42 research outputs found
Association of adult attachment with delays in accessing specialist care in women with ovarian cancer
OBJECTIVE: Advanced stage at diagnosis and delayed presentation are common in ovarian cancer (OC). The objective of the current study was to explore the association of adult attachment pattern with delays in accessing specialist oncology care in patients with OC. METHODS: A cross-sectional structured interview study of patients with OC presenting to an Indian cancer center was undertaken. Consenting patients completed Experiences of Close Relationships-Relationship Style questionnaire (ECR-RS) and Medical Outcome Survey-Social Support Survey (MOS-SSS). Multivariate linear regression with "time to presentation to cancer specialist" as the dependent variable was undertaken. RESULTS: In all, 132 of 155 (85%) patients with OC who were invited were interviewed. An increased ECR-RS attachment anxiety score (P = .01) and being part of a multigenerational extended household (P = .04) were both independently associated with delay in presentation to a cancer specialist. There was no association between delay in presentation and social support. CONCLUSIONS: Among patients with OC, adult attachment may contribute to delays in presentation. It may be important for the cancer symptom awareness efforts in primary care to include educating physicians on recognizing and interacting with patients with insecure attachment styles. The association of delays in presentation for women with OC living in multigenerational extended households needs more indepth exploration. Supplemental data for this article is available online at https://doi.org/10.1080/07347332.2022.2025510
Determining the Potential of DNA Damage Response (DDR) Inhibitors in Cervical Cancer Therapy
Cisplatin-based chemo-radiotherapy (CRT) is the standard treatment for advanced cervical cancer (CC) but the response rate is poor (46–72%) and cisplatin is nephrotoxic. Therefore, better treatment of CC is urgently needed. We have directly compared, for the first time, the cytotoxicity of four DDR inhibitors (rucaparib/PARPi, VE-821/ATRi, PF-477736/CHK1i and MK-1775/WEE1i) as single agents, and in combination with cisplatin and radiotherapy (RT) in a panel of CC cells. All inhibitors alone caused concentration-dependent cytotoxicity. Low ATM and DNA-PKcs levels were associated with greater VE-821 cytotoxicity. Cisplatin induced ATR, CHK1 and WEE1 activity in all of the cell lines. Cisplatin only activated PARP in S-phase cells, but RT activated PARP in the entire population. Rucaparib was the most potent radiosensitiser and VE-821 was the most potent chemosensitiser. VE-821, PF-47736 and MK-1775 attenuated cisplatin-induced S-phase arrest but tended to increase G2 phase accumulation. In mice, cisplatin-induced acute kidney injury was associated with oxidative stress and PARP activation and was prevented by rucaparib. Therefore, while all inhibitors investigated may increase the efficacy of CRT, the greatest clinical potential of rucaparib may be in limiting kidney damage, which is dose-limiting
Pathological chemotherapy response score is prognostic in tubo-ovarian high-grade serous carcinoma: A systematic review and meta-analysis of individual patient data
There is a need to develop and validate biomarkers for treatment response and survival in tubo-ovarian high-grade serous carcinoma (HGSC). The chemotherapy response score (CRS) stratifies patients into complete/near-complete (CRS3), partial (CRS2), and no/minimal (CRS1) response after neoadjuvant chemotherapy (NACT). Our aim was to review current evidence to determine whether the CRS is prognostic in women with tubo-ovarian HGSC treated with NACT.This article is freely available via Open Access. Click on the Publisher URL to access the full-text via the publisher's site
Development of a functional assay to test for homologous recombination in ovarian cancer
Background: PARP inhibitors selectively target homologous recombination (HR) defective cells and show good clinical activity in hereditary breast and ovarian cancer associated with BRCAl12 mutations. A high proportion (up to 50%) of sporadic epithelial ovarian cancers (EOC) could be deficient in HR due to genetic or epigenetic inactivation of BR CA 112 or other HR genes. Therefore there is a potential for extending the use of P ARP inhibitors to these patients if HR status can be identified. Aims: To develop a functional assay of HR status that correlates with sensitivity to the PARP inhibitor AG014699. Methods: Primary cultures were derived from ascitic fluid from patients with EOCs. HR status was investigated by yH2AX and RAD51 focus formation by immunofluorescence. Cytotoxicity to the PARP inhibitor AG014699 was tested by SRB and cell survival assay. Clinical outcome and platinum sensitivity was correlated prospectively with predicted HR status. Results: The success rate of generating primary cultures (n=75) was> 90%. 48 EOCs were evaluated for HR status and cytotoxicity; HR deficiency (HRD) was predicted in 25/48(52%) cultures showing no increase in RAD51 foci. Cytotoxicity was observed in 23/25 HR deficient (PPV-93%) but none of 23 HR competent (NPV-I00%) cultures. 35 patients completed clinical follow up; compared to HR competent patients (n=18), the HR deficient group (n=17) were predominantly serous (p=0.041), sensitive to platinum (58.8% vs. 29.4%) with lower tumour progression rates at 6 months (5.9% vs. 27.8%) and lower death rates at 12 months (17.6% vs. 44.4%). Conclusion: HR status can be determined in primary cancer samples by RAD51 focus formation. 50% EOCs appear to have HR defects. HRD as predicted by the RAD51 assay correlates with ex vivo PARP inhibitor sensitivity, clinical platinum sensitivity and improved survival outcome.EThOS - Electronic Theses Online ServiceGBUnited Kingdo
In-silico analysis of TCGA data showing multiple POLE-like favourable subgroups overlapping with TP53 mutated endometrial cancer: Implications for clinical practice in low and middle-income countries
Introduction: The Cancer Genome Atlas cohort of endometrial carcinoma (TCGA-UCEC) includes almost 40% TP53-mutants encompassing missense and truncated variants. TCGA revealed ‘POLE’, characterized by POLE gene bearing exonuclease domain mutation (EDM), as the prognostically best molecular profile. The worst profile was characterized by TP53-mutated Type 2 cancer requiring adjuvant therapy having cost implications in low-resource settings. We aimed to find more ‘POLE-like’ favourable subgroups by searching TCGA cohort, especially within TP53 mutated risk group, that could eventually avoid adjuvant treatment in resource-poor settings. Method: Our study was an in-silico survival analysis performed on the TCGA-UCEC dataset using SPSS statistical package. TP53 and POLE mutations, microsatellite instability (MSI), time-to-event and clinicopathological parameters were compared among 512 endometrial cancer cases. Deleterious POLE-mutations were identified by Polyphen2. Progression free survival was studied using Kaplan-Meier plots keeping original ‘POLE’ as comparator. Result: In presence of wild type (WT)-TP53, other deleterious POLE-mutations behaved like POLE-EDM. Only truncated and not missense TP53 benefitted from POLE/MSI overlap. However, TP53 missense mutation, Y220C, was found to be as favourable as ‘POLE’. Overlapping POLE, MSI and WT-TP53 also performed favourably. Truncated TP53 overlapped with POLE and/or MSI, TP53 Y220C alone and, WT-TP53 overlapped with POLE and MSI both, were named ‘POLE-like’ for prognostically behaving like the comparator ‘POLE’. Conclusion: Obesity being a lesser frequent event in low and middle-income countries (LMICs), relative proportion of women with lower BMI and Type 2 endometrial cancers may be high. Identification of ‘POLE-like’ groups may facilitate therapeutic de-escalation in some TP53-mutated cases - a novel option. Instead of 5% (POLE-EDM), potential beneficiary would then comprise 10% (POLE-like) of TCGA-UCEC
Differences in Durability of PARP Inhibition by Clinically Approved PARP Inhibitors: Implications for Combinations and Scheduling
Six PARP inhibitors (PARPi) are approved for cancer therapy as monotherapy agents in daily or twice-daily continuous dosing schedules to maintain the necessary continuous suppression of PARP activity. Continuous PARP inhibition is required for single-agent anticancer activity. To investigate if such intense schedules are necessary, we determined the durability of PARP inhibition up to 72 h after a 1 h pulse of 1 µM of five of the approved PARPi, rucaparib, olaparib, niraparib, talazoparib and pamiparib, in IGROV-1 and ES-2 (human ovarian cancer) cells. Rucaparib caused the most persistent inhibition of PARP activity when maintained at ≥75% at 72 h after drug withdrawal in both IGROV-1 and ES-2 cells, but inhibition was more rapidly lost with the other PARPi. PARPi are also under clinical investigation with ATR inhibitors, and thus, we evaluated the implications for scheduling with an ATR inhibitor (VE-821). Rucaparib enhanced VE-821 cytotoxicity in co-exposure, sequential and delayed (24 h drug-free) schedules in IGROV-1 and ES-2 cells. Olaparib and niraparib enhanced VE-821 cytotoxicity only in co-exposed cells and not in sequential exposures. These data have clinical implications for the scheduling of PARPi as a monotherapy and in combination with ATR inhibitors and other cytotoxic drugs.Medicine, Faculty ofNon UBCReviewedFacultyResearche
Tissue multifractality and hidden Markov model based integrated framework for optimum precancer detection
We report the application of a hidden Markov model (HMM) on multifractal tissue optical properties derived via the Born approximation-based inverse light scattering method for effective discrimination of precancerous human cervical tissue sites from the normal ones. Two global fractal parameters, generalized Hurst exponent and the corresponding singularity spectrum width, computed by multifractal detrended fluctuation analysis (MFDFA), are used here as potential biomarkers. We develop a methodology that makes use of these multifractal parameters by integrating with different statistical classifiers like the HMM and support vector machine (SVM). It is shown that the MFDFA-HMM integrated model achieves significantly better discrimination between normal and different grades of cancer as compared to the MFDFA-SVM integrated model.Published versio
11-Methoxytetrahydroalstonine, a heteroyohimbinoid alkaloid from Vinca major
The alkaloid 11-methoxytetrahydroalstonine has been isolated for the first time from a natural source, viz. Vinca major. Its structure and stereochemistry have been established by extensive <SUP>1</SUP>H and <SUP>13</SUP>C NMR spectral analyses including COSY experiments. The assigned structure was confirmed by X-ray crystallography