mesothelin is a cell surface glycoprotein which is highly expressed in several epithelial cancers and may have a role in cell adhesion and metastases. In this study, we used prospectively obtained clinical and pathological data to characterize mesothelin expression in advanced lung adenocarcinoma. Tissue was obtained from patients who underwent molecular profiling of potentially actionable genes on a trial of molecular profiling and targeted therapies in advanced thoracic malignancies. We immunohistochemically evaluated the intensity, and the percentage of cells expressing mesothelin in 93 advanced lung adenocarcinomas. The evaluation was blinded for molecular data and outcome. Mutations of EGFR, KRAS, BRAF, AKT1, PIK3CA and HER2 were assessed by pyrosequencing; HER2 amplification and ALK translocation were assessed by fluorescence in situ hybridization. 53% of advanced lung adenocarcinomas expressed mesothelin to some degree; high mesothelin expression, defined as mesothelin positivity in more than 25% of cells, was found in 24% of patients. High mesothelin expression was associated with inferior survival (median 18.2 months vs. 32.9 months; P = 0.014). High mesothelin expression was strongly associated with mutant KRAS (P < 0.0001) and wild-type EGFR (P = 0.002). Our results provide strong rationale to explore anti-mesothelin targeted therapies in advanced lung adenocarcinoma especially in the KRAS-mutant subgroup.     

Phospho-TCTP as a therapeutic target of dihydroartemisinin for aggressive breast cancer cells

Upregulation of Translationally Controlled Tumor Protein (TCTP) is associated with poorly differentiated aggressive tumors, including breast cancer, but the underlying mechanism(s) are still debated. Here, we show that in breast cancer cell lines TCTP is primarily localized in the nucleus, mostly in the phosphorylated form.The effects of Dihydroartemisinin (DHA), an anti-malaria agent that binds TCTP, were tested on breast cancer cells. DHA decreases cell proliferation and induces apoptotic cell death by targeting the phosphorylated form of TCTP. Remarkably, DHA enhances the anti-tumor effects of Doxorubicin in triple negative breast cancer cells resulting in an increased level of apoptosis. DHA also synergizes with Trastuzumab, used to treat HER2/neu positive breast cancers, to induce apoptosis of tumor cells.Finally, we present new clinical data that nuclear phospho-TCTP overexpression in primary breast cancer tissue is associated with high histological grade, increase expression of Ki-67 and with ER-negative breast cancer subtypes. Notably, phospho-TCTP expression levels increase in trastuzumab-resistant breast tumors, suggesting a possible role of phospho-TCTP as a new prognostic marker.In conclusion, the anti-tumor effect of DHA in vitro with conventional chemotherapeutics suggests a novel therapeutic strategy and identifies phospho-TCTP as a new promising target for advanced breast cancer.     

Gene expression profile predictive of response to chemotherapy in metastatic colorectal cancer

Fluoropyrimidine-based chemotherapy (CT) has been the mainstay of care of metastatic colorectal cancer (mCRC) for years. Response rates are only observed, however, in about half of treated patients, and there are no reliable tools to prospectively identify patients more likely to benefit from therapy. The purpose of our study was to identify a gene expression profile predictive of CT response in mCRC. Whole genome expression analyses (Affymetrix GeneChip^® HG-U133 Plus 2.0) were performed in fresh frozen tumor samples of 37 mCRC patients (training cohort). Differential gene expression profiles among the two study conditions (responders versus non-responders) were assessed using supervised class prediction algorithms. A set of 161 differentially expressed genes in responders (23 patients; 62%) versus non-responders (14 patients; 38%) was selected for further assessment and validation by RT-qPCR (TaqMan^®Low Density Arrays (TLDA) 7900 HT Micro Fluidic Cards) in an independent multi-institutional cohort (53 mCRC patients). Seven of these genes were confirmed as significant predictors of response. Patients with a favorable predictive signature had significantly greater response rate (58% vs 13%, p = 0.024), progression-free survival (61% vs 13% at 1 year, HR = 0.32, p = 0.009) and overall survival (32 vs 16 months, HR = 0.21, p = 0.003) than patients with an unfavorable gene signature. This is the first study to validate a gene-expression profile predictive of response to CT in mCRC patients. Larger and prospective confirmatory studies are required, however, in order to successfully provide oncologists with adequate tools to optimize treatment selection in routine clinical practice.     

Truncated RAF kinases drive resistance to MET inhibition in MET-addicted cancer cells

Constitutively active receptor tyrosine kinases (RTKs) are known oncogenic drivers and provide valuable therapeutic targets in many cancer types. However, clinical efficacy of RTK inhibitors is limited by intrinsic and acquired resistance. To identify genes conferring resistance to inhibition of the MET RTK, we conducted a forward genetics screen in the GTL-16 gastric cancer cell line, carrying MET amplification and exquisitely sensitive to MET inhibition. Cells were transduced with three different retroviral cDNA expression libraries and selected for growth in the presence of the MET inhibitor PHA-665752. Selected cells displayed robust and reproducible enrichment of library-derived cDNAs encoding truncated forms of RAF1 and BRAF proteins, whose silencing reversed the resistant phenotype. Transduction of naïve GTL-16 cells with truncated, but not full length, RAF1 and BRAF conferred in vitro and in vivo resistance to MET inhibitors, which could be reversed by MEK inhibition. Induction of resistance by truncated RAFs was confirmed in other MET-addicted cell lines, and further extended to EGFR-addicted cells. These data show that truncated RAF1 and BRAF proteins, recently described as products of genomic rearrangements in gastric cancer and other malignancies, have the ability to render neoplastic cells resistant to RTK-targeted therapy.     

Monosomy of chromosome 17 in breast cancer during interpretation of HER2 gene amplification

Monosomy of chromosome 17 may affect the assessment of HER2 amplification. Notably, the prevalence ranges from 1% up to 49% due to lack of consensus in recognition. We sought to investigate the impact of monosomy of chromosome 17 to interpretation of HER2 gene status. 201 breast carcinoma were reviewed for HER2 gene amplification and chromosome 17 status. FISH analysis was performed by using double probes (LSI/CEP). Absolute gene copy number was also scored per each probe. HER2 FISH test was repeated on serial tissue sections, ranging in thickness from 3 to 20 µm. Ratio was scored and subsequently corrected by monosomy after gold control test using the aCGH method to overcome false interpretation due to artefactual nuclear truncation. HER2 immunotests was performed on all cases. 26/201 cases were amplified (13%). Single signals per CEP17 were revealed in 7/201 (3.5%) cases. Five out of 7 cases appeared monosomic with aCGH (overall, 5/201, 2.5%) and evidenced single signals in >60% of nuclei after second-look on FISH when matching both techniques. Among 5, one case showed amplification with a pattern 7/1 (HER2/CEP17>2) of copies (3+ at immunotest); three cases revealed single signals per both probes (LSI/CEP=1) and one case revealed a 3:1 ratio; all last 4 cases showed 0/1+ immunoscore. We concluded that: 1) monosomy of chromosome 17 may be observed in 2.5% of breast carcinoma; 2) monosomy of chromosome 17 due to biological reasons rather than nuclear truncation was observed when using the cut-off of 60% of nuclei harboring single signals; 3) the skewing of the ratio due to single centromeric 17 probe may lead to false positive evaluation; 4) breast carcinomas showing a 3:1 ratio (HER2/CEP17) usually show negative 0/1+ immunoscore and <6 gene copy number at FISH.     

Nasal ciliary motility: a new tool in estimating the time of death

Determination of time since death is one of the most difficult and crucial issue in forensic medicine. Apart from body cooling, which is commonly used in the early postmortem interval (PMI), supravital reactions are the most interesting postmortem changes for time of death estimation. Nasal ciliary motility has been occasionally observed in postmortem period although no studies have focused on this phenomenon for forensic purposes. We aimed to evaluate the diagnostic usefulness of ciliary motility as a potential tool in estimating the time of death. Specimens of ciliated epithelium from 100 consecutive cadavers were obtained by scraping the nasal mucosa at three different postmortem intervals. The samples were then smeared on a slide, and an in vitro evaluation of ciliary movement was analyzed by phase-contrast microscopy. A postmortem nasal ciliary motility was observed, and a statistically significant relationship between decreasing ciliary movements and increasing postmortem interval was detected even in presence of putrefactive changes of nasal ultrastructure integrity. Some peculiar causes of death seem to influence ciliary motility in the early PMI, while no significant correlations with sex or age were observed. According to the results of this study, postmortem evaluation of nasal ciliary motility may be a bona fide and a feasible option for estimating the time of death.     

Grasping with tools: corticospinal excitability reflects observed hand movements

Although facilitation of the corticospinal system during action observation is widely accepted, it remains controversial whether this facilitation reflects a replica of the observed movements or the goal of the observed motor acts. In the present study, we asked whether, when an object is grasped by using a tool, corticospinal facilitation represents 1) the movements of the hand, 2) the movements of the tool, or 3) the distal goal of the action. To address this question, we recorded motor-evoked potentials (MEPs) to transcranial magnetic stimulation while participants observed a hand reaching and grasping a mothball by using 3 types of pliers, requiring different hand-tool movements to achieve the same goal (grasping the object). We found that MEPs recorded from the opponens pollicis and from the first dorsal interosseous reflected the observed hand movements rather than the movements of the tool or the distal goal of the action. These results suggest that during observation of tool actions, detailed motor matching recruits online the same muscles as those used in the observed action.     

Distinct neural substrates for semantic knowledge and naming in the temporoparietal network

Patients with anterior temporal lobe (ATL) lesions show semantic and lexical retrieval deficits, and the differential role of this area in the 2 processes is debated. Functional neuroimaging in healthy individuals has not clarified the matter because semantic and lexical processes usually occur simultaneously and automatically. Furthermore, the ATL is a region challenging for functional magnetic resonance imaging (fMRI) due to susceptibility artifacts, especially at high fields. In this study, we established an optimized ATL-sensitive fMRI acquisition protocol at 4 T and applied an event-related paradigm to study the identification (i.e., association of semantic biographical information) of celebrities, with and without the ability to retrieve their proper names. While semantic processing reliably activated the ATL, only more posterior areas in the left temporal and temporal-parietal junction were significantly modulated by covert lexical retrieval. These results suggest that within a temporoparietal network, the ATL is relatively more important for semantic processing, and posterior language regions are relatively more important for lexical retrieval.     

Primary breast cancer of the vulva: a case report

The occurrence of primary breast cancer of the vulva is extremely rare (24 cases described in the English-language literature). We report a case of a primary breast carcinoma of the vulva. An 82-year-old woman presented with a nodule of the left labia minor, which was excised. The histologic examination revealed the presence of adenocarcinoma of mammary origin, positive for common breast markers and for estrogen and progesterone receptors. The study for orthotopic breast carcinoma was negative, as well as the study for metastatic disease. The diagnosis of primary breast carcinoma was established. Our patient was then submitted to pelvic and inguinal radiotherapy as well as an aromatase inhibitor (letrozole), and she remained completely asymptomatic. Because of the rarity of this condition, guidelines for therapy are unavailable. The management suggested in the literature is that of primary orthotopic breast neoplasm of a similar stage.