Reactive oxygen species-mediated mechanisms of action of targeted cancer therapy

Abstract Targeted cancer therapies, involving tyrosine kinase inhibitors and monoclonal antibodies, for example, have recently led to substantial prolongation of survival in many metastatic cancers. Compared with traditional chemotherapy and radiotherapy, where reactive oxygen species (ROS) have been directly linked to the mediation of cytotoxic effects and adverse events, the field of oxidative stress regulation is still emerging in targeted cancer therapies. Here, we provide a comprehensive review regarding the current evidence of ROS-mediated effects of antibodies and tyrosine kinase inhibitors, use of which has been indicated in the treatment of solid malignancies and lymphomas. It can be concluded that there is rapidly emerging evidence of ROS-mediated effects of some of these compounds, which is also relevant in the context of drug resistance and how to overcome it

Optimization of measurement mode and sample processing for FTIR microspectroscopy in skin cancer research

Abstract The use of Fourier Transform Infrared (FTIR) microspectroscopy to study cancerous cells and tissues has gained popularity due to its ability to provide spatially resolved information at the molecular level. Transmission and transflection are the commonly used measurement modes for FTIR microspectroscopy, and the tissue samples measured in these modes are often paraffinized or deparaffinized. Previous studies have shown that variability in the spectra acquired using different measurement modes and sample processing methods affect the result of the analysis. However, there is no protocol that standardizes the mode of measurement and sample processing method to achieve the best classification result. This study compares the spectra of primary (IPC-298) and metastatic (SK-MEL-30) melanoma cell lines acquired in both transmission and transflection modes using paraffinized and deparaffinized samples to determine the optimal combination for accurate classification. Significant differences were observed in the spectra of the same cell line measured in different modes and with or without deparaffinization. The PLS-DA model built for the classification of two cell lines showed high accuracy in each case, suggesting that both modes and sample processing alternatives are suitable for differentiating cultured cell samples using supervised multivariate analysis. The biochemical information contained in the cells capable of discriminating two melanoma cell lines is present regardless of mode or sample type used. However, the paraffinized samples measured in transflection mode provided the best classification

Discrimination of melanoma cell lines with Fourier Transform Infrared (FTIR) spectroscopy

Abstract Among skin cancers, melanoma is the lethal form and the leading cause of death in humans. Melanoma begins in melanocytes and is curable at early stages. Thus, early detection and evaluation of its metastatic potential are crucial for effective clinical intervention. Fourier transform infrared (FTIR) spectroscopy has gained considerable attention due to its versatility in detecting biochemical and biological features present in the samples. Changes in these features are used to differentiate between samples at different stages of the disease. Previously, FTIR spectroscopy has been mostly used to distinguish between healthy and diseased conditions. With this study, we aim to discriminate between different melanoma cell lines based on their FTIR spectra. Formalin-fixed paraffin embedded samples from three melanoma cell lines (IPC-298, SK-MEL-30 and COLO-800) were used. Statistically significant differences were observed in the prominent spectral bands of three cell lines along with shifts in peak positions. A partial least square discriminant analysis (PLS-DA) model built for the classification of three cell lines showed an overall accuracy of 92.6% with a sensitivity of 85%, 95.75%, 96.54%, and specificity of 97.80%, 92.14%, 98.64% for the differentiation of IPC-298, SK-MEL-30, and COLO-800, respectively. The results suggest that FTIR spectroscopy can differentiate between different melanoma cell lines and thus potentially characterize the metastatic potential of melanoma

The use of Fourier Transform Infrared (FTIR) spectroscopy in skin cancer research:a systematic review

Abstract Skin cancers are one of the most frequently occurring diseases in humans that pose severe health issues. Fourier Transform Infrared (FTIR) spectroscopy in cancer research has gained considerable attention because of its ability to provide biochemical information in addition to being compatible with traditional histopathology. With this review, we aim to identify all skin cancer studies which have been conducted using FTIR spectroscopy and depict different methodologies that have been used to analyze FTIR spectroscopic data of skin cancers. We conducted the systematic review following PRISMA guidelines for which three databases, Scopus, PubMed and Web of Science, were searched from commencement to 16 January 2019. All the studies which used FTIR spectroscopy for skin cancer research were included in the review. A total of 35 studies were found eligible to be included in the review. Of these, 21 studies were based on melanoma, 6 studies on BCC, 2 studies on SCC, and 2 on lymphocytes. The remaining 4 studies aimed to differentiate between various skin cancer types. The potential of FTIR spectroscopy for many relevant aspects of skin cancer research has already been demonstrated, but more work is needed to establish FTIR spectroscopy as a routine method in the field

NRF3 decreases during melanoma carcinogenesis and Is an independent prognostic marker in melanoma

Abstract The prognostic significance of the major redox regulator, nuclear factor erythroid-2-related factor 2 (NRF2), is recognized in many cancers, but the role of NRF3 is not studied. Analysis from the Gene Expression Omnibus datasets showed that NRF3 mRNA levels increased from benign to dysplastic naevi (p = 0.04). We characterized the immunohistochemical expression of NRF3 in 81 naevi, 67 primary skin melanomas, and 51 lymph node metastases. The immunohistochemical expression of cytoplasmic NRF3 decreased from benign to dysplastic naevi (p < 0.001) and further to primary melanomas (p < 0.001). High cytoplasmic NRF3 protein expression in pigment cells of the primary melanomas associated with worse melanoma-specific survival in multivariate analysis, specifically in the subgroup of patients with the lymph node metastases at the time of diagnosis (hazard ratio 3.179; 95% confidence interval 1.065-9.493; p = 0.038). Intriguingly, we did not observe associations between NRF3 and the traditional prognostic factors such as Breslow thickness, ulceration, or stage. Together, this data represents the primary description about the role of NRF3 in pigment tumours that is worthy of further explorations

Different chemokine profile between systemic and testicular diffuse large B-cell lymphoma

Abstract Although treatment for diffuse large B-cell lymphoma (DLBCL) has taken some notable steps in the 2000s, there are still subgroups of patients suffering from high mortality and relapse rates. To further improve treatment outcomes, it is essential to discover new mechanisms of chemotherapy resistance and create new treatment approaches to overcome them. In the present study, we analyzed the expression of chemokines and their ligands in systemic and testicular DLBCL. From our biopsy sample set of 21 testicular and 28 systemic lymphomas, we were able to demonstrate chemokine profile differences and identify associations with clinical risk factors. High cytoplasmic CXCL13 expression had correlations with better treatment response, lower disease-related mortality, and limited stage. This study suggests that active CXCR5/CXCL13 signaling could overtake the CXCR4/CXCL12 axis, resulting in a better prognosis

NRF1 and NRF2 mRNA and protein expression decrease early during melanoma carcinogenesis:an insight into survival and microRNAs

Abstract The prognostic significance of the major redox regulator nuclear factor erythroid-2-related factor (NRF2) is recognized in many cancers, but the role of NRF1 is not generally well understood in cancer. Our aim was to investigate these redox transcription factors in conjunction with redox-related microRNAs in naevi and melanoma. We characterized the immunohistochemical expression of NRF1 and NRF2 in 99 naevi, 88 primary skin melanomas, and 67 lymph node metastases. In addition, NRF1 andNRF2 mRNA and miR-23B, miR-93, miR-144, miR-212, miR-340, miR-383, and miR-510 levels were analysed with real-time qPCR from 54 paraffin-embedded naevi and melanoma samples. The immunohistochemical expression of nuclear NRF1decreased from benign to dysplastic naevi (p < 0:001) and to primary melanoma (p<0:001) and from primary melanoma to metastatic lesions (p=0:012). Also, NRF1 mRNA levels decreased from benign naevi to dysplastic naevi (p=0:034). Similarly, immunopositivity of NRF2 decreased from benign to dysplastic naevi (p=0:02) and to primary lesions (p=0:018). NRF2mRNA decreased from benign to dysplastic naevi and primary melanomas (p=0:012). Analysis from the Gene Expression Omnibus datasets supported the mRNA findings. High nuclear immunohistochemical NRF1 expression in pigment cells associated with a worse survival (p=0:048) in patients with N0 disease at the time of diagnosis, and high nuclear NRF2 expression in pigment cells associated with a worse survival (p=0:033) in patients with M0 disease at the time of diagnosis. In multivariate analysis, neither of these variables exceeded the prognostic power of Breslow. The levels of miR-144 and miR-212 associated positively with ulceration (p=0:012 and p=0:027, respectively) while miR-510 levels associated positively with lymph node metastases at the time of diagnosis (p=0:004). Furthermore, the miRNAs correlated negatively with the immunohistochemical expression of NRF1 and NRF2 but positively with their respective mRNA. Together, this data sheds new light about NFE2L family factors in pigment tumors and suggests that these factors are worth for further explorations

Thioredoxin‐1 as a biological predictive marker for selecting diffuse large B‐cell lymphoma patients for etoposide‐containing treatment

Abstract Objective: In diffuse large B‐cell lymphoma (DLBCL), there is an unmet medical need to select patients who would benefit from intensified frontline treatments such as adding etoposide to an R‐CHOP regimen. Methods: The present work included a retrospective clinical analysis of two patient cohorts and an in vitro study. Primary biopsy samples from DLBCL patients treated with an etoposide‐containing high‐dose regimen (n = 37) and etoposide‐containing frontline treatment (n = 69, R‐CHOEP) were studied using immunohistochemical thioredoxin‐1 (Trx1) staining. Two DLBCL cell lines expressing Trx1 were cultured, and their expression was silenced using the small interfering RNA knockdown technique. Chemoresistance was tested with doxorubicin, etoposide, vincristine, prednisolone and carboplatin. Results: Thioredoxin‐1 knockdown sensitised DLBCL cells to doxorubicin (P < 0.0001) but decreased etoposide‐induced cell death (P < 0.00001). In DLBCL patients who received etoposide‐containing frontline treatment, low cytoplasmic Trx1 expression was associated with inferior 5‐year overall survival (46% vs 76%, P = 0.026) and disease‐specific survival (68% vs 90%, P = 0.026). Conclusions: Strong Trx1 expression appears to increase drug resistance to doxorubicin but sensitises cells to etoposide. This implies that Trx1 expression might be the first predictive biological marker to select the patients who might benefit from adding etoposide to R‐CHOP immunochemotherapy

Peroxiredoxin 6 serum levels and risk of neutropenic infections in diffuse large B-cell lymphoma

Abstract Background/Aim: Diffuse large B‐cell lymphoma (DLBCL) is an aggressive malignancy where antioxidant enzyme peroxiredoxin 6 (Prx6) has previously been associated with adverse outcomes. Its systemic effects in DLBCL are unknown. Materials and methods: This study included 53 patients with DLBCL, five patients with primary central nervous system lymphoma (PCNSL) and 20 healthy controls. The expression of Prx6 was evaluated immunohistochemically in DLBCL tissue samples and compared to its expression in blood serum. Results: Prx6 expression was the highest in healthy controls, followed by DLBCL patients and PCNSL patients. Febrile neutropenic infection after the first treatment course was associated with low pre-treatment Prx6 serum levels (<14 ng/ml) (p=0.025, OR=8.615, 95% confidence interval=1.032‐71.933). Serum levels of Prx6 recovered after treatment (p=0.006). Conclusion: Patients with low Prx6 levels might be more prone to treatment‐related adverse effects through elevated levels of oxidative stress

Nuclear factor erythroid 2-related factors 1 and 2 are able to define the worst prognosis group among high-risk diffuse large B cell lymphomas treated with R-CHOEP

Abstract Aims: Oxidative stress markers and antioxidant enzymes have previously been shown to have prognostic value and associate with adverse outcome in patients with diffuse large B cell lymphoma (DLBCL). Nuclear factor erythroid 2-related factor 1 (Nrf1) and factor 2 (Nrf2) are among the principal inducers of antioxidant enzyme production. Kelch ECH associating protein 1 (Keap1) is a negative regulator of Nrf2, and BTB (BR-C, ttk and bab) domain and CNC homolog 1 (Bach1) represses the function of both factors. Their significance in DLBCL prognosis is unknown. Methods: Diagnostic biopsy samples of 76 patients with high-risk DLBCL were retrospectively stained with immunohistochemistry for Nrf1, Nrf2, Keap1 and Bach1, and correlated with clinical data and outcome. Results: Nuclear Nrf2 and nuclear Bach1 expression were associated with adverse clinical features (anaemia, advanced stage, high IPI, high risk of neutropaenic infections), whereas cytoplasmic Nrf1 and Nrf2 were associated with favourable clinical presentation (normal haemoglobin level, no B symptoms, limited stage). None of the evaluated factors could predict survival alone. However, when two of the following parameters were combined: high nuclear score of Nrf2, low nuclear score of Nrf1, high cytoplasmic score of Nrf1 and low cytoplasmic score of Keap1 were associated with significantly worse overall survival. Conclusions: Nrf1 and Nrf2 are relevant in disease presentation and overall survival in high-risk DLBCL. Low nuclear expression of Nrf1, high cytoplasmic expression of Nrf1, high nuclear expression of Nrf2 and low cytoplasmic expression of Keap1 are associated with adverse outcome in this patient group