The purposes of this study were to estimate the reduction in risk of ovarian, fallopian tube, or peritoneal cancer in women with a BRCA1 or BRCA2 mutation after oophorectomy, by age of oophorectomy; ...to estimate the impact of prophylactic oophorectomy on all-cause mortality; and to estimate 5-year survival associated with clinically detected ovarian, occult, and peritoneal cancers diagnosed in the cohort.
Women with a BRCA1 or BRCA2 mutation were identified from an international registry; 5,783 women completed a baseline questionnaire and ≥ one follow-up questionnaires. Women were observed until either diagnosis of ovarian, fallopian tube, or peritoneal cancer, death, or date of most recent follow-up. Hazard ratios (HRs) for cancer incidence and all-cause mortality associated with oophorectomy were evaluated using time-dependent survival analyses.
After an average follow-up period of 5.6 years, 186 women developed either ovarian (n = 132), fallopian (n = 22), or peritoneal (n = 32) cancer, of whom 68 have died. HR for ovarian, fallopian, or peritoneal cancer associated with bilateral oophorectomy was 0.20 (95% CI, 0.13 to 0.30; P < .001). Among women who had no history of cancer at baseline, HR for all-cause mortality to age 70 years associated with an oophorectomy was 0.23 (95% CI, 0.13 to 0.39; P < .001).
Preventive oophorectomy was associated with an 80% reduction in the risk of ovarian, fallopian tube, or peritoneal cancer in BRCA1 or BRCA2 carriers and a 77% reduction in all-cause mortality.
Tumor-driven immune suppression is a major barrier to successful immunotherapy in ovarian carcinomas (OvCa). Among various mechanisms responsible for immune suppression, arginase-1 (ARG1)-carrying ...small extracellular vesicles (EVs) emerge as important contributors to tumor growth and tumor escape from the host immune system. Here, we report that small EVs found in the ascites and plasma of OvCa patients contain ARG1. EVs suppress proliferation of CD4
and CD8
T-cells in vitro and in vivo in OvCa mouse models. In mice, ARG1-containing EVs are transported to draining lymph nodes, taken up by dendritic cells and inhibit antigen-specific T-cell proliferation. Increased expression of ARG1 in mouse OvCa cells is associated with accelerated tumor progression that can be blocked by an arginase inhibitor. Altogether, our studies show that tumor cells use EVs as vehicles to carry over long distances and deliver to immune cells a metabolic checkpoint molecule - ARG1, mitigating anti-tumor immune responses.
Ovarian cancer has a high recurrence and mortality rate. A barrier to improved outcomes includes a lack of accurate models for preclinical testing of novel therapeutics.
Clinically relevant, ...patient-derived tumorgraft models were generated from sequential patients and the first 168 engrafted models are described. Fresh ovarian, primary peritoneal, and fallopian tube carcinomas were collected at the time of debulking surgery and injected intraperitoneally into severe combined immunodeficient mice.
Tumorgrafts demonstrated a 74% engraftment rate with microscopic fidelity of primary tumor characteristics. Low-passage tumorgrafts also showed comparable genomic aberrations with the corresponding primary tumor and exhibit gene set enrichment of multiple ovarian cancer molecular subtypes, similar to patient tumors. Importantly, each of these tumorgraft models is annotated with clinical data and for those that have been tested, response to platinum chemotherapy correlates with the source patient.
Presented herein is the largest known living tumor bank of patient-derived, ovarian tumorgraft models that can be applied to the development of personalized cancer treatment.
Resistance to platinum-based chemotherapy or PARP inhibition in germline
or
mutation carriers may occur through somatic reversion mutations or intragenic deletions that restore BRCA1 or BRCA2 ...function. We assessed whether
reversion mutations could be identified in circulating cell-free DNA (cfDNA) of patients with ovarian or breast cancer previously treated with platinum and/or PARP inhibitors.
cfDNA from 24 prospectively accrued patients with germline
or
mutations, including 19 patients with platinum-resistant/refractory ovarian cancer and five patients with platinum and/or PARP inhibitor pretreated metastatic breast cancer, was subjected to massively parallel sequencing targeting all exons of 141 genes and all exons and introns of
and
Functional studies were performed to assess the impact of the putative
reversion mutations on BRCA1/2 function.
Diverse and often polyclonal putative
or
reversion mutations were identified in cfDNA from four patients with ovarian cancer (21%) and from two patients with breast cancer (40%).
reversion mutations were detected in cfDNA prior to PARP inhibitor treatment in a patient with breast cancer who did not respond to treatment and were enriched in plasma samples after PARP inhibitor therapy. Foci formation and immunoprecipitation assays suggest that a subset of the putative reversion mutations restored BRCA1/2 function.
Putative
reversion mutations can be detected by cfDNA sequencing analysis in patients with ovarian and breast cancer. Our findings warrant further investigation of cfDNA sequencing to identify putative
reversion mutations and to aid the selection of patients for PARP inhibition therapy.
.
In SOLO1/GOG 3004 (ClinicalTrials.gov identifier: NCT01844986), maintenance therapy with the poly(ADP-ribose) polymerase inhibitor olaparib provided a sustained progression-free survival benefit in ...patients with newly diagnosed advanced ovarian cancer and a
and/or
(BRCA) mutation. We report overall survival (OS) after a 7-year follow-up, a clinically relevant time point and the longest follow-up for any poly(ADP-ribose) polymerase inhibitor in the first-line setting.
This double-blind phase III trial randomly assigned patients with newly diagnosed advanced ovarian cancer and a BRCA mutation in clinical response to platinum-based chemotherapy to maintenance olaparib (n = 260) or placebo (n = 131) for up to 2 years. A prespecified descriptive analysis of OS, a secondary end point, was conducted after a 7-year follow-up.
The median duration of treatment was 24.6 months with olaparib and 13.9 months with placebo, and the median follow-up was 88.9 and 87.4 months, respectively. The hazard ratio for OS was 0.55 (95% CI, 0.40 to 0.76;
= .0004
< .0001 required to declare statistical significance). At 7 years, 67.0% of olaparib patients versus 46.5% of placebo patients were alive, and 45.3% versus 20.6%, respectively, were alive and had not received a first subsequent treatment (Kaplan-Meier estimates). The incidence of myelodysplastic syndrome and acute myeloid leukemia remained low, and new primary malignancies remained balanced between treatment groups.
Results indicate a clinically meaningful, albeit not statistically significant according to prespecified criteria, improvement in OS with maintenance olaparib in patients with newly diagnosed advanced ovarian cancer and a BRCA mutation and support the use of maintenance olaparib to achieve long-term remission in this setting; the potential for cure may also be enhanced. No new safety signals were observed during long-term follow-up.
Purpose AZD1775 is a first-in-class, potent, and selective inhibitor of WEE1 with proof of chemopotentiation in p53-deficient tumors in preclinical models. In a phase I study, the maximum tolerated ...dose of AZD1775 in combination with carboplatin demonstrated target engagement. We conducted a proof-of-principle phase II study in patients with p53 tumor suppressor gene ( TP53)-mutated ovarian cancer refractory or resistant (< 3 months) to first-line platinum-based therapy to determine overall response rate, progression-free and overall survival, pharmacokinetics, and modulation of phosphorylated cyclin-dependent kinase (CDK1) in skin biopsies. Patients and Methods Patients were treated with carboplatin (area under the curve, 5 mg/mL⋅min) combined with AZD1775 225 mg orally twice daily over 2.5 days every 21-day cycle until disease progression. Results AZD1775 plus carboplatin demonstrated manageable toxicity; fatigue (87%), nausea (78%), thrombocytopenia (70%), diarrhea (70%), and vomiting (48%) were the most common adverse events. The most frequent grade 3 or 4 adverse events were thrombocytopenia (48%) and neutropenia (37%). Of 24 patients enrolled, 21 patients were evaluable for efficacy end points. The overall response rate was 43% (95% CI, 22% to 66%), including one patient (5%) with a prolonged complete response. Median progression-free and overall survival times were 5.3 months (95% CI, 2.3 to 9.0 months) and 12.6 months (95% CI, 4.9 to 19.7), respectively, with two patients with ongoing response for more than 31 and 42 months at data cutoff. Conclusion To our knowledge, this is the first report providing clinical proof that AZD1775 enhances carboplatin efficacy in TP53-mutated tumors. The encouraging antitumor activity observed in patients with TP53-mutated ovarian cancer who were refractory or resistant (< 3 months) to first-line therapy warrants further development.
The adipocyte-rich microenvironment forms a niche for ovarian cancer metastasis, but the mechanisms driving this process are incompletely understood. Here we show that salt-inducible kinase 2 (SIK2) ...is overexpressed in adipocyte-rich metastatic deposits compared with ovarian primary lesions. Overexpression of SIK2 in ovarian cancer cells promotes abdominal metastasis while SIK2 depletion prevents metastasis in vivo. Importantly, adipocytes induce calcium-dependent activation and autophosphorylation of SIK2. Activated SIK2 plays a dual role in augmenting AMPK-induced phosphorylation of acetyl-CoA carboxylase and in activating the PI3K/AKT pathway through p85α-S154 phosphorylation. These findings identify SIK2 at the apex of the adipocyte-induced signaling cascades in cancer cells and make a compelling case for targeting SIK2 for therapy in ovarian cancer.
Display omitted
•SIK2 is highly expressed in adipocyte-rich metastases•SIK2 is required for adipocyte-induced proliferation of ovarian cancer metastasis•SIK2 promotes ovarian cancer cell fatty acid oxidation through ACC phosphorylation•SIK2 activates the PI3K pathway through phosphorylation of p85α at S154 and S541
Miranda et al. show that in serous ovarian cancer SIK2 is overexpressed in adipocyte-rich metastatic deposits compared with primary lesions. Adipocytes induce calcium-dependent activation and autophosphorylation of SIK2, which drives tumor cell survival and metabolism. SIK2 depletion prevents metastasis in vivo.
We studied the whole-genome point mutation and structural variation patterns of 133 tumors (59 high-grade serous (HGSC), 35 clear cell (CCOC), 29 endometrioid (ENOC), and 10 adult granulosa cell ...(GCT)) as a substrate for class discovery in ovarian cancer. Ab initio clustering of integrated point mutation and structural variation signatures identified seven subgroups both between and within histotypes. Prevalence of foldback inversions identified a prognostically significant HGSC group associated with inferior survival. This finding was recapitulated in two independent cohorts (n = 576 cases), transcending BRCA1 and BRCA2 mutation and gene expression features of HGSC. CCOC cancers grouped according to APOBEC deamination (26%) and age-related mutational signatures (40%). ENOCs were divided by cases with microsatellite instability (28%), with a distinct mismatch-repair mutation signature. Taken together, our work establishes the potency of the somatic genome, reflective of diverse DNA repair deficiencies, to stratify ovarian cancers into distinct biological strata within the major histotypes.
Mitochondria undergo fission and fusion continually for survival through the course of cellular adaption processes in response to changes in the surrounding environment. Dysregulated mitochondrial ...dynamics has been reported in various diseases including cancer. Under hypoxic conditions (<1% O
), the relationship between mitochondrial dynamics and sensitivity to cisplatin (CDDP) was examined in ovarian cancer cells. We found that hypoxia promoted mitochondrial fission and CDDP resistance in ovarian cancer cells. Hypoxia-induced reactive oxygen species (ROS) caused an increase in mitochondrial fission, a response abolished by free radical scavenging with N-acetylcysteine (NAC) and Trolox. Also, treatment of hydrogen peroxide (H
O
) decreased inhibitory p-Drp1 (Ser637) content and increased mitochondrial fission. Suppression of mitochondrial fission enhanced the CDDP sensitivity of hypoxic ovarian cancer cells. Lastly, in tumor spheroids from malignant ascites or tissues of patients with advanced-stage ovarian cancer, pretreatment with Mdivi-1 increased the CDDP sensitivity. Taken together, our results implicate that hypoxia-induced ROS trigger mitochondrial fission and CDDP resistance through downregulation of p-Drp1 (Ser637) and Mfn1 in ovarian cancer cells. Inhibition of Drp1 by Mdivi-1 treatment or si-Drp1 transfection increased CDDP sensitivity of ovarian cancer cells under hypoxia. Therefore, mitochondrial dynamics of cancer cells adapting to the hypoxic tumor microenvironment could be a potential target for anticancer therapy.
PDF
