Circulating microRNAs in lung cancer: prospects for diagnosis, prognosis, and prediction of antitumor treatment efficacy

The review considers the main techniques to extract microRNA (miRNA) from various biological fluids (in particular, the serum and plasma), approaches to the analysis of miRNA concentration and composition, and methods to normalize the results in data analyses. Advantages and drawbacks of the methods are described. Special attention is given to circulating miRNAs, which can be used as markers for minimally invasive diagnosis, prediction of antitumor treatment efficacy, and disease prognosis in lung cancer. The review discusses the prospects and limitations that arise as the clinical significance is evaluated for miRNAs as potential tumor markers and a better understanding is gained for the roles various miRNAs play in the pathogenesis of lung cancer

Cell-free and cell-bound circulating DNA in breast tumours: DNA quantification and analysis of tumour-related gene methylation

Tumour development is characterised by the increased circulating DNA (cirDNA) concentration and by tumour-related changes in blood plasma DNA. Concentration of cirDNA and methylation of RARβ2, RASSF1A and HIC-1 gene promoters were investigated in cell-free and cell-surface-bound fractions from healthy donors, patients with breast cancer, and patients with breast fibroadenoma. Tumour development was shown to lead to significant changes in the distribution of cirDNA between cell-free and cell-surface-bound fractions. Analysis of RARβ2 and RASSF1A methylation in the total cirDNA provides 95% diagnostic coverage in breast cancer patients, 60% in patients with benign lesions, and is without false-positive results in healthy women. Results of the study indicate that methylation-specific PCR of RARβ2 and RASSF1A genes based on the total cirDNA combined with the quantitative analysis of cirDNA distribution between cell-bound and cell-free fractions in blood provide the sensitive and accurate detection and discrimination of malignant and benign breast tumours

The clinical and morphological features of ovarian steroid cell tumors

Ovarian steroid cell tumors are rare, unusual neoplasms. There is now no unified management tactics for patients with this pathology. The paper reviews the literature on the clinical and morphological characteristics, prognostic factors, diagnosis, and treatme nt in patients with ovarian steroid cell tumors

Circulating DNA-markers in lung cancer: changes in retrotrasposons methylation status in response therapy and during the post-treatment follow-up

Malignant cell transformation is accompanied by two processes of DNA methylation changes

Genome-wide analysis of gene regulation mechanisms during Drosophila spermatogenesis

Background During Drosophila spermatogenesis, testis-specific meiotic arrest complex (tMAC) and testis-specific TBP-associated factors (tTAF) contribute to activation of hundreds of genes required for meiosis and spermiogenesis. Intriguingly, tMAC is paralogous to the broadly expressed complex Myb-MuvB (MMB)/dREAM and Mip40 protein is shared by both complexes. tMAC acts as a gene activator in spermatocytes, while MMB/dREAM was shown to repress gene activity in many cell types. Results Our study addresses the intricate interplay between tMAC, tTAF, and MMB/dREAM during spermatogenesis. We used cell type-specific DamID to build the DNA-binding profiles of Cookie monster (tMAC), Cannonball (tTAF), and Mip40 (MMB/dREAM and tMAC) proteins in male germline cells. Incorporating the whole transcriptome analysis, we characterized the regulatory effects of these proteins and identified their gene targets. This analysis revealed that tTAFs complex is involved in activation of achi, vis, and topi meiosis arrest genes, implying that tTAFs may indirectly contribute to the regulation of Achi, Vis, and Topi targets. To understand the relationship between tMAC and MMB/dREAM, we performed Mip40 DamID in tTAF- and tMAC-deficient mutants demonstrating meiosis arrest phenotype. DamID profiles of Mip40 were highly dynamic across the stages of spermatogenesis and demonstrated a strong dependence on tMAC in spermatocytes. Integrative analysis of our data indicated that MMB/dREAM represses genes that are not expressed in spermatogenesis, whereas tMAC recruits Mip40 for subsequent gene activation in spermatocytes. Conclusions Discovered interdependencies allow to formulate a renewed model for tMAC and tTAFs action in Drosophila spermatogenesis demonstrating how tissue-specific genes are regulated

Dynamics of LINE-1 retrotransposon methylation levels in circulating DNA from lung cancer patients undergoing antitumor therapy

Malignant cell transformation is accompanied with abnormal DNA methylation, such as the hypermethylation of certain gene promoters and hypomethylation of retrotransposons. In particular, the hypomethylation of the human-specific family of LINE-1 retrotransposons was observed in lung cancer tissues. It is also known that the circulating DNA (cirDNA) of blood plasma and cell-surface-bound circulating DNA (csb-cirDNA) of cancer patients accumulate tumor-specific aberrantly methylated DNA fragments, which are currently considered to be valuable cancer markers. This work compares LINE-1 retrotransposon methylation patterns in cirDNA of 16 lung cancer patients before and after treatment. CirDNA was isolated from blood plasma, and csb-cirDNA fractions were obtained by successive elution with EDTA-containing phosphate buffered saline and trypsin. Concentrations of methylated LINE-1 region 1 copies (LINE-1-met) were assayed by real-time methylation-specific PCR. LINE-1 methylation levels were normalized to the concentration of LINE-1 region 2, which was independent of the methylation status (LINE-1-Ind). The concentrations of LINE-1-met and LINE-1-Ind in csb-cirDNA of lung cancer patients exhibited correlations before treatment (r = 0.54), after chemotherapy (r = 0.72), and after surgery (r = 0.83) (P 0.05, respectively). These results suggest a need for the further investigation of dynamic changes in levels of LINE-1 methylation depending on the antitumor therapy

Prognostic value of the proportion of the sclerosing component in fibrolamellar liver carcinoma

Introduction. Fibrolamellar hepatocellular carcinoma (FLC), which develops most often in the younger population. In FLC, variable histoarchitectonics are noted, possibly the presence of a sclerosing component, foci of necrosis and dystrophy of tumor cells.Objective. Assessment of the influence of the proportion of the sclerosing component in fibrolamellar carcinoma (FLC) of the liver on the course and prognosis of the disease. Determination of the relationship between the proportion of the sclerosing component in the tumor and the frequency of microvascular invasion.Materials and methods. A retrospective study included 34 patients with a diagnosis of FLC, who underwent radical surgical treatment at the first stage. A histological assessment of the proportion (%) of the sclerosing component in FLC was made. The effect of  the  proportion of  the  sclerosing component on overall (OS) and relapse-free (DFS) survival was assessed. The  analysis of the relationship between the proportion of the sclerosing component in the tumor and the frequency of microvascular invasion was carried out.Results. Significantly worse RFS was achieved in the groups of patients with a sclerosing component in FLC > 5% than in the group of patients with a sclerosing component in FLC ≤ 5% (p = 0.0010; p = 0.024; log – rank test). Median DDS in group 1 is 107 (95% CI, 22–192) months; at 2 – 11 (95% CI, 8–14) months; in 3 – 21 (95% CI, 8–33). The frequency of histologically confirmed microvascular invasion in the compared groups was 29, 74, 87.5%, respectively. OS was significantly worse in 2 groups (27 patients in total) with a sclerosing component in FLC > 5% than in the group of patients with a sclerosing component in FLC ≤ 5%. Median OS in group 1 120 (95% CI, 60–180) months; at 2 – 41 (95% CI, 15–92) months; in 3 – 69 (95% CI, 35–103). A direct relationship was found between an increase in the proportion of the sclerosing component in a tumor and an increase in the frequency of microvascular invasion.Conclusions. We can assume that the severity of the sclerosing component in the FLK tumor can serve as an effective morphological marker of a less favorable prognosis for this HCC subtype and correlate with the frequency of microvascular invasion

Resolution on the results of Advisory Board “Searching the effective methods of testing and treating patients with NSCLC caused by <i>NTRK</i> gene fusions“

The Advisory Board was held on December 24, 2021. The molecular genetic research lead specialists and national lead oncologists discussed issues of diagnosis of NTRK gene translocations in patients with non-small cell lung cancer (NSCLC), as well as current opportunities for the treatment of patients with NSCLC caused by NTRK gene fusions. The experts reaffirmed the necessity to identify timely patients with NSCLC caused by NTRK gene fusions, as the correct diagnosis of the disease, including the use of modern diagnostic methods of NTRK gene fusion (NGS is the most sensitive and specific method) determines the success of patient treatment. In this regard, it is critical that physicians know the advantages and disadvantages of each molecular diagnostic method used to have the opportunity to choose the best approach in each clinical case. In order to have a clear, well-functioning strategy for managing patients with suspected NSCLC caused by NTRK gene fusion, it is necessary to use molecular genetic tests, as well as include TRK inhibitors (in particular, the drug larotrectinib; at the time publication of the Resolution, the drug larotrectinib is not registered in the territory of the Russian Federation) in the clinical guidelines for the treatment of lung cancer. Larotrectinib is a highly selective tropomyosin receptor kinase (TRK) inhibitor. The clinical studies on larotrectinib have demonstrated high response rates and durable responses in adults and children with tumours associated with NTRK gene fusions, including primary CNS tumours and brain metastases. The objective response rate observed with larotrectinib was 79%, with 16% achieving a complete response and 64% achieving a partial response. At the same time, the median progression-free survival on larotrectinib was 28.3 months, and the median overall survival was 44.4 months

ИММУНООПОСРЕДОВАННЫЕ НЕЖЕЛАТЕЛЬНЫЕ ЯВЛЕНИЯ, СВЯЗАННЫЕ С ЛЕЧЕНИЕМ ПРЕПАРАТАМИ, БЛОКИРУЮЩИМИ КОНТРОЛЬНЫЕ ТОЧКИ Т-ЛИМФОЦИТОВ

In recent years, immunotherapy is the main emphasis approach for malignant tumors treatment due to the development and registration of a new class of drugs –immune checkpoint inhibitors. Results of the randomized clinical trials, which showed a benefit in overall survival in comparison with standard therapy, was the basis for registration of this class of medicines [1–3]. Their toxicity profile is more favorable. However, the adverse reactions, which accrues during immunotherapy, are essentially new and different from standard chemotherapy. The standard management algorithm compensates the variety of immunemediated adverse reactions [4]. Early detection and timely treatment is necessary for the successful management of these adverse reactions. В последние годы основной акцент в лекарственном лечении злокачественных опухолей делается на иммунотерапию.Это обусловлено разработкой и регистрацией нового класса препаратов – блокаторов контрольных точек иммунного пути. Основанием для регистрации этого класса препаратов послужили результаты рандомизированных клинических исследований, показавших преимущество этих препаратов по сравнению со стандартной терапией в общей выживаемости [1–3]. Более благоприятным оказался их токсический профиль. Однако те осложнения, с которыми пришлось столкнуться клиницистам, имели принципиально новый, отличный от обусловленных стандартными цитостатиками характер. Многообразие побочных иммуноопосредованных реакций компенсируется стандартным алгоритмом их коррекции [4]. Раннее выявление и своевременное лечение необходимо для успешного купирования этих осложнений