Matthieu Talagas

Molecular cytogenetic and genetic aspects of globozoospermia: a review

Infertility is estimated to affect up to 15% of couples of reproductive age. Among the male factors, globozoospermia (also called round‐headed sperm syndrome) is a rare type of teratozoospermia accounting for <0.1% of male infertility. Lack of acrosome, whose production is a postmeiotic event in spermatogenesis, and round sperm head are its main characteristics. The acrosomeless spermatozoon is unable to go through the zona pellucida and fuse with the oolemma of the oocyte, and fertilisation failures have been attributed to a deficiency in oocyte activation capacity, even when intracytoplasmic sperm injection (ICSI) is attempted. The pathogenesis of this anomaly is still unclear but genetic factors are likely to be involved. DNA fragmentation rate has been reported for 16 globozoospermic males, usually using the terminal uridine nick‐end labelling (TUNEL) assay. Most of the patients had a DNA fragmentation index (DFI) higher than that in fertile men. The rate of aneuploidy for some specific chromosomes was increased in 12 among the 26 globozoospermic males reported in the literature. The same results (high DFI and aneuploidy rates) were observed in infertile males compared to fertile men, notably in those with oligoasthenozoospermia or teratozoospermia, independently of the origins. Mutations or deletions in three genes, SPATA16, PICK1 and DPY19L2, have been shown to be responsible for globozoospermia. Proteins coded by the first two genes localise to the Golgi apparatus and the proacrosomal granules that are transported in the acrosome. It is likely that other proteins involved in the acrosome formation remain to be identified.

NRAS Q61R , BRAF V600E immunohistochemistry: a concomitant tool for mutation screening in melanomas

BackgroundThe determination of NRAS and BRAF mutation status is a major requirement in the treatment of patients with metastatic melanoma. Mutation specific antibodies against NRASQ61R and BRAFV600E proteins could offer additional data on tumor heterogeneity. The specificity and sensitivity of NRASQ61R immunohistochemistry have recently been reported excellent. We aimed to determine the utility of immunohistochemistry using SP174 anti-NRASQ61R and VE1 anti-BRAFV600E antibodies in the theranostic mutation screening of melanomas.Methods142 formalin-fixed paraffin-embedded melanoma samples from 79 patients were analyzed using pyrosequencing and immunohistochemistry.Results23 and 26 patients were concluded to have a NRAS-mutated or a BRAF-mutated melanoma respectively. The 23 NRASQ61R and 23 BRAFV600E-mutant samples with pyrosequencing were all positive in immunohistochemistry with SP174 antibody and VE1 antibody respectively, without any false negative. Proportions and intensities of staining were varied. Other NRASQ61L, NRASQ61K, BRAFV600K and BRAFV600R mutants were negative in immunohistochemistry. 6 single cases were immunostained but identified as wild-type using pyrosequencing (1 with SP174 and 5 with VE1). 4/38 patients with multiple samples presented molecular discordant data. Technical limitations are discussed to explain those discrepancies. Anyway we could not rule out real tumor heterogeneity.ConclusionsIn our study, we showed that combining immunohistochemistry analysis targeting NRASQ61R and BRAFV600E proteins with molecular analysis was a reliable theranostic tool to face challenging samples of melanoma.

Dual NRASQ61R and BRAFV600E mutation-specific immunohistochemistry completes molecular screening in melanoma samples in a routine practice

NRAS and BRAF mutational status has become mandatory to treat patients with metastatic melanomas. Mutation-specific immunohistochemistry (IHC) can help analyze challenging tumor samples. We report our experience integrating NRASQ61R (SP174) and BRAFV600E (VE1) IHC in routine practice in a cancer molecular genetic platform. All samples screened for BRAF and NRAS mutations during the year 2014 were analyzed by IHC and pyrosequencing, with an independent analysis of the 2 methods. Cases with first-line discordant results benefited from a complementary second-round IHC and next-generation sequencing (NGS) with a final interpretation taking into account the results of pyrosequencing, IHC, NGS, and quantification of the tumor cells. We analyzed 111 consecutive formalin-fixed and paraffin-embedded melanoma samples from 101 patients. Twenty-two and 11 samples were concordant for BRAFV600E and NRASQ61R mutations, respectively. Second-round analyses of 9 discordant and 1 molecularly inconclusive samples allowed conclusion in 4 further mutated samples (2 BRAFV600E and 2 NRASQ61R). A sample remained NRASQ61R IHC negative but NRASQ61R mutated with molecular methods. Overall, BRAFV600 and NRASQ61 mutation frequencies were 31.7% and 30.7%, respectively. When compared to molecular results, the sensitivity and specificity of IHC were 100% for BRAFV600E IHC and 92.3% and 98.9% for NRASQ61R IHC, respectively. IHC interpretation required a more stringent cutoff for BRAFV600E IHC than NRASQ61R to minimize false results. We conclude that NRASQ61R and BRAFV600E IHC coupled with NGS allow detection of mutations in melanoma challenging samples.

Breast Implant-Associated Anaplastic Large-Cell Lymphoma Can Be a Diagnostic Challenge for Pathologists

Background: Primary anaplastic large-cell lymphoma (ALCL) occurring in women with breast implants is very rare. It is usually described as tumor cells infiltrating the periprosthetic capsule. These are most often revealed by a periprosthetic recurrent isolated effusion (seroma cavity), occurring late after implantation of the prosthesis. ALCL is more rarely a tumor or periprosthetic capsular contracture. Case: We report a 66-year-old woman, initially diagnosed by cytological examination of breast effusion, in whom ALCL appeared two and a half months after the removal of a ruptured implant. Repeated biopsies of the periprosthetic capsule performed in parallel showed fibrous tissue, without tumor proliferation. Only meticulous histological examination of the total capsulectomy identified tumor cells as a thin and discontinuous layer along the inner surface of the capsule without capsular invasion. Conclusion: Awareness of the histological pattern of this new clinical entity is important. A total capsulectomy with a good sampling for microscopic examination should be conducted for any suspicion of breast implant-associated ALCL. Cytology-histology correlation is essential.

What about physical contacts between epidermal keratinocytes and sensory neurons

Recent studies have demonstrated that keratinocytes closely participate in sensory transduction, and therefore, intra‐epidermal free nerve endings are not exclusive transducers of pain. This discovery implies the existence of close afferent communication from keratinocytes to sensory neurons. Although reciprocal interactions between keratinocytes and intra‐epidermal free nerve endings via soluble mediators are well established, little attention has been paid to physical contacts between keratinocytes and intra‐epidermal free nerve endings. This review proposes to consider the ultrastructural and functional knowledge of these contacts, in both human skin biopsies and keratinocyte‐sensory neuron cocultures to speculate on the possible existence of synaptic contacts.

ALK-rearranged squamous cell lung carcinoma responding to crizotinib: A missing link in the field of non-small cell lung cancer?

ALK-rearrangements are mainly encountered in lung adenocarcinomas and allow treating patients with anti-ALK targeted therapy. ALK-rearranged squamous cell lung carcinomas are rare tumors that can also respond to anti-ALK-targeted therapy. Nevertheless, ALK screening is not always performed in patients with squamous cell lung carcinomas making the identification and treatment of this molecular tumor subtype challenging. We intend to report a rare case of ALK-rearranged lung squamous cell carcinoma with response to crizotinib therapy. We report clinical, pathological, immunohistochemical and fluorescent in situ hybridization data concerning a patient having an ALK-rearranged squamous cell lung cancer diagnosed in our institution. The patient was a 58-year old woman with a metastatic-stage lung cancer. Histopathological and immunohistochemical analyses were performed on a bronchial biopsy sample and concluded in a non-keratinizing squamous cell lung carcinoma expressing strongly cytokeratin 5/6, p63 and p40, which are classic hallmarks of lung squamous cell carcinomas, but also cytokeratin 7 which is more commonly expressed in lung adenocarcinomas. The tumor did not express thyroid transcription factor-1. ALK rearrangement was searched because of the never-smoker status of the patient and resulted in strong positive fluorescent in situ hybridization test and ALK/p80 immunohistochemistry. The patient responded to crizotinib therapy during 213 days. Our observation points out the interest of considering ALK screening in patients with metastatic lung squamous cell carcinomas, especially in patients lacking a usual heavy-smoker clinical history. The histopathological and immunohistochemical features of this particular tumor highlighting the overlapping criteria between lung adenocarcinomas and rare ALK-rearranged squamous cell lung carcinomas could also be relevant to extend ALK screening to tumors with intermediate phenotypes between squamous cell carcinomas and adenocarcinomas and/or arising in non-smokers.

Immune effects of the neurotoxins ciguatoxins and brevetoxins

&NA; Ciguatoxins (CTXs) and brevetoxins (PbTxs) are phycotoxins that can accumulate along the marine food chain and thus cause seafood poisoning in humans, namely “ciguatera fish poisoning” (CFP) and “neurotoxic shellfish poisoning” (NSP), respectively. CFP is characterized by early gastrointestinal symptoms and typical sensory disorders (paraesthesia, pain, pruritus and cold dysaesthesia), which can persist several weeks and, in some cases, several months or years. NSP is considered a mild form of CFP with similar but less severe symptoms. After inhaled exposure, PbTxs can also cause respiratory tract irritation in healthy subjects and asthma exacerbations in predisposed subjects, whose respiratory functions may be disrupted for several days following PbTx inhalation. Mechanistically, it is well established that CTX‐ or PbTx‐induced disturbances are primarily mainly due to voltage‐gated sodium channel activation in sensory and motor peripheral nervous system. However, little is known about the pathophysiology or a potential individual susceptibility to long lasting effects of CFP/NSP. In addition to their action on the nervous system, PbTxs and CTXs were also shown to exert effects on the immune system. However, their role in the pathophysiology of syndromes induced by CTX or PbTx exposure is poorly documented. The aim of this review is to inventory the literature thus far on the inflammatory and immune effects of PbTxs and CTXs. HighlightsMast cells contribute to the PbTx‐induced bronchoconstriction in allergic models.PbTxs have been shown to impair humoral competence, inhibit cathepsin activity, and modulate lymphocyte proliferation.There is in vitro evidence of the ability of CTXs to activate macrophages.Acute exposure to CTXs triggers a systemic immune response that is rather an anti‐inflammatory Th2 response.Some MHC variants could predispose to development of persistent ciguatera syndrome.

Innervation of the Male Breast: Psychological and Physiological Consequences

Breasts, including the nipple and areola, have two functions: lactation and as an erogenous area. Male breasts are much less studied that those of women. In men, breasts have only an erotic function. Because there is dense and very well organized innervation of the nipple-areola complex in men, nipple erection occurs frequently and via different mechanisms from penile erection. Although it seems to be less important for men than for women and it is poorly studied, the erotic value of breast stimulation is notable. Consequently, there is a need to include this aspect in sexological and andrological studies and to preserve breasts and their innervation or to reconstruct them in cases of surgical intervention.

Fluorescence in situ hybridization testing of chromosomes 6, 8, 9 and 11 in melanocytic tumors is difficult to automate and reveals tumor heterogeneity in melanomas

Malignant melanomas may be difficult to differentiate from benign nevi on the basis of histology. Contrary to nevi, the majority of melanomas harbor chromosomal imbalances. Comparative genomic hybridization-based and fluorescence in situ hybridization (FISH) tests can help differentiating malignant from benign tumors. In the present study, eight-bacterial artificial chromosome (BAC) probes targeting chromosomes 6, 8, 9 and 11 were tested by FISH, and compared with a commercial four-color FISH probe set targeting chromosomes 6 and 11 in a first set of 62 tissue microarray-included melanocytic tumors (47 melanomas and 15 nevi). A second set of 108 tumors (70 melanomas and 38 nevi) was analyzed with the eight-probes kit, and manual counting was compared with the newly developed automated FISH signals counting and with semi-quantitative visual detection of chromosomal imbalances. Intra-tumor heterogeneity was also evaluated in 12 melanomas and 10 patients with paired melanoma samples. Testing the tumors from the first set with the commercial kit and the eight-probes test permitted to correctly identify 45/47 and 47/47 melanomas, respectively. In the second tumor set, 65/70 malignant tumors presented at least one chromosomal imbalance, whereas none was detected in the nevi. The agreement between manual and automated signals counting was better in good-quality FISH slides compared with poor-quality slides. Semi-quantitative visual appreciation of chromosomal imbalances also reached strong agreement with exact manual counting. In addition, a frequent cytogenetic heterogeneity within melanomas and between paired tumors was noticed in patients with metastatic melanomas. To conclude, FISH testing targeting chromosomes 6, 8, 9 and 11 enabled to differentiate the majority of melanomas from nevi but was difficult to automate. Tumor cytogenetic heterogeneity was frequent and could impair FISH testing.

Duplication of SOX3 (Xq27) may be a risk factor for Neural Tube Defects

Duplication of SOX3 (Xq27) may be a Risk Factor For Neural Tube Defects Arnaud Uguen,* Matthieu Talagas, Sylvia Qu emener-Redon, Pascale Marcorelles, and Marc De Braekeleer Inserm, U1078, Brest F-29200, France CHRU Brest, Service d’anatomie et cytologie pathologiques, Brest F-29220, France Universit e Europ eenne de Bretagne, France Facult e de M edecine et des Sciences de la Sant e Universit e de Brest, EA4685, Brest F-29200, France CHRU Brest, Laboratoire de G en etique Mol eculaire et d’Histocompatibilit e, Brest F-29220, France CHRU Brest, Laboratoire de Cytog en etique et Biologie de la Reproduction, Brest F-29220, France