AIP and MEN1 mutations and AIP immunohistochemistry in pituitary adenomas in a tertiary referral center

BACKGROUND

Pituitary adenomas have a high disease burden due to tumor growth/invasion and disordered hormonal secretion. Germline mutations in genes such as MEN1 and AIP are associated with early onset of aggressive pituitary adenomas that can be resistant to medical therapy.

AIMS

We performed a retrospective screening study using published risk criteria to assess the frequency of AIP and MEN1 mutations in pituitary adenoma patients in a tertiary referral center.

METHODS

Pituitary adenoma patients with pediatric/adolescent onset, macroadenomas occurring ≤30 years of age, familial isolated pituitary adenoma (FIPA) kindreds and acromegaly or prolactinoma cases that were uncontrolled by medical therapy were studied genetically. We also assessed whether immunohistochemical staining for AIP (AIP-IHC) in somatotropinomas was associated with somatostatin analogs (SSA) response.

RESULTS

Fifty-five patients met the study criteria and underwent genetic screening for AIP/MEN1 mutations. No mutations were identified and large deletions/duplications were ruled out using MLPA. In a cohort of sporadic somatotropinomas, low AIP-IHC tumors were significantly larger (P = 0.002) and were more frequently sparsely granulated (P = 0.046) than high AIP-IHC tumors. No significant relationship between AIP-IHC and SSA responses was seen.

CONCLUSIONS

Germline mutations in AIP/MEN1 in pituitary adenoma patients are rare and the use of general risk criteria did not identify cases in a large tertiary-referral setting. In acromegaly, low AIP-IHC was related to larger tumor size and more frequent sparsely granulated subtype but no relationship with SSA responsiveness was seen. The genetics of pituitary adenomas remains largely unexplained and AIP screening criteria could be significantly refined to focus on large, aggressive tumors in young patients.

[Hereditary diffuse gastric cancer : case serie of 8 patients from a single family and literature review]

Hereditary diffuse gastric cancer is a form of gastric cancer associated, in about 40 % of cases, with a germline mutation of the CDH1 gene. The management of patients with a pathogenic mutation of this gene is based on total prophylactic gastrectomy because, until proven otherwise, endoscopic monitoring is insufficient. We report a series of eight patients with pathogenic CDH1 mutation who underwent total prophylactic gastrectomy in our centre.

Newborn screening for SMA in Southern Belgium

Approval was recently granted for a new treatment for spinal muscular atrophy (SMA). Given that the treatment is effective when administered early and the societal burden of SMA-related disability, the implementation of a newborn screening program is warranted. We describe the stepwise process that led us to launch a newborn screening program for SMA in Southern Belgium. Different political, ethical, and clinical partners were informed about this project and were involved in its governance, as were genetic and screening labs. We developed and validated a newborn screening method to specifically recognize homozygous deletions of exon 7 in the SMN1 gene. Subsequently, a 3-year pilot study has been recently initiated in one Belgian neonatal screening laboratory to cover 17.000 neonates per year. Coverage extension to all of Southern Belgium to screen 55.000 babies each year is underway.

Predictive and prognostic role of peripheral blood eosinophil count in triple-negative and hormone receptor-negative/HER2-positive breast cancer patients undergoing neoadjuvant treatment

In current clinical practices, up to 27% of all breast cancer patients receive neoadjuvant chemotherapy. High pathological complete response rate is frequently associated with tumor-infiltrating lymphocytes. Additionally, circulating immune cells are also often linked to chemotherapy response. We performed a retrospective analysis on a cohort of 112 breast cancer patients (79 triple-negative, 33 hormone receptor-negative/HER2-positive) treated with standard neoadjuvant chemotherapy. Eosinophil and lymphocyte counts were collected from whole blood at baseline and during follow-ups and their associations with pathological complete response, relapse, disease-free and breast cancer-specific survival were analyzed. We observed a higher pathological complete response rate in patients who presented at baseline a relative eosinophil count ≥ 1.5% (55.6%) than in those with a relative eosinophil count < 1.5% (36.2%)(p = 0.04). An improvement in breast cancer-specific survival in patients with high relative eosinophil count (p = 0.05; HR = 0.336; 95% CI = 0.107-1.058) or with high relative lymphocyte count (threshold = 17.5%, p = 0.01; HR = 0.217; 95% CI = 0.060-0.783) were also observed. Upon combining the two parameters into the eosinophil x lymphocyte product with a threshold at 35.8, associations with pathological complete response (p = 0.002), relapse (p = 0.028), disease-free survival (p = 0.012) and breast cancer-specific survival (p = 0.001) were also recorded. In conclusion, the relative eosinophil count and eosinophil x lymphocyte product could be promising, affordable and accessible new biomarkers that are predictive for neoadjuvant chemotherapy response and prognostic for longer survival in triple-negative and hormone receptors-negative/HER2-positive breast cancers. Confirmation of these results in a larger patient population is needed.

Genetic assessment and folate receptor autoantibodies in infantile-onset cerebral folate deficiency (CFD) syndrome

INTRODUCTION

Cerebral folate deficiency (CFD) syndromes are defined as neuro-psychiatric conditions with low CSF folate and attributed to different causes such as autoantibodies against the folate receptor-alpha (FR) protein that can block folate transport across the choroid plexus, FOLR1 gene mutations or mitochondrial disorders. High-dose folinic acid treatment restores many neurologic deficits.

STUDY AIMS AND METHODS

Among 36 patients from 33 families the infantile-onset CFD syndrome was diagnosed based on typical clinical features and low CSF folate. All parents were healthy. Three families had 2 affected siblings, while parents from 4 families were first cousins. We analysed serum FR autoantibodies and the FOLR1 and FOLR2 genes. Among three consanguineous families homozygosity mapping attempted to identify a monogenetic cause. Whole exome sequencing (WES) was performed in the fourth consanguineous family, where two siblings also suffered from polyneuropathy as an atypical finding.

RESULTS

Boys (72%) outnumbered girls (28%). Most patients (89%) had serum FR autoantibodies fluctuating over 5-6 weeks. Two children had a genetic FOLR1 variant without pathological significance. Homozygosity mapping failed to detect a single autosomal recessive gene. WES revealed an autosomal recessive polynucleotide kinase 3´phosphatase (PNKP) gene abnormality in the siblings with polyneuropathy.

DISCUSSION

Infantile-onset CFD was characterized by serum FR autoantibodies as its predominant pathology whereas pathogenic FOLR1 gene mutations were absent. Homozygosity mapping excluded autosomal recessive inheritance of any single responsible gene. WES in one consanguineous family identified a PNKP gene abnormality that explained the polyneuropathy and also its contribution to the infantile CFD syndrome because the PNKP gene plays a dual role in both neurodevelopment and immune-regulatory function. Further research for candidate genes predisposing to FRα-autoimmunity is suggested to include X-chromosomal and non-coding DNA regions.

IκBζ: an emerging player in cancer

IκBζ, an atypical member of the nuclear IκB family of proteins, is expressed at low levels in most resting cells, but is induced upon stimulation of Toll-like/IL-1 receptors through an IRAK1/IRAK4/NFκB-dependent pathway. Like its homolog Bcl3, IκBζ can regulate the transcription of a set of inflamatory genes through its association with the p50 or p52 subunits of NF-κB. Long studied as a key component of the immune response, IκBζ emerges as an important regulator of inflammation, cell proliferation and survival. As a result, growing evidence support the role of this transcription factor in the pathogenesis number of human hematological and solid malignancies.

Innovative methodology for the identification of soluble biomarkers in fresh tissues

The identification of diagnostic and prognostic biomarkers from early lesions, measurable in liquid biopsies remains a major challenge, particularly in oncology. Fresh human material of high quality is required for biomarker discovery but is often not available when it is totally required for clinical pathology investigation. Hence, all OMICs studies are done on residual and less clinically relevant biological samples. Here after, we present an innovative, simple, and non-destructive, procedure named EXPEL that uses rapid, pressure-assisted, interstitial fluid extrusion, preserving the specimen for full routine clinical pathology investigation. In the meantime, the technique allows a comprehensive OMICs analysis (proteins, metabolites, miRNAs and DNA). As proof of concept, we have applied EXPEL on freshly collected human colorectal cancer and liver metastases tissues. We demonstrate that the procedure efficiently allows the extraction, within a few minutes, of a wide variety of biomolecules holding diagnostic and prognostic potential while keeping both tissue morphology and antigenicity unaltered. Our method enables, for the first time, both clinicians and scientists to explore identical clinical material regardless of its origin and size, which has a major positive impact on translation to the clinic.

Variations of circulating cardiac biomarkers during and after anthracycline-containing chemotherapy in breast cancer patients

Background

Over time, the chance of cure after the diagnosis of breast cancer has been increasing, as a consequence of earlier diagnosis, improved diagnostic procedures and more effective treatment options. However, oncologists are concerned by the risk of long term treatment side effects, including congestive heart failure (CHF).

Methods

In this study, we evaluated innovative circulating cardiac biomarkers during and after anthracycline-based neoadjuvant chemotherapy (NAC) in breast cancer patients. Levels of cardiac-specific troponins T (cTnT), N-terminal natriuretic peptides (NT-proBNP), soluble ST2 (sST2) and 10 circulating microRNAs (miRNAs) were measured.

Results

Under chemotherapy, we observed an elevation of cTnT and NT-proBNP levels, but also the upregulation of sST2 and of 4 CHF-related miRNAs (miR-126-3p, miR-199a-3p, miR-423-5p, miR-34a-5p). The elevations of cTnT, NT-proBNP, sST2 and CHF-related miRNAs were poorly correlated, suggesting that these molecules could provide different information.

Conclusions

Circulating miRNA and sST2 are potential biomarkers of the chemotherapy-related cardiac dysfunction (CRCD). Nevertheless, further studies and long-term follow-up are needed in order to evaluate if these new markers may help to predict CRCD and to identify the patients at risk to later develop CHF.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4015-4) contains supplementary material, which is available to authorized users.

Natural Antisense Transcripts: Molecular Mechanisms and Implications in Breast Cancers

Natural antisense transcripts are RNA sequences that can be transcribed from both DNA strands at the same locus but in the opposite direction from the gene transcript. Because strand-specific high-throughput sequencing of the antisense transcriptome has only been available for less than a decade, many natural antisense transcripts were first described as long non-coding RNAs. Although the precise biological roles of natural antisense transcripts are not known yet, an increasing number of studies report their implication in gene expression regulation. Their expression levels are altered in many physiological and pathological conditions, including breast cancers. Among the potential clinical utilities of the natural antisense transcripts, the non-coding|coding transcript pairs are of high interest for treatment. Indeed, these pairs can be targeted by antisense oligonucleotides to specifically tune the expression of the coding-gene. Here, we describe the current knowledge about natural antisense transcripts, their varying molecular mechanisms as gene expression regulators, and their potential as prognostic or predictive biomarkers in breast cancers.

Transcriptome-wide analysis of natural antisense transcripts shows their potential role in breast cancer

Non-coding RNAs (ncRNA) represent 1/5 of the mammalian transcript number, and 90% of the genome length is transcribed. Many ncRNAs play a role in cancer. Among them, non-coding natural antisense transcripts (ncNAT) are RNA sequences that are complementary and overlapping to those of either protein-coding (PCT) or non-coding transcripts. Several ncNATs were described as regulating protein coding gene expression on the same loci, and they are expected to act more frequently in cis compared to other ncRNAs that commonly function in trans. In this work, 22 breast cancers expressing estrogen receptors and their paired adjacent non-malignant tissues were analyzed by strand-specific RNA sequencing. To highlight ncNATs potentially playing a role in protein coding gene regulations that occur in breast cancer, three different data analysis methods were used: differential expression analysis of ncNATs between tumor and non-malignant tissues, differential correlation analysis of paired ncNAT/PCT between tumor and non-malignant tissues, and ncNAT/PCT read count ratio variation between tumor and non-malignant tissues. Each of these methods yielded lists of ncNAT/PCT pairs that were enriched in survival-associated genes. This work highlights ncNAT lists that display potential to affect the expression of protein-coding genes involved in breast cancer pathology.

A novel SMAD3 mutation caused multiple aneurysms in a patient without osteoarthritis symptoms

Heterozygous mutations in the SMAD3 gene were recently described as the cause of a form of non-syndromic familial aortic thoracic aneurysm and dissection (FTAAD) transmitted as an autosomal dominant disorder and often associated with early-onset osteoarthritis. This new clinical entity, called aneurysms-osteoarthritis syndrome (AOS) or Loeys-Dietz syndrome 3 (LDS3), is characterized by aggressive arterial damages such as aneurysms, dissections and tortuosity throughout the arterial tree. We report, here, the case of a 45 year-old man presenting multiple visceral arteries and abdominal aortic aneurysms but without dissection of the thoracic aorta and without any sign of osteoarthritis. Exome-sequencing revealed a new frameshift heterozygous c.455delC (p.Pro152Hisfs*34) mutation in the SMAD3 gene. This deletion is located in the exon 3 coding for the linker region of the protein and causes a premature stop codon at positions 556-558 in the exon 4. The same mutation was found in the proband's mother and sister who had open surgery for abdominal aortic aneurysm and in one of his children who was 5 year-old and did not present aneurysm yet.

Circulating microRNA-based screening tool for breast cancer

Circulating microRNAs (miRNAs) are increasingly recognized as powerful biomarkers in several pathologies, including breast cancer. Here, their plasmatic levels were measured to be used as an alternative screening procedure to mammography for breast cancer diagnosis.

A plasma miRNA profile was determined by RT-qPCR in a cohort of 378 women. A diagnostic model was designed based on the expression of 8 miRNAs measured first in a profiling cohort composed of 41 primary breast cancers and 45 controls, and further validated in diverse cohorts composed of 108 primary breast cancers, 88 controls, 35 breast cancers in remission, 31 metastatic breast cancers and 30 gynecologic tumors.

A receiver operating characteristic curve derived from the 8-miRNA random forest based diagnostic tool exhibited an area under the curve of 0.81. The accuracy of the diagnostic tool remained unchanged considering age and tumor stage. The miRNA signature correctly identified patients with metastatic breast cancer. The use of the classification model on cohorts of patients with breast cancers in remission and with gynecologic cancers yielded prediction distributions similar to that of the control group.

Using a multivariate supervised learning method and a set of 8 circulating miRNAs, we designed an accurate, minimally invasive screening tool for breast cancer.

[A Familial Non Medullary Thyroid Carcinoma (FNMTC) : a clinical and genetic update]

The syndrome of Familial Non Medullary Thyroid Carcinoma (FNMTC) includes two or more patients with an isolated non-medullary thyroid cancer (papillary, follicular, anaplastic) within the same family. To diagnose FNMTC, the clinician must exclude a syndromic presentation such as the syndromes of Cowden, Gardner or Werner, and the Carney Complex. Up to now, a hundred families with FNMTC have been genetically studied, including forms with (Ch19p13.2) or without oxyphilia (Ch2q21), in association with a multinodular goiter (Ch14q32), or with a renal cancer (Ch1q21). Several candidate genes of susceptibility have been proposed: SRGAP1, NKX2-1, FOXE1 and HABP2. So far, it is considered that familial cases represent less than 5 % of thyroid cancers. Although rare, these cases represent a unique opportunity to improve our understanding of thyroid cancer. The identification of candidate genes will enrich our knowledge of thyroid cancer pathophysiology. Based on the literature and our experience of the follow-up of eight families with FNMTC, we discuss epidemiological, clinical, pathological and genetic aspects of FNMTC with a view to improve the diagnosis and treatment of this disease.

Exome copy number variation detection: Use of a pool of unrelated healthy tissue as reference sample

An increasing number of bioinformatic tools designed to detect CNVs (copy number variants) in tumor samples based on paired exome data where a matched healthy tissue constitutes the reference have been published in the recent years. The idea of using a pool of unrelated healthy DNA as reference has previously been formulated but not thoroughly validated. As of today, the gold standard for CNV calling is still aCGH but there is an increasing interest in detecting CNVs by exome sequencing. We propose to design a metric allowing the comparison of two CNV profiles, independently of the technique used and assessed the validity of using a pool of unrelated healthy DNA instead of a matched healthy tissue as reference in exome-based CNV detection. We compared the CNV profiles obtained with three different approaches (aCGH, exome sequencing with a matched healthy tissue as reference, exome sequencing with a pool of eight unrelated healthy tissue as reference) on three multiple myeloma samples. We show that the usual analyses performed to compare CNV profiles (deletion/amplification ratios and CNV size distribution) lack in precision when confronted with low LRR values, as they only consider the binary status of each CNV. We show that the metric-based distance constitutes a more accurate comparison of two CNV profiles. Based on these analyses, we conclude that a reliable picture of CNV alterations in multiple myeloma samples can be obtained from whole-exome sequencing in the absence of a matched healthy sample.

Combined treatment with octreotide LAR and pegvisomant in patients with pituitary gigantism: clinical evaluation and genetic screening

INTRODUCTION

Pituitary gigantism is a rare condition caused by growth hormone secreting hypersecretion, usually by a pituitary tumor. Acromegaly and gigantism cases that have a genetic cause are challenging to treat, due to large tumor size and poor responses to some medical therapies (e.g. AIP mutation affected cases and those with X-linked acrogigantism syndrome).

MATERIALS AND METHODS

We performed a retrospective study to identify gigantism cases among 160 somatotropinoma patients treated between 1985 and 2015 at the University Hospital of Caracas, Venezuela. We studied clinical details at diagnosis, hormonal responses to therapy and undertook targeted genetic testing. Among the 160 cases, eight patients (six males; 75 %) were diagnosed with pituitary gigantism and underwent genetic analysis that included array comparative genome hybridization for Xq26.3 duplications.

RESULTS

All patients had GH secreting pituitary macroadenomas that were difficult to control with conventional treatment options, such as surgery or primary somatostatin receptor ligand (SRL) therapy. Combined therapy (long-acting SRL and pegvisomant) as primary treatment or after pituitary surgery and radiotherapy permitted the normalization of IGF-1 levels and clinical improvement. Novel AIP mutations were the found in three patients. None of the patients had Xq26.3 microduplications.

CONCLUSIONS

Treatment of pituitary gigantism is frequently challenging; delayed control increases the harmful effects of GH excess, such as, excessive stature and symptom burden, so early diagnosis and effective treatment are particularly important in these cases.

[Cancer therapy-induced cardiotoxicity]

The incidence of cancer is raising and the treatments are increasingly aggressive. Consequently, physicians are regularly facing side effects of cytotoxic therapies. Cancer- therapy-induced cardiotoxicity is a serious complication because it can be fatal and causes a temporary or permanent cessation of the treatment. In this article, we summarize the mechanisms, the monitoring and the multidisciplinary management of patients with cancer-therapy induced cardiotoxicity.

New perspective on maintenance therapies for platinum- sensitive recurrent ovarian cancer in women with germline and somatic mutations in BRCA1 and BRCA2 genes

Ovarian cancer (OC) is the seventh most common cancer in women. Although women diagnosed with OC are usually treated frontline with platinum-based chemotherapy, most of them relapse once treatment is halted. Therefore, maintenance therapies have been developed to secure the response and delay further chemotherapy. There are two established maintenance therapies for women affected by platinum-sensitive recurrent OC: bevacizumab, a humanized monoclonal antibody targeting vascular endothelial growth factor, and olaparib, an inhibitor of poly (adenosine diphosphate [ADP]-ribose) polymerase (PARPi). Loss-of-function mutations in genes in the homologous recombination pathway, especially BRCA1 and BRCA2, predict higher rates of platinum sensitivity, better overall survival (OS), and better response to PARPi in women with OC. Among patients with platinum-sensitive recurrent OC, a BRCA mutation is the first genetically defined predictive marker for targeted therapy, since these patients are most likely to benefit from treatment with a PARPi, such as olaparib. In patients with platinum-sensitive recurrent OC without a BRCA mutation, bevacizumab currently seems to be the best maintenance option. Women with OC are progressively more routinely screened for germline BRCA mutations, and the implication of somatic BRCA mutations is increasingly being recognized in OC. Therefore, the recommendations should be updated to reflect the importance of both types of mutations. Together, these data highlight the fact that treatment of recurrent OC can be optimized using genomic contributions to individualize therapy and to improve treatment response.

CXCL12 mediates glioblastoma resistance to radiotherapy in the subventricular zone

BACKGROUND

Patients with glioblastoma (GBM) have an overall median survival of 15 months despite multimodal therapy. These catastrophic survival rates are to be correlated to systematic relapses that might arise from remaining glioblastoma stem cells (GSCs) left behind after surgery. In this line, it has recently been demonstrated that GSCs are able to escape the tumor mass and preferentially colonize the adult subventricular zone (SVZ). At a distance from the initial tumor site, these GSCs might therefore represent a high-quality model of clinical resilience to therapy and cancer relapses as they specifically retain tumor-initiating abilities.

METHOD

While relying on recent findings that have validated the existence of GSCs in the human SVZ, we questioned the role of the SVZ niche as a potential GSC reservoir involved in therapeutic failure.

RESULTS

Our results demonstrate that (i) GSCs located in the SVZ are specifically resistant to radiation in vivo, (ii) these cells display enhanced mesenchymal roots that are known to be associated with cancer radioresistance, (iii) these mesenchymal traits are specifically upregulated by CXCL12 (stromal cell-derived factor-1) both in vitro and in the SVZ environment, (iv) the amount of SVZ-released CXCL12 mediates GBM resistance to radiation in vitro, and (v) interferes with the CXCL12/CXCR4 signalling system, allowing weakening of the tumor mesenchymal roots and radiosensitizing SVZ-nested GBM cells.

CONCLUSION

Together, these data provide evidence on how the adult SVZ environment, through the release of CXCL12, supports GBM therapeutic failure and potential tumor relapse.