Tyrosyl-DNA phosphodiesterase 1 (TDP1) catalyzes the cleavage of the phosphodiester bond between the tyrosine residue of topoisomerase 1 (TOP1) and the 3' phosphate of DNA in the single-strand break ...generated by TOP1. TDP1 promotes the cleavage of the stable DNA-TOP1 complexes with the TOP1 inhibitor topotecan, which is a clinically used anticancer drug. This article reports the synthesis and study of usnic acid thioether and sulfoxide derivatives that efficiently suppress TDP1 activity, with IC
values in the 1.4-25.2 μM range. The structure of the heterocyclic substituent introduced into the dibenzofuran core affects the TDP1 inhibitory efficiency of the compounds. A five-membered heterocyclic fragment was shown to be most pharmacophoric among the others. Sulfoxide derivatives were less cytotoxic than their thioester analogs. We observed an uncompetitive type of inhibition for the four most effective inhibitors of TDP1. The anticancer effect of TOP1 inhibitors can be enhanced by the simultaneous inhibition of PARP1, TDP1, and TDP2. Some of the compounds inhibited not only TDP1 but also TDP2 and/or PARP1, but at significantly higher concentration ranges than TDP1. Leader compound
showed promising synergy on HeLa cells in conjunction with the TOP1 inhibitor topotecan.
Clinical trials of targeted therapy (TT) and immunotherapy (IT) for highly aggressive advanced melanoma have shown marked improvements in response and survival rates. However, real-world data on ...treatment patterns and clinical outcomes for patients with advanced BRAF V600 mutant melanoma are ultimately scarce. The study was designed as an observational retrospective chart review study, which included 382 patients with advanced BRAF V600 mutant melanoma, who received TT in a real-world setting and were not involved in clinical trials. The data were collected from twelve medical centers in Russia. The objective response rates (ORRs) to combined BRAFi plus MEKi and to BRAFi mono-therapy were 57.4% and 39.8%, respectively. The median progression-free survival (PFS) and median overall survival (OS) were 9.2 months and 22.6 months, respectively, for the combined first-line therapy; 9.4 months and 16.1 months, respectively, for the combined second-line therapy; and 7.4 months and 17.1 months, respectively, for the combined third- or higher-line therapy. Analysis of treatment patterns demonstrated the effectiveness of the combined TT with BRAF plus MEK inhibitors in patients with brain metastases, rare types of BRAF mutations, and across lines of therapy, as well as a well-tolerated and manageable safety profile.
Background. According to current clinical guidelines, patients with inoperable and/or metastatic melanoma (IMM) should undergo a molecular genetic study for the presence of mutations in the BRAF V600 ...gene in order to select drug therapy. Its accessibility and timing may vary in the regions of Russia. Aim. To assess the possibility, accessibility, and timing of a molecular genetic study for melanoma in Russia. Results. From November 15, 2023, to December 11, 2023, a survey was conducted, which included 32 respondents (oncologists and heads of depart- ments/laboratories) from various federal districts, where 1 to 1000 IMM patients are being diagnosed and treated annually. A mutation in the BRAF gene was detected in 79,1% of patients. The duration of the study was about 15 (3-35) days. The mutations were detected in a local institution in 60% of cases, within the Russian Society of Clinical Oncology diagnostic program in 21,1%, and in other programs in 18,9%. Conclusion. The wide accessibility of the detection of BRAF gene mutations in the Russian Federation was reported due to the following factors: the introduction of molecular genetic diagnostics programs, in particular the Russian Society of Clinical Oncology program, as well as other programs sponsored by pharmaceutical companies and the possibility of testing under a compulsory health insurance policy. However, approximately 21% (20,9%) of patients with IMM do not test for mutations in the BRAF gene, even if they have their own laboratory in the institution. It is crucial to test all patients with melanoma from stage III onwards for BRAF mutations, especially when treatment is started with immunotherapy and there is enough time for the BRAF mutation result to be routinely obtained.
•A microarray-based method was evaluated to identify ctDNA BRAF mutations in melanoma patients.•The presence of BRAF mutations in cfDNA correlates with tumor progression (P=0.005).•Increased levels ...of cfDNA correlate with tumor progression (P=0.02).•Coincidence of genotypes between the tumor DNA and ctDNA was 65%.
Background: Circulating tumor DNA (ctDNA) holds great potential for cancer therapy and can provide diagnostic and prognostic information before and during treatment.
Methods: Plasma DNA samples from 97 melanoma patients, 20 healthy donors and 3 patients with benign skin tumors were analyzed by microarray analysis and droplet digital PCR (ddPCR).
Results: A microarray for simultaneous detection of six BRAF V600 mutations in ctDNA has been developed. The method allows the detection of 0.05% mutated DNA from WT DNA background. For paired samples (pre-surgery plasma and tumor tissue) isolated from 74 patients, the concordance of genotypes between tumor DNA and ctDNA was 65% (48/74). BRAF mutations in ctDNA were detected in 27/50 patients with BRAF-positive tumors and in 3/24 patients with BRAF wild-type tumors. The presence of ctDNA BRAF mutations in 23 plasma samples from melanoma patients undergoing therapy correlated significantly with tumor progression (P=0.005). The increase in cell-free DNA levels measured by ddPCR also correlated with disease progression (P=0.02). The concordance of results obtained by microarray identification of BRAF mutations and those obtained by ddPCR was 91%.
Conclusion: The novel microarray-based approach can be a useful non-invasive tool for accurate identification of ctDNA BRAF mutations to monitor disease progression.
A giant congenital melanocytic nevus (GCMN) is found in 0.1% of live-born infants. If present, the lesion has a chance of about 6% to develop into malignant melanoma. Both children and adults can be ...affected by malignant melanoma arising in a giant congenital nevus. Up to 95% of GCMNs harbor NRAS mutations, and mutations in the BRAF, MC1R, TP53, and GNAQ genes have also been described. The individualization of therapy is required, but diagnostic and prognostic criteria remain controversial.
We report two cases: 1) melanoma arising in a giant congenital nevus during the first month of life complicated with neurocutaneous melanosis (NCM), and 2) melanoma arising in a giant congenital nevus during the first 6 months of life. Pathology, immunohistochemistry, and genetic analyses of tumor tissue were performed. The first case revealed only a non-pathogenic P72R polymorphism of the TP53 gene in the homozygote condition. For the second case, a Q61K mutation was detected in the NRAS gene.
Malignant melanoma associated with GCMN is rare and therefore poorly understood. Outcomes have been linked to the stage at diagnosis, but no additional pathological prognostic factors have been identified. The most frequent genetic event in giant CMNs is NRAS mutations, which was discovered in one of our cases. To accumulate evidence to improve disease prognosis and outcomes, children with congenital melanocytic nevus should be included in a systemic follow-up study from birth.
Background. The need to use BRAF and MEK inhibitors in the treatment of patients with metastatic and/or unresectable BRAF + melanoma in certain clinical situations is beyond doubt nowadays. The ...medical community need more information about the new combination of targeted therapy approved in Russia, further details on the expected efficacy and tolerability, potential differences from the existing combinations.
Aim. To present of the study results and demonstration of our experience with the new generation of targeted therapy encorafenib and binimetinib combination in the treatment of patients with metastatic and/or inoperable BRAF+ melanoma.
Materials and methods. We present the clinical case of BRAF+ advanced melanoma patient with multiple metastases in the liver, spleen, mediastinal and abdominal lymph nodes, stomach and bones who is being treated with encorafenib and binimetinib since 2015 with the treatment efficacy and tolerability described in details, as well as the published data on the efficacy and tolerability of this combination from the pivotal phase III study COLUMBUS.
Results. High immediate and long-term efficacy, satisfactory tolerability of encorafenib and binimetinib combination are presented. Updated data on progression-free and overall survival in the COLUMBUS study confirmed the long-term efficacy of COMBO450 therapy in patients with advanced melanoma with BRAF V600 mutation.
Conclusion. New generation of BRAFi and MEKi combination expands options of systemic therapy for patients with metastatic and/or inoperable BRAF+ melanoma.
Approximately 15% of acral and mucous melanomas carry activating mutations in KIT oncogene. There is a diversity of spectrum of KIT mutations, with some of them rendering tumors responsive to ...imatinib, while others being imatinib-resistant or not studied yet. Here we present an acral melanoma patient with KIT р.T632I mutation, who failed to respond to imatinib.
e21558 Background: Targeted therapy (TT) and anti-PD1 immunotherapy (IT) are standard of adjuvant stage III melanoma treatment. However, no comparative prospective randomized trials (head-to-head) ...were conducted. Data limited to a few retrospective studies. Both treatment regimens were registered in Russia in 2019. We aimed to compare adjuvant options in Russian melanoma pts. Methods: We conducted a single-center retrospective observational study approved by the IRB. We included all pts age 18 and older (one patient, female, was 14) with BRAF-mutated stage III melanoma who were treated at the N.N.Blokhin NMRC of Oncology MoH and received adjuvant therapy between Jan 2019 and Dec 2022. The primary endpoint was RFS, the secondary endpoint - OS. Cox regression analysis was used to identify prognostic factors for RFS (including substage, thickness and ulceration of primary tumor). Results: A total of 209 pts were included, mostly BRAF V600E/K, 92 (44%) male and 117 (56%) female. Median age was 50,6 years (range: 14-81). 93 (44,4%) pts received TT, 103 (49,3%) pts received IT and 13 (6,3%) didn’t receive adjuvant therapy (observation only). The observation group wasn’t analyzed due to a small number of pts. At a median follow-up of 27 mo, median RFS was 30 mo (95% CI 23-56) in TT group and wasn’t reached in IT group; median OS wasn’t reached in both groups. There weren’t statistical differences between TT and IT groups in RFS (HR 0,84, 95% CI 0,53-1,34, p = 0,47) and OS (HR 0,59, 95% CI 0,26-1,34, p = 0,21), even though at 12 mo, the rate of RFS was higher in the TT group (91.4%) compared IT group (67%), at 18 mo – 79,5% and 63,1%, 24 mo – 68,8% and 61,1% respectively. TT group had numeric but not significant RFS benefit in most subgroups. HR values for substage, thickness and ulceration are presented in the table below. Tx+T0 pts (TT, n = 7; IT, n = 13) and unknown status of ulceration (TT, n = 7; IT, n = 16) was not presented for some pts. Conclusions: Differences between TT and IT wasn't reached at a median follow-up of 27 mo. But IT-treated pts had more and earlier recurrences than TT pts. In BRAF mutated pts, adjuvant TT might prevent early recurrences more effectively than IT. These results need to be interpreted with caution given its retrospective and non-randomized nature and potential selection biases. Additional time to follow-up and biomarker analysis was planned. Table: see text
e21573
Background: Mutation in BRAF is a crucial biomarker for treatment choice in patient with locally advanced or metastatic melanoma. In patient with BRAF wild-type (WT) melanoma aPD1 is the ...preferred treatment regimen. In patients with BRAF V600 mutant melanoma combined targeted therapy (cTT) could also be chosen as adjuvant treatment, which significantly improves OS. Methods: We conducted a retrospective continuous study of all melanoma patients, who were tested for BRAF mutation by RT-PCR in 2020 (COIVD-19 pandemic year) in our institution and analyzed adjuvant therapy options they received. Patient demographics, mutational status, disease stage, treatment regimens and treatment outcomes were collected from electronic medical records. Results: Between January 2020 and December 2020, tumor samples from 297 pts were tested for BRAF mutations. The mean pts age was 58.2 years (95% CI 51.2 to 60.3) and 130 (43.7%) were male. BRAF mutations were detected in 147 (49.5%) patients. Most common mutation was V600E (140 out of 147 samples, 88.4%) and V600K (13 out of 147, 8.84%). We also found K601N, K601E, L597R and V600M mutations (in one sample each). Among 150 BRAF wild type samples 44 were also tested for NRAS mutations and in 13 (29.54%) pts NRAS mutations were detected: Q61R – in 6 (46.15%) pts, Q61L – in 2 (15.38%) pts, Q61K – in 3 (23.08%) pts, G12E – in 1 (7.69%) pt, and G12D - in 1 (7.69%) pt . Also among 150 BRAF wild type samples 56 were tested for KIT mutations and only one sample were found to harbour D186V mutation . Among BRAF-positive pts at time of the genetic test performed stage I CM had 11 (7.48%) out of 147 pts, stage II - 13 (8.84%) pts, stage III - 67 (45.57%) pts, and stage IV - 43 (29.25%) pts. In 13 (8.84%) pts stage could not be clearly identified. In most cases (32 out of 67, 47.76%) monotherapy with aPD1 was given as adjuvant treatment in stage III pts where as only 6 (8.95%) patients received cTT, 7 pts (10.41%) received IFN-alfa and 22 pts (32.84%) received no or were given with other treatment (Table). Median DFS did not differ significantly between treatment cohorts. Conclusions: In our retrospective study we found that among stage III BRAF-mutant patients monotherapy with aPD1 was the most common adjuvant treatment regimen. In some patients with stage III disease IFN-alfa is still given. More studies are needed to define best adjuvant treatment for BRAF mutant stage III melanoma pts.Table: see text
e21512
Background: Improved overall survival in patients undergoing metаstasectomy for melanoma have been reported in several retrospective studies before era of modern therapy in melanoma. Rapid ...progress in BRAF and MEK targeted therapy (TT) and immunotherapy (IT) has led to significant improvements in objective response rates and survival rates in advanced melanoma patients. Unfortunately, part of patients have a resistance to modern therapy in one or more lesions. In 2019 Nelson DW et al published data when surgery followed by modern therapy in 47 matched pairs was associated with higher 5-year melanoma-specific survival (MSS) versus modern therapy alone (58.8% vs. 38.9%, p = 0.049). But data about modern therapy in BRAF + advanced melanoma with metastasectomy during therapy are limited. Methods: We conducted an observational retrospective chart review study and evaluated a subset of patients which underwent surgery (metastasectomy) with V600 BRAF-mutant advanced melanoma, who received therapy in a real-world setting in Russia. Survival analyses were performed using the Kaplan-Meier method, Log-rank, chi-square and Fisher exact tests were used for comparison between groups. Results: The observed population included 382 patients in Russia. The date of the first enrollment after all approvals was 8 October 2018, and the date of the last completed register was 27 April 2019. Among 382 patients, 107 (28%) patients received surgical treatment for advanced melanoma during modern therapy (removal of metastases from the brain, lungs, soft tissues and other organs). Surgery during first line therapy was performed in 60pts (56%), as second – in 25pts (23.4%) and third or higher line in 22pts (20.6%). Comparison of overall survival curves for all patients depending on the surgical treatment showed that the survival in the subgroup of patients with the presence of surgical treatment was higher than among patients who did not undergo metastasectomy: 24-months OS was 76.7 (95%CI, 65.6 – 84.6) and 53.7% (95%CI, 46.4-60.4), p = 0,0027). Conclusions: Our findings suggest that resection of distant metastases associated with improved overall survival despite all limitations in retrospective nature of the study. While modern systemic therapy have improved outcomes in advanced melanoma, metastasectomy remains associated with favorable survival. Surgery have to be a part of multidisciplinary care for patients with advanced melanoma.
PDF
