| 1. |
- Brandão, Andreia, et al.
(author)
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The CHEK2 Variant C.349A>G Is Associated with Prostate Cancer Risk and Carriers Share a Common Ancestor
- 2020
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In: Cancers. - : MDPI AG. - 2072-6694. ; 12:11
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Journal article (peer-reviewed)abstract
- The identification of recurrent founder variants in cancer predisposing genes may have important implications for implementing cost-effective targeted genetic screening strategies. In this study, we evaluated the prevalence and relative risk of the CHEK2 recurrent variant c.349A>G in a series of 462 Portuguese patients with early-onset and/or familial/hereditary prostate cancer (PrCa), as well as in the large multicentre PRACTICAL case-control study comprising 55,162 prostate cancer cases and 36,147 controls. Additionally, we investigated the potential shared ancestry of the carriers by performing identity-by-descent, haplotype and age estimation analyses using high-density SNP data from 70 variant carriers belonging to 11 different populations included in the PRACTICAL consortium. The CHEK2 missense variant c.349A>G was found significantly associated with an increased risk for PrCa (OR 1.9; 95% CI: 1.1-3.2). A shared haplotype flanking the variant in all carriers was identified, strongly suggesting a common founder of European origin. Additionally, using two independent statistical algorithms, implemented by DMLE+2.3 and ESTIAGE, we were able to estimate the age of the variant between 2300 and 3125 years. By extending the haplotype analysis to 14 additional carrier families, a shared core haplotype was revealed among all carriers matching the conserved region previously identified in the high-density SNP analysis. These findings are consistent with CHEK2 c.349A>G being a founder variant associated with increased PrCa risk, suggesting its potential usefulness for cost-effective targeted genetic screening in PrCa families.
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| 2. |
- Crippa, Alessio, et al.
(author)
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The ProBio trial : molecular biomarkers for advancing personalized treatment decision in patients with metastatic castration-resistant prostate cancer
- 2020
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In: Trials. - : BioMed Central. - 1745-6215. ; 21:1
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Journal article (peer-reviewed)abstract
- Background: Multiple therapies exist for patients with metastatic castration-resistant prostate cancer (mCRPC). However, their improvement on progression-free survival (PFS) remains modest, potentially explained by tumor molecular heterogeneity. Several prognostic molecular biomarkers have been identified for mCRPC that may have predictive potential to guide treatment selection and prolong PFS. We designed a platform trial to test this hypothesis.Methods: The Prostate-Biomarker (ProBio) study is a multi-center, outcome-adaptive, multi-arm, biomarker-driven platform trial for tailoring treatment decisions for men with mCRPC. Treatment decisions in the experimental arms are based on biomarker signatures defined as mutations in certain genes/pathways suggested in the scientific literature to be important for treatment response in mCRPC. The biomarker signatures are determined by targeted sequencing of circulating tumor and germline DNA using a panel specifically designed for mCRPC.Discussion: Patients are stratified based on the sequencing results and randomized to either current clinical practice (control), where the treating physician decides treatment, or to molecularly driven treatment selection based on the biomarker profile. Outcome-adaptive randomization is implemented to early identify promising treatments for a biomarker signature. Biomarker signature-treatment combinations graduate from the platform when they demonstrate 85% probability of improving PFS compared to the control arm. Graduated combinations are further evaluated in a seamless confirmatory trial with fixed randomization. The platform design allows for new drugs and biomarkers to be introduced in the study.Conclusions: The ProBio design allows promising treatment-biomarker combinations to quickly graduate from the platform and be confirmed for rapid implementation in clinical care.
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| 3. |
- Harbs, Justin, 1994-
(author)
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Circulating markers of risk and etiology in colorectal cancer
- 2023
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Doctoral thesis (other academic/artistic)abstract
- Background: Colorectal cancer is the third most commonly diagnosed cancer in men and women. Worldwide around 2 million individuals are diagnosed each year – a number expected to increase as colorectal cancer risk factors become more prevalent. In men and women there is a difference in incidence, which possibly could be explained by inherent differences, including sex hormone profiles. The prognosis of colorectal cancer is highly dependent on the stage at diagnosis, with individuals diagnosed at early stages having the best long-term survival. However, as onset of symptoms can be diffuse, many individuals are diagnosed at later stages when survival rates are significantly poorer. Therefore, screening and prevention strategies to detect colorectal cancer at earlier stages or remove cancer precursors such as polyps may be key to increasing survival. Commonly used screening tools today include fecal blood tests and colonoscopy, but they have modest accuracy or may not be cost-effective. Being able to identify markers in blood, either for early detection, as a complementary or alternative screening method, or for risk stratification, could aid in solving this problem. Aim: The overall of aim of the thesis was to improve our understanding of underlying factors contributing to CRC etiology and to find biomarkers associated with CRC that could aid in the future development of effective risk prediction models. Methods: All studies included in this thesis were based on a case-control cohort nested within the Northern Sweden Health and Disease Study (NSHDS). Additionally in paper I, we also used data from the European Prospective Investigation into Cancer and Nutrition (EPIC), a large multi-center cohort study. In this paper we examined associations between sex hormones, sex hormone binding globulin (SHBG), and colon cancer in men. The study included 690 colon cancer cases and 690 matched controls. Paper II was a longitudinal study, using repeated samples from 80 men, on circulating sex hormones, SHBG, and DNA methylation in white blood cells. Papers III and IV were nested case-control studies on proteins and colorectal cancer risk with Paper III divided into a discovery and a validation phase. In the first phase, which included 69 colorectal cancer case-control pairs with repeated samples, 160 unique proteins related to inflammation and oncology were analyzed. In the second phase, 13 proteins that were significantly associated with colorectal cancer risk, together with 8 proteins identified from the literature, were measured on a custom panel, and validated in a larger material consisting of 1000 case-control pairs. In paper IV, which included 195 colorectal cancer case-control pairs, the protein analysis was extended to include 1536 proteins linked to oncology, inflammation, neurology, and metabolism. In papers using a matched case-control design, conditional i logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CI) for the associations. For longitudinal analyses, mixed effects models were used to estimate associations. Results: In paper I, we observed a statistically significant inverse association between circulating levels of testosterone and colon cancer. For SHBG there was a statistically significant inverse association prior to adjustment of testosterone and estradiol levels. In paper II, we found one novel genome-wide significant association between circulating levels of dehydroepiandrosterone and DNA methylation at the cg14319657 CpG site. In addition, we also identified more than 40 differentially methylated regions associated with levels of sex hormones and SHBG. In paper III, we first identified 13 proteins associated with CRC risk in the discovery phase. In the validation phase, however, none of the proteins remained significantly associated with colorectal cancer. When stratifying by tumor site, FGF-21 and PPY, were statically significant in colon and rectal cancer respectively, and showed some modest increase in predictive performance. In paper IV, we identified 20 proteins surpassing a significance threshold of 0.005. One protein, TFF3 (Trefoil Factor 3), which was positively associated with colorectal, also withstood strict Bonferroni correction. In addition, we validated several proteins, including AREG, CEA, and LGALS4, which were identified as biomarker candidates in previous studies. Conclusions: Our results support the hypothesis that circulating sex hormones play a role in male colon cancer etiology and that this may partly explain the difference in colorectal cancer incidence between men and women. Furthermore, our findings suggest a possible link between circulating sex hormones, SHBG and DNA methylation, which could be of interest in the etiology of colorectal cancer as well as other hormone-dependent diseases. Finally, we also identified several proteins associated with colorectal cancer, some of which have shown potential as screening markers.
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| 4. |
- Slanina, Tomáš, et al.
(author)
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Impact of Excited-State Antiaromaticity Relief in a Fundamental Benzene Photoreaction Leading to Substituted Bicyclo[3.1.0]hexenes
- 2020
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In: Journal of the American Chemical Society. - : American Chemical Society. - 0002-7863 .- 1520-5126. ; 142:25, s. 10942-10954
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Journal article (peer-reviewed)abstract
- Benzene exhibits a rich photochemistry which can provide access to complex molecular scaffolds that are difficult to access with reactions in the electronic ground state. While benzene is aromatic in its ground state, it is antiaromatic in its lowest ππ∗ excited states. Herein, we clarify to what extent relief of excited-state antiaromaticity (ESAA) triggers a fundamental benzene photoreaction: the photoinitiated nucleophilic addition of solvent to benzene in acidic media leading to substituted bicyclo[3.1.0]hex-2-enes. The reaction scope was probed experimentally, and it was found that silyl-substituted benzenes provide the most rapid access to bicyclo[3.1.0]hexene derivatives, formed as single isomers with three stereogenic centers in yields up to 75% in one step. Two major mechanism hypotheses, both involving ESAA relief, were explored through quantum chemical calculations and experiments. The first mechanism involves protonation of excited-state benzene and subsequent rearrangement to bicyclo[3.1.0]hexenium cation, trapped by a nucleophile, while the second involves photorearrangement of benzene to benzvalene followed by protonation and nucleophilic addition. Our studies reveal that the second mechanism is operative. We also clarify that similar ESAA relief leads to puckering of S1-state silabenzene and pyridinium ion, where the photorearrangement of the latter is of established synthetic utility. Finally, we identified causes for the limitations of the reaction, information that should be valuable in explorations of similar photoreactions. Taken together, we reveal how the ESAA in benzene and 6π-electron heterocycles trigger photochemical distortions that provide access to complex three-dimensional molecular scaffolds from simple reactants.
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| 5. |
- Vilhjalmsson, Dadi, et al.
(author)
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Transanal formation of anastomosis using C-REX device is feasible and effective in high anterior resection
- 2023
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In: International Journal of Colorectal Disease. - 0179-1958. ; 38:1
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Journal article (peer-reviewed)abstract
- Purpose: C-REX is a novel instrument for creating stapleless colorectal anastomosis by compression. The aim of this study was to evaluate the feasibility and effectiveness of C-REX in open and laparoscopic high anterior resections. Methods: A prospective clinical safety study on 21 patients reconstructed with C-REX colorectal anastomosis following high anterior resection of the sigmoid colon using two different devices for intraabdominal (n = 6) or transanal (n = 15) placement of the anastomotic rings. Any signs of complications were prospectively monitored by a predefined protocol. Anastomotic contact pressure (ACP) was measured via a catheter-based system, and time for evacuation of the anastomotic rings by the natural route was noted. Blood samples were collected daily, and flexible endoscopy was performed postoperatively to examine macroscopic appearance of the anastomoses. Results: One of six patients operated with the intraabdominal anastomosis technique with an ACP of 50 mBar had to be reoperated because of anastomotic leakage. None of the 15 patients operated with the transanal technique (5 open and 10 laparoscopic procedures) had anastomotic complications, and their ACP ranged between 145 and 300 mBar. C-REX rings were uneventfully expelled by the natural route in all patients after a median of 10 days. Flexible endoscopy showed well-healed anastomoses without stenosis in 17 patients and a moderate subclinical stricture in one patient. Conclusion: These results indicate that the novel transanal C-REX device is a feasible and effective method for colorectal anastomosis following high anterior resections, irrespective of open or laparoscopic approach. Moreover, C-REX allows measurement of intraoperative ACP and thereby a quantitative evaluation of the anastomotic integrity.
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| 6. |
- Waldén, Mauritz, et al.
(author)
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A Head-to-head Comparison of Prostate Cancer Diagnostic Strategies Using the Stockholm3 Test, Magnetic Resonance Imaging, and Swedish National Guidelines : Results from a Prospective Population-based Screening Study
- 2022
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In: European Urology Open Science. - : Elsevier. - 2666-1691 .- 2666-1683. ; 38, s. 32-39
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Journal article (peer-reviewed)abstract
- Background: Strategies for early detection of prostate cancer aim to detect clinically significant prostate cancer (csPCa) and avoid detection of insignificant cancers and unnecessary biopsies. Swedish national guidelines (SNGs), years 2019 and 2020, involve prostate-specific antigen (PSA) testing, clinical variables, and magnetic resonance imaging (MRI). The Stockholm3 test and MRI have been suggested to improve selection of men for prostate biopsy. Performance of SNGs compared with the Stockholm3 test or MRI in a screening setting is unclear.Objective: To compare strategies based on previous and current national guidelines, Stockholm3, and MRI to select patients for biopsy in a screening-by-invitation setting.Design setting and participants: All participants underwent PSA test, and men with PSA ≥3 ng/ml underwent Stockholm3 testing and MRI. Men with Stockholm3 ≥11%, Prostate Imaging Reporting and Data System score ≥3 on MRI, or indication according to SNG-2019 or SNG-2020 were referred to biopsy.Outcome measurements and statistical analysis: The primary outcome was the detection of csPCa at prostate biopsy, defined as an International Society of Urological Pathology (ISUP) grade of ≥2.Results and limitations: We invited 8764 men from the general population, 272 of whom had PSA ≥3 ng/ml. The median PSA was 4.1 (interquartile range: 3.4-5.8), and 136 of 270 (50%) who underwent MRI lacked any pathological lesions. In total, 37 csPCa cases were diagnosed. Using SNG-2019, 36 csPCa cases with a high biopsy rate (179 of 272) were detected and 49 were diagnosed with ISUP 1 cancers. The Stockholm3 strategy diagnosed 32 csPCa cases, with 89 biopsied and 27 ISUP 1 cancers. SNG-2020 detected 32 csPCa and 33 ISUP 1 cancer patients, with 99 men biopsied, and the MRI strategy detected 30 csPCa and 35 ISUP 1 cancer cases by biopsying 123 men. The latter two strategies generated more MRI scans than the Stockholm3 strategy (n = 270 vs 33).Conclusions: Previous guidelines provide high detection of significant cancer but at high biopsy rates and detection of insignificant cancer. The Stockholm3 test may improve diagnostic precision compared with the current guidelines or using only MRI.Patient summary: The Stockholm3 test facilitates detection of significant cancer, and reduces the number of biopsies and detection of insignificant cancer.
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| 7. |
- Watts, Eleanor L., et al.
(author)
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Observational and genetic associations between cardiorespiratory fitness and cancer : a UK Biobank and international consortia study
- 2024
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In: British Journal of Cancer. - : Springer Nature. - 0007-0920 .- 1532-1827. ; 130, s. 114-124
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Journal article (peer-reviewed)abstract
- Background: The association of fitness with cancer risk is not clear.Methods: We used Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for risk of lung, colorectal, endometrial, breast, and prostate cancer in a subset of UK Biobank participants who completed a submaximal fitness test in 2009-12 (N = 72,572). We also investigated relationships using two-sample Mendelian randomisation (MR), odds ratios (ORs) were estimated using the inverse-variance weighted method.Results: After a median of 11 years of follow-up, 4290 cancers of interest were diagnosed. A 3.5 ml O2⋅min−1⋅kg−1 total-body mass increase in fitness (equivalent to 1 metabolic equivalent of task (MET), approximately 0.5 standard deviation (SD)) was associated with lower risks of endometrial (HR = 0.81, 95% CI: 0.73–0.89), colorectal (0.94, 0.90–0.99), and breast cancer (0.96, 0.92–0.99). In MR analyses, a 0.5 SD increase in genetically predicted O2⋅min−1⋅kg−1 fat-free mass was associated with a lower risk of breast cancer (OR = 0.92, 95% CI: 0.86–0.98). After adjusting for adiposity, both the observational and genetic associations were attenuated.Discussion: Higher fitness levels may reduce risks of endometrial, colorectal, and breast cancer, though relationships with adiposity are complex and may mediate these relationships. Increasing fitness, including via changes in body composition, may be an effective strategy for cancer prevention.
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