Pilar Blay

Protein Kinase C θ Is Highly Expressed in Gastrointestinal Stromal Tumors But Not in Other Mesenchymal Neoplasias

Purpose: Gastrointestinal stromal tumors (GIST) are a distinctive group of mesenchymal neoplasms of the gastrointestinal tract. The oncogene KIT has a central role in the pathogenesis of GIST, with c-kit receptor tyrosine kinase (KIT) protein expression being the gold standard in its diagnosis. The identification of GIST patients has become crucial, because the tyrosine kinase inhibitor Imatinib is effective in the treatment of this malignancy. However, a small set of GISTs remain unrecognized, because KIT protein expression is not always evident. The aim of this study was the identification of new markers for the differential diagnosis of GIST. Experimental Design: By analyzing publicly available data from transcriptional profiling of sarcomas, we found that protein kinase C θ (PKC-θ), a novel PKC isotype involved in T-cell activation, is highly and specifically expressed in GIST. PKC-θ expression in GIST was confirmed by reverse transcription-PCR and Western blot. PKC-θ was analyzed by immunohistochemistry in a panel of 26 GIST, 12 non-GIST soft-tissue sarcomas, and 35 tumors from other histologies. Results: We found that all of the GISTs expressed PKC-θ, whereas this protein was undetectable in other mesenchymal or epithelial tumors, including non-GIST KIT-positive tumors. PKC-θ immunoreactivity was also observed in interstitial cells of Cajal. Conclusions: Our results show that PKC-θ is easily detected by immunohistochemistry in GIST specimens and that it could be a sensitive and specific marker for the diagnosis of this malignancy.

Mutational analysis of BRCA1 and BRCA2 in hereditary breast and ovarian cancer families from Asturias (Northern Spain)

BackgroundThe prevalence of BRCA1 and BRCA2 mutations in Spain is heterogeneous and varies according to geographical origin of studied families. The contribution of these mutations to hereditary breast and ovarian cancer has not been previously investigated in Asturian populations (Northern Spain).MethodsIn the present work, 256 unrelated high-risk probands with breast and/or ovarian cancer from families living in Asturias were analyzed for the presence of a BRCA1 or BRCA2 gene mutation from October 2007 to May 2012. The entire coding sequences and each intron/exon boundaries of BRCA1/2 genes were screened both by direct sequencing and Multiplex Ligation-dependent Probe Amplification (MLPA).ResultsA total of 59 families (23%) were found to carry a pathogenic germ line mutation, 39 in BRCA1 and 20 in BRCA2. Twenty nine additional families (12%) carried an unknown significance variant. We detected 28 distinct pathogenic mutations (16 in BRCA1 and 12 in BRCA2), of which 3 mutations in BRCA1 (c.1674delA, c.1965C>A and c.2900_2901dupCT) and 5 in BRCA2 (c.262_263delCT, c.2095C>T, c.3263dupC, c.4030_4035delinsC, c.8042_8043delCA) had not been previously described.The novel mutations c.2900_2901dupCT in BRCA1 and c.4030_4035delinsC in BRCA2 occurred in 8 and 6 families respectively and clustered in two separated small geographically isolated areas suggesting a founder effect. These 2 mutations, together with the Galician BRCA1 mutation c.211A>G (9 families), and the common BRCA1 mutation c.3331_3334delCAAG (6 families), account for approximately 50% of all affected families. By contrast, very frequent mutations in other Spanish series such as the BRCA1 Ashkenazi founder mutation c.68_69delAG, was found in only one family.ConclusionsIn this study we report the BRCA1 and BRCA2 spectrum of mutations and their geographical distribution in Asturias, which largely differ from other areas of Spain. Our findings may help design a first step recurrent mutation panel for screening high-risk breast and/or ovarian cancer families from this specific area.

Germ-line mutations in epidermal growth factor receptor (EGFR) are rare but may contribute to oncogenesis: A novel germ-line mutation in EGFR detected in a patient with lung adenocarcinoma

BackgroundA subset of lung cancer patients harbour EGFR somatic mutations in their tumours and are candidates for treatment with EGFR tyrosine kinase inhibitors. In a few cases EGFR mutations have also been found in the germ line, suggesting a role in lung carcinogenesis. Objetives of this study were: 1) To analyze the EGFR gene mutations in a population diagnosed with lung adenocarcinoma from Northern Spain. 2) To determine the frequency of a new germ-line mutation found in our laboratory as well as the frequency in our population of three other EGFR germ-line mutations detected by other authors. 3) To determine whether the novel mutation detected may have a functional effect on the EGFR protein.MethodsTumour DNA samples were obtained from frozen or paraffin embedded tumour tissues. Samples of DNA from peripheral blood cells were obtained from 912 individuals with lung cancer recruited from the CAPUA study [1, 2], 477 unrelated healthy donor individuals and 32 individuals with other types of cancer. EGFR gene exons 18 to 21 were studied by direct standard dideoxy sequencing. Specific mutations were determined either by direct sequencing or by specific RFLP analysis. Cell lines were transfected with EGFR-mutant plasmids and analysed by western blot with antibodies specific for total or phosphorylated-EGFR.ResultsWe found EGFR mutation in 12 of the 71 tumour samples (17%). One tumour contained two mutations. One mutation (p.R776G) was present as a germ line. Using an RFLP analysis, this mutation was not found in 954 alleles from healthy individuals studied, concluding that it is not a polymorphism. The mutation was not found either in genomic DNA from 912 lung cancer patients. Three additional EGFR germ-line mutations that were already described were not found in any of the studied samples. These observations show that EGFR mutated alleles are rare in the population. In vitro studies revealed that tyrosine autophosphorylation is enhanced in p.R776G-mutant EGFR when compared with wild-type EGFR. This enhanced autophosphorylation in the absence of ligand may be associated with a proliferative advantage.ConclusionsGerm-line mutations in EGFR are rare but may contribute to oncogenesis

Pegylated Liposomal Doxorubicin and Gemcitabine in a Fixed Dose Rate Infusion for the Treatment of Patients With Poor Prognosis of Recurrent Ovarian Cancer: A Phase Ib Study

Introduction Pegylated liposomal doxorubicin (PLD) is currently the reference treatment for platinum-resistant ovarian cancer. The combination of PLD and gemcitabine and the administration of gemcitabine at a fixed dose rate infusion (FDRI) seem to have additive activity in this disease setting. We have launched a phase Ib study with the combination of FDRI gemcitabine followed by PLD in recurrent ovarian cancer with a platinum-free interval of less than 1 year, with parallel pharmacokinetic and pharmacogenetic studies. Methods The starting dose of gemcitabine was 1500 mg/m2, 10 mg/m2 per minute, every 2 weeks (±250 mg gemcitabine titration depending on toxicity), followed by PLD 35 mg/m2 every 4 weeks. Gemcitabine pharmacokinetics and equilibrative nucleoside transporter 1, deoxycytidine kinase, and ribonucleotide reductase M1 gene expression levels were studied. Results Thirty-five patients were treated at 3 different dose levels (DL). Dose level 1 was not tolerated. Nonfrail patients continued to be treated at DL-1 (G 1250 mg/m2 on day 1 and PLD 35 mg/m2 on days 1 and 15). Of 10 evaluable nonfrail patients, 4 displayed dose-limiting toxicity. Frail patients were treated at DL-2 (G 1250 mg/m2 on day 1 and PLD 35 mg/m2 on days 1 and 15). Of the 12 evaluable frail patients, 3 developed dose-limiting toxicity. Neutropenia, palmar-plantar erythrodysesthesia and stomatitis were the most common toxicities. The response rate was 42.8% (95% confidence interval [CI], 34.5%-51.1%), with 17.1% (6/35) complete responses and 25.7% (9/35) partial responses. The median progression-free survival was 7.7 months (95% CI, 2.2-13.1). The median overall survival was 13.9 months (95% CI, 9.4-18.4). The administration of PLD after gemcitabine did not influence gemcitabine pharmacokinetics or its metabolites. The addition of PLD to gemcitabine caused a larger and longer induction of the ribonucleotide reductase M1 gene. Patients with higher baseline levels of deoxycytidine kinase had longer progression-free survival. Conclusion The recommended dose for a phase II study of patients with recurrent ovarian cancer having poor prognosis is PLD, 35 mg/m2 on day 1, and gemcitabine, 1000 mg/m2 on days 1 and 15 delivered at an FDRI of 10 mg/m2 per minute in 28-day cycles.

Resultados oncológicos y funcionales del tratamiento no quirúrgico comparado con el quirúrgico en los carcinomas epidermoides de orofaringe

INTRODUCTION AND OBJECTIVES Squamous cell carcinomas of the oropharynx are aggressive tumours usually diagnosed at advanced stage. Their optimal treatment has not been established. The aim of this study was to compare the oncological and functional outcomes in patients with carcinomas of the oropharynx treated by radiotherapy (with chemotherapy in advanced stages) vs surgery (with radiotherapy in advanced stages). METHODS A retrospective study on 50 patients with squamous cell cancer of the oropharynx treated by radiotherapy (with or without chemotherapy) at our institution between 1998 and 2008 was carried out. The oncological and functional results were compared with patients with same cancer location and stage treated by surgery (with or without radiotherapy). In both groups, the patients were classified as follows: 10% Stage I, 12% Stage II, 16% Stage III, 48% Stage IVa and 14% Stage IVb. RESULTS The 5-year disease-specific survival was 33% in the radiotherapy group and 52% in the surgical group (P=.17). Five-year disease-specific survival for Stage I and II patients was 82% in the radiotherapy group and 70% in the surgical group. In Stage III and IV disease, 5-year disease-specific survival was higher in the surgical group (47% vs 17%). The functional results were similar; anatomical and functional preservation of the larynx was higher in the radiotherapy group but the successful return to oral food intake was higher in the surgical group. CONCLUSIONS The prognosis of squamous cell carcinoma of the oropharynx is poor. Oncological results in Stages I and II were similar for radiotherapy and surgical treatments. In advanced stages, the prognosis was better in patients treated by surgery with or without radiotherapy. Functional results were similar in both treatment modalities.

Identification of somatic and germ-line DICER1 mutations in pleuropulmonary blastoma, cystic nephroma and rhabdomyosarcoma tumors within a DICER1 syndrome pedigree

BackgroundDICER1 syndrome is a pediatric cancer predisposition condition causing a variety of tumor types in children and young adults. In this report we studied a family with two relatives presenting a variety of neoplastic conditions at childhood.MethodsGerm-line mutation screening of the complete coding region of the DICER1 gene in genomic DNA from the proband was performed. The presence of somatic DICER1 mutation and further alterations in driver genes was investigated in genomic DNA obtained from available tumor samples.ResultsA nonsense germ-line mutation in DICER1 causing a truncated protein at the IIIb domain level was identified segregating within a family including two affected relatives who developed in one case cystic nephroma and pleuropulmonary blastoma, and rhabdomyosarcoma and multinodular goiter in the other. Additional in trans DICER1 missense somatic mutations in the IIIb DICER1 domain were found both in the cystic nephroma and in the rhabdomyosarcoma, suggesting that neoplasms in this family might arise from the unusual two-hit mechanism for DICER-derived tumorigenesis in which after the presence of a truncated constitutive protein, a neomorphic DICER1 activity is somatically adquired. Additional genetic alterations, such as TP53 mutations, were identified in the rhabdomyosarcoma.ConclusionsBesides DICER1 loss of standard activity, oncogenic cooperation of other genes, as mutated TP53, may involve developing higher grade tumors within this syndrome. Given the broad clinical spectrum that may arise, genetic counseling and close surveillance must be offered to all family members at risk of DICER1 syndrome.

Impact of the incorporation of tyrosine kinase inhibitor agents on the treatment of patients with a diagnosis of advanced renal cell carcinoma: study based on experience at the Hospital Universitario Central de Asturias.

IntroductionFor nearly the past two decades, cytokines (CKs) have been the only systemic treatment option available for advanced renal cell carcinoma (RCC). In recent years, tyrosine kinase inhibitors (TKIs) have demonstrated clinical activity on this tumour. Our purpose is to describe one centre’s experience with the use of CKs and TKIs in the treatment of patients with advanced RCC.Materials and methodsThis study was designed as a retrospective chart review of RCC patients who were treated with CKs and/or TKIs in our department between July 1996 and June 2008. Efficacy and toxicity were assessed using World Health Organization (WHO) criteria. The Kaplan-Meier method was used to estimate progression-free (PFS) and overall (OS) survival.ResultsNinety-four patients were classified into three groups depending on the modality of treatment administered: 46 were treated with CKs alone and/or chemotherapy (27 with immunotherapy, one with chemotherapy and 18 with both), 28 with TKIs alone (25 with sunitinib and 13 with sorafenib) and 20 with TKIs in second-line treatment following failure with CKs (17 with sunitinib, eight with sorafenib, four with bevacizumab and one with lapatinib). The median age was 60 years in the CK group and 65 and 62, respectively, in TKI in first and second-line treatment groups. Eighty-five percent of patients treated with CKs and 75% in the TKI group in first-line treatment and 80% in second-line treatment were men. Overall, 89% of patients had favourable risk, and 11% had intermediate risk. All patients were considered evaluable for toxicity. The main grade 3–4 (%) toxicity was asthenia for both groups, (ten in TKIs and 15 in CKs). Other grade 1–2 toxicities were mucositis (39), bleeding (8), hypertension (19), skin toxicity (33) and hypothyroidism (12.5) associated with TKIs; and anaemia (33), cough (29), asthenia (39) and emesis (14) associated with CKs. The objective response rate among 80 patients evaluable for activity was 10.6% with CKs and 46.5% and 35%, respectively, with TKIs in first- and second-line treatments. Disease stabilisation with CKs was recorded at 59% of patients and with TKIs 25% and 50% in first- and second-line treatment groups, respectively. The median progression-free survival (PFS) with CKs was 122 days [95% confidence interval (CI) 82–162] and with TKIs 201 days (65–337) in the firstand 346 days (256–436) in second-line treatment groups. The median overall survival (OS) was 229 days (142–316) and 2,074 days (1,152–2,996) for patients treated with CKs and TKIs.ConclusionsOur results are in line with the activity and survival rates previously reported in the literature regarding the use of TKIs for patients with advanced RCC in first- and second-line treatment, which has demonstrated an acceptable toxicity level.

Tratamiento adyuvante en pacientes diagnosticados de carcinoma no microcítico de pulmón: estado de la evidencia científica

Surgery is the current treatment of choice in patients with early-stage non-small cell lung cancer. Based on the high rates of recurrence, additional local and systemic treatments have been developed, aimed at improving the cure rates. The comparative studies about the benefits of post-operative adjuvant chemotherapy and/or radiotherapy, and the meta-analysis studies made during the last decades, reviewed in some articles appeared in 95 and 97, did not confirm a significant improvement of the overall survival. Since then, new comparative trials carried out with a higher number of patients and with more active and standard chemotherapy seem to show a benefit of the administration of platinum-based chemotherapy, although it has not gained general acceptance. More recently, a new meta-analysis, that included the previous studies, has confirmed an overall increase of 4 % in survival of patients treated by surgery and adjuvant chemotherapy, especially in stages II-III patients receiving schedules of cisplatin and vinorelbine. Further studies are needed to determine the real therapeutic value of other agents, as uracil-tegafur and radiotherapy.