Significance The major portion of hereditary breast cancer still remains unexplained, and many susceptibility loci are yet to be found. Exome sequencing of 24 high-risk familial BRCA1/2 -negative ...breast cancer patients and further genotyping of a large sample set of breast/ovarian cancer cases and controls was used to discover previously unidentified susceptibility alleles and genes. A significant association of a FANCM nonsense mutation with breast cancer, especially triple-negative breast cancer, identifies FANCM as a breast cancer susceptibility gene. Identification of such risk alleles is expected to improve cancer risk assessment for breast cancer patients and families, and may lead to improvements in the prevention, early diagnosis, and treatment of cancer.
Inherited predisposition to breast cancer is known to be caused by loss-of-function mutations in BRCA1 , BRCA2 , PALB2 , CHEK2 , and other genes involved in DNA repair. However, most families severely affected by breast cancer do not harbor mutations in any of these genes. In Finland, founder mutations have been observed in each of these genes, suggesting that the Finnish population may be an excellent resource for the identification of other such genes. To this end, we carried out exome sequencing of constitutional genomic DNA from 24 breast cancer patients from 11 Finnish breast cancer families. From all rare damaging variants, 22 variants in 21 DNA repair genes were genotyped in 3,166 breast cancer patients, 569 ovarian cancer patients, and 2,090 controls, all from the Helsinki or Tampere regions of Finland. In Fanconi anemia complementation gene M ( FANCM ), nonsense mutation c.5101C>T (p.Q1701X) was significantly more frequent among breast cancer patients than among controls odds ratio (OR) = 1.86, 95% CI = 1.26–2.75; P = 0.0018, with particular enrichment among patients with triple-negative breast cancer (TNBC; OR = 3.56, 95% CI = 1.81–6.98, P = 0.0002). In the Helsinki and Tampere regions, respectively, carrier frequencies of FANCM p.Q1701X were 2.9% and 4.0% of breast cancer patients, 5.6% and 6.6% of TNBC patients, 2.2% of ovarian cancer patients (from Helsinki), and 1.4% and 2.5% of controls. These findings identify FANCM as a breast cancer susceptibility gene, mutations in which confer a particularly strong predisposition for TNBC.
Mutations in BRCA1 and BRCA2 genes predispose to breast and ovarian cancer (BC/OC) with a high lifetime risk, whereas mutations in PALB2, CHEK2, ATM, FANCM, RAD51C and RAD51D genes cause a moderately ...elevated risk. In the Finnish population, recurrent mutations have been identified in all of these genes, the latest being CHEK2 c.319+2T>A and c.444+1G>A. By genotyping 3,156 cases and 2,089 controls, we estimated the frequencies of CHEK2 c.319+2T>A and c.444+1G>A in Finnish BC patients. CHEK2 c.319+2T>A was detected in 0.7% of the patients, and it was associated with a high risk of BC in the unselected patient group (OR = 5.40 95% CI 1.58–18.45, p = 0.007) and similarly in the familial patient group. CHEK2 c.444+1G>A was identified in 0.1% of all patients. Additionally, we evaluated the combined prevalence of recurrent moderate‐risk gene mutations in 2,487 BC patients, 556 OC patients and 261 BRCA1/2 carriers from 109 families. The overall frequency of the mutations was 13.3% in 1,141 BRCA1/2‐negative familial BC patients, 7.5% in 1,727 unselected BC patients and 7.2% in 556 unselected OC patients. At least one moderate‐risk gene mutation was found in 12.5% of BRCA1 families and 7.1% of BRCA1 index patients, as well as in 17.0% of BRCA2 families and 11.3% of BRCA2 index patients, and the mutations were associated with an additional risk in the BRCA1/2 index patients (OR = 2.63 1.15–5.48, p = 0.011). These results support gene panel testing of even multiple members of BC families where several mutations may segregate in different individuals.
What's new?
In the Finnish population, a small number of recurrent mutations account for the majority of deleterious variations in breast and ovarian cancer susceptibility genes. The authors investigated 12 recurrent moderate‐risk mutations in Finnish breast and ovarian cancer patients. These mutations were found with similar frequency in unselected patients and BRCA1/2‐positive familial index patients, twice as often as in population controls. In addition, a novel association was identified between breast cancer risk and CHEK2 variant c.319+2T>A. The findings highlight the relevance of gene panel testing for breast and ovarian cancer risk assessment and its potential use for assessing breast cancer families with members who may carry different mutations.
Our aim was to investigate in a real-life prospective patient cohort how CYP2C19 loss-of-function (LOF) variants and CYP2C19 inhibitor omeprazole or esomeprazole influence the incidence of ...cardiovascular events in patients using clopidogrel. Data based simultaneously on these factors are conflicting and sparse. A cohort of prospective patients (n=1972) with acute coronary syndrome (ACS) (n=1302) or symptomatic chronic coronary disease (n=656) was followed for 365 days after hospitalization with information on purchased prescription drugs, hospital discharge, death and genotype for CYP2C19*2, CYP2C19*3, and CYP2C19*8 LOF variants. The primary study outcome measurement was cardiovascular death or recurring myocardial infarction or stroke. Altogether, 608 patients (30.8%) carried CYP2C19 LOF alleles. During the 365-day follow-up 252 patients (12.8%) had an ischemic vascular event. Cardiovascular events were significantly more frequent in carriers of CYP2C19 LOF alleles 14.8% (95% CI, 11.7-17.8) than in non-carriers 10.8% (95% CI, 9.0-12.6) (P = .0159). Omeprazole or esomeprazole use was similar among LOF allele carriers (n=131, 21.5%) and non-carriers (n=250, 18.3%) (P = .185). Cardiovascular events were significantly more common in a composite group consisting of all CYP2C19 LOF carriers regardless of PPI use status and non-carriers using omeprazole or esomeprazole than in non-carriers not using omeprazole or esomeprazole: 14.8% (95% CI, 12.2-17.3) vs. 9.9% (95% CI, 8.0-11.9) (P = .00173). We observed significantly more cardiovascular events in carriers of CYP2C19 LOF variants and in non-carriers using omeprazole or esomeprazole. For optimal patient care, both genetics and concomitant medication should be considered.
Ticagrelor and rosuvastatin are often used concomitantly after atherothrombotic events. Several cases of rhabdomyolysis during concomitant ticagrelor and rosuvastatin have been reported, suggesting a ...drug–drug interaction. We showed recently that ticagrelor inhibits breast cancer resistance protein (BCRP) and organic anion transporting polypeptide (OATP) 1B1, 1B3, and 2B1‐mediated rosuvastatin transport in vitro. The aim of this study was to investigate the effects of ticagrelor on rosuvastatin pharmacokinetics in humans. In a randomized, crossover study, 9 healthy volunteers ingested a single dose of 90 mg ticagrelor or placebo, followed by a single 10 mg dose of rosuvastatin 1 hour later. Ticagrelor 90 mg or placebo were additionally administered 12, 24, and 36 hours after their first dose. Ticagrelor increased rosuvastatin area under the plasma concentration‐time curve (AUC) and peak plasma concentration 2.6‐fold (90% confidence intervals: 1.8–3.8 and 1.7–4.0, P = 0.001 and P = 0.003), and prolonged its half‐life from 3.1 to 6.6 hours (P = 0.009). Ticagrelor also decreased the renal clearance of rosuvastatin by 11% (3%–19%, P = 0.032). The N‐desmethylrosuvastatin:rosuvastatin AUC0–10h ratio remained unaffected by ticagrelor. Ticagrelor had no effect on the plasma concentrations of the endogenous OATP1B substrates glycodeoxycholate 3‐O‐glucuronide, glycochenodeoxycholate 3‐O‐glucuronide, glycodeoxycholate 3‐O‐sulfate, and glycochenodeoxycholate 3‐O‐sulfate, or the sodium‐taurocholate cotransporting polypeptide substrate taurocholic acid. These data indicate that ticagrelor increases rosuvastatin concentrations more than twofold in humans, probably mainly by inhibiting intestinal BCRP. Because the risk for rosuvastatin‐induced myotoxicity increases along with rosuvastatin plasma concentrations, using ticagrelor concomitantly with high doses of rosuvastatin should be avoided.
The association of SLCO1B1 c.521T>C with simvastatin-induced muscle toxicity is well characterized. However, different statins are subject to metabolism and transport also by other proteins ...exhibiting clinically meaningful genetic variation. Our aim was to investigate associations of SLCO1B1 c.521T>C with intolerance to atorvastatin, fluvastatin, pravastatin, rosuvastatin, or simvastatin, those of ABCG2 c.421C>A with intolerance to atorvastatin, fluvastatin, or rosuvastatin, and that of CYP2C9*2 and *3 alleles with intolerance to fluvastatin.
We studied the associations of these variants with statin intolerance in 2042 patients initiating statin therapy by combining genetic data from samples from the Helsinki Biobank to clinical chemistry and statin purchase data.
We confirmed the association of SLCO1B1 c.521C/C genotype with simvastatin intolerance both by using phenotype of switching initial statin to another as a marker of statin intolerance hazard ratio (HR) 1.88, 95% confidence interval (CI) 1.08-3.25, P = 0.025 and statin switching along with creatine kinase measurement (HR 5.44, 95% CI 1.49-19.9, P = 0.011). No significant association was observed with atorvastatin and rosuvastatin. The sample sizes for fluvastatin and pravastatin were relatively small, but SLCO1B1 c.521T>C carriers had an increased risk of pravastatin intolerance defined by statin switching when compared to homozygous reference T/T genotype (HR 2.11, 95% CI 1.01-4.39, P = 0.047).
The current results can inform pharmacogenetic statin prescribing guidelines and show feasibility for the methodology to be used in larger future studies.
Individual assessment of CYP enzyme activities can be challenging. Recently, the potato alkaloid solanidine was suggested as a biomarker for CYP2D6 activity. Here, we aimed to characterize the ...sensitivity and specificity of solanidine as a CYP2D6 biomarker among Finnish volunteers with known CYP2D6 genotypes.
Using non-targeted metabolomics analysis, we identified 9152 metabolite features in the fasting plasma samples of 356 healthy volunteers. Machine learning models suggested strong association between CYP2D6 genotype-based phenotype classes with a metabolite feature identified as solanidine. Plasma solanidine concentration was 1887% higher in genetically poor CYP2D6 metabolizers (gPM) (n = 9; 95% confidence interval 755%, 4515%; P = 1.88 × 10
), 74% higher in intermediate CYP2D6 metabolizers (gIM) (n = 89; 27%, 138%; P = 6.40 × 10
), and 35% lower in ultrarapid CYP2D6 metabolizers (gUM) (n = 20; 64%, - 17%; P = 0.151) than in genetically normal CYP2D6 metabolizers (gNM; n = 196). The solanidine metabolites m/z 444 and 430 to solanidine concentration ratios showed even stronger associations with CYP2D6 phenotypes. Furthermore, the areas under the receiver operating characteristic and precision-recall curves for these metabolic ratios showed equal or better performances for identifying the gPM, gIM, and gUM phenotype groups than the other metabolites, their ratios to solanidine, or solanidine alone. In vitro studies with human recombinant CYP enzymes showed that solanidine was metabolized mainly by CYP2D6, with a minor contribution from CYP3A4/5. In human liver microsomes, the CYP2D6 inhibitor paroxetine nearly completely (95%) inhibited the metabolism of solanidine. In a genome-wide association study, several variants near the CYP2D6 gene associated with plasma solanidine metabolite ratios.
These results are in line with earlier studies and further indicate that solanidine and its metabolites are sensitive and specific biomarkers for measuring CYP2D6 activity. Since potato consumption is common worldwide, this biomarker could be useful for evaluating CYP2D6-mediated drug-drug interactions and to improve prediction of CYP2D6 activity in addition to genotyping.
Aims
Ibrutinib is used in the treatment of certain B‐cell malignancies. Due to its CYP3A4‐mediated metabolism and highly variable pharmacokinetics, it is prone to potentially harmful drug‐drug ...interactions.
Methods
In a randomized, placebo‐controlled, three‐phase crossover study, we examined the effect of the CYP3A4‐inhibiting antifungal posaconazole on ibrutinib pharmacokinetics. Eleven healthy participants ingested repeated doses of 300 mg of posaconazole either in the morning or in the evening, or placebo. A single dose of ibrutinib (30, 70 or 140 mg, respectively) was administered at 9 AM, 1 or 12 h after the preceding posaconazole/placebo dose.
Results
On average, morning posaconazole increased the dose‐adjusted geometric mean area under the plasma concentration‐time curve from zero to infinity (AUC0‐∞) and peak plasma concentration (Cmax) of ibrutinib 9.5‐fold (90% confidence interval CI 6.3‐14.3, P < 0.001) and 8.5‐fold (90% CI 5.7‐12.8, P < 0.001), respectively, while evening posaconazole increased those 10.3‐fold (90% CI 6.7‐16.0, P < 0.001) and 8.2‐fold (90% CI 5.2‐13.2, P < 0.001), respectively. Posaconazole had no significant effect on the half‐life of ibrutinib, but substantially reduced the metabolite PCI‐45227 to ibrutinib AUC0‐∞ ratio. There were no significant differences in ibrutinib pharmacokinetics between morning and evening posaconazole phases.
Conclusions
Posaconazole increases ibrutinib exposure substantially, by about 10‐fold. This interaction cannot be avoided by dosing the drugs 12 h apart. In general, a 70‐mg daily dose of ibrutinib should not be exceeded during posaconazole treatment to avoid potentially toxic systemic ibrutinib concentrations.
Deregulated miRNA expression has been suggested in several stages of breast cancer pathogenesis. We have studied the miR-30 family, in particular miR-30d, in relation to breast cancer patient ...survival and treatment outcomes. With tumor specimens from 1238 breast cancer patients, we analyzed the association of miR-30d expression with tumor characteristics with the 5-year occurrence of breast cancer-specific death or distant metastasis (BDDM), and with 10-year breast cancer survival (BCS). We conducted a two-stage drug-screen to investigate the impact of miR-30 family members (miR-30a-30e) on sensitivity to doxorubicin and lapatinib in six breast cancer cell lines HCC1937, HCC1954, MDA-MB-361, MCF7, MDA-MB-436 and CAL-120, using drug sensitivity scores (DSS) to compare the miR-30 family mimics to their specific inhibitors. The study was complemented with Ingenuity Pathway Analysis (IPA) with the METABRIC data. We found that while high miR-30d expression is typical for aggressive tumors, it predicts better metastasis-free (pBDDM = 0.035, HR = 0.63, 95% CI = 0.4–0.9) and breast cancer-specific survival (pBCS = 0.018, HR = 0.61, 95% CI = 0.4–0.9), especially in HER2-positive (pBDDM = 0.0009), ER-negative (pBDDM = 0.003), p53-positive (pBDDM = 0.011), and highly proliferating (pBDDM = 0.0004) subgroups, and after adjuvant chemotherapy (pBDDM = 0.035). MiR-30d predicted survival independently of standard prognostic markers (pBDDM = 0.0004). In the drug-screening test, the miR-30 family sensitized the HER2-positive HCC1954 cell line to lapatinib (p < 10−2) and HCC1937, MDA-MB-361, MDA-MB-436 and CAL120 to doxorubicin (p < 10−4) with an opposite impact on MCF7. According to the pathway analysis, the miR-30 family has a suppressive effect on cell motility and metastasis in breast cancer. Our results suggest prognostic and predictive potential for the miR-30 family, which warrants further investigation.
Purpose
The
FANCM
c.5101C>T nonsense mutation was previously found to associate with breast cancer in the Finnish population, especially among triple-negative cases. Here, we studied the prevalence ...of three other
FANCM
variants: c.5791C>T, which has been reported to predispose to familial breast cancer, and the c.4025_4026delCT and c.5293dupA variants recently identified in Finnish cancer patients.
Methods
We genotyped the
FANCM
c.5791C>T mutation in 4806 invasive breast cancer patients, including
BRCA1/2
mutation negative familial cases and unselected cases, and in 2734 healthy population controls from four different geographical areas of Finland. The association of the mutation with breast cancer risk among patient subgroups was statistically evaluated. We further analyzed the combined risk associated with c.5101C>T and c.5791C>T mutations. We also genotyped 526 unselected ovarian cancer patients for the c.5791C>T mutation and 862 familial breast cancer patients for the c.4025_4026delCT and c.5293dupA variants.
Results
The frequency of the
FANCM
c.5791C>T mutation was higher among breast cancer cases than in controls (OR 1.94, 95% CI 0.87–4.32,
P
= 0.11), with a statistically significant association with triple-negative breast cancer (OR 5.14, 95% CI 1.65–16.0,
P
= 0.005). The combined analysis for c.5101C>T and c.5791C>T carriers confirmed a strong association with breast cancer (OR 1.86, 95% CI 1.32–2.49,
P
= 0.0002), especially among the triple-negative patients (OR 3.08, 95% CI 1.77–5.35,
P
= 0.00007). For the other variants, only one additional c.4025_4026delCT carrier and no c.5293dupA carriers were observed.
Conclusions
These results support the role of
FANCM
as a breast cancer susceptibility gene, particularly for triple-negative breast cancer.
Purpose The FANCM c.5101C>T nonsense mutation was previously found to associate with breast cancer in the Finnish population, especially among triple-negative cases. Here, we studied the prevalence ...of three other FANCM variants: c.5791C>T, which has been reported to predispose to familial breast cancer, and the c.4025_4026delCT and c.5293dupA variants recently identified in Finnish cancer patients. Methods We genotyped the FANCM c.5791C>T mutation in 4806 invasive breast cancer patients, including BRCA1/2 mutation negative familial cases and unselected cases, and in 2734 healthy population controls from four different geographical areas of Finland. The association of the mutation with breast cancer risk among patient subgroups was statistically evaluated. We further analyzed the combined risk associated with c.5101C>T and c.5791C>T mutations. We also genotyped 526 unselected ovarian cancer patients for the c.5791C>T mutation and 862 familial breast cancer patients for the c.4025_4026delCT and c.5293dupA variants. Results The frequency of the FANCM c.5791C>T mutation was higher among breast cancer cases than in controls (OR 1.94, 95% CI 0.87-4.32, P = 0.11), with a statistically significant association with triple-negative breast cancer (OR 5.14, 95% CI 1.65-16.0, P = 0.005). The combined analysis for c.5101C>T and c.5791C>T carriers confirmed a strong association with breast cancer (OR 1.86, 95% CI 1.32-2.49, P = 0.0002), especially among the triple-negative patients (OR 3.08, 95% CI 1.77-5.35, P = 0.00007). For the other variants, only one additional c.4025_4026delCT carrier and no c.5293dupA carriers were observed. Conclusions These results support the role of FANCM as a breast cancer susceptibility gene, particularly for triple-negative breast cancer.
PDF
