Low MAD2 expression levels associate with reduced progression-free survival in patients with high-grade serous epithelial ovarian cancer.

Epithelial ovarian cancer (EOC) has an innate susceptibility to become chemoresistant. Up to 30% of patients do not respond to conventional chemotherapy [paclitaxel (Taxol®) in combination with carboplatin] and, of those who have an initial response, many patients relapse. Therefore, an understanding of the molecular mechanisms that regulate cellular chemotherapeutic responses in EOC cells has the potential to impact significantly on patient outcome. The mitotic arrest deficiency protein 2 (MAD2), is a centrally important mediator of the cellular response to paclitaxel. MAD2 immunohistochemical analysis was performed on 82 high-grade serous EOC samples. A multivariate Cox regression analysis of nuclear MAD2 IHC intensity adjusting for stage, tumour grade and optimum surgical debulking revealed that low MAD2 IHC staining intensity was significantly associated with reduced progression-free survival (PFS) (p = 0.0003), with a hazard ratio of 4.689. The in vitro analyses of five ovarian cancer cell lines demonstrated that cells with low MAD2 expression were less sensitive to paclitaxel. Furthermore, paclitaxel-induced activation of the spindle assembly checkpoint (SAC) and apoptotic cell death was abrogated in cells transfected with MAD2 siRNA. In silico analysis identified a miR-433 binding domain in the MAD2 3' UTR, which was verified in a series of experiments. Firstly, MAD2 protein expression levels were down-regulated in pre-miR-433 transfected A2780 cells. Secondly, pre-miR-433 suppressed the activity of a reporter construct containing the 3'-UTR of MAD2. Thirdly, blocking miR-433 binding to the MAD2 3' UTR protected MAD2 from miR-433 induced protein down-regulation. Importantly, reduced MAD2 protein expression in pre-miR-433-transfected A2780 cells rendered these cells less sensitive to paclitaxel. In conclusion, loss of MAD2 protein expression results in increased resistance to paclitaxel in EOC cells. Measuring MAD2 IHC staining intensity may predict paclitaxel responses in women presenting with high-grade serous EOC.

Impact of COVID-19 on small biopsy diagnostic procedures and cancer resection surgeries in the North-West of Ireland.

AIMS: To quantify the impact of COVID-19 on small biopsy procedures and cancer resection surgeries in the North-West of Ireland. METHODS: Data was obtained from the Histopathology Departments of University Hospital Galway (UHG) and Letterkenny University Hospital (LUH) Laboratory Information Systems to establish the impact of COVID-19 on both the small biopsy (coded P01) and cancer resection (coded P03) caseloads reported from January to June 2020, with comparison made to January to June 2019. RESULTS: From January to June 2020 compared with January to June 2019, UHG had an overall decrease of 714 P01 cases (21.5%) and a decrease of 152 P03 cases (14.4%). In this time, LUH had an increase of 9 P01 cases (0.8%) but a decrease of 48 P03 cases (58.5%). CONCLUSIONS: There has been a significant impact on the provision of both diagnostic and therapeutic services in North-West of Ireland due to the COVID-19 pandemic.

Skin cancer margin detection using nanosensitive optical coherence tomography and a comparative study with confocal microscopy.

Excision biopsy and histology represent the gold standard for morphological investigation of the skin, in particular for cancer diagnostics. Nevertheless, a biopsy may alter the original morphology, usually requires several weeks for results, is non-repeatable on the same site and always requires an iatrogenic trauma. Hence, diagnosis and clinical management of diseases may be substantially improved by new non-invasive imaging techniques. Optical Coherence Tomography (OCT) is a non-invasive depth-resolved optical imaging modality based on low coherence interferometry that enables high-resolution, cross-sectional imaging in biological tissues and it can be used to obtain both structural and functional information. Beyond the resolution limit, it is not possible to detect structural and functional information using conventional OCT. In this paper, we present a recently developed technique, nanosensitive OCT (nsOCT), improved using broadband supercontinuum laser, and demonstrate nanoscale sensitivity to structural changes within ex vivo human skin tissue. The extended spectral bandwidth permitted access to a wider distribution of spatial frequencies and improved the dynamic range of the nsOCT. Firstly, we demonstrate numerical and experimental detection of a few nanometers structural difference using the nsOCT method from single B-scan images of phantoms with sub-micron periodic structures, acting like Bragg gratings, along the depth. Secondly, our study shows that nsOCT can distinguish nanoscale structural changes at the skin cancer margin from the healthy region in en face images at clinically relevant depths. Finally, we compare the nsOCT en face image with a high-resolution confocal microscopy image to confirm the structural differences between the healthy and lesional/cancerous regions, allowing the detection of the skin cancer margin.

Epithelial displacement during breast needle core biopsy causes diagnostic difficulties in subsequent surgical excision specimens.

BACKGROUND: The use of needle core biopsy (NCB) as part of triple assessment for non-operative evaluation and diagnosis of breast lesions is now routine practice. Trauma to breast tissue during NCB may result in displacement of breast epithelium and may lead to diagnostic difficulty in subsequent excision specimens. METHODS: The cases of seven mammographically detected breast lesions in which epithelial displacement due to NCB was identified and caused problems in confirmation of tumour size, assessment of surgical margins, and interpretation of possible invasive carcinoma and lymphovascular invasion are reported here. CONCLUSION: Previous observations that epithelial displacement is more likely to occur when the interval between NCB and surgical excision is short are supported.

Spindle assembly checkpoint protein expression correlates with cellular proliferation and shorter time to recurrence in ovarian cancer.

Ovarian carcinoma (OC) is the most lethal of the gynecological malignancies, often presenting at an advanced stage. Treatment is hampered by high levels of drug resistance. The taxanes are microtubule stabilizing agents, used as first-line agents in the treatment of OC that exert their apoptotic effects through the spindle assembly checkpoint. BUB1-related protein kinase (BUBR1) and mitotic arrest deficient 2 (MAD2), essential spindle assembly checkpoint components, play a key role in response to taxanes. BUBR1, MAD2, and Ki-67 were assessed on an OC tissue microarray platform representing 72 OC tumors of varying histologic subtypes. Sixty-one of these patients received paclitaxel and platinum agents combined; 11 received platinum alone. Overall survival was available for all 72 patients, whereas recurrence-free survival (RFS) was available for 66 patients. Increased BUBR1 expression was seen in serous carcinomas, compared with other histologies (P = .03). Increased BUBR1 was significantly associated with tumors of advanced stage (P = .05). Increased MAD2 and BUBR1 expression also correlated with increased cellular proliferation (P < .0002 and P = .02, respectively). Reduced MAD2 nuclear intensity was associated with a shorter RFS (P = .03), in ovarian tumors of differing histologic subtype (n = 66). In this subgroup, for those women who received paclitaxel and platinum agents combined (n = 57), reduced MAD2 intensity also identified women with a shorter RFS (P < .007). For the entire cohort of patients, irrespective of histologic subtype or treatment, MAD2 nuclear intensity retained independent significance in a multivariate model, with tumors showing reduced nuclear MAD2 intensity identifying patients with a poorer RFS (P = .05).

Idiopathic lymphocytic pleuritis: radiographic and high-resolution CT appearances and changes in response to therapy in two adults.

Inflammatory conditions of the pleura characterized by a predominantly lymphocytic infiltrate are described in several disorders. The commonest underlying aetiologies include tuberculous infection, autoimmune disorders (particularly Sjogren's syndrome), and post coronary artery bypass graft surgery. Idiopathic lymphocytic pleuritis (ILP) is a rare form of diffuse pleural inflammation characterized by extensive lymphocytic infiltration for which no cause is found. Radiological descriptions of ILP are limited. We describe the radiographic and high-resolution computed tomography (HRCT) imaging features and response to corticosteroid therapy of ILP in two adults. Both patients presented with bilateral diffuse pleural thickening of >10 mm thickness extending >10 cm craniocaudally with small focal areas of atelectasis. Both cases demonstrated marked improvement in the degree and extent of pleural thickening and rounded atelectasis following corticosteroid therapy. HRCT provided a useful noninvasive method of assessing disease response to therapy.

MAD2 downregulation in hypoxia is independent of promoter hypermethylation.

Aberrant expression of the MAD2 protein has been linked to chromosomal instability, malignant transformation and chemoresistance. Although reduced MAD2 expression is well recognised in human cancer cell lines, the mechanism(s) underlying its downregulation remain elusive. The objective of this study was to establish the impact of hypoxia on MAD2 expression and to investigate the potential role of aberrant promoter methylation as a possible mechanism of MAD2 downregulation. For this purpose, three ovarian cancer cell lines, displaying differing levels of MAD2, were treated with chromatin modifying drugs, pre and post-hypoxia exposure and a DHPLC analysis of DNA promoter methylation carried out. We show that hypoxia induces downregulation of MAD2 expression, independently of MAD2 promoter methylation. We also show no evidence of MAD2 promoter methylation in breast and prostate cancer cells or in breast cancer clinical material. While our findings provide no evidence for MAD2 promoter methylation, we show a concomitant upregulation of p21 with downregulation of MAD2 in hypoxia. Our in vitro results were also confirmed in an ovarian cancer tissue microarray (TMA), where a reciprocal staining of MAD2 and CAIX was found in 21/60 (35%) of tumours. In summary, MAD2 downregulation may be a crucial mechanism by which hypoxic cells become chemorefractory. This stems from our previous work where we demonstrated that MAD2 downregulation induces cellular senescence, a viable cellular fate, with resultant cellular resistance to paclitaxel. Moreover, MAD2 downregulation could play a central role in the induction of chemoresistance in hypoxia, a key tumour microenvironment associated with chemoresistance.