The impact of molecular tumor profiling on the design strategies for targeting myeloid leukemia and EGFR/CD44-positive solid tumors.

Nanomedicine has emerged as a novel cancer treatment and diagnostic modality, whose design constantly evolves towards increasing the safety and efficacy of the chemotherapeutic and diagnostic protocols. Molecular diagnostics, which create a great amount of data related to the unique molecular signatures of each tumor subtype, have emerged as an important tool for detailed profiling of tumors. They provide an opportunity to develop targeting agents for early detection and diagnosis, and to select the most effective combinatorial treatment options. Alongside, the design of the nanoscale carriers needs to cope with novel trends of molecular screening. Also, multiple targeting ligands needed for robust and specific interactions with the targeted cell populations have to be introduced, which should result in substantial improvements in safety and efficacy of the cancer treatment. This article will focus on novel design strategies for nanoscale drug delivery systems, based on the unique molecular signatures of myeloid leukemia and EGFR/CD44-positive solid tumors, and the impact of novel discoveries in molecular tumor profiles on future chemotherapeutic protocols.

Molecular Monitoring in Acute Myeloid Leukemia Patients Undergoing Matched Unrelated Donor - Hematopoietic Stem Cell Transplantation: Single Center Experience.

INTRODUCTION: Minimal residual disease (MRD) assessment in acute myeloid leukemia (AML) cases is a complex, multi-modality process and, though much of its clinical implications at different points are extensively studied, it remains even now a challenging area. It is a disease the biology of which governs the modality of MRD assessment; in patients harboring specific molecular targets, high sensitivity techniques can be applied. On the other hand, relapse is considered as the leading cause of treatment failure in AML patients undergoing allogeneic hematopoietic stem cell transplantation (alloHSCT). MATERIALS AND METHODS: Since November 2018 until June 2020, 10 AML patients underwent matched unrelated donor (MUD) HSCT at the University Clinic of Hematology-Skopje, Republic of North Macedonia. Molecular markers were identified in a total of 4 patients; 3 patients expressed chimeric fusion transcripts; two RUNX-RUNX1T1 and one for CBFB-MYH11. One patient harbored mutation in the transcription factor CCAAT/enhancer binding protein α (CEBPA). Post-transplant MRD kinetics was evaluated by using quantitative polymerase chain reaction (RT-qPCR) or multiplex fluorescent-PCR every three months during the first two years after the transplantation. RESULTS: MRD negativity was achieved in three pre-transplant MRD positive patients by the sixth month of HSCT. They sustained hematological and molecular remission for 19, 9 and 7 months, respectively. The fourth patient died due to transplant-related complications. CONCLUSION: According to our experience, when molecularly-defined AML patients undergo HSCT, regular MRD monitoring helps predict impending relapse and direct future treatment strategies.

Influence of MSI and 18q LOH markers on capecitabine adjuvant monotherapy in colon cancer patients.

PURPOSE: The aim of this study was to evaluate whether pretreatment analysis of selected molecular markers can be used for the prediction of disease-free survival (DFS)/overall survival (OS) of capecitabine adjuvant monotherapy in colon cancer patients. PATIENTS AND METHODS: A total of 126 patients enrolled in a capecitabine Phase IV clinical trial were analyzed for microsatellite instability (MSI), 18q loss of heterozygosity (LOH), thymidylate synthase (TYMS) 5' variable number of tandem repeat (VNTR), and methylene tetrahydrofolate reductase (MTHFR) C677T variants. The significance in predicting 5-year DFS/OS was assessed by Kaplan-Meier and Cox regression analyses. RESULTS: The MSI-high (MSI-H) genotype was significantly associated with DFS (HR 0.205, 95% CI 0.05-0.88, P=0.033) and OS (HR 0.208, 95% CI 0.05-0.89, P=0.035) compared to the microsatellite stable genotype. In models stratified according to clinicopathologic characteristics, the MSI-H genotype remained a positive predictive factor for DFS/OS only in patients with stage III (P=0.023) and patients with tumors localized proximally to the splenic flexure (P=0.004). Distal colon cancers with 18q LOH have a greater survival rate when treated with capecitabine than patients with stable tumors (81.3% vs 50.0%, HR for relapse 0.348, 95% CI 0.13-0.97, P=0.043). TYMS 5'VNTR and MTHFR C677T variants were not associated with DFS or OS. CONCLUSION: MSI and 18q LOH markers have the potential to be utilized in the selection of colon cancer patients eligible for capecitabine adjuvant monotherapy.

Association of Single-Nucleotide Polymorhism C3435T in the ABCB1 Gene with Opioid Sensitivity in Treatment of Postoperative Pain.

BACKGROUND: The minimal effective analgesic concentration of opioids required for satisfactory analgesia may differ significantly among the patients. Genetic factors may contribute to the variable response to opioids by affecting their pharmacokinetics or pharmacodynamics. METHODS: Ninety nine patients undergoing abdominal surgery with colorectal anastomosis because of colorectal carcinoma were enrolled in the present study. C34535T was genotyped in all subjects and the patients were divided into three groups according to their genotype: CC-wild type homozygous, CT-mutant heterozygous and TT-mutant homozygous. Intravenous fentanyl, patient controlled analgesia was provided postoperatively for pain control in the first 24 hour after surgery. Opioid consumption, pain scores and the adverse side effects were evaluated. RESULTS: Our main result is that the patients in the CC genotype group consumed significantly more fentanyl (375.0 µg ± 43.1) than the patients in the TT group (295.0 µg ± 49.1) and the CT (356.4 µg ± 41.8) group in the treatment of postoperative pain. The patients in the TT group had lower VAS scores at 6h, 12h, 18 h and 24h postoperatively. There were no significant differences in the side effects among the three groups regarding the vomiting and the sedation score. The patients in the TT group had more frequently nausea score 1, than the patients in the other two groups. CONCLUSION: Our study indicates that the C3435T SNPs of the ABCB1 gene is associated with differences in the opioid sensitivity. The ABCB1 polymorphism may serve as an important genetic predictor to guide the acute pain therapy in postoperative patients.

Loss of Y Chromosome in Peripheral Blood of Colorectal and Prostate Cancer Patients.

BACKGROUND: Although age-related loss of chromosome Y (LOY) in normal hematopoietic cells is a well-known phenomenon, the phenotypic consequences of LOY have been elusive. However, LOY has been found in association with smoking, shorter survival and higher risk of cancer. It was suggested that LOY in blood cells could become a predictive biomarker of male carcinogenesis. AIMS, METHODS & FINDINGS: To investigate the association of LOY in blood cells with the risk for development of colorectal (CC) and prostate cancers (PC), we have analyzed DNA samples from peripheral blood of 101 CC male patients (mean age 60.5±11.9 yrs), 70 PC patients (mean age 68.8±8.0 yrs) and 93 healthy control males (mean age 65.8±16.6 yrs). The methodology included co-amplification of homologous sequences on chromosome Y and other chromosomes using multiplex quantitative fluorescent (QF) PCR followed by automatic detection and analysis on ABI 3500 Genetic Analyzer. The mean Y/X ratio was significantly lower in the whole group of cancer patients (0.907±0.12; p = 1.17x10-9) in comparison to the controls (1.015±0.15), as well as in CC (0.884±0.15; p = 3.76x10-9) and PC patients (0.941±0.06; p = 0.00012), when analyzed separately. Multivariate logistic regression analysis adjusting for LOY and age showed that LOY is a more significant predictor of cancer presence than age, and that age probably does not contribute to the increased number of subjects with detectable LOY in cancer patients cohort. CONCLUSION: In conclusion, our results support the recent findings of association of LOY in blood cells with carcinogenesis in males.

Search for the presence of occult hepatitis C in patients with treatment-induced viral clearance using an ultrasensitive assay.

Introduction: Occult hepatitis C is defined by the presence of virus in the peripheral blood mononuclear cells (PBMCs) and/or liver cells, in the absence of serum viremia. Objective: To detect the persistence of occult hepatitis C in hemodialysis (HD) patients and patients without renal disease (non-renal) with treatment-induced clearance of hepatitis C virus (HCV) infection, using assays with a very low detection limit of viremia. Methods: A group of 13 HD patients and a group of 43 non-renal patients, with treatment-induced HCV infection clearance were investigated in the study. The HD patients were treated with pegylated interferon alpha (PEG-IFN-α) only, while the non-renal patients were treated with a combination therapy of PEGIFN- α and ribavirin. Detection of a possible persistence of HCV RNA in the PBMCs and plasma samples was assessed by an ultrasensitive reverse transcription polymerase chain reaction (RT-PCR) assay (2 IU/ml). Results: HCV RNA was not detected in the PBMCs and plasma samples of HD patients and of non-renal patients, when assessed by the ultrasensitive RT-PCR assay. Conclusion: When a sensitive RT-PCR assay was applied, to determine if treatment induced clearance of HCV infection had been successful, occult hepatitis C could not be detected by an ultrasensitive assay, neither in HD nor in non-renal patients.

Genetic predictors of the response to the treatment of hepatitis C virus infection.

The genome-wide association studies have identified a strong association between interleukin 28B (IL28B) gene polymorphisms and the response to treatment in patients with hepatitis C virus (HCV) infection. The aim of the study was to evaluate the association between three most widely studied IL28B gene polymorphisms and the response to antiviral treatment of chronic hepatitis C. We performed the genotyping of the three IL28B gene polymorphisms: rs12979860, rs8099917, and rs12980275 in 72 Caucasian patients with chronic hepatitis C, previously treated with the combination therapy of pegylated interferon alpha (PEGIFN α) and ribavirin (RBV). The patients included in the study had finished the treatment regimen at least 6 months before enrolling in the study. We used the sustained viral response (SVR) for the evaluation of the effectiveness of the antiviral treatment, and it was tested with an assay with a sensitivity of 20 IU/mL. An SVR was achieved in 59.7% (43/72) of the treated patients. The three IL28B gene polymorphisms (CC genotype of rs12979860, TT genotype of rs8099917, and AA genotype of rs12980275) were associated with the SVR (p=0.029, p=0.016, and p=0.028, respectively) in the study patients with chronic hepatitis C treated with the combination therapy of PEGIFN α and RBV. The association of IL28B gene polymorphisms with the treatment response points to the possibility of personalized medicine for the treatment of HCV infection.

Single nucleotide polymorphisms near IL28B gene and response to treatment of chronic hepatitis C in hemodialysis patients.

BACKGROUND: It has been shown that single nucleotide polymorphisms (SNPs) near the interleukin 28B (IL28B) gene were associated with sustained virological response following standard antivirological treatment of chronic hepatitis C. OBJECTIVES: The aim of the study was to evaluate the association between SNPs near the IL28B gene and response to the treatment of chronic hepatitis C in hemodialysis patients. PATIENTS AND METHODS: The study group included 24 hemodialysis patients with chronic hepatitis C routinely treated with pegylated interferon α-2 a. HCV genotype 1 was the cause of chronic hepatitis C in all study participants. Sustained virological response was determined by an assay with a sensitivity of 20 IU/mL, 6 months after completion of the antivirological treatment. The genotyping of the three most widely studied IL28B gene polymorphisms (rs12979860, rs8099917, and rs12980275) was performed in all study participants. RESULTS: Sustained virological response was achieved in 50% of the treated patients. The treatment response was significantly associated with the CC genotype of rs12979860, TT genotype of rs8099917, and AA genotype of rs12980275 (p = 0.003, p = 0.009, and p = 0.012, respectively). CONCLUSIONS: The three most widely studied SNPs near the IL28B gene were associated with sustained virological response following antivirological treatment of chronic hepatitis C in hemodialysis patients.