Role of Biomarkers in the Integrated Management of Melanoma

Melanoma, which is an aggressive skin cancer, is currently the fifth and seventh most common cancer in men and women, respectively. The American Cancer Society reported that approximately 106,110 new cases of melanoma were diagnosed in the United States in 2021, with 7,180 people dying from the disease. This information could facilitate the early detection of possible metastatic lesions and the development of novel therapeutic techniques for melanoma. Additionally, early detection of malignant melanoma remains an objective of melanoma research. Recently, melanoma treatment has substantially improved, given the availability of targeted treatments and immunotherapy. These developments have highlighted the significance of identifying biomarkers for prognosis and predicting therapy response. Biomarkers included tissue protein expression, circulating DNA detection, and genetic alterations in cancer cells. Improved diagnostic and prognostic biomarkers are becoming increasingly relevant in melanoma treatment, with the development of newer and more targeted treatments. Here, the author discusses the aspects of biomarkers in the real-time management of patients with melanoma.

Discovery and directed evolution of nitroreductase enzymes for activation of prodrugs and PET imaging compounds

<p><b>Bacterial nitroreductase enzymes, which exhibit the capacity to reduce a wide range of nitroaromatic drugs, antibiotics and environmental pollutants, have shown promise in the activation of prodrugs such as CB1954 and PR-104A. Use of these prodrugs in gene-directed enzyme prodrug therapy (GDEPT) cancer treatment would allow for targeted chemotherapy in tumour cells following specific delivery of nitroreductases to these cancerous tissues, using specialised bacterial or viral vectors. However, one key limitation in nitroreductase-based GDEPT is the current inability to rapidly and non-invasively determine vector localisation and gene delivery prior to systemic administration of prodrug. Dual-purpose nitroreductases that exhibit the ability to activate both GDEPT prodrugs and radioisotope-labelled PET imaging probes, in a manner that renders them temporarily cell-entrapped for detection using a PET scanner, would facilitate clinical development of this treatment.</b></p> <p>Previous attempts to repurpose hypoxia-activated 2-nitroimidazole PET imaging probes for nitroreductase detection have suffered from relatively high background activation under hypoxia alone. The design of nextgeneration 5-nitroimidazole PET imaging probes, by our collaborators at the Auckland Cancer Society Research Centre (ACSRC), has resulted in much lower levels of hypoxia activation in vivo.</p> <p>This thesis describes attempts to generate improved nitroreductases that can activate a bespoke 5-nitroimidazole PET-capable imaging probe, S33. A 58-membered library of nitroreductase candidates, including enzymes from many different bacterial species and oxidoreductase families, was heterologously over-expressed in E. coli screening strains. Microplate-based screening strategies were then used to identify enzymes that exhibited the most activity with S33, based on the ability of high levels of activated S33 to induce DNA damage and (at very high levels) E. coli cell death. Following this, site-targeted libraries of two different promising nitroreductase NfsA homologues were screened for S33 activity, with selected variants from eachlibrary showing improvement in S33 activation over the parent nitroreductase. In parallel I performed error-prone PCR mutagenesis of a top NfsA variant and top NfsB variant, subjecting each to two rounds of random mutagenesis, and selecting improved variants using a specialised E. coli screening strain and fluorescence-activated cell sorting (FACS). Selected variants from the NfsB (but not NfsA) nitroreductase candidate library showed substantially improved capacity to activate S33 over the parent enzyme.</p> <p>As an alternative means for developing improved nitroreductase variants, two different nitroaromatic ‘anti-prodrugs’, the anthelmintic niclosamide and the antibiotic chloramphenicol, whose cytotoxic effects on E. coli can be mitigated by the presence of an over-expressed active nitroreductase, were used to select for improved S33-activating enzymes from a site-targeted NfsA library. Variants were discovered that exhibited improved ability to active S33 as well as other nitroaromatic substrates of interest. Finally, attempts to discover novel nitroreductases from nature through the screening of cloned soil metagenomic fragments, were made utilising a novel cloning strategy to improve expression of the cloned gene fragments in E. coli. Screening and selection of nitroreductase gene ragments was conducted using niclosamide as well as nitroaromatic compounds that change colour upon activation.</p>

Discovery and directed evolution of nitroreductase enzymes for activation of prodrugs and PET imaging compounds

<p><b>Bacterial nitroreductase enzymes, which exhibit the capacity to reduce a wide range of nitroaromatic drugs, antibiotics and environmental pollutants, have shown promise in the activation of prodrugs such as CB1954 and PR-104A. Use of these prodrugs in gene-directed enzyme prodrug therapy (GDEPT) cancer treatment would allow for targeted chemotherapy in tumour cells following specific delivery of nitroreductases to these cancerous tissues, using specialised bacterial or viral vectors. However, one key limitation in nitroreductase-based GDEPT is the current inability to rapidly and non-invasively determine vector localisation and gene delivery prior to systemic administration of prodrug. Dual-purpose nitroreductases that exhibit the ability to activate both GDEPT prodrugs and radioisotope-labelled PET imaging probes, in a manner that renders them temporarily cell-entrapped for detection using a PET scanner, would facilitate clinical development of this treatment.</b></p> <p>Previous attempts to repurpose hypoxia-activated 2-nitroimidazole PET imaging probes for nitroreductase detection have suffered from relatively high background activation under hypoxia alone. The design of nextgeneration 5-nitroimidazole PET imaging probes, by our collaborators at the Auckland Cancer Society Research Centre (ACSRC), has resulted in much lower levels of hypoxia activation in vivo.</p> <p>This thesis describes attempts to generate improved nitroreductases that can activate a bespoke 5-nitroimidazole PET-capable imaging probe, S33. A 58-membered library of nitroreductase candidates, including enzymes from many different bacterial species and oxidoreductase families, was heterologously over-expressed in E. coli screening strains. Microplate-based screening strategies were then used to identify enzymes that exhibited the most activity with S33, based on the ability of high levels of activated S33 to induce DNA damage and (at very high levels) E. coli cell death. Following this, site-targeted libraries of two different promising nitroreductase NfsA homologues were screened for S33 activity, with selected variants from eachlibrary showing improvement in S33 activation over the parent nitroreductase. In parallel I performed error-prone PCR mutagenesis of a top NfsA variant and top NfsB variant, subjecting each to two rounds of random mutagenesis, and selecting improved variants using a specialised E. coli screening strain and fluorescence-activated cell sorting (FACS). Selected variants from the NfsB (but not NfsA) nitroreductase candidate library showed substantially improved capacity to activate S33 over the parent enzyme.</p> <p>As an alternative means for developing improved nitroreductase variants, two different nitroaromatic ‘anti-prodrugs’, the anthelmintic niclosamide and the antibiotic chloramphenicol, whose cytotoxic effects on E. coli can be mitigated by the presence of an over-expressed active nitroreductase, were used to select for improved S33-activating enzymes from a site-targeted NfsA library. Variants were discovered that exhibited improved ability to active S33 as well as other nitroaromatic substrates of interest. Finally, attempts to discover novel nitroreductases from nature through the screening of cloned soil metagenomic fragments, were made utilising a novel cloning strategy to improve expression of the cloned gene fragments in E. coli. Screening and selection of nitroreductase gene ragments was conducted using niclosamide as well as nitroaromatic compounds that change colour upon activation.</p>

Cytology Reporting System for Lung Cancer from the Japan Lung Cancer Society and the Japanese Society of Clinical Cytology: An Extensive Study Containing More Benign Lesions

<b><i>Introduction:</i></b> The Japan Lung Cancer Society (JLCS) and the Japanese Society of Clinical Cytology (JSCC) have proposed a new four-tiered cytology reporting system for lung carcinoma (JLCS-JSCC system). Prior to the proposal, the Papanicolaou Society of Cytopathology (PSC) had proposed a revised reporting system (PSC system), which comprises the “neoplastic, benign neoplasm, and low-grade carcinoma” category (N-B-LG category), in addition to the 4 categories of the JLCS-JSCC system. This study aimed to evaluate the interobserver agreement of the JLCS-JSCC system with an additional dataset with more benign lesions in comparison with the PSC system. <b><i>Methods:</i></b> We analyzed 167 cytological samples, which included 17 benign lesions, obtained from the respiratory system. Seven observers classified these cases into each category by reviewing one Papanicolaou-stained slide per case according to the JLCS-JSCC system and PSC system. <b><i>Results:</i></b> The interobserver agreement was moderate in the JLCS-JSCC (<i>k</i> = 0.499) and PSC (<i>k</i> = 0.485) systems. Of the 167 samples, 17 samples were benign lesions: 7 pulmonary hamartomas, 5 sclerosing pneumocytomas, 2 squamous papillomas, one solitary fibrous tumor, one meningioma, and one lymphocytic proliferation. There were diverse sample types as follows: 11 touch smears, 3 brushing smears, 2 aspirations, and one sputum sample. Fourteen samples (82.3%) were categorized into “negative” or “atypical” by more than half of the observers in the JLCS-JSCC system. Conversely, 3 samples were categorized as “suspicious” or “malignant” by more than half of the observers in the JLCS-JSCC system. On the other hand, 11 samples (64.7%) were categorized into the N-B-LG category by more than half of the observers in the PSC system. <b><i>Conclusions:</i></b> The concordance rate in the JLCS-JSCC system was slightly higher than that in the PSC system; however, the interobserver agreement was moderate in both the JLCS-JSCC and PSC systems. These results indicate that both the JLCS-JSCC and PSC systems are clinically useful. Therefore, both systems are expected to have clinical applications. It may be important to integrate the 2 systems and construct a universal system that can be used more widely in clinical practice.

Qualities of Culturally and Religiously Sensitive Practice: A Cross-Sectional Study

Background: Culture and religion influence lived experience and particularly dying and grieving. Research has largely focused on exploring culturally and religiously sensitive practices, but not necessarily in palliative and hospice care or across nations. Acquired knowledge from the more advanced end-of-life care systems (eg the UK) tends to be generalized to other contexts where its cultural appropriation is not tested. Aim: This study explored the different qualities, among hospice and palliative professionals in Cyprus, describing cultural competence, cultural humility, and religious literacy. Design: A cross-sectional study of 41 palliative and hospice professionals in Cyprus, with the use of a 5-point Likert style questionnaire ( a = 0.898). Setting: The study took place in Cyprus and participants were recruited from across palliative and hospice care organizations, including the only hospice in Cyprus, Cyprus Association of Cancer Patients and Friends (PASYKAF), and the Cyprus Anti-Cancer Society (CACS). Results: This study found that there are four main qualities that lead to effective culturally and religiously sensitive practice—informed decision-making, respect, adaptability, and nonjudgmental practice. Conclusions: Future education and training of professionals can consider these findings to appropriate approaches in practice that fit the Cypriot end-of-life care context more effectively.

Cohort Profile: The Socioeconomic Consequences in Adult Life After Childhood Cancer in Scandinavia (SALiCCS) Research Programme

IntroductionThe growing number of survivors of childhood cancer, with many years of life ahead, demonstrates the increasing clinical and public health relevance of investigating the risks of social and socioeconomic impairment after a childhood cancer diagnosis and the life-saving treatment. To enrich understanding of the mental, social and socioeconomic difficulties that childhood cancer survivors may face during their life-course, identify particularly vulnerable survivors and overcome the limitations of previous research, we initiated the Socioeconomic Consequences in Adult Life after Childhood Cancer in Scandinavia (SALiCCS) research programme.MethodsThis Nordic cross-border research programme is a collaboration between the Danish Cancer Society, the Finnish Cancer Registry and Karolinska Institutet to investigate a broad range of mental, social and socioeconomic conditions in long-term childhood cancer survivors in Denmark, Finland and Sweden. SALiCCS is based on a registry-based matched cohort design, comprising five-year survivors of cancer diagnosed at ages 0–19 years (1971–2008 in Denmark, 1971–2009 in Finland, 1971–2011 in Sweden), age-, sex- and country-matched population comparisons and sibling comparisons who were followed over time. Outcomes of interest included mental disorders, educational achievements, employment and profession, family life and the need of social security benefits. Individual-level data linkage among various national registries provided the data for the research programme.ResultsThe SALiCCS core population comprises 21,292 five-year survivors, 103,303 population comparisons and 29,644 siblings as a second comparison group. The most common diagnoses in survivors were central nervous system tumours, leukaemias and lymphomas.DiscussionSALiCCS is the largest, most comprehensive population-based research initiative in this field, based on high-quality registry data with minimal risk of bias. The findings will be informative for evidence-based survivorship care targeting not only somatic late effects but also psychosocial impairments.

British Gynaecological Cancer Society recommendations for women with gynecological cancer who received non-standard care during the COVID-19 pandemic

During the COVID-19 pandemic, pressures on clinical services required adaptation to how care was prioritised and delivered for women with gynecological cancer. This document discusses potential ‘salvage’ measures when treatment has deviated from the usual standard of care. The British Gynaecological Cancer Society convened a multidisciplinary working group to develop recommendations for the onward management and follow-up of women with gynecological cancer who have been impacted by a change in treatment during the pandemic. These recommendations are presented for each tumor type and for healthcare systems, and the impact on gynecological services are discussed. It will be important that patient concerns about the impact of COVID-19 on their cancer pathway are acknowledged and addressed for their ongoing care.